WorldWideScience

Sample records for river transposition region

  1. Didactic Transposition

    DEFF Research Database (Denmark)

    Achiam, Marianne

    The term didactic transposition refers to the deconstruction and reconstruction of science knowledge, values or practices in order to make them teachable. In this paper, I present the theoretical framework that has grown around this notion. I use examples from different levels of science education...... and different subjects to illustrate how science is transformed in any teaching undertaking, and how that transformation influences the way science is experienced and appropriated by learners. The chosen examples also illustrate the development of the notion of didactic transposition from a descriptive...... framework to the more normative construct of today (the Anthropological Theory of Didactics or ATD), where it converges with other comparable frameworks, e.g. the Model of Educational Reconstruction....

  2. Museographic transposition

    DEFF Research Database (Denmark)

    Mortensen, Marianne Foss

    2010-01-01

    is reported. Museographic transposition was used as an analytical framework to investigate the development of an existing museum exhibit on animal adaptations to darkness. The analysis yielded a descriptive model of exhibition engineering as a three-stage process in which simultaneous processes......Science museums define the objectives of their exhibitions in terms of visitor learning outcomes, yet exhibition engineering staff lack theoretical and empirical research findings on which to base the creation of these educational environments. Here, a first step towards providing such research...... of epistemological development and museum-pedagogical development result in the curatorial brief which forms the basis of the subsequent museographic development of the physical exhibit. Examples are discussed which illustrate the use of the model in identifying exhibition inconsistencies, but also in generating new...

  3. Sand fly (Diptera, Psychodidae, Phlebotominae) abundance and diversity in areas affected by the São Francisco River transposition project in Ceará State, Brazil.

    Science.gov (United States)

    Dos Santos Silva, Júlia; Caranha, Lindemberg; Moura Santos, Fabrício Kássio; Dos Santos, Antonio Pereira; Rodrigues da Silva, Luiz Osvaldo; Ferreira Rangel, Elizabeth

    2017-08-29

    Entomological surveillance of sand fly vectors was carried out to support leishmaniasis prevention and control measures in areas affected by the São Francisco River Transposition Project. Sand flies were collected monthly between May 2011 and December 2014 in seven municipalities: Missão Velha, Brejo Santo, Lavras da Mangabeira, Iguatu, Mauriti, Jaguaribe and Jaguaretama, in dwellings, peridomicile and forest areas for three consecutive days, for a period of 12 h each day (18:00 to 06:00 h). Differences in species composition between sites were tested with Shannon's diversity index, the similarity between habitats was estimated by the Sørensen's qualitative similarity index and, for the most abundant species in each municipality, a standardized index of species abundance was applied. The influence of climatic factors on sand fly population densities was analyzed using Spearman's correlation coefficients. A total of 214,213 sand fly specimens belonging to 18 species were captured. The most abundant species in all municipalities was Lutzomyia longipalpis (Lutz & Neiva, 1912). The municipalities of Mauriti and Missão Velha stand out in terms of high species richness, with the latter exhibiting the greatest diversity. The number of sand flies in the Iguatu, Jaguaribe and Jaguaretama municipality was higher during the rainy months, whereas the populations declined in the drier months; the sand fly population density in other municipalities (Missão Velha, Brejo Santo, Lavras de Mangabeira and Mauriti) showed negative correlation with rainfall. This study confirms the presence of several Leishmania spp. vectors in the seven municipalities affected by the São Francisco River Transposition Project, with Lu. longipalpis being the most abundant species at all study sites. Vector populations in these municipalities should be monitored, ultimately to assess the associations between environmental changes and sand fly population dynamics and leishmaniasis transmission

  4. Research on the river function regionalization

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objectives, principles, classification system, zoning method and procedure of river function region-alization were investigated systematically based on the present status of modern river regulation and function requirement. Considering the ecosystem continuity and river function integrality, a river is suggested to be divided into five function zones: ecological protection zone, habitat restoration zone, exploitation and utilization zone, buffer zone,and transition zone, based on the developed intensity and the function characteristics of the river. In this paper, not only the five function zones were described qualitatively, but also the quantitative examination method on how to identify their function zone types was given. A double-criterion partitioning scheme was proposed according to the functional zoning diagram constructed by the evaluation of the social and ecological function of rivers. Finally, the procedures of river function regionalization were shown.

  5. Mutational analysis of the PITX2 coding region revealed no common cause for transposition of the great arteries (dTGA

    Directory of Open Access Journals (Sweden)

    Goldmuntz Elizabeth

    2005-05-01

    Full Text Available Abstract Background PITX2 is a bicoid-related homeodomain transcription factor that plays an important role in asymmetric cardiogenesis. Loss of function experiments in mice cause severe heart malformations, including transposition of the great arteries (TGA. TGA accounts for 5–7% of all congenital heart diseases affecting 0.2 per 1000 live births, thereby representing the most frequent cyanotic heart defect diagnosed in the neonatal period. Methods To address whether altered PITX2 function could also contribute to the formation of dTGA in humans, we screened 96 patients with dTGA by means of dHPLC and direct sequencing for mutations within the PITX2 gene. Results Several SNPs could be detected, but no stop or frame shift mutation. In particular, we found seven intronic and UTR variants, two silent mutations and two polymorphisms within the coding region. Conclusion As most sequence variants were also found in controls we conclude that mutations in PITX2 are not a common cause of dTGA.

  6. Heuristics for the transposition distance problem.

    Science.gov (United States)

    Dias, Ulisses; Dias, Zanoni

    2013-10-01

    Transpositions are large-scale mutational events that occur when a block of genes moves from a region of a chromosome to another region within the same chromosome. The transposition distance problem is the minimum number of transpositions required to transform one genome into another. Recently, Bulteau et al. [Bulteau L, Fertin G, Rusu U, Automata, Languages and Programming, Vol. 6755 of Lecture Notes in Computer Science, pp. 654-665, Springer Berlin, Heidelberg, 2011] proved that finding the transposition distance is a NP-Hard problem. Some approximation algorithm for this problem have been presented to date [Bafna V, Pevzner PA, SIAM J Discr Math11(2):224-240, 1998; Elias I, Hartman T, IEEE/ACM Trans Comput Biol Bioinform3(4):369-379, 2006; Mira CVG, Dias Z, Santos HP, Pinto GA, Walter ME, Proc 3rd Brazilian Symp Bioinformatics (BSB'2008), pp. 115-126, Santo André, Brazil, 2008; Walter MEMT, Dias Z, Meidanis J, Proc String Processing and Information Retrieval (SPIRE'2000), pp. 199-208, Coruña, Spain, 2000]. Here we focus on developing heuristics to provide an improved approximated solution. Our approach outperforms other algorithms on small sized permutations. We also show that our algorithm keeps the good performance on longer permutations.

  7. Congenitally corrected transposition

    Directory of Open Access Journals (Sweden)

    Debich-Spicer Diane

    2011-05-01

    Full Text Available Abstract Congenitally corrected transposition is a rare cardiac malformation characterized by the combination of discordant atrioventricular and ventriculo-arterial connections, usually accompanied by other cardiovascular malformations. Incidence has been reported to be around 1/33,000 live births, accounting for approximately 0.05% of congenital heart malformations. Associated malformations may include interventricular communications, obstructions of the outlet from the morphologically left ventricle, and anomalies of the tricuspid valve. The clinical picture and age of onset depend on the associated malformations, with bradycardia, a single loud second heart sound and a heart murmur being the most common manifestations. In the rare cases where there are no associated malformations, congenitally corrected transposition can lead to progressive atrioventricular valvar regurgitation and failure of the systemic ventricle. The diagnosis can also be made late in life when the patient presents with complete heart block or cardiac failure. The etiology of congenitally corrected transposition is currently unknown, and with an increase in incidence among families with previous cases of congenitally corrected transposition reported. Diagnosis can be made by fetal echocardiography, but is more commonly made postnatally with a combination of clinical signs and echocardiography. The anatomical delineation can be further assessed by magnetic resonance imaging and catheterization. The differential diagnosis is centred on the assessing if the patient is presenting with isolated malformations, or as part of a spectrum. Surgical management consists of repair of the associated malformations, or redirection of the systemic and pulmonary venous return associated with an arterial switch procedure, the so-called double switch approach. Prognosis is defined by the associated malformations, and on the timing and approach to palliative surgical care.

  8. O Comitê da Bacia Hidrográfica do Rio São Francisco e a Gestão das Águas: O Conflito Exposto a Partir da Transposição do Rio São Francisco | The São Francisco River Basin Committee and Water Management Conflict Arising from the Transposition of The River

    Directory of Open Access Journals (Sweden)

    Ana Paula Novais Pires

    2014-05-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE Introduction: The São Francisco River Basin Committee (CBHSF was set up by presidential decree in 2001 with the aim of achieving decentralized and participatory management of its water. The São Francisco River flows overland for 2700 km from its source in the Serra da Canastra (MG to its mouth between Sergipe (SE and Alagoas (AL. The river passes through the states of Bahia (BA, Pernambuco (PE, Goiás (GO and the Federal District (DF. Central to the discussion in this research on the transposition of the São Francisco River is question of conflict concerning water management in the São Francisco River Basin Committee, making a nonsense of its power to function, contrary to the project, and the Federal Government which initiated the work and approved the budget. Hence, this study aims to analyze water management in the São Francisco river basin from the initiation of the CBHSF in order to understand how approval of the project and implementation of the work ran against the statutory representation of the committee. Methodology and Development: Having a qualitative approach, the study will be divided between theoretical research based on authors who study the topic of water and its transformation into a water resource and the major landowners of the north-east semi-arid zone in the context of transposition; the dynamics and politics of the river basin; as well as the role of the river basin committees in the process of decentralizing Brazilian water management, specifically concerning the São Francisco River and its state and interstate committees. Documentary research will take into account National Water Resources Law 9.433/1997; state water policies; documentary archives of the river basin committees (state and interstate, as well as the agencies participating in the integration project, such as the National Water Agency (ANA, the Integration Ministry (MI, and the Environment Ministry (MMA

  9. Urban rivers as hotspots of regional nitrogen pollution.

    Science.gov (United States)

    Zhang, Xiaohong; Wu, Yiyun; Gu, Baojing

    2015-10-01

    Excess nitrogen inputs to terrestrial ecosystems via human activities have deteriorated water qualities on regional scales. Urban areas as settlements of over half global population, however, were usually not considered in the analysis of regional water pollution. Here, we used a 72-month monitoring data of water qualities in Hangzhou, China to test the role of urban rives in regional nitrogen pollution and how they response to the changes of human activities. Concentrations of ammonium nitrogen in urban rivers were 3-5 times higher than that in regional rivers. Urban rivers have become pools of reactive nitrogen and hotspots of regional pollution. Moreover, this river pollution is not being measured by current surface water monitoring networks that are designed to measure broader regional patterns, resulting in an underestimation of regional pollution. This is crucial to urban environment not only in China, but also in other countries, where urban rivers are seriously polluted.

  10. Mutational analysis of the PITX2 coding region revealed no common cause for transposition of the great arteries (dTGA)

    OpenAIRE

    Goldmuntz Elizabeth; Rüdiger Heinz-Juergen; Schön Karin; Roeth Ralph; Niesler Beate; Muncke Nadja; Goodship Judith; Rappold Gudrun

    2005-01-01

    Abstract Background PITX2 is a bicoid-related homeodomain transcription factor that plays an important role in asymmetric cardiogenesis. Loss of function experiments in mice cause severe heart malformations, including transposition of the great arteries (TGA). TGA accounts for 5–7% of all congenital heart diseases affecting 0.2 per 1000 live births, thereby representing the most frequent cyanotic heart defect diagnosed in the neonatal period. Methods To address whether altered PITX2 function ...

  11. Bounded Rationality in Transposition Processes

    DEFF Research Database (Denmark)

    Vollaard, Hans; Martinsen, Dorte Sindbjerg

    2014-01-01

    Studies explaining the timeliness and correctness of the transposition of EU directives into national legislation have provided rather inconclusive findings. They do not offer a clear-cut prediction concerning the transposition of the patients’ rights directive, which is one of the first that con......Studies explaining the timeliness and correctness of the transposition of EU directives into national legislation have provided rather inconclusive findings. They do not offer a clear-cut prediction concerning the transposition of the patients’ rights directive, which is one of the first...... perspective may affect the commonly employed explanatory factors of administrative capacities, misfit and the heterogeneity of preferences among veto players. To prevent retrospective rationalisation of the transposition process, this paper traces this process as it unfolded in Denmark and the Netherlands...

  12. Fostering a regional vision on river systems by remote sensing

    Science.gov (United States)

    Bizzi, S.; Piegay, H.; Demarchi, L.

    2015-12-01

    River classification and the derived knowledge about river systems have been relying until recently on discontinuous field campaigns and visual interpretation of aerial images. For this reason, building a regional vision on river systems based on a systematic and coherent set of hydromorphological indicators was, and still is, a research challenge. Remote sensing data, since some years, offer notable opportunities to shift this paradigm offering an unprecedented amount of spatially distributed data over large scales, such as regional. Here, we have implemented a river characterization framework based on color infrared orthophotos at 40 cm and a LIDAR derived DTM at 5 m acquired simultaneously in 2009-2010 for all Piedmont Region Italy (25400 kmq). 1500 km of river systems have been characterized in terms typology, geometry and topography of hydromorphological features. The framework delineates the valley bottom of each river course, and maps by a semi-automated procedure water channels, unvegetated and vegetated sediment bars, islands, and riparian corridors. Using a range of statistical techniques the river systems have been segmented and classified with an objective, quantitative, and then repeatable approach. Such regional database enhances our ability to address a number of research and management challenges, such as: i) quantify shape and topography of channel forms for different river functional types, and investigate their relationships with potential drivers like hydrology, geology, land use and historical contingency; ii) localize most degraded and better functioning river stretches so to prioritize finer scale monitoring and set quantifiable restoration targets; iii) provide indication for future RS acquisition campaigns so to start monitoring river processes at the regional scale. The Piedmont Region in Italy is here used as a laboratory of concrete examples and analyses to discuss our current ability to answer to these challenges in river science.

  13. Regional Cooperation Efforts in the Mekong River Basin: Mitigating river-related security threats and promoting regional development

    Directory of Open Access Journals (Sweden)

    Susanne Schmeier

    2009-01-01

    Full Text Available The development of international rivers is often perceived as leading to conflicts or even water wars. However, as the development of the Mekong River shows, cooperation has not only prevailed in the last decades, but River Basin Organizations (RBOs, established to mitigate river-related conflicts and/or develop the river basin, have also contributed to the emergence of more general cooperation structures, mainly by creating spill-over effects in other issue-areas, bringing cooperation to policy fields beyond the river itself. This article assesses the contribution of the Mekong River Commission (MRC and the Greater Mekong Sub-Region (GMS to the sustainable development of the Mekong Region as well as to the promotion of regional cooperation in mainland South-East Asia in general. --- Die Entwicklung grenzüberschreitender Flüsse wird oft mit Konflikten oder gar Kriegen um Wasser assoziiert. Wie jedoch die Entwicklung im Mekong-Becken zeigt, waren die vergangenen Jahrzehnte nicht nur von Kooperation gezeichnet, sondern Flussbeckenorganisationen konnten außerdem dazu beitragen, weitreichendere Kooperationsstrukturen zu entwickeln, die sich auf andere Politikfelder ausdehnen. Dieser Artikel beschäftigt sich mit dem Beitrag der Mekong River Commission (MRC und der Greater Mekong Sub-Region (GMS zur nachhaltigen Entwicklung in der Mekong Region sowie zur Förderung allgemeiner regionaler Kooperation im Festländischen Südostasien.

  14. Colonial Education and Women of the Cross River Region of ...

    African Journals Online (AJOL)

    Colonial Education and Women of the Cross River Region of Nigeria, 1900 – 1960: An Appraisal. ... foundation on which subsequent generations of educated women such as medical doctors, ... The paper concludes that more attention should

  15. The coordination of regional interest in developing river basin

    Institute of Scientific and Technical Information of China (English)

    Chen Xiangman

    2006-01-01

    River basin is a special region with the characteristics of entirety and relation, regionality and diversity,gradation and network, openness and dissipation etc. It is an important unit that organizes and governs national economy as well as a natural region. In river basin, all natural essential factors relate closely each other, and there is remarkable influence between inter-regions. In the process of developing river basin, the multiplex main interest body,the diverse interest demand and the multi-ways of interest realization constitute a complicated interest network, and result in various contradictions and conflicts. Therefore, effective regional interest coordination mechanism should be established to coordinate various regional interest relations. They are the public interest realization mechanism, the fair interest assignment mechanism, the effective interest integration mechanism, the expedited interest expression mechanism and the reasonable interest compensative mechanism.

  16. Transposition of the Greater Arteries (TGA)

    Science.gov (United States)

    ... Atrioventricular Canal Defect Transposition of the Great Arteries Coarctation of the Aorta Truncus Arteriosus Single Ventricle Defects ... Atrioventricular Canal Defect Transposition of the Great Arteries Coarctation of the Aorta Truncus Arteriosus Single Ventricle Defects ...

  17. Non-conformable, partial and conformable transposition

    DEFF Research Database (Denmark)

    König, Thomas; Mäder, Lars Kai

    2013-01-01

    Although member states are obliged to transpose directives into domestic law in a conformable manner and receive considerable time for their transposition activities, we identify three levels of transposition outcomes for EU directives: conformable, partially conformable and non-conformable....... Compared with existing transposition models, which do not distinguish between different transposition outcomes, we examine the factors influencing each transposition process by means of a competing risk analysis. We find that preference-related factors, in particular the disagreement of a member state...... and the Commission regarding a directive’s outcome, play a much more strategic role than has to date acknowledged in the transposition literature. Whereas disagreement of a member state delays conformable transposition, it speeds up non-conformable transposition. Disagreement of the Commission only prolongs...

  18. Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta

    Directory of Open Access Journals (Sweden)

    Zbigniew Pruszak

    2005-09-01

    Full Text Available The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions. One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam, the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland. The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.

  19. Intrahepatic Transposition of Bile Ducts

    Science.gov (United States)

    Delić, Jasmin; Savković, Admedina; Isaković, Eldar; Marković, Sergije; Bajtarevic, Alma; Denjalić, Amir

    2012-01-01

    Objective. To describe the intrahepatic bile duct transposition (anatomical variation occurring in intrahepatic ducts) and to determine the frequency of this variation. Material and Methods. The researches were performed randomly on 100 livers of adults, both sexes. Main research methods were anatomical macrodissection. As a criterion for determination of variations in some parts of bile tree, we used the classification of Segmentatio hepatis according to Couinaud (1957) according to Terminologia Anatomica, Thieme Stuugart: Federative Committee on Anatomical Terminology, 1988. Results. Intrahepatic transposition of bile ducts was found in two cases (2%), out of total examined cases (100): right-left transposition (right segmental bile duct, originating from the segment VIII, joins the left liver duct-ductus hepaticus sinister) and left-right intrahepatic transposition (left segmental bile duct originating from the segment IV ends in right liver duct-ductus hepaticus dexter). Conclusion. Safety and success in liver transplantation to great extent depends on knowledge of anatomy and some common embryological anomalies in bile tree. Variations in bile tree were found in 24–43% of cases, out of which 1–22% are the variations of intrahepatic bile ducts. Therefore, good knowledge on ductal anatomy enables good planning, safe performance of therapeutic and operative procedures, and decreases the risk of intraoperative and postoperative complications. PMID:22550601

  20. Bounded Rationality in Transposition Processes

    DEFF Research Database (Denmark)

    Vollaard, Hans; Martinsen, Dorte Sindbjerg

    2014-01-01

    perspective may affect the commonly employed explanatory factors of administrative capacities, misfit and the heterogeneity of preferences among veto players. To prevent retrospective rationalisation of the transposition process, this paper traces this process as it unfolded in Denmark and the Netherlands...

  1. Climatic variability between SST and river discharge at Amazon region

    Science.gov (United States)

    Silva, M. E.; Silva, E. R. L.

    2012-04-01

    Climatic variability, related both to precipitation and river discharge, has been associated to ocean variability. Authors commonly relate Pacific sea surface temperature (SST) variation to South America (SA) precipitation. Zonal displacement of Walker cell, with intensified subsidence over northern portion of SA, Subtropical Jet strengthening/weakening over extratropical latitudes of SA are, respectively, dynamical reasons scientifically accepted for increasing and depletion of precipitation at the respective areas. Many studies point out the influence of tropical Atlantic SST anomalies in relation to precipitation/river discharge variability over northeast of Brazil. Aliseos variability at tropical Atlantic is also a physic process that contributes to explain precipitation and river flow variability over SA, mainly over the north portion. In this study, we aim to investigate the temporal correlation between SST, mainly from Pacific and Atlantic oceans, and rivers discharge at the Amazon region. Ji-Parana, Madeira and Tapajós river discharge in monthly and annual scale, between 1968 and 2008, were the time series selected to reach the purpose. Time series for river discharge were obtained from Agência Nacional de Águas (ANA, in Portuguese) and, SST data were obtained from CDC/NOAA. Before linear correlation computations between river discharge and SST have been made, seasonal cycle and linear tendency were removed from all original time series. Areas better correlated to river discharge at Amazon region show oceanic patterns apparently associated to PDO (Pacific Decadal Oscillation) and ENSO (El Niño-South Oscillation) variability, with absolute values greater than 0.3 and reaching 0.5 or 0.6. The spatial pattern observed at Pacific basin is similar to that showed by the first mode of PCA (Principal Component Analysis), such seen in many studies (the "horse shoe" pattern). In general, negative correlation values appear far more to the west of Pacific basin

  2. Sleeping Beauty transposition: from biology to applications.

    Science.gov (United States)

    Narayanavari, Suneel A; Chilkunda, Shreevathsa S; Ivics, Zoltán; Izsvák, Zsuzsanna

    2017-02-01

    Sleeping Beauty (SB) is the first synthetic DNA transposon that was shown to be active in a wide variety of species. Here, we review studies from the last two decades addressing both basic biology and applications of this transposon. We discuss how host-transposon interaction modulates transposition at different steps of the transposition reaction. We also discuss how the transposon was translated for gene delivery and gene discovery purposes. We critically review the system in clinical, pre-clinical and non-clinical settings as a non-viral gene delivery tool in comparison with viral technologies. We also discuss emerging SB-based hybrid vectors aimed at combining the attractive safety features of the transposon with effective viral delivery. The success of the SB-based technology can be fundamentally attributed to being able to insert fairly randomly into genomic regions that allow stable long-term expression of the delivered transgene cassette. SB has emerged as an efficient and economical toolkit for safe and efficient gene delivery for medical applications.

  3. Partial Transposition on Bipartite System

    Institute of Scientific and Technical Information of China (English)

    REN Xi-Jun; HAN Yong-Jian; WU Yu-Chun; GUO Guang-Can

    2008-01-01

    Many properties of partial transposition are unclear as yet.Here we carefully consider the number of the negative eigenvalues of ρT(ρ's partial transposition)when ρ is a two-partite state.There is strong evidence to show that the number of negative eigenvalues of ρT is N(N-1)/2 at most when ρ is a state in Hilbert space CM(×)CN.For the special case,the 2×2 system,we use this result to give a partial proof of the conjecture |ρT|T≥0.We find that this conjecture is strongly connected with the entanglement of the state corresponding to the negative eigenvalue of ρT or the negative entropy of ρ.

  4. Regional economic impacts of Grand Canyon river runners.

    Science.gov (United States)

    Hjerpe, Evan E; Kim, Yeon-Su

    2007-10-01

    Economic impact analysis (EIA) of outdoor recreation can provide critical social information concerning the utilization of natural resources. Outdoor recreation and other non-consumptive uses of resources are viewed as environmentally friendly alternatives to extractive-type industries. While outdoor recreation can be an appropriate use of resources, it generates both beneficial and adverse socioeconomic impacts on rural communities. The authors used EIA to assess the regional economic impacts of rafting in Grand Canyon National Park. The Grand Canyon region of northern Arizona represents a rural US economy that is highly dependent upon tourism and recreational expenditures. The purpose of this research is twofold. The first is to ascertain the previously unknown regional economic impacts of Grand Canyon river runners. The second purpose is to examine attributes of these economic impacts in terms of regional multipliers, leakage, and types of employment created. Most of the literature on economic impacts of outdoor recreation has focused strictly on the positive economic impacts, failing to illuminate the coinciding adverse and constraining economic impacts. Examining the attributes of economic impacts can highlight deficiencies and constraints that limit the economic benefits of recreation and tourism. Regional expenditure information was obtained by surveying non-commercial boaters and commercial outfitters. The authors used IMPLAN input-output modeling to assess direct, indirect, and induced effects of Grand Canyon river runners. Multipliers were calculated for output, employment, and income. Over 22,000 people rafted on the Colorado River through Grand Canyon National Park in 2001, resulting in an estimated $21,100,000 of regional expenditures to the greater Grand Canyon economy. However, over 50% of all rafting-related expenditures were not captured by the regional economy and many of the jobs created by the rafting industry are lower-wage and seasonal. Policy

  5. Simulating river discharge in a snowy region of Japan using output from a regional climate model

    Science.gov (United States)

    Ma, X.; Kawase, H.; Adachi, S.; Fujita, M.; Takahashi, H. G.; Hara, M.; Ishizaki, N.; Yoshikane, T.; Hatsushika, H.; Wakazuki, Y.; Kimura, F.

    2013-07-01

    Snowfall amounts have fallen sharply along the eastern coast of the Sea of Japan since the mid-1980s. Toyama Prefecture, located approximately in the center of the Japan Sea region, includes high mountains of the northern Japanese Alps on three of its sides. The scarcity of meteorological observation points in mountainous areas limits the accuracy of hydrological analysis. With the development of computing technology, a dynamical downscaling method is widely applied into hydrological analysis. In this study, we numerically modeled river discharge using runoff data derived by a regional climate model (4.5-km spatial resolution) as input data to river networks (30-arcseconds resolution) for the Toyama Prefecture. The five main rivers in Toyama (the Oyabe, Sho, Jinzu, Joganji, and Kurobe rivers) were selected in this study. The river basins range in area from 368 to 2720 km2. A numerical experiment using climate comparable to that at present was conducted for the 1980s and 1990s. The results showed that seasonal river discharge could be represented and that discharge was generally overestimated compared with measurements, except for Oyabe River discharge, which was always underestimated. The average correlation coefficient for 10-year average monthly mean discharge was 0.8, with correlation coefficients ranging from 0.56 to 0.88 for all five rivers, whereas the Nash-Sutcliffe efficiency coefficient indicated that the simulation accuracy was insufficient. From the water budget analysis, it was possible to speculate that the lack of accuracy of river discharge may be caused by insufficient accuracy of precipitation simulation.

  6. Lateralization Technique and Inferior Alveolar Nerve Transposition

    Directory of Open Access Journals (Sweden)

    Angélica Castro Pimentel

    2016-01-01

    Full Text Available Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics.

  7. Lateralization Technique and Inferior Alveolar Nerve Transposition

    Science.gov (United States)

    Sanches, Marco Antonio; Ramalho, Gabriel Cardoso; Manzi, Marcello Roberto

    2016-01-01

    Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics. PMID:27433360

  8. An association between sella turcica bridging and dental transposition.

    Science.gov (United States)

    Leonardi, Rosalia; Farella, Mauro; Cobourne, Martyn T

    2011-08-01

    The aim of the present study was to determine any association between tooth transposition and bridging of the sella turcica, given the evidence of common embryonic origins associated with these structures and a genetic basis underlying these two conditions. Clinical records of subjects demonstrating dental transposition and normal controls were collected from several hospital orthodontic departments and specialist orthodontic practices. All cases and controls were documented with good quality lateral cephalometric radiographs and dental panoramic tomograms (DPTs). The study sample consisted of 21 Caucasian subjects (7 males and 14 females; mean age 14.5 years; SD 2.2 years), demonstrating either maxillary or mandibular dental transposition. The control group, matched for age and gender to the study sample, comprised 70 Caucasians (31 males and 39 females; mean age 13.8 years; SD 1.8 years) without dental anomalies randomly selected from subjects referred for orthodontic treatment within the same departments. The extent of sella turcica bridging was quantified from each profile radiograph using comparative measurement of length and diameter. Sella turcica bridging was found more frequently in subjects diagnosed with dental transposition than in the controls, with the difference being statistically significant [chi-square=7.4; degrees of freedom (df)=2; P=0.025; Fisher's exact test; P=0.042]. The increased frequency of complete and partial bridging of the sella turcica in subjects with dental transposition provides further evidence of a genetic basis to this condition. As calcification and bridging of this region can present during early childhood, it may act as a useful diagnostic predictor of susceptibility to local dental problems.

  9. Syllable Transposition Effects in Korean Word Recognition

    Science.gov (United States)

    Lee, Chang H.; Kwon, Youan; Kim, Kyungil; Rastle, Kathleen

    2015-01-01

    Research on the impact of letter transpositions in visual word recognition has yielded important clues about the nature of orthographic representations. This study investigated the impact of syllable transpositions on the recognition of Korean multisyllabic words. Results showed that rejection latencies in visual lexical decision for…

  10. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK.

    Science.gov (United States)

    Shepherd, Thomas J; Chenery, Simon R N; Pashley, Vanessa; Lord, Richard A; Ander, Louise E; Breward, Neil; Hobbs, Susan F; Horstwood, Matthew; Klinck, Benjamin A; Worrall, Fred

    2009-08-15

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ((208)Pb/(206)Pb, (207)Pb/(206)Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ((208)Pb/(206)Pb, (207)Pb/(206)Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  11. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Chenery, Simon R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Pashley, Vanessa [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Lord, Richard A. [School of Science and Technology, University of Teesside, Middlesbrough, Tees Valley TS1 3BA (United Kingdom); Ander, Louise E.; Breward, Neil; Hobbs, Susan F. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Horstwood, Matthew [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Klinck, Benjamin A. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Worrall, Fred [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom)

    2009-08-15

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  12. Transposition and national level resources

    DEFF Research Database (Denmark)

    Vasev, Nikolay Rumenov; Vrangbæk, Karsten

    2014-01-01

    Several recent papers have summarised the status of EU implementation studies. In this paper we suggest that the issue of sector specific resources has received too little attention in previous studies. Sector specific resources include “health sector resources” and “state administrative resources......”. Our theoretical contribution is thus to add an explicit and more detailed concern for "sector specific resources" in national transposition. This can refine the understanding of resources, for example in the multi-variable models that are emerging as the state of the art in the field of EU...... implementation studies. To illustrate these points we have chosen an empirical design focusing on a directive with a potentially high impact on system resources and several ambiguous components (the Cross Border Health Care Directive). We have further chosen to focus on two Eastern European countries (Bulgaria...

  13. Transpositional behaviour of the Ds element in the Ac/Ds system in rice

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Insertional mutagenesis based on maize Activator/Dissociator (Ac/Ds) transposons is becoming a major approach used to produce a saturated mutant collection in rice. In this research, Ds-T-DNA transformed homozygotes were crossed with Ac-T-DNA transformed homozygotes in order to establish an Ac/Ds transposon system in rice. The successive investigation of Ds transposition from F1 to F5 generations indicated that the frequencies of germinal transposition increased over successive generations and reached 54.2% in F3 generation. The Ds transposition pattern revealed that a Ds transposition induced an approximately 170-bp deletion of T-DNA sequence and another Ds transposition carried a 272-bp T-DNA sequence. Using thermal asymmetric interlaced PCR (TAIL-PCR), some flanking sequences of the Ds element were amplified. Analyses of 17 Ds-flanking sequences showed that five Ds were inserted into gene regions. The Ds could transpose not only to the linked sites but also to the unlinked sites. The frequency of inter-chromosomal transposition of Ds was 33.3%.

  14. Parallel transposition of sparse data structures

    DEFF Research Database (Denmark)

    Wang, Hao; Liu, Weifeng; Hou, Kaixi

    2016-01-01

    Many applications in computational sciences and social sciences exploit sparsity and connectivity of acquired data. Even though many parallel sparse primitives such as sparse matrix-vector (SpMV) multiplication have been extensively studied, some other important building blocks, e.g., parallel...... transposition for sparse matrices and graphs, have not received the attention they deserve. In this paper, we first identify that the transposition operation can be a bottleneck of some fundamental sparse matrix and graph algorithms. Then, we revisit the performance and scalability of parallel transposition...... approaches on x86-based multi-core and many-core processors. Based on the insights obtained, we propose two new parallel transposition algorithms: ScanTrans and MergeTrans. The experimental results show that our ScanTrans method achieves an average of 2.8-fold (up to 6.2-fold) speedup over the parallel...

  15. Maxillary canine-to-maxillary incisor transposition.

    Science.gov (United States)

    Lin, Yng-Tzer J

    2013-01-01

    Dental transposition is the positional interchange of two adjacent teeth. Canine transpositions are usually accompanied by other dental anomalies, such as: impaction of the incisors; missing teeth; peg-shaped lateral incisors; severe rotation or malposition of adjacent teeth; dilacerations; and malformations. Local pathologic processes, such as tumors, cysts, retained primary canines, and supernumerary teeth, might be responsible for canine transposition. The purpose of this paper was to present a rare case of maxillary canine-to-maxillary incisor transposition in an 8-year-old girl. The patient presented with noneruption of the permanent maxillary left central incisor, and a radiographic examination revealed an impacted dilacerated incisor. The central incisor was extracted because the root was severely dilacerated. At the 3-year follow-up, an oral examination revealed that the canine had transposed to the extraction site. Through orthodontic traction, combined with reshaping of the tooth, the transposed canine was successfully positioned into the incisor position.

  16. Minimal factorizations of permutations into star transpositions

    OpenAIRE

    Irving, J.; Rattan, Amarpreet

    2009-01-01

    International audience; We give a compact expression for the number of factorizations of any permutation into a minimal number of transpositions of the form $(1 i)$. Our result generalizes earlier work of Pak ($\\textit{Reduced decompositions of permutations in terms of star transpositions, generalized catalan numbers and k-ary trees}$, Discrete Math. $\\textbf{204}$:329―335, 1999) in which substantial restrictions were placed on the permutation being factored.; Nous présentons une expression c...

  17. Transposition of the great arteries

    Directory of Open Access Journals (Sweden)

    Castela Eduardo

    2008-10-01

    Full Text Available Abstract Transposition of the great arteries (TGA, also referred to as complete transposition, is a congenital cardiac malformation characterised by atrioventricular concordance and ventriculoarterial (VA discordance. The incidence is estimated at 1 in 3,500–5,000 live births, with a male-to-female ratio 1.5 to 3.2:1. In 50% of cases, the VA discordance is an isolated finding. In 10% of cases, TGA is associated with noncardiac malformations. The association with other cardiac malformations such as ventricular septal defect (VSD and left ventricular outflow tract obstruction is frequent and dictates timing and clinical presentation, which consists of cyanosis with or without congestive heart failure. The onset and severity depend on anatomical and functional variants that influence the degree of mixing between the two circulations. If no obstructive lesions are present and there is a large VSD, cyanosis may go undetected and only be perceived during episodes of crying or agitation. In these cases, signs of congestive heart failure prevail. The exact aetiology remains unknown. Some associated risk factors (gestational diabetes mellitus, maternal exposure to rodenticides and herbicides, maternal use of antiepileptic drugs have been postulated. Mutations in growth differentiation factor-1 gene, the thyroid hormone receptor-associated protein-2 gene and the gene encoding the cryptic protein have been shown implicated in discordant VA connections, but they explain only a small minority of TGA cases. The diagnosis is confirmed by echocardiography, which also provides the morphological details required for future surgical management. Prenatal diagnosis by foetal echocardiography is possible and desirable, as it may improve the early neonatal management and reduce morbidity and mortality. Differential diagnosis includes other causes of central neonatal cyanosis. Palliative treatment with prostaglandin E1 and balloon atrial septostomy are usually

  18. Mercury pollution in Rana Chensinensis in Weisha River reach, in the upstream region of Songhua River

    Institute of Scientific and Technical Information of China (English)

    WANG Ning; ZHU Yanming; SHENG Lianxi; MENG Dan

    2005-01-01

    Twice a year continuous samples of Rana Chensinensis and sediments have been collected near gold mine in the upstream region of Songhua River from 2000 to 2002, for analyzing the total mercury (THg), methylmercury (MeHg) concentration and correlation in sediments, muscles, livers of the frog. The study indicates that THg and MeHg concentrations in polluted samples near the gold mine are higher than those in unpolluted ones. THg and MeHg concentrations are higher in autumn, in female, and in livers than those in spring, in male, in muscles respectively. The order of concentration degree in the frog organizations is as follows: liver>muscle>ovum>Fallopian tube. MeHg is the main form of mercury (Hg) existing in autumn, while inorganic Hg is in spring. There is no distinct difference of CMeHg/CTHg between male and female, livers and muscles. The correlation between MeHg concentrations in the river sediments and in the frog's livers and muscles are significant, which is related to disorderly discharge of Hg.

  19. Climate transformation to warm-humid and its effect on river runoff in the source region of the Yellow River

    Institute of Scientific and Technical Information of China (English)

    YongChao Lan; HuiJun Jin; ChengFang La; Jun Wen; Jie Song; JinPeng Liu

    2014-01-01

    The change characteristics and trends of the regional climate in the source region of the Yellow River, and the response of runoff to climate change, are analyzed based on observational data of air temperature, precipitation, and runoff at 10 main hydrological and weather stations in the region. Our results show that a strong signal of climate shift from warm-dry to warm-humid in the western parts of northwestern China (Xinjiang) and the western Hexi Corridor of Gansu Province occurred in the late 1980s, and a same signal of climate change occurred in the mid-2000s in the source region of the Yellow River located in the eastern part of northwestern China. This climate changeover has led to a rapid increase in rainfall and stream runoff in the latter region. In most of the years since 2004 the average annual precipitation in the source region of the Yellow River has been greater than the long-term average annual value, and after 2007 the runoff measured at all of the hydrologic sections on the main channel of the Yellow River in the source region has also consistently exceeded the long-term average annual because of rainfall increase. It is difficult to determine the prospects of future climate change until additional observations and research are conducted on the rate and temporal and spatial extents of climate change in the region. Nevertheless, we predict that the climate shift from warm-dry to warm-humid in the source region of the Yellow River is very likely to be in the decadal time scale, which means a warming and rainy climate in the source region of the Yellow River will continue in the coming decades.

  20. Regional variation of sediment load of Asian rivers flowing into the ocean

    Institute of Scientific and Technical Information of China (English)

    刘曙光; 丁坚; 华棣; 杨洪林; 李从先; 杨守业

    2001-01-01

    Study of Asian major rivers discharge to the ocean reveals variations of their water discharges and sediment loads, and local characteristic of river sediment concentrations. On the basis of this, the Asian rivers can be divided into three regions: Eurasia Arctic, East Asia, Southeast and South Asia Region. The Eurasia Arctic Region is characteristic of the lowest sediment concentration and load, while the East Asia Region is of the highest sediment concentration and higher sediment load, and the Southeast and South Asia Region yields higher sediment concentration and highest sediment load.

  1. Application of ovarian transposition during hysterectomy

    Institute of Scientific and Technical Information of China (English)

    郭毅; 沈文静; 姜艳明; 刘伟; 李秀芬

    2003-01-01

    Objective To study the optimal position and method for ovarian transposition and its benefits and indications.Methods We performed ovarian transposition in 34 patients from August 1989 to December 2000. Twelve patients were diagnosed with stage Ⅰb to Ⅱa cervical cancer, 4 had stage Ⅰa endometrial carcinoma, 12 had stage Ⅲ to Ⅳ endometriosis, 4 had myoma of uterus, 1 had dysfunctional uterine bleeding, and 1 had an ovarian granulosa cell tumor. Surgery went as follows: the ovary was dissociated by clamp, the skin was incised and a tunnel was made, then the ovary was translocated to the subcutaneous site. In the cases of benign lesions, the ovarian vessel pedicel went in through the abdominal cavity, but in malignant tumors, it went out through the peritoneum. Results In both cases (benign lesions or malignant tumors), the short-term and long-term endocrine function of the translocated ovary remained normal. Furthermore, patients could supervise their translocated ovary themselves.Conclusions Subcutaneous ovary transposition might prevent not only implantation of gastrointestinal cancer but also the extension of pelvic carcinoma to the ovary. Because of the shallow transposition and the incision scar, it is easy for patients to supervise themselves. Moreover, the site of the ovary is easy to locate for ultrasound examinations. Thus, it can obtain the goal of early prevention for cancer. Subcutaneous ovarian transposition with skin incision is the optimal selection and suitable for all patients with various gynecologic diseases in which ovary removal is not necessary.

  2. Contamination profiles of perfluoroalkyl substances in five typical rivers of the Pearl River Delta region, South China.

    Science.gov (United States)

    Pan, Chang-Gui; Ying, Guang-Guo; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Peng, Feng-Jiao; Huang, Guo-Yong

    2014-11-01

    A survey on contamination profiles of eighteen perfluoroalkyl substances (PFASs) was performed via high performance liquid chromatography-tandem mass spectrometry for surface water and sediments from five typical rivers of the Pearl River Delta region, South China in summer and winter in 2012. The total concentrations of the PFASs in the water phase of the five rivers ranged from 0.14 to 346.72 ng L(-1). The PFAS concentrations in the water phase were correlated positively to some selected water quality parameters such as chemical oxygen demand (COD) (0.7913) and conductivity (0.5642). The monitoring results for the water samples showed significant seasonal variations, while those for the sediment samples showed no obvious seasonal variations. Among the selected 18 PFASs, perfluorooctane sulfonic acid (PFOS) was the dominant PFAS compound both in water and sediment for two seasons with its maximum concentration of 320.5 ng L(-1) in water and 11.4 ng g(-1) dry weight (dw) in sediment, followed by perfluorooctanoic acid (PFOA) with its maximum concentration of 26.48 ng L(-1) in water and 0.99 ng g(-1) dw in sediment. PFOS and PFOA were found at relatively higher concentrations in the Shima River and Danshui River than in the other three rivers (Xizhijiang River, Dongjiang River and Shahe River). The principal component analysis for the PFASs concentrations in water and sediment separated the sampling sites into two groups: rural and agricultural area, and urban and industrial area, suggesting the PFASs in the riverine environment were mainly originated from industrial and urban activities in the region.

  3. Sediment Load of Asian Rivers flowing into the Oceans and their Regional Variation

    Institute of Scientific and Technical Information of China (English)

    Liu Shuguang; Zheng Yonglai; Zhuge Zhengji; Li Congxian

    2002-01-01

    Study of the major Asian rivers discharge to the ocean reveals variations of their water discharges and sediment loads, and local characteristics of river sediment concentrations. On the basis of this, the Asian rivers fall into three regions, including Eurasia Arctic, East Asia, Southeast and South Asia Regions. The Eurasia Arctic Region is characterized by the lowest sediment concentration and load, while the East Asia Region is of the highest sediment concentration and higher sediment load, and the South-East and South Asia Region yields higher sediment concentration and highest sediment load.The sediment loads of these regions are mainly controlled by climate, geomorphology and tectonic activity. The Eurasia Arctic rivers with large basin areas and water discharge, drain low relief which consists of tundra sediment, thus causing the lowest sediment load. The East Asia rivers with small basin areas and lowest water discharges, drain extensive loess plateau, and transport most erodible loess material, which results in highest sediment concentration. The SE and South Asia rivers originating from the Tibet Plateau have large basin areas and the largest water discharges because of the Summer Monsoon and high rainfall influence, causing the highest sediment load.In Asia, tectonic motion of the Tibet Plateau plays an important role. Those large rivers originating from the Tibet Plateau transport about 50% of the world river sediment load to ocean annually, forming large estuaries and deltas, and consequently exerting a great influence on sedimentation in the coastal zone and shelves.

  4. 27 CFR 9.47 - Hudson River Region.

    Science.gov (United States)

    2010-04-01

    ... to the New York-Pennsylvania state line in the Delaware River. (11) The boundary proceeds easterly along the Delaware River to the New York-New Jersey state line. (12) The boundary proceeds easterly... proceeds easterly along the northern side of Interstate Route 287 to the junction with N.Y. Route 15....

  5. Pig transgenesis by Sleeping Beauty DNA transposition

    DEFF Research Database (Denmark)

    Jakobsen, Jannik E.; Li, Juan; Kragh, Peter M.

    2011-01-01

    disease models. In this report, we present transgenic pigs created by Sleeping Beauty DNA transposition in primary porcine fibroblasts in combination with somatic cell nuclear transfer by handmade cloning. Göttingen minipigs expressing green fluorescent protein are produced by transgenesis with DNA...... plasmid DNA. Our findings illustrate critical issues related to DNA transposon-directed transgenesis, including coincidental plasmid insertion and relatively low Sleeping Beauty transposition activity in porcine fibroblasts, but also provide a platform for future development of porcine disease models...... using the Sleeping Beauty gene insertion technology....

  6. Regional and local new particle formation events observed in the Yangtze River Delta region, China

    Science.gov (United States)

    Dai, Liang; Wang, Honglei; Zhou, Luyu; An, Junlin; Tang, Lili; Lu, Chunsong; Yan, Wenlian; Liu, Ruiyang; Kong, Shaofei; Chen, Mindong; Lee, Shanhu; Yu, Huan

    2017-02-01

    To study the spatial inhomogeneity of new particle formation (NPF) in the polluted atmosphere of China, we conducted simultaneous measurements at an urban site near a petrochemical industrial area and a regional background site in the Yangtze River Delta region from September to November 2015. At the urban site we observed a type of local NPF event (number of events: n = 5), in which nucleation was limited to a small area but persisted for 6.8 h on average during the daytime. Formation rates of 5 nm particles (J5) were found to be correlated positively with the H2SO4 proxy (log J5 versus log[H2SO4] slope near 1) in both local and regional events. Furthermore, J5 was enhanced by the anthropogenic volatile organic carbon (VOC) plumes from nearby industrial area in the local events compared to the regional events. Size-dependent aerosol dynamics calculation showed that in comparison with the observed regional events, the local events were featured with high nucleation rate (J1.3 > 1000 cm-3 s-1), high growth rate of sub-3 nm particles (GRsub-3 > 20 nm h-1), and high number concentration of nucleation mode particles (mean peak N5-20: 6 × 104 cm-3). Considering these features, the local NPF events of anthropogenic origin may also be an important contributor to cloud condensation nuclei concentrations in urban and regional scales. In addition, the comparison of simultaneous regional NPF events between the two sites (number of events: n = 7) suggested that regional NPF intensity may be underestimated by the single-point measurement at an urban site, due to the heterogeneity of air masses.

  7. Analysis of the ancient river system in Loulan period in Lop Nur region

    Science.gov (United States)

    Zhu, Jianfeng; Jia, Peng; Nie, Yueping

    2010-09-01

    The Lop Nur region is located in the east of the Tarim Basin. It has served as the strategic passage and communication hub of the Silk Road since Han Dynasty. During Wei-Jin period, the river system there was well developed and the ancient city of Loulan was bred there. In this study, GIS is used to accomplish automatic extraction of the river course in the Lop Nur region at first using ArcGIS. Then the RCI index is constituted to extract ancient river course from Landsat ETM image with band 3 and band 4. It is concluded that the north river course of Peacock River conformed before the end of the 4th century AD according to the distribution of the entire river course of the Lop Nur region. Later, the Peacock River changed its way to south to Tarim River, and flowed into Lop Nur along the direction paralleling Altun Mountain from west to east. It was the change of the river system that mainly caused the decrease in water supply around ancient city of Loulan before the end of 4th century. The ancient city of Loulan has been gradually ruined in the sand because of the absence of water supply since then.

  8. Water quality evaluation of Himalayan Rivers of Kumaun region, Uttarakhand, India

    Science.gov (United States)

    Seth, Richa; Mohan, Manindra; Singh, Prashant; Singh, Rakesh; Dobhal, Rajendra; Singh, Krishna Pal; Gupta, Sanjay

    2016-06-01

    Water quality of Himalayan rivers has been steadily deteriorating over several decades due to anthropogenic activities, dumping of treated or untreated effluents, poor structured sewerage and drainage system, etc. In the present study, the water quality of five important rivers namely, Gola, Kosi, Ramganga, Saryu and Lohawati rivers were investigated which flow through the different districts of Kumaun region of Uttarakhand Himalaya. The water of all these rivers serves as the major source for drinking and irrigation purposes in these districts of the Kumaun region of Uttarakhand. River water samples collected in pre-monsoon and post-monsoon seasons of the years 2011 and 2012 were analyzed for various water quality characteristics. Statistical analyses indicate positive correlation among most of the chemical parameters. Piper diagram illustrates that all the water samples fall in Ca-Mg-HCO3 hydrochemical facies, Moreover, the suitability of water for drinking purposes determined by water quality index indicated that river water in both the seasons is unsuitable. Irrigation water quality of all the river water was found suitable during both the seasons according to the result of sodium adsorption ratio, sodium percentage and residual sodium carbonate. The present study revealed that major factors contributing to deterioration of water quality of all the rivers might be eutrophication, tourism, anthropogenic and geogenic processes. Therefore, to restore the vitality and water quality of all these rivers, proper water resource planning programme should be developed.

  9. Regional economic analysis of current and proposed management alternatives for Rappahannock River Valley National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this study was to assess the regional economic implications associated with draft CCP management strategies for Rappahannock River Valley NWR. This...

  10. Building a competitive Pearl River Delta region: cooperation, coordination, and planning

    OpenAIRE

    2002-01-01

    Papers mainly originated from the Seminar on Building a Competitive Pearl River Delta Region: Cooperation, Coordination and planning held on 8 July 2000 at the Hong Kong Convention and Exhibition Centre

  11. Organization of tn2610 containing two transposition modules.

    Science.gov (United States)

    Takaya, Akiko; Watanabe, Masato; Yamamoto, Tomoko

    2006-04-01

    Transposon Tn2610, found in a conjugative plasmid from an Escherichia coli isolate recovered at a hospital in Chiba, Japan, in 1975, was completely sequenced. Tn2610 is 23,883 bp long and is bracketed by two transposition modules, a Tn1721-like module and a Tn21-derived module, which correspond, respectively, to the long inverted repeats IRa and IRb previously described for this transposon. Although both tnpA genes are intact, only that in the Tn21-derived module (IRb) functions in the transposition, while that in the Tn1721-derived module (IRa) cannot recognize the 38-bp imperfect repeat at the end of the IRb element. Both tnpR and res are present in IRa, while the tnpR gene of IRb is interrupted by the insertion of an IS26 insertion element. The intervening region, between the res site of the Tn1721 module and IS26, carries multiple integron-associated resistance genes within a Tn21 backbone, including a region identical to that found in the genome of Salmonella enterica serovar Typhimurium DT104. These findings suggest that Tn2610 originated from Tn1721 and Tn21, with extensive recombination events with other elements which have resulted in a complex mosaic structure.

  12. Process analysis of regional aerosol pollution during spring in the Pearl River Delta region, China

    Science.gov (United States)

    Fan, Qi; Lan, Jing; Liu, Yiming; Wang, Xuemei; Chan, Pakwai; Hong, Yingying; Feng, Yerong; Liu, Yexin; Zeng, Yanjun; Liang, Guixiong

    2015-12-01

    A numerical simulation analysis was performed for three air pollution episodes in the Pearl River Delta (PRD) region during March 2012 using the third-generation air quality modeling system Models-3/CMAQ. The results demonstrated that particulate matter was the primary pollutant for all three pollution episodes and was accompanied by relatively low visibility in the first two episodes. Weather maps indicate that the first two episodes occurred under the influence of warm, wet southerly air flow systems that led to high humidity throughout the region. The liquid phase reaction of gaseous pollutants resulted in the generation of fine secondary particles, which were identified as the primary source of pollution in the first two episodes. The third pollution episode occurred during a warming period following a cold front. Relative humidity was lower during this episode, and coarse particles were the major pollution contributor. Results of process analysis indicated that emissions sources, horizontal transport and vertical transport were the primary factors affecting pollutant concentrations within the near-surface layer during all three episodes, while aerosol processes, cloud processes, horizontal transport and vertical transport had greater influence at approximately 900 m above ground. Cloud processes had a greater impact during the first two pollution episodes because of the higher relative humidity. In addition, by comparing pollution processes from different cities (Guangzhou and Zhongshan), the study revealed that the first two pollution episodes were the result of local emissions within the PRD region and transport between surrounding cities, while the third episode exhibited prominent regional pollution characteristics and was the result of regional pollutant transport.

  13. Ecological restoration and effect investigation of a river wetland in a semi-arid region, China

    Science.gov (United States)

    Xu, S.; Jiang, X.; Liu, Y.; Fu, Y.; Zhao, Q.

    2015-05-01

    River wetlands are heavily impacted by human intervention. The degradation and loss of river wetlands has made the restoration of river ecosystems a top priority. How to rehabilitate rivers and their services has been a research focus. The main goal of it is to restore the river wetland ecosystems with ecological methods. The Gudong River was selected as a study site in Chaoyang city in this study. Based on the analysis of interference factors in the river wetland degradation, a set of restoration techniques were proposed and designed for regional water level control, including submerged dikes, ecological embankments, revegetation and dredging. The restoration engineering has produced good results in water quality, eco-environment, and landscape. Monthly reports of the Daling River show that the water quality of Gudong River was better than Grade III in April 2013 compared with Grade V in May 2012. The economic benefit after restoration construction is 1.71 million RMB per year, about 1.89 times that before. The ratio of economic value, social value and eco-environmental value is 1:4:23.

  14. Modeling of Regionalized Emissions (MoRE) into Water Bodies: An Open-Source River Basin Management System

    National Research Council Canada - National Science Library

    Stephan Fuchs; Maria Kaiser; Lisa Kiemle; Steffen Kittlaus; Shari Rothvoß; Snezhina Toshovski; Adrian Wagner; Ramona Wander; Tatyana Weber; Sara Ziegler

    2017-01-01

    .... The river basin management system MoRE (Modeling of Regionalized Emissions) was developed as a flexible open-source instrument which is able to model pathway-specific emissions and river loads on a catchment scale...

  15. Database Transposition for Constrained (Closed) Pattern Mining

    CERN Document Server

    Jeudy, Baptiste

    2009-01-01

    Recently, different works proposed a new way to mine patterns in databases with pathological size. For example, experiments in genome biology usually provide databases with thousands of attributes (genes) but only tens of objects (experiments). In this case, mining the "transposed" database runs through a smaller search space, and the Galois connection allows to infer the closed patterns of the original database. We focus here on constrained pattern mining for those unusual databases and give a theoretical framework for database and constraint transposition. We discuss the properties of constraint transposition and look into classical constraints. We then address the problem of generating the closed patterns of the original database satisfying the constraint, starting from those mined in the "transposed" database. Finally, we show how to generate all the patterns satisfying the constraint from the closed ones.

  16. Transpositional flap technique for mandibular vestibuloplasty.

    Science.gov (United States)

    Wessberg, G A; Hill, S C; Epker, B N

    1979-06-01

    Various surgical techniques for a mandibular vestibuloplasty have been advocated. A transpositional labial flap technique used by us for 23 patients since May 1976, and based on a procedure described by Edlan, has been presented with results of nine-month follow-up examinations of six patients. Clinical, radiographic, and histological evaluations completed at three-month intervals showed that this transpositional vestibuloplasty compared favorably with other similar techniques in postoperative time of healing, condition of attached mucosa, stability of increased vestibular depth, and amount of resorption of labial bone. Advantages of this procedure over other mandibular vestibuloplasty techniques are its simplicity, low morbidity, decreased operating time, feasibility of use of local anesthesia and conscious sedation on an outpatient basis, and elimination of the need for a graft. The disadvantage of the procedure is that it requires healthy preexisting vestibular mucosa for optimal results.

  17. STUDY OF LONG-TERM TREND IN RIVER DISCHARGE OF SUTLEJ RIVER (N-W HIMALAYAN REGION

    Directory of Open Access Journals (Sweden)

    Dharmaveer Singh

    2014-01-01

    Full Text Available Sutlej basin, a mountainous river basin is located in N-W Himalayan region. This basin has highest potential for hydropower generation as compared to other basins of Indus River system. Recent studies have revealed rise in mean annual surface temperature which will modify pattern of Sutlej River flow in this basin. The present paper has aimed for studying annual and seasonal patterns of river discharge at different gauging sites of Sutlej River basin (middle catchment, India. The study has been performed over three gauging sites, namely, Kasol, Sunni and Rampur located under different physiographic and climatic conditions. The daily historical records (1970-2010 of 41 years river discharge data have been employed for statistical analysis. The annual and seasonal Standardized Discharge Indices (SDI has been derived in order to preserve uniformity and facilitate comparison between flows of Sutlej River at different sites. Mann-Kendall (MK test, a non-parametric test method, has been applied to detect trend in annual and seasonal SDI for periods 1970-2010. Decadal (annual and seasonal patterns in SDI have also been discussed. The results of annual and seasonal trend analysis have revealed decreasing trends in SDI at all the gauging sites. The trend in annual SDI is statistically significant (95% confidence level at Rampur (0,04 cumec/year and insignificant at Kasol (0,02 cumec/year and Sunni (0,01 cumec/year respectively. The study of annual decadal change in SDI at all the sites shows that reduction in river discharge has occurred in the decade of 2001-2010. Before this, continuous rise in annual discharge has been reported at all the sites from decades 1970-1980 to the last decade of 20th century (1991-2000. The decline in river flow may affect agriculture and electricity production as well as there may be problems related with drinking water. The present study is expected to be useful for planning water resources related projects that can be

  18. Methodology to determine regional water demand for instream flow and its application in the Yellow River Basin

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuan; YANG Zhi-feng; Wang Xi-qin

    2006-01-01

    In order to realistically reflect the difference between regional water demand for instream flow and river ecological water demand as well as to resolve the problem that water demand may be counted repeatedly, a concept of regional water demand for minimum instream flow have been developed. The concept was used in the process of determining river functions and calculating ecological water demand for a river. The Yellow River watershed was used to validate the calculation methodology for regional water demand. Calculation results indicate that there are significant differences in water demands among the different regions. The regionalwater demand at the downstream of the Yellow River is the largest about 14.893 × 109 m3/a. The regional water demand of upstream,Lanzhou-Hekou section is the smallest about -5.012×109 m3/a. The total ecological water demand of the Yellow River Basin is 23.06 × 109 m3/a, about the 39% of surface water resources of the Yellow River Basin. That means the maximum available surface water resources should not exceed 61% in the Yellow River Basin. The regional river ecological water demands at the Lower Section of the Yellow River and Longyangxia-Lanzhou Section exceed the surface water resources produced in its region and need to be supplemented from other regions through the water rational planning of watershed water resources. These results provides technical basis for rational plan of water resources of the Yellow River Basin.

  19. Class of positive partial transposition states

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej

    2006-08-01

    We construct a class of quantum bipartite d⊗d states which are positive under partial transposition (PPT states). This class is invariant under the maximal commutative subgroup of U(d) and contains as special cases many well-known examples of PPT states. States from our class provide criteria for testing the indecomposability of positive maps. Such maps are crucial for constructing entanglement witnesses.

  20. Stabilized subcutaneous transposition of the ulnar nerve

    OpenAIRE

    2003-01-01

    We treated 50 patients (average age 47.9 years) with a stabilized subcutaneous transposition of the ulnar nerve. The average follow-up period was 42.4 months. The indication was cubital tunnel syndrome in 19 patients and injuries around the elbow in 31 patients. Postoperatively, satisfactory results were obtained in all the patients, and there was no complication or aggravation of the preoperative symptoms. None of the patients experienced slipping back of the nerve to the cubital tunnel. In ...

  1. Efects of Crop Growth on Hydrological Processes in River Basins and on Regional Climate in China

    Institute of Scientific and Technical Information of China (English)

    QIN; Pei-Hua; CHEN; Feng; XIE; Zheng-Hui

    2013-01-01

    The regional climate model RegCM3 incorporating the crop model CERES,called the RegCM3CERES model,was used to study the efects of crop growth and development on regional climate and hydrological processes over seven river basins in China.A 20-year numerical simulation showed that incorporating the crop growth and development processes improved the simulation of precipitation over the Haihe River Basin,Songhuajiang River Basin and Pearl River Basin.When compared with the RegCM3 control run,RegCM3CERES reduced the negative biases of monthly mean temperature over most of the seven basins in summer,especially the Haihe River Basin and Huaihe River Basin.The simulated maximum monthly evapotranspiration for summer(JJA)was around 100 mm in the basins of the Yangtze,Haihe,Huaihe and Pearl Rivers.The seasonal and annual variations of water balance components(runof,evapotranspiration and total precipitation)over all seven basins indicate that changes of evapotranspiration agree well with total precipitation.Compared to the RegCM3,RegCM3CERES simulations indicate reduced local water recycling rate over most of the seven basins due to lower evapotranspiration and greater water flux into these basins and an increased precipitation in the Heihe River Basin and Yellow River Basin,but reduced precipitation in the other five basins.Furthermore,a lower summer leaf area index(1.20 m2m 2),greater root soil moisture(0.01 m3m 3),lower latent heat flux(1.34 W m 2),and greater sensible heat flux(2.04 W m 2)are simulated for the Yangtze River Basin.

  2. Target Capture during Mos1 Transposition*

    Science.gov (United States)

    Pflieger, Aude; Jaillet, Jerôme; Petit, Agnès; Augé-Gouillou, Corinne; Renault, Sylvaine

    2014-01-01

    DNA transposition contributes to genomic plasticity. Target capture is a key step in the transposition process, because it contributes to the selection of new insertion sites. Nothing or little is known about how eukaryotic mariner DNA transposons trigger this step. In the case of Mos1, biochemistry and crystallography have deciphered several inverted terminal repeat-transposase complexes that are intermediates during transposition. However, the target capture complex is still unknown. Here, we show that the preintegration complex (i.e., the excised transposon) is the only complex able to capture a target DNA. Mos1 transposase does not support target commitment, which has been proposed to explain Mos1 random genomic integrations within host genomes. We demonstrate that the TA dinucleotide used as the target is crucial both to target recognition and in the chemistry of the strand transfer reaction. Bent DNA molecules are better targets for the capture when the target DNA is nicked two nucleotides apart from the TA. They improve strand transfer when the target DNA contains a mismatch near the TA dinucleotide. PMID:24269942

  3. Corrected transposition of the great arteries

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Hi; Park, Jae Hyung; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1981-12-15

    The corrected transposition of the great arteries is an usual congenital cardiac malformation, which consists of transposition of great arteries and ventricular inversion, and which is caused by abnormal development of conotruncus and ventricular looping. High frequency of associated cardiac malformations makes it difficult to get accurate morphologic diagnosis. A total of 18 cases of corrected transposition of the great arteries is presented, in which cardiac catheterization and angiocardiography were done at the Department of Radiology, Seoul National University Hospital between September 1976 and June 1981. The clinical, radiographic, and operative findings with the emphasis on the angiocardiographic findings were analyzed. The results are as follows: 1. Among 18 cases, 13 cases have normal cardiac position, 2 cases have dextrocardia with situs solitus, 2 cases have dextrocardia with situs inversus and 1 case has levocardia with situs inversus. 2. Segmental sets are (S, L, L) in 15 cases, and (I, D,D) in 3 cases and there is no exception to loop rule. 3. Side by side interrelationships of both ventricles and both semilunar valves are noticed in 10 and 12 cases respectively. 4. Subaortic type conus is noted in all 18 cases. 5. Associated cardic malformations are VSD in 14 cases, PS in 11, PDA in 3, PFO in 3, ASD in 2, right aortic arch in 2, tricuspid insufficiency, mitral prolapse, persistent left SVC and persistent right SVC in 1 case respectively. 6. For accurate diagnosis of corrected TGA, selective biventriculography using biplane cineradiography is an essential procedure.

  4. Uterine transposition: technique and a case report.

    Science.gov (United States)

    Ribeiro, Reitan; Rebolho, Juliano Camargo; Tsumanuma, Fernanda Keiko; Brandalize, Giovana Gugelmin; Trippia, Carlos Henrique; Saab, Karam Abou

    2017-08-01

    To report the first uterine transposition for fertility preservation in a patient with rectal cancer. Case report. Community hospital. A 26-year-old patient with stage cT3N1M0 rectal adenocarcinoma located 5 cm from the anal margin. Laparoscopic transposition of the uterus to the upper abdomen, outside of the scope of radiation, was performed to preserve fertility. After the end of radiotherapy, rectosigmoidectomy was performed and the uterus was repositioned into the pelvis. Uterine and ovarian function preservation. The patient had two menstrual periods and exhibited normal variation in ovarian hormones throughout the course of neoadjuvant therapy. Menstruation began 2 weeks after reimplantation into the pelvis, and the cervix exhibited a normal appearance on clinical examination after 6 weeks. Eighteen months after the surgery, the uterus was normal and there was no sign of disease. Uterine transposition might represent a valid option for fertility preservation in women who require pelvic radiotherapy and want to bear children. However, studies that assess its viability, effectiveness, and safety are required. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Groundwater Discharges to Rivers in the Western Canadian Oil Sands Region

    Science.gov (United States)

    Ellis, J.; Jasechko, S.

    2016-12-01

    Groundwater discharges into rivers impacts the movement and fate of nutrients and contaminants in the environment. Understanding groundwater-surface water interactions is especially important in the western Canadian oil sands, where groundwater contamination risks are elevated and baseline water chemistry data is lacking, leading to substantial uncertainties about anthropogenic influences on local river quality. High salinity groundwater springs sourced from deep aquifers, comprised of Pleistocene-aged glacial meltwater, are known to discharge into many rivers in the oil sands. Understanding connections between deep aquifers and surficial waterways is important in order to determine natural inputs into these rivers and to assess the potential for injected wastewater or oil extraction fluids to enter surface waters. While these springs have been identified, their spatial distribution along rivers has not been fully characterized. Here we present river chemistry data collected along a number of major river corridors in the Canadian oil sands region. We show that saline groundwater springs vary spatially along the course of these rivers and tend to be concentrated where the rivers incise Devonian- or Cretaceous-aged aquifers along an evaporite dissolution front. Our results suggest that water sourced from Devonian aquifers may travel through bitumen-bearing Cretaceous units and discharge into local rivers, implying a strong groundwater-surface water connection in specialized locations. These findings indicate that oil sands process-affected waters that are injected at depth have the potential to move through these aquifers and reach the rivers at the surface at some time in the future. Groundwater-surface water interactions remain key to understanding the risks oil sands activities pose to aquatic ecosystems and downstream communities.

  6. Regional Sediment Budget of the Columbia River Littoral Cell, USA

    Science.gov (United States)

    Buijsman, Maarten C.; Sherwood, C.R.; Gibbs, A.E.; Gelfenbaum, G.; Kaminsky, G.M.; Ruggiero, P.; Franklin, J.

    2002-01-01

    Summary -- In this Open-File Report we present calculations of changes in bathymetric and topographic volumes for the Grays Harbor, Willapa Bay, and Columbia River entrances and the adjacent coasts of North Beach, Grayland Plains, Long Beach, and Clatsop Plains for four intervals: pre-jetty - 1920s (Interval 1), 1920s - 1950s (Interval 2), 1950s - 1990s (Interval 3), and 1920s 1990s (Interval 4). This analysis is part of the Southwest Washington Coastal Erosion Study (SWCES), the goals of which are to understand and predict the morphologic behavior of the Columbia River littoral cell on a management scale of tens of kilometers and decades. We obtain topographic Light Detection and Ranging (LIDAR) data from a joint project by the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), National Aeronautic and Space Administration (NASA), and the Washington State Department of Ecology (DOE) and bathymetric data from the U.S. Coast and Geodetic Survey (USC&GS), U.S. Army Corps of Engineers (USACE), USGS, and the DOE. Shoreline data are digitized from T-Sheets and aerial photographs from the USC&GS and National Ocean Service (NOS). Instead of uncritically adjusting each survey to NAVD88, a common vertical land-based datum, we adjust some surveys to produce optimal results according to the following criteria. First, we minimize offsets in overlapping surveys within the same era, and second, we minimize bathymetric changes (relative to the 1990s) in deep water, where we assume minimal change has taken place. We grid bathymetric and topographic datasets using kriging and triangulation algorithms, calculate bathymetric-change surfaces for each interval, and calculate volume changes within polygons that are overlaid on the bathymetric-change surfaces. We find similar morphologic changes near the entrances to Grays Harbor and the Columbia River following jetty construction between 1898 and 1916 at the Grays Harbor entrance and between 1885 and

  7. Wang Jinzhen Attended the Forum on Cooperation & Development between Yangtze River Delta and Baltic Sea Region

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ On October 17,on behalf of CCPIT,Vice-Chairman Wang Jinzhen attended the opening ceremony of the 3rd Forum on Cooperation & Development between Yangtze River Delta Region of China and Baltic Sea Region of Europe,where he delivered a speech.

  8. Seasonal Variations of Stable Isotope Composition of River Flow in Permafrost Regions of Yenisei and Kolyma Rivers (Russia)

    Science.gov (United States)

    Streletskiy, D. A.; Davydova, A.; Davydov, S. P.; Opel, T.; Shiklomanov, A. I.; Shiklomanov, N. I.; Streletskaya, I. D.; Tananaev, N.; Tokarev, I.

    2015-12-01

    Permafrost plays an important role in the hydrology of the northern regions. To investigate the role of climate change on permafrost degradation and hydrology, extensive field work was conducted in a series of small watersheds located in the discontinuous permafrost zone of the lower Yenisei River near Igarka, and in the continuous permafrost zone of the Kolyma River near Cherskii. Climatic, hydrologic and permafrost characteristics were monitored at both locations over a three year period and extended using historical data. Stable isotope composition of rain, snow, water from lakes and rivers, and various types of ground ice was used to determine various inputs and runoff pathways to a river flow in several watersheds. The study found that water flow of smaller creeks follows precipitation closely, while flow of larger rivers is affected by evaporation effects related to water storage in thermokarst lakes. Ground ice of the epigenetic permafrost near Igarka has a similar isotopic composition as that of Holocene permafrost and contemporary late summer precipitation. Ground ice of the syngenetic Pleistocene permafrost (Ice Complex) near Cherskii has a significantly lighter isotopic composition than pore water of the active and transient layers. Increases in air temperature resulted in thickening of the active-layer and melting of ice that reach the transient layer in continuous permafrost. In areas where the transient layer severely reduced as a result of intense forest fires and other landscape disturbances, ground ice from permafrost is also involved in hydrological processes. Progressive decrease in the seasonal freezing layer thickness and a lower permafrost table promoted more groundwater storage and redistribution of summer precipitation towards winter baseflow in discontinuous permafrost region. The major contribution of permafrost at both locations is not through the melting of ground ice, but through changes in soil properties affecting the water flow.

  9. Regional scale groundwater modelling study for Ganga River basin

    Science.gov (United States)

    Maheswaran, R.; Khosa, R.; Gosain, A. K.; Lahari, S.; Sinha, S. K.; Chahar, B. R.; Dhanya, C. T.

    2016-10-01

    Subsurface movement of water within the alluvial formations of Ganga Basin System of North and East India, extending over an area of 1 million km2, was simulated using Visual MODFLOW based transient numerical model. The study incorporates historical groundwater developments as recorded by various concerned agencies and also accommodates the role of some of the major tributaries of River Ganga as geo-hydrological boundaries. Geo-stratigraphic structures, along with corresponding hydrological parameters,were obtained from Central Groundwater Board, India,and used in the study which was carried out over a time horizon of 4.5 years. The model parameters were fine tuned for calibration using Parameter Estimation (PEST) simulations. Analyses of the stream aquifer interaction using Zone Budget has allowed demarcation of the losing and gaining stretches along the main stem of River Ganga as well as some of its principal tributaries. From a management perspective,and entirely consistent with general understanding, it is seen that unabated long term groundwater extraction within the study basin has induced a sharp decrease in critical dry weather base flow contributions. In view of a surge in demand for dry season irrigation water for agriculture in the area, numerical models can be a useful tool to generate not only an understanding of the underlying groundwater system but also facilitate development of basin-wide detailed impact scenarios as inputs for management and policy action.

  10. Savannah River Region: Transition between the Gulf and Atlantic Coastal Plains. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Zullo, V.A.; Harris, W.B.; Price, V. [eds.

    1990-12-31

    The focus of the this conference of Coastal Plains geologists was on the Savannah River region of Georgia and South Carolina, and particularly on the geology of the US Department of Energy`s 300 square mile Savannah River Site (SRS) in western South Carolina. Current geological studies indicate that the Mesozoic-Cenozoic section in the Savannah River region is transitional between that of the Gulf Coastal Plain to the southwest and that of the Atlantic Coastal Plain to the northeast. With the transitional aspect of the region as its theme, the first session was devoted to overviews of Cretaceous and Paleogene geology in the Gulf and Atlantic Coastal Plains. Succeeding presentations and resulting discussions dealt with more specific problems in structural, lithostratigraphic, hydrological, biostratigraphic, and cyclostratigraphic analysis, and of correlation to standard stratigraphic frameworks. For these conference proceedings, individual papers have been processed separately for the Energy Data Base.

  11. A River, A Region and a Research Problem.

    Science.gov (United States)

    projecting the efficient location of water related industry via regional linear programming. The spatial general equilibrium approach allows an analysis of...advanced, with less empirical and comprehensive theoretical content. Yet the strategy of general equilibrium analysis is maintained. (Author)

  12. Facies architecture within a regional glaciolacustrine basin: Copper River, Alaska

    Science.gov (United States)

    Bennett, Matthew R.; Huddart, David; Thomas, Geoffrey S. P.

    2002-11-01

    This paper defines the principal architectural elements present within the Pleistocene, glaciolacustrine basin-fill of the Copper River Basin in Alaska. The Copper River drains an intermontane basin via a single deeply incised trench through the Chugach Mountains to the Gulf of Alaska. This trench was blocked by ice during the last glacial cycle and a large ice-dammed lake, referred to as Lake Atna, filled much of the Copper Basin. Facies analysis within the basin floor allows a series of associations to be defined consistent with the basinward transport of sediment deposited along calving ice margins and at the basin edge. Basinward transport involves a continuum of gravity driven processes, including slumping, cohesive debris flow, hyperconcentrated/concentrated density flows, and turbidity currents. This basinward transport results in the deposition of a series of subaqueous fans, of which two main types are recognised. (1) Large, stratified, basin floor fans, which extend over at least 5 km and are exposed in the basin centre. These fans are composed of multiple lobes, incised by large mega-channels, giving fan architectures that are dominated by horizontal strata and large, cross-cutting channel-fills. Individual lobes and channel-fills consist of combinations of: diamict derived from iceberg rainout and the ice-marginal release of subglacial sediment; multiple units of fining upward gravels which grade vertically into parallel laminated and rippled fine sands and silts, deposited by a range of density flows and currents derived from the subaqueous discharge of meltwater; and rhythmites grading vertically into diamicts deposited from a range of sediment-density flows re-mobilising sediment deposited by either iceberg rainout or the ice-marginal release of sediment. (2) Small, complex, proximal fans, which extend over less than 2 km, and are exposed in the southern part of the basin. These fans are composed of coalescing and prograding lobes of diamict and

  13. Macroinvertebrate distribution and aquatic ecology in the Ruoergai (Zoige) Wetland, the Yellow River source region

    Science.gov (United States)

    Zhao, Na; Xu, Mengzhen; Li, Zhiwei; Wang, Zhaoyin; Zhou, Hanmi

    2017-09-01

    The Ruoergai (Zoige) Wetland, the largest plateau peatland in the world, is located in the Yellow River source region. The discharge of the Yellow River increases greatly after flowing through the Ruoergai Wetland. The aquatic ecosystem of the Ruoergai Wetland is crucial to the whole Yellow River basin. The Ruoergai wetland has three main kinds of water bodies: rivers, oxbow lakes, and marsh wetlands. In this study, macroinvertebrates were used as indicators to assess the aquatic ecological status because their assemblage structures indicate long-term changes in environments with high sensitivity. Field investigations were conducted in July, 2012 and in July, 2013. A total of 72 taxa of macroinvertebrates belonging to 35 families and 67 genera were sampled and identified. Insecta was the dominant group in the Ruoergai Basin. The alpha diversity of macroinvertebrates at any single sampling site was low, while the alpha diversity on a basin-wide scale was much higher. Macroinvertebrate assemblages in rivers, oxbow lakes, and marsh wetlands differ markedly. Hydrological connectivity was a primary factor causing the variance of the bio-community. The river channels had the highest alpha diversity of macroinvertebrates, followed by marsh wetlands and oxbow lakes. The density and biomass of Gastropoda, collector filterers, and scrapers increased from rivers to oxbow lakes and then to marsh wetlands. The river ecology was particular in the Ruoergai Wetland with the high beta diversity of macroinvertebrates, the low alpha diversity of macroinvertebrates, and the low taxa richness, density, and biomass of EPT (Ephemeroptera, Plecoptera, Trichoptera). To maintain high alpha diversity of macroinvertebrates macroinvertebrates in the Ruoergai Wetland, moderate connectivity of oxbow lakes and marsh wetlands with rivers and measures to control headwater erosion are both crucial.

  14. Macroinvertebrate distribution and aquatic ecology in the Ruoergai (Zoige) Wetland, the Yellow River source region

    Science.gov (United States)

    Zhao, Na; Xu, Mengzhen; Li, Zhiwei; Wang, Zhaoyin; Zhou, Hanmi

    2016-12-01

    The Ruoergai (Zoige) Wetland, the largest plateau peatland in the world, is located in the Yellow River source region. The discharge of the Yellow River increases greatly after flowing through the Ruoergai Wetland. The aquatic ecosystem of the Ruoergai Wetland is crucial to the whole Yellow River basin. The Ruoergai wetland has three main kinds of water bodies: rivers, oxbow lakes, and marsh wetlands. In this study, macroinvertebrates were used as indicators to assess the aquatic ecological status because their assemblage structures indicate long-term changes in environments with high sensitivity. Field investigations were conducted in July, 2012 and in July, 2013. A total of 72 taxa of macroinvertebrates belonging to 35 families and 67 genera were sampled and identified. Insecta was the dominant group in the Ruoergai Basin. The alpha diversity of macroinvertebrates at any single sampling site was low, while the alpha diversity on a basin-wide scale was much higher. Macroinvertebrate assemblages in rivers, oxbow lakes, and marsh wetlands differ markedly. Hydrological connectivity was a primary factor causing the variance of the bio-community. The river channels had the highest alpha diversity of macroinvertebrates, followed by marsh wetlands and oxbow lakes. The density and biomass of Gastropoda, collector filterers, and scrapers increased from rivers to oxbow lakes and then to marsh wetlands. The river ecology was particular in the Ruoergai Wetland with the high beta diversity of macroinvertebrates, the low alpha diversity of macroinvertebrates, and the low taxa richness, density, and biomass of EPT (Ephemeroptera, Plecoptera, Trichoptera). To maintain high alpha diversity of macroinvertebrates macroinvertebrates in the Ruoergai Wetland, moderate connectivity of oxbow lakes and marsh wetlands with rivers and measures to control headwater erosion are both crucial.

  15. Linking ecology to hydrology and geomorphology using river reach classification for the Greater Mekong Region

    Science.gov (United States)

    Ouelette Dallaire, Camille; Lehner, Bernhard

    2016-04-01

    Large-scale development projects, such as hydropower dams, in the Greater Mekong Region (GMR) are putting high pressure on freshwater resources. Environmental impact assessments are needed in the region to understand the possible impacts of these projects. These assessments often require biodiversity data that can be costly to acquire both in terms of time and money. It is often assumed that river or ecosystem classes, based on geo-physical characteristics, can be used as biodiversity proxies in large scale assessments to account for a lack of biodiversity data. However, there has been little research to compare the spatial distribution of river classes and fish species. It is unclear how well river classes are able to represent the distribution of fish and, more generally, biodiversity. To address this question, a set of two classifications were compared to a newly available dataset of fish species distribution in the GMR (Allen et al., 2012). The classifications were derived from two different methods to test which could potentially better represent fish assemblages. The first classification is derived using regional expert knowledge and the second using K-mean analysis. Both are using the same geophysical datasets. The two datasets were used in a Redundancy Analysis (RDA) to calculate which proportion of the variability in the fish species data can be explained by the river classes. The RDA resulted in R2 of 0.44 for the supervised classification and 0.41for the statistical classification, showing a moderate correlation between the datasets. Based on these results, using river classes as biodiversity proxy is deemed reasonable. However, some of the variability in the distribution of fish species cannot be related simply to geophysical factors. River classes may capture different elements such as unique habitats and associated, possibly unknown, endemic species that indices based only on biological data do not. Hence, river classes can be a good alternative and

  16. Nydiagnosticeret kongenit transposition hos en 76-årig kvinde

    DEFF Research Database (Denmark)

    Sloth, Astrid Drivsholm; Jensen, Jesper Khedri; Hald Steffensen, Flemming

    2009-01-01

    A case of congenitally corrected transposition presenting for the first time with second-degree AV block in a 76-year-old woman is presented. This case demonstrates that congenitally corrected transposition can remain asymptomatic and undiagnosed, especially when no other cardiac defects are pres...

  17. Transposition with atypical coronary pattern: the Aubert technique.

    Science.gov (United States)

    Pita-Fernández, Ana; González-López, María T; Gil-Jaurena, Juan M

    2017-03-06

    The arterial switch operation is currently the gold standard technique for repair of transposition of the great arteries. Some atypical coronary patterns such as intramural, interarterial, and a unique posterior button are associated with more complexity and surgical risk. We report a successful Aubert operation for transposition of the great arteries associated with a single and interarterial coronary artery arising from a posterior sinus.

  18. Transposition pattern of a modified Ds element in tomato

    NARCIS (Netherlands)

    Rommens, Caius M.T.; Munyikwa, Tichafa R.I.; Overduin, Bert; Nijkamp, H. John J.; Hille, Jacques

    1993-01-01

    Several aspects of transposition of an in vitro modified Ds element are described. This Ds element, designated Ds-r, is equipped with bacterial plasmid sequences and can, therefore, be rescued from the plant genome. Our results indicate that the Ds-r element has a 'late' timing of transposition from

  19. Nydiagnosticeret kongenit transposition hos en 76-årig kvinde

    DEFF Research Database (Denmark)

    Sloth, Astrid Drivsholm; Jensen, Jesper Khedri; Steffensen, Flemming Hald

    2009-01-01

    A case of congenitally corrected transposition presenting for the first time with second-degree AV block in a 76-year-old woman is presented. This case demonstrates that congenitally corrected transposition can remain asymptomatic and undiagnosed, especially when no other cardiac defects are pres...

  20. Improving the accuracy of flood forecasting with transpositions of ensemble NWP rainfall fields considering orographic effects

    Science.gov (United States)

    Yu, Wansik; Nakakita, Eiichi; Kim, Sunmin; Yamaguchi, Kosei

    2016-08-01

    The use of meteorological ensembles to produce sets of hydrological predictions increased the capability to issue flood warnings. However, space scale of the hydrological domain is still much finer than meteorological model, and NWP models have challenges with displacement. The main objective of this study to enhance the transposition method proposed in Yu et al. (2014) and to suggest the post-processing ensemble flood forecasting method for the real-time updating and the accuracy improvement of flood forecasts that considers the separation of the orographic rainfall and the correction of misplaced rain distributions using additional ensemble information through the transposition of rain distributions. In the first step of the proposed method, ensemble forecast rainfalls from a numerical weather prediction (NWP) model are separated into orographic and non-orographic rainfall fields using atmospheric variables and the extraction of topographic effect. Then the non-orographic rainfall fields are examined by the transposition scheme to produce additional ensemble information and new ensemble NWP rainfall fields are calculated by recombining the transposition results of non-orographic rain fields with separated orographic rainfall fields for a generation of place-corrected ensemble information. Then, the additional ensemble information is applied into a hydrologic model for post-flood forecasting with a 6-h interval. The newly proposed method has a clear advantage to improve the accuracy of mean value of ensemble flood forecasting. Our study is carried out and verified using the largest flood event by typhoon 'Talas' of 2011 over the two catchments, which are Futatsuno (356.1 km2) and Nanairo (182.1 km2) dam catchments of Shingu river basin (2360 km2), which is located in the Kii peninsula, Japan.

  1. Sources of excess urban carbonaceous aerosol in the Pearl River delta region, China

    Science.gov (United States)

    Carbonaceous aerosol is one of the important constituents of fine particulate matter (PM2.5) in Southern China, including the Pearl River Delta (PRD) region and Hong Kong (HK). During the study period (October and December of 2002, and March and June of 2003), the monthly average...

  2. Regional Effects of Agricultural Conservation Practices on Nutrient Transport in the Upper Mississippi River Basin.

    Science.gov (United States)

    García, Ana María; Alexander, Richard B; Arnold, Jeffrey G; Norfleet, Lee; White, Michael J; Robertson, Dale M; Schwarz, Gregory

    2016-07-01

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  3. Regional effects of agricultural conservation practices on nutrient transport in the Upper Mississippi River Basin

    Science.gov (United States)

    Garcia, Ana Maria.; Alexander, Richard B.; Arnold, Jeffrey G.; Norfleet, Lee; White, Michael J.; Robertson, Dale; Schwarz, Gregory

    2016-01-01

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  4. The Studies of Regional Water Circulation Patterns in the Yerqiang River Basin

    Institute of Scientific and Technical Information of China (English)

    REN Jiaguo; WU Qianqian; ZHENG Xilai; XU Mo

    2006-01-01

    Based on the characteristic of ‘one river one oasis' in the arid areas, the Yerqiang River Basin, which is the largest irrigated area of Xinjiang, is taken as an example in this paper, and the regional water circulation pattern is investigated through the analysis of 60 groups of isotope data in the basin. From the phreatic evaporation data analysis of different soils, we study the law of phreatic evaporation, complete the research of the main consumption path of the groundwater,and improve the assessment precision of water resources. The transformation mount of regional water resources are predicted by calculation, which provides a scientific basis for water resources assessment and allocation in arid regions, and offers a new method for the study of regional water circulation patterns.

  5. Dissolved nitrogen in rivers: comparing pristine and impacted regions of Brazil

    Directory of Open Access Journals (Sweden)

    LA Martinelli

    Full Text Available Riverine nitrogen distribution is increasingly controlled by anthropogenic activities in their watersheds, regardless of spatial scale, climate, and geographical zone. Consequently, modelling efforts to predict the export of nitrogen from rivers worldwide have used attributes such as population density, land use, urbanization and sanitation. These models have greatly enhanced our understanding of the sources and fate of nitrogen added to terrestrial systems and transported to rivers and streams, especially for developed countries of the North temperate zone. However, much of the world's population lives in developing countries of the tropics, where the effects of human activities on riverine N exports are still poorly understood. In an effort to close this gap, we compare riverine nitrogen data from 32 Brazilian rivers draining two contrasting regions in this tropical country in terms of economic development - the State of São Paulo and the Amazon. Our data include nitrogen in different dissolved forms, such as Dissolved Inorganic Nitrogen (DIN and Dissolved Organic Nitrogen (DON. The results show that nitrogen concentrations decreased as river runoff increased in both study areas, and that concentrations were significantly higher in rivers draining the most economically developed region. The relationships between nitrogen concentrations and fluxes with demographic parameters such as population density were also determined and compared to those in temperate systems. In contrast to temperate watersheds, we found that nitrogen fluxes increased only after population densities were higher than 10 individuals per km².

  6. Transboundary study of the Milk River aquifer (Canada, USA): geological, conceptual and numerical models for the sound management of the regional groundwater resources

    Science.gov (United States)

    Pétré, Marie-Amélie; Rivera, Alfonso; Lefebvre, René

    2016-04-01

    The Milk River transboundary aquifer straddles southern Alberta (Canada) and northern Montana (United States), a semi-arid and water-short region. The extensive use of this regional sandstone aquifer over the 20th century has led to a major drop in water levels locally, and concerns about the durability of the resources have been raised since the mid-1950. Even though the Milk River Aquifer (MRA) has been studied for decades, most of the previous studies were limited by the international border, preventing a sound understanding of the aquifer dynamics. Yet, a complete portrait of the aquifer is required for proper management of this shared resource. The transboundary study of the MRA aims to overcome transboundary limitations by providing a comprehensive characterization of the groundwater resource at the aquifer scale, following a three-stage approach: 1) The development of a 3D unified geological model of the MRA (50,000 km2). The stratigraphic framework on both sides of the border was harmonized and various sources of geological data were unified to build the transboundary geological model. The delineation of the aquifer and the geometry and thicknesses of the geological units were defined continuously across the border. 2) Elaboration of a conceptual hydrogeological model by linking hydrogeological and geochemical data with the 3D unified geological model. This stage is based on a thorough literature review and focused complementary field work on both sides of the border. The conceptual model includes the determination of the groundwater flow pattern, the spatial distribution of hydraulic properties, a groundwater budget and the definition of the groundwater types. Isotopes (3H, 14C, 36Cl) were used to delineate the recharge area as well as the active and low-flow areas. 3) The building of a 3D numerical groundwater flow model of the MRA (26,000 km2). This model is a transposition of the geological and hydrogeological conceptual models. A pre

  7. Climate change and its impacts on river discharge in two climate regions in China

    Science.gov (United States)

    Xu, H.; Luo, Y.

    2015-11-01

    Understanding the heterogeneity of climate change and its impacts on annual and seasonal discharge and the difference between median flow and extreme flow in different climate regions is of utmost importance to successful water management. To quantify the spatial and temporal heterogeneity of climate change impacts on hydrological processes, this study simulated river discharge in the River Huangfuchuan in semi-arid northern China and in the River Xiangxi in humid southern China. The study assessed the uncertainty in projected discharge for three time periods (2020s, 2050s and 2080s) using seven equally weighted GCMs (global climate models) for the SRES (Special Reports on Emissions Scenarios) A1B scenario. Climate projections that were applied to semi-distributed hydrological models (Soil Water Assessment Tools, SWAT) in both catchments showed trends toward warmer and wetter conditions, particularly for the River Huangfuchuan. Results based on seven GCMs' projections indicated changes from -1.1 to 8.6 °C and 0.3 to 7.0 °C in seasonal temperature and changes from -29 to 139 % and -32 to 85 % in seasonal precipitation in the rivers Huangfuchuan and Xiangxi, respectively. The largest increases in temperature and precipitation in both catchments were projected in the spring and winter seasons. The main projected hydrologic impact was a more pronounced increase in annual discharge in the River Huangfuchuan than in the River Xiangxi. Most of the GCMs projected increased discharge in all seasons, especially in spring, although the magnitude of these increases varied between GCMs. The peak flows were projected to appear earlier than usual in the River Huangfuchuan and later than usual in the River Xiangxi, while the GCMs were fairly consistent in projecting increased extreme flows in both catchments with varying magnitude compared to median flows. For the River Huangfuchuan in the 2080s, median flow changed from -2 to 304 %, compared to a -1 to 145 % change in high flow

  8. An Analysis of Labor Resources "One River and Two Tributaries" Region in Tibet, China

    Institute of Scientific and Technical Information of China (English)

    PENG Chuan-zhong; LI Xiang-mei; LIU Jian; ZHONG Xiang-hao

    2005-01-01

    Focusing on the region of Yarlung Zangbo River and the middle reaches of its two tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the "One River and Two Tributaries" region), and based on the data from China 3rd, 4th and 5th population censuses, the article has analyzed change patterns of this region's labor force. Major findings from the study are summarized as follows: ① Compared with the data from the 3rd census, labor force population in 2000 has increased significantly. ② Children dependency coefficient has dropped, while old people dependency coefficient has changed very slightly with an increase of 0.047% only. ③ Compared 2000 with 1982, illiteracy and semi-illiteracy rate of the population above 15 years old have decreased significantly by 30.69 percentage points, but still higher than the national average. ④ Women's illiteracy rate has dropped faster than men's, but up to 2000 it was generally quite high. The upgrading of the entire population's overall quality has a long way to go.

  9. Valuing nature-based recreation in public natural areas of the Apalachicola River region, Florida.

    Science.gov (United States)

    Shrestha, Ram K; Stein, Taylor V; Clark, Julie

    2007-12-01

    As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves-highlighting the importance of this new and growing phenomenon. We analyze visitors' demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay 74.18 dollars per visit-day for nature-based recreation resulting in a total economic value of 484.56 million dollars attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida's unique ecosystems.

  10. Regional Flood Frequency Analysis in the Volta River Basin, West Africa

    Directory of Open Access Journals (Sweden)

    Kossi Komi

    2016-02-01

    Full Text Available In the Volta River Basin, flooding has been one of the most damaging natural hazards during the last few decades. Therefore, flood frequency estimates are important for disaster risk management. This study aims at improving knowledge of flood frequencies in the Volta River Basin using regional frequency analysis based on L-moments. Hence, three homogeneous groups have been identified based on cluster analysis and a homogeneity test. By using L-moment diagrams and goodness of fit tests, the generalized extreme value and the generalized Pareto distributions are found suitable to yield accurate flood quantiles in the Volta River Basin. Finally, regression models of the mean annual flood with the size of the drainage area, mean basin slope and mean annual rainfall are proposed to enable flood frequency estimation of ungauged sites within the study area.

  11. Exposure of implants using a modified multiple-flap transposition vestibuloplasty.

    Science.gov (United States)

    Hakim, S G; Driemel, O; Jacobsen, H C; Hermes, D; Sieg, P

    2006-12-01

    To introduce a minimally invasive operation to improve the condition of the soft tissues around the implants in an atrophied mandible, at the same time, as uncovering the implants. A multiple-flap transposition vestibuloplasty was done in 11 patients after the insertion of four implants in the interforaminal region of an atrophied mandible. Improvement in soft tissues and successful exposure of implants and attached gingiva were evaluated during a follow-up period of 55 months. All the patients were operated on local anaesthesia as outpatients. Adequate exposure of implants and an area of attached gingiva 4-9 mm wide were attained. There was no bleeding on probing or local infection. The transposition multiple-flap vestibuloplasty is a simple and minimally invasive method of improving the condition of soft tissue after insertion of implants. It does not limit the patients' routine activities and avoids staged operations.

  12. Keeler's theorem and products of distinct transpositions

    CERN Document Server

    Evans, Ron; Nguyen, Tuan

    2012-01-01

    An episode of Futurama features a two-body mind-switching machine which will not work more than once on the same pair of bodies. After the Futurama community indulges in a mind-switching spree, the question is asked, "Can the switching be undone so as to restore all minds to their original bodies?" Ken Keeler found an algorithm that undoes any mind-scrambling permutation with the aid of two "outsiders". We refine Keeler's result by providing a more efficient algorithm that uses the smallest possible number of switches. We also present best possible algorithms for undoing two natural sequences of switches, each sequence effecting a cyclic mind-scrambling permutation in the symmetric group S_n. Finally, we give necessary and sufficient conditions on m and n for the identity permutation to be expressible as a product of m distinct transpositions in S_n.

  13. Using regional flow classes as references to analyse flow regime anomalies across a set of regulated Canadian rivers

    Science.gov (United States)

    McLaughlin, Fraser; Lapointe, Michel; Bourque, Guillaume; Boisclair, Daniel

    2014-11-01

    It is well established that a river's natural flow regime is a key determinant of ecological integrity and that dam regulated-flow releases can be detrimental to biotic communities and even affect river ecosystem structure (e.g. Poff and Zimmerman, 2010). Regional flow classes, groups of rivers that share similar natural flow regimes (called ‘river types' by Poff and Zimmerman (2010)) and to which regional fish communities are ‘adapted', have been proposed as units of analysis to identify significant damming related flow alteration (e.g. Poff, 1996; Poff and Zimmerman, 2010; McManamay et al., 2012a). Specifically, the natural range of flow behaviour within regional classes can be used to identify clearly anomalous flow features in rivers regulated by dams. Through ordination analysis on 70 ecologically important flow indices, we isolated five distinctive regional groupings of natural flow regimes among the 96 unregulated rivers located in study regions of South Eastern and South Western Canada, selected based on watershed characteristics as possible references for the 13 hydro-regulated, NSERC-HydroNet study rivers in British Columbia, Alberta, Ontario, Quebec and New Brunswick. The distinguishing characteristics of natural flow regimes within each flow class are explored through visualization in principal component space. The 16 regulated HydroNet sites were assigned to appropriate regional flow classes through discriminant function analysis based on shared geographic location and watershed characteristics. Anomalous flow features in the regulated rivers are then characterized by type and strength, based on identification of flow indices that are significantly different from observed natural variability in the relevant regional class. The magnitude distributions and the main axes of variability in index anomalies are analysed, across regions and regulation types (storage, peaking and run-of-the-river (RoR)). We also discuss the potential biological

  14. Observations of the frontal region of a buoyant river plume using an autonomous underwater vehicle

    Science.gov (United States)

    Rogowski, Peter; Terrill, Eric; Chen, Jialin

    2014-11-01

    To characterize the transitional region from the near-field to far-field of a river plume entering coastal waters, we conducted four surveys using an autonomous underwater vehicle (AUV) to target the outflow of the New River Inlet, North Carolina, during maximum ebb tide. The utilization of a mobile sensor to synoptically observe current velocity data in tandem with natural river plume tracers (e.g., colored dissolved organic matter, salinity) was essential in understanding the mechanisms driving the observed circulation and mixing patterns within these waters. We find that this region is regularly impacted by two primary processes: (1) the interaction of an old dredged channel plume with the main discharge and (2) the recirculation of the discharge plume by an eddy that persistently forms between the old channel and main discharge location. Wind-driven processes in the nearshore can enhance the interaction of these two plumes resulting in unstable regions where mixing of the merged plume with the receiving waters is accelerated. We also conduct comparisons between AUV velocity observations from two surveys and their corresponding velocity outputs from a parallelized quasi-3-D model. We conclude that the ability to observe the estuarine outflow transitional region at near-synoptic temporal scales and resolutions discussed in this paper is key in providing the mechanisms driving local circulation which is essential for proper parameterization of high-resolution numerical coastal models.

  15. Patterns and structures of land use change in the Three Rivers Headwaters Region of China.

    Science.gov (United States)

    Yang, Jingbiao; Wang, Yi Chen; Guo, Luo; Xue, Dayuan

    2015-01-01

    Located in Qinghai Province of China, the Three Rivers Headwaters Region is the source region of the Yangtze, Yellow and Lantsang Rivers, and plays an important role in biodiversity conservation and regulating water supply. Despite many efforts on land use change in Qinghai, knowledge of the spatial variation of land use change is still lacking. This study examines the patterns of land use change across various watersheds, prefectures and the temple surroundings. Remote sensing images of 1987, 1997 and 2007 were analyzed to derive land use distributions; patterns and structures of the landscape were then quantified with landscape metrics. The results illustrated that the Yangtze River headwater region had more diverse and more evenly distributed landscape, while the Lantsang and the Yellow headwater regions showed a decline in landscape diversity. Comparison of the land use patterns of four prefectures revealed that Yushu Prefecture experienced an increase in landscape diversity from 1987 to 2007 while the land use patches in Guoluo Prefecture exhibited more aggregated patterns than other prefectures. Analysis of the spatial variations of land use change in the temple surroundings illustrated that 19.7% and 35.9% of the temples in Guoluo and Yushu Prefectures, respectively, encountered land use change for their immediate areas within 2 km. Comparison of the surroundings of temples and human settlements found that land use change was not evenly distributed, and that greater land use change had occurred for the surroundings of human settlements. Such findings provided insights into the spatial variation of land use change in the Three Rivers Headwaters Region.

  16. Identifying hotspots and management of critical ecosystem services in rapidly urbanizing Yangtze River Delta Region, China.

    Science.gov (United States)

    Cai, Wenbo; Gibbs, David; Zhang, Lang; Ferrier, Graham; Cai, Yongli

    2017-04-15

    Rapid urbanization has altered many ecosystems, causing a decline in many ecosystem services, generating serious ecological crisis. To cope with these challenges, we presented a comprehensive framework comprising five core steps for identifying and managing hotspots of critical ecosystem services in a rapid urbanizing region. This framework was applied in the case study of the Yangtze River Delta (YRD) Region. The study showed that there was large spatial heterogeneity in the hotspots of ecosystem services in the region, hotspots of supporting services and regulating services aggregately distributing in the southwest mountainous areas while hotspots of provisioning services mainly in the northeast plain, and hotspots of cultural services widespread in the waterbodies and southwest mountainous areas. The regionalization of the critical ecosystem services was made through the hotspot analysis. This study provided valuable information for environmental planning and management in a rapid urbanizing region and helped improve China's ecological redlines policy at regional scale. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Repetitive transpositions of mitochondrial DNA sequences to the nucleus during the radiation of horseshoe bats (Rhinolophus, Chiroptera).

    Science.gov (United States)

    Shi, Huizhen; Dong, Ji; Irwin, David M; Zhang, Shuyi; Mao, Xiuguang

    2016-05-01

    Transposition of mitochondrial DNA into the nucleus, which gives rise to nuclear mitochondrial DNAs (NUMTs), has been well documented in eukaryotes. However, very few studies have assessed the frequency of these transpositions during the evolutionary history of a specific taxonomic group. Here we used the horseshoe bats (Rhinolophus) as a case study to determine the frequency and relative timing of nuclear transfers of mitochondrial control region sequences. For this, phylogenetic and coalescent analyzes were performed on NUMTs and authentic mtDNA sequences generated from eight horseshoe bat species. Our results suggest at least three independent transpositions, including two ancient and one more recent, during the evolutionary history of Rhinolophus. The two ancient transpositions are represented by the NUMT-1 and -2 clades, with each clade consisting of NUMTs from almost all studied species but originating from different portions of the mtDNA genome. Furthermore, estimates of the most recent common ancestor for each clade corresponded to the time of the initial diversification of this genus. The recent transposition is represented by NUMT-3, which was discovered only in a specific subgroup of Rhinolophus and exhibited a close relationship to its mitochondrial counterpart. Our similarity searches of mtDNA in the R. ferrumequinum genome confirmed the presence of NUMT-1 and NUMT-2 clade sequences and, for the first time, assessed the extent of NUMTs in a bat genome. To our knowledge, this is the first study to report on the frequency of transpositions of mtDNA occurring before the common ancestry of a genus.

  18. Effects of stream flow intermittency on riparian vegetation of a semiarid region river (San Pedro River, Arizona)

    Science.gov (United States)

    Stromberg, J.C.; Bagstad, K.J.; Leenhouts, J.M.; Lite, S.J.; Makings, E.

    2005-01-01

    The San Pedro River in the southwestern United States retains a natural flood regime and has several reaches with perennial stream flow and shallow ground water. However, much of the river flows intermittently. Urbanization-linked declines in regional ground-water levels have raised concerns over the future status of the riverine ecosystem in some parts of the river, while restoration-linked decreases in agricultural ground-water pumping are expected to increase stream flows in other parts. This study describes the response of the streamside herbaceous vegetation to changes in stream flow permanence. During the early summer dry season, streamside herbaceous cover and species richness declined continuously across spatial gradients of flow permanence, and composition shifted from hydric to mesic species at sites with more intermittent flow. Hydrologic threshold values were evident for one plant functional group: Schoenoplectus acutus, Juncus torreyi, and other hydric riparian plants declined sharply in cover with loss of perennial stream flow. In contrast, cover of mesic riparian perennials (including Cynodon dactylon, an introduced species) increased at sites with intermittent flow. Patterns of hydric and mesic riparian annuals varied by season: in the early summer dry season their cover declined continuously as flow became more intermittent, while in the late summer wet season their cover increased as the flow became more intermittent. Periodic drought at the intermittent sites may increase opportunities for establishment of these annuals during the monsoonal flood season. During the late summer flood season, stream flow was present at most sites, and fewer vegetation traits were correlated with flow permanence; cover and richness were correlated with other environmental factors including site elevation and substrate nitrate level and particle size. Although perennial-flow and intermittent-flow sites support different streamside plant communities, all of the plant

  19. Run-of-river power plants in Alpine regions: whither optimal capacity?

    Science.gov (United States)

    Lazzaro, Gianluca; Botter, Gianluca

    2015-04-01

    Hydropower is the major renewable electricity generation technology worldwide. The future expansion of this technology mostly relies on the development of small run-of-river projects, in which a fraction of the running flows is diverted from the river to a turbine for energy production. Even though small hydro inflicts a smaller impact on aquatic ecosystems and local communities compared to large dams, it cannot prevent stresses on plant, animal, and human well-being. This is especially true in mountain regions where the plant outflow is located several kilometers downstream of the intake, thereby inducing the depletion of river reaches of considerable length. Moreover, the negative cumulative effects of run-of-river systems operating along the same river threaten the ability of stream networks to supply ecological corridors for plants, invertebrates or fishes, and support biodiversity. Research in this area is severely lacking. Therefore, the prediction of the long-term impacts associated to the expansion of run-of-river projects induced by global-scale incentive policies remains highly uncertain. This contribution aims at providing objective tools to address the preliminary choice of the capacity of a run-of-river hydropower plant when the economic value of the plant and the alteration of the flow regime are simultaneously accounted for. This is done using the concepts of Pareto-optimality and Pareto-dominance, which are powerful tools suited to face multi-objective optimization in presence of conflicting goals, such as the maximization of the profitability and the minimization of the hydrologic disturbance induced by the plant in the river reach between the intake and the outflow. The application to a set of case studies belonging to the Piave River basin (Italy) suggests that optimal solutions are strongly dependent the natural flow regime at the plant intake. While in some cases (namely, reduced streamflow variability) the optimal trade-off between economic

  20. Hydrology and digital simulation of the regional aquifer system, eastern Snake River Plain, Idaho

    Science.gov (United States)

    Garabedian, S.P.

    1992-01-01

    The occurrence and movement of water in the regional aquifer system that underlies the eastern Snake River Plain, Idaho, de- pend on the transmissivity and storage capacity of rocks that compose the geologic framework and on the distribution and amount of recharge and discharge of water within that frame- work. On a regional scale, most water moves horizontally through interflow zones in Quaternary basalt of the Snake River Group. In recharge and discharge areas, water also moves vertically along joints and interfingering edges of basalt flows. Aquifer thickness is largely unknown, but geophysical studies suggest that locally the Quaternary basalt may exceed several thousand feet. Along the margins of the plain, sand and gravel several hundred feet thick transmit large volumes of water.

  1. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis.

    Science.gov (United States)

    Del Senno, L; Pirastu, M; Barbieri, R; Bernardi, F; Buzzoni, D; Marchetti, G; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F

    1985-01-01

    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in a beta(+), homozygote and in a beta (+), beta(0) 39 (nonsense mutation at codon 39) double heterozygote is approximately 20% and 10% respectively of total non-alpha globin synthesis. Despite some overlapping of the results, similar beta globin synthesis levels have been obtained in 43 beta(+)-thalassaemia patients. This suggests that in the Po river delta region the most common thalassaemic genes are beta(0) 39 and beta(+) IVS I. Images PMID:2580095

  2. Run-of-river power plants in Alpine regions: Whither optimal capacity?

    Science.gov (United States)

    Lazzaro, G.; Botter, G.

    2015-07-01

    Although run-of-river hydropower represents a key source of renewable energy, it cannot prevent stresses on river ecosystems and human well-being. This is especially true in Alpine regions, where the outflow of a plant is placed several kilometers downstream of the intake, inducing the depletion of river reaches of considerable length. Here multiobjective optimization is used in the design of the capacity of run-of-river plants to identify optimal trade-offs between two contrasting objectives: the maximization of the profitability and the minimization of the hydrologic disturbance between the intake and the outflow. The latter is evaluated considering different flow metrics: mean discharge, temporal autocorrelation, and streamflow variability. Efficient and Pareto-optimal plant sizes are devised for two representative case studies belonging to the Piave river (Italy). Our results show that the optimal design capacity is strongly affected by the flow regime at the plant intake. In persistent regimes with a reduced flow variability, the optimal trade-off between economic exploitation and hydrologic disturbance is obtained for a narrow range of capacities sensibly smaller than the economic optimum. In erratic regimes featured by an enhanced flow variability, instead, the Pareto front is discontinuous and multiple trade-offs can be identified, which imply either smaller or larger plants compared to the economic optimum. In particular, large capacities reduce the impact of the plant on the streamflow variability at seasonal and interannual time scale. Multiobjective analysis could provide a clue for the development of policy actions based on the evaluation of the environmental footprint of run-of-river plants.

  3. Environmental surveillance monitoring in the Alligator Rivers Region. Report No. 34

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This report outlines the activities of the Northern Territory Supervising Authorities (NTSAs) in meeting their responsibilities for environmental management and surveillance of environmental monitoring relating to uranium mining in the Alligator Rivers Region for the six-month period to 30 September 1997. Detailed results of assessments, inspections and check monitoring for Nabarlek and Ranger deposits are presented. The current status of Jabiluka and Koongarra projects is briefly outlined. 14 figs., 2 tabs.

  4. Emergy Synthesis and Regional Sustainability Assessment: Case Study of Pan-Pearl River Delta in China

    OpenAIRE

    2014-01-01

    In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS) tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD) region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy d...

  5. Copper level and distribution in soils of forest ecosystems of Samara river region

    Directory of Open Access Journals (Sweden)

    A. A. Dubina

    2009-03-01

    Full Text Available The level and regularities of distribution of the copper in the soils of steppe and forest ecosystems of Samara river region were determined. The data on general and mobile forms of copper combination in soils of the studied ecosystems are presented. The interval of copper variation in the soils is indicated. The distribution of copper in soil genetic horizons is shown. The distinction in the copper content in soils of different types of the landscape was revealed.

  6. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis.

    OpenAIRE

    del Senno, L; Pirastu, M; Barbieri, R.; De Bernardi, F.; Buzzoni, D; Marchetti, G.; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F

    1985-01-01

    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in...

  7. Regional climate change of the greater Zambezi River Basin: a hybrid assessment

    OpenAIRE

    Schlosser, C. Adam; Strzepek, Kenneth

    2013-01-01

    Projections of regional changes in surface-air temperature and precipitation, in response to unconstrained emissions as well as a climate mitigation policy, for the Zambezi River Basin (ZRB) are presented. These projections are cast in a probabilistic context through a hybrid technique that combines the projections of the MIT Integrated Global System Model (IGSM) to pattern-change kernels from climate-model results of the Coupled Model Intercomparison Project (CMIP). Distributional changes of...

  8. The power of norms in the transposition of EU directives

    Directory of Open Access Journals (Sweden)

    Dimitrova

    2005-11-01

    Full Text Available Transposition research provides an excellent opportunity to bring new data to bear on two of the most dominant theoretical approaches to European Union studies: rational choice institutionalism and sociological institutionalism. Yet the goal of comparable testing is hampered by the underspecified nature of the sociological perspective. This paper takes some steps towards identifying and operationalising a sociological explanation of the transposition of EU directives. Examining an array of alternatives, we single out an approach that focuses on the transmission of norms as a way to explain transposition delay and content changes, and on persuasion to help explain norm change over time. To probe the validity of our explanation, we apply it to a case study of the transposition of two anti-discrimination directives from 2000 in Slovakia. In short, our paper aims to move forward the search for a testable sociological framework in EU studies, while offering an operational approach to studying the process of transposing EU directives.

  9. Shorelines of the Central Beaufort Sea, Alaska coastal region (Hulahula River to the Colville River) used in shoreline change analysis

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset includes shorelines from 63 years ranging from 1947 to 2010 for the north coast of Alaska between the Hulahula River and the Colville River. Shorelines...

  10. Universal platform for quantitative analysis of DNA transposition

    Directory of Open Access Journals (Sweden)

    Pajunen Maria I

    2010-11-01

    Full Text Available Abstract Background Completed genome projects have revealed an astonishing diversity of transposable genetic elements, implying the existence of novel element families yet to be discovered from diverse life forms. Concurrently, several better understood transposon systems have been exploited as efficient tools in molecular biology and genomics applications. Characterization of new mobile elements and improvement of the existing transposition technology platforms warrant easy-to-use assays for the quantitative analysis of DNA transposition. Results Here we developed a universal in vivo platform for the analysis of transposition frequency with class II mobile elements, i.e., DNA transposons. For each particular transposon system, cloning of the transposon ends and the cognate transposase gene, in three consecutive steps, generates a multifunctional plasmid, which drives inducible expression of the transposase gene and includes a mobilisable lacZ-containing reporter transposon. The assay scores transposition events as blue microcolonies, papillae, growing within otherwise whitish Escherichia coli colonies on indicator plates. We developed the assay using phage Mu transposition as a test model and validated the platform using various MuA transposase mutants. For further validation and to illustrate universality, we introduced IS903 transposition system components into the assay. The developed assay is adjustable to a desired level of initial transposition via the control of a plasmid-borne E. coli arabinose promoter. In practice, the transposition frequency is modulated by varying the concentration of arabinose or glucose in the growth medium. We show that variable levels of transpositional activity can be analysed, thus enabling straightforward screens for hyper- or hypoactive transposase mutants, regardless of the original wild-type activity level. Conclusions The established universal papillation assay platform should be widely applicable to a

  11. Regional water quality management for the Dong Nai River Basin, Vietnam.

    Science.gov (United States)

    Grayman, W M; Day, H J; Luken, R

    2003-01-01

    A three-year study that started solely as an industrial pollution reduction effort in Dong Nai Province of Vietnam expanded into an ongoing regional river basin water quality management effort. The project was a cooperative effort between the United Nations (UNDP and UNIDO) and the Federal and Provincial governments in Vietnam. A comprehensive approach was used to assess the impacts and strategies for reducing industrial, municipal and agricultural pollution to the water, air and land. The strategy was based upon use of knowledge in four subject areas, economics, ecology, technology and institutions, integrated within a framework for regional environmental quality management, sometimes called Areawide Environmental Quality Management (AEQM). Dong Nal Province encompasses a major developing area immediately north of Ho Chi Minh City. The land area chosen for the AEQM study is the 1,400 square kilometre region in and around Bien Hoa that drains into the Dong Nai River. The Dong Nai River serves many purposes including navigation, fisheries and a water supply for both the Province and Ho Chi Minh City. Extensive industrial and residential development was underway and was projected to increase in the coming decade. A strategy for the control of pollution from liquid, gaseous and solid wastes for the period 1998 to 2010 in Dong Nai Province was developed.

  12. Different Points of View Concerning the Didactic Transposition

    OpenAIRE

    2011-01-01

    The present article treats the concept of Didactic Transposition, taking as reference the work of Yves Chevallard, La transposición didáctica: del saber sabio al saber enseñado (2005). We compared the adduction of the concept in several works, such as thesis, dissertations and articles, and discussed the multiple impressions concerning the process of didactic transposition. These papers show that the conceptualizations are not well defined, entailing dubiousness and discussions. Some differen...

  13. Surgical preparation of a permanent carotid transposition in sheep

    OpenAIRE

    Gouvêa, Liana Villela de; Novais, Ernane de Paiva Ferreira; Leite, Ceci Ribeiro; Ximenes, Fábio Henrique Bezerra; de Almeida, Ricardo Miyasaka; Molás, Renato Bizinoto; Palermo, João Gabriel Cesar; Silva, Carlos Eduardo Vasconcelos da; Borges,José Renato Junqueira; Lima, Eduardo Maurício Mendes de; Godoy, Roberta Ferro de

    2011-01-01

    In large animal research, when frequent sampling of arterial blood is needed, the carotid artery transposition is the most used technique. The objective of this paper is to describe a new technique for carotid artery transposition in sheep and evaluate its effectiveness using the echo-Doppler ultrasound. The animals enrolled in this study had their carotid surgically elevated to the subcutaneous level, by suturing underneath muscles sternocephalic and brachiocephalic. None of the ...

  14. Regulation of mariner transposition: the peculiar case of Mos1.

    Directory of Open Access Journals (Sweden)

    Jérôme Jaillet

    Full Text Available BACKGROUND: Mariner elements represent the most successful family of autonomous DNA transposons, being present in various plant and animal genomes, including humans. The introduction and co-evolution of mariners within host genomes imply a strict regulation of the transposon activity. Biochemical data accumulated during the past decade have led to a convergent picture of the transposition cycle of mariner elements, suggesting that mariner transposition does not rely on host-specific factors. This model does not account for differences of transposition efficiency in human cells between mariners. We thus wondered whether apparent similarities in transposition cycle could hide differences in the intrinsic parameters that control mariner transposition. PRINCIPAL FINDINGS: We find that Mos1 transposase concentrations in excess to the Mos1 ends prevent the paired-end complex assembly. However, we observe that Mos1 transposition is not impaired by transposase high concentration, dismissing the idea that transposase over production plays an obligatory role in the down-regulation of mariner transposition. Our main finding is that the paired-end complex is formed in a cooperative way, regardless of the transposase concentration. We also show that an element framed by two identical ITRs (Inverted Terminal Repeats is more efficient in driving transposition than an element framed by two different ITRs (i.e. the natural Mos1 copy, the latter being more sensitive to transposase concentration variations. Finally, we show that the current Mos1 ITRs correspond to the ancestral ones. CONCLUSIONS: We provide new insights on intrinsic properties supporting the self-regulation of the Mos1 element. These properties (transposase specific activity, aggregation, ITR sequences, transposase concentration/transposon copy number ratio... could have played a role in the dynamics of host-genomes invasion by Mos1, accounting (at least in part for the current low copy number of

  15. MERCURY CONTAMINATION OF SUBSISTENCE FISHERIES ON TRIBAL LANDS: A PARTNERSHIP OF ORD, REGION 8 AND CHEYENNE RIVER SIOUX RESERVATION

    Science.gov (United States)

    In a prior collaborative 3 year study with the Cheyenne River Sioux Tribe Department of Environmental Protection (CRST DEP), and the Agencies' Environmental Response Team, RegionVIII investigated Hg levels in fish tissues from the Cheyenne River and Lake Oahe in South Dakota. In...

  16. Modeling of nitrobenzene in the river with ice process in high-latitude regions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To deal with the accidental release of pollutants into frozen rivers, those rivers in high-latitude regions should be treated differently. Pollutants could be stored up in the ice and released when the ice melts in spring, perhaps resulting in secondary pollution in the river. A water quality model of nitrobenzene has been developed in this paper to assess the influence on river water quality due to the freezing process. The model is made up of three modules: thermodynamic module, hydrodynamic module and water quality module. The thermodynamic module considers the complex heat exchange processes between the water body and the atmosphere, the water body and the river bed, the water body and the ice cover, and so on. The growth of the ice cover is simulated in a simplified form whilst taking consideration of heat balance. The hydrodynamic model uses the Saint-Venant equations in non-constant flow and the influence of the ice cover is measured. The degradation, diffusion, absorption and desorption, and the influence of the freezing process are incorporated in the water quality module and the concept of Con- tinuously Stirred Tanked Reactors (CSTRs) model is applied in the model construction. The model has been applied to supporting the management of accidental pollution in the Songhua River. The model was calibrated and validated with monitored data. Regional sensitivity analysis based on a task-based Hornberger-Spear-Young (HSY) algorithm was carried out to examine the model structure and the re- sult showed that the model could describe the system very well. Then the conditioned model was ap- plied to predicting the concentration of nitrobenzene in the water when the ice melted in spring. The predictive result showed that the release of pollutants in the ice could lead to an increase in the con- centration of pollutants in the water, but the increase would be very small because there was only a small amount of pollutants stored in the ice. A secondary pollution

  17. Modeling of nitrobenzene in the river with ice process in high-latitude regions

    Institute of Scientific and Technical Information of China (English)

    SUN PengCheng; ZENG SiYu; CHEN JiNing

    2009-01-01

    To deal with the accidental release of pollutants into frozen rivers,those rivers in high-latitude regions should be treated differently.Pollutants could be stored up in the ice and released when the ice melts in spring,perhaps resulting in secondary pollution in the river.A water quality model of nitrobenzene has been developed in this paper to assess the influence on river water quality due to the freezing process.The model is made up of three modules:thermodynamic module,hydrodynamic module and water quality module.The thermodynamic module considers the complex heat exchange processes between the water body and the atmosphere,the water body and the river bed,the water body and the ice cover,and so on.The growth of the ice cover is simulated in a simplified form whilst taking consideration of heat balance.The hydrodynamic model uses the Saint-Venant equations in non-constant flow and the influence of the ice cover is measured.The degradation,diffusion,absorption and desorption,and the influence of the freezing process are incorporated in the water quality module and the concept of Continuously Stirred Tanked Reactors (CSTRs) model is applied in the model construction.The model has been applied to supporting the management of accidental pollution in the Songhua River.The model was calibrated and validated with monitored data.Regional sensitivity analysis based on a task-based Hornberger-Spear-Young (HSY) algorithm was carried out to examine the model structure and the result showed that the model could describe the system very well.Then the conditioned model was applied to predicting the concentration of nitrobenzene in the water when the ice melted in spring.The predictive result showed that the release of pollutants in the ice could lead to an increase in the concentration of pollutants in the water,but the increase would be very small because there was only a small amount of pollutants stored in the ice.A secondary pollution could therefore be avoided

  18. Cavo-portal transposition in rat: a new simple model

    Directory of Open Access Journals (Sweden)

    Andorno Enzo

    2007-08-01

    Full Text Available Abstract Background Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat. Methods Spontaneous porto-systemic shunts are induced by subcutaneous transposition of the spleen. The presence of porto-caval shunts through the spleen permits the interruption of the main portal vein without splanchnic hemodynamic consequences. Cavo-portal transposition is achieved by anastomosing the inferior vena cava and the main portal vein after division of the pancreatic-duodenal vein. Results Selective angiography revealed total splanchnic blood diversion to the systemic venous circulation through the neoformed collaterals; macroscopical examination showed the absence of any signs of acute portal hypertension with normal liver and gut appearance. Conclusion This model of cavoportal transposition is simple, effective and it simulates the clinical hemodynamic condition since the porto-systemic shunts induced by splenic subcutaneous transposition correspond to the physiological inframesocolic collaterals during chronic portal thrombosis in man.

  19. Tooth transposition: a descriptive study in a 547-patient sample.

    Science.gov (United States)

    Bourzgui, Farid; Sebbar, Mourad; Ait Ikiss, Jamila; Hamza, Mouna; Abidine, Zouhair; El Quars, Farid

    2012-09-01

    The aim of this investigation was to study the prevalence of tooth transposition in a population of orthodontic patients. A total of 547 patient records from our dentofacial orthopedics department were consulted. Each file included clinical observations, panoramic radiography, lateral cephalograms and dental casts. Patients with incomplete or poorly kept orthodontic records were excluded from the sample, as were those with unreadable panoramic radiographs. The classification of tooth transpositions used in the study was that first proposed by S. Peck and L. Peck in 1995. Computerized statistical analysis was performed using Epi-Info 6.0. The prevalence of tooth transposition was 2%, with the female population more heavily affected (64%). Tooth transposition occurred only in the maxillary arch. Of all the teeth, the canines were the most involved in this anomaly (100%). Transposition was associated with tooth agenesis in 18% of cases, peg lateral incisors in 27%, and persistent deciduous teeth in 18%. The prevalence of tooth transposition in this study population remained low, but was nonetheless higher than that found in most published investigations. Copyright © 2012 CEO. Published by Elsevier Masson SAS. All rights reserved.

  20. [Evaluation on sustainability of forest resources in Bailong River forest region, Gansu Province].

    Science.gov (United States)

    Guo, Zhenggang; Cheng, Guodong; Wu, Bingli; Chen, Yuqi; Sun, Xuegang

    2003-09-01

    Based on the theories of sustainable development of forest resources, this paper constructed an index system for the integrative evaluation on the sustainability of forest resources in Bailon River forest region of Gansu Province. After calculated the index values of five strategic levels and twenty measure levels, the degree of harmony (DH) was obtained, with which, the sustainability of test forest resources could be evaluated. The DH value was 0.5320 in 1996 and 0.6100 in 2000, which was smaller than the theoretic value of 0.7000, and hence, this forest region belonged to non-sustainable development, but made some progress for its sustainability.

  1. Regional assessment of the hydropower potential of rivers in West Africa

    Science.gov (United States)

    Kling, Harald; Stanzel, Philipp; Fuchs, Martin

    2016-04-01

    The 15 countries of the Economic Community of West African States (ECOWAS) face a constant shortage of energy supply, which limits sustained economic growth. Currently there are about 50 operational hydropower plants and about 40 more are under construction or refurbishment. The potential for future hydropower development - especially for small-scale plants in rural areas - is assumed to be large, but exact data are missing. This study supports the energy initiatives of the "ECOWAS Centre for Renewable Energy and Energy Efficiency" (ECREEE) by assessing the hydropower potential of all rivers in West Africa. For more than 500,000 river reaches the hydropower potential was computed from channel slope and mean annual discharge. In large areas there is a lack of discharge observations. Therefore, an annual water balance model was used to simulate discharge. The model domain covers 5 Mio km², including e.g. the Niger, Volta, and Senegal River basins. The model was calibrated with observed data of 410 gauges, using precipitation and potential evapotranspiration data as inputs. Historic variations of observed annual discharge between 1950 and 2010 are simulated well by the model. As hydropower plants are investments with a lifetime of several decades we also assessed possible changes in future discharge due to climate change. To this end the water balance model was driven with bias-corrected climate projections of 15 Regional Climate Models for two emission scenarios of the CORDEX-Africa ensemble. The simulation results for the river network were up-scaled to sub-areas and national summaries. This information gives a regional quantification of the hydropower potential, expected climate change impacts, as well as a regional classification for general suitability (or non-suitability) of hydropower plant size - from small-scale to large projects.

  2. An elusive search for regional flood frequency estimates in the River Nile basin

    Directory of Open Access Journals (Sweden)

    P. Nyeko-Ogiramoi

    2012-09-01

    Full Text Available Estimation of peak flow quantiles in ungauged catchments is a challenge often faced by water professionals in many parts of the world. Approaches to address such problem exist, but widely used techniques such as flood frequency regionalisation is often not subjected to performance evaluation. In this study, the jack-knifing principle is used to assess the performance of the flood frequency regionalisation in the complex and data-scarce River Nile basin by examining the error (regionalisation error between locally and regionally estimated peak flow quantiles for different return periods (QT. Agglomerative hierarchical clustering based algorithms were used to search for regions with similar hydrological characteristics. Hydrological data employed were from 180 gauged catchments and several physical characteristics in order to regionalise 365 identified catchments. The Generalised Extreme Value (GEV distribution, selected using L-moment based approach, was used to construct regional growth curves from which peak flow growth factors could be derived and mapped through interpolation. Inside each region, variations in at-site flood frequency distribution were modelled by regression of the mean annual maximum peak flow (MAF versus catchment area. The results showed that the performance of the regionalisation is heavily dependent on the historical flow record length and the similarity of the hydrological characteristics inside the regions. The flood frequency regionalisation of the River Nile basin can be improved if sufficient flow data of longer record length of at least 40 yr become available.

  3. Application of HEC-RAS for flood forecasting in perched river-A case study of hilly region, China

    Science.gov (United States)

    Sun, Pingping; Wang, Shuqian; Gan, Hong; Liu, Bin; Jia, Ling

    2017-04-01

    Flooding in small and medium rivers are seriously threatening the safety of human beings’ life and property. The simulation forecasting of the river flood and bank risk in hilly region has gradually become a hotspot. At present, there are few studies on the simulation of hilly perched river, especially in the case of lacking section flow data. And the method of how to determine the position of the levee breach along the river bank is not much enough. Based on the characteristics of the sections in hilly perched river, an attempt is applied in this paper which establishes the correlation between the flow profile computed by HEC-RAS model and the river bank. A hilly perched river in Lingshi County, Shanxi Province of China, is taken as the study object, the levee breach positions along the bank are simulated under four different design storm. The results show that the flood control standard of upper reach is high, which can withstand the design storm of 100 years. The current standard of lower reach is low, which is the flooding channel with high frequency. As the standard of current channel between the 2rd and the 11th section is low, levee along that channel of the river bank is considered to be heighten and reinforced. The study results can provide some technical support for flood proofing in hilly region and some reference for the reinforcement of river bank.

  4. National Assessment of Oil and Gas Project - Powder River Basin Province (033) Regions of Oil and Gas Potential

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Regions of high or low potential for oil and gas resources in the Powder River Basin generally indicate where continuous oil and gas resources are more or less...

  5. Impacts of Climatic Factors on Runoff Coefficients in Source Regions of the Huanghe River

    Institute of Scientific and Technical Information of China (English)

    CHEN Liqun; LIU Changming; LI Yanping; WANG Guoqiang

    2007-01-01

    Runoff coefficients of the source regions of the Huanghe River in 1956-2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which had attracted considerable attention. Climate changes have important impact on the water resources availability. From the view of water cycling, runoff coefficients are important indexes of water resources in a particular catchment. Kalinin baseflow separation technique was improved based on the characteristics of precipitation and streamflow. After the separation of runoff coefficient (R/P), baseflow coefficient (Br/P) and direct runoff coefficient (Dr/P) were estimated. Statistic analyses were applied to assessing the impact of precipitation and temperature on runoff coefficients (including Dr/P,Br/P and R/P). The results show that in the source regions of the Huanghe River, mean annual baseflow coefficient was higher than mean annual direct runoff coefficient. Annual runoff coefficients were in direct proportion to annual precipitation and in inverse proportion to annual mean temperature. The decrease of runoff coefficients in the 1990s was closely related to the decrease in precipitation and increase in temperature in the same period. Over different sub-basins of the source regions of the Huanghe River, runoff coefficients responded differently to precipitation and temperature. In the area above Jimai Hydrologic Station where annual mean temperature is -3.9 ℃, temperature is the main factor influencing the runoff coefficients. Runoff coefficients were in inverse relation to temperature, and precipitation had nearly no impact on runoff coefficients. In subbasin between Jimai and Maqu Hydrologic Station Dr/P was mainly affected by precipitation while R/P and Br/P were both significantly influenced by precipitation and temperature. In the area between Maqu and Tangnaihai hydrologic stations all the three runoff coefficients increased with the rising

  6. End-member river water composition in the acidified Adirondack Region, Northern New York, USA

    Directory of Open Access Journals (Sweden)

    Jeffrey R. Chiarenzelli

    2014-11-01

    New hydrological insights for the region: Samples collected during average discharge volumes documented chemical gradients corresponding to bedrock spatial distribution. These trends were muted during both stormflow and baseflow, and imply that other factors influence water chemistry during high and low-flow events. Our study documents an example of event river chemistry responding less to extremes of flow or variation in underlying geology than anticipated. During the stormflow sampling one sample had elevated specific conductance (160.4 μS cm−1 and pH (8.21. This data, anomalous geochemistry, and images from Google Earth suggest that the river chemistry is sporadically impacted by discharge from a dolostone quarry located 6 km upstream during runoff events.

  7. No-Go Zones for Mariner Transposition

    Science.gov (United States)

    2016-01-01

    ABSTRACT The property of transposons to randomly insert into target DNA has long been exploited for generalized mutagenesis and forward genetic screens. Newer applications that monitor the relative abundance of each transposon insertion in large libraries of mutants can be used to evaluate the roles in cellular fitness of all genes of an organism, provided that transposition is in fact random across all genes. In a recent article, Kimura and colleagues identified an important exception to the latter assumption [S. Kimura, T. P. Hubbard, B. M. Davis, M. K. Waldor, mBio 7(4):e01351-16, 2016, doi:10.1128/mBio.01351-16]. They provide evidence that the Mariner transposon exhibits locus-specific site preferences in the presence of the histone-like nucleoid structuring protein H-NS. This effect was shown to bias results for important virulence loci in Vibrio cholerae and to result in misidentification of genes involved in growth in vitro. Fortunately, the bulk of this bacterium’s genome was unaffected by this bias, and recognizing the H-NS effect allows filtering to improve the accuracy of the results. PMID:27729512

  8. Tibiofibula Transposition in High-Energy Fractures

    Directory of Open Access Journals (Sweden)

    Peter R. Loughenbury

    2016-01-01

    Full Text Available We report two cases of failed attempts at closed reduction of high-energy tibial fractures with an associated fibula fracture. The first case was a 39-year-old male involved in high-speed motorbike collision, while the second was a 14-year-old male who injured his leg following a fall of three metres. Emergency medical services at the scenes of the accidents reported a 90-degree valgus deformity of the injured limb and both limbs were realigned on scene and stabilized. Adequate alignment of the tibia could not be achieved by manipulation under sedation or anaesthesia. Open reduction and exposure of the fracture sites revealed that the distal fibula fragment was “transposed” and entrapped in the medulla of the proximal tibial fragment. Reduction required simulation of the mechanism of injury in order to disengage the fragments and allow reduction. Tibiofibula transposition is a rare complication of high-energy lower limb fractures which has not previously been reported and may prevent adequate closed reduction. Impaction of the distal fibula within the tibial medulla occurs as the limb is realigned by paramedic staff before transfer to hospital. We recommend that when this complication is identified the patient is transferred to the operating room for open reduction and stabilization of the fracture.

  9. Health impact assessment of marine emissions in Pearl River Delta region.

    Science.gov (United States)

    Lai, H K; Tsang, H; Chau, J; Lee, C H; McGhee, S M; Hedley, A J; Wong, C M

    2013-01-15

    Global marine vessels emissions are adversely affecting human health particularly in southeast Asia. But health burdens from both ocean- and river-going vessels in Pearl River Delta (PRD) regions are not quantified. We estimated the potential health impacts using pooled relative risks of mortality and hospital admissions in China, and the model derived concentrations of sulfur dioxide (SO₂), particulate matter (PM₁₀), nitrogen dioxide (NO₂) and ozone (O₃) due to vessels emissions. SO₂ concentrations due to marine emissions in Hong Kong were 13.6 μg m⁻³ compared with 0.7 μg m⁻³ in PRD regions that were far from the marine vessels. In PRD regions, the estimated annual numbers (per million people) of excess deaths from all natural causes and hospital admissions from cardiorespiratory causes attributable to SO₂, NO₂, O₃ and PM₁₀ combined from marine emissions were 45 and 265 respectively. Marine emission control measures could contribute a large reduction in mortality and hospital admissions in PRD regions especially in Hong Kong.

  10. Population structure and genetic diversity of Sinibrama macrops from Ou River and Ling River based on mtDNA D-loop region analysis, China.

    Science.gov (United States)

    Zhao, Liangjie; Chenoweth, Erica L; Liu, Qigen

    2017-01-27

    In order to understand the influence of human activities such as habitat fragmentation on freshwater fish population evolution, we investigated and compared the genetic diversity and phylogeography of Sinibrama macrops populations in the Oujiang River and Ling River. Mitochondrial control region sequences (D-loop region) of 131 specimens from six populations were obtained and analyzed. The diversity of main stream in the Ou River was lower than that in Ling River. Changtan population showed the lowest diversity (H = 0.646 ± 0.077; π = 0.00060 ± 0.00820). Pairwise FST, gene flow (Nm), and genetic distance (Da) indicated that Longquan and Changtan significantly differentiate from other populations. Nested clade phylogeographical analysis (NCPA) showed some clades and total cladogram experienced isolation by distance. In conclusion, the populations from severely fragmented Ou River have the lower diversity and more intense differentiation than that from the mainstream of Ling River, Changtan population present the lowest diversity and were isolated by the dam construction.

  11. ENSO signals in South America. Rains and floods in the Parana River region during colonial times

    Energy Technology Data Exchange (ETDEWEB)

    Del Rosario Prieto, M. [Unit of Environmental History, Argentine Institute of Snow, Glaciers and Environmental Sciences IANIGLA CRICYT, Ruiz Leal s/n, Parque Gral San Martin, 5500 Mendoza (Argentina)

    2007-07-15

    Several studies show that the El Nino-Southern Oscillation (ENSO) is an important factor in determining interannual rainfall variability in South America. This signal is detected in the region including Northeastern Argentina, Uruguay and part of southern Brazil, in the form of excessive rains and big floods in the regional rivers. To check that this relationship was similar in the past the objectives of this paper were to construct a time series of large floods in the Parana River region from documentary records, during the sixteenth to eighteenth centuries, and to evaluate the relationship between that historical record of extreme floods, the ENSO documentary evidence (Ortlieb, The Documented Historical Record of El Nino Events in Peru: An Update of the Quinn Record (Ortlieb, sixteenth through nineteenth centuries, Diaz and Markgraf, (eds.), El Nino and the southern oscillation. Multiscale variability and global and regional Impacts. Cambridge University Press, pp. 207-295, 2001; Quinn and Neal, The historical record of El Nino events, Bradley and Jones (eds.), Climate since a.d. 1500, Routledges, pp. 623-648, 1992) and the temperature index of the Pacific Ocean (Mann ME et al., Global temperature patterns in past centuries: an interactive presentation, IGBP pages/world data center for paleoclimatology data contribution series no. 2000-075. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA, 2000). Considering that the period 1904-2000, where 11 out of 16 floods occurred during El Nino events, it can be concluded that the proportion of years with exceptional flow volume in the Parana River in years with El Nino events in the seventeenth and eighteenth centuries was relatively lower than that of the twentieth century. The reason for this difference is discussed.

  12. Investigation of the sources and formation mechanisms of regional haze in autumn over Pearl River Delta region, China

    Science.gov (United States)

    Zhou, S.; Wang, X.; Fan, Q.; Fan, S.; Chen, L.; Chang, M.; Huang, M.

    2015-12-01

    China has experienced severe haze and visibility degradation problems in recent years accompanying with rapid urbanization and industrialization. In this study, daily fine aerosol samples were concurrently collected during 01-29 October, 2014 in four sites (2 urban sites, 1 upwind site and 1 downwind site) in the Pearl River Delta (PRD) region (Figure 1), a mega metropolitan area and manufacturing hub in south China. Main chemical components of PM2.5 including sulfate, nitrate, ammonium, organic carbon, element carbon and elements, as well as individual particles morphology and mixing state and atmospheric boundary layer information were obtained and analyzed to investigate the sources and evolution mechanisms of typical haze events in the PRD region. The preliminary results showed that daily average PM2.5 concentrations varied from 25.4 to 174.8 μg m-3 with an average PM2.5 concentration of 64.5 μg m-3. We noted that PM2.5 concentrations in the downwind site were slightly higher than those in the upwind and urban sites during the haze episodes, indicating the formation and evolution of fine particles during the transport. Further detailed studies, including interpreting observational data and WRF/Chem model simulation, will be carried out to understand the sources and evolution mechanisms of the typical autumn regional haze in the PRD region.

  13. Problems of communicating radiation doses to aboriginal members of the public in the Alligator Rivers Region

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, D. (Northern Land Council, Darwin (Australia))

    1985-04-01

    Since the early 1970s, Aboriginal people of the Alligator Rivers Region have had to come to grips with the effects of uranium mining at Nabarlek and Ranger. One element in their cost-benefit approach to mine operations has been the expectation that bush foods in the region will not be contaminated by the mining operations. Recent studies on radionuclide concentrations in freshwater mussels (Velesunio angasi) in the region have shown this species, and perhaps others, to be efficient accumulators of radium. Information concerning natural radium accumulation in mussels and accompanying health risk estimates have been conveyed to Aboriginal people of the area and such information transfer has not been without its problems. Application of the ALARA principle to environmental management of the effluent pathways needs to consider Aboriginal expectations.

  14. Urbanization signatures in strong versus weak precipitation over the Pearl River Delta metropolitan regions of China

    Energy Technology Data Exchange (ETDEWEB)

    Li Weibiao; Chen Sheng; Wen Zhiping; Wang Baomin [Department of Atmospheric Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Chen Guixing; Sha Weimin [Department of Geophysics, Graduate School of Science, Tohoku University, Sendai (Japan); Luo Cong; Feng Yerong, E-mail: eeslwb@mail.sysu.edu.cn [Guangzhou Central Meteorological observatory, Guangzhou 510080 (China)

    2011-07-15

    We assess the issues of urban effects on the precipitation over the Pearl River Delta (PRD) metropolitan regions of China. The spatial and temporal variations of strong versus weak precipitation over the PRD and surrounding nonurban areas are investigated. The results show that the urbanization signatures in strong precipitation are significantly different from those in weak precipitation over the urban areas. The PRD experiences more strong precipitation but less weak precipitation compared to surrounding nonurban regions. In addition, the strong precipitation over the PRD displays a pronounced seasonal variation. The seasonality of weak precipitation, however, is much weaker over the PRD compared to the surrounding nonurban regions. Moreover, a strengthening in the precipitation intensity, a reduction in the rainfall frequency and an increase in the convective precipitation as well as the afternoon precipitation are found over the urban areas, which are probably associated with the abundance in strong precipitation and the deficit in weak precipitation over the PRD.

  15. Continental and sea surface temperature variability in southeast Africa (Zambezi River region) since MIS 3

    Science.gov (United States)

    Castañeda, I. S.; Tjallingii, R.; Wang, Y. V.; Mets, A.; van der Lubbe, J.; Brummer, G.; Sinninghe Damste, J. S.; Schneider, R. R.; Schouten, S.

    2010-12-01

    At present, few paleoclimate records exist from the region of southeast Africa. The continental climate history of southeast Africa is of much interest since this region falls under the influence of both the Intertropical Convergence Zone (ITCZ) and Congo Air Boundary (CAB) and likely experienced considerably different hydrological conditions when glacial conditions prevailed. Likewise, the paleoceanographic history of the Mozambique Channel of the coast of southeast Africa is of much interest since mesoscale eddies (Agulhas rings) formed in this region transport and release warm and saline Indian Ocean waters into the South Atlantic influencing the buoyancy of Atlantic thermocline waters, deep-water formation, and Atlantic Meridional Overturning Circulation. Sea surface temperatures (SST) of the southern Indian Ocean are additionally important for modulating precipitation in southeast Africa. Here, we utilize multiple organic (TEX86, BIT Index, MBT, CBT) and inorganic (XRF core scanning) geochemical proxies on a sediment core collected from near the Zambezi River (core 64PE304-80; -18.24 °S, 37.87 °E) to examine continental conditions within the Zambezi River catchment as well as the SST history of the Mozambique Channel. Throughout the ~38 kyr record of 64PE304-80, variations in the BIT Index, a proxy for marine vs. soil organic matter input, closely track changes in the log (Ca/Ti) ratio, a proxy for marine vs. lithogenic input. These records indicate increased lithogenic/soil OM contributions in the Late Pleistocene portion of the record whereas the Holocene is characterized by increased marine contributions. This pattern likely reflects closer proximity of the Zambezi river mouth and transport of terrestrial material to the coring site during the last glacial sea-level lowstand. A particularly interesting feature of these records is pronounced millennial-scale fluctuations occurring within Marine Isotope Stages (MIS) 2 and 3, which posses a similar structure

  16. Impact of nitrous acid chemistry on air quality modeling results over the Pearl River Delta region

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2011-05-01

    Full Text Available The impact of nitrous acid chemistry on regional ozone and particulate matter in Pearl River Delta region was investigated using the Community Mutilscale Air Quality modeling system and the CB05 mechanism. Model simulations were conducted for a ten-day period in October 2004. Compared with available observed data, the model performance for NOx, SO2, PM10, and sulfate is reasonably good; however, predictions of HONO are an order of magnitude lower than observed data. The CB05 mechanism contains several homogenous reactions related to nitrous acid. To improve the model performance for nitrous acid, direct emissions, two heterogeneous reactions, and two surface photolysis reactions were incorporated into the model. The inclusion of the additional formation pathways significantly improved simulated nitrous acid compared with observed data. The addition of nitrous acid sources enhance daily maximum 8-h ozone by up to 6 ppb V (8 % and daily mean PM2.5 by up to 17 μg m−3 (12 %. They also affected ozone control strategy in Pearl River Delta region.

  17. Comparison of the optical properties of dissolved organic matter in two river-influenced coastal regions of the Canadian Arctic

    Science.gov (United States)

    Retamal, Leira; Vincent, Warwick F.; Martineau, Christine; Osburn, Christopher L.

    2007-03-01

    The optical characteristics of coloured dissolved organic matter (CDOM) were analyzed in the Great Whale River and adjacent Hudson Bay (55° N, 77° W) in the eastern Canadian Low Arctic, and in the Mackenzie River and adjacent Beaufort Sea in the western Canadian High Arctic (70° N, 133° W). Sampling was during ice-free open water conditions. Both rivers contained high concentrations of dissolved organic carbon (3 and 6 mg DOC l -1 in the Great Whale River and Mackenzie River, respectively) and CDOM ( a320 of 11 and 14 m -1), resulting in a substantial load of organic matter to their coastal seas. There were pronounced differences in the CDOM characteristics of the two rivers, notably in their synchronous fluorescence scans (SFS). The latter showed that the Mackenzie River was depleted in humic materials, implying a more mature catchment relative to the younger, more recently glaciated Great Whale River system. SFS spectra had a similar shape across the freshwater-saltwater transition zone of the Great Whale plume, and DOC was linearly related to salinity implying conservative mixing and no loss by flocculation or biological processes across the salt front. In contrast, there were major differences in SFS spectral shape from the Mackenzie River to the freshwater-influenced coastal ocean, with a marked decrease in the relative importance of fulvic and humic acid materials. The SFS spectra for the coastal Beaufort Sea in September-October strongly resembled those recorded for the Mackenzie River during the high discharge, CDOM-rich, snowmelt period in June, but with some loss of autochthonous materials. These results are consistent with differences in freshwater residence time between the Mackenzie River and Great Whale River coastal ocean systems. Models of arctic continental shelf responses to present and future climate regimes will need to consider these striking regional differences in the organic matter content, biogeochemistry and optics between waters from

  18. Application of hydrological models in a snowmelt region of Aksu River Basin

    Directory of Open Access Journals (Sweden)

    Ouyang Rulin

    2008-12-01

    Full Text Available This study simulated and predicted the runoff of the Aksu River Basin, a typical river basin supplied by snowmelt in an arid mountain region, with a limited data set and few hydrological and meteorological stations. Two hydrological models, the snowmelt-runoff model (SRM and the Danish NedbØr-AfstrØmnings rainfall-runoff model (NAM, were used to simulate daily discharge processes in the Aksu River Basin. This study used the snow-covered area from MODIS remote sensing data as the SRM input. With the help of ArcGIS software, this study successfully derived the digital drainage network and elevation zones of the basin from digital elevation data. The simulation results showed that the SRM based on MODIS data was more accurate than NAM. This demonstrates that the application of remote sensing data to hydrological snowmelt models is a feasible and effective approach to runoff simulation and prediction in arid unguaged basins where snowmelt is a major runoff factor.

  19. Regional L-Moment-Based Flood Frequency Analysis in the Upper Vistula River Basin, Poland

    Science.gov (United States)

    Rutkowska, A.; Żelazny, M.; Kohnová, S.; Łyp, M.; Banasik, K.

    2016-05-01

    The Upper Vistula River basin was divided into pooling groups with similar dimensionless frequency distributions of annual maximum river discharge. The cluster analysis and the Hosking and Wallis (HW) L-moment-based method were used to divide the set of 52 mid-sized catchments into disjoint clusters with similar morphometric, land use, and rainfall variables, and to test the homogeneity within clusters. Finally, three and four pooling groups were obtained alternatively. Two methods for identification of the regional distribution function were used, the HW method and the method of Kjeldsen and Prosdocimi based on a bivariate extension of the HW measure. Subsequently, the flood quantile estimates were calculated using the index flood method. The ordinary least squares (OLS) and the generalised least squares (GLS) regression techniques were used to relate the index flood to catchment characteristics. Predictive performance of the regression scheme for the southern part of the Upper Vistula River basin was improved by using GLS instead of OLS. The results of the study can be recommended for the estimation of flood quantiles at ungauged sites, in flood risk mapping applications, and in engineering hydrology to help design flood protection structures.

  20. Implication of recent climate change for the hydrology of the source region of the Yellow River

    Science.gov (United States)

    Su, Fengge; Meng, Fancong; Tong, Kai

    2014-05-01

    The basin upstream of the Tangnahai station (UYE), with an area of 121972 km2, is known as the source region of the Yellow River (YR) which is the second largest river in China. The UYE accounts for about 16% of the YR basin area, but it produces about 38% of the total annual runoff, and thus is considered to be the "water tower" of the entire basin. The UYE has experienced a warming trend of 0.41°C/10y during 1961-2009. Accompanied by the warming climate, total discharge in the UYE has shown a decreasing trend over the past 49 years. In this work, we analyze the spatial-temporal changes of climate factors and water balance terms in the UYE during 1961-2009, including precipitation, temperature, runoff, evapotranspiration, snow cover extent, and terrestrial water storage change, from gauge observations, model simulations, and satellite retrievals. This work aims to better understand the water budget change characters in the UYE in relation to the climate factors in the past 5 decades. An improved understanding certainly has implications for the sustainable management of water resources not only for the UYE but also for the entire Yellow River basin.

  1. Application of hydrological models in a snowmelt region of Aksu River Basin

    Institute of Scientific and Technical Information of China (English)

    Ouyang Rulin; Ren Liliang; Cheng Weiming; Yu Zhongbo

    2008-01-01

    This study simulated and predicted the runoff of the Aksu River Basin, a typical river basin supplied by snowmelt in an arid mountain region, with a limited data set and few hydrological and meteorological stations. Two hydrological models, the snowmelt-runoff model (SRM) and the Danish Nedbφr-Afstrφmnings rainfall-runoff model (NAM), were used to simulate daily discharge processes in the Aksu River Basin. This study used the snow-covered area from MODIS remote sensing data as the SRM input. With the help of ArcGIS software, this study successfully derived the digital drainage network and elevation zones of the basin from digital elevation data. The simulation results showed that the SRM based on MODIS data was more accurate than NAM. This demonstrates that the application of remote sensing data to hydrological snowmelt models is a feasible and effective approach to runoff simulation and prediction in arid unguaged basins where snowmelt is a major runoff factor.

  2. Regional L-Moment-Based Flood Frequency Analysis in the Upper Vistula River Basin, Poland

    Science.gov (United States)

    Rutkowska, A.; Żelazny, M.; Kohnová, S.; Łyp, M.; Banasik, K.

    2017-02-01

    The Upper Vistula River basin was divided into pooling groups with similar dimensionless frequency distributions of annual maximum river discharge. The cluster analysis and the Hosking and Wallis (HW) L-moment-based method were used to divide the set of 52 mid-sized catchments into disjoint clusters with similar morphometric, land use, and rainfall variables, and to test the homogeneity within clusters. Finally, three and four pooling groups were obtained alternatively. Two methods for identification of the regional distribution function were used, the HW method and the method of Kjeldsen and Prosdocimi based on a bivariate extension of the HW measure. Subsequently, the flood quantile estimates were calculated using the index flood method. The ordinary least squares (OLS) and the generalised least squares (GLS) regression techniques were used to relate the index flood to catchment characteristics. Predictive performance of the regression scheme for the southern part of the Upper Vistula River basin was improved by using GLS instead of OLS. The results of the study can be recommended for the estimation of flood quantiles at ungauged sites, in flood risk mapping applications, and in engineering hydrology to help design flood protection structures.

  3. Regional contribution to PM1 pollution during winter haze in Yangtze River Delta, China.

    Science.gov (United States)

    Tang, Lili; Yu, Hongxia; Ding, Aijun; Zhang, Yunjiang; Qin, Wei; Wang, Zhuang; Chen, Wentai; Hua, Yan; Yang, Xiaoxiao

    2016-01-15

    To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%).

  4. Impact of lake-river connectivity and interflow on the Canadian RCM simulated regional climate and hydrology for Northeast Canada

    Science.gov (United States)

    Huziy, O.; Sushama, L.

    2017-02-01

    Lakes affect regional climate by modulating surface albedo, surface energy, and moisture budgets. This is especially important for regions such as Northeast Canada with approximately 10 % of the landmass covered by lakes, wetlands and rivers. From the regional hydrology perspective, interactions between lakes and rivers are important as streamflow patterns can be significantly modified by lake storage, and similarly lake levels can be modified by streamflows. In this study, using a suite of experiments performed with the fifth generation Canadian Regional Climate Model (CRCM5) driven by the European Centre for Medium range Weather Forecasting ERA40 reanalysis data at the lateral boundaries for the 1979-2010 period, lake-river-atmosphere interactions and their impact on the regional climate/hydrology of north-east Canada are assessed. In these CRCM5 simulations, a one-dimensional lake model represents lakes, while the rivers are modeled using a distributed routing scheme, and one of the simulations includes interflow, i.e. lateral flow of water in the soil layers. Comparison of CRCM5 simulations with and without lakes suggests significant differences in winter/summer precipitation and winter temperature for the study region. CRCM5 simulations performed with and without lake-river interactions suggest improved representation of streamflows when lake storage and routing are taken into account. Adding the interflow process leads to increased streamflows during summer and fall seasons for the majority of the rivers, causing modest changes to land-atmosphere interactions via modified soil moisture. The impact of interflow on streamflow, obtained in this study, is comparable to the impact of lake-atmosphere interactions on streamflows. This study clearly demonstrates the need for realistic representation of lake-river interactions in regional climate models for realistic simulation of regional hydrology, particularly streamflows.

  5. Characterization of the regional variability of flood regimes within the Omo-Gibe River Basin, Ethiopia

    Science.gov (United States)

    Yared, Adanech; Demissie, Solomon S.; Sivapalan, Murugesu; Viglione, Alberto; MacAlister, Charlotte

    2014-05-01

    Hydrological variability and seasonality is one of the Ethiopia's primary water resource management challenges. Variability is most obviously manifest in endemic, devastating droughts and floods. While the level of flooding is quite often extremely high and destroys human beings and property, in many cases flooding is of vital importance because the community benefits from flood recession agriculture. This is the case of the lower Omo plain whose agriculture is based on the regularity of the inundations due to flooding of the Omo Gibe River. The big flood in 2006, which caused death for more than 300 people and 2000 cattle, poses a dilemma. Flooding must be controlled and regulated in a way that the damages are reduced as much as possible but the flooding-related benefits are not lost. To this aim, characterization and understanding of hydrological variability of the Omo Gibe River basin is fundamental. The goal of this work is to extract the maximal amount of information on the hydrological variability and specially on the flooding regime from the few data available in the region. Because most of the basin is ungauged, hydrological information is reconstructed using the data from 9 gauged catchments. A daily water balance model has been developed, calibrated and validated for 9 gauged catchments and, subsequently, the parameters have been correlated to catchment characteristics in order to establish a functional relationship that allows to apply the model to ungauged catchments. Daily streamflow has been predicted for 15 ungauged catchments, which are assumed to comprehensively represent the hydrological variability of the Omo-Gibe River Basin. Even though both northern and southern catchments are affected by a strong seasonality of precipitation, with most of the rain falling in less than 3 months, most of the northern catchments are humid, while in the southern part of the Omo-Gibe River basin, the catchments are either humid, dry sub humid, semiarid or arid. As

  6. Identification of structural breaks in hydrological maxima time series in Paraguay River, Pantanal Region, Brazil.

    Science.gov (United States)

    Santos, Marcus; Lima, Carlos

    2016-04-01

    The hydrological time series of the Paraguay River located in the Pantanal region of Brazil exhibits a complex and interesting behavior, which includes long memory characteristics, monotonic trends, multiple breaks and strong seasonality. Particularly, several abrupt changes from low to high flows and vice versa have been observed on annual maxima time series and have been responsible for the major flood damages in the region, even more significant than the largest floods that occurred in the period post 1974. The year of 1974 is historically known as the year of the most significant flood impact in region, especially on agriculture and cattle. Therefore, the identification and attribution of such step changes in the series is of particular interest to improve the flood management systems across the region. Here we apply the cumulative sum (CUSUM) procedure to identify the timing of the abrupt changes. Preliminary results for the Ladario streamflow gauge reveal multiple structural changes in 1936 (high flows to low flows), 1961 (high/low), 1974 (low/high) and 1999 (high/low). Rainfall records were also analyzed and the results obtained suggest that the Paraguay River basin in its upper reach, monitored by Caceres gauging station (32,400 km²) and Cuiabá river basin (23,500 km²) are the factors that most contribute to low frequencies oscillations in the Ladario maxima time series (253,000 km²). These sub-basins are both located in the northern part of the catchment along with the boundary of the Amazon River basin, where the average rainfall is more expressive. In both basins the rainfall records show a structural break in 1973. Simple linear regression using rainfall and flow records in those sub-basins show that the rainfall data accounts for around 70% of the flow variance, indicating that the internal dynamics of the catchment plays a minor role on the streamflow variability. Low frequency variability is also observed in both rainfall series and may be the

  7. Regional precipitation trend analysis at the Langat River Basin, Selangor, Malaysia

    Science.gov (United States)

    Palizdan, Narges; Falamarzi, Yashar; Huang, Yuk Feng; Lee, Teang Shui; Ghazali, Abdul Halim

    2014-08-01

    Various hydrological and meteorological variables such as rainfall and temperature have been affected by global climate change. Any change in the pattern of precipitation can have a significant impact on the availability of water resources, agriculture, and the ecosystem. Therefore, knowledge on rainfall trend is an important aspect of water resources management. In this study, the regional annual and seasonal precipitation trends at the Langat River Basin, Malaysia, for the period of 1982-2011 were examined at the 95 % level of significance using the regional average Mann-Kendall (RAMK) test and the regional average Mann-Kendall coupled with bootstrap (RAMK-bootstrap) method. In order to identify the homogeneous regions respectively for the annual and seasonal scales, firstly, at-site mean total annual and separately at-site mean total seasonal precipitation were spatialized into 5 km × 5 km grids using the inverse distance weighting (IDW) algorithm. Next, the optimum number of homogeneous regions (clusters) is computed using the silhouette coefficient approach. Next, the homogeneous regions were formed using the K-mean clustering method. From the annual scale perspective, all three regions showed positive trends. However, the application of two methods at this scale showed a significant trend only in the region AC1. The region AC2 experienced a significant positive trend using only the RAMK test. On a seasonal scale, all regions showed insignificant trends, except the regions I1C1 and I1C2 in the Inter-Monsoon 1 (INT1) season which experienced significant upward trends. In addition, it was proven that the significance of trends has been affected by the existence of serial and spatial correlations.

  8. A regional neural network model for predicting mean daily river water temperature

    Science.gov (United States)

    Wagner, Tyler; DeWeber, Jefferson Tyrell

    2014-01-01

    Water temperature is a fundamental property of river habitat and often a key aspect of river resource management, but measurements to characterize thermal regimes are not available for most streams and rivers. As such, we developed an artificial neural network (ANN) ensemble model to predict mean daily water temperature in 197,402 individual stream reaches during the warm season (May–October) throughout the native range of brook trout Salvelinus fontinalis in the eastern U.S. We compared four models with different groups of predictors to determine how well water temperature could be predicted by climatic, landform, and land cover attributes, and used the median prediction from an ensemble of 100 ANNs as our final prediction for each model. The final model included air temperature, landform attributes and forested land cover and predicted mean daily water temperatures with moderate accuracy as determined by root mean squared error (RMSE) at 886 training sites with data from 1980 to 2009 (RMSE = 1.91 °C). Based on validation at 96 sites (RMSE = 1.82) and separately for data from 2010 (RMSE = 1.93), a year with relatively warmer conditions, the model was able to generalize to new stream reaches and years. The most important predictors were mean daily air temperature, prior 7 day mean air temperature, and network catchment area according to sensitivity analyses. Forest land cover at both riparian and catchment extents had relatively weak but clear negative effects. Predicted daily water temperature averaged for the month of July matched expected spatial trends with cooler temperatures in headwaters and at higher elevations and latitudes. Our ANN ensemble is unique in predicting daily temperatures throughout a large region, while other regional efforts have predicted at relatively coarse time steps. The model may prove a useful tool for predicting water temperatures in sampled and unsampled rivers under current conditions and future projections of climate

  9. Eco-environmental degradation in the source region of the Yellow River, Northeast Qinghai-Xizang Plateau.

    Science.gov (United States)

    Feng, Jianmin; Wang, Tao; Xie, Changwei

    2006-11-01

    The Yellow River is the second longest river in China and the cradle of the Chinese civilization. The source region of the Yellow River is the most important water holding area for the Yellow River, about 49.2% of the whole runoff comes from this region. However, for the special location, it is a region with most fragile eco-environment in China as well. Eco-environmental degradation in the source region of the Yellow River has been a very serious ecological and socially economic problem. According to census data, historical documents and climatic information, during the last half century, especially the last 30 years, great changes have taken place in the eco-environment of this region. Such changes are mainly manifested in the temporal-spatial changes of water environment, deglaciation, permafrost reduction, vegetation degeneracy and desertification extent, which led to land capacity decreasing and river disconnecting. At present, desertification of the region is showing an accelerating tendency. This paper analyzes the present status of eco-environment degradation in this region supported by GIS and RS, as well as field investigation and indoor analysis, based on knowledge, multi-source data is gathered and the classification is worked out, deals with their natural and anthropogenic causes, and points out that in the last half century the desertification and environmental degradation of this region are mainly attributed to human activities under the background of regional climate changes. To halt further degradation of the environment of this region, great efforts should be made to use land resources rationally, develop advantages animal agriculture and protect the natural grassland.

  10. Mapping hotspots of threatened species traded in bushmeat markets in the Cross-Sanaga rivers region.

    Science.gov (United States)

    Fa, John E; Farfán, Miguel Angel; Marquez, Ana Luz; Duarte, Jesús; Nackoney, Janet; Hall, Amy; Dupain, Jef; Seymour, Sarah; Johnson, Paul J; MacDonald, David W; Vargas, J Mario

    2014-02-01

    Bushmeat markets exist in many countries in West and Central Africa, and data on species sold can be used to detect patterns of wildlife trade in a region. We surveyed 89 markets within the Cross-Sanaga rivers region, West Africa. In each market, we counted the number of carcasses of each taxon sold. During a 6-month period (7594 market days), 44 mammal species were traded. Thirteen species were on the International Union for Conservation of Nature (IUCN) Red List or protected under national legislation, and at least 1 threatened species was traded in 88 of the 89 markets. We used these data to identify market groups that traded similar species assemblages. Using cluster analyses, we detected 8 market groups that were also geographically distinct. Market groups differed in the diversity of species, evenness of species, and dominant, prevalent, and characteristic species traded. We mapped the distribution of number of threatened species traded across the study region. Most threatened species were sold in markets nearest 2 national parks, Korup National Park in Cameroon and Cross River in Nigeria. To assess whether the threatened-species trade hotspots coincided with the known ranges of these species, we mapped the overlap of all threatened species traded. Markets selling more threatened species overlapped with those regions that had higher numbers of these. Our study can provide wildlife managers in the region with better tools to discern zones within which to focus policing efforts and reduce threats to species that are threatened by the bushmeat trade. © 2013 Society for Conservation Biology.

  11. Climate change and its driving effect on the runoff in the “Three-River Headwaters” region

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shifeng; HUA Dong; MENG Xiujing; ZHANG Yongyong

    2011-01-01

    Based on the precipitation and temperature data of the 12 meteorological stations in the “Three-River Headwaters” region and the observed runoff data of Zhimenda in the headwater sub-region of the Yangtze River,Tangnaihai in the headwater sub-region of the Yellow River and Changdu in the headwater sub-region of the Lancang River during the period 1965-2004,this paper analyses the trends of precipitation,temperature,runoff depth and carries out significance tests by means of Mann-Kendall-Sneyers sequential trend test.Makkink model is applied to calculate the potential evaporation.The runoff model driven by precipitation and potential evaporation is developed and the influence on runoff by climate change is simulated under different scenarios.Results show that during the period 1965-2004 the temperature of the “Three-River Headwaters” region is increasing,the runoff of the three hydrological stations is decreasing and both of them had abrupt changes in 1994,while no significant trend changes happen to the precipitation.The runoff model suggests that the precipitation has a positive effect on the runoff depth,while the potential evaporation plays a negative role.The influence of the potential evaporation on the runoff depth of the Lancang River is found to be the significant in the three rivers; and that of the Yellow River is the least.The result of the scenarios analysis indicates that although the precipitation and the potential evaporation have positive and negative effects on runoff relatively,fluctuated characteristics of individual effect on the runoff depth in specific situations are represented.

  12. Time-Series Analysis of Remotely-Sensed SeaWiFS Chlorophyll in River-Influenced Coastal Regions

    Science.gov (United States)

    Acker, James G.; McMahon, Erin; Shen, Suhung; Hearty, Thomas; Casey, Nancy

    2009-01-01

    The availability of a nearly-continuous record of remotely-sensed chlorophyll a data (chl a) from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) mission, now longer than ten years, enables examination of time-series trends for multiple global locations. Innovative data analysis technology available on the World Wide Web facilitates such analyses. In coastal regions influenced by river outflows, chl a is not always indicative of actual trends in phytoplankton chlorophyll due to the interference of colored dissolved organic matter and suspended sediments; significant chl a timeseries trends for coastal regions influenced by river outflows may nonetheless be indicative of important alterations of the hydrologic and coastal environment. Chl a time-series analysis of nine marine regions influenced by river outflows demonstrates the simplicity and usefulness of this technique. The analyses indicate that coastal time-series are significantly influenced by unusual flood events. Major river systems in regions with relatively low human impact did not exhibit significant trends. Most river systems with demonstrated human impact exhibited significant negative trends, with the noteworthy exception of the Pearl River in China, which has a positive trend.

  13. Effects of Crop Growth on Hydrological Pro cesses in River Basins and on Regional Climate in China

    Institute of Scientific and Technical Information of China (English)

    QIN Pei-Hua; CHEN Feng; XIE Zheng-Hui

    2013-01-01

    The regional climate model RegCM3 incorporating the crop model CERES, called the RegCM3−CERES model, was used to study the effects of crop growth and development on regional climate and hydrological processes over seven river basins in China. A 20-year numerical simulation showed that incorporating the crop growth and development processes improved the simulation of precipitation over the Haihe River Basin, Songhua jiang River Basin and Pearl River Basin. When compared with the RegCM3 control run, RegCM3−CERES reduced the negative biases of monthly mean temper-ature over most of the seven basins in summer, especially the Haihe River Basin and Huaihe River Basin. The simulated maximum monthly evapotranspiration for summer (JJA) was around 100 mm in the basins of the Yangtze, Haihe, Huaihe and Pearl Rivers. The seasonal and annual variations of water balance components (runoff, evapotranspiration and to-tal precipitation) over all seven basins indicate that changes of evapotranspiration agree well with total precipitation. Compared to the RegCM3, RegCM3−CERES simulations indicate reduced local water recycling rate over most of the seven basins due to lower evapotranspiration and greater water flux into these basins and an increased precipitation in the Heihe River Basin and Yellow River Basin, but reduced precipitation in the other five basins. Furthermore, a lower summer leaf area index (1.20 m2 m−2), greater root soil moisture (0.01 m3 m−3), lower latent heat flux (1.34 W m−2), and greater sensible heat flux (2.04 W m−2 ) are simulated for the Yangtze River Basin.

  14. Unilateral and bilateral dental transpositions in the maxilla

    DEFF Research Database (Denmark)

    Danielsen, Jakob Christian; Karimian, K; Ciarlantini, R;

    2015-01-01

    AIM: This was to elucidate dental and skeletal findings in individuals with unilateral and bilateral maxillary dental transpositions. MATERIAL AND METHODS: The sample comprised of radiographic materials from 63 individuals with maxillary dental transpositions from the Departments of Odontology...... and lateral incisor (Type 2). The dentitions were analysed regarding agenesis and dental morphological anomalies on panoramic radiographs, and craniofacial aspects were cephalometrically analysed on profile images The results were statistically evaluated. RESULTS: All groups demonstrated increased occurrences...... retrognathia (more pronounced in Type 1B). Type 2 showed a significant posterior inclination of the maxilla. CONCLUSION: Transpositions of maxillary canines involve dental and skeletal deviations. Dental deviations were predominantly taurodontic root morphology and agenesis. Regarding skeletal deviations...

  15. Chronology of Miocene Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

    Science.gov (United States)

    Dorsey, Rebecca J.; Fluette, Amy; McDougall, Kristin; Housen, Bernard A.; Janecke, Susanne U.; Axen, Gary J.; Shirvell, Catherine R.

    2007-01-01

    Late Miocene to early Pliocene deposits at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ± 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River.

  16. Regional Integrated Experiments on Air Quality over Pearl River Delta 2004 (PRIDE-PRD2004): Overview

    Science.gov (United States)

    Zhang, Y. H.; Hu, M.; Zhong, L. J.; Wiedensohler, A.; Liu, S. C.; Andreae, M. O.; Wang, W.; Fan, S. J.

    The aims of the Program of Regional Integrated Experiments on Air Quality over Pearl River Delta of China 2004 (PRIDE-PRD2004) were to characterize in depth the pollution, and to improve the understanding of the chemical and radiative processes in the atmosphere of Pearl River Delta (PRD) in South-Eastern China. This comprehensive program integrated ground-base in situ measurements, vertical observations (including aircraft) and model simulations. The intensive field campaign was conducted from 4 October to 5 November 2004 at two super-sites: an urban site in Guangzhou city (23.13°N, 113.26°E) and a non-urban site at Xinken (22.61°N, 113.59°E). They were coordinated with concurrent meteorological observations as well as measurements at stations of a regional monitoring network. Quality control and quality assurances, application of closure studies and observation-based modeling were the key elements of the research strategies for the PRIDE-PRD2004 campaign. Knowledge and understanding of the important issues, including 3-D distribution of air pollution, ozone formation process and its control strategies, sources of volatile organic compounds, chemical and physical characteristics and radiative properties of aerosols, and the important role of nitrous acid atmospheric chemistry, have been improved substantially by this study.

  17. Managing the three-rivers headwater region, china: from ecological engineering to social engineering.

    Science.gov (United States)

    Fang, Yiping

    2013-09-01

    The three-rivers headwater region (THRHR) of Qinghai province, China plays a key role as source of fresh water and ecosystem services for central and eastern China. Global warming and human activities in the THRHR have threatened the ecosystem since the 1980s. Therefore, the Chinese government has included managing of the THRHR in the national strategy since 2003. The State Integrated Test and Demonstration Region of the THRHR highlights the connection with social engineering (focus on improving people's livelihood and well-being) in managing nature reserves. Based on this program, this perspective attempts a holistic analysis of the strategic role of the THRHR, requirements for change, indices of change, and approaches to change. Long-term success of managing nature reserves requires effective combination of ecological conservation, economic development, and social progress. Thus, the philosophy of social engineering should be employed as a strategy to manage the THRHR.

  18. Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China

    Directory of Open Access Journals (Sweden)

    S. Situ

    2013-03-01

    Full Text Available In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC emission model (MEGAN v2.1. The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem is used to estimate the impacts of BVOC emissions on surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by ~3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou-Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.

  19. Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China

    Energy Technology Data Exchange (ETDEWEB)

    Situ, S.; Guenther, Alex B.; Wang, X. J.; Jiang, X.; Turnipseed, A.; Wu, Z.; Bai, J.; Wang, X.

    2013-12-05

    In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD) region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC) emission model (MEGAN v2.1). The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem) is used to estimate the impacts of BVOC emissions on surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by *3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou- Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.

  20. Examining the Impact of Nitrous Acid Chemistry on Ozone and PM over the Pearl River Delta Region

    Science.gov (United States)

    The impact of nitrous acid (HONO) chemistry on regional ozone and particulate matter in Pearl River Delta region was investigated using the community multiscale air quality (CMAQ) modeling system and the CB05 mechanism. Model simulations were conducted for a ten-day period in Oct...

  1. Emission inventory of anthropogenic air pollutants and VOC species in the Yangtze River Delta region, China

    Directory of Open Access Journals (Sweden)

    C. Huang

    2011-05-01

    Full Text Available The purpose of this study is to develop an emission inventory for major anthropogenic air pollutants and VOC species in the Yangtze River Delta (YRD region for the year 2007. A "bottom-up" methodology was adopted to compile the inventory based on major emission sources in the sixteen cities of this region. Results show that the emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, and NH3 in the YRD region for the year 2007 are 2392 kt, 2293 kt, 6697 kt, 3116 kt, 1511 kt, 2767 kt, and 459 kt, respectively. Ethylene, mp-xylene, o-xylene, toluene, 1,2,4-trimethylbenzene, 2,4-dimethylpentane, ethyl benzene, propylene, 1-pentene, and isoprene are the key species contributing 77 % to the total ozone formation potential (OFP. The spatial distribution of the emissions shows the emissions and OFPs are mainly concentrated in the urban and industrial areas along the Yangtze River and around Hangzhou Bay. The industrial sources, including power plants other fuel combustion facilities, and non-combustion processes contribute about 97 %, 86 %, 89 %, 91 %, and 69 % of the total SO2, NOx, PM10, PM2.5, and VOC emissions. Vehicles take up 12.3 % and 12.4 % of the NOx and VOC emissions, respectively. Regarding OFPs, the chemical industry, domestic use of paint & printing, and gasoline vehicles contribute 38 %, 24 %, and 12 % to the ozone formation in the YRD region.

  2. Recent temperature increase recorded in an ice core in the source region of Yangtze River

    Institute of Scientific and Technical Information of China (English)

    KANG ShiChang; ZHANG YongJun; QIN DaHe; REN JiaWen; ZHANG QiangGong; Bjorn GRIGHOLM; Paul A. MAYEWSKI

    2007-01-01

    Interests on climate change in the source region of Yangtze River have been raised since it is a region with the greatest warming over the Tibetan Plateau (TP). A 70-year history of precipitation δ18O has been recovered using an ice core record retrieved in a plat portion of the firn area in the Guoqu Glacier (33°34′37.8″N, 91°10′35.32″E, 5720 m a.s.l.), Mt. Geladaindong (the source region of Yangtze River), in November, 2005. By using a significant positive relationship between ice core δ18O record and summer air temperature (July to September) from the nearby meteorological stations, a history of summer air temperature has been reconstructed for the last 70 years. Summer temperature was relatively low in 1940s and high in 1950s to the middle of 1960s. The lowest temperature occurred in the middle of 1970s.Temperature was low in 1980s and dramatically increased since 1990s, keeping the trend to the beginning of the 21st century. The warming rate recorded in the ice core with 0.5°C/10 a since 1970s is much higher that that in the central TP and the Northern Hemisphere (NH), and it becomes 1.1°C/10 a since 1990s which is also higher than these from the central TP and the NH, reflecting an accelerated warming and a more sensitive response to global warming in the high elevation region.

  3. The KULTURisk Regional Risk Assessment methodology for flood risk: the case of Sihl river in Zurich

    Science.gov (United States)

    Ronco, Paolo; Bullo, Martina; Gallina, Valentina; Torresan, Silvia; Critto, Andrea; Zabeo, Alex; Semenzin, Elena; Buchecker, Matthias; Marcomini, Antonio

    2014-05-01

    In recent years, the frequency of catastrophes induced by natural hazard has increased and flood events in particular have been recognized as one of the most threatening water-related disasters. Severe floods have occurred in Europe over the last decade causing loss of life, displacement of people and heavy economic losses. Flood disasters are growing as a consequence of many factors both climatic and non-climatic. Indeed, the current increase of water-related disasters can be mainly attributed to the increase of exposure (elements potentially at risk in floodplains area) and vulnerability (i.e. economic, social, geographic, cultural, and physical/environmental characteristics of the exposure). Besides these factors, the strong effect of climate change is projected to radically modify the usual pattern of the hydrological cycle by intensifying the frequency and severity of flood events both at local, regional and global scale. Within this context, it is necessary to develop effective and pro-active strategies, tools and actions which allow to assess and (possibly) to reduce the risk of floods. In light of the recent European Flood Directive (FD), the KULTURisk-FP7 Project developed a state-of-the-art Regional Risk Assessment (RRA) methodology for assessing the risk imposed by floods events. The KULTURisk RRA methodology is based on the concept of risk being function of hazard, exposure and vulnerability. It is a flexible that can be adapted to different case studies (i.e. large rivers, alpine/mountain catchments, urban areas and coastal areas) and spatial scales (i.e. from the large river to the urban scale) that integrates the outputs of various hydrodynamics models (hazard) with sito-specific geophysical and socio-economic indicators (exposure and vulnerability factors such as land cover, slope, soil permeability, population density, economic activities, etc.). The main outputs of the methodology are GIS-based risk maps that identify and prioritize relative hot

  4. Dynamics of Bottomland Geomorphology and Vegetation Along a Dammed, Arid Region River: Implications for Streamflow Management

    Science.gov (United States)

    Shafroth, P. B.; House, P. K.

    2007-05-01

    In arid and semiarid western North America, floodplain forests dominated by native cottonwood and willow trees are highly valued as wildlife habitat and preferred recreation sites and are thus the focus of conservation efforts. The Bill Williams River harbors some of the most extensive native floodplain forests in the lower Colorado River region. Our work is aimed at understanding the dynamics of the Bill Williams River floodplain forests, in the context of pre- and post-dam hydrology and geomorphology. We have mapped bottomland geomorphology and vegetation using seven sets of orthorectified aerial photographs spanning more than 50 years. Two sets of photos (1953 and 1964) pre-date the completion of Alamo Dam, a large flood control structure; and three sets of photos (1996, 2002, and 2005) are from an era during which streamflow downstream of the dam has been managed to promote the establishment and survival of native floodplain forest. Comparison of the aerial photographs to LiDAR data collected in 2005 is providing a framework for quantifying changes in valley bottom morphology and estimating reach-scale changes in volumes of stored and evacuated sediment between 1953 and 2005. Furthermore, comparison of the extent of pre-dam active channel in 1953 with the extent of floodwaters from a regulated moderate flood in 2005 provides an approximation of the predominant patterns of aggradation and degradation in the system over this interval of time. Flood magnitude on the Bill Williams has been dramatically reduced since the closure of Alamo Dam in 1968, and low flows have increased considerably since 1979. Channels along the Bill Williams R. narrowed an average of 111 m (71 %) between 1953 and 1987, with most narrowing occurring after dam closure. Multiple regression analysis revealed significant relationships among flood power, summer flows, intermittency (independent variables) and channel width (dependent variable). Concurrent with channel narrowing was an expansion

  5. Submuscular transposition for the ulnar nerve at the elbow.

    Science.gov (United States)

    Posner, M A

    1984-01-01

    Forty patients who underwent submuscular transpositions of the ulnar nerve at the elbow (41 operations) were evaluated. A grading system was formulated to compare the preoperative and postoperative condition of each patient with respect to tenderness over the nerve, numbness, paresthesia, and muscle weakness. Thirty-seven of the 41 cases showed an improvement in grade. Of the 34 cases that demonstrated muscle weakness preoperatively, 25 improved following surgery, including five patients who had severe intrinsic muscle weakness with clawing of the ring and little finger. Muscle reattachment following nerve transposition was secure, even in a professional athlete.

  6. Surgery for transposition of great arteries: A historical perspective

    Directory of Open Access Journals (Sweden)

    Supreet P Marathe

    2015-01-01

    Full Text Available The history of surgery for transposition of great arteries (TGA has paralleled the history of cardiac surgery. In fact, it began before the birth of open heart surgery when the palliative Blalock-Hanlon septectomy was first performed in 1948. The atrial switch, which was an attempt to correct the physiology of transposition, had significant shortcomings. The arterial switch sought to address them. This has emerged as an anatomically as well as physiologically appropriate solution. Today we continue to pursue technical refinements as well as try to expand the indications of the arterial switch. This review traces the various milestones in this perpetual journey.

  7. Response of water budget to recent climatic changes in the source region of the Yellow River

    Science.gov (United States)

    Zhou, D.; Huang, R.

    2012-04-01

    The variation of surface water budget in the source region of the Yellow River is investigated. It is found that the spatial pattern of precipitation change is an important factor except precipitation amount itself and its intensity to determine the response of runoff change to precipitation change. Discharge in the source region had a significant decline after 1990; precipitation was low in the 1990s and in agreement with runoff, but it returned above normal after 2002 for more increase occurred in the dry area. The source region was experiencing rapid changes including decadal warming, wetting and wind speed decaying in recent decades. Surface water budget at the CMA stations within and surrounding the source region was simulated during 1960-2006 with an improved land surface model. The results indicated that evaporation was mainly limited by water availability in the dry area and thus most of precipitation increase was evaporated. By contrast, energy availability was a more important factor to determine evaporation in the wet area, and therefore, more evaporation occurred due to rapid warming although precipitation amount partly decreased, which contributed to the decrease of runoff generation after 2002. This mechanism controlling evaporation and its response together with the changed spatial pattern of precipitation led to water budget unfavorable for runoff generation in the source region during recent years.

  8. Groundwater Discharge and Salinity Sources to an Impaired Major River in a Semi-Arid Coastal Region: Nueces River, Texas

    Science.gov (United States)

    Murgulet, V.; Murgulet, D.; Hay, R.

    2015-12-01

    Nueces River, an impaired stream located on the South Texas Gulf coast area, has shown water quality degradation due to to increased salinity levels in areas adjacent to the Calallen saltwater reservoir dam. This study investigates the role of submarine groundwater discharge in delivering increased salt contents to the river and how the subsurface hydrology is affected by the presence of a salt barrier (i.e. saltwater dam) which separates the tidal and non-tidal parts of the Nueces river basin. Thus, a combination of resistivity profiling and elemental and stable isotope geochemistry methods has been applied to portions of the river located downstream (tidal) and upstream (non-tidal) of the dam. Preliminary data show that salinity levels gradually increases at the river bank indicating that groundwater is likely a source of solutes to the river in the upper, non-tidal portion. The presence of vertical upwelling of conductive groundwater plumes is also revealed by marine resistivity profiles collected along the river. Different sampling during the spring and summer of 2014 show higher concentration values of major ions (i.e., calcium, magnesium, sodium, potassium, chloride, etc.) and salinity of pore water for the upstream river at several locations while it remains relatively constant for bottom- and surface water. In addition, because the groundwater and porewater have slightly lower pH values, a shift to more acidic surface water accompanied by some increases in dissolved major ion concentrations and salinity suggest that groundwater might represent a source of increased salt content in the upper portion of the river. On the other hand, downstream dissolved major ion concentrations generally decrease in pore- and bottom water from spring to summer and are correlated with decreases in salinity while surface water becomes more saline with an increase in major ions. Therefore, these preliminary data indicate different hydrology systems of the two portions of the

  9. Impacts of Climate Change on Surface Hydrology in the Source Region of the Yellow River

    Science.gov (United States)

    Yuan, F.; Zhang, L.; Berndtsson, R.

    2015-12-01

    The source region of the Yellow River contributes about 35% of the total water yield in the Yellow River basin playing an important role for meeting the downstream water resources requirements. Hydroclimatic trend and periodicity during the last 50 years were investigated to identify significant changes in time and space over the study area. Results showed that mean annual temperature increased for all stations and it had an accelerated increasing trend during the last decade. Mean annual precipitation trends varied depending on station location; however, they were generally slightly decreasing. Annual streamflow decreased markedly especially from the 1990s but showed recovery during recent years. Statistically significant changes in trend occurred for temperature in 1998 and for streamflow in 1990. Based on the streamflow change point, seasonal analysis results showed that precipitation mainly decreased during the summer monsoon period (July-September) and temperature increased throughout the year. Corresponding to the weakened monsoon period the average runoff depth is decreasing by 0.74 mm/year over the whole area. Statistically significant 2 to 4-year periodicities for mean areal precipitation and temperature occurred over the area. For streamflow, an even stronger 8-year periodicity was revealed from the end of the 60s to the beginning of the 90s. Summer precipitation trends and teleconnections with global sea surface temperature (SST) and Southern Oscillation Index (SOI) from 1961 to 2010 were investigated. The summer precipitation in the whole region shows statistically significant negative correlations with the central Pacific SST for 0-4 month lags and with the southern Indian and Atlantic Ocean SST for 5-8 month lags. Analyses of sub-regions reveal intricate and complex correlations with different SST areas that further explain the summer precipitation variability. The SOI had significant positive correlations mainly for 0-2 month lag with summer

  10. Climatic variability of river outflow in the Pantanal region and the influence of sea surface temperature

    Science.gov (United States)

    Silva, Carlos Batista; Silva, Maria Elisa Siqueira; Ambrizzi, Tércio

    2016-03-01

    This paper investigates possible linear relationships between climate, hydrology, and oceanic surface variability in the Pantanal region (in South America's central area), over interannual and interdecadal time ranges. In order to verify the mentioned relations, lagged correlation analysis and linear adjustment between river discharge at the Pantanal region and sea surface temperature were used. Composite analysis for atmospheric fields, air humidity flux divergence, and atmospheric circulation at low and high levels, for the period between 1970 and 2003, was analyzed. Results suggest that the river discharge in the Pantanal region is linearly associated with interdecadal and interannual oscillations in the Pacific and Atlantic oceans, making them good predictors to continental hydrological variables. Considering oceanic areas, 51 % of the annual discharge in the Pantanal region can be linearly explained by mean sea surface temperature (SST) in the Subtropical North Pacific, Tropical North Pacific, Extratropical South Pacific, and Extratropical North Atlantic over the period. Considering a forecast approach in seasonal scale, 66 % of the monthly discharge variance in Pantanal, 3 months ahead of SST, is explained by the oceanic variables, providing accuracy around 65 %. Annual discharge values in the Pantanal region are strongly related to the Pacific Decadal Oscillation (PDO) variability (with 52 % of linear correlation), making it possible to consider an interdecadal variability and a consequent subdivision of the whole period in three parts: 1st (1970-1977), 2nd (1978-1996), and 3rd (1997-2003) subperiods. The three subperiods coincide with distinct PDO phases: negative, positive, and negative, respectively. Convergence of humidity flux at low levels and the circulation pattern at high levels help to explain the drier and wetter subperiods. During the wetter 2nd subperiod, the air humidity convergence at low levels is much more evident than during the other two

  11. Climatic variability of river outflow in the Pantanal region and the influence of sea surface temperature

    Science.gov (United States)

    Silva, Carlos Batista; Silva, Maria Elisa Siqueira; Ambrizzi, Tércio

    2017-07-01

    This paper investigates possible linear relationships between climate, hydrology, and oceanic surface variability in the Pantanal region (in South America's central area), over interannual and interdecadal time ranges. In order to verify the mentioned relations, lagged correlation analysis and linear adjustment between river discharge at the Pantanal region and sea surface temperature were used. Composite analysis for atmospheric fields, air humidity flux divergence, and atmospheric circulation at low and high levels, for the period between 1970 and 2003, was analyzed. Results suggest that the river discharge in the Pantanal region is linearly associated with interdecadal and interannual oscillations in the Pacific and Atlantic oceans, making them good predictors to continental hydrological variables. Considering oceanic areas, 51 % of the annual discharge in the Pantanal region can be linearly explained by mean sea surface temperature (SST) in the Subtropical North Pacific, Tropical North Pacific, Extratropical South Pacific, and Extratropical North Atlantic over the period. Considering a forecast approach in seasonal scale, 66 % of the monthly discharge variance in Pantanal, 3 months ahead of SST, is explained by the oceanic variables, providing accuracy around 65 %. Annual discharge values in the Pantanal region are strongly related to the Pacific Decadal Oscillation (PDO) variability (with 52 % of linear correlation), making it possible to consider an interdecadal variability and a consequent subdivision of the whole period in three parts: 1st (1970-1977), 2nd (1978-1996), and 3rd (1997-2003) subperiods. The three subperiods coincide with distinct PDO phases: negative, positive, and negative, respectively. Convergence of humidity flux at low levels and the circulation pattern at high levels help to explain the drier and wetter subperiods. During the wetter 2nd subperiod, the air humidity convergence at low levels is much more evident than during the other two

  12. Mitochondrial DNA evidence indicates the local origin of domestic pigs in the upstream region of the Yangtze River.

    Directory of Open Access Journals (Sweden)

    Long Jin

    Full Text Available Previous studies have indicated two main domestic pig dispersal routes in East Asia: one is from the Mekong region, through the upstream region of the Yangtze River (URYZ to the middle and upstream regions of the Yellow River, the other is from the middle and downstream regions of the Yangtze River to the downstream region of the Yellow River, and then to northeast China. The URYZ was regarded as a passageway of the former dispersal route; however, this assumption remains to be further investigated. We therefore analyzed the hypervariable segements of mitochondrial DNA from 513 individual pigs mainly from Sichuan and the Tibet highlands and 1,394 publicly available sequences from domestic pigs and wild boars across Asia. From the phylogenetic tree, most of the samples fell into a mixed group that was difficult to distinguish by breed or geography. The total network analysis showed that the URYZ pigs possessed a dominant position in haplogroup A and domestic pigs shared the same core haplotype with the local wild boars, suggesting that pigs in group A were most likely derived from the URYZ pool. In addition, a region-wise network analysis determined that URYZ contains 42 haplotypes of which 22 are unique indicating the high diversity in this region. In conclusion, our findings confirmed that pigs from the URYZ were domesticated in situ.

  13. Change of gene structure and function by non-homologous end-joining, homologous recombination, and transposition of DNA.

    OpenAIRE

    Wolfgang Goettel; Joachim Messing

    2009-01-01

    An important objective in genome research is to relate genome structure to gene function. Sequence comparisons among orthologous and paralogous genes and their allelic variants can reveal sequences of functional significance. Here, we describe a 379-kb region on chromosome 1 of maize that enables us to reconstruct chromosome breakage, transposition, non-homologous end-joining, and homologous recombination events. Such a high-density composition of various mechanisms in a small chromosomal int...

  14. Regional dynamics of persistent organic pollutants (POPs) in the Pearl River Delta, China: Implications and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Kai [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Zhang Baozhong [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li Shaomeng [Environment Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4 (Canada); Zeng, Eddy Y., E-mail: eddyzeng@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2011-10-15

    The mass transport budgets of 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (p,p'-DDT) and decabromodiphenyl ether (BDE-209) in the Pearl River Delta, South China were calculated based on previously collected data. Residual p,p'-DDT, mostly related to historical use, has largely settled into soil (780,000 kg), while the soil BDE-209 inventory (44,000 kg) is considerably smaller. Conversely, large amounts of BDE-209 currently used in numerous commercial products have resulted in a much higher atmospheric depositional flux of BDE-209 (28,100 kg/yr) relative to p,p'-DDT (310 kg/yr). The soil inventory of p,p'-DDT is predicted to decrease to half of its current value after 22 years, and the percent area containing soil p,p'-DDT at levels exceeding the effects range-medium (27 ng/g) will decrease from 40% to 20%. Finally, soil BDE-209 inventory will reach an equilibrium value of 940 tons in {approx}60 years, when BDE-209 levels in 50% of soil will be above an equivalent risk guideline value (125 ng/g). - Highlights: > Transport budgets of p,p'-DDT and BDE-209 in the Pearl River Delta were built. > Dry aerial deposition is the dominant route to transport p,p'-DDT and BDE-209. > Soil inventory of p,p'-DDT is much larger than that of BDE-209. > Soil inventory of p,p'-DDT would decline to half of its current value in 22 years. > Soil BDE-209 inventory is expected to reach an equilibrium value in {approx}60 years. - Regional dynamics of p,p'-DDT and BDE-209 in the Pearl River Delta (South China) are examined and used to predict temporal variances.

  15. Physico-Chemical Characteristics Of Water Of River Mandakini In Chitrakoot Region

    Directory of Open Access Journals (Sweden)

    I.P.Tripathi

    2014-10-01

    Full Text Available The river flows in Madhya Pradesh for about 25km, then makes a border of district Satna (Madhya Pradesh and district Chitrakoot (Uttar Pradesh for the next 25km and again enters in Madhya Pradesh just downstream of Sati Anusuiya. After flowing through about 15km more in M.P., it crosses into Uttar Pradesh near Ramghat in Chitrakoot area and later flows only in Uttar Pradesh finally it joins river Yamuna near Rajapur. The present research works identify Physico - Chemical Characteristics of water quality of River Mandakini in Chitrakoot Region. The water samples were analysed some parameter like pH, TDS, TSS, TH, Alkalinity, DO, BOD, COD, Nitrate, and Sulphate. The pH value was found between 7.49 to 8.5, TDS 290 to 470mg/l, TSS 140 to 192mg/l, TH 250 to 288mg/l, Alkalinity 175 to 198mg/l, DO 3.19 to 6.5mg/l, BOD 2.5 to 12 mg/l, COD 10 to 38mg/l, Nitrate 3 to 9mg/l, Sulphate 3 to 8mg/. Most of the sample BOD and COD are higher than the permissible limit prescribed by WHO (1994 as 6mg/l and 10mg/l respectively.TDS, TSS, TH, Alkalinity, Nitrate and Sulphate of all the results below the WHO recommended values as 500mg/l, 200mg/l, 300mg/l, 200mg/l, 45mg/l, 250mg/l.

  16. Geothermal investigations in Idaho. Part 8. Heat flow study of the Snake River Plain region, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Brott, C.A.; Blackwell, D.D.; Mitchell, J.C.

    1976-09-01

    The Snake River Plain of Idaho has recent lava flows and a large number of thermal springs and wells. A heat flow study was initiated which, together with available geological and geophysical information, allows a better definition of the geothermal resource and evaluation of the geothermal potential. Local geothermal anomalies were not the objects of this study and have not been studied in detail. The quality of the heat flow values obtained varies as interpretation was necessary to determine geothermal gradients for many of the holes which had disturbances. A major problem in determining the heat flow values is the lack of knowledge of the in situ porosity of the rocks. The heat flow values obtained for the Eastern Snake River Plain are from shallow wells (< 200 m), hence the heat flow there is low (< 0.5 HFU) because of the water movement in the Snake Plain aquifer. The anomalous regional heat flow pattern around the Snake River Plain, together with other geophysical and geological data, suggest the presence of a major crustal heat source. With the exception of the area of the Snake Plain aquifer, high geothermal gradients were found in all areas of southern Idaho (40 to 100/sup 0/C/km). Temperatures hot enough for space heating can be found most anywhere in the Plain at relatively shallow depths (1 to 2 km). Temperatures hot enough for electrical power generation (200/sup 0/C) can be found beneath southern Idaho almost anywhere at depths of 3 to 4 kilometers. The Plain is fault bounded and hot water circulating along the fault zones from depths can be a very important geothermal resource at shallow depths. The margins of the Plain have the highest heat flow values, are the most faulted, and have possibly the highest geothermal resource potential.

  17. Importance of NOx control for peak ozone reduction in the Pearl River Delta region

    Science.gov (United States)

    Li, Ying; Lau, Alexis K. H.; Fung, Jimmy C. H.; Zheng, Junyu; Liu, Shawchen

    2013-08-01

    As major air pollutants and key precursors of several secondary air pollutants, nitrogen oxide (NOx) emissions are regulated in many countries. However, NOx control increases ozone concentrations when the ozone formation regime is volatile organic compound (VOC) limited. Although many studies have shown that NOx regulation reduces ozone levels over the long term, it is still of concern that NOx regulation increases short-term ozone levels in metropolitan regions, where ozone formation is found to be predominantly VOC-limited. The Pearl River Delta (PRD) in China is such a region. Our modeling sensitivity study shows that while NOx reduction in the PRD region may raise the mean ozone concentration, it can also decrease peak ozone levels. Similar changes are observed in the NOx and ozone data of the PRD regional air quality monitoring network (2006-2012), lending further credence to our results. In the model, this NOx control effect is a result of the complicated spatial and diurnal variations of the ozone formation regime. In most of the PRD region, the formation regime is VOC-limited in the morning and becomes NOx-limited during peak ozone hours. Although some areas are always VOC-limited, their ozone concentrations are relatively low, and the ozone increases caused by NOx reduction generally do not cause higher ozone levels than the region's original ozone maxima. Several control scenarios are simulated to evaluate the effects of various possible control regulations. Our results show that in addition to VOC control, NOx control can be effective for reducing peak ozone concentrations in the PRD region.

  18. THE REGIONAL DEVELOPMENT IN THE PEARL RIVER DELTA IN NEW TERM

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Since China opening to outside world, the economy inthe Pearl(Zhujiang) River Delta(PRD) has been dou-ble digit growth. It has been known as one of mature fast growth areas in the world and become the model and hope of Chi-nese reform and opening to outside world. The regional development in PRD is the outcome of polarization effects. The polar-ization effects actually are extension of international regional division and a combination of Hongkong's influence and re-form and open-door policies on the mainland. Since the 1990s, driven by knowledge-based economy, the PRD has furtheradjusted the industrial structure and achieved good progress in upgrading industrial structure. Its high technology industryhas developed quickly and the economic internationalization has deepened, meanwhile, the region is going through transforma-tion and some new trends have begun to appear, which include: university towns springing up, industrial globalization andthe construction of Hi-tech development zones. The paper suggests that with the economic growth changing from relying onthe low level production elements to relying on high level production elements, the regional policies in GuangdongProvince should develop correspondingly: 1 ) make a plan to prohibite the blind construction in innovative spatial construc-tions; 2) make measures to attract the overseas talents to establish a pool of talent; 3) work out the favorable policies forabsorbing larger capital; 4) formulate the policy of attracting a cluster of industries to speed up the upgrade of industrialdevelopment.

  19. Impacts of urban and industrial development on Arctic land surface temperature in Lower Yenisei River Region.

    Science.gov (United States)

    Li, Z.; Shiklomanov, N. I.

    2015-12-01

    Urbanization and industrial development have significant impacts on arctic climate that in turn controls settlement patterns and socio-economic processes. In this study we have analyzed the anthropogenic influences on regional land surface temperature of Lower Yenisei River Region of the Russia Arctic. The study area covers two consecutive Landsat scenes and includes three major cities: Norilsk, Igarka and Dudingka. Norilsk industrial region is the largest producer of nickel and palladium in the world, and Igarka and Dudingka are important ports for shipping. We constructed a spatio-temporal interpolated temperature model by including 1km MODIS LST, field-measured climate, Modern Era Retrospective-analysis for Research and Applications (MERRA), DEM, Landsat NDVI and Landsat Land Cover. Those fore-mentioned spatial data have various resolution and coverage in both time and space. We analyzed their relationships and created a monthly spatio-temporal interpolated surface temperature model at 1km resolution from 1980 to 2010. The temperature model then was used to examine the characteristic seasonal LST signatures, related to several representative assemblages of Arctic urban and industrial infrastructure in order to quantify anthropogenic influence on regional surface temperature.

  20. Summary of the Snake River plain Regional Aquifer-System Analysis in Idaho and eastern Oregon

    Science.gov (United States)

    Lindholm, G.F.

    1996-01-01

    Regional aquifers underlying the 15,600-square-mile Snake River Plain in southern Idaho and eastern Oregon was studied as part of the U.S. Geological Survey's Regional Aquifer-System Analysis program. The largest and most productive aquifers in the Snake River Plain are composed of Quaternary basalt of the Snake River Group, which underlies most of the 10,8000-square-mile eastern plain. Aquifer tests and simulation indicate that transmissivity of the upper 200 feet of the basalt aquifer in the eastern plain commonly ranges from about 100,000 to 1,000,000 feet squared per day. However, transmissivity of the total aquifer thickness may be as much as 10 million feet squared per day. Specific yield of the upper 200 feet of the aquifer ranges from about 0.01 to 0.20. Average horizontal hydraulic conductivity of the upper 200 feet of the basalt aquifer ranges from less than 100 to 9,000 feet per day. Values may be one to several orders of magnitude higher in parts in individual flows, such as flow tops. Vertical hydraulic conductivity is probably several orders of magnitude lower than horizontal hydraulic conductivity and is generally related to the number of joints. Pillow lava in ancestral Snake River channels has the highest hydraulic conductivity of all rock types. Hydraulic conductivity of the basalt decreases with depth because of secondary filling of voids with calcite and silica. An estimated 80 to 120 million acre-feet of water is believed to be stored in the upper 200 feet of the basalt aquifer in the eastern plain. The most productive aquifers in the 4,800-square-mile western plain are alluvial sand and gravel in the Boise River valley. Although aquifer tests indicate that transmissivity of alluvium in the Boise River valley ranges from 5,000 to 160,000 feet squared per day, simulation suggests that average transmissivity of the upper 500 feet is generally less than 20,000 feet squared per day. Vertically averaged horizontal hydraulic conductivity of the upper

  1. Evaluation of a regional climate model for atmospheric simulation over Arctic river basins

    Institute of Scientific and Technical Information of China (English)

    MA Yan; CHEN Shang; HUA Feng; WEI Helin; D. H. BROMWICH

    2008-01-01

    Evaluation on a regional climate model was made with five-month atmospheric simulations over the Arctic river basins. The simulations were performed with a modified mesoscale model, Polar MM5 coupled to the NCAR Land Surface Model (LSM) to illustrate the skill of the coupled model (Polar MM5+LSM) in simulating atmospheric circulation over the Arctic river basins. Near-surface and upper-air observations were used to verify the simulations. Sensitivity studies between the Polar MM5 and Polar MMS+LSM simulations revealed that the coupled model could improve the forecast skill for surface variables at some sites. In addition, the extended evaluations of the coupled model simulations on the North American Arctic domain during December 15, 2002 to May 15, 2003 were carded out. The time series plots and statistics of the observations and Polar MM5+LSM simulations at six stations for near-surface and vertical profiles at 850 hPa and 500 hPa were analyzed. The model was found capable of reproducing the observed atmospheric behavior in both magnitude and variability, especially for temperature and near-surface wind direction.

  2. Coping with EU Environmental Legislation : Transposition Principles and Practices

    NARCIS (Netherlands)

    Anker, Helle Tegner; de Graaf, K.J.; Purdy, Ray; Squintani, Lorenzo

    2015-01-01

    A ‘burden reducing’ agenda has spurred an increased interest in how EU environmental legislation is transposed into national legislation—most prominently reflected in the principle of ‘no gold-plating’. Yet, an important question is to what extent transposition principles and practices may ensure a

  3. Relational Learning in a Context of Transposition: A Review

    Science.gov (United States)

    Lazareva, Olga F.

    2012-01-01

    In a typical transposition task, an animal is presented with a single pair of stimuli (for example, S3+S4-, where plus and minus denote reward and nonreward and digits denote stimulus location on a sensory dimension such as size). Subsequently, an animal is presented with a testing pair that contains a previously reinforced or nonreinforced…

  4. Coping with EU Environmental Legislation : Transposition Principles and Practices

    NARCIS (Netherlands)

    Anker, Helle Tegner; de Graaf, K.J.; Purdy, Ray; Squintani, Lorenzo

    2015-01-01

    A ‘burden reducing’ agenda has spurred an increased interest in how EU environmental legislation is transposed into national legislation—most prominently reflected in the principle of ‘no gold-plating’. Yet, an important question is to what extent transposition principles and practices may ensure a

  5. Method and structure for cache aware transposition via rectangular subsections

    Science.gov (United States)

    Gustavson, Fred Gehrung; Gunnels, John A

    2014-02-04

    A method and structure for transposing a rectangular matrix A in a computer includes subdividing the rectangular matrix A into one or more square submatrices and executing an in-place transposition for each of the square submatrices A.sub.ij.

  6. [Prosthesis interposition in the case of subclavian artery transposition].

    Science.gov (United States)

    György, G; Acosta Alvarez, P

    1993-01-01

    When we can't realize the reimplantation because of technical difficulties, special cases are presented during transposition from the subclavian artery to the primitive carotid artery. In these cases, between primitive carotid artery and the subclavian artery and also the vertebral artery, Gore-tex's tubes were implanted with favourable results.

  7. Assessment of Spatial Distribution and Submerged Scope for Storm Surge in the Pearl River Delta Region

    Institute of Scientific and Technical Information of China (English)

    LI Kuo; LI Guo-sheng

    2011-01-01

    The aim of this study was to explore the spatial distribution and submerged scope for storm surge in the Pearl River Delta (PRD) region.Based on the data of storm surges in the PRD region in the past 30 years, the return periods of 12 tide-gauge stations for storm surges were calculated separately with the methods of Gumbel and Pearson-iii.The data of another six tide-gauge stations in Guangdong Coast was quoted to depict the overall features of storm surges in Guangdong.Using least-square method, the spatial distribution models of storm surges in different retum periods were established to reveal the distribution rule of the set-up values of storm surges.The spatial distribution curves of storm surges in different retum periods in the PRD Region were drawn up based on the models and the terrain of Guangdong Coast.According to the curves, the extreme set-up values of storm surges in 1 000,100, 10 a return periods were determined on each spot of Guangdong Coast.Applying the spatial analysis technology of ArcGIS, with the topography data of the PRD Region, the submerged scopes of flood caused by storm surge in 1 000, 100, 10 a return periods were drawn up.The loss caused by storm surges was estimated.Results showed that the storm surges and the topography of PRD region jointly led to the serious flood in the PRD region.This assessment would be useful for the planning and design department to make decision and provide government scientific basis for storm surge prediction, coastal engineering designing and the prevention of storm surge disaster.

  8. Science-policy interplay: Air quality management in the Pearl River Delta region and Hong Kong

    Science.gov (United States)

    Zhong, Liuju; Louie, Peter K. K.; Zheng, Junyu; Yuan, Zibing; Yue, Dingli; Ho, Josephine W. K.; Lau, Alexis K. H.

    2013-09-01

    The information provided by the scientific studies and control measures implemented in the Pearl River Delta (PRD) region of China reveals that tremendous progress has been made in the understanding of regional air pollution issues and the deployment of mitigation measures for alleviating these problems. Given the unparalleled rapid economic growth in the PRD over the past two decades, such progress was only made possible by strong, science-based support and the partnerships between government and research institutions in the region and overseas. Researchers from these partnership programs and related studies have deployed cutting-edge expertise and experience in various crucial mainland China and mainland China/Hong Kong-level projects. China recognizes the importance of protecting the environment and cleaning up the air in the pursuit of sustainable growth and economic development. To avoid falling into a cycle of event-driven clean-up efforts, China has recently taken a major step and updated the national ambient air quality standards. Clearly, China is implementing an increasing number of evidence-based policies to address air pollution problems. Thus, to bring a fresh impetus at a national level, the PRD must maintain and augment the Hong Kong-mainland collaborative momentum, inducing a "whole-China" effort to clean up air pollution. To strengthen the science-based support system and ensure continuous and concerted effort in implementing the regional multi-pollutant control strategy, there must be an overarching and integral Hong Kong-Guangdong science consortium framework supporting the formulation of regional policy and control measures built on common goals under the "one country, two systems" principle. The "PRD Approach" of the air quality management regime reflected regional cooperative efforts in synchronous air pollutant control, catalyzed the crucial role of information disclosure and subtly transformed the air quality management approach to overcome

  9. Engaging the Dan River Region to reduce obesity: application of the Comprehensive Participatory Planning and Evaluation process.

    Science.gov (United States)

    Zoellner, Jamie; Motley, Monica; Wilkinson, Margie E; Jackman, Barbara; Barlow, Morgan L; Hill, Jennie L

    2012-01-01

    Despite ongoing recommendations to engage health-disparate populations in the initiation and execution of community-based research, few studies report on the process of community engagement. The action-oriented Comprehensive Participatory Planning and Evaluation (CPPE) process is designed to guide community health planning and evaluation. This article describes how the CPPE process was utilized within a community-based participatory research initiative aimed at addressing obesity in the health-disparate Dan River Region. Encouraging community engagement in formulating research agendas and promoting ownership of health solutions will be key to improving obesity risk factors among Dan River Region residents and similar vulnerable communities.

  10. Soil and plant responses to degradation of alpine grassland in source region of the Yellow River

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Land degradation has been rapidly taking place in source region of the Yellow River in China. This study was conducted during 2008 in Maduo County to investigate soil and plant changes in relation to land degradation. Several results were derived from this work. First, the soil organic carbon (SOC) and total nitrogen (TN) decreased significantly on the extremely degraded land comparing with the natural grassland. Second, soil bulk density increased as land degradation worsened. Soil bulk density of the extremely degraded land was significantly greater than that of the grassland. Third, pH showed no obvious variation pattern. Finally, aboveground biomass decreased from grassland to the moderately degraded land. But aboveground biomass increased on the extremely degraded land and very extremely degraded land with most aboveground biomass inedible for livestock.

  11. Nutritional Taboos among the Fullas in Upper River Region, The Gambia

    Directory of Open Access Journals (Sweden)

    Guillermo Martínez Pérez

    2013-01-01

    Full Text Available Malnutrition is one of the leading causes of morbidity and mortality of children in the world. In The Gambia, malnutrition is one of the major public health problems. Among the factors determining its high prevalence, cultural norms play a crucial role. Food taboos influence the amount, frequency, and quality of nutrients that mothers and children consume. In this qualitative study carried out in the Upper River Region, The Gambia, seventeen mothers whose ethnic affiliation is Fulla were interviewed. The objective was to describe their food taboos and how they influence their nutritional health. The findings of this study demonstrate that some of the taboos practiced by the Fulla may be regarded as contributing factors to protein-energy malnutrition in children and pregnant and lactating women. The findings will inform the design of future health education strategies targeting malnutrition in this specific cultural context.

  12. The Seine system: introduction to a multidisciplinary approach of the functioning of a regional river system.

    Science.gov (United States)

    Billen, Gilles; Garnier, Josette; Mouchel, Jean-Marie; Silvestre, Marie

    2007-04-01

    The Seine basin (France) is dominated by the megalopolis of Paris (10 millions inhabitants), surrounded by intensive agricultural areas: it represents an important example of regional territory strongly affected by anthropogenic activity. In the scope of the PIREN-Seine program, an interdisciplinary study of this basin was conducted. This paper introduces a special issue of the Science of the Total Environment devoted to the results of this program. It summarizes the main features of the Seine river system, the physical characteristics of its drainage network and its watershed, and the nature and spatial distribution of human activities. The scientific approaches used for the study of the system are described, emphasizing the role of material budgeting, mathematical modeling and historical reconstruction. Some functional characteristics of the Seine watershed and drainage network are summarized, showing that the system is now essentially controlled by anthropogenic constraints.

  13. Practical possibility to manage radiation pollution on the examples of the region of Krivoy Rog and Loire river

    Energy Technology Data Exchange (ETDEWEB)

    Sizonenko, V. [Institute of General Energy of NAS of Ukraine (Ukraine)

    2014-07-01

    Uranium deposit placed near-by Zoltje Vody City in the region of Krivoy Rog is one of most on territory of Ukraine. One of main mining objects of the city is a mine 'Nova', which works mine of ferrous and uranium ores. Mine water which is pumped out on a surface is saturated by uranium is used for the technological necessities of mining complex and finally is thrown down in a Zoltaja River. This results in contamination of waters of Ingulets River (tributary of the Dnieper River) and Karachunovskoe reservoir - of the basic source of water-supply of whole region. The paper will show possibilities for managing of possible consequences of accidental events of volley inflow of the muddy mine waters in Zoltaja River, prognostication of possible consequences of such catastrophic situations. The computer model of the water system of region Zoltje Vody City - Krivoy Rog City has been developed with usage of the new box model of incomplete inter-fusion with lagging argument. It gave the opportunity for accurate prognostication and short time of preparedness. Examples of prognostication of levels of concentrations of radionuclide ({sup 238}U) in waters of the Ingulets River, Zoltaja River and Karachunovskoe reservoir depending on the discharges of water of rivers and modes (regulation and catastrophic) of polluted water kick of mine 'Nova' are demonstrated. Possibilities of water protection actions are explored at the catastrophic discharge of mine water to Zoltaja River. Protection action is dilution by waters from the storage pool of Ingulets River. Such measures in many cases enable to access to safe and adequate water and sanitation services during the catastrophic events. The practical efforts for mitigation of consequences of the protracted catastrophic manmade influence on a water environment and possibilities of rehabilitation of the water system in the whole region of Krivoy Rog were analyzed in the work. The research of emissions tritium in the

  14. Regional groundwater flow and geochemical evolution in the Amacuzac River Basin, Mexico

    Science.gov (United States)

    Morales-Casique, Eric; Guinzberg-Belmont, Jacobo; Ortega-Guerrero, Adrián

    2016-11-01

    An approach is presented to investigate the regional evolution of groundwater in the basin of the Amacuzac River in Central Mexico. The approach is based on groundwater flow cross-sectional modeling in combination with major ion chemistry and geochemical modeling, complemented with principal component and cluster analyses. The hydrogeologic units composing the basin, which combine aquifers and aquitards both in granular, fractured and karstic rocks, were represented in sections parallel to the regional groundwater flow. Steady-state cross-section numerical simulations aided in the conceptualization of the groundwater flow system through the basin and permitted estimation of bulk hydraulic conductivity values, recharge rates and residence times. Forty-five water locations (springs, groundwater wells and rivers) were sampled throughout the basin for chemical analysis of major ions. The modeled gravity-driven groundwater flow system satisfactorily reproduced field observations, whereas the main geochemical processes of groundwater in the basin are associated to the order and reactions in which the igneous and sedimentary rocks are encountered along the groundwater flow. Recharge water in the volcanic and volcano-sedimentary aquifers increases the concentration of HCO3 -, Mg2+ and Ca2+ from dissolution of plagioclase and olivine. Deeper groundwater flow encounters carbonate rocks, under closed CO2 conditions, and dissolves calcite and dolomite. When groundwater encounters gypsum lenses in the shallow Balsas Group or the deeper Huitzuco anhydrite, gypsum dissolution produces proportional increased concentration of Ca2+ and SO4 2-; two samples reflected the influence of hydrothermal fluids and probably halite dissolution. These geochemical trends are consistent with the principal component and cluster analyses.

  15. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG; ManSing; NICHOL; Janet; LEE; Kwon; Ho

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolution images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta region. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the determination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflectance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r = 0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  16. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG ManSing; NICHOL Janet; LEE Kwon Ho; LI ZhanQing

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolu-tion images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta re-gion. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the deter-mination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflec-tance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r=0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  17. Public health and medical care for the world's factory: China's Pearl River Delta Region

    Directory of Open Access Journals (Sweden)

    Rodwin Victor G

    2011-10-01

    Full Text Available Abstract While the growth of urbanization, worldwide, has improved the lives of migrants from the hinterland, it also raises health risks related to population density, concentrated poverty and the transmission of infectious disease. Will megacity regions evolve into socially infected breeding grounds for the rapid transmission of disease, or can they become critical spatial entities for the protection and promotion of population health? We address this question for the Pearl River Delta Region (PRD based on recent data from Chinese sources, and on the experience of how New York, Greater London, Tokyo and Paris have grappled with the challenges of protecting population health and providing their populations with access to health care services. In some respects, there are some important lessons from comparative experience for PRD, notably the importance of covering the entire population for health care services and targeting special programs for those at highest risk for disease. In other respects, PRD's growth rate and sheer scale make it a unique megacity region that already faces new challenges and will require new solutions.

  18. A radon and meteorological measurement network for the Alligator Rivers Region, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P. E-mail: paul.martin@deh.gov.au; Tims, S. E-mail: steve.tims@anu.edu.au; Ryan, B. E-mail: bruce.ryan@ea.gov.au; Bollhoefer, A. E-mail: andreas.bollhoefer@ea.gov.au

    2004-07-01

    The network described in this paper has been set up to provide detailed time-series data on concentrations of {sup 222}Rn in air at various locations within the Alligator Rivers Region, over a time frame of several years. These data will be important in assessing the effects of uranium mining operations on radon levels in the region, both in providing baseline and monitoring data and in calibrating and verifying predictive models. At present, three stations are operating in the region with a fourth being commissioned. Each station logs half hourly average radon concentrations and relevant meteorological data (wind speed, direction and variability, air pressure and temperature, relative humidity, soil temperature, rain and sunshine rates). It is intended to operate the four stations at selected locations for one- or two-year intervals, at the end of which three will be moved to new locations (one station at Mudginberri will be kept as a constant control station). Sites for which extensive datasets are currently available include: Jabiru Town, Jabiru East, Djarr Djarr, East Alligator Ranger Station and Nabarlek minesite. Illustrative data from these sites are presented.

  19. Source apportionment and health effect of NOx over the Pearl River Delta region in southern China.

    Science.gov (United States)

    Lu, Xingcheng; Yao, Teng; Li, Ying; Fung, Jimmy C H; Lau, Alexis K H

    2016-05-01

    As one of the most notorious atmospheric pollutants, NOx not only promotes the formation of ozone but also has adverse health effects on humans. It is therefore of great importance to study the sources of NOx and its effects on human health. The Comprehensive Air Quality Model (CAMx) modeling system and ozone source apportionment technology (OSAT) were used to study the contribution of NOx from different emission sources over southern China. The results indicate that heavy duty diesel vehicles (HDDVs) and industrial point sources are the two major local NOx sources, accounting for 30.8% and 18.5% of local NOx sources, respectively. In Hong Kong, marine emissions contributed around 43.4% of local NOx in 2011. Regional transport is another important source of this pollutant, especially in February and November, and it can contribute over 30% of ambient NOx on average. Power plant point emission is an significant regional source in Zhuhai, Zhongshan and Foshan. The total emission sources are estimated to cause 2119 (0-4405) respiratory deaths and 991 (0-2281) lung cancer deaths due to long-term exposure to NOx in the Pearl River Delta region. Our results suggest that local governments should combine their efforts and vigorously promote further reduction of NOx emissions, especially for those sources that make a substantial contribution to NOx emissions and affect human health: HDDV, LDGV, industrial point sources and marine sources.

  20. The inhabited environment, infrastructure development and advanced urbanization in China’s Yangtze River Delta Region

    Science.gov (United States)

    Zhu, Xiaoqing; Gao, Weijun; Zhou, Nan; Kammen, Daniel M.; Wu, Yiqun; Zhang, Yao; Chen, Wei

    2016-12-01

    This paper analyzes the relationship among the inhabited environment, infrastructure development and environmental impacts in China’s heavily urbanized Yangtze River Delta region. Using primary human environment data for the period 2006-2014, we examine factors affecting the inhabited environment and infrastructure development: urban population, GDP, built-up area, energy consumption, waste emission, transportation, real estate and urban greenery. Then we empirically investigate the impact of advanced urbanization with consideration of cities’ differences. Results from this study show that the growth rate of the inhabited environment and infrastructure development is strongly influenced by regional development structure, functional orientations, traffic network and urban size and form. The effect of advanced urbanization is more significant in large and mid-size cities than huge and mega cities. Energy consumption, waste emission and real estate in large and mid-size cities developed at an unprecedented rate with the rapid increase of economy. However, urban development of huge and mega cities gradually tended to be saturated. The transition development in these cities improved the inhabited environment and ecological protection instead of the urban construction simply. To maintain a sustainable advanced urbanization process, policy implications included urban sprawl control polices, ecological development mechanisms and reforming the economic structure for huge and mega cities, and construct major cross-regional infrastructure, enhance the carrying capacity and improvement of energy efficiency and structure for large and mid-size cities.

  1. VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

    Science.gov (United States)

    Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

    2013-09-01

    Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

  2. Tree-ring-based reconstruction of streamflow for the Zaqu River in the Lancang River source region, China, over the past 419 years

    Science.gov (United States)

    Xiao, Dingmu; Shao, Xuemei; Qin, Ningsheng; Huang, Xiaomei

    2016-12-01

    Tree-ring width standard chronologies were created from juniperus przewalskii Kom data collected in the Lancang River Headwaters region. Statistical analysis results showed high correlation (r = 0.69) between the composite tree-ring chronology and instrumental streamflow records at the Xiangda Hydrological Station during the annual September-August interval. Streamflow of the Zaqu River in the Lancang river source region was reconstructed for the past 419 years. The model was stable and revealed 14 extremely dry years and 6 extremely wet years. The results showed relatively low streamflow periods occurred during 602-1614, 1633-1656, 1684-1697, 1712-1722, 1735-1753, 1817-1829, 1847-1861, 1874-1884, 1946-1959, 1961-1977, and 1990-2000. Relatively high streamflow periods occurred during 1615-1630, 1657-1678, 1698-1711, 1754-1783, 1803-1813, 1830-1840, 1862-1873, 1892-1909, and 1932-1945. Comparison with tree-ring based streamflow reconstructions and chronologies from surrounding areas provided a high degree of confidence in our reconstruction. The empirical mode decomposition analysis suggests the existence of significant periods with intervals of 2-4, 5-9, 11-16, and 26-50 years. Regional comparison indicated that our reconstruction was associated with large-scale atmospheric-oceanic variability, such as the El Niño-Southern Oscillation (ENSO), Atlantic Multidecadal Oscillation (AMO) index, Pacific Decadal Oscillation (PDO) index, and East Asian monsoon variation. This research provides a useful foundation for water resource planning and management guidance in the Three-River Headwaters Region.

  3. Tree-ring-based reconstruction of streamflow for the Zaqu River in the Lancang River source region, China, over the past 419 years

    Science.gov (United States)

    Xiao, Dingmu; Shao, Xuemei; Qin, Ningsheng; Huang, Xiaomei

    2017-07-01

    Tree-ring width standard chronologies were created from juniperus przewalskii Kom data collected in the Lancang River Headwaters region. Statistical analysis results showed high correlation ( r = 0.69) between the composite tree-ring chronology and instrumental streamflow records at the Xiangda Hydrological Station during the annual September-August interval. Streamflow of the Zaqu River in the Lancang river source region was reconstructed for the past 419 years. The model was stable and revealed 14 extremely dry years and 6 extremely wet years. The results showed relatively low streamflow periods occurred during 602-1614, 1633-1656, 1684-1697, 1712-1722, 1735-1753, 1817-1829, 1847-1861, 1874-1884, 1946-1959, 1961-1977, and 1990-2000. Relatively high streamflow periods occurred during 1615-1630, 1657-1678, 1698-1711, 1754-1783, 1803-1813, 1830-1840, 1862-1873, 1892-1909, and 1932-1945. Comparison with tree-ring based streamflow reconstructions and chronologies from surrounding areas provided a high degree of confidence in our reconstruction. The empirical mode decomposition analysis suggests the existence of significant periods with intervals of 2-4, 5-9, 11-16, and 26-50 years. Regional comparison indicated that our reconstruction was associated with large-scale atmospheric-oceanic variability, such as the El Niño-Southern Oscillation (ENSO), Atlantic Multidecadal Oscillation (AMO) index, Pacific Decadal Oscillation (PDO) index, and East Asian monsoon variation. This research provides a useful foundation for water resource planning and management guidance in the Three-River Headwaters Region.

  4. [Distribution of Regional Pollution and the Characteristics of Vertical Wind Field in the Pearl River Delta].

    Science.gov (United States)

    Liu, Jian; Wu, Dui; Fan, Shao-jia

    2015-11-01

    Based on the data of hourly PM2.5 concentration of 56 environmental monitoring stations and 9 cities over the Pearl River Delta (PRD) region, the distributions of PM2.5 pollution in PRD region were analyzed by systematic cluster analysis and correlational analysis. It was found that the regional pollution could be divided into 3 types. The first type was the pollution occurred in Dongguan, Guangzhou, Foshan and Jiangmen (I type), and the second type was the pollution occurred in Zhongshan, Zhuhai, Shenzhen and Huizhou (II type), while the last type was the pollution only occurred in Zhaoqing (III type). During the study period, they occurred 47, 7 and 128 days, respectively. During events of pollution type I, except Zhuhai, Shenzhen and Huizhou, the PM2.5 concentrations of other cities were generally high, while the PM2.5 concentration in whole PRD region was over 50.0 μg x m(-3) during events of pollution type II. The regions with higher PM2.5 concentration was mainly concentrated in Zhaoqing, Guangzhou and Foshan during events of pollution type III. The wind data from 4 wind profile radars located in PRD region was used to study the characteristics of vertical wind field of these 3 pollution types. It was found that the wind profiles of type I and III were similar that low layer and high layer were controlled by the southeast wind and the southwest wind, respectively. For type II, the low layer and high layer were influenced by northerly wind and westerly wind, respectively. Compared with other types, the wind speed and ventilation index of type II. were much higher, and the variation of wind direction at lower-middle-layer was much smaller. When PRD region was influenced by northerly winds, the PM2.5 concentration in the entire PRD region was higher. When PRD region was controlled by southeast wind, the PM2.5 concentrations of I and II areas were relatively lower, while the pollution in III area was relatively heavier.

  5. Black carbon measurements in the Pearl River Delta region of China

    Science.gov (United States)

    Huang, X.; Gao, R.; Schwarz, J. P.; Ling-Yan, H.; Fahey, D. W.; Laurel A, W.; Zeng, L.

    2009-12-01

    The Pearl River Delta (PRD) region in southeastern China is one of the most polluted industrial/metropolitan areas in the world. The 3C-STAR campaign (Synthesized Prevention Techniques for Air Pollution Complex and Integrated Demonstration in Key City-Cluster Region), carried out in October-November, 2008, was aimed at improving the understanding and quantification of air pollution in the region, while developing technical capacity for regional air quality monitoring and modeling. We report single-particle soot photometer (SP2) measurements and analyses of refractory black carbon (rBC) at Kaiping, a rural site downwind of the major pollution sources in the PRD area. The rBC mass loadings varied between 0.5 and 10 µg-rBC kg-air-1, and averaged 2.8 µg-rBC kg-air-1. These values are roughly an order of magnitude higher than those measured in the Houston, Texas, a major US metropolitan area. The rBC mass distributions show a primary lognormal peak with a median mass diameter of 0.22 µm volume-equivalent diameter (VED), which is similar to those observed in Houston and other regions with the SP2 instrument. A second mode with a mass median diameter of 0.69 µm VED, has not been observed before. Coatings are found on over 50% of rBC particles, suggesting that they are aged and/or of biomass-burning origin. The high rBC loadings cause significant heating of the atmosphere due to direct solar absorption. A diurnal heating rate of over 0.5 K day-1. is estimated for the average of entire dataset with a maximum heating rate near 3 K day-1.

  6. Dynamic reconstruction of eye closure by muscle transposition or functional muscle transplantation in facial palsy.

    Science.gov (United States)

    Frey, Manfred; Giovanoli, Pietro; Tzou, Chieh-Han John; Kropf, Nina; Friedl, Susanne

    2004-09-15

    For patients with facial palsy, lagophthalmus is often a more serious problem than the inability to smile. Dynamic reconstruction of eye closure by muscle transposition or by free functional muscle transplantation offers a good solution for regaining near-normal eye protection without the need for implants. This is the first quantitative study of three-dimensional preoperative and postoperative lid movements in patients treated for facial paralysis. Between February of 1998 and April of 2002, 44 patients were treated for facial palsy, including reconstruction of eye closure. Temporalis muscle transposition to the eye was used in 34 cases, and a regionally differentiated part of a free gracilis muscle transplant after double cross-face nerve grafting was used in 10 cases. Patients' facial movements were documented by a three-dimensional video analysis system preoperatively and 6, 12, 18, and 24 months postoperatively. For this comparative study, only the data of patients with preoperative and 12-month postoperative measurements were included. In the 27 patients with a final result after temporalis muscle transposition for eye closure, the distance between the upper and lower eyelid points during eye closing (as for sleep) was reduced from 10.33 +/- 2.43 mm (mean +/- SD) preoperatively to 5.84 +/- 4.34 mm postoperatively on the paralyzed side, compared with 0.0 +/- 0.0 mm preoperatively and postoperatively on the contralateral healthy side. In the resting position, preoperative values for the paralyzed side changed from 15.11 +/- 1.92 mm preoperatively to 13.46 +/- 1.94 mm postoperatively, compared with 12.17 +/- 2.02 mm preoperatively and 12.05 +/- 1.95 mm postoperatively on the healthy side. In the nine patients with a final result after surgery using a part of the free gracilis muscle transplant reinnervated by a zygomatic branch of the contralateral healthy side through a cross-face nerve graft, eyelid closure changed from 10.21 +/- 2.72 mm to 1.68 +/- 1.35 mm

  7. Impact of Climate Change on Drought in the Upstream Yangtze River Region

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    Guihua Lu

    2016-12-01

    Full Text Available Based on Coupled Model Intercomparison Project Phase 5 (CMIP5 dataset and a variable infiltration capacity (VIC hydrological model, this study assesses the possible influence of climate change in the upstream region of the Yangtze River on droughts in the future 30 years. Long-term daily soil moisture content were simulated by VIC model at a 50 km × 50 km resolution from 1951 to 2013. Regional historical drought events were then recognized based on soil moisture anomaly percentage index and validated with field data. Five relatively independent representative global circulation models were selected and the outputs of them were downscaled temporally and spatially as the inputs of VIC model for daily soil moisture content simulations both in the period of 1971–2000 for the present-day climate and in the period of 2021–2050 for the future. The results show that the projected annual mean temperature is likely to increase from 1.4 °C to 1.8 °C. The projected change in mean annual precipitation could be increased slightly by 0.6% to 1.3%, but the trend of precipitation change in summer and autumn might be opposite of that. Comparing the drought characteristics values recognized in 1971–2000, seven to eight additional regional drought events are likely to happen in 2021–2050. Drought duration and drought intensity are also likely to extend for 18 d to 25 d and increase by 1.2% to 6.2%, respectively. But, drought area could decrease slightly by 1.3% to 2.7% on average. These changes in drought characteristics values suggest that regional drought could become more severely prolonged and frequent in future.

  8. Greenhouse gas emissions of different land uses in the delta region of Red River, Vietnam

    Science.gov (United States)

    Zhou, Minghua; Ha, Thu; An, Ngo The; Brüggemann, Nicolas

    2017-04-01

    Agricultural activities are responsible for up to a third of total anthropogenic GHG emissions. The subtropical/tropical delta areas of the large rivers in Southeast Asia are long-term history agricultural regions in the world. However, due to lack of field measurements, the estimation of the contribution of agro-ecosystems in the subtropical/tropical delta areas to global greenhouse gas emissions remains largely uncertain. Here, we conducted field experiments since January 2016 to quantify greenhouse gases (CO2, CH4 and N2O) emissions from four agricultural land uses of annual rice-rice, rice-vegetable, continuous vegetable system and fish pond in Red River delta region of Vietnam by using the transparent static chamber-gas chromatography technique. Higher N2O emissions were observed in the rice-vegetable and continuous vegetable systems, while lower N2O emissions were observed in the rice-rice and find pond systems. Compared to rice-rice system the cumulative N2O fluxes were on average twenty-fold higher in the rice-vegetable and continuous vegetable systems but significantly lower (75%) in the fish pond. Overall the net CO2 sinks were observed in the rice-rice system while other three land uses of rice-vegetable, continuous vegetable and fish pond acted as the net CO2 sources. The rice-rice and fish pond showed net CH4 emissions while variations of CH4 emissions (i.e. shifting between sources and sinks) along variations of soil moisture and temperature were observed in rice-vegetable and continuous vegetable systems. Compared to rice-rice system, the cumulative CH4 fluxes were significantly decreased by 100% for continuous vegetable system, 94% for rice-vegetable system and 89% for fish pond. Overall, the data suggest that conversion of traditional rice-rice paddy system to rice-vegetable, continuous vegetable system and find pond, which are currently undergoing driven by the economical requests and environmental changes (e.g., salinity intrusion) in this delta

  9. THE HISTORY OF REGIONAL DEVELOPMENT IN THE SINOS RIVER VALLEY: THE CASE OF SAPIRANGA AND ITS COURSE THROUGH TIME

    Directory of Open Access Journals (Sweden)

    Daniel Luciano Gevehr

    2016-05-01

    Full Text Available The present study aims at analyzing the dynamics of regional development in the Sinos River Valley, located in the metropolitan region of Porto Alegre (RS, considering a specific spatial and temporal frame, which is the city of Sapiranga and its development course since the end of the 19th century. To do so, we have sought to discuss the historicity of such context, by investigating to what extent regional, national and global factors are articulated in the transformation process the city has gone through. Bu considering certain historical conditions, we have attempted to identify the elements that have contributed to the economic, political, social and cultural development of Sapiranga, specifically in as much as its urban area is concerned. We have paid special attention to the aspects pertaining to the local scope, which have enabled us to achieve a better understanding of the changes this community has gone through in the regional context of the Sinos River Valley.

  10. Expected changes in future temperature extremes and their elevation dependency over the Yellow River source region

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    Y. Hu

    2013-07-01

    Full Text Available Using the Statistical DownScaling Model (SDSM and the outputs from two global climate models, we investigate possible changes in mean and extreme temperature indices and their elevation dependency over the Yellow River source region for the two future periods 2046–2065 and 2081–2100 under the IPCC SRES A2, A1B and B1 emission scenarios. Changes in interannual variability of mean and extreme temperature indices are also analyzed. The validation results show that SDSM performs better in reproducing the maximum temperature-related indices than the minimum temperature-related indices. The projections show that by the middle and end of the 21st century all parts of the study region may experience increases in both mean and extreme temperature in all seasons, along with an increase in the frequency of hot days and warm nights and with a decrease in frost days. By the end of the 21st century, interannual variability increases in all seasons for the frequency of hot days and warm nights and in spring for frost days while it decreases for frost days in summer. Autumn demonstrates pronounced elevation-dependent changes in which around six out of eight indices show significant increasing changes with elevation.

  11. Volatile Organic Compound (VOC measurements in the Pearl River Delta (PRD region, China

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    Chih-chung Chang

    2008-03-01

    Full Text Available We measured levels of ambient volatile organic compounds (VOCs at seven sites in the Pearl River Delta (PRD region of China during the Air Quality Monitoring Campaign spanning 4 October to 3 November 2004. Two of the sites, Guangzhou (GZ and Xinken (XK, were intensive sites at which we collected multiple daily canister samples. The observations reported here provide a look at the VOC distribution, speciation, and photochemical implications in the PRD region. Alkanes constituted the largest percentage (>40% in mixing ratios of the quantified VOCs at six sites; the exception was one major industrial site that was dominated by aromatics (about 52%. Highly elevated VOC levels occurred at GZ during two pollution episodes; however, the chemical composition of VOCs did not exhibit noticeable changes during these episodes. We calculated the OH loss rate to estimate the chemical reactivity of all VOCs. Of the anthropogenic VOCs, alkenes played a predominant role in VOC reactivity at GZ, whereas the contributions of reactive aromatics were more important at XK. Our preliminary analysis of the VOC correlations suggests that the ambient VOCs at GZ came directly from local sources (i.e., automobiles; those at XK were influenced by both local emissions and transportation of air mass from upwind areas.

  12. Projected changes in atmospheric river events in Arizona as simulated by global and regional climate models

    Science.gov (United States)

    Rivera, Erick R.; Dominguez, Francina

    2016-09-01

    Inland-penetrating atmospheric rivers (ARs) affect the United States Southwest and significantly contribute to cool season precipitation. In this study, we examine the results from an ensemble of dynamically downscaled simulations from the North American Regional Climate Change Assessment Program (NARCCAP) and their driving general circulation models (GCMs) in order to determine statistically significant changes in the intensity of the cool season ARs impacting Arizona and the associated precipitation. Future greenhouse gas emissions follow the A2 emission scenario from the Intergovernmental Panel on Climate Change Fourth Assessment Report simulations. We find that there is a consistent and clear intensification of the AR-related water vapor transport in both the global and regional simulations which reflects the increase in water vapor content due to warmer atmospheric temperatures, according to the Clausius-Clapeyron relationship. However, the response of AR-related precipitation intensity to increased moisture flux and column-integrated water vapor is weak and no significant changes are projected either by the GCMs or the NARCCAP models. This lack of robust precipitation variations can be explained in part by the absence of meaningful changes in both the large-scale water vapor flux convergence and the maximum positive relative vorticity in the GCMs. Additionally, some global models show a robust decrease in relative humidity which may also be responsible for the projected precipitation patterns.

  13. River Profile Analysis Using ASTER DEM: the case study in the Puqu Fault Region

    Science.gov (United States)

    Lu, P.; Shang, Y.

    2016-12-01

    Puqu Fault, as one of the two easternmost branches of the famous Jiali Fault, is not only influ- enced by the eastward extrusion of the northern Tibet, but also suffers the clockwise rotation followed by the southward extrusion. As a result, the Puqu Fault is bounded by the principal dynamic zones and the tectonics behaves active and variable along the fault. Because of the precipitous topography, it makes researchers difficult to reach to the field and thus few re- search has been conducted in that area. The study focuses on the application of remote sensing techniques in extracting tectonics from topography. High resolution Digital Elevation Model (20 meters resolution) generated from ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) stereo pair is used to extract the river network in the fault region. In addition, slope and drainage area indices are calculated from Digital Elevation Model. Based on the stream power law, we make area-slope plot of the streams so as to derive the channel concavity and steepness which are related closely to the tectonics activities. The result shows that the surface uplift varies significantly in the Puqu Fault region. The great variance occurs with the advent of significant bend along the fault. Still, for the single channel, the uplift tends to behave higher towards the direction of upper segment. The whole results are expected to be connected to the future field works and possible studies of neotectonics in the southeastern Tibet.

  14. Estimation of underground river water availability based on rainfall in the Maros karst region, South Sulawesi

    Science.gov (United States)

    Arsyad, Muhammad; Ihsan, Nasrul; Tiwow, Vistarani Arini

    2016-02-01

    Maros karst region, covering an area of 43.750 hectares, has water resources that determine the life around it. Water resources in Maros karst are in the rock layers or river underground in the cave. The data used in this study are primary and secondary data. Primary data includes characteristics of the medium. Secondary data is rainfall data from BMKG, water discharge data from the PSDA, South Sulawesi province in 1990-2010, and the other characteristics data Maros karst, namely cave, flora and fauna of the Bantimurung Bulusaraung National Park. Data analysis was conducted using laboratory test for medium characteristics Maros karst, rainfall and water discharge were analyzed using Minitab Program 1.5 to determine their profile. The average rainfall above 200 mm per year occurs in the range of 1999 to 2005. The availability of the water discharge at over 50 m3/s was happened in 1993 and 1995. Prediction was done by modeling Autoregressive Integrated Moving Average (ARIMA), with the rainfall data shows that the average precipitation for four years (2011-2014) will sharply fluctuate. The prediction of water discharge in Maros karst region was done for the period from January to August in 2011, including the type of 0. In 2012, the addition of the water discharge started up in early 2014.

  15. DDT concentration in fish from the Tapajós River in the Amazon region, Brazil.

    Science.gov (United States)

    Mendes, Rosivaldo de Alcântara; Lopes, Anna Sylmara da Costa; de Souza, Larissa Costa; Lima, Marcelo de Oliveira; Santos, Lourivaldo da Silva

    2016-06-01

    DDT and metabolites were measured in six species of fish collected from the Tapajós River in the village of Barreiras, near the town of Itaituba in the Brazilian Amazon region. The selected fish were the most consumed and economically important to the local people. DDT was used frequently in this region for malaria control. Fish samples were analyzed after extraction by microwave-assisted extraction in hexane/acetone (8:2, v/v) by gas chromatography with electron capture detector. Residues of op'-DDT and pp'-DDT and metabolites were detected, including pp'-DDE, pp'-DDD, op'-DDT, and op'-DDE, in 98% of the samples, with a greater abundance of pp'-DDT. Total DDT levels were 7.1-249.5 ng g(-1) wet weight (w.w). The DDE/DDT ratio was low, indicating recent exposure to DDT. The study area that may be related to generated waste used in public health campaigns to combat mosquitos (Anopheles spp.), still present in the Amazon environment, that transmit malaria. DDT levels and metabolites found in fish species do not present risks to human health because they are below acceptable limits for consumption.

  16. Emergy Synthesis and Regional Sustainability Assessment: Case Study of Pan-Pearl River Delta in China

    Directory of Open Access Journals (Sweden)

    Guomin Li

    2014-08-01

    Full Text Available In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy density based on flat land area is mapped to reflect the intensity of emergy use in human activity areas. Results show the following: (1 the current development path of the PPRD region, with the value of emergy sustainability index (ESI = 0.227 significantly lower than one, is unsustainable in the long run; (2 Guangdong has the lowest ESI value (0.071, and the ESI values of Fujian, Guangxi, Hunan and Jiangxi are lower than 0.5, indicating that the economy in these provinces overly relies on non-renewable and imported resources; (3 Guizhou has a high emergy yield rate and is thus the main energy supplier in PPRD; and (4 among the nine provinces in PPRD, only Hainan has an ESI value (2.145 higher than one.

  17. Assessment of Water Quality of Subarnarekha River in Balasore Region, Odisha, India

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    A. A Karim

    2014-08-01

    Full Text Available The present study was carried out to determine the water quality status of Subarnarekha River at Balasore region during pre-project period as Kirtania Port is proposed in this area. River water samples were analysed for physico-chemical parameters by following standard methods (APHA 1985 and the results showed their variations as follows: pH 7.3-7.8,Temperature 26.7-28.20C, Electrical Conductivity 392-514 µ mho ,Total suspended solids 118-148 mg/l, Total dissolved solids 241-285 mg/l, Alkalinity 27.3-42 mg/l, Total Hardness 64.63-114.06 mg/l, Calcium 24.6-32 mg/l, Magnesium 9.72-13.8 mg/l, Dissolved Oxygen 4.6-5.3 mg/l, Biochemical oxygen demand 1.1-3.39 mg/l, Chemical oxygen demand 53-147 mg/l, Nitrates 0.4-1.06 mg/l, Phosphates 0.86-2.4 mg/l, Sulphates 113-143 mg/l, Chlorides 26.32-36.63 mg/l, Iron 0.224-0.464 mg/l, Chromium 0.008-0.016 mg/l. The analysed physico-chemical parameters were almost not exceeded the maximum permissible limit of Indian standards (IS: 10500. After physico-chemical analysis, water quality index (WQI was established from twelve important various physiochemical parameters by following weighted arithmetic index method. The calculated water quality index indicates that the quality of water was good and hence fit for use.

  18. An Experience of Statistical Method Application in Forest Survey at Angara River Region in 1932

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    L. N. Vashchuk

    2014-10-01

    Full Text Available Report of the Angara forest economic expedition of forest economic survey in 1932 on the left bank of the Angara River has been found. The survey covered a part of Krasnoyarsk Territory and Irkutsk region, a total area of 18641.8 thousand ha. The report describes technology of forest inventory and achievements that have not previously been published. The survey was conducted by statistical method, which consisted of a sample by a continuous forest inventory enumeration of trees on sample plots (SP, arranged in an array on a particular system, followed by mathematical-statistical recalculation of the sample results to the entire survey. To do this, strip finders (sights were cut in the latitudinal direction at a distance from one another at 16 km. On the hacked sights, by every 2 km, 0.1 ha (10 × 100 m SP were established. In total 32 forest inventory sights were hacked, with total length of 9931 km, which incorporated 4817 SP. The accuracy of forest resources’ inventory characteristics determining also was investigated using smaller sample plots. For this purpose, each of the SP were cut to smaller area of 0.01 ha (10 × 10 m, where independent continuous enumeration of trees was conducted, andsample trees were cut, measured and bucked to the assortments, to explore the tree stand assortment structure. At each «sample cutting area» all the trees were felled out from 44 cm and above DBH. At half of the sample plot with 5 × 10 m size, located in the eastern end, all the trees were felled out and measured from 24 cm and above DBH. Every four «sample cutting area» in the fifth, all the trees with 12 cm and above DBH were cut down and measured. According to the results of the work, a detailed description of forest resources in the whole Angara river basin, and across 17 forest exploitation areas was completed.

  19. Impact of resolution on regional climate modeling in the source region of Yellow River with complex terrain using RegCM3

    Science.gov (United States)

    Hui, Pinhong; Tang, Jianping; Wang, Shuyu; Wu, Jian; Niu, Xiaorui; Kang, Yue

    2016-07-01

    This paper presents results from a 20-year (1990-2009) simulation by RegCM3 with both 45- and 15-km horizontal resolutions. The research focuses on the source region of Yellow River and its surrounding area, which is located on the northeast edge of the Tibetan Plateau with its very complex topography. Driven by the ECMWF ERA-interim reanalysis data, RegCM3 displays reasonable ability to reproduce the spatial patterns, annual cycles, and the interannual variabilities of regional surface climate, though the model shows wet and cold bias. The model's performance is more close to observation for the source region of Yellow River than the other part of the analysis region, and the application of high resolution of 15 km demonstrates better skill with less bias for mean climate and larger correlation coefficients for interannual variability at most stations. However, the high-resolution simulation shows little advantage for reproducing the variations of precipitation and surface air temperature with altitude. The RegCM3 model also generally reproduces the probability distribution functions (PDFs) of surface climate and, consequently, the occurrence of climatic extremes and extreme indices. The simulation with high resolution again proves to be more reliable to generate climatic extremes over complex terrain of the source region of the Yellow River, related to its better representation of complex terrain and local processes.

  20. DNA methylation of Sleeping Beauty with transposition into the mouse genome.

    Science.gov (United States)

    Park, Chang Won; Kren, Betsy T; Largaespada, David A; Steer, Clifford J

    2005-08-01

    The Sleeping Beauty transposon is a recently developed non-viral vector that can mediate insertion of transgenes into the mammalian genome. Foreign DNA elements that are introduced tend to invoke a host-defense mechanism resulting in epigenetic changes, such as DNA methylation, which may induce transcriptional inactivation of mammalian genes. To assess potential epigenetic modifications associated with Sleeping Beauty transposition, we investigated the DNA methylation pattern of transgenes inserted into the mouse genome as well as genomic regions flanking the insertion sites with bisulfite-mediated genomic sequencing. Transgenic mouse lines were created with two different Sleeping Beauty transposons carrying either the Agouti or eGFP transgene. Our results showed that DNA methylation in the keratin-14 promoter and Agouti transgene were negligible. In addition, two different genomic loci flanking the Agouti insertion site exhibited patterns of DNA methylation similar to wild-type mice. In contrast, high levels of DNA methylation were observed in the eGFP transgene and its ROSA26 promoter. These results indicate that transposition via Sleeping Beauty into the mouse genome may result in a significant level of de novo DNA methylation. This may depend on a number of different factors including the cargo DNA sequence, chromosomal context of the insertion site, and/or host genetic background.

  1. Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region, South China.

    Science.gov (United States)

    Liu, Hong; Cui, Kunyan; Zeng, Feng; Chen, Lixuan; Cheng, Yating; Li, Huiru; Li, Shuocong; Zhou, Xi; Zhu, Fang; Ouyang, Gangfeng; Luan, Tiangang; Zeng, Zunxiang

    2014-06-15

    Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ16PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3 μg g(-1) dry weight (dw), with the mean and median concentrations of 5.34 μg g(-1) dw and 2.15 μg g(-1) dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12 μg g(-1)dw, 0.420 μg g(-1) dw and 3.72 μg g(-1) dw, and 0.429 μg g(-1) dw, 0.152 μg g(-1) dw and 1.55 μg g(-1) dw, respectively, and accounted for 94.2-99.7% of the Σ16PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.

  2. Regional distribution of mercury in sediments of the main rivers of French Guiana (Amazonian basin).

    Science.gov (United States)

    Laperche, Valérie; Hellal, Jennifer; Maury-Brachet, Régine; Joseph, Bernard; Laporte, Pierre; Breeze, Dominique; Blanchard, François

    2014-01-01

    Use of mercury (Hg) for gold-mining in French Guiana (up until 2006) as well as the presence of naturally high background levels in soils, has led to locally high concentrations in soils and sediments. The present study maps the levels of Hg concentrations in river sediments from five main rivers of French Guiana (Approuague River, Comté River, Mana River, Maroni River and Oyapock River) and their tributaries, covering more than 5 450 km of river with 1 211 sampling points. The maximum geological background Hg concentration, estimated from 241 non-gold-mined streams across French Guiana was 150 ng g(-1). Significant differences were measured between the five main rivers as well as between all gold-mining and pristine areas, giving representative data of the Hg increase due to past gold-mining activities. These results give a unique large scale vision of Hg contamination in river sediments of French Guiana and provide fundamental data on Hg distribution in pristine and gold-mined areas.

  3. Study on the changes of water cycle and its impacts in the source region of the Yellow River

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Shifeng; JIA; Shaofeng; LIU; Changming; CAO; Wenbi

    2004-01-01

    The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of China in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

  4. River

    Directory of Open Access Journals (Sweden)

    Morel Mathieu

    2016-01-01

    Full Text Available The OECD report “Boosting Resilience through Innovative Risk Governance” examines the efforts of OECD countries to prevent or reduce future disaster impacts, and highlights several key areas where improvements can be made. International collaboration is insufficiently utilised to address shocks that have increasingly global consequences. Institutional design plays a significant role in facilitating or hampering the engagement and investments of governmental and non-governmental stakeholders in disaster risk prevention and mitigation. To inform the design of “better” institutions, the OECD proposes the application of a diagnostic framework that helps governments identify institutional shortcomings and take actions to improve them. The goal of the case study on the Rhone River is to conduct an analysis of the progress, achievements and existing challenges in designing and implementing disaster risk reduction strategies through the Rhone Plan from a comparative perspective across a set of selected countries of this study, like Austria and Switzerland, will inform how to improve institutional frameworks governing risk prevention and mitigation. The case study will be used to identify examples of successful practice taking into account their specific country contexts, and analyse their potential for policy transfer.

  5. Spatio-temporal changes of NDVI and its relation with climatic variables in the source regions of the Yangtze and Yellow rivers

    Institute of Scientific and Technical Information of China (English)

    YANG Zhaoping; GAO Jixi; ZHOU Caiping; SHI Peili; ZHAO Lin; SHEN Wenshou; OUYANG Hua

    2011-01-01

    The source regions of the Yangtze and Yellow rivers are important water conservation areas of China.In recent years,ecological deterioration trend of the source regions caused by global climate change and unreasonable resource development increased gradually.In this paper,the spatial distribution and dynamic change of vegetation cover in the source regions of the Yangtze and Yellow rivers are analyzed in recent 10 years based on 1-km resolution multi-temporal SPOTVGT-DN data from 1998 to 2007.Meanwhile,the correlation relationships between air temperature,precipitation,shallow ground temperature and NDVl,which is 3×3 pixel at the center of Wudaoliang,Tuotuohe,Qumalai,Maduo,and Dari meteorological stations were analyzed.The results show that the NDVI values in these two source regions are increasing in recent 10 years.Spatial distribution of NDVl which was consistent with hydrothermal condition decreased from southeast to northwest of the source regions.NDVl with a value over 0.54 was mainly distributed in the southeastern source region of the Yellow River,and most NDVI values in the northwestern source region of the Yangtze River were less than 0.22.Spatial changing trend of NDVI has great difference and most parts in the source regions of the Yangtze and Yellow rivers witnessed indistinct change.The regions with marked increasing trend were mainly distributed on the south side of the Tongtian River,some part of Keqianqu,Tongtian,Chumaer,and Tuotuo rivers in the source region of the Yangtze River and Xingsuhai,and southern Dari county in the source region of the Yellow River.The regions with very marked increasing tendency were mainly distributed on the south side of Tongtian Rriver and sporadically distributed in hinterland of the source region of the Yangtze River.The north side of Tangula Range in the source region of the Yangtze River and Dari and Maduo counties in the source region of the Yellow River were areas in which NDVI changed with marked decreasing

  6. Seasonal variations of anhydrosugars in PM2.5 in the Pearl River Delta Region, China

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    Kin Fai Ho

    2014-06-01

    Full Text Available Anhydrosugars including levoglucosan and mannosan are the most effective organic tracers for biomass burning aerosol in the atmosphere. In this study, to investigate the contribution of biomass burning emissions to the aerosol burden in the Pearl River Delta (PRD region, China, 24-hour integrated PM2.5 samples were collected simultaneously at four locations, (i Guangzhou (GZ, (ii Zhaoqing (ZQ in Guangdong province, (iii Hok Tsui (HT and (iv Hong Kong Polytechnic University (PU in Hong Kong, in four seasons between 2006 and 2007. Levoglucosan and mannosan, together with water-soluble inorganic ions and water-soluble organic carbon (WSOC, were determined to elucidate the seasonal and spatial variations in biomass burning contributions. The concentrations of levoglucosan and mannosan were on average 82.4±123 and 5.8±8.6 ng m−3, respectively. The WSOC concentrations ranged from 0.2 to 9.4 µg m−3, with an average of 2.1±1.6 µg m−3. The relative contributions of biomass burning emissions to OC were 33% in QZ, 12% in GZ, 4% at PU and 5% at HT, respectively, estimated by the measured levoglucosan to organic carbon ratio (LG/OC relative to literature-derived LG/OC values. The contributions from biomass burning emissions were in general 1.7–2.8 times higher in winter than those in other seasons. Further, it was inferred from diagnostic tracer ratios that a significant fraction of biomass burning emissions was derived from burning of hard wood and likely also from field burning of agricultural residues, such as rice straw, in the PRD region. Our results highlight the contributions from biomass/biofuel burning activities on the regional aerosol budget in South China.

  7. A nucleolus-predominant piggyBac transposase, NP-mPB, mediates elevated transposition efficiency in mammalian cells.

    Science.gov (United States)

    Hong, Jin-Bon; Chou, Fu-Ju; Ku, Amy T; Fan, Hsiang-Hsuan; Lee, Tung-Lung; Huang, Yung-Hsin; Yang, Tsung-Lin; Su, I-Chang; Yu, I-Shing; Lin, Shu-Wha; Chien, Chung-Liang; Ho, Hong-Nerng; Chen, You-Tzung

    2014-01-01

    PiggyBac is a prevalent transposon system used to deliver transgenes and functionally explore the mammalian untouched genomic territory. The important features of piggyBac transposon are the relatively low insertion site preference and the ability of seamless removal from genome, which allow its potential uses in functional genomics and regenerative medicine. Efforts to increase its transposition efficiency in mammals were made through engineering the corresponding transposase (PBase) codon usage to enhance its expression level and through screening for mutant PBase variants with increased enzyme activity. To improve the safety for its potential use in regenerative medicine applications, site-specific transposition was achieved by using engineered zinc finger- and Gal4-fused PBases. An excision-prone PBase variant has also been successfully developed. Here we describe the construction of a nucleolus-predominant PBase, NP-mPB, by adding a nucleolus-predominant (NP) signal peptide from HIV-1 TAT protein to a mammalian codon-optimized PBase (mPB). Although there is a predominant fraction of the NP-mPB-tGFP fusion proteins concentrated in the nucleoli, an insertion site preference toward nucleolar organizer regions is not detected. Instead a 3-4 fold increase in piggyBac transposition efficiency is reproducibly observed in mouse and human cells.

  8. Different Points of View Concerning the Didactic Transposition

    Directory of Open Access Journals (Sweden)

    Késia Caroline Ramires Neves

    2011-10-01

    Full Text Available The present article treats the concept of Didactic Transposition, taking as reference the work of Yves Chevallard, La transposición didáctica: del saber sabio al saber enseñado (2005. We compared the adduction of the concept in several works, such as thesis, dissertations and articles, and discussed the multiple impressions concerning the process of didactic transposition. These papers show that the conceptualizations are not well defined, entailing dubiousness and discussions. Some differences accrue from different areas of science, distinct of mathematics, others are inherent on the original ideas in Chevallard (2005, paper that served as bibliographical reference for the majority of the studied works.

  9. Modified Shumacker repair of transposition of the great arteries.

    Science.gov (United States)

    Waldhausen, J A; Pierce, W S; Berman, W; Whitman, V

    1979-08-01

    Seven infants weighing from 6.4 to 10.3 kg underwent correction of transposition of the great arteries by the venous transposition operation as described by Shumacker. In this operation, a new atrial septum is constructed using a bipedicled right atrial flap, and the lateral atrial wall is constructed using a viable pericardial flap. Three of the patients had an associated ventricular septal defect. Six of the seven patients survived and have had an excellent clinical result. Although atrial arrhythmias were common in the early postoperative period, all patients are now in sinus rhythm. Two patients have had postoperative cardiac catheterization and cineangiography, which showed excellent hemodynamic results. The modified Shumacker operation preserves two of the three internodal pathways, provides a compliant, viable atrial septum, and permits fabrication of a generous-size physiological left atrium. This appears to offer advantages not present in the Mustard procedure.

  10. Corrected transposition of great arteries; Skorygowane przelozenie wielkich pni tetniczych

    Energy Technology Data Exchange (ETDEWEB)

    Erecinski, J.; Aleszewicz-Baranowska, J.; Chojnicki, M.; Sabiniewicz, R. [Inst. Pediatrii, Akademia Medyczna, Gdansk (Poland)

    1995-12-31

    20 patients with the diagnosis of congenital corrected transposition of great arteries were analyzed. The diagnosis was based on routine clinical examination, echocardiography and in certain cases on heart catheterization and angiocardiography. In the most cases c-TGA coexists with additional heart defects. The commonest coexisting defects were: ventricular septal defect (60%), pulmonary stenosis (50%), atrio-ventricular valve regurgitation, predominantly systemic (tricuspid 45%). In the most cases 2D Doppler echo examination was sufficient for morphological assessment. In order to quality to cardiosurgical treatment heart catheterization and angiocardiography were necessary. 5 children were treated surgically. 3 of them underwent palliative procedures, one - Rastelli procedure and one had corrective surgery with bad result. Clinical picture of corrected transposition of great arteries is determined by coexisting additional heart defects. (author) 15 refs, 6 figs, 1 tab

  11. Temporal fluctuation of multidrug resistant salmonella typhi haplotypes in the mekong river delta region of Vietnam.

    Directory of Open Access Journals (Sweden)

    Kathryn E Holt

    Full Text Available BACKGROUND: typhoid fever remains a public health problem in Vietnam, with a significant burden in the Mekong River delta region. Typhoid fever is caused by the bacterial pathogen Salmonella enterica serovar Typhi (S. Typhi, which is frequently multidrug resistant with reduced susceptibility to fluoroquinolone-based drugs, the first choice for the treatment of typhoid fever. We used a GoldenGate (Illumina assay to type 1,500 single nucleotide polymorphisms (SNPs and analyse the genetic variation of S. Typhi isolated from 267 typhoid fever patients in the Mekong delta region participating in a randomized trial conducted between 2004 and 2005. PRINCIPAL FINDINGS: the population of S. Typhi circulating during the study was highly clonal, with 91% of isolates belonging to a single clonal complex of the S. Typhi H58 haplogroup. The patterns of disease were consistent with the presence of an endemic haplotype H58-C and a localised outbreak of S. Typhi haplotype H58-E2 in 2004. H58-E2-associated typhoid fever cases exhibited evidence of significant geo-spatial clustering along the Sông H u branch of the Mekong River. Multidrug resistance was common in the established clone H58-C but not in the outbreak clone H58-E2, however all H58 S. Typhi were nalidixic acid resistant and carried a Ser83Phe amino acid substitution in the gyrA gene. SIGNIFICANCE: the H58 haplogroup dominates S. Typhi populations in other endemic areas, but the population described here was more homogeneous than previously examined populations, and the dominant clonal complex (H58-C, -E1, -E2 observed in this study has not been detected outside Vietnam. IncHI1 plasmid-bearing S. Typhi H58-C was endemic during the study period whilst H58-E2, which rarely carried the plasmid, was only transient, suggesting a selective advantage for the plasmid. These data add insight into the outbreak dynamics and local molecular epidemiology of S. Typhi in southern Vietnam.

  12. Early mixed farming of millet and rice 7800 years ago in the Middle Yellow River region, China.

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    Jianping Zhang

    Full Text Available The Peiligang Culture (9000-7000 cal. yr BP in the Middle Yellow River region, North China, has long been considered representative of millet farming. It is still unclear, however, if broomcorn millet or foxtail millet was the first species domesticated during the Peiligang Culture. Furthermore, it is also unknown whether millet was cultivated singly or together with rice at the same period. In this study, phytolith analysis of samples from the Tanghu archaeological site reveals early crop information in the Middle Yellow River region, China. Our results show that broomcorn millet was the early dry farming species in the Peiligang Culture at 7800 cal. yr BP, while rice cultivation took place from 7800 to 4500 cal. yr BP. Our data provide new evidence of broomcorn millet and rice mixed farming at 7800 cal. yr BP in the Middle Yellow River region, which has implications for understanding the domestication process of the two crops, and the formation and continuance of the Ancient Yellow River Civilization.

  13. Early mixed farming of millet and rice 7800 years ago in the Middle Yellow River region, China.

    Science.gov (United States)

    Zhang, Jianping; Lu, Houyuan; Gu, Wanfa; Wu, Naiqin; Zhou, Kunshu; Hu, Yayi; Xin, Yingjun; Wang, Can

    2012-01-01

    The Peiligang Culture (9000-7000 cal. yr BP) in the Middle Yellow River region, North China, has long been considered representative of millet farming. It is still unclear, however, if broomcorn millet or foxtail millet was the first species domesticated during the Peiligang Culture. Furthermore, it is also unknown whether millet was cultivated singly or together with rice at the same period. In this study, phytolith analysis of samples from the Tanghu archaeological site reveals early crop information in the Middle Yellow River region, China. Our results show that broomcorn millet was the early dry farming species in the Peiligang Culture at 7800 cal. yr BP, while rice cultivation took place from 7800 to 4500 cal. yr BP. Our data provide new evidence of broomcorn millet and rice mixed farming at 7800 cal. yr BP in the Middle Yellow River region, which has implications for understanding the domestication process of the two crops, and the formation and continuance of the Ancient Yellow River Civilization.

  14. 河流功能区划初步探讨%Preliminary study on river function regionalization

    Institute of Scientific and Technical Information of China (English)

    袁弘任; 沈福新; 魏开湄

    2011-01-01

    为了促进河流自然功能、生态环境功能和社会服务功能的协调发展,维持河流健康和水资源可持续利用,分析河流功能区划的内涵、分类体系,按禁止开发区、规划保留区、调整修复区和开发治理区对河流功能进行区划,并探讨划分依据与程序,为流域规划与管理提供依据.%In order to promote the coordinated development of natural, ecological environmental and social service functions of rivers, and to maintain river health and sustainable use of water resources, the meaning and classification system of the river function regionalization were analyzed. The river function was regionalized according to the prohibitive development area, planning reserve area, adjustment restoration area and development and management area. The regionalization theory and procedure were examined, providing a basis for basin planning and management.

  15. Dextrocardia with corrected transposition of large arteries in scintigraphic picture

    Energy Technology Data Exchange (ETDEWEB)

    Farsky, S.; Lepej, J.; Hutka, Z. (Komenskeho Univ., Martin (Czechoslovakia). Lekarska Fakulta)

    1982-07-01

    A case report is presented of a patient with dextrocardia complicated with corrected transposition of the large arteries. For comparison, some findings in another patient with isolated dextrocardia are presented. Scintigrams of the heart cavities and the large vessels performed by the method of radioisotope first flow cardioangiography are shown. The ease and simplicity are pointed out of this noninvasive method in diagnosis and differential diagnosis of dextrocardia and congenital heart defects in general.

  16. Complete penoscrotal transposition: A three-stage procedure.

    Science.gov (United States)

    Somoza, Ivan; Palacios, Maria G; Mendez, Roberto; Vela, Diego

    2012-10-01

    Complete penoscrotal transposition (CPST) with an intact scrotum is a rare anomaly in which the scrotum is located cephalic to the penis. It is the most severe degree of malformation of a spectrum of abnormalities in scrotal development. There are few cases reported in the literature, and there are few descriptions of the technique for correction and results. We describe a new case of CPST and its sequential correction.

  17. Complete penoscrotal transposition: A three-stage procedure

    Directory of Open Access Journals (Sweden)

    Ivan Somoza

    2012-01-01

    Full Text Available Complete penoscrotal transposition (CPST with an intact scrotum is a rare anomaly in which the scrotum is located cephalic to the penis. It is the most severe degree of malformation of a spectrum of abnormalities in scrotal development. There are few cases reported in the literature, and there are few descriptions of the technique for correction and results. We describe a new case of CPST and its sequential correction.

  18. Impacts of urbanization on nitrogen deposition in the Pearl River Delta region, China

    Science.gov (United States)

    Wang, X.; Fan, Q.

    2015-12-01

    The Pearl River Delta (PRD) region is one of the most advanced economic districts in China, which has experienced remarkable economic development and urbanization in the past two decades. Accompanied with the rapid economy development and urbanization, the PRD region encountered both severe nitrogen pollution and deposition. In this study, the characteristics of nitrogen deposition and impacts of urbanization on nitrogen deposition in the PRD region were investigated by combining the methods of field study and numerical model. According to the field measurements, the total dry and wet atmospheric deposition of reactive N at a urban site (SYSU) was up to 55.0 kg ha-1 yr-1 in 2010, slightly lower than the results at a rural forest site (DHS) (57.6 kg ha-1 yr-1). Wet deposition was the main form of the total deposition (64-76%). Organic nitrogen (ON) was found to be dominant in the total N deposition, with a contribution of 53% at DHS and 42% at SYSU. NH4+-N and NO3--N accounted for a similar portion of the total N deposition (23-29%). Atmospheric nitrogen deposition was further simulated by using the improved WRF-Chem model. The simulated N deposition flux was high in the north of PRD (i.e., Guangzhou, Foshan, Zhaoqing) and relative low in the east (Huizhou) and south (Zhuhai), with an average N deposition flux of about 24 kg ha-1 yr-1 for the whole PRD. The distribution of N dry deposition was mainly controlled by the concentration of reactive N compounds and precipitation governed the wet deposition distribution. The modeling results also indicate that the PRD area is the source region in which the emissions exceed the deposition while the outside area of the PRD is the receptor region in which the deposition exceeds emissions. The impact of emission change and land use change due to urbanization was also investigated using the WRF-Chem model. The results showed that atmospheric N deposition exhibits a direct response to emission change while the land use change

  19. Regulated complex assembly safeguards the fidelity of Sleeping Beauty transposition.

    Science.gov (United States)

    Wang, Yongming; Pryputniewicz-Dobrinska, Diana; Nagy, Enikö Éva; Kaufman, Christopher D; Singh, Manvendra; Yant, Steve; Wang, Jichang; Dalda, Anna; Kay, Mark A; Ivics, Zoltán; Izsvák, Zsuzsanna

    2017-01-09

    The functional relevance of the inverted repeat structure (IR/DR) in a subgroup of the Tc1/mariner superfamily of transposons has been enigmatic. In contrast to mariner transposition, where a topological filter suppresses single-ended reactions, the IR/DR orchestrates a regulatory mechanism to enforce synapsis of the transposon ends before cleavage by the transposase occurs. This ordered assembly process shepherds primary transposase binding to the inner 12DRs (where cleavage does not occur), followed by capture of the 12DR of the other transposon end. This extra layer of regulation suppresses aberrant, potentially genotoxic recombination activities, and the mobilization of internally deleted copies in the IR/DR subgroup, including Sleeping Beauty (SB). In contrast, internally deleted sequences (MITEs) are preferred substrates of mariner transposition, and this process is associated with the emergence of Hsmar1-derived miRNA genes in the human genome. Translating IR/DR regulation to in vitro evolution yielded an SB transposon version with optimized substrate recognition (pT4). The ends of SB transposons excised by a K248A excision(+)/integration(-) transposase variant are processed by hairpin resolution, representing a link between phylogenetically, and mechanistically different recombination reactions, such as V(D)J recombination and transposition. Such variants generated by random mutation might stabilize transposon-host interactions or prepare the transposon for a horizontal transfer.

  20. Regulated complex assembly safeguards the fidelity of Sleeping Beauty transposition

    Science.gov (United States)

    Wang, Yongming; Pryputniewicz-Dobrinska, Diana; Nagy, Enikö Éva; Kaufman, Christopher D.; Singh, Manvendra; Yant, Steve; Wang, Jichang; Dalda, Anna; Kay, Mark A.; Ivics, Zoltán; Izsvák, Zsuzsanna

    2017-01-01

    The functional relevance of the inverted repeat structure (IR/DR) in a subgroup of the Tc1/mariner superfamily of transposons has been enigmatic. In contrast to mariner transposition, where a topological filter suppresses single-ended reactions, the IR/DR orchestrates a regulatory mechanism to enforce synapsis of the transposon ends before cleavage by the transposase occurs. This ordered assembly process shepherds primary transposase binding to the inner 12DRs (where cleavage does not occur), followed by capture of the 12DR of the other transposon end. This extra layer of regulation suppresses aberrant, potentially genotoxic recombination activities, and the mobilization of internally deleted copies in the IR/DR subgroup, including Sleeping Beauty (SB). In contrast, internally deleted sequences (MITEs) are preferred substrates of mariner transposition, and this process is associated with the emergence of Hsmar1-derived miRNA genes in the human genome. Translating IR/DR regulation to in vitro evolution yielded an SB transposon version with optimized substrate recognition (pT4). The ends of SB transposons excised by a K248A excision+/integration- transposase variant are processed by hairpin resolution, representing a link between phylogenetically, and mechanistically different recombination reactions, such as V(D)J recombination and transposition. Such variants generated by random mutation might stabilize transposon-host interactions or prepare the transposon for a horizontal transfer. PMID:27913727

  1. Performance Analysis of Transposition Models Simulating Solar Radiation on Inclined Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yu; Sengupta, Manajit

    2016-06-02

    Transposition models have been widely used in the solar energy industry to simulate solar radiation on inclined photovoltaic panels. Following numerous studies comparing the performance of transposition models, this work aims to understand the quantitative uncertainty in state-of-the-art transposition models and the sources leading to the uncertainty. Our results show significant differences between two highly used isotropic transposition models, with one substantially underestimating the diffuse plane-of-array irradiances when diffuse radiation is perfectly isotropic. In the empirical transposition models, the selection of the empirical coefficients and land surface albedo can both result in uncertainty in the output. This study can be used as a guide for the future development of physics-based transposition models and evaluations of system performance.

  2. Multispecies Fisheries in the Lower Amazon River and Its Relationship with the Regional and Global Climate Variability

    Science.gov (United States)

    Buss de Souza, Ronald; Freire, Juan; Isaac, Victoria Judith

    2016-01-01

    This paper aims to describe the spatial-temporal variability in catch of the main fishery resources of the Amazon River and floodplain lakes of the Lower Amazon, as well as relating the Catch per Unit of Effort with anomalies of some of the Amazon River, atmosphere and Atlantic Ocean system variables, determining the influence of the environment on the Amazonian fishery resources. Finfish landings data from the towns and villages of the Lower Amazon for the fisheries of three sites (Óbidos, Santarém and Monte Alegre), were obtained for the period between January 1993 and December 2004. Analysis of variance, detrended correspondence analysis, redundancy analysis and multiple regression techniques were used for the statistical analysis of the distinct time series. Fisheries production in the Lower Amazon presents differences between the Amazon River and the floodplain lakes. Production in the Amazon River is approximately half of the one of the floodplain lakes. This variability occurs both along the Lower Amazon River region (longitudinal gradient) and laterally (latitudinal gradient) for every fishing ground studied here. The distinct environmental variables alone or in association act differently on the fishery stocks and the success of catches in each fishery group studied here. Important variables are the flooding events; the soil the sea surface temperatures; the humidity; the wind and the occurence of El Niño-Southern Oscillation events. Fishery productivity presents a large difference in quantity and distribution patterns between the river and floodplain lakes. This variability occurs in the region of the Lower Amazon as well as laterally for each fishery group studied, being dependent on the ecological characteristics and life strategies of each fish group considered here. PMID:27314951

  3. Multispecies Fisheries in the Lower Amazon River and Its Relationship with the Regional and Global Climate Variability.

    Science.gov (United States)

    Pinaya, Walter Hugo Diaz; Lobon-Cervia, Francisco Javier; Pita, Pablo; Buss de Souza, Ronald; Freire, Juan; Isaac, Victoria Judith

    2016-01-01

    This paper aims to describe the spatial-temporal variability in catch of the main fishery resources of the Amazon River and floodplain lakes of the Lower Amazon, as well as relating the Catch per Unit of Effort with anomalies of some of the Amazon River, atmosphere and Atlantic Ocean system variables, determining the influence of the environment on the Amazonian fishery resources. Finfish landings data from the towns and villages of the Lower Amazon for the fisheries of three sites (Óbidos, Santarém and Monte Alegre), were obtained for the period between January 1993 and December 2004. Analysis of variance, detrended correspondence analysis, redundancy analysis and multiple regression techniques were used for the statistical analysis of the distinct time series. Fisheries production in the Lower Amazon presents differences between the Amazon River and the floodplain lakes. Production in the Amazon River is approximately half of the one of the floodplain lakes. This variability occurs both along the Lower Amazon River region (longitudinal gradient) and laterally (latitudinal gradient) for every fishing ground studied here. The distinct environmental variables alone or in association act differently on the fishery stocks and the success of catches in each fishery group studied here. Important variables are the flooding events; the soil the sea surface temperatures; the humidity; the wind and the occurence of El Niño-Southern Oscillation events. Fishery productivity presents a large difference in quantity and distribution patterns between the river and floodplain lakes. This variability occurs in the region of the Lower Amazon as well as laterally for each fishery group studied, being dependent on the ecological characteristics and life strategies of each fish group considered here.

  4. Regional-scale controls on dissolved nitrous oxide in the Upper Mississippi River

    Science.gov (United States)

    Turner, P. A.; Griffis, T. J.; Baker, J. M.; Lee, X.; Crawford, J. T.; Loken, L. C.; Venterea, R. T.

    2016-05-01

    The U.S. Corn Belt is one of the most intensive agricultural regions of the world and is drained by the Upper Mississippi River (UMR), which forms one of the largest drainage basins in the U.S. While the effects of agricultural nitrate (NO3-) on water quality in the UMR have been well documented, its impact on the production of nitrous oxide (N2O) has not been reported. Using a novel equilibration technique, we present the largest data set of freshwater dissolved N2O concentrations (0.7 to 6 times saturation) and examine the controls on its variability over a 350 km reach of the UMR. Driven by a supersaturated water column, the UMR was an important atmospheric N2O source (+68 mg N2O N m-2 yr-1) that varies nonlinearly with the NO3- concentration. Our analyses indicated that a projected doubling of the NO3- concentration by 2050 would cause dissolved N2O concentrations and emissions to increase by about 40%.

  5. Assessment of Heavy Metal in Surface Sediments of Day River at Beni-Mellal Region, Morocco

    Directory of Open Access Journals (Sweden)

    A. Barakat

    2012-08-01

    Full Text Available The Day River receives domestic and industrial untreated wastewaters from Beni-Mellal city and surrounding villages during the last decades. The present study was to obtain a preliminary assessment about the level and distribution of six heavy metals (Cd, Cr, Cu, Pb, Zn and Fe in its surface sediment collected from 13 stations. The metal concentrations (in mg/kg ranged: Cd, 0.6-6.27; Cr, 52.34-311.69; Cu, 32.69-740.75; Pb, 72.93- 140.36; Zn, 49.84-149.19; and Fe, 15670-36010. Significant spatial variation in concentrations was observed for all metals. Correlation analyses showed that metal content of sediment was controlled by organic matter and Fe contents. Pollution status was evaluated using the enrichment factor, geo-accumulation index and pollution load index and sediment quality guidelines. Based on geoaccumulation index and enrichment factors, Day sediment was treated as unpolluted to moderately polluted with Zn, Fe, Cr and Cu and moderate to considerable with Pb and Cd. Pollution load index and sediment quality guidelines showed that the metal levels exceed local and regional background concentrations, indicating contamination is high enough to be of risk to human health and ecosystem.

  6. Braided rivers, lakes and sabkhas of the upper Triassic Cifuncho formation, Atacama region, Chile

    Science.gov (United States)

    Suárez, M.; Bell, C. M.

    1994-01-01

    A 1,000-m-thickness of Upper Triassic (to possibly Hettangian) sediments of the Cifuncho Formation are exposed in the coastal Cordillera of the Atacama Region, Chile. These coarse-grained clastic terrigenous strata are interpreted as the deposits of braided rivers, ephemeral lakes, sabkhas and volcaniclastic alluvial fans. They include conglomerates, pebbly sandstones, fine to medium-grained sandstones and thin, finely-laminated limestones. Halite hopper-casts are abundant in sandstones near the top of the section. Approximately 90% of the clastic detritus was derived from an upper Paleozoic metasedimentary accretionary complex located to the west. Andesitic debris flow and pyroclastic flow deposits occur near the base of the sequence. Isolated tuff intercalations and an ignimbritic lava flow occur higher in the section. The great thickness of coarse-grained and ill-sorted clastic sediments suggests deposition in an actively subsiding basin, probably a graben, adjacent to rising highlands. Overlying Hettangian-Sinemurian marine sediments were deposited by a transgression which occurred during a world-wide lowstand. This suggests that thermal subsidence followed the Triassic rifting.

  7. Essential oils from Leptospermums of the Sunshine Coast and Northern Rivers Regions

    Directory of Open Access Journals (Sweden)

    Windsor Sarah Alison

    2012-05-01

    Full Text Available Abstract Background Around the turn of this century, the oil yield and chemical composition of Australian Leptospermum species was analysed. Since that time, research has been focused on their use as phytomedicines. The oil yield and composition of essential oils from Australian Leptospermum species directly impacts their commercialisation for medicinal use. Results The essential oils from Leptospermum (L. juniperinum, L. laevigatum, L. liversidgei, L. polygalifolium, L. semibaccatum, L. speciosum, L. trinervium and L. whitei have been examined from specimens in the Sunshine Coast (Queensland and Northern Rivers (New South Wales Regions. Both chemotypes of L. liversidgei were observed. However, only chemotype II of L. semibaccatum and chemotype I of L. trinervium were identified. The only subspecies observed of L. polygalifolium was L. polygalifolium wallum. Conclusions L. liversidgei chemotypes I and II have the potential for phytomedical use as antibacterial or anti-inflammatory agents. Chemotype I has the potential for use as an insect repellent and chemotype II may provide antifungal activity.

  8. SPATIAL AND SEASONAL DISTRIBUTIONS OF ATMOSPHERIC CARBONACEOUS AEROSOLS IN PEARL RIVER DELTA REGION, CHINA

    Institute of Scientific and Technical Information of China (English)

    Junji Cao; Shuncheng Lee; Kinfai Ho; Shichun Zou; Xiaoye Zhang; Jianguo Pan

    2003-01-01

    Concentrations and spatial distributions of organic carbon (OC) and elemental carbon (EC) in atmospheric particles were measured at 8 sites in four cities (Hong Kong, Guangzhou, Shenzhen and Zhuhai) of Pearl River Delta Region (PRDR), China during 2001 winter period and 2002 summer period. PM2.5 (particle diameter smaller than 2.5μm)and PM10 (particle diameter smaller than 10 μm) samples were collected on pre-fired quartz filters with mini-volume samplers and analyzed using thermal optical reflectance (TOR) method. The average PM2.5 and PM10 level were 60.1naceous aerosol accounted for 37.8% of the PM2.5 and 32.8% of the PM10. The highest concentrations of OC and EC were observed at Guangzhou city in both winter and summer seasons. The average OC/EC ratios were 2.4 for PM2.5and 2.5 for PM10, indicating the presence of secondary organic aerosols. The OC and EC in PRDR were found to be strongly correlated (correlation coefficients >0.6), which implied that similar emission source contribute to the ambient carbon particles.

  9. Total gaseous mercury in Pearl River Delta region, China during 2008 winter period

    Science.gov (United States)

    Li, Zheng; Xia, Chonghuan; Wang, Xinming; Xiang, Yunrong; Xie, Zhouqing

    2011-02-01

    Total gaseous mercury (TGM) was monitored at Wanqingsha, a rural site in the central Pearl River Delta region, south China from 23 November to 22 December, 2008. TGM ranged 0.50-18.67 ng m -3 with an average of 2.94 ng m -3. TGM was found to present a diurnal cycle with the maximum at 7:00-8:00 and the minimum at 14:00-16:00 (local time). The afternoon minimum in TGM were likely related to increased vertical mixing and the TGM oxidation by ozone, which was observed to negative correlation with TGM. A sudden increase in TGM from 6:00-7:00 could be due to activation of local surface emission sources by rising air temperature. Similar variations in TGM and trace gases including CO and SO 2 suggested potential anthropogenic sources contribution as well. Wind-rose patterns further indicated that the westerly wind might carry high concentration of TGM from the high mercury emission areas of Southwest China and/or local anthropogenic emission sources.

  10. Characterizing droughts under current and future climates in the Jordan River region

    Directory of Open Access Journals (Sweden)

    T. Törnros

    2013-05-01

    Full Text Available The Standardized Precipitation Index (SPI was applied in order to address the characteristics of current and future agricultural droughts in the Jordan River region located in the southeastern Mediterranean area. In the first step, the SPI was applied on spatially interpolated monthly precipitation data at multiple timescales, i.e. accumulated precipitation was considered over a number of timescales, for example: 1, 3, and 6 months. To investigate the performance of the drought index, correlation analyses were conducted with the Normalized Difference Vegetation Index (NDVI obtained from remote sensing. The results show that the 6 month SPI best explains the inter-annual variation of the NDVI. Hence, a timescale of 6 months is the most appropriate when addressing agricultural drought in the semi-arid region. In the second step, the 6 month SPI was applied to three climate projections based on the IPCC emission scenario A1B. When comparing the period 2031–2060 with 1961–1990, it is shown that the mean drought duration is projected to increase. Furthermore, the droughts are expected to become more severe because the frequency of severe and extreme droughts is projected to increase and the frequency of moderate drought is projected to decrease. To address the impact of drought on the agricultural sector, the irrigation water demand during drought was simulated with a hydrological model on a spatial resolution of 1 km. A large increase in the demand for irrigation water was simulated, showing that the agricultural sector is expected to become even more vulnerable to drought in the future.

  11. Late Quaternary glaciation of the Upper Soca River Region (Southern Julian Alps, NW Slovenia)

    Science.gov (United States)

    Bavec, Milos; Tulaczyk, Slawek M.; Mahan, Shannon; Stock, Gregory M.

    2004-01-01

    Extent of Late Quaternary glaciers in the Upper Soc??a River Region (Southern Julian Alps, SE Europe) has been analyzed using a combination of geological mapping, glaciological modeling, and sediment dating (radiocarbon, U/Th series and Infrared Stimulated Luminescence-IRSL). Field investigations focused mainly on relatively well preserved Quaternary sequences in the Bovec Basin, an intramontane basin located SW of the Mediterranean/Black Sea divide and surrounded by mountain peaks reaching from approximately 2100 up to 2587 m a.s.l. Within the Basin we recognized two Late Quaternary sedimentary assemblages, which consist of the same facies association of diamictons, laminated lacustrine deposits and sorted fluvial sediments. Radiocarbon dating of the upper part of the lake sediments sequence (between 12790??85 and 5885??60 14C years b.p.) indicates that the younger sedimentary assemblage was deposited during the last glacial maximum and through early Holocene (Marine Isotope Stage 21, MIS 2-1). Sediment ages obtained for the older assemblage with U/Th and IRSL techniques (between 154.74??22.88 and 129.93??7.90 ka b.p. for selected samples) have large errors but both methods yield results consistent with deposition during the penultimate glacial-interglacial transition (MIS 6-5). Based on analyses of field data combined with glaciological modeling, we argue that both sediment complexes formed due to high sediment productivity spurred by paraglacial conditions with glaciers present in the uplands around the Bovec Basin but not extending down to the basin floor. Our study shows that the extent and intensity of direct glacial sedimentation by Late Quaternary glaciers in the region was previously significantly overestimated. ?? 2004 Elsevier B.V. All rights reserved.

  12. Studies on the regional feature of organic carbon in sediments off the Huanghe River Estuary waters

    Institute of Scientific and Technical Information of China (English)

    YUAN Huamao; LIU Zhigang; SONG Jinming; L(U) Xiaoxia; LI Xuegang; LINing; ZHAN Tianrong

    2004-01-01

    Organic carbon (OC) in definitely small area sediments(according to marine dimension)offthe Huanghe River Estuary is investigated in order to evaluate the feature of regional difference of physical and chemical properties in marginal sea sediments. The distributions of OC in sediments with natural grain size and the relationship with the pH,Eh,Es and Fe3+/Fe2+ are discussed. In addition, OC decomposition rates in surfacial/subsurfacial sediments are estimated. OC concentrations range from 0.26% to 1.8%(wt)in the study area. Significant differences in OC content and in horizontal distribution as well as various trends in surfacial/subsurfacial sediments exhibit the feature of regional difference remarkably in marginal sea sediments. The complicated distribution of OC in surface sediments is due to the influence of bacterial activity and abundance, bioturbation of benthos and physical disturbance. The OC decomposition rate constant in surfacial/subsurfacial sediments ranges from 0.009 7 to 0.076 a-1 and the relatively high values may be mainly related to bacteria that are mainly responsible for OC mineralization;meio-and macrofauna affect OC degradation both directly, through feeding on it, and indirectly through bioturbation and at the same time coarse sediments are also disadvantageous to OC preservation. In almost all the middle and bottom sediments the contents of Ocdecrease with the increase of deposition depth, which indicates that mineralization of OC in the middle and bottom sediments has occurred via processes like SO2-4 reduction and Fe-oxide reduction.

  13. River water quality in the northern sugarcane-producing regions of ...

    African Journals Online (AJOL)

    2011-02-16

    Feb 16, 2011 ... 1South African Sugarcane Research Institute, Private Bag X02, Mount ... Increasing demand for and use of water resources in these catchments has led to .... is located within the 50 000 km2 Inkomati River Basin, of ...... in river water pH reflecting the acidifying effect of acid mine ... First flush phenomenon,.

  14. Simulation of Regional Ground-Water Flow in the Suwannee River Basin, Northern Florida and Southern Georgia

    Science.gov (United States)

    Planert, Michael

    2007-01-01

    The Suwannee River Basin covers a total of nearly 9,950 square miles in north-central Florida and southern Georgia. In Florida, the Suwannee River Basin accounts for 4,250 square miles of north-central Florida. Evaluating the impacts of increased development in the Suwannee River Basin requires a quantitative understanding of the boundary conditions, hydrogeologic framework and hydraulic properties of the Floridan aquifer system, and the dynamics of water exchanges between the Suwannee River and its tributaries and the Floridan aquifer system. Major rivers within the Suwannee River Basin are the Suwannee, Santa Fe, Alapaha, and Withlacoochee. Four rivers west of the Suwannee River are the Aucilla, the Econfina, the Fenholloway, and the Steinhatchee; all drain to the Gulf of Mexico. Perhaps the most notable aspect of the surface-water hydrology of the study area is that large areas east of the Suwannee River are devoid of channelized, surface drainage; consequently, most of the drainage occurs through the subsurface. The ground-water flow system underlying the study area plays a critical role in the overall hydrology of this region of Florida because of the dominance of subsurface drain-age, and because ground-water flow sustains the flow of the rivers and springs. Three principal hydrogeologic units are present in the study area: the surficial aquifer system, the intermediate aquifer system, and the Floridan aquifer system. The surficial aquifer system principally consists of unconsoli-dated to poorly indurated siliciclastic deposits. The intermediate aquifer system, which contains the intermediate confining unit, lies below the surficial aquifer system (where present), and generally consists of fine-grained, uncon-solidated deposits of quartz sand, silt, and clay with interbedded limestone of Miocene age. Regionally, the intermediate aquifer system and intermediate con-fining unit act as a confining unit that restricts the exchange of water between the over

  15. An ECOMAG-based Regional Hydrological Model for the Mackenzie River basin

    Science.gov (United States)

    Motovilov, Yury; Kalugin, Andrey; Gelfan, Alexander

    2017-04-01

    A physically-based distributed model of runoff generation has been developed for the Mackenzie River basin (the catchment area is 1 660 000 km2). The model is based on the ECOMAG (ECOlogical Model for Applied Geophysics) hydrological modeling platform and describes processes of interception of rainfall/snowfall by the canopy, snow accumulation and melt, soil freezing and thawing, water infiltration into unfrozen and frozen soil, evapotranspiration, thermal and water regime of soil, overland, subsurface and ground flow, flow routing through a channel network accounting for flow regulation by lakes and reservoirs. The governing model's equations are derived from integration of the basic hydro- and thermodynamics equations of water and heat vertical transfer in snowpack, frozen/unfrozen soil, horizontal water flow under and over catchment slopes, etc. The Mackenzie basin's schematization was performed on the basis of the global DEM data (1-km resolution) from the HYDRO1K database of the U.S. Geological Survey. Most of the model parameters are physically meaningful and derived through the global datasets of the basin characteristics: FAO/IIASA Harmonized World Soil Database, USGS EROS Global Land Cover Characteristics project, etc. The 0.5ox0.5o WATCH reanalysis daily precipitation, air temperature and air humidity data were used as the model input for the period of 1971-2002. The daily discharge data provided by the Water Survey of Canada for 10 streamflow gauges, which are located at the Mackenzie River and the main tributaries (Peel River, Great Bear River, Liard River, Slave River and Athabasca River), were used for calibration (1991-2001) and validation (1971-1990) of the model. The gauges' catchment areas vary from 70600 km2 (Peel River above Fort Mopherson) to 1 660 000 km2 (Mackenzie River at Arctic Red River). The model demonstrated satisfactory performance in terms of Nash-and Sutcliffe efficiency (NSE(daily)0.60 and NSE(monthly)0.70) and percent bias

  16. Regional variability in dust-on-snow processes and impacts in the Upper Colorado River Basin

    Science.gov (United States)

    Skiles, S. McKenzie; Painter, Thomas H.; Belnap, Jayne; Holland, Lacey; Reynolds, Richard; Goldstein, Harland; Lin, J.

    2015-01-01

    Dust deposition onto mountain snow cover in the Upper Colorado River Basin frequently occurs in the spring when wind speeds and dust emission peaks on the nearby Colorado Plateau. Dust loading has increased since the intensive settlement in the western USA in the mid 1880s. The effects of dust-on-snow have been well studied at Senator Beck Basin Study Area (SBBSA) in the San Juan Mountains, CO, the first high-altitude area of contact for predominantly southwesterly winds transporting dust from the southern Colorado Plateau. To capture variability in dust transport from the broader Colorado Plateau and dust deposition across a larger area of the Colorado River water sources, an additional study plot was established in 2009 on Grand Mesa, 150 km to the north of SBBSA in west central, CO. Here, we compare the 4-year (2010–2013) dust source, deposition, and radiative forcing records at Grand Mesa Study Plot (GMSP) and Swamp Angel Study Plot (SASP), SBBSA's subalpine study plot. The study plots have similar site elevations/environments and differ mainly in the amount of dust deposited and ensuing impacts. At SASP, end of year dust concentrations ranged from 0.83 mg g−1 to 4.80 mg g−1, and daily mean spring dust radiative forcing ranged from 50–65 W m−2, advancing melt by 24–49 days. At GMSP, which received 1.0 mg g−1 less dust per season on average, spring radiative forcings of 32–50 W m−2 advanced melt by 15–30 days. Remote sensing imagery showed that observed dust events were frequently associated with dust emission from the southern Colorado Plateau. Dust from these sources generally passed south of GMSP, and back trajectory footprints modelled for observed dust events were commonly more westerly and northerly for GMSP relative to SASP. These factors suggest that although the southern Colorado Plateau contains important dust sources, dust contributions from other dust sources contribute to dust loading in this region

  17. Modelling and Analysis of Hydrodynamics and Water Quality for Rivers in the Northern Cold Region of China

    Directory of Open Access Journals (Sweden)

    Gula Tang

    2016-04-01

    Full Text Available In this study, the Mudan River, which is the most typical river in the northern cold region of China was selected as the research object; Environmental Fluid Dynamics Code (EFDC was adopted to construct a new two-dimensional water quality model for the urban sections of the Mudan River, and concentrations of CODCr and NH3N during ice-covered and open-water periods were simulated and analyzed. Results indicated that roughness coefficient and comprehensive pollutant decay rate were significantly different in those periods. To be specific, the roughness coefficient in the ice-covered period was larger than that of the open-water period, while the decay rate within the former period was smaller than that in the latter. In addition, according to the analysis of the simulated results, the main reasons for the decay rate reduction during the ice-covered period are temperature drop, upstream inflow decrease and ice layer cover; among them, ice sheet is the major contributor of roughness increase. These aspects were discussed in more detail in this work. The model could be generalized to hydrodynamic water quality process simulation researches on rivers in other cold regions as well.

  18. Modelling and Analysis of Hydrodynamics and Water Quality for Rivers in the Northern Cold Region of China

    Science.gov (United States)

    Tang, Gula; Zhu, Yunqiang; Wu, Guozheng; Li, Jing; Li, Zhao-Liang; Sun, Jiulin

    2016-01-01

    In this study, the Mudan River, which is the most typical river in the northern cold region of China was selected as the research object; Environmental Fluid Dynamics Code (EFDC) was adopted to construct a new two-dimensional water quality model for the urban sections of the Mudan River, and concentrations of CODCr and NH3N during ice-covered and open-water periods were simulated and analyzed. Results indicated that roughness coefficient and comprehensive pollutant decay rate were significantly different in those periods. To be specific, the roughness coefficient in the ice-covered period was larger than that of the open-water period, while the decay rate within the former period was smaller than that in the latter. In addition, according to the analysis of the simulated results, the main reasons for the decay rate reduction during the ice-covered period are temperature drop, upstream inflow decrease and ice layer cover; among them, ice sheet is the major contributor of roughness increase. These aspects were discussed in more detail in this work. The model could be generalized to hydrodynamic water quality process simulation researches on rivers in other cold regions as well. PMID:27070631

  19. Simulation of regional-scale groundwater flow in the Azul River basin, Buenos Aires Province, Argentina

    Science.gov (United States)

    Varni, Marcelo R.; Usunoff, Eduardo J.

    A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface

  20. Late Pleistocene and Recent geology of the Housatonic River region in northwestern Connecticut

    Science.gov (United States)

    Kelley, George C.

    1977-01-01

    dominant control factors for ice flow during late phases of deglaciation and ultimately initiated marginal stagnation zones. Late Wisconsin deglaciation evolved in three stages. First, the active ice margin receded rapidly northwestward across, and almost transverse to, the upland ridge crests in response to factors of both backwasting and downwasting. Second, local terrain relief restricted active ice flow, initiated stagnation, diverted melt-water flow and controlled deposition of small active ice-marginal deposits on the northwest slopes of ridges. Third, melting and thinning of stagnant ice tongues in valleys with ice surfaces which were low gradient and southward-sloping caused rapid northward recession of the stagnant ice margin. Sequences of related outwash deposits have been correlated with inferred ice-marginal, recessional positions. In this region, the zone of stagnant ice distal to active ice ranged from 6 to 15 miles in average width. Lacustrine sediments accumulated as stagnant ice blocks melted in isolated basins and other depressions where through-flowing melt-water drainage was restricted or absent. The paucity of ice-contact and outwash deposits in the isolated basins indicates that little entrained debris was present in the stagnant ice. Prograding outwash along the Housatonic River and other major drainage routes infilled glacially overdeepened underlying lacustrine sediments sand and gravel. rock basins and buried beneath upward-coarsening Upland bogs, which have developed postglacially, contain as much as 22 feet of organic material mixed with silt and clay. An age of 12,750 ? 230 years B.P. was determined for materials immediately above three feet of older organic-rich clay layers. This dated material correlates with the upper part of the pollen T zone reported elsewhere in Connecticut and New York.

  1. River effect” of radiofrequency ablation on relevant regional hepatocytes in living swine liver: a preliminary pathological study

    Directory of Open Access Journals (Sweden)

    Kai JIANG

    2013-05-01

    Full Text Available Objective  To establish the animal model of radiofrequency ablation (RFA on living swine liver, and observe the pathologic changes caused by the "river effect (RE"of RFA on relevant regional hepatocytes. Methods  Three target segments of liver of each of 6 Guangxi BA-MA mini pigs were selected for ablation. Under the guidance of sonography, the tip of RFA electrode was inserted into the liver close to segmental outflow vessel, and every ablated point was heated for 6 minutes. Pathological changes of relevant downstream region along portal vein and hepatic artery were observed under microscope after RFA. Results  The ablated region of the liver was oblong in shape with outer diameter of 2.2±1.1cm on gross inspection. Thermal damage (e.g. obvious dilated blood sinuses, with abundant inflammatory cell infiltration in portal vein region and necrosis of hepatocytes, etc. was observed in downstream region of the relevant portal vein under microscope after RFA. However, liver tissue in adjacent area around the vessel was intact, and no obvious thermal damage was found. Conclusion  The "river effect" during RFA for liver tissue may lead to thermal damage to hepatocytes along the downstream region of the regional portal vein, and this effect decreases gradually toward the surface of liver segment.

  2. Geophysical Characterization for a CO2 Sequestration Potential in the Ohio River Valley Region

    Science.gov (United States)

    Gupta, N.; Jagucki, P.; Meggyesy, D.; Janosy, R.; Sminchak, J.; Ramakrishan, T.; Boyd, A.

    2003-12-01

    A site at the American Electric Power's (AEP) Mountaineer Power Plant, WV in the Ohio River Valley in the Midwestern U.S., a region with the economy heavily dependent on fossil fuels, such as coal, oil, and gas, is being evaluated to determine the potential for geologic sequestration. The project is supported by the U.S. Department of Energy, Battelle, AEP, BP, The Ohio Air Quality Development Office, and Schlumberger. The major objective of the current phase is to characterize the reservoir at the plant site. Future decisions with regard to CO2 injection will be subject to the evaluated reservoir properties. The effort includes acquisition of 2-dimensional seismic data, assessment of regional geology, drilling to PreCambrian rocks and formation analysis and testing in a 2,800 meters deep well, reservoir simulations, risk assessment, and stakeholder outreach. The test well reached total depth in summer 2003. Wireline logging and reservoir testing was performed for each section of the borehole, including extensive tests in the lowermost 885 meters to estimate formation properties and pressure gradients. The logs included gamma-ray, neutron and density, and array resistivity, magnetic resonance relaxation for permeability information, elemental composition via capture spectroscopy, and resistivity based formation image. The seismic survey was conducted over approximately 11 miles along 2 lines: one along strike and one along dip. The results of the geophysical surveys combined with the field observations provide an integrated assessment of the major injection parameters for the two main injection reservoirs of interest, the Rose Run Formation and the Lower Maryville formation. In addition, the properties of the potential caprock formations overlying the candidate injection zones were also determined. The results of this characterization will be presented with emphasis on geophysical testing and seismic survey. These results are also being used to conduct reservoir

  3. Assessment of water quality and toxicity of polluted Rivers Fez and Sebou in the region of Fez (Morocco).

    Science.gov (United States)

    Koukal, B; Dominik, J; Vignati, D; Arpagaus, P; Santiago, S; Ouddane, B; Benaabidate, L

    2004-09-01

    Water quality assessment in the region of Fez based on the physicochemical and ecotoxicological investigations is presented. The results indicate that sites located close to the most urbanized and industrialized areas are severely impaired. The major water quality problems are: low dissolved oxygen (DO), high turbidity, organic matter and ammonia contents, severe chromium and copper pollution and high acute and chronic toxicity. This results in the loss of the aquatic life which is still flourishing in the Fez River upstream from the Fez Medina. Remote sites downstream show signs of physicochemical recovery. However, even there, bioassays showed significant acute and chronic toxicity. Well water in the region of Fez has moderately poor water quality with nitrate and metal enrichments. Use of water for drinking or for agriculture from the rivers or from some wells without treatment may expose the population to health risk.

  4. Watershed regulation and local action: analysis of the Senegal River watershed management by a regional organisation and public participation

    Directory of Open Access Journals (Sweden)

    A. M. Sène

    2007-06-01

    Full Text Available Several social scientists have dealt with the usefulness of a participative approach in development plans. The call for sustainable development has increased the focus on this type of approach in a very classical way, which is the case for the creation of new water tanks. Most of these scientists have also pinpointed the major difficulties and failures faced during the execution of this new approach in developing countries. This study is a concrete example which underlines the lack of this type of approach as far as water management in the Senegal River is concerned, mainly in relation to watershed. We base our study on the analysis and criticism of the regional organization OMVS (Organization for the Development of the Senegal River which is in charge of water management in the Senegal River. The results of the study can, therefore, be summed up as follows: (i An on-site direct observation, individual interviews, group discussion and information analysis point out the lack of participation of local people in water management in the Senegal River and, in general, the harmful socio-economic impacts resulting from it. (ii The reasons for this lack of participative approach are mainly due to the model set up by the OMVS in terms of water management in the Senegal River, a model that has excluded or tackled in a very light way the issue of public participation in decision-making through out its juridical and regulation instruments. (iii Elements of consideration on some measures, which could possibly improve the level of participation of local people in river water management.

  5. Parasitism of the isopod Artystone trysibia in the fish Chaetostoma dermorhynchum from the Tena River (Amazonian region, Ecuador).

    Science.gov (United States)

    Junoy, Juan

    2016-01-01

    The isopod Artystone trysibia Schioedte, 1866 is described by using a collection of specimens that were found parasitizing loricariid fish Chaetostoma dermorhynchum Boulenger, 1887 in the Tena River (Napo province, Ecuador, Amazonian region). Additionally to freshly collected specimens, complementary data of the parasite was obtained from preserved fishes at Ecuadorian museums. This is the first record of A. trysibia in Ecuador, and the most upstream location for the species. The new host fish, Chaetostoma dermorhynchum, is used locally as food.

  6. Impacts of Climate Change on Stream Flow in the Upper Mississippi River Basin: A Regional Climate Model Perspective, The

    OpenAIRE

    Manoj Jha; Zaitao Pan; Takle, Eugene S.; Roy Gu

    2003-01-01

    We evaluate the impact of climate change on stream flow in the Upper Mississippi River Basin (UMRB) by using a regional climate model (RCM) coupled with a hydrologic model, the Soil and Water Assessment Tool (SWAT). The SWAT model was calibrated and validated against measured stream flow data using observed weather data and inputs from the Environmental Protection Agency's BASINS (Better Assessment Science Integrating Point and Nonpoint Sources) geographical information/database system. The c...

  7. Investigating the Impacts of Landuse-landcover (LULC) Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    OpenAIRE

    Hongyan Xi; Yuanzhi Zhang; Yunpeng Wang; Yufei Wang

    2009-01-01

    Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE) is of great concern to the local community. Due to great landuse-landcover (LULC) changes with rapid industrialization and urbanization in the Pearl River Delta (PRD) region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, ...

  8. Variation Characteristics of the Large-scale Frost in East Region of the Yellow River of Gansu in Recent 40 Years

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective]The research aimed to study variation characteristics of large-scale frost in the east region of the Yellow River of Gansu in recent 40 years.[Method]Based on daily minimum temperature data at 15 meteorological stations over the east region of the Yellow River of Gansu from 1969 to 2008,according to common climatic statistical index of the frost,variation characteristics of the large-scale frost and continuous frost in the east region of the Yellow River of Gansu in recent 40 years were studied.[...

  9. Sources of excess urban carbonaceous aerosol in the Pearl River Delta Region, China

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, M.; Wang, F.; Hagler, G.S.W.; Hou, X.M.; Bergin, M.; Cheng, Y.A.; Salmon, L.G.; Schauer, J.J.; Louie, P.K.K.; Zeng, L.M.; Zhang, Y.H. [Peking University, Beijing (China). College of Environmental Science & Engineering

    2011-02-15

    Carbonaceous aerosol is one of the important constituents of fine particulate matter (PM2.5) in southern China, including the Pearl River Delta (PRD) region and Hong Kong (HK). During the study period (October and December of 2002, and March and June of 2003), the monthly average organic carbon (OC) ranged from 3.52 to 7.87 {mu} g m{sup -3} in Hong Kong and 4.14-20.19 {mu} g m{sup -3} in the PRD from simultaneous measurements at three sites in HK and four sites in the PRO. Compared to the PRD, the spatial distribution of carbonaceous aerosol in Hong Kong was relatively homogeneous. Sources contributing to excess OC in the PRO were examined, which is the difference between OC concentrations measured at the PRD sites to the average level in Hong Kong. Eight primary sources contributing to excess OC were identified with chemical mass balance modeling in a combination with molecular markers analyzed by gas chromatography/mass spectrometry. Excess OC at Guangzhou, the capital city of Guangdong province, was consistently high, ranging from 9.77 to 13.6 {mu} g m{sup -3}. Four primary sources including gasoline engine exhaust, diesel engine exhaust, biomass burning, and coal combustion accounted for more than 50% of excess OC in the PRD, especially in December (up to 76%). Mobile source emissions alone can contribute about 30% of excess OC. The unexplained or other excess OC was the highest at the rural site, but in general less than 20% at other sites. The coal combustion source contribution was unique in that it exhibited relatively homogeneous spatial distribution, indicating it was still an important source of carbonaceous aerosol in the PRD (17% of excess OC) during the study period.

  10. Heavy Metal Pollution in a Soil-Rice System in the Yangtze River Region of China

    Directory of Open Access Journals (Sweden)

    Zhouping Liu

    2015-12-01

    Full Text Available Heavy metals are regarded as toxic trace elements in the environment. Heavy metal pollution in soil or rice grains is of increasing concern. In this study, 101 pairs of soil and rice samples were collected from the major rice-producing areas along the Yangtze River in China. The soil properties and heavy metal (i.e., Cd, Hg, Pb and Cr concentrations in the soil and rice grains were analyzed to evaluate the heavy metal accumulation characteristics of the soil-rice systems. The results showed that the Cd, Hg, Pb and Cr concentrations in the soil ranged from 0.10 to 4.64, 0.01 to 1.46, 7.64 to 127.56, and 13.52 to 231.02 mg·kg−1, respectively. Approximately 37%, 16%, 60% and 70% of the rice grain samples were polluted by Cd, Hg, Pb, and Cr, respectively. The degree of heavy metal contamination in the soil-rice systems exhibited a regional variation. The interactions among the heavy metal elements may also influence the migration and accumulation of heavy metals in soil or paddy rice. The accumulation of heavy metals in soil and rice grains is related to a certain extent to the pH and soil organic matter (SOM. This study provides useful information regarding heavy metal accumulation in soil to support the safe production of rice in China. The findings from this study also provide a robust scientific basis for risk assessments regarding ecological protection and food safety.

  11. Heavy Metal Pollution in a Soil-Rice System in the Yangtze River Region of China.

    Science.gov (United States)

    Liu, Zhouping; Zhang, Qiaofen; Han, Tiqian; Ding, Yanfei; Sun, Junwei; Wang, Feijuan; Zhu, Cheng

    2015-12-22

    Heavy metals are regarded as toxic trace elements in the environment. Heavy metal pollution in soil or rice grains is of increasing concern. In this study, 101 pairs of soil and rice samples were collected from the major rice-producing areas along the Yangtze River in China. The soil properties and heavy metal (i.e., Cd, Hg, Pb and Cr) concentrations in the soil and rice grains were analyzed to evaluate the heavy metal accumulation characteristics of the soil-rice systems. The results showed that the Cd, Hg, Pb and Cr concentrations in the soil ranged from 0.10 to 4.64, 0.01 to 1.46, 7.64 to 127.56, and 13.52 to 231.02 mg·kg(-)¹, respectively. Approximately 37%, 16%, 60% and 70% of the rice grain samples were polluted by Cd, Hg, Pb, and Cr, respectively. The degree of heavy metal contamination in the soil-rice systems exhibited a regional variation. The interactions among the heavy metal elements may also influence the migration and accumulation of heavy metals in soil or paddy rice. The accumulation of heavy metals in soil and rice grains is related to a certain extent to the pH and soil organic matter (SOM). This study provides useful information regarding heavy metal accumulation in soil to support the safe production of rice in China. The findings from this study also provide a robust scientific basis for risk assessments regarding ecological protection and food safety.

  12. Pollen flow of wheat under natural conditions in the Huanghuai River Wheat Region, China.

    Science.gov (United States)

    Sun, Ai-Qing; Zhang, Chun-Qing; Wu, Cheng-Lai; Gao, Qing-Rong

    2015-01-01

    The transgenic pollen spread is the main pathway of transgenic plant gene flow. The maximum distance of pollen dispersal (horizontal), the spatial dynamics of pollen movement (vertical), and the patterns of pollen dispersal are important considerations in biosafety assessments of genetically modified crops. To evaluate wheat (Triticum aestivum) pollen dispersal, we measured the pollen suspension velocity and analyzed pollen dispersal patterns under natural conditions in the Huanghuai River wheat-growing region in 2009. The pollen suspension velocity was 0.3-0.4 m/s. The highest pollen densities were detected in the north, northwest, and south of the pollen source. Pollen was dispersed over distances greater than 245 m in the northwest and northeast directions. At the pollen source center, pollen density decreased with increasing vertical height. In the north of the pollen source, the pollen density from 65 m to 225 m showed a wave-mode decrease with increasing height. The horizontal transport of pollen over longer distances fitted polynomial equations. In the north, the pollen density was highest at 45 m from the pollen source, and decreased with increasing distance. In the northwest, the pollen density showed a double-peak trend. In the northeast, pollen density was highest from 45 m to 125 m from the source. Wind speeds greater than the pollen suspension velocity and the duration of continuous gusts were the main factors affecting pollen dispersal. This information will be useful for determining the spatial isolation distances for hybrid seed production and for the commercial production of transgenic wheat.

  13. Deformation Rates in the Snake River Plain and Adjacent Basin and Range Regions Based on GPS Measurements

    Science.gov (United States)

    Payne, S. J.; McCaffrey, R.; King, R. W.; Kattenhorn, S. A.

    2012-12-01

    We estimate horizontal velocities for 405 sites using Global Positioning System (GPS) phase data collected from 1994 to 2010 within the Northern Basin and Range Province, U.S.A. The velocities reveal a slowly-deforming region within the Snake River Plain in Idaho and Owyhee-Oregon Plateau in Oregon separated from the actively extending adjacent Basin and Range regions by shear. Our results show a NE-oriented extensional strain rate of 5.6 ± 0.7 nanostrain/yr in the Centennial Tectonic Belt and an ~E-oriented extensional strain rate of 3.5 ± 0.2 nanostrain/yr in the Great Basin. These extensional rates contrast with the very low strain rate within the 125 km x 650 km region of the Snake River Plain and Owyhee-Oregon Plateau which is not distinguishable from zero (-0.1 ± 0.4 x nanostrain/yr). Inversions of Snake River Plain velocities with dike-opening models indicate that rapid extension by dike intrusion in volcanic rift zones, as previously hypothesized, is not currently occurring. GPS data also disclose that rapid extension in the surrounding regions adjacent to the slowly-deforming region of the Snake River Plain drives shear between them. We estimate right-lateral shear with slip rates of 0.3-1.5 mm/yr along the northwestern boundary adjacent to the Centennial Tectonic Belt and left-lateral oblique extension with slip rates of 0.5-1.5 mm/yr along the southeastern boundary adjacent to the Intermountain Seismic Belt. The fastest lateral shearing evident in the GPS occurs near the Yellowstone Plateau where earthquakes with right-lateral strike-slip focal mechanisms are within a NE-trending zone of seismicity. The regional velocity gradients are best fit by nearby poles of rotation for the Centennial Tectonic Belt, Snake River Plain, Owyhee-Oregon Plateau, and eastern Oregon, indicating that clockwise rotation is not locally driven by Yellowstone hotspot volcanism, but instead by extension to the south across the Wasatch fault possibly due to gravitational

  14. Environmental Assessment for the construction and operation of the Three Rivers Solid Waste Authority regional waste management center at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    This Environmental Assessment (EA) has been prepared by the US Department of Energy (DOE) to assess the potential environmental impacts associated with the construction and operation of a landfill and technology center for regionally-generated municipal solid waste at the Savannah River Site (SRS) near Aiken, South Carolina. The facility would serve the municipal solid waste disposal needs for SRS and at least nine of the surrounding counties who currently comprise the Three Rivers Solid Waste Authority (TRSWA). Additional counties could become included in the proposed action at some future date. Current Federal and state requirements do not afford individual counties and municipalities within the region encompassing SRS the ability to efficiently or economically operate modern waste management facilities. In addition, consolidation of regional municipal solid waste at one location would have the benefit of reducing the duplicity of environmental consequences associated with the construction and operation of county-level facilities. The option to seek a combined disposal and technology development facility based on a regionally-cooperative effort was selected as a viable alternative to the existing individual SRS or county disposal activities. This document was prepared in compliance with the National Environmental Policy Act (NEPA) of 1969, as amended, the requirements of the Council on Environmental Quality Regulations for Implementing NEPA (40 CFR Part 1021). NEPA requires the assessment of environmental consequences of Federal actions that may affect the quality of the human environment. Based on the potential for impacts described for impacts described herein, DOE will either publish a Finding of No Significant Impact or prepare an environmental impact statement (EIS).

  15. Regional water table (2014) in the Mojave River and Morongo Groundwater Basins, southwestern Mojave Desert, California

    Science.gov (United States)

    Teague, Nick F.; Stamos, Christina L.; House, Sally F.; Clark, Dennis A.

    2016-06-28

    2014 Water TableData for static water levels measured in about 610 wells during March–April 2014 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct this regional water-table map. This map shows the elevation of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater basins. Water levels recorded by the USGS and MWA staff were measured and compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). Water-level data submitted by cooperating local water districts were collected by using procedures established by the corresponding agency and were compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). All data were compared to historical data for qualityassurance purposes. Water-level contours from the 2012 water-level map (Teague and others, 2014) were used as a guide to interpret and shape the 2014 water-level contours in areas where 2014 water-level data were not available; these contours are shown as dashed (approximate) on this water-table map. Water-level data and contours are shown for the Warren subbasin in the Morongo groundwater basin in greater detail on inset A.The water table is the surface at which the fluid pressure in the pores of a porous medium is exactly atmospheric (Freeze and Cherry, 1979). The water table is defined by the level of the water surface in wells that just penetrate the top of the water body (Lohman, 1972). The water-level measurements used for the water-level contour maps are from wells that have more than one perforated interval in the saturated zone of the groundwater basins. Although these wells can have different perforated zones, the measured water levels from the zones were within about 10 feet (ft) and, therefore

  16. Light Absorption of Brown Carbon Aerosol in the Pearl River Delta Region of China

    Science.gov (United States)

    Huang, X.

    2015-12-01

    X.F. Huang, J.F. Yuan, L.M. Cao, J. Cui, C.N. Huang, Z.J. Lan and L.Y. He Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, ChinaCorresponding author. Tel.: +86 755 26032532; fax: +86 755 26035332. E-mail address: huangxf@pku.edu.cn (X. F. Huang). Abstract: The strong spectral dependence of light absorption of brown carbon (BrC) aerosol has been recognized in recent decades. The Absorption Angstrom Exponent (AAE) of ambient aerosol was widely used in previous studies to attribute light absorption of brown carbon at shorter wavelengths, with a theoretical assumption that the AAE of black carbon (BC) aerosol equals to unit. In this study, the AAE method was improved by statistical extrapolation based on ambient measurements in the polluted seasons in typical urban and rural areas in the Pearl River Delta (PRD) region of China. A three-wavelength photoacoustic soot spectrometer (PASS-3) and an aerosol mass spectrometer (AMS) were used to explore the relationship between the ambient measured AAE and the ratio of organic aerosol to BC aerosol, in order to extract the more realistic AAE by pure BC aerosol, which were found to be 0.86, 0.82 and 1.02 at 405nm and 0.70, 0.71, and 0.86 at 532nm in the campaigns of urban-winter, urban-fall, and rural-fall, respectively. Roadway tunnel experiment results further supported the effectiveness of the obtained AAE for pure BC aerosol. In addition, biomass burning experiments proved higher spectral dependence of more-BrC environment and further verified the reliability of the instruments' response. Then, the average light absorption contribution of BrC aerosol was calculated to be 11.7, 6.3 and 12.1% (with total relative uncertainty of 7.5, 6.9 and 10.0%) at 405nm and 10.0, 4.1 and 5.5% (with total relative uncertainty of 6.5, 8.6 and 15.4%) at 532nm of the three campaigns, respectively. These results indicate that the

  17. Assessing regional climate simulations of the last 30 years (1982-2012) over Ganges-Brahmaputra-Meghna River Basin

    Science.gov (United States)

    Khandu; Awange, Joseph L.; Anyah, Richard; Kuhn, Michael; Fukuda, Yoichi

    2016-11-01

    The Ganges-Brahmaputra-Meghna (GBM) River Basin presents a spatially diverse hydrological regime due to it's complex topography and escalating demand for freshwater resources. This presents a big challenge in applying the current state-of-the-art regional climate models (RCMs) for climate change impact studies in the GBM River Basin. In this study, several RCM simulations generated by RegCM4.4 and PRECIS are assessed for their seasonal and interannual variations, onset/withdrawal of the Indian monsoon, and long-term trends in precipitation and temperature from 1982 to 2012. The results indicate that in general, RegCM4.4 and PRECIS simulations appear to reasonably reproduce the mean seasonal distribution of precipitation and temperature across the GBM River Basin, although the two RCMs are integrated over a different domain size. On average, the RegCM4.4 simulations overestimate monsoon precipitation by {˜ }26 and {˜ }5% in the Ganges and Brahmaputra-Meghna River Basin, respectively, while PRECIS simulations underestimate (overestimate) the same by {˜ }7% ({˜ }16% ). Both RegCM4.4 and PRECIS simulations indicate an intense cold bias (up to 10°C) in the Himalayas, and are generally stronger in the RegCM4.4 simulations. Additionally, they tend to produce high precipitation between April and May in the Ganges (RegCM4.4 simulations) and Brahmaputra-Meghna (PRECIS simulations) River Basins, resulting in early onset of the Indian monsoon in the Ganges River Basin. PRECIS simulations exhibit a delayed monsoon withdrawal in the Brahmaputra-Meghna River Basin. Despite large spatial variations in onset and withdrawal periods across the GBM River Basin, the basin-averaged results agree reasonably well with the observed periods. Although global climate model (GCM) driven simulations are generally poor in representing the interannual variability of precipitation and winter temperature variations, they tend to agree well with observed precipitation anomalies when driven by

  18. Environmental surveillance monitoring in the Alligator Rivers Region. Report for the six months period ending 30 September 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This report outlines the activities of the Northern Territory Supervising Authorities in meeting their responsibilities for environmental management and surveillance, occupational safety, relating to uranium mining and environment protection in the Alligator Rivers Region. Environmental monitoring was carried out at the Nabarlek Mine, which site has now been rehabilitated and revegetated, and at Ranger, the only mine currently operating in the region. Other uranium projects such as Jabiluka and Koongarra have been delayed due to the former Commonwealth Government`s `three mines policy`. 4 tabs., 10 figs.

  19. Inferior Rectus Transposition: A Novel Procedure for Abducens Palsy.

    Science.gov (United States)

    Velez, Federico G; Chang, Melinda Y; Pineles, Stacy L

    2017-05-01

    Superior rectus transposition has been popularized for the treatment of abduction deficiencies. Potential complications include induced vertical deviation and torsion. A new procedure, the inferior rectus transposition (IRT), may be similarly beneficial for patients at risk for postoperative vertical deviation or incyclotropia. The purpose of this study is to describe the outcomes of patients undergoing IRT. Prospective, interventional case series. Five patients in an academic pediatric ophthalmology and strabismus practice with a complete lateral rectus palsy who underwent IRT were studied. Changes in anomalous head posture, ocular rotations, ocular alignment, and torsion preoperatively to postoperatively were compared. The patients ranged in age from 19-89 years. There was a significant correction in the angle of esotropia (ET) from 39±17Δ (14-55Δ) to 12 ± 9.8Δ (0-22Δ) postoperatively (P = .02). Two of 5 patients had preoperative hypertropia of the affected eye (1.4 ± 2.2Δ; range, 2-5Δ). One of those had no vertical deviation postoperatively and 1 patient resulted in 2Δ hypotropia. One patient without vertical misalignment preoperatively developed a small postoperative vertical deviation. Torticollis significantly improved from 31.4 ± 11.6° to 5 ± 5.8° (P = .004). All patients improved abduction, with a mean of -4.4 ± 0.5 preoperatively to -3.4 ± 0.9 postoperatively (P = .07). Initial postoperative follow-up in patients with abducens palsy undergoing IRT shows a significant improvement in ocular alignment and torticollis. In patients with preoperative hypertropia, IRT resulted in a downward shifting effect on the operated eye. IRT may be a beneficial procedure for patients with preoperative hypertropia or intorsion requiring transposition procedures. Future studies with larger populations and longer durations of follow-up will be required before this procedure can be recommended. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Large-Scale Transposition Mutagenesis of Streptomyces coelicolor Identifies Hundreds of Genes Influencing Antibiotic Biosynthesis.

    Science.gov (United States)

    Xu, Zhong; Wang, Yemin; Chater, Keith F; Ou, Hong-Yu; Xu, H Howard; Deng, Zixin; Tao, Meifeng

    2017-03-15

    Gram-positive Streptomyces bacteria produce thousands of bioactive secondary metabolites, including antibiotics. To systematically investigate genes affecting secondary metabolism, we developed a hyperactive transposase-based Tn5 transposition system and employed it to mutagenize the model species Streptomyces coelicolor, leading to the identification of 51,443 transposition insertions. These insertions were distributed randomly along the chromosome except for some preferred regions associated with relatively low GC content in the chromosomal core. The base composition of the insertion site and its flanking sequences compiled from the 51,443 insertions implied a 19-bp expanded target site surrounding the insertion site, with a slight nucleic acid base preference in some positions, suggesting a relative randomness of Tn5 transposition targeting in the high-GC Streptomyces genome. From the mutagenesis library, 724 mutants involving 365 genes had altered levels of production of the tripyrrole antibiotic undecylprodigiosin (RED), including 17 genes in the RED biosynthetic gene cluster. Genetic complementation revealed that most of the insertions (more than two-thirds) were responsible for the changed antibiotic production. Genes associated with branched-chain amino acid biosynthesis, DNA metabolism, and protein modification affected RED production, and genes involved in signaling, stress, and transcriptional regulation were overrepresented. Some insertions caused dramatic changes in RED production, identifying future targets for strain improvement.IMPORTANCE High-GC Gram-positive streptomycetes and related actinomycetes have provided more than 100 clinical drugs used as antibiotics, immunosuppressants, and antitumor drugs. Their genomes harbor biosynthetic genes for many more unknown compounds with potential as future drugs. Here we developed a useful genome-wide mutagenesis tool based on the transposon Tn5 for the study of secondary metabolism and its regulation

  1. Impacts of climate change on glacial water resources and hydrological cycles in the Yangtze River source region,the Qinghai-Tibetan Plateau,China:A Progress Report

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Yangtze River Source Region has an area of 137,704 km2.Its mean annual runoff of 12.52 billion m3,which was recorded by the Chumda Hydrological Station in 1961-2000,accounts for only 0.13 percent of the Yangtze River’s total annual streamflow.The extensive rivers,lakes,wetlands,glaciers,snow fields,and permafrost of the Yangtze River Source Region,as well as the region’s vast alpine grasslands,play a critical role in storing and regulating the flow of water not only in the upper Yangtze River watershed of Qinghai,Sichuan,the Tibet Autonomous Region (TAR) (Tibet) and Yunnan,but also throughout the entire lower Yangtze River basin.Climate change has been the dominant factor in recent fluctuation in the volume of the Yangtze River Source Region’s glacier resources.The Chumda Hydrological Station on the lower Tongtian River has registered a mean annual glacial meltwater of 1.13 billion m3 for the period 1961-2000,makes up 9 percent of the total annual runoff.Glacial meltwater makes up a significant percentage of streamflow in the Yangtze River Source Region,the major rivers of the upper Yangtze River Source Region:the Togto,Dam Chu,Garchu,and Bi Chu (Bu Chu) rivers all originate at large glaciers along the Tanggula Range.Glaciers in the Yangtze River Source Region are typical continental-type glaciers with most glacial meltwater flow occurring June-August;the close correlation between June-August river flows and temperature illustrates the important role of glacial meltwater in feeding rivers.Glaciers in the source region have undergone a long period of rapid ablation beginning in 1993.Examination of flow and temperature data for the 1961-2000 period shows that the annual melting period for glacial ice,snow,and frozen ground in the Yangtze River Source Region now begins earlier because of increasing spring temperatures,resulting in the reduction of summer flood season peak runoffs;meanwhile,increased rates of glacier ablation have resulted in more uneven

  2. Surface water characterization of three rivers in the lead/zinc mining region of northeastern Macedonia.

    Science.gov (United States)

    Ramani, Sheriban; Dragun, Zrinka; Kapetanović, Damir; Kostov, Vasil; Jordanova, Maja; Erk, Marijana; Hajrulai-Musliu, Zehra

    2014-05-01

    Mine waste is recognized as being one of the most serious threats for freshwater ecosystems, and it still represents one of the greatest environmental concerns in Macedonia. The aim of our investigation was to obtain an in-depth understanding of mining influence on freshwater systems from water contamination to effects on aquatic organisms. In this study, we assessed the impact of active lead (Pb)/zinc (Zn) mines Zletovo and Toranica on the water quality of three rivers in northeastern Macedonia (Bregalnica, Zletovska, and Kriva rivers) based on data collected in spring and autumn of 2012. The Bregalnica River, near Shtip, was characterized mainly by weak contamination with arsenic, barium, iron, molybdenum, titanium, uranium, vanadium, nitrate, and phosphate, as well as critical faecal pollution, which alltogether could be connected to agricultural activities; however, an impact of the mines was not observed. Contrary, both the Zletovska and Kriva rivers showed a clear impact of Pb/Zn mines on water quality. In the Zletovska River, increased concentrations of cadmium (Cd), cobalt, cesium, copper, lithium, manganese (Mn), nickel, rubidium, tin, strontium, thallium, Zn, sulphates, and chlorides were found, especially in autumn (e.g., Cd 2.0 μg L(-1); Mn 2.5 mg L(-1); Zn 1.5 mg L(-1)). In the Kriva River, increased Cd (0.270 μg L(-1)) and Pb (1.85 μg L(-1)) concentrations were found only in spring, possibly due to sediment resuspension during greater water discharge. The selected sampling sites on the Bregalnica, Zletovska, and Kriva rivers were confirmed as being appropriate locations for further studies of mining waste's impact on freshwater ecosystems, the first one as a nonimpacted site and the other two as possible areas of increased exposure of aquatic organisms to metals.

  3. Maxillary canine transpositions in two brothers and one sister: associated dental anomalies and genetic basis.

    Science.gov (United States)

    Segura, Juan J; Hattab, Faiez; Ríos, Vicente

    2002-01-01

    Transposition is an uncommon dental anomaly involving positional interchange of two teeth. The maxillary canine is the tooth more frequently transposed in man. Maxillary canine-first premolar appears to be the most common type of tooth transposition, followed by maxillary canine-lateral incisor transposition. Maxillary canine transpositions are frequently associated with other dental abnormalities such as agenesis and pegshaped incisors. This report describes the presence of transposed canines in one sister and two brothers. The female showed bilateral maxillary canine-first premolar transposition with the left canine fully mesial to its neighboring first premolar, and the right canine blocked-out facially between the first and second premolar. One of the brothers showed full maxillary left canine-lateral incisor transposition. The other brother showed maxillary canine-first premolar transposition and agenesis of maxillary lateral incisors, with the left canine blocked-out facially between the first and second premolar. Findings from this case report and other previously published cases provide strong evidence that maxillary canine transpositions are a disturbance of tooth order and eruptive position resulting from genetic influences within a multifactorial inheritance model.

  4. Frequency and distance of transposition of a modified Dissociation element in transgenic tobacco

    NARCIS (Netherlands)

    Biezen, E.A. van der; Cardol, E.F.; Chung, H.Y.; Nijkamp, H.J.J.; Hille, J.

    1996-01-01

    Effective transposon tagging with the Ac/Ds system in heterologous plant species relies on the accomplishment of a potentially high transposon-induced mutation frequency. The primary parameters that determine the mutation frequency include the transposition frequency and the transposition distance.

  5. The politics of compliance : explaining the transposition of EC directives in the Netherlands

    NARCIS (Netherlands)

    Mastenbroek, Ellen

    2007-01-01

    The EU suffers from an implementation deficit. Member states often do not comply with EU policies, which in turn hampers the process of European integration. This book documents the problem with the timely transposition of EU directives. It explores the size and the causes of the transposition

  6. Facts about dextro-Transposition of the Great Arteries (d-TGA)

    Science.gov (United States)

    ... view a larger image Dextro-Transposition (pronounced DECKS-tro trans-poh-ZI-shun) of the Great Arteries ... Great Arteries (d-TGA)? Dextro-Transposition (pronounced DECKS-tro trans-poh-ZI-shun) of the Great Arteries ...

  7. Risk Assessment of Regional Irrigation Water Demand and Supply in an Arid Inland River Basin of Northwestern China

    Directory of Open Access Journals (Sweden)

    Bin Guo

    2015-09-01

    Full Text Available Irrigation water demand accounts for more than 95% of the total water use in the Kaidu-kongqi River Basin. Determination of the spatial and temporal trends in irrigation water demand is important for making sustainable and wise water management strategies in this highly water deficit region. In this study, the spatial and temporal trends in irrigation water demand as well as net crop irrigation water requirements for nine major crops during 1985–2009 were analyzed by combining the Penman-Monteith equation recommended by Food and Agriculture Organization (FAO and GIS technology. The regional water stress was also evaluated based on the total irrigation water demand and river discharge at the annual and monthly scales. The results indicated that the annual irrigation water demand in this arid region showed a significant increasing trend during the past 25 years. Total irrigation water demand increased from 14.68 × 108 m3 in 1985 to 34.15 × 108 m3 in 2009. The spatial pattern of total irrigation water demand was significantly affected by the changes in cotton growing area. Due to differences in crop planting structure, the monthly average irrigation water demands in Korla City and Yuli County amounted to the peak in July, while those in other regions reached the maximum in June. Although the annual river runoff was much larger than the irrigation water demand, there was serious water deficit during the critical water use period in May and June in some dry years. The presented study provides important information for managers and planners on sustainable use of water resources in this arid region.

  8. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Hydrologic Landscape Regions

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of Hydrologic Landscape Regions (HLR) compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and...

  9. Regional Response of Ecological Effects of Cascade Reservoirs Development within the Maotiaohe River Watershed%Regional Response of Ecological Effects of Cascade Reservoirs Development within the Maotiaohe River Watershed

    Institute of Scientific and Technical Information of China (English)

    李亦秋; 鲁春霞; 邓欧; 杨广斌

    2011-01-01

    Studying regional ecological effects of water conservancy projects plays a significant role in improving water resources use efficiency and reducing negative effects of the water conservancy projects. In this study, the authors took the environmental impact of water conservancy projects and the resulting regional response to ecosystems as a subject. Based on a cascade development concept model of ecological effects of regional response of the Maotiao River watershed, mutual contact and restraint ecosystems, including river ecosystems, terrestrial ecosystems, and human living and production systems, were analyzed and summarized according to the level order of regional response of ecological effects at the temporal scale and ecological spatial scale. A comprehensive analysis was performed on the regional response of non-ecological and ecological variables in the above-mentioned three ecosystems in the Maotiao River watershed. Regional ecological effects of water conservancy projects in the Maotiao River watershed were analyzed in terms of 1) regional response of non-ecological and ecological variables, such as hydrological regime and water quantity, water quality and water environment, and aquatic community of river ecosystems, 2) regional response of non-ecological and ecological variables, such as air quality, regional climate change, and other terrestrial vegetation and wildlife of terrestrial ecosystems, and 3) regional response of land resources, cultivated land area, and population health, etc. of human living and production systems. It was found that the watershed development has resulted in population growth, industry concentration, social development, as well as a series of irreversible ecological and environmental problems which made the contradiction between people and land more acute. Therefore, for a watershed in which the cascade development has been achieved, much effort should be made to shift the industrial structure from high energy

  10. Numerical model to quantify biogenic volatile organic compound emissions: The Pearl River Delta region as a case study.

    Science.gov (United States)

    Wang, Xuemei; Situ, Shuping; Chen, Weihua; Zheng, Junyu; Guenther, Alex; Fan, Qi; Chang, Ming

    2016-08-01

    This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.

  11. River terrace development in the NE Mediterranean region (Syria and Turkey): Patterns in relation to crustal type

    Science.gov (United States)

    Bridgland, David R.; Demir, Tuncer; Seyrek, Ali; Daoud, Mohamad; Abou Romieh, Mohammad; Westaway, Rob

    2017-06-01

    It is widely recognized that the optimal development of river terraces globally has been in the temperate latitudes, with NW and Central Europe being areas of particular importance for the preservation of such archives of Quaternary environmental change. There is also a growing consensus that the principal drivers of terrace formation have been climatic fluctuation against a background of progressive (but variable) uplift. Nonetheless river terraces are widely preserved in the Mediterranean region, where they have often been attributed to the effects of neotectonic activity, with a continuing debate about the relative significance of fluctuating temperature (glacials-interglacials) and precipitation (pluvials-interpluvials). Research in Syria and southern-central Turkey (specifically in the valleys of the Tigris and Ceyhan in Turkey, the Kebir in Syria and the trans-border rivers Orontes and Euphrates) has underlined the importance of uplift rates in dictating the preservation pattern of fluvial archives and has revealed different patterns that can be related to crustal type. The NE Mediterranean coastal region has experienced unusually rapid uplift in the Late Quaternary. The relation between the Kebir terraces and the staircase of interglacial raised beaches preserved along the Mediterranean coastline of NW Syria reinforces previous conclusions that the emplacement of the fluvial terrace deposits in the Mediterranean has occurred during colder climatic episodes.

  12. Temporal variation and regional transfer of heavy metals in the Pearl (Zhujiang) River, China.

    Science.gov (United States)

    Zhen, Gengchong; Li, Ying; Tong, Yindong; Yang, Lei; Zhu, Yan; Zhang, Wei

    2016-05-01

    Heavy metals are highly persistent in water and have a particular significance in ecotoxicology. Heavy metals loading from the Pearl River are likely to cause significant impacts on the environment in the South China Sea and the West Pacific. In this study, using monthly monitoring data from a water quality monitoring campaign during 2006-2012, the temporal variation and spatial transfer of six heavy metals (lead (Pb), copper (Cu), cadmium (Cd), zinc (Zn), arsenic (As), and mercury (Hg)) in the Pearl River were analyzed, and the heavy metal fluxes into the sea were calculated. During this period, the annual heavy metal loads discharged from the Pearl River into the South China Sea were 5.8 (Hg), 471.7 (Pb), 1524.6 (Cu), 3819.6 (Zn), 43.9 (Cd), and 621.9 (As) tons, respectively. The metal fluxes showed a seasonal variation with the maximum fluxes occurring from June to July. There is a close association between metal fluxes and runoff. The analysis of the heavy metal transfer from the upstream to the downstream revealed that the transfer from the upstream accounted for a major portion of the heavy metals in the Pearl River Delta. Therefore, earlier industry relocation efforts in the Pearl River watershed may have limited effect on the water quality improvement in surrounding areas. It is suggested that watershed-based pollution control measures focusing on wastewater discharge in both upstream and downstream areas should be developed and implemented in the future.

  13. Geothermal significance of magnetotelluric sounding in the eastern Snake River Plain-Yellowstone Region

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, W.D.; Boehl, J.E.; Bostick, F.X.; Smith, H.W.

    1977-06-10

    Magnetotelluric soundings along a profile extending from the Raft River geothermal area in southern Idaho in Yellowstone National Park in Wyoming reveal a highly anamalous crustal structure involving a conductive zone at depths that range from 18 km in the central part of the eastern Snake River Plain to 7 km beneath the Raft River thermal area and as little as 5 km in Yellowstone. Resistivities in this conductive zone are less than 10 ohm m and at some sites than 1 ohm m. Structural parameters obtained in processing the magnetotelluric data suggest the possibility of a conductive axis along the center of the eastern Snake River Plain, and these parameters also point to very conductive structures beneath the Yellowstone caldera system. A sounding completed in the Island Park caldera can only be modeled with a crustal structure very different from the Yellowstone caldera system, requiring the absence of this conductive zone to depths greater than 25 km in the Island Park caldera. In addition to the deep conductive zone the thickness of extensive surface basalts in the eastern Snake River Plain was mapped geophysically, and units between the basalts and the deep conductive zone were also well defined and fitted to geologic models.

  14. Pasvik River Watercourse, Barents Region: Pollution Impacts and Ecological Responses. Investigations in 1993

    Energy Technology Data Exchange (ETDEWEB)

    Traaen, T.; Moiseenko, T.; Sandimirov, S. and others

    1994-12-31

    The Pasvik River is one of the largest rivers in the Northern Fennoscandia and constitutes the border between Norway and Russia, with catchment area in Finland, Norway and Russia. Besides being strongly regulated for hydroelectric power production, the river is polluted by the smelter in Nikel and other industrial activities and by domestic sewage from the settlements on both sides of the border. This document discusses the pollution of the river and the ecological responses. The two main areas of concern are heavy metals and eutrophication. Very high content of heavy metals in water, lake sediments, macrophytes and fish was found in Kuetsyarvi. Extensive toxic effects were documented on the fish population in the lake. The toxic effects are less than expected from the concentration of heavy metals, which is due to high calcium content, organic matter and eutrophication. Eutrophication is due to the domestic sewage from settlements within the water catchment. Kuetsyarvi has eutrophic status, the lower parts of the Pasvik River have oligo-mesotrophic status according to phosphorus concentrations, and the composition of the planktonic and benthic communities. Because of increased and stabilized water level from hydroelectric power regulations, increased abundance of macrophytes and zoobenthos in shallow areas also have occurred. 77 refs., 32 figs., 28 tabs.

  15. Performance Analysis of Transposition Models Simulating Solar Radiation on Inclined Surfaces: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yu; Sengupta, Manajit

    2016-06-01

    Transposition models are widely used in the solar energy industry to simulate solar radiation on inclined photovoltaic (PV) panels. These transposition models have been developed using various assumptions about the distribution of the diffuse radiation, and most of the parameterizations in these models have been developed using hourly ground data sets. Numerous studies have compared the performance of transposition models, but this paper aims to understand the quantitative uncertainty in the state-of-the-art transposition models and the sources leading to the uncertainty using high-resolution ground measurements in the plane of array. Our results suggest that the amount of aerosol optical depth can affect the accuracy of isotropic models. The choice of empirical coefficients and the use of decomposition models can both result in uncertainty in the output from the transposition models. It is expected that the results of this study will ultimately lead to improvements of the parameterizations as well as the development of improved physical models.

  16. Reconnaissance survey of site 7 of the proposed Three Rivers Regional Landfill and Technology Center, Savannah River Site, Aiken County, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Cabak, M.A.; Beck, M.L.; Gillam, C.; Sassaman, K.E.

    1996-02-01

    This report documents the archaeological investigation of Site 7 of the proposed Three Rivers Regional Landfill and Technology Center in Aiken County on the United States Department of Energy`s Savannah River Site (SRS) in Aiken and Barnwell Counties, South Carolina. Pedestrian and subsurface survey techniques were used to investigate the 1,403-acre project area. Survey resulted in the discovery of 23 previously unrecorded sites and 11 occurrences; six previously recorded sites were also investigated. These sites consist of six prehistoric sites, nine historic sites, and 14 sites with both prehistoric and historic components. Sites locations and project area boundaries are provided on a facsimile of a USGS 7.5 topographic map. The prehistoric components consist of very small, low-density lithic and ceramic scatters; most contain less than 10 artifacts. Six of the prehistoric components are of unknown cultural affiliation, the remaining prehistoric sites were occupied predominately in the Woodland period. The historic sites are dominated by postbellum/modem home places of tenant and yeoman farmers but four historic sites were locations of antebellum house sites (38AK136, 38AK613, 38AK660, and 38AK674). The historic sites also include an African-American school (38AK677).

  17. Regional water quality patterns in an alluvial aquifer: direct and indirect influences of rivers.

    Science.gov (United States)

    Baillieux, A; Campisi, D; Jammet, N; Bucher, S; Hunkeler, D

    2014-11-15

    The influence of rivers on the groundwater quality in alluvial aquifers can be twofold: direct and indirect. Rivers can have a direct influence via recharge and an indirect one by controlling the distribution of fine-grained, organic-carbon rich flood deposits that induce reducing conditions. These direct and indirect influences were quantified for a large alluvial aquifer on the Swiss Plateau (50km(2)) in interaction with an Alpine river using nitrate as an example. The hydrochemistry and stable isotope composition of water were characterized using a network of 115 piezometers and pumping stations covering the entire aquifer. Aquifer properties, land use and recharge zones were evaluated as well. This information provided detailed insight into the factors that control the spatial variability of groundwater quality. Three main factors were identified: (1) diffuse agricultural pollution sources; (2) dilution processes resulting from river water infiltrations, revealed by the δ(18)OH2O and δ(2)HH2O contents of groundwater; and (3) denitrification processes, controlled by the spatial variability of flood deposits governed by fluvial depositional processes. It was possible to quantify the dependence of the nitrate concentration on these three factors at any sampling point of the aquifer using an end-member mixing model, where the average nitrate concentration in recharge from the agricultural area was evaluated at 52mg/L, and the nitrate concentration of infiltrating river at approximately 6mg/L. The study shows the importance of considering the indirect and direct impacts of rivers on alluvial aquifers and provides a methodological framework to evaluate aquifer scale water quality patterns.

  18. Cross-scale intercomparison of climate change impacts simulated by regional and global hydrological models in eleven large river basins

    Energy Technology Data Exchange (ETDEWEB)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Flörke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Yang, T.; Müller, C.; Leng, G.; Tang, Q.; Portmann, F. T.; Hagemann, S.; Gerten, D.; Wada, Y.; Masaki, Y.; Alemayehu, T.; Satoh, Y.; Samaniego, L.

    2017-01-04

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity of impact models designed for either scale to climate variability and change is comparable. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a much better reproduction of reference conditions. However, the sensitivity of two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases with distinct differences in others, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability, but whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models validated against observed discharge should be used.

  19. CRISPR regulation of intraspecies diversification by limiting IS transposition and intercellular recombination.

    Science.gov (United States)

    Watanabe, Takayasu; Nozawa, Takashi; Aikawa, Chihiro; Amano, Atsuo; Maruyama, Fumito; Nakagawa, Ichiro

    2013-01-01

    Mobile genetic elements (MGEs) and genetic rearrangement are considered as major driving forces of bacterial diversification. Previous comparative genome analysis of Porphyromonas gingivalis, a pathogen related to periodontitis, implied such an important relationship. As a counterpart system to MGEs, clustered regularly interspaced short palindromic repeats (CRISPRs) in bacteria may be useful for genetic typing. We found that CRISPR typing could be a reasonable alternative to conventional methods for characterizing phylogenetic relationships among 60 highly diverse P. gingivalis isolates. Examination of genetic recombination along with multilocus sequence typing suggests the importance of such events between different isolates. MGEs appear to be strategically located at the breakpoint gaps of complicated genome rearrangements. Of these MGEs, insertion sequences (ISs) were found most frequently. CRISPR analysis identified 2,150 spacers that were clustered into 1,187 unique ones. Most of these spacers exhibited no significant nucleotide similarity to known sequences (97.6%: 1,158/1,187). Surprisingly, CRISPR spacers exhibiting high nucleotide similarity to regions of P. gingivalis genomes including ISs were predominant. The proportion of such spacers to all the unique spacers (1.6%: 19/1,187) was the highest among previous studies, suggesting novel functions for these CRISPRs. These results indicate that P. gingivalis is a bacterium with high intraspecies diversity caused by frequent insertion sequence (IS) transposition, whereas both the introduction of foreign DNA, primarily from other P. gingivalis cells, and IS transposition are limited by CRISPR interference. It is suggested that P. gingivalis CRISPRs could be an important source for understanding the role of CRISPRs in the development of bacterial diversity.

  20. Incorporating Groundwater Dynamics and Surface/Subsurface Runoff Mechanisms in Regional Climate Modeling over River Basins in China

    Institute of Scientific and Technical Information of China (English)

    QIN Peihua; XIE Zhenghui; YUAN Xing

    2013-01-01

    To improve the capability of numerical modeling of climate-groundwater interactions,a groundwater component and new surface/subsurface runoff schemes were incorporated into the regional climate model RegCM3,renamed RegCM3_Hydro.20-year simulations from both models were used to investigate the effects of groundwater dynamics and surface/subsurface runoff parameterizations on regional climate over seven river basins in China.A comparison of results shows that RegCM3_Hydro reduced the positive biases of annual and summer (June,July,August) precipitation over six river basins,while it slightly increased the bias over the Huaihe River Basin in eastern China.RegCM3_Hydro also reduced the cold bias of surface air temperature from RegCM3 across years,especially for the Haihe and the Huaihe river basins,with significant bias reductions of 0.80℃ and 0.88℃,respectively.The spatial distribution and seasonal variations of water table depth were also well captured.With the new surface and subsurface runoff schemes,RegCM3_Hydro increased annual surface runoff by 0.11-0.62 mm d-1 over the seven basins.Though previous studies found that incorporating a groundwater component tends to increase soil moisture due to the consideration of upward groundwater recharge,our present work shows that the modified runoff schemes cause less infiltration,which outweigh the recharge from groundwater and result in drier soil,and consequently cause less latent heat and more sensible heat over most of the basins.

  1. Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone:Comparison between the Pearl River Delta and Yangtze River Delta Regions

    Institute of Scientific and Technical Information of China (English)

    WANG Xuemei; CHEN Fei; WU Zhiyong; ZHANG Meigen; Mukul TEWARI; Alex GUENTHER; Christine WIEDINMYER

    2009-01-01

    In this paper,the online weather research and forecasting and chemistry (WRF-Chem) model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concentrations over the Pearl River Delta(PRD) and Yangtze River Delta(YRD) regions.Two scenarios of urban maps are used in the WRF-Chem to represent the early 1990s (pre-urbanization) and the current urban distribution in the PRD and the YRD.Month-long simulation results using the above land-use scenarios for March 2001 show that urbanization increases both the day- and night-time 2-m temperatures by about 0.6℃ and 1.4℃,respectively. Daytime reduction in the wind speed by about 3.0 m s-1 is larger than that for the nighttime (0.5 to 2 m s-1).The daytime increase in the PBL height (>200 m) is also larger than the nighttime (50-100 m).The meteorological conditions modified by urbanization lead to detectable ozone-concentration changes in the PRD and the YRD.Urbanization increases the nighttime surface-ozone concentrations by about 4.7%-8.5% and by about 2.9%-4.2% for the daytime.In addition to modifying individual meteorological variables,urbanization also enhances the convergence zones,especially in the PRD.More importantly,urbanization has different effects on the surface ozone for the PRD and the YRD,presumably due to their urbanization characteristics and geographical locations.Even though the PRD has a smaller increase in the surface temperature than the YRD,it has (a) weaker surface wind speed,(b)smaller increase in PBL heights,and (c) stronger convergence zones.The latter three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD than the YRD.

  2. Gulf of Alaska Shelf and Slope Iron and Nitrate Data, Copper River Region, 2010

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These are data from cruises carried out in April, May and July 2010 from the Copper River (AK) mouth to beyond the shelf break, ~150 km from shore. The focus of the...

  3. Characterization of secondary aerosol and its extinction effects on visibility over the Pearl River Delta Region, China.

    Science.gov (United States)

    Deng, Xuejiao; Wu, Dui; Yu, Jianzhen; Lau, Alexis K H; Li, Fei; Tan, Haobo; Yuan, Zibing; Ng, Wai Man; Deng, Tao; Wu, Cheng; Zhou, Xiuji

    2013-09-01

    Aerosol samples collected from July 2007 to March 2008 were used to obtain major aerosol constituents in an urban location in the Pearl River Delta Region (PRD), China. The minimum organic carbon (OC)/elemental carbon (EC) ratio was used to calculate the primary and secondary organic carbon and the extinction effect of the secondary aerosol on visibility was estimated. As indicated in the analysis, the mass of secondary aerosol takes up 50% of the total mass of PM2.5; the OC/EC ratio is larger than 2 and there are significant characteristics of secondary aerosol generation; the levels of secondary OC are comparable with those of sulfate; and there is obvious enrichment of secondary aerosol on more polluted days. In a dry environment, the extinction weight is 59% for the secondary aerosol, while it is as high as 82% if the environment is highly humid (relative humidity [RH] = 95%). The hygroscopic growth of the aerosol can reduce visibility greatly; the secondary aerosol shares much larger quotas on more polluted days. For the Pearl River Delta (PRD), secondary aerosol and carbonaceous aerosol, especially secondary organic carbon (SOC), are a very acute problem; the study of the generating mechanism and sources for secondary aerosol is the key to the effort of controlling visibility in this region. The equation set forth in IMPROVE experiments can only be referenced but is not applicable to evaluate the extinction effect of individual aerosol components on visibility in the PRD region.

  4. Modeling of Regionalized Emissions (MoRE into Water Bodies: An Open-Source River Basin Management System

    Directory of Open Access Journals (Sweden)

    Stephan Fuchs

    2017-03-01

    Full Text Available An accurate budget of substance emissions is fundamental for protecting freshwater resources. In this context, the European Union asks all member states to report an emission inventory of substances for river basins. The river basin management system MoRE (Modeling of Regionalized Emissions was developed as a flexible open-source instrument which is able to model pathway-specific emissions and river loads on a catchment scale. As the reporting tool for the Federal Republic of Germany, MoRE is used to model annual emissions of nutrients, heavy metals, micropollutants like polycyclic aromatic hydrocarbons (PAH, Bis(2-ethylhexylphthalate (DEHP, and certain pharmaceuticals. Observed loads at gauging stations are used to validate the calculated emissions. In addition to its balancing capabilities, MoRE can consider different variants of input data and quantification approaches, in order to improve the robustness of different modeling approaches and to evaluate the quality of different input data. No programming skills are required to set up and run the model. Due to its flexible modeling base, the effect of reduction measures can be assessed. Within strategic planning processes, this is relevant for the allocation of investments or the implementation of specific measures to reduce the overall pollutant emissions into surface water bodies and therefore to meet the requirements of water policy.

  5. Stock assessment of fish species Labeo rohita, Tor tor and Labeo calbasu in the rivers of Vindhyan region, India.

    Science.gov (United States)

    Dwivedi, Amitabh Chandra; Nautiyal, Prakash

    2012-03-01

    A study was conducted on the economically important fishes Labeo rohita (Hamilton 1822), Tortor (Hamilton 1822) and Labeo calbasu (Hamilton 1822) stocks from the Ken, the Paisuni and the Tons rivers in the Vindhyan region. Asymptotic length was maximum in L. rohita (946, 833 and 962 mm) as compared with T. tor (822, 787 and 946 mm) and minimum in L. calbasu (567, 612 and 692 mm) in the Ken, the Paisuni and the Tons rivers, respectively. The growth coefficient and total mortality was maximum in T. torcompared to L. rohita and minimum in L. calbasu. Fishing mortality was maximum in T. tor (2.9, 4.57 and 3.44) and minimum in L. calbasu (0.51, 1.21 and 1.18) while natural mortality was maximum in L. rohita (0.74, 0.94 and 1.86) and minimum in L. calbasu (0.47, 0.65 and 0.68). Natural mortality indicated that the habitat was more suitable for L. calbasu. Comparatively, fishing pressure was very high in T. tor than L. rohita and L. calbasu. Exploitation rate was maximum in T. tor (0.71, 0.82 and 0.84) compared to L. rohita (0.77, 0.74 and 0.56) and minimum in L. calbasu (0.52, 0.65 and 0.63) in the Ken, Paisuni and Tons rivers, respectively.

  6. Determination of estrogenic activity in the river Chienti (Marche Region, Italy) by using in vivo and in vitro bioassays.

    Science.gov (United States)

    Cocci, Paolo; Palermo, Francesco Alessandro; Quassinti, Luana; Bramucci, Massimo; Miano, Antonino; Mosconi, Gilberto

    2016-05-01

    Environmental estrogen-like compounds (i.e. xenoestrogens) are a variety of pollutants, ranging from synthetic to natural occurring molecules, that are found in surface and waste waters over a wide range of concentrations. In aquatic environment, the overall estrogenic activity is often due to the presence of a mixture of chemicals and their degraded products which can induce synergistic effects. Current strategies for monitoring estrogen-like chemicals are based on the use of a battery of in vivo and in vitro ecotoxicological tests. In this regard, the aim of the present work was to carry out a bio-monitoring study for testing estrogenicity of the Chienti river (Marche Region, Italy) by using both an E-screen and a vitellogenin (Vtg) induction assay in juvenile goldfish. Three sites were used for analysis, localized at the mouth (sampling point 1), in the middle (sampling point 2) and at the origin (sampling point 3) of Chienti river. For most of the water samples (i.e. samples collected at sampling points 2 and 3), clear estrogenic activity was detected in the E-screen assay suggesting different proliferation activities in function of the collecting site. In contrast, the Vtg ELISA demonstrated that water samples collected from each sampling point were estrogenic. Overall, we showed for the first time that the estrogenic activities in water samples from the Chienti river were significant in both in vivo and in vitro; we also observed a different sensitivity between bioassays.

  7. Effect of ecological restoration and climate change on ecosystems: a case study in the Three-Rivers Headwater Region, China.

    Science.gov (United States)

    Jiang, Chong; Zhang, Linbo

    2016-06-01

    The Three-Rivers Headwater Region (TRHR) is the headwater of the Yangtze River Basin (YARB), Yellow River Basin (YRB), and Lancang River Basin (LRB); it is known as China's 'Water Tower' owing to its important supply of freshwater. In order to assess ecosystem changes in the TRHR during 2000-2012, we systematically and comprehensively evaluated a combination of model simulation results and actual observational data. The results showed the following: (1) Ecosystem pattern was relatively stable during 2000-2010, with a slight decrease in farmland and desert areas, and a slight increase in grassland and wetland/water-body areas. (2) A warmer and wetter climate, and ecological engineering, caused the vegetation cover and productivity to significantly improve. (3) Precipitation was the main controlling factor for streamflow. A significant increase in precipitation during 2000-2012 resulted in an obvious increase in annual and seasonal streamflow. Glacier melting also contributed to the streamflow increase. (4) The total amount of soil conservation increased slightly from 2000 to 2012. The increase in precipitation caused rainfall erosivity to increase, which enhanced the intensity of soil erosion. The decrease in wind speed decreased wind erosion and the frequency of sandstorms. (5) The overall habitat quality in the TRHR was stable between 2000 and 2010, and the spatial pattern exhibited obvious heterogeneity. In some counties that included nature reserves, habitat quality was slightly higher in 2010 than in 2000, which reflected the effectiveness of the ecological restoration. Overall, the aforementioned ecosystem changes are the combined results of ecological restoration and climate change, and they are likely a local and temporary improvement, rather than a comprehensive and fundamental change. Therefore, more investments and efforts are needed to preserve natural ecosystems.

  8. Reconstructing the Historical Series of Plant Functional Types in the Three-River Headwaters Region in China

    Science.gov (United States)

    Mao, X.; Li, T.

    2016-12-01

    This study uses a physiological biome model to reconstruct the 5910 years historical plant functional type series based on the mechanisms about how environmental constraints affect plant growths. The study area is the Three-Rivers Source Headwaters Region (TRHR) in the south of Qinghai Province of China, which is the source area of the Yangtse River, Yellow River, and Lantsang River, with mean altitude above 4000 meters. The environmental constraints we use are temperature and precipitation. Our results demonstrate that there are only three kinds of biomes existing in this area in the history: the Cool Grass/Shrub, Tundra, and Semidesert. The evolutions of biomes are ruled by two basic patterns. The first is the precipitation driving interconversion of the Semidesert and Tundra and the conversion from the Cool Grass/Shrub to the Semidesert. The second is the temperature driving interconversion of the Tundra and Cool Grass/Shrub. The conversion from the Semidesert to the Cool Grass/Shrub can be generated by the permutations of the first process and the second process. The frequency of the first mode is far higher than the second one, which means that precipitation plays a more active role in the biome evolutions while the temperature makes a long and stable influence on these processes. In the spatial and temporal plant type series generated above, we find that the proportion of the area covered by high quality plants (the Cool Grass/Shrub and Tundra) in around 600 AD is higher than most of other periods in the history, which may led to the rise of the Tibetan Empire. The proportion above, however, decreased sharply in around 1600 AD, which was caused by the Little Ice Age. From this research, we can find the influences of major climatic events on the plant distribution, and understand the interaction or co-evolution of climates and plants more clearly. This study will help us protect our environment more scientifically and with a clearer direction.

  9. Causes of Wetland Degradation and Ecological Restoration in the Yellow River Delta Region

    Institute of Scientific and Technical Information of China (English)

    Zhang Jian-feng; Sun Qi-xiang

    2005-01-01

    Yellow River delta (YRD) is one of the biggest deltas that there is a large area of wetland in the world. Thanks to soil(sands) sediment carried by the Yellow River, there was averagely the newly formed land 21.3 km2in YRD. During the development of petroleum industry and urban expansion, wetlands were degraded due to population growth, irrational land use, in addition to adverse natural eco-environment such as lower precipitation, higher soil evaporation and soil salinazation. The major ecological measures to restore degraded wetland concerned with ensuring water supply, especially establishing perfect irrigation works; protecting virgin plant communities and assisting them to regenerate by the way of site preparation, improving living surroundings; introducing salt-tolerant plants to increase vegetation species and plant coverage, thereby enhancing the capability of wetland to combat contamination and pollution through plant remediation, uptake, absorption, etc. Finally making a comprehensive land use plan,accordingly removing deleterious facilities.

  10. Pollen flow of wheat under natural conditions in the Huanghuai River Wheat Region, China

    OpenAIRE

    Sun, Ai-Qing; Zhang, Chun-Qing; Wu, Cheng-Lai; Gao, Qing-Rong

    2015-01-01

    The transgenic pollen spread is the main pathway of transgenic plant gene flow. The maximum distance of pollen dispersal (horizontal), the spatial dynamics of pollen movement (vertical), and the patterns of pollen dispersal are important considerations in biosafety assessments of genetically modified crops. To evaluate wheat (Triticum aestivum) pollen dispersal, we measured the pollen suspension velocity and analyzed pollen dispersal patterns under natural conditions in the Huanghuai River wh...

  11. Radiocesium fluxes in rivers across the Fukushima fallout region to 2015 and their controlling factors

    Science.gov (United States)

    Onda, Yuichi; Taniguchi, Keisuke; Smith, Hugh; Blake, William; Yoshimura, Kazuya

    2016-04-01

    Due to Fukushima Daiichi Nuclear Power Plant accident, radioactive materials including Cs-134 and Cs-137 were widely distributed in surrounded area. The radiocesiums have been transported in river networks. The monitoring started at 6 sites from June 2011. Subsequently, additional 24 monitoring sites were installed between October 2012 and January 2013. Flow and turbidity were measured at each site in ten minite intervals, and suspended sediments and river water were collected every one or half month to measure Cs-134 and Cs-137 activity concentrations by gamma spectrometry. Fluxes of suspended sediment and radiocesium for the period up to October 2014 are summarised for both the longer-term monitoring stations. Fluxes were computed for monthly intervals. Small gaps in flow data were filled based on linear correlations with monthly data from nearby monitoring stations. Gaps in the suspended sediment load record were filled using L-Q (Load-Discharge) equations derived for each monitoring site based on monthly measurements between November 2012 and March 2015. Monthly L-Q equations were used in place of linear rating curves based on SSC-Q data collected at 10 minute intervals. The total measured flux to the ocean of radiocesium from the Abukuma River at Iwanuma was 14 TBq for the period from August 2011 to October 2014. The transfer of radiocesium with suspended sediment declining until March 2015 and had high correlation with land cover ratio by different land use of the catchments. Also we found positive correlation with radiocesium flux and catchment landuses.

  12. Chemical element transfer of weathering granite regolith in the Three Gorges Dam region of Yangtze River

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Clearing up sediment and regolith on the foundation of the dam in the Three Gorges of the Yangtze River in 1999, riverbed were exposed. On the basis of weathering granite regolith sampled from different portions of the valley landforms, by analysing total chemical contents with X rays fluorescent slice and calculating proper value of chemical element transferring ratio and intensity, the transferring law of chemical elements in different portions of the landforms were concluded: 1) In various landforms of the river valley, the process of desilication is not distinct; 2) in weathering granite regolith of riverbed, easy soluble CaO and MgO are relatively enriched whereas A1203 tends to decrease. The enriching rate of Fe203 is the greatest in various landforms of the river valley; 3) in weathering granite regolith of flood-plain, K20 and MgO contents are relatively enriched; 4) the weathering granite regolith of valley slope is a typical north subtropical weathering regolith, and its chemical weathering degree is in the transition phase from early to middle period; and 5) there is an opposite layer where K20 is relatively leaching and Na20 relatively enriching in 6.5 m depth of all weathering granite regolith.

  13. Multiple climatic cycles imprinted on regional uplift-controlled fluvial terraces in the lower Yalong River and Anning River, SE Tibetan Plateau

    Science.gov (United States)

    He, Zexin; Zhang, Xujiao; Bao, Shuyan; Qiao, Yansong; Sheng, Yuying; Liu, Xiaotong; He, Xiangli; Yang, Xingchen; Zhao, Junxiang; Liu, Ru; Lu, Chunyu

    2015-12-01

    The development of fluvial systems on the southeastern margin of the Tibetan Plateau is linked to significant and rapid late Cenozoic uplift. The relatively complete fluvial terrace sequence preserved along the Yalong River valley and that of its tributary, the Anning River, provides an excellent archive for studying the development of terraces in rapidly uplifting mountainous areas. This study reveals that terrace development is predominantly controlled by multiscale climate cycles and long-term uplift, as shown by terrace dating, sedimentary characteristics, and incision rates. At least six alluvial terrace units were identified in 20 transverse sections through the terraces along about a 600 km length of river and were dated using Electron Spin Resonance (ESR) and Optically Stimulated Luminescence (OSL). The climatostratigraphic positions of the terrace deposits and their respective age constraints suggest that fluvial aggradation was concentrated during Marine Isotope Stages (MIS) 32, 22, 18, 4, 2, and the Younger Dryas (YD) and that incision occurred during the succeeding cold-to-warm transitions. The changes in fluvial style marked by terraces 6, 5, and 4 predominantly occurred in synchrony with the 100-ka Milankovitch climate cycles, while terraces 3 and 2 were controlled by the obliquity-driven 41-ka climate cycles. Finally, the aggradation of terrace T1 occurred in response to the YD stadial. During the intervening time between 0.72 and 0.063 Ma, terraces either did not form or were not preserved, which may suggest that uplift rates varied through time and influenced terrace formation/preservation. The progressive valley incision recorded by these fluvial terraces cannot be entirely explained by climate cycling alone. Temporal and spatial variations in incision rates indicate that the continuing long-term incision has been driven by uplift. The temporal distribution of the incision rates reveals two rapidly uplifting stages in the southeastern Tibetan

  14. Bioaccumulation and risk assessment of per- and polyfluoroalkyl substances in wild freshwater fish from rivers in the Pearl River Delta region, South China.

    Science.gov (United States)

    Pan, Chang-Gui; Zhao, Jian-Liang; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Lai, Hua-Jie; Peng, Feng-Jiao; Liu, Shuang-Shuang; Ying, Guang-Guo

    2014-09-01

    Per- and polyfluoroalkyl substances (PFASs) are used in various industries, which results in their ubiquitous occurrence in the environment. This study determined the concentrations of eighteen PFASs in muscle and liver of nine wild freshwater fish species collected from rivers in the Pearl River Delta (PRD) region, South China, and assessed their bioaccumulation and potential health risks to local people. The results showed that eight and twelve PFASs were detected in the fish muscle and liver samples, respectively. Perfluorooctane sulfonate (PFOS) was found to be the predominant PFAS both in muscle and liver with its highest concentrations of 79ng/g wet weight (ww) in muscle and 1500ng/g ww in liver, followed by Perfluoroundecanoic acid (PFUnDA) and Perfluorotridecanoic acid (PFTrDA) with trace concentrations. The mean PFOS concentrations in fish muscle and liver tissues of the nine collected species ranged from 0.40ng/g in mud carp to 25ng/g in snakehead, and from 5.6ng/g in mud carp to 1100ng/g in snakehead, respectively. Significant positive correlations were found among PFASs both in water and fish, indicating a similar pollution source for these PFASs. In tilapia samples, PFOS concentrations showed an increasing trend with increasing length and weight, but no significant difference between genders. Bioaccumulation factors (logBAF) in fish for the PFASs were in the range from 2.1 to 5.0. The calculated hazard ratios (HR) of PFOS for all fishes were in the range of 0.05-2.8, with four out of nine species (tilapia, chub, leather catfish and snakehead) having their HR values more than 1.0. The results suggest that frequent consumption of these four fish species may pose health risks to local population.

  15. Polymorphisms of the nucleolus organizing regions in Loricaria cataphracta (Siluriformes, Loricariidae) of the upper Paraguay River basin indicate an association with transposable elements.

    Science.gov (United States)

    Porto, F E; Gindri, B S; Vieira, M M R; Borin, L A; Portela-Castro, A L B; Martins-Santos, I C

    2014-03-12

    A cytogenetic analysis of Loricaria cataphracta revealed a diploid number of 2n = 64 chromosomes, distributed as 12 metacentric + 8 submetacentric + 2 subtelocentric + 42 acrocentric, with a fundamental number of 86. Analysis of the nucleolus organizing region (NOR) using silver nitrate impregnation and fluorescence in situ hybridization (18S rDNA probe) techniques showed intra-population chromosomal polymorphism that could be classified into five different patterns (I to V), involving four pairs of chromosomes (8, 9, 12, and 13). In pattern I, the NOR was located in pair 12, whereas in pattern II, the NOR was detected in pair 8; these two patterns were characterized as a simple-NOR system. A multiple NOR system was evident in the other patterns (III, IV, and V). In pattern III, the NOR was located in only one of the homologs of pairs 12 and 8, and in patterns IV and V, the NOR was observed in pair 12 and in only one of the homologs of pairs 9 and 13, respectively. In addition, C-band analysis also showed this pattern of variation, and characterized a polymorphism in relation to the constitutive heterochromatin; the composition of this region was GC-rich (positive CMA3) and 4',6-diamidino-2-phenylindole negative. Transposition of NOR sites for mobile elements is suggested to explain this polymorphism.

  16. Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations

    Directory of Open Access Journals (Sweden)

    Yehoshua Shapira

    2016-01-01

    Full Text Available Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

  17. Inactivation of a transgene due to transposition of insertion sequence (IS136) of Agrobacterium tumefaciens

    Indian Academy of Sciences (India)

    Preeti Rawat; Sanjeev Kumar; Deepak Pental; Pradeep Kumar Burma

    2009-06-01

    Agrobacterium strains harbour insertion sequences, which are known to transpose into genomes as well as into Ti plasmids. In this study we report the inactivation of a transgene due to transposition of the A. tumefaciens insertion sequence IS136. The transposition was discovered following transformation of plant tissues, although the fidelity of the binary vector was confirmed following transformation into Agrobacterium. Such transpositions are rare but can occur and it is thus important to check the fidelity of the binary vector at different times of Agrobacterium growth in order to avoid failure in achieving transgene expression.

  18. The transposition of musical knowledge in intellectual education

    Directory of Open Access Journals (Sweden)

    Carla Cuomo

    2014-05-01

    Full Text Available The construction of European citizenship in the era of complexity requires that the transmission of knowledge be directed towards an intellectual formation, that is, the ‘shaping’ of a critical mind, one that is able to problematize, and hence to discern. This can be achieved by educating towards comprehension. In facing this issue, musicologists ask themselves ‘what to teach’ and ‘how to teach’ it, in order to prepare students to the comprehension of music – these questions form the basis of music didactics as the science of ‘transposing’ savoir savant (learned knowledge into savoir enseigné (didactic knowledge. The paper proposes a model appraoch to music comprehension, through the didactic transposition of a piece by Claude Debussy, La cathédrale engloutie. The example is based on a strategy developed by musicological and methodological-didactic research, and focuses on the continuity among listening, music performance, and music history.

  19. Lateral skull base chondroblastoma resected with facial nerve posterior transposition.

    Science.gov (United States)

    Adnot, J; Langlois, O; Tollard, E; Crahes, M; Auquit-Auckbur, I; Marie, J-P

    2017-05-01

    Chondroblastoma is a rare tumor that can involve the temporal bone. Because it is a benign tumor, functional surgery must be proposed. We report a case of a patient with a massive chondroblastoma operated on with preservation of the facial nerve, and description of the surgical technique. A 37-year-old man presented with a 9-month history of a growing left pre-auricular mass and hearing loss. Neuroimaging showed an osteolytic mass invading the temporal bone and temporomandibular joint. Excision was performed via a transpetrosal and transcochlear approach with posterior transposition of the facial nerve. EMG monitoring was effective in preventing facial palsy. Four years later, no sign of recurrence was observed. Chondroblastoma is a locally aggressive tumor, especially when located in the petrous bone and temporomandibular joint. The suggested treatment is a complete excision. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. An epistemological perspective on the didactical transposition of Gaia theory

    Directory of Open Access Journals (Sweden)

    Marina de Lima-Tavares

    2001-09-01

    Full Text Available This paper is part of larger scope project in which the scientificity of the Gaia theory is analysed, intending to contribute towards a critical appraisal or the role that such a theory might have in biology teaching and in approaching the "environment" transversal theme. The Gaia theory proposes that the biosphere acts as na adaptative control system, keeping the earth in homeostasis. Some authors have proposed that this theory should be incorporated in the school curriculum. In Brazil, it already appears in some biology textbooks. The scientificity of this theory is questioned in this paper, given that its didactical transposition should be suported by a previous demonstration of its scientific nature.

  1. Differential environmental impacts on small and medium size rivers from center of São Paulo State, Brazil, and regional management perspectives

    Directory of Open Access Journals (Sweden)

    Paula Caroline dos Reis Oliveira

    2014-12-01

    Full Text Available AIM: This study aimed to evaluate, comparatively, the influence of distinct environmental impacts in the watershed on the rivers Capivara, Lavapés, Araquá and Pardo and the transference of effects downstream. METHODS: The limnological/water quality study was carried out in rainy (March/2007 and dry (September/2007 seasons, considering 17 sampling stations. RESULTS: Variables such as channel width and depth, water velocity and temperature increased towards the river's mouth; water transparency, velocity and dissolved oxygen were higher in the upstream regions. Light penetration was total at most sampling stations and pH was predominantly acid. The sampling stations impacted by pollution sources, Lavapés and Araquá Rivers, exhibited higher values of electric conductivity, suspended solids, total nitrogen, nitrate, nitrite, ammonium, total dissolved phosphorus, BOD, and thermotolerant coliforms. Higher values of electric conductivity, turbidity and suspended solids were observed in the rainy season, whereas higher chlorophyll concentrations occurred in the dry season. The Lavapés River exhibits the worst environmental condition, while Capivara River is under better state of conservation. This study shows that it is urgent the implementation of measures for preservation and restoration of these regional aquatic ecosystems. All studied rivers were influenced by seasonal variation, sewage discharges and by watershed use and occupation. The TSI is a good analysis tool. The studied rivers export organic matter and TN, TP and SS loads to Tietê and Paranapanema rivers. CONCLUSIONS: This study show the importance of river management and that the accelerated degradation of the river systems indicates the little progress of the Brazilian legislation in terms of preservation and good management practices and that the interface between science, law, management and conservation need to be improved.

  2. Development and application of a novel method for regional assessment of groundwater contamination risk in the Songhua River Basin.

    Science.gov (United States)

    Nixdorf, Erik; Sun, Yuanyuan; Lin, Mao; Kolditz, Olaf

    2017-12-15

    The main objective of this study is to quantify the groundwater contamination risk of Songhua River Basin by applying a novel approach of integrating public datasets, web services and numerical modelling techniques. To our knowledge, this study is the first to establish groundwater risk maps for the entire Songhua River Basin, one of the largest and most contamination-endangered river basins in China. Index-based groundwater risk maps were created with GIS tools at a spatial resolution of 30arc sec by combining the results of groundwater vulnerability and hazard assessment. Groundwater vulnerability was evaluated using the DRASTIC index method based on public datasets at the highest available resolution in combination with numerical groundwater modelling. As a novel approach to overcome data scarcity at large scales, a web mapping service based data query was applied to obtain an inventory for potential hazardous sites within the basin. The groundwater risk assessment demonstrated that contamination risk. These areas were mainly located in the vast plain areas with hotspots particularly in the Changchun metropolitan area. Moreover, groundwater levels and pollution point sources were found to play a significantly larger impact in assessing these areas than originally assumed by the index scheme. Moderate contamination risk was assigned to 27% of the aquifers, predominantly associated with less densely populated agricultural areas. However, the majority of aquifer area in the sparsely populated mountain ranges displayed low groundwater contamination risk. Sensitivity analysis demonstrated that this novel method is valid for regional assessments of groundwater contamination risk. Despite limitations in resolution and input data consistency, the obtained groundwater contamination risk maps will be beneficial for regional and local decision-making processes with regard to groundwater protection measures, particularly if other data availability is limited. Copyright

  3. TRANSPOSITION OF GREAT ARTERIES: NEW INSIGHTS INTO THE PATHOGENESIS

    Directory of Open Access Journals (Sweden)

    Marta eUnolt

    2013-06-01

    Full Text Available Transposition of great arteries (TGA is one of the most common and severe congenital heart diseases (CHD. It is also one of the most mysterious CHD because it has no precedent in phylogenetic and ontogenetic development, it does not represent an alternative physiological model of blood circulation and its etiology and morphogenesis are still largely unknown. However, recent epidemiologic, experimental and genetic data suggest new insights into the pathogenesis. TGA is very rarely associated with the most frequent genetic syndromes, such as Turner, Noonan, Williams or Marfan syndromes, and in Down syndrome, it is virtually absent. The only genetic syndrome with a strong relation with TGA is Heterotaxy. Moreover, TGA is rather frequent in cases of isolated dextrocardia with situs solitus, showing link with defect of visceral situs. In lateralization defects TGA is frequently associated with asplenia syndrome. Nowadays, the most reliable method to induce TGA consists in treating pregnant mice with retinoic acid or with retinoic acid inhibitors. Following such treatment not only cases of TGA with d-ventricular loop have been registered, but also some cases of congenitally corrected transposition of great arteries (CCTGA. In another experiment, the embryos of mice treated with retinoic acid in day 6.5 presented Heterotaxy, suggesting a relationship among these morphologically different CHD. In some families, beside TGA cases, there were first-degree relatives with CCTGA. This data suggest that monogenic inheritance with a variable phenotypic expression could explain the familial aggregation of TGA and CCTGA. In some of these families we previously found multiple mutations in laterality genes including Nodal and ZIC3, confirming a pathogenetic relation between TGA and Heterotaxy. These overall data suggest to include TGA in the pathogenetic group of laterality defects instead of conotruncal abnormalities due to ectomesenchymal tissue migration.

  4. Chronology of Miocene-Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

    Science.gov (United States)

    Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.

    2007-01-01

    Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.

  5. Using NASA's Giovanni System to Simulate Time-Series Stations in the Outflow Region of California's Eel River

    Science.gov (United States)

    Acker, James G.; Shen, Suhung; Leptoukh, Gregory G.; Lee, Zhongping

    2012-01-01

    Oceanographic time-series stations provide vital data for the monitoring of oceanic processes, particularly those associated with trends over time and interannual variability. There are likely numerous locations where the establishment of a time-series station would be desirable, but for reasons of funding or logistics, such establishment may not be feasible. An alternative to an operational time-series station is monitoring of sites via remote sensing. In this study, the NASA Giovanni data system is employed to simulate the establishment of two time-series stations near the outflow region of California s Eel River, which carries a high sediment load. Previous time-series analysis of this location (Acker et al. 2009) indicated that remotely-sensed chl a exhibits a statistically significant increasing trend during summer (low flow) months, but no apparent trend during winter (high flow) months. Examination of several newly-available ocean data parameters in Giovanni, including 8-day resolution data, demonstrates the differences in ocean parameter trends at the two locations compared to regionally-averaged time-series. The hypothesis that the increased summer chl a values are related to increasing SST is evaluated, and the signature of the Eel River plume is defined with ocean optical parameters.

  6. Palms and Palm Communities in the Upper Ucayali River Valley - a Little-Known Region in the Amazon Basin

    DEFF Research Database (Denmark)

    Balslev, Henrik; Eiserhardt, Wolf L.; Kristiansen, Thea;

    2010-01-01

    The Amazon region and its palms are inseparable. Palms make up such an important part of the rain forest ecosystem that it is impossible to imagine the Amazon basin without them. Palms are visible in the canopy and often fill up the forest understory. Palms – because of their edible fruits...... – are cornerstone species for the survival of many animals, and palms contribute substantially to forest inventories in which they are often among the ten most important families. Still, the palms and palm communities of some parts of the Amazon basin remain poorly studied and little known. We travelled to a little......-explored corner of the western Amazon basin, the upper Ucayali river valley. There, we encountered 56 different palms, 18 of which had not been registered for the region previously, and 21 of them were found 150–400 km beyond their previously known limits....

  7. Changes in stress within grassland ecosystems in the three counties of the source regions of the Yangtze and Yellow Rivers

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on a database of more than 40 years of second production process and energy flow records for Maduo,Qumalai and Yushu counties,a dynamic model of the stress within grassland ecosys-tems was established using a nonlinear regression method for this source regions of the Yangtze and Yel-low Rivers.The results show that dynamic curves of stress within grassland ecosystems in the three coun-ties were in the shape of an inverted "U" during the period 1965-2007.It also revealed that the variation in actual amount of livestock inventories reflected the general trends of the stress within the grassland eco-systems in the source regions,although there were many other factors for the increase or reduction in grassland ecosystem stress.

  8. Impacts of climate warming on the frozen ground and eco-hydrology in the Yellow River source region, China.

    Science.gov (United States)

    Qin, Yue; Yang, Dawen; Gao, Bing; Wang, Taihua; Chen, Jinsong; Chen, Yun; Wang, Yuhan; Zheng, Guanheng

    2017-12-15

    The Yellow River source region is located in the transition region between permafrost and seasonally frozen ground on the northeastern Qinghai-Tibet Plateau. The region has experienced severe climate change, especially air temperature increases, in past decades. In this study, we employed a geomorphology-based eco-hydrological model (GBEHM) to assess the impacts of climate change on the frozen ground and eco-hydrological processes in the region. Based on a long-term simulation from 1981 to 2015, we found that the areal mean maximum thickness of seasonally frozen ground ranged from 1.1-1.8m and decreased by 1.2cm per year. Additionally, the ratio of the permafrost area to the total area decreased by 1.1% per year. These decreasing trends are faster than the average in China because the study area is on the sensitive margin of the Qinghai-Tibet Plateau. The annual runoff exhibited variations similar to those of the annual precipitation (R(2)=0.85), although the annual evapotranspiration (ET) exhibited an increasing trend (14.3mm/10a) similar to that of the annual mean air temperature (0.66°C/10a). The runoff coefficient (annual runoff divided by annual precipitation) displayed a decreasing trend because of the increasing ET, and the vegetation responses to climate warming and permafrost degradation were manifested as increases in the leaf area index (LAI) and ET at the start of the growing season. Furthermore, the results showed that changes to the frozen ground depth affected vegetation growth. Notably, a rapid decrease in the frozen ground depth (hydrological processes in the headwater area of the Yellow River have changed because of permafrost degradation, and these changes could further influence the water resources availability in the middle and lower reaches of the basin. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Cross - Scale Intercomparison of Climate Change Impacts Simulated by Regional and Global Hydrological Models in Eleven Large River Basins

    Science.gov (United States)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Florke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Wada, Y.

    2017-01-01

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity to climate variability and climate change is comparable for impact models designed for either scale. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a better reproduction of reference conditions. However, the sensitivity of the two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases, but have distinct differences in other cases, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability. Whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models calibrated and validated against observed discharge should be used.

  10. Immune factors and fatty acid composition in human milk from river/lake, coastal and inland regions of China.

    Science.gov (United States)

    Urwin, Heidi J; Zhang, Jian; Gao, Yixiong; Wang, Chunrong; Li, Lixiang; Song, Pengkun; Man, Qingqing; Meng, Liping; Frøyland, Livar; Miles, Elizabeth A; Calder, Philip C; Yaqoob, Parveen

    2013-06-01

    Breast milk fatty acid composition may be affected by the maternal diet during gestation and lactation. The influence of dietary and breastmilk fatty acids on breast milk immune factors is poorly defined. We determined the fatty acid composition and immune factor concentrations of breast milk from women residing in river/lake, coastal and inland regions of China, which differ in their consumption of lean fish and oily fish. Breast milk samples were collected on days 3–5 (colostrum), 14 and 28 post-partum (PP) and analysed for soluble CD14 (sCD14), transforming growth factor (TGF)-b1, TGF-b2, secretory IgA (sIgA) and fatty acids. The fatty acid composition of breast milk differed between the regions and with time PP. The concentrations of all four immune factors in breast milk decreased over time, with sCD14, sIgA and TGF-b1 being highest in the colostrum in the river and lake region. Breast milk DHA and arachidonic acid (AA) were positively associated, and g-linolenic acid and EPA negatively associated, with the concentrations of each of the four immune factors. In conclusion, breast milk fatty acids and immune factors differ between the regions in China characterised by different patterns of fish consumption and change during the course of lactation. A higher breast milk DHA and AA concentration is associated with higher concentrations of immune factors in breast milk, suggesting a role for these fatty acids in promoting gastrointestinal and immune maturation of the infant.

  11. Impact of river stage prediction methods on stream-aquifer exchanges in a hydro(geo)logical model at the regional scale

    Science.gov (United States)

    Saleh, F.; Flipo, N.; de Fouquet, C.

    2012-04-01

    The main objective of this study is to provide a realistic simulation of river stage in regional river networks in order to improve the quantification of stream-aquifer exchanges and better assess the associated aquifer responses that are often impacted by the magnitude and the frequency of the river stage fluctuations. The study focuses on the Oise basin (17 000 km2, part of the 65 000 km2 Seine basin in Northern France) where stream-aquifer exchanges cannot be assessed directly by experimental methods. Nowadays numerical methods are the most appropriate approaches for assessing stream-aquifer exchanges at this scale. A regional distributed process-based hydro(geo)logical model, Eau-Dyssée, is used, which aims at the integrated modeling of the hydrosystem to manage the various elements involved in the quantitative and qualitative aspects of water resources. Eau-Dyssée simulates pseudo 3D flow in aquifer systems solving the diffusivity equation with a finite difference numerical scheme. River flow is simulated with a Muskingum model. In addition to the in-stream discharge, a river stage estimate is needed to calculate the water exchange at the stream-aquifer interface using the Darcy law. Three methods for assessing in-stream river stages are explored to determine the most appropriate representation at regional scale over 25 years (1980-2005). The first method consists in defining rating curves for each cell of a 1D Saint-Venant hydraulic model. The second method consists in interpolating observed rating curves (at gauging stations) onto the river cells of the hydro(geo)logical model. The interpolation technique is based on geostatistics. The last method assesses river stage using Manning equation with a simplified rectangular cross-section (water depth equals the hydraulic radius). Compared to observations, the geostatistical and the Manning methodologies lead to slightly less accurate (but still acceptable) results offering a low computational cost opportunity

  12. Why is the Arkavathy River drying? A multiple hypothesis approach in a data scarce region

    Directory of Open Access Journals (Sweden)

    V. Srinivasan

    2015-01-01

    Full Text Available The developing world faces unique challenges in achieving water security as it is disproportionately exposed to stressors such as climate change while also undergoing demographic growth, agricultural intensification and industrialization. Investigative approaches are needed that can inform sound policy development and planning to address the water security challenge in the context of data scarcity. We investigated the "predictions under change" problem in the Thippagondanahalli (TG Halli catchment of the Arkavathy sub-basin in South India. River inflows into the TG Halli reservoir have declined since the 1970s, and the reservoir is currently operating at only 20% of its built capacity. The mechanisms responsible for the drying of the river are not understood, resulting in uncoordinated and potentially counter-productive management responses. The objective of this study was to investigate potential explanations of the drying trend and thus obtain predictive insight. We used a multiple working hypothesis approach to investigate the decline in inflow into TG Halli reservoir. Five hypotheses were tested using data from field surveys and reliable secondary sources: (1 changes in rainfall amount, timing and storm intensity, (2 rising temperatures, (3 increased groundwater extraction, (4 expansion of eucalyptus plantations, and (5 increased fragmentation of the river channel. Our results indicate that proximate anthropogenic drivers of change such as groundwater pumping, expansion of eucalyptus plantations, and to a lesser extent channel fragmentation, are much more likely to have caused the decline in surface flows in the TG Halli catchment than changing climate. The case study shows that direct human interventions play a significant role in altering the hydrology of watersheds. The multiple working hypotheses approach presents a systematic way to quantify the relative contributions of anthropogenic drivers to hydrologic change. The approach not only

  13. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    Science.gov (United States)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2016-02-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  14. Assessing Long-Term Trend of Particulate Matter Pollution in the Pearl River Delta Region Using Satellite Remote Sensing.

    Science.gov (United States)

    Li, Ying; Lin, Changqing; Lau, Alexis K H; Liao, Chenghao; Zhang, Yongbo; Zeng, Wutao; Li, Chengcai; Fung, Jimmy C H; Tse, Tim K T

    2015-10-06

    Serious particulate matter (PM) pollution problems in many polluted regions of China have been frequently reported in recent years. Long-term exposure to ambient PM pollution is significantly associated with adverse health effects. Characterizing the long-term trends and variation in PM pollution is a basic requirement for evaluating long-term exposure and for guiding future policies to reduce the effects of air pollution on health. However, long-term, ground-based PM measurements are only available at a few fixed stations. In this study, an algorithm is developed and validated to estimate PM concentrations based on the satellite atmospheric optical depth with 1 km spatial resolution. The long-term trends of PM10 concentrations in the entire Pearl River Delta (PRD) region and different cities are quantified and discussed. From 2001 to 2013, the PM10 pollution of the entire PRD region was dominated by a decreasing trend of -0.15 ± 0.23 μg/m(3)·yr. This decreasing PM10 trend was apparent over 75% of the PRD area, with the most significant decreases observed in the center of the region. However, the remaining 25%, mostly located in the outskirts of the region, showed an increasing PM10 trend. This overall decreasing trend indicates the effectiveness of the control measures applied in the past decade for the primary pollutants.

  15. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    Science.gov (United States)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2017-05-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  16. [Measurement and estimation of grassland evapotranspiration in a mountainous region at the upper reach of Heihe River basin, China].

    Science.gov (United States)

    Yang, Yong; Chen, Ren-sheng; Song, Yao-xuan; Liu, Jun-feng; Han, Chun-tan; Liu, Zhang-wen

    2013-04-01

    Evapotranspiration (ET) is an important component of water cycle, but its measurement in high altitude mountainous region is quite difficult, inducing the insufficient understanding on the actual ET in high altitude mountainous region and the effects of ET on this region' s water cycle. In this paper, two small type weighing mini-lysimeters were applied to measure the daily ET in a piece of grassland in a high altitude mountainous region of the Heihe River basin from July 1st, 2009 to June 30th, 2010. Based on the measured data, the methods of FAO-56 Penman-Monteith (F-P-M), Priestley-Taylor (P-T), and Hargreaves-Samani (H-S) were employed to estimate the ET to analyze the applicability of the three methods for the mountainous region, and the pan coefficient at the measurement spots was discussed. During the measurement period, the total annual ET at the measurement spots was 439.9 mm, accounting for 96.5% of the precipitation in the same period, and the ET showed an obvious seasonal distribution, being 389. 3 mm in May-October, accounting for 88. 5% of the annual value. All the three methods could be well applied to estimate the summer ET but not the winter ET, and their applicability followed the sequence of P-T > F-P-M > H-S. At the measurement spots, the daily pan coefficient in summer was 0.7-0. 8, while that in winter was quite variable.

  17. Relative sea level in the South Alligator River Region, North Australia, during the Holocene

    Energy Technology Data Exchange (ETDEWEB)

    Woodroffe, C.D.; Thom, B.G.; Chappell, J.; Wallensky, E.; Grindrod, J.; Head, J.

    Mangrove sediments are indicators of former sea level. Radiocarbon dating of fragments of mangrove wood from the sediments of the South Alligator tidal river, van Diemen Gulf, Northern Territory, indicates that sea level rose rapidly during the Postglacial Marine Transgression until about 6800 years B.P., when it was within 5 m of its present level. This is somewhat later than results from northeast and southeast Australia, which show the sea reached its present level before 6000 B.P. Further, we find no evidence for falling sea level in the last 5000 years, which has been reported from eastern and southwestern sites.

  18. Does nitrogen or silicon limit phytoplankton production in the Mississippi River plume and nearby regions?

    Science.gov (United States)

    Dortch, Quay; Whitledge, Terry E.

    1992-11-01

    The Mississippi River carries very high concentrations of nutrients into the otherwise oligotrophic Gulf of Mexico, resulting in high primary production and hypoxia along the Louisiana continental shelf. The hypothesis that nitrogen availability controls and ultimately limits phytoplankton production on the shelf was tested by measuring an indicator of nitrogen deficiency, the ratio of intracellular free amino acids/particulate protein (AA/Pr), in the area of the Mississippi River plume on a spring and a summer cruise. Neither AA/Pr ratios or nutrients in the water showed nitrogen limitation to be widespread. Ammonium concentrations were generally quite high, so the lack of phytoplankton nitrogen deficiency can be explained by rapid regeneration rates. Nitrogen limitation was most likely in the summer at high salinities. However, ratios of dissolved nutrient concentrations suggested that silicate was as likely, or sometimes more likely, to be a limiting nutrient than nitrogen. Although silicate depletion may not cause a decrease in productivity, it could result in major changes in phytoplankton size and species composition, and ultimately influence trophodynamics, regeneration, the fate of carbon, and severity and extent of hypoxia.

  19. Natural radioactivity and metal contamination of river sediments in the Calabria region, south of Italy

    Science.gov (United States)

    Caridi, F.; Marguccio, S.; D'Agostino, M.; Belvedere, A.; Belmusto, G.

    2016-05-01

    River sediments from eight different sites of the coast of Calabria, south of Italy, were sampled to determine natural radioactivity and metal concentrations, in order to assess any possible radiological hazard, the level of contamination and the possible anthropogenic impact in the area. Gamma and X-ray fluorescence (XRF) spectrometry were employed and results of this study show that the mean activity concentrations of radium (in secular equilibrium with uranium) ranged from 15.1Bq/kg to 26.7Bq/kg, that of thorium from 21.8Bq/kg to 48.3Bq/kg and that of potassium from 541.3Bq/kg to 1452.2Bq/kg. In terms of mean mass concentrations, XRF analysis revealed that uranium was lower than 1.5ppm (minimum detectable value), thorium ranged from 6.1ppm to 10.3ppm while potassium ranged from 2.5% to 4.4%. The degree of sediment contaminations were computed using an enrichment factor (EF) and geoaccumulation index ( I geo for some potential hazardous elements. Results suggested that enrichment factor and geoaccumulation values of Pb and Mn were greatest among the studied metals. The study revealed that on the basis of computed indexes, the eight investigated rivers can be classified as no polluted ones.

  20. Maxillary canine-first premolar transposition in the permanent dentition: treatment considerations and a case report.

    LENUS (Irish Health Repository)

    Synodinos, Philippos N

    2010-12-01

    Transposition is defined as the interchange of position between two adjacent teeth within the same quadrant of the dental arch. Permanent maxillary canine-premolar transposition is the most commonly observed transposition in the human dentition. Its prevalence is relatively low and its aetiology remains unclear, although it has been associated with genetic factors. It may also be related to a combination of localised factors such as malformation of adjacent teeth, tooth agenesis, retention of the deciduous canine and a history of local trauma. Treatment is selected on an individual case basis after thoroughly considering the overall facial and dental characteristics, duration of treatment, cost, patient preference and the orthodontist\\'s experience. This article provides a case report of maxillary canine transposition in the permanent dentition, successfully managed with orthodontic treatment.

  1. Regulation of DNA transposition by CpG methylation and chromatin structure in human cells.

    Science.gov (United States)

    Jursch, Tobias; Miskey, Csaba; Izsvák, Zsuzsanna; Ivics, Zoltán

    2013-05-15

    The activity of transposable elements can be regulated by different means. DNA CpG methylation is known to decrease or inhibit transpositional activity of diverse transposons. However, very surprisingly, it was previously shown that CpG methylation of the Sleeping Beauty (SB) transposon significantly enhanced transposition in mouse embryonic stem cells. In order to investigate the unexpected response of SB transposition to CpG methylation, related transposons from the Tc1/mariner superfamily, that is, Tc1, Himar1, Hsmar1, Frog Prince (FP) and Minos were tested to see how transposition was affected by CpG methylation. A significant increase of >20-fold in transposition of SB, FP and Minos was seen, whereas Tc1, Himar1 and Hsmar1 showed no difference in transposition upon CpG-methylation. The terminal inverted repeats (TIRs) of the SB, FP and Minos elements share a common structure, in which each TIR contains two functionally important binding sites for the transposase (termed the IR/DR structure). The group of IR/DR elements showed increased excision after CpG methylation compared to untreated transposon donor plasmids. We found that de novo CpG methylation is not required for transposition. A mutated FP donor plasmid with depleted CpG sites in both TIRs was as efficient in transposition as the wild-type transposon, indicating that CpG sites inside the TIRs are not responsible for altered binding of factors potentially modulating transposition. By using an in vivo one-hybrid DNA-binding assay in cultured human cells we found that CpG methylation had no appreciable effect on the affinity of SB transposase to its binding sites. However, chromatin immunoprecipitation indicated that CpG-methylated transposon donor plasmids are associated with a condensed chromatin structure characterized by trimethylated histone H3K9. Finally, DNA compaction by protamine was found to enhance SB transposition. We have shown that DNA CpG methylation upregulates transposition of IR

  2. Simple D-transposition of great arteries operated at the age of 11 years

    Science.gov (United States)

    Asfalou, Iliyasse; Touati, Zakia; Amri, Rachida; Cherti, Mohammed

    2012-01-01

    The simple transposition of the great arteries is a lethal congenital heart disease. The life expectancy of unoperated patients is about 9 months. We report the original observation of a girl with unoperated simple transposition of the great arteries, who survived until the age of 11 years. An atrial switch was successfully performed according to the technique of Senning–Mustard. PMID:24174855

  3. A refined 2010-based VOC emission inventory and its improvement on modeling regional ozone in the Pearl River Delta Region, China.

    Science.gov (United States)

    Yin, Shasha; Zheng, Junyu; Lu, Qing; Yuan, Zibing; Huang, Zhijiong; Zhong, Liuju; Lin, Hui

    2015-05-01

    Accurate and gridded VOC emission inventories are important for improving regional air quality model performance. In this study, a four-level VOC emission source categorization system was proposed. A 2010-based gridded Pearl River Delta (PRD) regional VOC emission inventory was developed with more comprehensive source coverage, latest emission factors, and updated activity data. The total anthropogenic VOC emission was estimated to be about 117.4 × 10(4)t, in which on-road mobile source shared the largest contribution, followed by industrial solvent use and industrial processes sources. Among the industrial solvent use source, furniture manufacturing and shoemaking were major VOC emission contributors. The spatial surrogates of VOC emission were updated for major VOC sources such as industrial sectors and gas stations. Subsector-based temporal characteristics were investigated and their temporal variations were characterized. The impacts of updated VOC emission estimates and spatial surrogates were evaluated by modeling O₃ concentration in the PRD region in the July and October of 2010, respectively. The results indicated that both updated emission estimates and spatial allocations can effectively reduce model bias on O₃ simulation. Further efforts should be made on the refinement of source classification, comprehensive collection of activity data, and spatial-temporal surrogates in order to reduce uncertainty in emission inventory and improve model performance.

  4. Extensive libraries of gene truncation variants generated by in vitro transposition.

    Science.gov (United States)

    Morelli, Aleardo; Cabezas, Yari; Mills, Lauren J; Seelig, Burckhard

    2017-01-26

    The detailed analysis of the impact of deletions on proteins or nucleic acids can reveal important functional regions and lead to variants with improved macromolecular properties. We present a method to generate large libraries of mutants with deletions of varying length that are randomly distributed throughout a given gene. This technique facilitates the identification of crucial sequence regions in nucleic acids or proteins. The approach utilizes in vitro transposition to generate 5' and 3' fragment sub-libraries of a given gene, which are then randomly recombined to yield a final library comprising both terminal and internal deletions. The method is easy to implement and can generate libraries in three to four days. We used this approach to produce a library of >9000 random deletion mutants of an artificial RNA ligase enzyme representing 32% of all possible deletions. The quality of the library was assessed by next-generation sequencing and detailed bioinformatics analysis. Finally, we subjected this library to in vitro selection and obtained fully functional variants with deletions of up to 18 amino acids of the parental enzyme that had been 95 amino acids in length.

  5. 黄河上游高寒区水资源变化的气候响应特征%The Impacts of River Water Resources on Regional Climate over the Upper Yellow River High Cold Region

    Institute of Scientific and Technical Information of China (English)

    吕继强; 沈冰; 莫淑红; 邵年华; 秦毅

    2011-01-01

    In this paper,time series of 49 years monthly runoff,temperature,precipitation and part of the permafrost monitoring data recorded at Jimai control hydrometrical station and Maduo and Dari weather stations in the upper Yellow River high cold region were studied.The annual variation,interannual variation,main influencing factors of river water resources,were investigated using peak pattern analytical method,rate change of wetness-dryness analytical method,Mann-Kendall test,wavelet analysis and grey relational analysis,etc.The river water resources regime in 2008-2014 were obtained by Kernel Principle Component Analysis and Least Square-Support Vector Machines prediction model.The results showed that river runoff demonstrates obvious evolutionary characteristics,the year 1961 is the first catastrophe point at which the runoff begins an upward tendency,it begins to reduce after 1982,until 1999 the second catastrophe point which brought a significantly downward tendency.The results of wavelet analysis and the trend prediction analyses show that the hydrological regime in this area will be little more than the 1990s which will last 3-9 years;after 1986,the maximum seasonal frozen depth reduced,which exacerbated the total annual runoff reduction in upper Yellow River.The prediction results indicate that the river water resources in 2011-2014 will reduce by 25.3% the annual average water resources.%利用黄河高寒区吉迈(达日县)水文站、国家气象局达日、玛多观测站1959—2007年,共计49 a水文、气象及部分冻土监测资料,采用峰型度及丰枯率指数、Mann-Kendall时间序列突变点及趋势检验方法、小波分析法、灰色关联分析等统计方法,分析径流年际、年内变化特征,探讨径流长期变化主要影响因素,并建立核主成分支持向量机(KPCA-LSSVM)预测模型,对未来2011—2014年径流情势进行分析。结果表明,由于区域气候、下垫面条件变化及人为因素影响,

  6. Modelling the effects of land-use and land-cover change on water availability in the Jordan River region

    Directory of Open Access Journals (Sweden)

    R. Schaldach

    2009-08-01

    Full Text Available Within the GLOWA Jordan River project, a first-time overview of the current and possible future land and water conditions of a major part of the Eastern Mediterranean region (ca. 100 000 km2 is given. First, we applied the hydrological model TRAIN to simulate current water availability (runoff and groundwater recharge and irrigation water demand on a 1 km×1 km spatial resolution. The results demonstrate the scarcity of water resources in the study region, with extremely low values of water availability in the semi-arid and arid parts. Then, a set of four divergent scenarios on the future of water has been developed using a stakeholder driven approach. Relevant drivers for land-use/land-cover change were fed into the LandSHIFT.R model to produce land-use and land-cover maps for the different scenarios. These maps were used as input to TRAIN in order to generate scenarios of water availability and irrigation water demand for the region. For this study, two intermediate scenarios were selected, with projected developments ranging between optimistic and pessimistic futures (with regard to social and economic conditions in the region. Given that climate conditions remain unchanged, the simulations show both increases and decreases in water availability, depending on the future pattern of natural and agricultural vegetation and the related dominance of hydrological processes.

  7. City-specific vehicle emission control strategies to achieve stringent emission reduction targets in China's Yangtze River Delta region.

    Science.gov (United States)

    Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wu, Xiaomeng; Shu, Jiawei; Hao, Jiming

    2017-01-01

    The Yangtze River Delta (YRD) region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality. Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants (e.g., CO, HC and PM2.5) in the YRD region. Even in Shanghai, where the emission control implemented are more stringent than in Jiangsu and Zhejiang, we observed little to no reduction in NOx emissions from 2000 to 2010. Emission-reduction targets for HC, NOx and PM2.5 are determined using a response surface modeling tool for better air quality. We design city-specific emission control strategies for three vehicle-populated cities in the YRD region: Shanghai and Nanjing and Wuxi in Jiangsu. Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards, the limitation of vehicle population and usage, and the scrappage of older vehicles is applied, Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020. Therefore, additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles.

  8. Regional ozone pollution and key controlling factors of photochemical ozone production in Pearl River Delta during summer time

    Institute of Scientific and Technical Information of China (English)

    CHANG; ChihChung; CHOU; C.K.Charles; Andreas; Wahner

    2010-01-01

    An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer 2006.Using routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was characterized.According to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban conditions.In addition,both sites were located in high O3 regions.In-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional perspectives.Budget analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production rates.The analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban areas.In the suburban areas,sensitivity to nitrogen oxide(NO) concentrations dominated.Key anthropogenic HCs in both areas are alkenes and aromatics.Significant differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.

  9. Variation of Runoff and Precipitation in the Hekou-Longmen Region of the Yellow River Based on Elasticity Analysis

    Directory of Open Access Journals (Sweden)

    Erhui Li

    2014-01-01

    Full Text Available Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010, Huangfuchuan watershed (from 1954 to 2010, and Yanhe watershed (from 1952 to 2010 in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P=0.01 while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000–2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed.

  10. Variation of runoff and precipitation in the Hekou-Longmen region of the Yellow River based on elasticity analysis.

    Science.gov (United States)

    Li, Erhui; Mu, Xingmin; Zhao, Guangju; Gao, Peng; Shao, Hongbo

    2014-01-01

    Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010), Huangfuchuan watershed (from 1954 to 2010), and Yanhe watershed (from 1952 to 2010) in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P = 0.01) while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000-2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed.

  11. Occurrence and transport of 17 perfluoroalkyl acids in 12 coastal rivers in south Bohai coastal region of China with concentrated fluoropolymer facilities.

    Science.gov (United States)

    Wang, Pei; Lu, Yonglong; Wang, Tieyu; Fu, Yaning; Zhu, Zhaoyun; Liu, Shijie; Xie, Shuangwei; Xiao, Yang; Giesy, John P

    2014-07-01

    Perfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water.

  12. SECURITY RISKS, MYTHS IN A TRANSITIONING SUB-NATIONAL REGIONAL ECONOMY (CROSS RIVER STATE AND IMAGINATIVE GEOGRAPHIES OF NIGERIA

    Directory of Open Access Journals (Sweden)

    J. K. UKWAYI

    2015-03-01

    Full Text Available The emergence of an “international community” through accumulation of perceived risks that contrasts with those risks (of considerably lower levels of seriousness compared to those perceived constitutes one of the interesting (or intriguing subjects of risks and disaster studies surrounding the 9/11 era. The constructions of “imaginative geographies”, have frequently been biased in the practices that underlie the mapping of the foreign places tend to put-down the affected regions in their “paintings” for the global community. The latter are subsequently “demonized” in their ratings of competence for participating in world trade, tourism, travel, among other social/cultural, and economic and political activities. The objective of this article is to highlight how the exaggeration of risks (contrasted to actually existing/lived risks, practices that are frequently associated with such adverse “imaginative geographies” poses sub-national regional development dilemma in Nigeria’s Niger Delta. We trace the roots of adverse “imaginative geographies” of Nigeria to the Abacha dictatorship (1993-1997. Then we highlight the mixed characteristics of the Niger Delta conditions during the “return of positive image recapture” by Nigeria’s federal government (re-democratisation of the Fourth Republic, 1999-present, re-branding campaigns; as well as adverse conditions present. Most significantly, we show that despite these adversities, a combination of favorable geographical size, differentiation, sub-national regional security programme formulation and management taking aims at diversification have created “large oases” of peace and security in Cross River State, a part of the Niger Delta that has been completely unscathed by insurgencies of the nearby sub-national region and further away national origin. Apart from identifying sub-national regions qualifying for delisting from “adverse imaginative geographies” due to

  13. Inducible Transposition of a Heat-Activated Retrotransposon in Tissue Culture.

    Science.gov (United States)

    Masuta, Yukari; Nozawa, Kosuke; Takagi, Hiroki; Yaegashi, Hiroki; Tanaka, Keisuke; Ito, Tasuku; Saito, Hideyuki; Kobayashi, Hisato; Matsunaga, Wataru; Masuda, Seiji; Kato, Atsushi; Ito, Hidetaka

    2016-12-23

    A transposition of a heat-activated retrotransposon named ONSEN required compromise of a small RNA-mediated epigenetic regulation that includes RNA-directed DNA methylation (RdDM) machinery after heat treatment. In the current study, we analyzed the transcriptional and transpositional activation of ONSEN to better understand the underlying molecular mechanism involved in the maintenance and/or induction of transposon activation in plant tissue culture. We found the transposition of heat-primed ONSEN during tissue culture independently of RdDM mutation. The heat activation of ONSEN transcripts was not significantly up-regulated in tissue culture compared with that in heat-stressed seedlings, indicating that the transposition of ONSEN was regulated independently of the transcript level. RdDM-related genes were up-regulated by heat stress in both tissue culture and seedlings. The level of DNA methylation of ONSEN did not show any change in tissue culture, and the amount of ONSEN-derived small RNAs was not affected by heat stress. The results indicated that the transposition of ONSEN was regulated by an alternative mechanism in addition to the RdDM-mediated epigenetic regulation in tissue culture. We applied the tissue culture-induced transposition of ONSEN to Japanese radish, an important breeding species of the family Brassicaceae. Several new insertions were detected in a regenerated plant derived from heat-stressed tissues and its self-fertilized progeny, revealing the possibility of molecular breeding without genetic modification.

  14. Lagtime of river systems to changes in pollutant load on the catchment: a regional scale assessment

    Science.gov (United States)

    Żurek, Anna J.; Różański, Kazimierz; Witczak, Stanisław

    2017-04-01

    Transport of conservative contaminants through groundwater systems (e.g. nitrate under oxidized conditions) is significantly delayed when compared to movement of those contaminants through surface water compartments. Characteristic time scales of groundwater movement may easily reach tens or hundreds of years. This results in large lagtimes of contaminant transport in the subsurface. These lagtimes are particularly important when response of river basins to measures aimed at recovery of good groundwater status is considered. Incorporating lagtime principles into water quality regulations may result in more realistic expectations when such policies are designed and implemented. The lagtime of contaminant transport in the subsurface with respect to transport through surface and near-surface (drainage) runoff can be separated into two components: (i) the delay associated with travel time of water (and contaminants) through the unsaturated zone, and (ii) the delay linked to time scales of groundwater flow, from the recharge area down to the discharge zone (river). Thus, the travel time of water through unsaturated and saturated zones can be considered a quantitative measure of the lagtime. Lagtime in the unsaturated zone on the territory of Poland was assessed on the basis of the existing Groundwater Vulnerability Map of Poland (GVMP) (Witczak et al., 2007; 2011). The adopted approach relies on MRT (Mean Residence Time) of water in the strata separating the saturated aquifer from the land surface, as an integrated vulnerability index. In the framework of GVMP, the MRT is calculated as turnover time of the infiltrating water in the vadose zone. The piston-flow type of water movement through the unsaturated zone is considered. The lagtime in the saturated zone (Tsat) can be approximated by travel time of water, flowing along the local hydraulic gradient to the closest river. The lagtime of river systems with respect to changes in pollutant load on the catchment is a sum

  15. Measuring the Sustainability of Water Plans in Inter-Regional Spanish River Basins

    Directory of Open Access Journals (Sweden)

    María M. Borrego-Marín

    2016-08-01

    Full Text Available This paper analyses and compares the sustainability of the water plans in the Spanish River basins according to the objectives of the Water Framework Directive. Even though the concept of sustainability has been traditionally associated with the triple bottom line framework, composed of economic, environmental, and social dimensions, in this paper sustainability has been enlarged by including governance aspects. Two multicriteria decision analysis approaches are proposed to aggregate the sustainability dimensions. Results show that the environmental dimension plays the most important role in the whole sustainability (40% of water basins, followed by both economic and social criteria (25%. By contrast, the dimension of governance is the least important for sustainability (11%. A classification of the Spanish basins according to their sustainability indicates that the water agency with the highest sustainability is Western Cantabrian, followed by Eastern Cantabrian and Tagus. By contrast, Minho-Sil, Jucar, and Douro are the least sustainable.

  16. Discussion on Forestry Sustainable Development in the Yellow River Delta Region

    Institute of Scientific and Technical Information of China (English)

    SUN Qixiang; ZHANG Jianfeng

    2006-01-01

    The Yellow River Delta (YRD) is one of the biggest deltas that have not been developed in the world.During the turn of the centuries, YRD development is listed in the two major projects in the new century by Shandong provincial government.According to the plan, YRD will become an important energy, chemical and agricultural production base in 15-20 years.In view of its location and natural conditions, so far there exist a lot of environmental problems in YRD.Thus the principle of economic development coordinating with environmental protection must be implemented during YRD development.Forestation is one of the vital measures to cope with environment degradation.Therefore, strategies of forestry development and techniques of tree planting in different land use types are discussed in the paper based on site classification with specific problems involved .

  17. Forest recovery and river discharge at the regional scale of Guangdong Province, China

    Science.gov (United States)

    Zhou, Guoyi; Wei, Xiaohua; Luo, Yan; Zhang, Mingfang; Li, Yuelin; Qiao, Yuna; Liu, Haigui; Wang, Chunlin

    2010-09-01

    Information on how large-scale forest changes affect water resources is important in China as country-wide reforestation programs are being implemented and concerns have arisen over possible water reduction. In this study, water budget analysis and statistical methods were used to assess the effects of significant forest recovery on river discharge at Guangdong Province based on 50 years of data. We used realized water yield (RWY) as a balance term between the outflows from and inflows to the province to represent the river discharge produced solely in Guangdong Province. The relationship between forest recovery and RWY was inferred after quantitatively examining other contributing variables including precipitation, potential evapotranspiration, development of impervious areas, human water consumption, and reservoir constructions. We applied time series analysis to test the statistical relationship between forest recovery and RWYs at annual, wet season, and dry season intervals. Both approaches showed that large-scale forest recovery did not cause significant water reduction over the past 50 years. This finding is contrary to the widely held perception of the trade-off relationship between carbon (reforestation) and water. There were no significant trends in precipitation or in RWY annually and in the wet season, but there was a significant increase of RWY in the dry season over the past 50 years. It is estimated that forest recovery may play a positive role in redistributing water from the wet season to the dry season and, consequently, in increasing water yield in the dry season. The implication of those research findings for future reforestation programs and water resource protection is also discussed.

  18. Evaluation of regional-scale hydrological models using multiple criteria for 12 large river basins on all continents

    Science.gov (United States)

    Huang, Shaochun; Krysanova, Valentina; Hattermann, Fred; Vetter, Tobias; Flörke, Martina; Samaniego, Luis; Arheimer, Berit; Yang, Tao; van Griensven, Ann; Su, Buda; Gelfan, Alexander; Breuer, Lutz; Haberlandt, Uwe

    2016-04-01

    A good performance of hydrological impact models under historical climate and land use conditions is a prerequisite for reliable projections under climate change. The evaluation of nine regional-scale hydrological models considering monthly river discharge, long-term average seasonal dynamics and extremes was performed in the framework of the ISI-MIP project for 12 large river basins on all continents. The modelling tools include: ECOMAG, HBV, HYMOD, HYPE, mHM, SWAT, SWIM, VIC and WaterGAP3. These models were evaluated for the following basins: the Rhine and Tagus in Europe, the Niger and Blue Nile in Africa, the Ganges, Lena, Upper Yellow and Upper Yangtze in Asia, the Upper Mississippi, MacKenzie and Upper Amazon in America, and Darling in Australia. The model calibration and validation was done using WATCH climate data for all cases. The model outputs were evaluated using twelve statistical criteria to assess the fidelity of model simulations for monthly discharge, seasonal dynamics, flow duration curves, extreme floods and low flow. The reproduction of monthly discharge and seasonal dynamics was successful in all basins except the Darling, and the high flows and flood characteristics were also captured satisfactory in most cases. However, the criteria for low flow were below the thresholds in many cases. An overview of this collaborative experiment and main results on model evaluation will be presented.

  19. Integrative taxonomy supports new candidate fish species in a poorly studied neotropical region: the Jequitinhonha River Basin.

    Science.gov (United States)

    Pugedo, Marina Lages; de Andrade Neto, Francisco Ricardo; Pessali, Tiago Casarim; Birindelli, José Luís Olivan; Carvalho, Daniel Cardoso

    2016-06-01

    Molecular identification through DNA barcoding has been proposed as a way to standardize a global biodiversity identification system using a partial sequence of the mitochondrial COI gene. We applied an integrative approach using DNA barcoding and traditional morphology-based bioassessment to identify fish from a neotropical region possessing low taxonomic knowledge: the Jequitinhonha River Basin (Southeastern Brazil). The Jequitinhonha River Basin (JRB) has a high rate of endemism and is considered an area of high priority for fish conservation, with estimates indicating the presence of around 110 native and non-indigenous species. DNA barcodes were obtained from 260 individuals belonging to 52 species distributed among 35 genera, 21 families and 6 orders, including threatened and rare species such as Rhamdia jequitinhonha and Steindachneridion amblyurum. The mean Kimura two-parameter genetic distances within species, genera and families were: 0.44, 12.16 and 20.58 %, respectively. Mean intraspecific genetic variation ranged from 0 to 11.43 %, and high values (>2 %) were recovered for five species. Species with a deep intraspecific distance, possibly flagging overlooked taxa, were detected within the genus Pimelodella. Fifteen species, only identified to the genus level, had unique BINs, with a nearest neighbor distance over 2 % and therefore, potential new candidate species supported by DNA barcoding. The integrative taxonomy approach using DNA barcoding and traditional taxonomy may be a remedy to taxonomy impediment, accelerating species identification by flagging potential new candidate species and to adequately conserve the megadiverse neotropical ichthyofauna.

  20. Assessment of climate change impact on hydrological extremes in two source regions of the Nile River Basin

    Directory of Open Access Journals (Sweden)

    M. T. Taye

    2011-01-01

    Full Text Available The potential impact of climate change was investigated on the hydrological extremes of Nyando River and Lake Tana catchments, which are located in two source regions of the Nile River basin. Climate change scenarios were developed for rainfall and potential evapotranspiration (ETo, considering 17 General Circulation Model (GCM simulations to better understand the range of possible future change. They were constructed by transferring the extracted climate change signals to the observed series using a frequency perturbation downscaling approach, which accounts for the changes in rainfall extremes. Projected changes under two future SRES emission scenarios A1B and B1 for the 2050s were considered. Two conceptual hydrological models were calibrated and used for the impact assessment. Their difference in simulating the flows under future climate scenarios was also investigated.

    The results reveal increasing mean runoff and extreme peak flows for Nyando catchment for the 2050s while unclear trend is observed for Lake Tana catchment for mean volumes and high/low flows. The hydrological models for Lake Tana catchment, however, performed better in simulating the hydrological regimes than for Nyando, which obviously also induces a difference in the reliability of the extreme future projections for both catchments. The unclear impact result for Lake Tana catchment implies that the GCM uncertainty is more important for explaining the unclear trend than the hydrological models uncertainty. Nevertheless, to have a better understanding of future impact, hydrological models need to be verified for their credibility of simulating extreme flows.

  1. Virio- and bacterioplankton in the estuary zone of the Ob River and adjacent regions of the Kara Sea shelf

    Science.gov (United States)

    Kopylov, A. I.; Sazhin, A. F.; Zabotkina, E. A.; Romanenko, A. V.; Romanova, N. D.

    2017-01-01

    The distribution of structural and functional characteristics of virioplankton in the north of the Ob River estuary and the adjacent Kara Sea shelf (between latitudes 71°44'44″ N and 73°45'24″ N) was studied with consideration of the spatial variations in the number ( N B) and productivity ( P B) of bacteria and water properties (temperature, salinity, density) by analyzing samples taken in September 2013. The number of plankton viruses ( N V), the occurrence of visible infected bacteria cells, virus-induced mortality of bacteria, and virioplankton production in the studied region varied within (214-2917) × 103 particles/mL, 0.3-5.6% of NB, 2.2-64.4% of P B, and (6-17248) × 103 particles/(mL day), respectively. These parameters were the highest in water layers with a temperature of +7.3-7.5°C, salinity of 3.75-5.41 psu, and conventional density (στ) of 2.846-4.144. The number of bacterioplankton was (614-822) × 103 cells/mL, and the N V/ N B ratio was 1.1-4.5. A large amount of virus particles were attached to bacterial cells and suspended matter. The data testify to the considerable role of viruses in controlling the number and production of heterotrophic bacterioplankton in the interaction zone of river and sea waters.

  2. Simulation of the Regional Ground-Water-Flow System and Ground-Water/Surface-Water Interaction in the Rock River Basin, Wisconsin

    Science.gov (United States)

    Juckem, Paul F.

    2009-01-01

    A regional, two-dimensional, areal ground-water-flow model was developed to simulate the ground-water-flow system and ground-water/surface-water interaction in the Rock River Basin. The model was developed by the U.S. Geological Survey (USGS), in cooperation with the Rock River Coalition. The objectives of the regional model were to improve understanding of the ground-water-flow system and to develop a tool suitable for evaluating the effects of potential regional water-management programs. The computer code GFLOW was used because of the ease with which the model can simulate ground-water/surface-water interactions, provide a framework for simulating regional ground-water-flow systems, and be refined in a stepwise fashion to incorporate new data and simulate ground-water-flow patterns at multiple scales. The ground-water-flow model described in this report simulates the major hydrogeologic features of the modeled area, including bedrock and surficial aquifers, ground-water/surface-water interactions, and ground-water withdrawals from high-capacity wells. The steady-state model treats the ground-water-flow system as a single layer with hydraulic conductivity and base elevation zones that reflect the distribution of lithologic groups above the Precambrian bedrock and a regionally significant confining unit, the Maquoketa Formation. In the eastern part of the Basin where the shale-rich Maquoketa Formation is present, deep ground-water flow in the sandstone aquifer below the Maquoketa Formation was not simulated directly, but flow into this aquifer was incorporated into the GFLOW model from previous work in southeastern Wisconsin. Recharge was constrained primarily by stream base-flow estimates and was applied uniformly within zones guided by regional infiltration estimates for soils. The model includes average ground-water withdrawals from 1997 to 2006 for municipal wells and from 1997 to 2005 for high-capacity irrigation, industrial, and commercial wells. In addition

  3. Investigating the Impacts of Landuse-landcover (LULC Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    Directory of Open Access Journals (Sweden)

    Hongyan Xi

    2009-11-01

    Full Text Available Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE is of great concern to the local community. Due to great landuse-landcover (LULC changes with rapid industrialization and urbanization in the Pearl River Delta (PRD region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, also possibly threatening to the coastal environment, fishery, and public health in Hong Kong. In addition, recent literature shows that water nutrients in Victoria Harbor of Hong Kong have been proven to be strongly influenced by both the Pearl River and sewage effluent in the wet season (May to September, but it is still unclear how the PRE diluted water intrudes into Victoria Harbor. Due to the cloudy and rainy conditions in the wet season in Hong Kong, ASAR images will be used to monitor the PRE river plumes and track the intruding routes of PRE water nutrients. In this paper, we first review LULC change in the PRD and then show our preliminary results to analyze water quality spatial and temporal information from remote observations with different sensors in the coastal region and estuary. The study will also emphasizes on time series of analysis of LULC trends related to annual sediment yields and critical source areas of erosion for the PRD region since the 1980s.

  4. Accumulation, transfer, and environmental risk of soil mercury in a rapidly industrializing region of the Yangtze River Delta, China

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Biao; Yan, Lianxiang; Sun, Weixia; Zhao, Yongcun; Shi, Xuezheng [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Wang, Mei [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Graduate Univ. of the Chinese Academy of Sciences, Beijing (China); Weindorf, David C. [Louisiana State Univ., Baton Rouge, LA (United States). AgCenter

    2011-06-15

    Purpose: Mercury (Hg) accumulation and transfer in soil ecosystems has been altered on local, regional, and even global scales, and their environmental risk has increasingly been a concern to the public and the scientific community. Materials and methods: A county level region in Zhangjiagang County, the Yangtze River Delta (YRD) region of China and a factory with Hg-contaminated wastewater discharging within the region were selected to study the accumulation, bioavailability, and transfer of Hg from different sources in soils and crops under rapid industrialization, urbanization, and intensive agricultural activities. Regional soil samples close to and away from factories and local soil and crop samples around a typical factory were collected in the YRD region of China. Soil and crop Hg and basic soil properties were examined. Results and discussion: Significant soil Hg accumulation was found in soils away from factories regardless of Cambosols (Entisols) and Anthrosols (Inceptisols), while the mobile HCl-extractable Hg (HCl-Hg) were greater in soils closer to factories due to a decrease and increase in soil pH and organic matter. A high level of soil total Hg (T-Hg) was found around the factory, and soil and crop Hg accumulation in the vicinity of the factory was localized with an exponential decrease as distance away from the wastewater discharge outlet increased. Although Hg accumulated in these soils, the T-Hg levels at only a few sampling sites in acidic Anthrosols area were found to exceed the second most stringent critical value of Chinese Environmental Quality Standards for Soils. Conclusions: Considering the cessation of Hg-containing agrochemicals and limitation of effects of industrial activities on Hg accumulation, more attention should be paid to the changes in soil properties and crop rotations than controlling the pathways of Hg entering soils because the current environmental risk is mobilization of accumulated soil Hg. (orig.)

  5. Alpine grassland soil organic carbon stock and its uncertainty in the three rivers source region of the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Chang

    Full Text Available Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR, alpine grasslands account for more than 75% of the total area. However, the regional carbon (C stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006-2008. We showed that the upper soil (0-30 cm depth in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6-7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution.

  6. [Open window thoracostomy and muscle flap transposition for thoracic empyema].

    Science.gov (United States)

    Nakajima, Y

    2010-07-01

    Open window thoracostomy for thoracic empyema: Open window thoracostomy is a simple, certain and final drainage procedure for thoracic empyema. It is most useful to drain purulent effusion from empyema space, especially for cases with broncho-pleural fistulas, and to clean up purulent necrotic debris on surface of empyema sac. For changing of packing gauzes in empyema space through a window once or twice every day after this procedure, thoracostomy will have to be made on the suitable position to empyema space. Usually skin incision will be layed along the costal bone just at the most expanded position of empyema. Following muscle splitting to thoracic wall, a costal bone just under the incision will be removed as 8-10 cm as long, and opened the empyema space through a costal bed. After the extension of empyema space will be preliminarily examined through a primary window by a finger or a long forceps, it will be decided costal bones must be removed how many (usually 2 or 3 totally) and how long (6-8 cm) to make a window up to 5 cm in diameter. Thickened empyema wall will be cut out just according to a window size, and finally skin edge and empyema wall will be sutured roughly along circular edge. Muscle flap transposition for empyema space: Pediclued muscle flap transposition is one of space-reducing operations for (chronic) empyema Usually this will be co-performed with other several procedures as curettages on empyema surface, closure of bronchopleural fistula and thoracoplasty. This is radically curable for primarily non fistulous empyema or secondarily empyema after open window thoracostomy done for fistula. Furthermore this is less invasive than other radical operations as like pleuro-pneumonectomy, decortication or air-plombage for empyema. There are 2 important points to do this technique. One is a volume of muscle flap and another is good blood flow in flap. The former suitable muscle volume is need to impact empyema space or to close fistula, and the

  7. Considerations and concerting on the european directive transposition to the internal gas market; Mission de reflexion et de concertation sur la transposition de la directive europeenne sur ''le marche interieur du gaz''

    Energy Technology Data Exchange (ETDEWEB)

    Bricq, N

    1999-10-01

    In the framework of the directive 98/30/CE transposition on the the gas internal market, a report has been asked by the First Ministry to define the new form of the gas utilities. The directive deals with the competition opening. The first part presents the gas market organization in France, today and after the transposition. The second part analyses the big stakes of this transposition. (A.L.B)

  8. Development of a new "GFP hop-on assay" system for insertion sequence transposition in Bacillus subtilis 168 using IS4Bsu1 from B. subtilis (natto).

    Science.gov (United States)

    Takahashi, Kiwamu; Chibazakura, Taku; Sekine, Yasuhiko; Yoshikawa, Hirofumi

    2007-04-06

    While most studies involving transposition have focused on analyzing the detailed mechanisms of transposition, the cellular conditions under which transposition occurs remain to be elucidated. In Escherichia coli, papillation assay is a powerful tool for transpositional analysis and the isolation of mutants affecting transposition. On the other hand, while our assay system based on the E. coli papillation assay can detect transpositional events in Bacillus subtilis 168, it is not suitable for quantitating transposition frequency because blue papillae on the transposant colonies of B. subtilis are not countable. We succeeded in developing a new "GFP hop-on assay" system that facilitates quantitative detection of the transposition of the FACS-optimized GFP mutant gene. Our assay system is a step forward in understanding the cellular conditions under which transposition occurs.

  9. Freshwater mussel, Velesunio angasi - a monitor for radium-226 pollution in the Alligator Rivers Region, Northern Territory

    Energy Technology Data Exchange (ETDEWEB)

    Davy, D.R.; Jeffree, R.A. (Australian Atomic Energy Commission Research Establishment, Lucas Heights. Environmental Science Div.)

    1984-10-01

    The state of knowledge of the biology and radioecology of the freshwater mussel, Velesunio angasi, is reviewed. The theoretical response is calculated, in terms of gross parameters suitable for monitoring purposes, for a range of predicted water contaminating events at the Ranger Uranium Mine site in the Alligator Rivers region of the Northern Territory. These results suggest that mussels would be useful biological monitors for events that lead to an increase in the Ra/Ca ratio for the receiving waters. Suitable measurement parameters are Ra:Ca tissue concentration regression and the microstructure of radium distribution within the mussel shell. On the basis of available field data for one event (enhanced erosion of pit borrow material into Georgetown waterhole during the 1980-81 wet season), which had no conventional water quality fingerprint, mussels were shown to be a suitable monitor of such events.

  10. Progress in understanding the formation of fine particulate matter and ground-level ozone in Pearl River Delta region, China

    Science.gov (United States)

    Wang, Xuemei; Wang, Tao; Zheng, Junyu; Shao, Min; Wang, Xinming

    2015-12-01

    In the past three decades, the Pearl River Delta of China has been suffered from severe air pollution due to the rapid increase in energy consumption associated with industrialization and urbanization of the region. The number of hazy days, increased from below 20 days in a year before 1970, to more than 150 days a year during 1980 and 2000. The ground-level ozone levels have also on the rise, with hourly concentration of 160 ppbv being observed in Guangzhou and 201 ppbv in nearby Hong Kong (Zhang et al., 2008). The ozone pollution has been difficult to reduce even in air quality improvement program for the Guangzhou Asian Games (Liu et al., 2013).

  11. Evaluation of water balance components in the Elbe river catchment simulated by the regional climate model CCLM

    Directory of Open Access Journals (Sweden)

    Jan Volkholz

    2014-12-01

    Full Text Available For investigations of feedbacks between the hydrological cycle and the climate system, we assess the performance of the regional climate model CCLM in reconstructing the water balance of the Elbe river catchment. To this end long-term mean precipitation, evapotranspiration and runoff are evaluated. Extremes (90th percentile are also considered in the case of precipitation. The data are provided by a CCLM present-day simulation for Europe that was driven by large-scale global reanalyses. The quality of the model results is analyzed with respect to suitable reference data for the period 1970 to 1999. The principal components of the hydrological cycle and their seasonal variations were captured well. Basin accumulated, averaged daily precipitation, evapotranspiration and runoff differ by no more than 10 % from observations. Larger deviations occur mainly in summer, and at specific areas.

  12. Impact of wet season river flood discharge on phytoplankton absorption properties in the southern Great Barrier Reef region coastal waters

    Science.gov (United States)

    Cherukuru, Nagur; Brando, Vittorio E.; Blondeau-Patissier, David; Ford, Phillip W.; Clementson, Lesley A.; Robson, Barbara J.

    2017-09-01

    Light absorption due to particulate and dissolved material plays an important role in controlling the underwater light environment and the above water reflectance signature. Thorough understanding of absorption properties and their variability is important to estimate light propagation in the water column. However, knowledge of light absorption properties in flood impacted coastal waters is limited. To address this knowledge gap we investigated a bio-optical dataset collected during a flood (2008) in the southern Great Barrier Reef (GBR) region coastal waters. Results presented here show strong impact of river flood discharges on water column stratification, distribution of suspended substances and light absorption properties in the study area. Bio-optical analysis showed phytoplankton absorption efficiency to reduce in response to increased coloured dissolved organic matter presence in flood impacted coastal waters. Biogeophysical property ranges, relationships and parametrisation presented here will help model realistic underwater light environment and optical signature in flood impacted coastal waters.

  13. [Typhus fever morbidity among the military personnel and civilians in the regions around Volga river during World War I].

    Science.gov (United States)

    Raĭkova, S V; Zav'ialov, A I

    2013-07-01

    The article is concerned to the materials about epidemiologic situation of typhus fever in the regions around Volga river (Saratovsky, Samarsky and others) during World War I (1914-1918) among the military personnel of the Russian army and among the civilians. The main reasons for spread of infection, ways of the transmission, and also measures for decreasing of level of morbidity on the different stages of evacuation of patients with typhus fever in the safer hospitals are shown. The most important methods of fighting against epidemic of typhus fever were: isolation of patients in separate special hospitals, desincection and disinfection measures in the foci of infection and organization appropriate sanitary conditions for military man in the army and among civilians. Acquired valuable experience of territorial and military doctors during the period of epidemic of typhus fever allowed receiving complex effective antiepidemic measures of fighting and prevention from this disease.

  14. Environmental changes and human work in the region of the Upper Paraná River floodplain: processes and interactions

    Directory of Open Access Journals (Sweden)

    EA. Tomanik

    Full Text Available The environment and society constitute a complex of elements and interactions. Thus, an understanding of the processes in which the environment and psychosocial elements are involved may not be gained from knowledge of just one isolated variable. Based on such premises, the present paper, which summarizes the results of a series of studies, adopts work relationships as its main focus, but in addition, it has two complementary objectives. One is to present some analyses on the interaction between human actions and the environmental changes that have been taking place in the region of the Upper Paraná River floodplain and in its boundaries. A secondary aim is to show how those two factors have been changing people's working and living conditions and the identity configuration of some of the human groups that live at that site.

  15. Soil hydraulic information for river basin studies in semi-arid regions

    NARCIS (Netherlands)

    Wösten, J.H.M.; Verzandvoort, S.J.E.; Leenaars, J.G.B.; Hoogland, T.; Wesseling, J.G.

    2013-01-01

    Water retention and hydraulic conductivity characteristics of the soil are indispensable for hydrological catchment modelling and for quantifying water limited agricultural production. However, these characteristics are often not available for regions and data scarcity for tropical zones is even

  16. Risk Assessment on Dietary Exposure to Aflatoxin B₁ in Post-Harvest Peanuts in the Yangtze River Ecological Region.

    Science.gov (United States)

    Ding, Xiaoxia; Wu, Linxia; Li, Peiwu; Zhang, Zhaowei; Zhou, Haiyan; Bai, Yizhen; Chen, Xiaomei; Jiang, Jun

    2015-10-15

    Based on the 2983 peanut samples from 122 counties in six provinces of China's Yangtze River ecological region collected between 2009-2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R²) of multiple regression reflected by the aflatoxin B₁ content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B₁ contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B₁ intake from peanuts at the mean peanut consumption level was 0.777-0.790 and 0.343-0.349 ng/(kg·d) for children aged 2-6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year) respectively, generally less than China's current liver cancer incidence of 24.6 cases/(100,000 persons·year). In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B₁ contamination risk assessment in order to protect peanut consumers' safety and boost international trade.

  17. Risk Assessment on Dietary Exposure to Aflatoxin B1 in Post-Harvest Peanuts in the Yangtze River Ecological Region

    Directory of Open Access Journals (Sweden)

    Xiaoxia Ding

    2015-10-01

    Full Text Available Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R2 of multiple regression reflected by the aflatoxin B1 content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B1 contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B1 intake from peanuts at the mean peanut consumption level was 0.777–0.790 and 0.343–0.349 ng/(kg·d for children aged 2–6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year respectively, generally less than China’s current liver cancer incidence of 24.6 cases/(100,000 persons·year. In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B1 contamination risk assessment in order to protect peanut consumers’ safety and boost international trade.

  18. Using an ensemble of regional climate models to assess climate change impacts on water scarcity in European river basins.

    Science.gov (United States)

    Gampe, David; Nikulin, Grigory; Ludwig, Ralf

    2016-12-15

    Climate change will likely increase pressure on the water balances of Mediterranean basins due to decreasing precipitation and rising temperatures. To overcome the issue of data scarcity the hydrological relevant variables total runoff, surface evaporation, precipitation and air temperature are taken from climate model simulations. The ensemble applied in this study consists of 22 simulations, derived from different combinations of four General Circulation Models (GCMs) forcing different Regional Climate Models (RCMs) and two Representative Concentration Pathways (RCPs) at ~12km horizontal resolution provided through the EURO-CORDEX initiative. Four river basins (Adige, Ebro, Evrotas and Sava) are selected and climate change signals for the future period 2035-2065 as compared to the reference period 1981-2010 are investigated. Decreased runoff and evaporation indicate increased water scarcity over the Ebro and the Evrotas, as well as the southern parts of the Adige and the Sava, resulting from a temperature increase of 1-3° and precipitation decrease of up to 30%. Most severe changes are projected for the summer months indicating further pressure on the river basins already at least partly characterized by flow intermittency. The widely used Falkenmark indicator is presented and confirms this tendency and shows the necessity for spatially distributed analysis and high resolution projections. Related uncertainties are addressed by the means of a variance decomposition and model agreement to determine the robustness of the projections. The study highlights the importance of high resolution climate projections and represents a feasible approach to assess climate impacts on water scarcity also in regions that suffer from data scarcity.

  19. Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2007,NOAA/AVHRR NDVI from 1982 to 2006,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to 2006.Two models are developed to evaluate climate change and the climatic suitability of grassland vegetation growth.Average temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2007 at rates of 0.24°C/10 yr,2.32 mm/10 yr,and 2.81 h/10 yr,respectively.The increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.30°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.38 mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2 h/10 yr.The climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and August.Both NDVI observations from 1982 to 2006 and measurements of grass height,dry biomass,and coverage from 1994 to 2006 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source Region.If some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover.

  20. Statistical Seasonal Rainfall Forecast in the Neuquén River Basin (Comahue Region, Argentina

    Directory of Open Access Journals (Sweden)

    Marcela Hebe González

    2015-05-01

    Full Text Available A detailed statistical analysis was performed at the Neuquén river basin using precipitation data for 1980–2007. The hydrological year begins in March with a maximum in June associated with rainfall and another relative maximum in October derived from snow-break. General features of the rainy season and the excess or deficits thereof are analyzed using standardized precipitation index (SPI for a six-month period in the basin. The SPI has a significant cycle of 14.3 years; the most severe excess (SPI greater than 2 has a return period of 25 years, while the most severe droughts (SPI less than −2 have a return period of 10 years. The SPI corresponding to the rainy season (April–September (SPI9 has no significant trend and is used to classify wet/dry years. In order to establish the previous circulation patterns associated with interannual SPI9 variability, the composite fields of wet and dry years are compared. There is a tendency for wet (dry periods to take place during El Niño (La Niña years, when there are positive anomalies of precipitable water over the basin, when the zonal flow over the Pacific Ocean is weakened (intensified and/or when there are negative pressure anomalies in the southern part of the country and Antarctic sea. Some prediction schemes using multiple linear regressions were performed. One of the models derived using the forward stepwise method explained 42% of the SPI9 variance and retained two predictors related to circulation over the Pacific Ocean: one of them shows the relevance of the intensity of zonal flow in mid-latitudes, and the other is because of the influence of low pressure near the Neuquén River basin. The cross-validation used to prove model efficiency showed a correlation of 0.41 between observed and estimated SPI9; there was a probability of detection of wet (dry years of 80% (65% and a false alarm relation of 25% in both cases.

  1. Rapid Global River Flood Risk Assessment under Climate and Socioeconomic Scenarios: An Extreme Case of Eurasian region

    Science.gov (United States)

    Kwak, Young-joo; Magome, Jun; Hasegawa, Akira; Iwami, Yoichi

    2017-04-01

    Causing widespread devastation with massive economic damage and loss of human lives, flood disasters hamper economic growth and accelerate poverty particularly in developing countries. Globally, this trend will likely continue due to increase in flood magnitude and lack of preparedness for extreme events. In line with risk reduction efforts since the early 21st century, the monitors and governors of global river floods should pay attention to international scientific and policy communities for support to facilitate evidence-based policy making with a special interest in long-term changes due to climate change and socio-economic effects. Although advanced hydrological inundation models and risk models have been developed to reveal flood risk, hazard, exposure, and vulnerability at a river basin, it is obviously hard to identify the distribution and locations of continent-level flood risk based on national-level data. Therefore, we propose a methodological possibility for rapid global flood risk assessment with the results from its application to the two periods, i.e., Present (from 1980 to 2004) and Future (from 2075 to 2099). The method is particularly designed to effectively simplify complexities of a hazard area by calculating the differential inundation depth using GFID2M (global flood inundation depth 2-dimension model), despite low data availability. In this research, we addressed the question of which parts in the Eurasian region (8E to 180E, 0N to 60N) can be found as high-risk areas in terms of exposed population and economy in case of a 50-year return period flood. Economic losses were estimated according to the Shared Socioeconomic Pathways (SSP) scenario, and the flood scale was defined using the annual maximum daily river discharge under the extreme conditions of climate change simulated with MRI-AGCM3.2S based on the Representative Concentration Pathways (RCP8.5) emissions scenario. As a preliminary result, the total potential economic loss in the

  2. Impacts of thermal circulations induced by urbanization on ozone formation in the Pearl River Delta region, China

    Science.gov (United States)

    Li, Mengmeng; Song, Yu; Mao, Zhichun; Liu, Mingxu; Huang, Xin

    2016-02-01

    Thermal circulations induced by urbanization could exert important effects on regional ozone (O3) formation through regulating the chemical transformations and transport of O3 and its precursors. In this study, the Weather Research and Forecasting/Chemistry (WRF/Chem) model combined with remote sensing are used to investigate the impacts of urbanization-induced circulations on O3 formation in the Pearl River Delta (PRD) region, China. The urban heat island (UHI) effect in PRD significantly enhances turbulent mixing and modifies local circulations, i.e., initiates the UHI circulation and strengthens the sea breeze, which in turn cause a detectable decrease of daytime O3 concentration (-1.3 ppb) and an increase of O3 (+5.2 ppb) around the nocturnal rush-hours. The suppressed O3 titration destruction due to NOx dilution into the deeper urban boundary layer (200-400 m) is the main reason for elevated nocturnal O3 levels. In the daytime, however, the upward transport of O3 precursors weakens near-surface O3 photochemical production and conversely enhances upper-level O3 generation. Furthermore, the surface UHI convergence flow and intensified sea breeze act to effectively trap O3 at the suburban and coastal regions.

  3. L-Moments Regional Frequency Analysis Methodology Application in maximum rainfall values over the Bogota River's basin

    Science.gov (United States)

    Romero, Claudia; Mesa, Duvan

    2015-04-01

    L-Moments Regional Frequency Analysis Methodology Application in maximum rainfall values over the Bogota River's basin 1°Claudia Patricia Romero Hernández; 2°Duvan Javier Mesa Fernández Universidad Santo Tomas; Colombia The application area of this methodology is the Bogota River's basin, which is located in Cundinamarca; a Colombian department with a total surface area of 589.143 hectares. This basin includes 19 sub-basins, and it is the most densely urbanized of the country. Including its metropolitan area, this region boasts a population of 9.000.000 inhabitants; which composes approximately 23% of Colombia's population and possesses around 19% of the country's industries. This basin has shown a notorious increase of complicated floods frequency in the last few years due to climatic variations. These climatic periods correspond to a weather pattern called Niña Phenomenon (2010-2011), which affected 57.000 citizens in this department and 4,900 people directly in Bogota city, with an estimated economic damage of 277'121,052 USD. The Regional Frequency Analysis methodology is a statistics procedure that consists in adding information from multiple samples in a single large sample, assuming previously that all of these come from the same probability model, except for a difference between them due to a scale factor. These samples are defined by a "regionalization" procedure known as the "Avenue Index" or "Flood Index". This procedure groups several kinds of information that comes from a common probability model, such as temperature, rainfall, and water flow. This model must be similar for all of the weather stations located in a homogeneous region. Maps for each of 4 return periods (5, 10, 50 and 100 years) were developed based on 120 weather stations located on this basin. The information used in this process comes from median monthly rainfall data, based on historical series between 30 and 40 years average. An increase in the annual median rainfall was

  4. Factors Controlling Sediment Load in The Central Anatolia Region of Turkey: Ankara River Basin.

    Science.gov (United States)

    Duru, Umit; Wohl, Ellen; Ahmadi, Mehdi

    2017-01-18

    Better understanding of the factors controlling sediment load at a catchment scale can facilitate estimation of soil erosion and sediment transport rates. The research summarized here enhances understanding of correlations between potential control variables on suspended sediment loads. The Soil and Water Assessment Tool was used to simulate flow and sediment at the Ankara River basin. Multivariable regression analysis and principal component analysis were then performed between sediment load and controlling variables. The physical variables were either directly derived from a Digital Elevation Model or from field maps or computed using established equations. Mean observed sediment rate is 6697 ton/year and mean sediment yield is 21 ton/y/km² from the gage. Soil and Water Assessment Tool satisfactorily simulated observed sediment load with Nash-Sutcliffe efficiency, relative error, and coefficient of determination (R²) values of 0.81, -1.55, and 0.93, respectively in the catchment. Therefore, parameter values from the physically based model were applied to the multivariable regression analysis as well as principal component analysis. The results indicate that stream flow, drainage area, and channel width explain most of the variability in sediment load among the catchments. The implications of the results, efficient siltation management practices in the catchment should be performed to stream flow, drainage area, and channel width.

  5. Factors Controlling Sediment Load in The Central Anatolia Region of Turkey: Ankara River Basin

    Science.gov (United States)

    Duru, Umit; Wohl, Ellen; Ahmadi, Mehdi

    2017-05-01

    Better understanding of the factors controlling sediment load at a catchment scale can facilitate estimation of soil erosion and sediment transport rates. The research summarized here enhances understanding of correlations between potential control variables on suspended sediment loads. The Soil and Water Assessment Tool was used to simulate flow and sediment at the Ankara River basin. Multivariable regression analysis and principal component analysis were then performed between sediment load and controlling variables. The physical variables were either directly derived from a Digital Elevation Model or from field maps or computed using established equations. Mean observed sediment rate is 6697 ton/year and mean sediment yield is 21 ton/y/km² from the gage. Soil and Water Assessment Tool satisfactorily simulated observed sediment load with Nash-Sutcliffe efficiency, relative error, and coefficient of determination ( R²) values of 0.81, -1.55, and 0.93, respectively in the catchment. Therefore, parameter values from the physically based model were applied to the multivariable regression analysis as well as principal component analysis. The results indicate that stream flow, drainage area, and channel width explain most of the variability in sediment load among the catchments. The implications of the results, efficient siltation management practices in the catchment should be performed to stream flow, drainage area, and channel width.

  6. Background concentrations of heavy metals in benthos from transboundary rivers of the Transbaikalia region, Russia.

    Science.gov (United States)

    Kuklin, Aleksei Petrovich; Matafonov, Petr Viktorovich

    2014-02-01

    The concentrations (mg/kg dry weight) of Cu, Zn, As, Cd, Hg, and Pb were measured in benthic macroalgae and invertebrates collected in the upper transboundary tributaries of the Onon River, Transbaikalia, Russia. The background concentration ranges in Cladophora fracta, Ulothrix zonata and Zygnemataceae were: 6.4-9.1 for Cu, 27.2-73.1 for Zn, 0.4-0.9 for Cd, 6.7-35.3 for As, 0.01-0.02 for Hg, and 1.9-4.3 for Pb. In Brachycentrus americanus and Lymnaea media the concentration ranges were: 9.0-25.5 for Cu, 21.4-96.0 for Zn, 0.1-0.3 for Cd, 1.7-5.6 for As, 0.004-0.02 for Hg, and 0.4-2.2 for Pb. The concentrations of Cu, Zn, Pb, and Hg were consistent with data for uncontaminated areas. Under contamination conditions the concentrations in C. fracta were: 938 for Zn, 513 for Pb, and 9.5 for Cd; in Lymnaea media were: 46.8 for Cu, 176 for Zn, 52.3 for Pb, and 3.0 for Cd. All the organisms showed a common response to contamination, and consequently can be used as biomonitors of contamination by heavy metals.

  7. [Obstruction of outflow tracts in complete transposition of great arteries].

    Science.gov (United States)

    Muñoz Castellanos, Luis; Kuri Nivon, Magdalena; Quiñones Cárdenas, Alma Rosa

    2002-01-01

    The obstructive lesions in the outflow tracts of hearts with complete transposition of the great arteries determine the clinical evolution, prognosis, and the selection of surgical procedures. Their knowledge is basic to interpret the imaging findings. From the pathologic specimens collection of the Instituto Nacional de Cardiología "Ignacio Chávez", seventy-tree hearts with this cardiopathy were studied morphologically with the sequential segmental system. Thirty-two hearts had outflow tracts anomalies, being obstructive twenty-eight; among these lesions were: malposition of the infundibular septum, hipertrophyc left infundibulum, prolapse of tricuspid valve tissue through a ventricular septal defect, accessory mitral valve tissue, septal hipertrophy at the left outflow tract level, abnormal insertion of cord tendinae of the mitral valve, anticlockwise malposition of the mitral valve (first report in the literature). The left outflow tract presented obstructive lesions (92.85%) more frequently than the right one. These lesions produce left ventricular hipertrophy, a fundamental feature for the anatomic surgical procedures to be made.

  8. Congenitally corrected transposition in the adult: detection by radionuclide angiocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Guit, G.L.; Kroon, H.M.; Chin, J.G.; Pauwels, E.K.; van Voorthuisen, A.E.

    1985-11-01

    Congenitally corrected transposition (CCT) of the great vessels is an uncommon anomaly usually detected in children because of associated severe cardiac malformations. When these are absent, patients may be hemodynamically normal, but associated cardiac abnormalities are usually present in CCT, leading to symptoms in adulthood. When CCT is suggested in an adult, diagnosis by means of ultrasound may be difficult. Radionuclide angiocardiography (RA) is a simple, noninvasive method by which to diagnose CCT. The authors found consistent morphologic scintigraphic results in 13 patients with proved CCT, leading to establishment of reliable diagnostic criteria. In all instances of situs solitus the aorta ascends and descends on the left with vertical orientation. In the case of situs inversus, the aorta ascends and descends on the right with vertical orientation. The authors criteria are independent of the situs and cardiac position, unlike earlier reports by others. They believe images obtained in the anterior projection are sufficient for the study. The practical application of RA study in patient diagnosis is demonstrated, giving special attention to patients referred because of situs solitus and dextrocardia, in which CCT is known to be present in 50% of cases.

  9. Surgical transposition of the ovaries: Imaging findings in 14 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kier, R.; Chambers, S.K. (Yale Univ. School of Medicine, New Haven, CT (USA))

    1989-11-01

    Pelvic radiation therapy for cervical or vaginal cancer often leads to ovarian failure. To remove the ovaries from the radiation portal and preserve their function, they can be transposed to the lateral abdomen. Serial imaging studies in 14 patients who had undergone ovarian transposition (five bilateral, nine unilateral) were reviewed. Images obtained included 32 CT scans, 20 sonograms, and one MR image. Most transposed ovaries were located along the paracolic gutters near the iliac crests, creating an extrinsic mass effect on adjacent bowel. Detection of surgical clips on the ovary on CT scans allowed confident recognition of all 19 transposed ovaries. Cysts in the transposed ovaries, noted on most imaging studies, did not correlate with complications of pain or hormonal dysfunction. In one case, a large physiologic cyst in a transposed ovary distorted the cecum and was mistaken for a mucocele of the appendix. In another case, a large ovarian cyst was thought to be tumor recurrence or a lymphocele. These findings indicate that although the transposed ovaries can be recognized on CT scans by the surgical clips attached to the ovaries, the appearance of the ovary does not predict reliably the development of complications.

  10. Hydrologic modeling using elevationally adjusted NARR and NARCCAP regional climate-model simulations: Tucannon River, Washington

    Science.gov (United States)

    Praskievicz, Sarah; Bartlein, Patrick

    2014-09-01

    An emerging approach to downscaling the projections from General Circulation Models (GCMs) to scales relevant for basin hydrology is to use output of GCMs to force higher-resolution Regional Climate Models (RCMs). With spatial resolution often in the tens of kilometers, however, even RCM output will likely fail to resolve local topography that may be climatically significant in high-relief basins. Here we develop and apply an approach for downscaling RCM output using local topographic lapse rates (empirically-estimated spatially and seasonally variable changes in climate variables with elevation). We calculate monthly local topographic lapse rates from the 800-m Parameter-elevation Regressions on Independent Slopes Model (PRISM) dataset, which is based on regressions of observed climate against topographic variables. We then use these lapse rates to elevationally correct two sources of regional climate-model output: (1) the North American Regional Reanalysis (NARR), a retrospective dataset produced from a regional forecasting model constrained by observations, and (2) a range of baseline climate scenarios from the North American Regional Climate Change Assessment Program (NARCCAP), which is produced by a series of RCMs driven by GCMs. By running a calibrated and validated hydrologic model, the Soil and Water Assessment Tool (SWAT), using observed station data and elevationally-adjusted NARR and NARCCAP output, we are able to estimate the sensitivity of hydrologic modeling to the source of the input climate data. Topographic correction of regional climate-model data is a promising method for modeling the hydrology of mountainous basins for which no weather station datasets are available or for simulating hydrology under past or future climates.

  11. Climate Change and Its Impact on the Eco-Environment of the Three-Rivers Headwater Region on the Tibetan Plateau, China.

    Science.gov (United States)

    Jiang, Chong; Zhang, Linbo

    2015-09-25

    This study analyzes the impact of climate change on the eco-environment of the Three-Rivers Headwater Region (TRHR), Tibetan Plateau, China. Temperature and precipitation experienced sharp increases in this region during the past 57 years. A dramatic increase in winter temperatures contributed to a rise in average annual temperatures. Moreover, annual runoff in the Lancang (LRB) and Yangtze (YARB) river basins showed an increasing trend, compared to a slight decrease in the Yellow River Basin (YRB). Runoff is predominantly influenced by rainfall, which is controlled by several monsoon systems. The water temperature in the YRB and YARB increased significantly from 1958 to 2007 (p runoff, with a maximum value observed in the 2000s.

  12. The nitrogen cycle in highly urbanized tropical regions and the effect of river-aquifer interactions: The case of Jakarta and the Ciliwung River

    Science.gov (United States)

    Costa, Diogo; Burlando, Paolo; Priadi, Cindy; Shie-Yui, Liong

    2016-09-01

    Groundwater is extensively used in Jakarta to compensate for the limited public water supply network. Recent observations show a rise in nitrate (NO3-) levels in the shallow aquifer, thus pointing at a potential risk for public health. The detected levels are still below national and international regulatory limits for drinking water but a strategy is necessary to contain the growing problem. We combine 3 years of available data in the Ciliwung River, the major river flowing through Jakarta, with a distributed river-aquifer interaction model to characterise the impact of urbanisation on the N-cycle of both surface and groundwater systems. Results show that the N-cycle in the river-aquifer system is heterogeneous in space, seasonal dependent (i.e. flow regime) and strongly affected by urban pollution. Results suggest also that although the main sources of N related groundwater pollution are leaking septic tanks, the aquifer interaction with the Ciliwung River may locally have a strong effect on the concentrations. In the general context of pollution control in urban areas, this study demonstrates how advanced process-based models can be efficiently used in combination with field measurements to bring new insights into complex contamination problems. These are essential for more effective and integrated management of water quality in river-aquifer systems.

  13. Methane Emissions from a Hydrologically Altered Region of the Sprague River Salt Marsh, Phippsburg, ME

    Science.gov (United States)

    Cohen-Kaplan, Dana; Johnson, Beverly; Dostie, Phil; Carey, Joanna

    2016-04-01

    Humans have been altering salt marshes for 200 years, by ditching, or excavating channels to drain pools to reduce mosquito habitat and to make the marsh platform suitable for agriculture. The presence of these ditches has had a negative impact on the marsh hydrology. The Sprague River Salt Marsh, located in Phippsburg, ME, has been ditched for centuries. In 2002, the United States Fish and Wildlife Service installed several ditch-plugs in the marsh in and attempt to restore pool habitat and marsh hydrology. This study seeks to examine the effects of one ditch-plug in particular, and the impact it has had on methane emissions, soil salinity, and soil carbon densities. Three sites above and three sites below the ditch-plug were analyzed in these three areas. Methane emissions were slightly elevated above the ditch-plug relative to below the ditch-plug, with average fluxes of 12.9 +/- 4.83 umol/hr/m2 and 3.5 +/- 0.66 umol/hr/m^2, respectively. Soil salinities were higher above the ditch-plug, and soil carbon densities were higher below the ditch-plug. These results suggest that the hydrologic regime of the study area has been degraded, resulting in methane emissions, interrupted accretion, decreased marsh self-maintenance processes, stagnation and saturation of seawater in the pores of the sediment. Though salt marshes are generally considered effective carbon sinks, methane emissions may play a role on hydrologically altered marshes in terms of their net contribution to greenhouse gas sequestration.

  14. Interaction of prehistoric climate, ecology, and cultures: An example from the Dolores River region of southwest Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, K.L. [Washington State Univ., Richland, WA (United States)

    1995-09-01

    Greenhouse theory suggests global climatic variation will exceed the historical records as the lower atmosphere warms in response to a rise in the concentrations of carbon dioxide, methane, and other gases. The sharp contrast between the large predicted future change and the small climatic changes recorded during the last century indicates that this later period may offer an insufficient basis for appreciating the projected future climate and vegetation changes. Examination of larger-than-historic climatic changes that have occurred in the past (such as those in the Dolores River region) provide a context for evaluating possible future changes and their implications for environmental restoration and land use planning. The zenith of Anasazi Pueblo Indian occupation in the northern Colorado Plateau region coincides with the Little Climatic Optimum (AD 900-1300), and its demise coincides with the Little Ice Age (AD 1250-1300 to AD 1850-1890). Pollen and tree-ring derived indexes of winter and summerprecipitation and growing season length were developed for the La Plata Mountains region of southwestern Colorado. The results show during the height of the Little Climatic Optimum (AD 1000-1100) the region was characterized by a relatively long growing season and by a potential dry farming zone or elevational belt twice as wide as present and supporting Anasazi upland dry farming down to at least 1600 m, an elevation impossible to dry farm today. Between AD 1100 and 1300 the potential dry-farm belt narrowed and finally disappeared with the onset of a period of markedly colder and drier conditions than current. When the Little Ice Age ended in the mid-1800s, another group of farmers (modern Anglos) were able to dry farm. If previous conditions were to return in the near future due to the effects of greenhouse warming, such conditions would be very beneficial to dry farmers.

  15. Estimation of reservoir inflow in data scarce region by using Sacramento rainfall runoff model - A case study for Sittaung River Basin, Myanmar

    Science.gov (United States)

    Myo Lin, Nay; Rutten, Martine

    2017-04-01

    The Sittaung River is one of four major rivers in Myanmar. This river basin is developing fast and facing problems with flood, sedimentation, river bank erosion and salt intrusion. At present, more than 20 numbers of reservoirs have already been constructed for multiple purposes such as irrigation, domestic water supply, hydro-power generation, and flood control. The rainfall runoff models are required for the operational management of this reservoir system. In this study, the river basin is divided into (64) sub-catchments and the Sacramento Soil Moisture Accounting (SAC-SMA) models are developed by using satellite rainfall and Geographic Information System (GIS) data. The SAC-SMA model has sixteen calibration parameters, and also uses a unit hydrograph for surface flow routing. The Sobek software package is used for SAC-SMA modelling and simulation of river system. The models are calibrated and tested by using observed discharge and water level data. The statistical results show that the model is applicable to use for data scarce region. Keywords: Sacramento, Sobek, rainfall runoff, reservoir

  16. Impact of climate Change on Groundwater Recharge in the Tiber River Basin (Central Italy) Using Regional Climate model Outputs

    Science.gov (United States)

    Muluneh, F. B.; Setegn, S. G.; Melesse, A. M.; Fiori, A.

    2011-12-01

    Quantification of the various components of hydrological processes in a watershed remains a challenging topic as the hydrological system is altered by many internal and external drivers. Changes in climate variables can affect the quantity and quality of various components of hydrological cycle. Among others, the local effects of climate change on groundwater resources were not fully studied in different part of the world as compared to the surface water. Moreover, understanding the potential impact of climate change on groundwater is more complex than surface water. The main objective of this study is to analyze the potential impact of climate change on Groundwater recharge in the Tiber River Basin using outputs from Regional Climate model. In this study, a physically-based watershed model called Soil Water Assessment Tool (SWAT) was used to estimate recharge characteristics and its response to climate change in Tiber River Basin (central Italy). The SWAT model was successfully calibrated and validated using observed weather and flow data for the period of 1963-1970 and 1971-1978 respectively. During calibration, the model was highly sensitivity to groundwater flow parameters. Dynamically downscaled rainfall and temperature datasets from ten Regional Climate Models (RCM) archived in 'Prediction of Regional scenarios and Uncertainties for Defining EuropeaN Climate change risks and Effects (PRUDENCE)' were used to force the model to assess the climate change impact on the study area. A quantile-mapping statistical correction procedure was applied to the RCM dataset to correct the inherent systematic biases. The climate change analysis indicated that by the end of 2080s the rainfall was found to decrease nearly up to 40% in dry period and there was an increase in temperature that could reach as high as 3 to 5 oC. By the end of 2080s the ground water recharge shows a decreasing trend as a response to changes in rainfall. However as the timing of both precipitation and

  17. PRELIMINARY DISCUSSIONS OF BASIC CLIMATIC CHARAC- TERISTICS OF PRECIPITATION DURING RAINING SEASONS IN REGIONS SOUTH OF CHANGJIANG RIVER AND ITS RELATIONSHIP WITH SST ANOMALIES

    Institute of Scientific and Technical Information of China (English)

    陈绍东; 王谦谦; 钱永甫

    2003-01-01

    Basic climatic characteristics are analyzed concerning the precipitation anomalies in raining seasons over regions south of the Changjiang River (the Yangtze). It finds that the regions are the earliest in eastern China where raining seasons begin and end. Precipitation there tends to decrease over the past 50 years. Waters bounded by 9(S -1(S, 121(E - 129(E are the key zones of SST anomalies that affect the precipitation in these regions over May ~ July in preceding years. Long-term air-sea interactions make it possible for preceding SST anomalies to affect the general circulation that come afterwards, causing precipitation anomalies in the raining seasons in regions south of the Changjiang River in subsequent years.

  18. Reach-scale variation surface water quality in a reticular canal system in the lower Yangtze River Delta region, China.

    Science.gov (United States)

    Griffiths, James Andrew; Chan, Faith Ka Shun; Zhu, Fangfang; Wang, Vickie; Higgitt, David Laurence

    2017-07-01

    The aim of this research was to assess the spatial and temporal distribution of surface water pollution within a reticular canal system typical of those found in the lower Yangtze River Delta (YRD). For this purpose, surface water quality data was collected from a drainage canal that bisected the southeast district of Ningbo Municipality (Zhejiang) from 2013 to 2015. The sampling transect was designed to represent the change in land-use from the agriculture dominated rural hinterland, to the predominantly urban city-centre. To calculate the representative land-use fraction of each sampling location, the contributing area was defined using an uni-directional 1 km vector line-buffer around the 'upstream' section of canal. The spatial and temporal variation of EC, DO, NH3 and turbidity indicated a measureable difference between the urban and rural sections of the channel. Water quality indicators were most sensitive to urban and parkland land-use types. The study yielded an increased spatial resolution to knowledge of water-quality variability in the urban environment compared to previous studies within the YRD region. The results were used to make recommendations for the development of an effective long-term strategy for the improvement in surface water quality in this region. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Dissolved radon and uranium in groundwater in a potential coal seam gas development region (Richmond River Catchment, Australia).

    Science.gov (United States)

    Atkins, Marnie L; Santos, Isaac R; Perkins, Anita; Maher, Damien T

    2016-04-01

    The extraction of unconventional gas resources such as shale and coal seam gas (CSG) is rapidly expanding globally and often prevents the opportunity for comprehensive baseline groundwater investigations prior to drilling. Unconventional gas extraction often targets geological layers with high naturally occurring radioactive materials (NORM) and extraction practices may possibly mobilise radionuclides into regional and local drinking water resources. Here, we establish baseline groundwater radon and uranium levels in shallow aquifers overlying a potential CSG target formation in the Richmond River Catchment, Australia. A total of 91 groundwater samples from six different geological units showed highly variable radon activities (0.14-20.33 Bq/L) and uranium levels (0.001-2.77 μg/L) which were well below the Australian Drinking Water Guideline values (radon; 100 Bq/L and uranium; 17 μg/L). Therefore, from a radon and uranium perspective, the regional groundwater does not pose health risks to consumers. Uranium could not explain the distribution of radon in groundwater. Relatively high radon activities (7.88 ± 0.83 Bq/L) in the fractured Lismore Basalt aquifer coincided with very low uranium concentrations (0.04 ± 0.02 μg/L). In the Quaternary Sediments aquifers, a positive correlation between U and HCO3(-) (r(2) = 0.49, p groundwater investigations.

  20. [Prediction and simulation of urban area expansion in Pearl River Delta Region under the RCPs climate scenarios].

    Science.gov (United States)

    Jiang, Oun-ou; Deng, Xiang-zheng; Ke, Xin-li; Zhao, Chun-hong; Zhang, Wei

    2014-12-01

    The sizes and number of cities in China are increasing rapidly and complicated changes of urban land use system have occurred as the social economy develops rapidly. This study took the urban agglomeration of Pearl River Delta Region as the study area to explore the driving mechanism of dynamic changes of urban area in the urbanization process under the joint influence of natural environment and social economic conditions. Then the CA (cellular automata) model was used to predict and simulate the urban area changes until 2030 under the designed scenarios of planning and RCPs (representative concentration pathways). The results indicated that urbanization was mainly driven by the non-agricultural population growth and social-economic development, and the transportation had played a fundamental role in the whole process, while the areas with high elevation or steep slope restricted the urbanization. Besides, the urban area would keep an expanding trend regardless of the scenarios, however, the expanding speed would slow down with different inflection points under different scenarios. The urban expansion speed increased in the sequence of the planning scenario, MESSAGE scenario and AIM scenario, and that under the MESSAGE climate scenario was more consistent with the current urban development trend. In addition, the urban expansion would mainly concentrate in regions with the relatively high urbanization level, e.g., Guangzhou, Dongguan, Foshan, Shenzhen, Zhanjiang and Chaoshan.

  1. Assessing the Atmospheric Oxygen Balance in a Region of Rapid Urbanization: A Case Study in the Pearl River Delta, China

    Directory of Open Access Journals (Sweden)

    Jian Peng

    2015-09-01

    Full Text Available Oxygen is a product of photosynthesis and is essential for human survival. It also has a profound effect on ecosystems as the atmospheric oxygen balance is the basis for regional ecological sustainability. The Pearl River Delta (PRD has experienced rapid urbanization and has become one of China’s three major urban agglomerations. This study focused on the oxygen balance of the PRD in 2011, and established a model to calculate the oxygen balance that was suitable for a region of rapid urbanization by applying remote sensing gross primary production data via the C-Fix model. The influencing factors for the oxygen imbalance were analyzed and it was suggested that more attention be paid to the management of oxygen emissions than oxygen consumption. The results indicated that the oxygen balance capacity of the PRD was weak, with an oxygen consumption 9.37 times that of its oxygen emission. Zhaoqing and Huizhou are the main sources of oxygen in the PRD, with an oxygen emission density more than 4.67 times that of Dongguan or Zhuhai. Guangzhou and Shenzhen are the main oxygen sinks, with a total oxygen consumption more than 5.49 times that of Zhaoqing. Moreover, the oxygen balance of the PRD is more sensitive to oxygen emissions than consumption. Therefore, it could be inferred that the land urbanization has a stronger influence on the oxygen balance than the population urbanization.

  2. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Directory of Open Access Journals (Sweden)

    Ling Zhang

    Full Text Available Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014 and near future (2015-2024, by combining two land use models (i.e., Markov chain model and Dyna-CLUE with a hydrological model (i.e., SWAT. The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  3. Examining regional groundwater-surface water dynamics using an integrated hydrologic model of the San Joaquin River basin

    Science.gov (United States)

    Gilbert, James M.; Maxwell, Reed M.

    2017-02-01

    Widespread irrigated agriculture and a growing population depend on the complex hydrology of the San Joaquin River basin in California. The challenge of managing this complex hydrology hinges, in part, on understanding and quantifying how processes interact to support the groundwater and surface water systems. Here, we use the integrated hydrologic platform ParFlow-CLM to simulate hourly 1 km gridded hydrology over 1 year to study un-impacted groundwater-surface water dynamics in the basin. Comparisons of simulated results to observations show the model accurately captures important regional-scale partitioning of water among streamflow, evapotranspiration (ET), snow, and subsurface storage. Analysis of this simulated Central Valley groundwater system reveals the seasonal cycle of recharge and discharge as well as the role of the small but temporally constant portion of groundwater recharge that comes from the mountain block. Considering uncertainty in mountain block hydraulic conductivity, model results suggest this component accounts for 7-23 % of total Central Valley recharge. A simulated surface water budget guides a hydrograph decomposition that quantifies the temporally variable contribution of local runoff, valley rim inflows, storage, and groundwater to streamflow across the Central Valley. Power spectra of hydrograph components suggest interactions with groundwater across the valley act to increase longer-term correlation in San Joaquin River outflows. Finally, model results reveal hysteresis in the relationship between basin streamflow and groundwater contributions to flow. Using hourly model results, we interpret the hysteretic cycle to be a result of daily-scale fluctuations from precipitation and ET superimposed on seasonal and basin-scale recharge and discharge.

  4. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  5. Contribution of land use changes to future flood damage along the river Meuse in the Walloon region

    Directory of Open Access Journals (Sweden)

    A. Beckers

    2013-09-01

    Full Text Available Managing flood risk in Europe is a critical issue because climate change is expected to increase flood hazard in many european countries. Beside climate change, land use evolution is also a key factor influencing future flood risk. The core contribution of this paper is a new methodology to model residential land use evolution. Based on two climate scenarios ("dry" and "wet", the method is applied to study the evolution of flood damage by 2100 along the river Meuse. Nine urbanization scenarios were developed: three of them assume a "current trend" land use evolution, leading to a significant urban sprawl, while six others assume a dense urban development, characterized by a higher density and a higher diversity of urban functions in the urbanized areas. Using damage curves, the damage estimation was performed by combining inundation maps for the present and future 100 yr flood with present and future land use maps and specific prices. According to the dry scenario, the flood discharge is expected not to increase. In this case, land use changes increase flood damages by 1–40%, to €334–462 million in 2100. In the wet scenario, the relative increase in flood damage is 540–630%, corresponding to total damages of €2.1–2.4 billion. In this extreme scenario, the influence of climate on the overall damage is 3–8 times higher than the effect of land use change. However, for seven municipalities along the river Meuse, these two factors have a comparable influence. Consequently, in the "wet" scenario and at the level of the whole Meuse valley in the Walloon region, careful spatial planning would reduce the increase in flood damage by no more than 11–23%; but, at the level of several municipalities, more sustainable spatial planning would reduce future flood damage to a much greater degree.

  6. Evaluation of regional-scale water level simulations using various river routing schemes within a hydrometeorological modelling framework for the preparation of the SWOT mission

    Science.gov (United States)

    Häfliger, V.; Martin, E.; Boone, A. A.; Habets, F.; David, C. H.; Garambois, P. A.; Roux, H.; Ricci, S. M.; Thévenin, A.; Berthon, L.; Biancamaria, S.

    2014-12-01

    The ability of a regional hydrometeorological model to simulate water depth is assessed in order to prepare for the SWOT (Surface Water and Ocean Topography) mission that will observe free surface water elevations for rivers having a width larger than 50/100 m. The Garonne river (56 000 km2, in south-western France) has been selected owing to the availability of operational gauges, and the fact that different modeling platforms, the hydrometeorological model SAFRAN-ISBA-MODCOU and several fine scale hydraulic models, have been extensively evaluated over two reaches of the river. Several routing schemes, ranging from the simple Muskingum method to time-variable parameter kinematic and diffusive waves schemes with time varying parameters, are tested using predetermined hydraulic parameters. The results show that the variable flow velocity scheme is advantageous for discharge computations when compared to the original Muskingum routing method. Additionally, comparisons between water level computations and in situ observations led to root mean square errors of 50-60 cm for the improved Muskingum method and 40-50 cm for the kinematic-diffusive wave method, in the downstream Garonne river. The error is larger than the anticipated SWOT resolution, showing the potential of the mission to improve knowledge of the continental water cycle. Discharge computations are also shown to be comparable to those obtained with high-resolution hydraulic models over two reaches. However, due to the high variability of river parameters (e.g. slope and river width), a robust averaging method is needed to compare the hydraulic model outputs and the regional model. Sensitivity tests are finally performed in order to have a better understanding of the mechanisms which control the key hydrological processes. The results give valuable information about the linearity, Gaussianity and symetry of the model, in order to prepare the assimilation of river heights in the model.

  7. CONFLICT OF AQUATIC RESOURCES AND ITS UNDERLYING CAUSES: A CASE STUDY FROM DONAN RIVER AREA, SEGARA ANAKAN REGION, CILACAP, CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    Taufik Budhi Pramono

    2009-04-01

    Full Text Available This research aimed to know internally conflict on the use of aquatic  resources at around Donan River, Segara Anakan region Cilacap.  Using on fisheries resources was not free against potential conflict among the user or with its interest’s one related to that resources.  The lack on capability of identified conflict would be a limiting factor for the implementation on the fisheries resources management program.  The research was hold in the region of Segara Anakan, Donan River from August until October 2005.  The data collection techniques applied in this survey included questionnaire; observation; in-depth interview with leaders of fisherman organizations; and focus group discussion. Quantitative data was analyzed by descriptive statistics.  The research showed that fisherman’s community along Donan River line were not out of inside potentially conflict among inter micro-micro, intra micro-micro and intra micro-macro.  This potential conflict were appeared because of presence on the different perception belong to its authority access against Donan River and their open system on the fisheries resources management.Keywords : Conflict, Donan River, Aquatic Resources, Fisherman Community

  8. Study on Freshwater Macroinvertebrates of Some Tanzanian Rivers as a Basis for Developing Biomonitoring Index for Assessing Pollution in Tropical African Regions

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    Julius D. Elias

    2014-01-01

    Full Text Available Macroinvertebrates and physicochemical parameters were assessed at 15 sites along five rivers in Kilimanjaro region, Tanzania, with the aim of understanding their ecological status and setting a base to the development of a biological index for tropical regions. Investigated rivers that occur within Pangani basin include Karanga, Rau, Lumbanga, Sere, and Umbwe. Sampling sites were categorized according to the level of water and habitat quality as follows: reference or least impacted (4 sites, moderately impacted (5 sites, and highly impacted (6 sites sites. A total of 12,527 macroinvertebrates belonging to 13 orders and 48 families were recorded. The highest total abundance of 4,110 individuals per m2 was found in Karanga river, while Umbwe river had the lowest with 1,203 individuals per m2. Chironomidae was the most abundant family (2,588 individuals per m2 and the least were Hydridae and Thiaridae, each having 5 individuals per m2. High numbers of taxa were noted among the orders: Ephemeroptera (8, Odonata (8, Diptera (7, and Trichoptera (6. In conclusion, orders with greater diversity of macroinvertebrate families offer a wide range of tolerance to pollution and, thus can potentially be used to develop a biomonitoring index for evaluating pollution in tropical African rivers.

  9. Contribution of the upper river, the estuarine region, and the adjacent sea to the heavy metal pollution in the Yangtze Estuary.

    Science.gov (United States)

    Yin, Su; Wu, Yuehan; Xu, Wei; Li, Yangyang; Shen, Zhenyao; Feng, Chenghong

    2016-07-01

    To determine whether the discharge control of heavy metals in the Yangtze River basin can significantly change the pollution level in the estuary, this study analyzed the sources (upper river, the estuarine region, and the adjacent sea) of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) in dissolved and particulate phases in the surface water of the estuary during wet, normal, and dry seasons. Metal sources inferred from section fluxes agree with those in statistical analysis methods. Heavy metal pollution in the surface water of Yangtze Estuary primarily depends on the sediment suspension and the wastewater discharge from estuary cities. Upper river only constitutes the main source of dissolved heavy metals during the wet season, while the estuarine region and the adjacent sea (especially the former) dominate the dissolved metal pollution in the normal and dry seasons. Particulate metals are mainly derived from sediment suspension in the estuary and the adjacent sea, and the contribution of the upper river can be neglected. Compared with the hydrologic seasons, flood-ebb tides exert a more obvious effect on the water flow directions in the estuary. Sediment suspension, not the upper river, significantly affects the suspended particulate matter concentration in the estuary.

  10. RESEARCH: Effects of Recent Volcanic Eruptions on Aquatic Habitat in the Drift River, Alaska, USA: Implications at Other Cook Inlet Region Volcanoes.

    Science.gov (United States)

    DORAVA; MILNER

    1999-02-01

    / Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano. During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano. KEY WORDS: Aquatic habitat; Volcanoes; Lahars; Lahar-runout flows; Macroinvertebrates; Community structure; Community composition

  11. The Changing Cold Regions Network: Atmospheric, Cryospheric, Ecological and Hydrological Change in the Saskatchewan and Mackenzie River Basins, Canada (Invited)

    Science.gov (United States)

    Wheater, H. S.; DeBeer, C.

    2013-12-01

    The cold interior of Northwestern Canada has one of the world's most extreme and varied climates and, as with other regions across the Arctic, is experiencing rapid environmental change. The Changing Cold Regions Network (CCRN) is a new Canadian research network devoted to addressing key challenges and globally-important issues facing the Arctic by improving the understanding of past and ongoing changes in climate, land, vegetation, and water, and predicting their future integrated responses, with a geographic focus on the Saskatchewan and Mackenzie River Basins. The network is funded for 5 years (2013-18) by the Natural Sciences and Engineering Research Council of Canada, and combines the unique expertise of 36 Canadian scientists representing 8 universities and 4 Federal government agencies, as well as 15 international researchers from the United States, China, Australia, the UK, France, and Germany. The network will also involve the World Climate Research Programme, NASA, the Canadian Space Agency, and the National Center for Atmospheric Research. CCRN will integrate existing and new experimental data with modelling and remote sensing products to understand, diagnose and predict changing land, water and climate, and their interactions and feedbacks, for Northwestern Canada's cold interior. It will use a network of world class observatories to study the detailed connections among changing climate, ecosystems and water in the permafrost regions of the Sub-arctic, the Boreal Forest, the Western Cordillera, and the Prairies. Specifically, the network will: 1. Document and evaluate observed Earth system change, including hydrological, ecological, cryospheric and atmospheric components over a range of scales from local observatories to biome and regional scales; 2. Improve understanding and diagnosis of local-scale change by developing new and integrative knowledge of Earth system processes, incorporating these processes into a suite of process-based integrative

  12. Aerosol size distribution characteristics of organosulfates in the Pearl River Delta region, China

    Science.gov (United States)

    Kuang, Bin Yu; Lin, Peng; Hu, Min; Yu, Jian Zhen

    2016-04-01

    Organosulfates (OSs) have been detected in various atmospheric environments, but their particle size distribution characteristics are unknown. In this work, we examined their size distributions in ambient aerosols to gain insights into the formation processes. Size-segregated aerosol samples in the range of 0.056-18 μm were collected using a ten-stage impactor at a receptor site in Hong Kong in both summer and winter and in Nansha in the Pearl River Delta in winter. The humic-like substances fraction in the size-segregated samples was isolated and analyzed using electrospray ionization coupled with an Orbitrap Ultra High Resolution Mass Spectrometer. Through accurate mass measurements, ∼190 CHOS and ∼90 CHONS formulas were tentatively identified to be OS compounds. Among them, OS compounds derived from isoprene, α-/β-pinene, and limonene and alkyl OSs having low double bond equivalents (DBE = 0,1) and 0-2 extra O beyond those in -OSO3 were found with high intensity. The biogenic volatile organic compounds-derived OS formulas share a common characteristic with sulfate in that the droplet mode dominated, peaking in either 0.56-1.0 or 1.0-1.8 μm size bin, reflecting sulfate as their common precursor. Most of these OSs have a minor coarse mode, accounting for 0-45%. The presence of OSs on the coarse particles is hypothesized to be a result of OSs on small particle (<0.32 μm) coagulating with coarse particles, as the abundance ratios of OS to non-sea-salt sulfate present on the coarse particles were similar to those on particles <0.32 μm. Among a few pairs of CHONS and CHOS that could be linked up through hydrolysis of a nitrooxy group in the CHONS form (e.g., m/z 294: C10H16O7NS- vs. m/z 249 C10H17O5S- from α/β-pinene, differing by (+H2O-HNO3)), the CHONS compounds had an enhanced coarse mode presence. This could be interpreted as a result of slower hydrolysis of the CHONS compounds on the alkali coarse particles. The low DBE alkyl OS compounds have a

  13. Regional patterns of particulate spectral absorption in the Pearl River estuary

    Institute of Scientific and Technical Information of China (English)

    CAO Wenxi; YANG Yuezhong; XU Xiaoqiang; HUANG Liangmin; ZHANG Jianlin

    2003-01-01

    Spectral absorption coefficients of the total particulate, ap(λ), nonalgal particulate, ad(λ), and phytoplankton pigment, aph(λ), in the Pearl River estuary and its vicinity waters were determined using the quantitative filter technique. The particulate absorption ap(443) ranged from 0.04 to 1.82 m-1, withthe corresponding aph(443) ranging from 0.016 to 0.484 m-1. Two typical spectral patterns are found for the total particulate absorption. For the first typicalspectral pattern, the total particulate absorption spectra are similar to that of nonalgal particulate, with values of absorption coefficient decreasing with wavelength. In contrast, for the second spectral pattern the spectral absorptionsby total particulate are very similar to that of phytoplankton pigment. The spectral dependency of absorption by nonalgal particulate follows an exponential increase toward short wavelengths, with an average slope of 0.012±0.002 nm-1. Thenonalgal absorption and the fraction of the nonalgal particulate absorption to the total particulate absorption exhibit a distinct trend of decreasing with salinity of the surface water. Phytoplankton pigment absorption exhibits a clear trend of increasing nonlinearly with chlorophyll a concentration. The relationships between the phytoplankton pigment absorption and chlorophyll a concentration can be described by power law, with the determination coefficient r2 of 0.82. Butonly weak relationships between ap(λ) and chlorophyll a concentration are observed, with the determination coefficient r2 of 0.42. The relatively large scatter around ap(443) versus chl-a relationship would be attributed to the effects ofloading of the nonalgal particulate absorption. Our analysis indicated that such relationships similar to that for Case Ⅰ waters can be applicable to optically complex Case Ⅱ waters if the effects caused by nonalgal are corrected. The chlorophyll-specific absorption coefficients of phytoplankton pigment are not constant, it

  14. Mandibular lateral incisor-canine transposition, concomitant dental anomalies, and genetic control.

    Science.gov (United States)

    Peck, S; Peck, L; Kataja, M

    1998-10-01

    Mandibular lateral incisor-canine (Mn.I2.C) transposition is a rare developmental disturbance of tooth order characterized by positional interchange of the two teeth. In children with Mn.I2.C anomaly, the mandibular lateral incisor shows distal ectopic eruption and the adjacent canine subsequently erupts mesial to it. A sample of 60 orthodontic patients with Mn.I2.C transposition was studied using roentgenograms taken at the time of diagnosis. Two age-related phenotypes of the anomaly were identified: early-stage (median age, 9 years) and mature-stage (median age, 12 years). Mn.I2.C transposition occurred bilaterally in 10 subjects (17%) and favored female expression (sex ratio, M1:F3) and right-side occurrence (68% of unilateral cases). Statistically significant associations were found between Mn.I2.C transposition and increased frequency of tooth agenesis (M3, p position probably caused by genetic influences. The Mn.I2.C anomaly likely results from genetic mechanisms similar to those responsible for occurrences of its associated dental anomalies, such as tooth agenesis and peg-shaped maxillary lateral incisors. In an appendix, clinical orthodontic management of Mn.I2.C transposition is discussed, based on treatment data derived from the study sample.

  15. The DNA-bending protein HMGB1 is a cellular cofactor of Sleeping Beauty transposition.

    Science.gov (United States)

    Zayed, Hatem; Izsvák, Zsuzsanna; Khare, Dheeraj; Heinemann, Udo; Ivics, Zoltán

    2003-05-01

    Sleeping Beauty (SB) is the most active Tc1/ mariner-type transposon in vertebrates. SB contains two transposase-binding sites (DRs) at the end of each terminal inverted repeat (IR), a feature termed the IR/DR structure. We investigated the involvement of cellular proteins in the regulation of SB transposition. Here, we establish that the DNA-bending, high-mobility group protein, HMGB1 is a host-encoded cofactor of SB transposition. Transposition was severely reduced in mouse cells deficient in HMGB1. This effect was rescued by transient over-expression of HMGB1, and was partially complemented by HMGB2, but not with the HMGA1 protein. Over-expression of HMGB1 in wild-type mouse cells enhanced transposition, indicating that HMGB1 can be a limiting factor of transposition. SB transposase was found to interact with HMGB1 in vivo, suggesting that the transposase may recruit HMGB1 to transposon DNA. HMGB1 stimulated preferential binding of the transposase to the DR further from the cleavage site, and promoted bending of DNA fragments containing the transposon IR. We propose that the role of HMGB1 is to ensure that transposase-transposon complexes are first formed at the internal DRs, and subsequently to promote juxtaposition of functional sites in transposon DNA, thereby assisting the formation of synaptic complexes.

  16. Laparoscopic ovarian transposition before pelvic radiation in rectal cancer patient: safety and feasibility

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    Al-Asari Sami

    2012-09-01

    Full Text Available Abstract Background Infertility due to pelvic radiation for advanced rectal cancer treatment is a major concern particularly in young patients. Pre-radiation laparoscopic ovarian transposition may offer preservation of ovarian function during the treatment however its use is limited. Aim The study investigates the safety, feasibility and effectiveness of pre-radiation laparoscopic ovarian transposition and its effect on ovarian function in the treatment o locally advanced rectal cancer. Methods Charts review of all young female patients diagnosed with locally advanced rectal cancer, underwent laparoscopic ovarian transposition, then received preoperative radiotherapy at king Faisal Specialist Hospital and Research Centre between 2003–2007. Results During the period studied three single patients age between 21–27 years underwent pre-radiation laparoscopic ovarian transposition for advanced rectal cancer. All required pretreatment laparoscopic diversion stoma due to rectal stricture secondary to tumor that was performed at the same time. One patient died of metastatic disease during treatment. The ovarian hormonal levels (FSH and LH were normal in two patients. One has had normal menstrual period and other had amenorrhoea after 4 months follow-up however her ovarian hormonal level were within normal limits. Conclusions Laparoscopic ovarian transposition before pelvic radiation in advanced rectal cancer treatment is an effective and feasible way of preservation of ovarian function in young patients at risk of radiotherapy induced ovarian failure. However, this procedure is still under used and it is advisable to discuss and propose it to suitable patients.

  17. Base flipping in tn10 transposition: an active flip and capture mechanism.

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    Julien Bischerour

    Full Text Available The bacterial Tn5 and Tn10 transposases have a single active site that cuts both strands of DNA at their respective transposon ends. This is achieved using a hairpin intermediate that requires the DNA to change conformation during the reaction. In Tn5 these changes are controlled in part by a flipped nucleoside that is stacked on a tryptophan residue in a hydrophobic pocket of the transposase. Here we have investigated the base flipping mechanism in Tn10 transposition. As in Tn5 transposition, we find that base flipping takes place after the first nick and is required for efficient hairpin formation and resolution. Experiments with an abasic substrate show that the role of base flipping in hairpin formation is to remove the base from the DNA helix. Specific interactions between the flipped base and the stacking tryptophan residue are required for hairpin resolution later in the reaction. We show that base flipping in Tn10 transposition is not a passive reaction in which a spontaneously flipped base is captured and retained by the protein. Rather, it is driven in part by a methionine probe residue that helps to force the flipped base from the base stack. Overall, it appears that base flipping in Tn10 transposition is similar to that in Tn5 transposition.

  18. Simulating the Erosion and Sedimentation of Karun Alluvial River in the Region of Ahvaz (Southwest Of Iran

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    Farhang Azarang

    2015-07-01

    Full Text Available Since the rivers are the main basic and accessible resource of water for miscellaneous uses, the erosion and Sedimentation condition of rivers are of a great deal of importance. Karun River, the greatest river of Iran, has a considerable interest because of strategic and environmental conditions regarding its water projects planning, agriculture, water supply of cities, and industrial units. The morphological changes due to erosion processes, sedimentation, and Sediment transport affects the hydraulic structures like Intake port, irrigation systems, and pump stations. Thus, the present research deals with the simulation of erosion and sedimentation processes and also considering cross section geometric changes, prediction of river thalweg, and total sediment load of Karun River using HEC-RAS model. The simulation periods of this research is 10 years from 2001-2011. The results show that the Karun River has had sedimentation in its most cross sections while the erosion has been rarely observed. Additionally, the Englund–Hansen and Ackers–White sediment transport functions propose better results about the river changes. According to the HEC-RAS results and the measured data, river training of dredging is necessary at the studied site especially at the Ahvaz urban areas. Also, at the river parts which are under erosion the stabilization procedures for the banks and walls, is suggested. The result of this work can be an appropriate pattern about the situations of Karun and effects of erosion, sediment transport, and sedimentation processes.

  19. Distribution and mobility of mercury in soils of a gold mining region, Cuyuni river basin, Venezuela.

    Science.gov (United States)

    Santos-Francés, F; García-Sánchez, A; Alonso-Rojo, P; Contreras, F; Adams, M

    2011-04-01

    An extensive and remote gold mining region located in the East of Venezuela has been studied with the aim of assessing the distribution and mobility of mercury in soil and the level of Hg pollution at artisanal gold mining sites. To do so, soils and pond sediments were sampled at sites not subject to anthropological influence, as well as in areas affected by gold mining activities. Total Hg in regionally distributed soils ranged between 0.02 mg kg(-1) and 0.40 mg kg(-1), with a median value of 0.11 mg kg(-1), which is slightly higher than soil Hg worldwide, possibly indicating long-term atmospheric input or more recent local atmospheric input, in addition to minor lithogenic sources. A reference Hg concentration of 0.33 mg kg(-1) is proposed for the detection of mining affected soils in this region. Critical total Hg concentrations were found in the surrounding soils of pollutant sources, such as milling-amalgamation sites, where soil Hg contents ranged from 0.16 mg kg(-1) to 542 mg kg(-1) with an average of 26.89 mg kg(-1), which also showed high levels of elemental Hg, but quite low soluble+exchangeable Hg fraction (0.02-4.90 mg kg(-1)), suggesting low Hg soil mobility and bioavailability, as confirmed by soil column leaching tests. The vertical distribution of Hg through the soil profiles, as well as variations in soil Hg contents with distance from the pollution source, and Hg in pond mining sediments were also analysed.

  20. Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin

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    Christine A. Rumsey

    2015-09-01

    New hydrological insights for the region: Results suggest that approximately half of the streamflow in the UCRB is baseflow derived from groundwater discharge to streams. Higher baseflow yields typically occur in upper elevation areas of the UCRB. PCA identified precipitation, snow, sand content of soils, elevation, land surface slope, percent grasslands, and percent natural barren lands as being positively correlated with baseflow yield; whereas temperature, potential evapotranspiration, silt and clay content of soils, percent agriculture, and percent shrublands were negatively correlated with baseflow yield.

  1. Proximity to mosquito breeding habitat and Ross River virus risk in the Peel region of Western Australia.

    Science.gov (United States)

    Jardine, Andrew; Neville, Peter J; Lindsay, Michael D A

    2015-02-01

    It is intuitive that vector-borne disease exposure risk is related to proximity to sources of vector breeding, but this aspect rarely receives empirical testing. The population of Western Australia (WA) is increasing rapidly, with many new residential developments proposed in close proximity to mosquito breeding habitat. However, potential mosquito-borne disease risks for future residents are given little consideration by planning authorities. The Peel region is one of the fastest growing regions in WA and regularly experiences a large number of cases of the mosquito-borne Ross River virus (RRV) disease with epidemics occuring in the region every few years. A spatial analysis of RRV disease data in the Peel region was undertaken to determine the risk associated with proximity to a mosquito breeding habitat. Geographic Information Systems (GIS) software was used to create buffers between 1 and 6 km from the breeding habitat. The number of cases per 1000 dwellings in each buffer was calculated between 2002/03 to 2011/12 for years with >100 cases across all buffers (n=5) in addition to the cumulative rate over the entire period in each buffer. Residents living within 1 km of a mosquito breeding habitat had a significantly higher rate of RRV disease compared to the background rate across the Peel region in all individual years investigated. The cumulative data over the 10-year study period showed that residents in the 1- and 2-km buffers had a significantly higher rate, whereas those living between 3 and 6 km away did not. This study demonstrates an increased mosquito-borne disease risk associated with living in close proximity to a mosquito breeding habitat in a rapidly expanding region of WA and highlights the importance of considering mosquito-borne disease risks when planning authorities assess new residential development applications. Known mosquito breeding wetlands should be incorporated into land use planning scheme maps to ensure that they are accurately

  2. Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

    Science.gov (United States)

    Shu, Lei; Xie, Min; Wang, Tijian; Gao, Da; Chen, Pulong; Han, Yong; Li, Shu; Zhuang, Bingliang; Li, Mengmeng

    2016-12-01

    Severe high ozone (O3) episodes usually have close relations to synoptic systems. A regional continuous O3 pollution episode was detected over the Yangtze River Delta (YRD) region in China during 7-12 August 2013, in which the O3 concentrations in more than half of the cities exceeded the national air quality standard. The maximum hourly concentration of O3 reached 167.1 ppb. By means of the observational analysis and the numerical simulation, the characteristics and the essential impact factors of the typical regional O3 pollution are comprehensively investigated. The observational analysis shows that the atmospheric subsidence dominated by the western Pacific subtropical high plays a crucial role in the formation of high-level O3. The favorable weather conditions, such as extremely high temperature, low relative humidity and weak wind speed, caused by the abnormally strong subtropical high are responsible for the trapping and the chemical production of O3 in the boundary layer. In addition, when the YRD cities are at the front of Typhoon Utor, the periphery circulation of typhoon system can enhance the downward airflows and cause worse air quality. However, when the typhoon system weakens the subtropical high, the prevailing southeasterly surface wind leads to the mitigation of the O3 pollution. The integrated process rate (IPR) analysis incorporated in the Community Multi-scale Air Quality (CMAQ) model is applied to further illustrate the combined influence of subtropical high and typhoon system in this O3 episode. The results show that the vertical diffusion (VDIF) and the gas-phase chemistry (CHEM) are two major contributors to O3 formation. During the episode, the contributions of VDIF and CHEM to O3 maintain the high values over the YRD region. On 10-12 August, the cities close to the sea are apparently affected by the typhoon system, with the contribution of VDIF increasing to 28.45 ppb h-1 in Shanghai and 19.76 ppb h-1 in Hangzhou. In contrast, the cities

  3. Sources of C₂-C₄ alkenes, the most important ozone nonmethane hydrocarbon precursors in the Pearl River Delta region.

    Science.gov (United States)

    Zhang, Yanli; Wang, Xinming; Zhang, Zhou; Lü, Sujun; Huang, Zhonghui; Li, Longfeng

    2015-01-01

    Surface ozone is becoming an increasing concern in China's megacities such as the urban centers located in the highly industrialized and densely populated Pearl River Delta (PRD) region, where previous studies suggested that ozone production is sensitive to VOC emissions with alkenes being important precursors. However, little was known about sources of alkenes. Here we present our monitoring of ambient volatile organic compounds at four representative urban, suburban and rural sites in the PRD region during November-December 2009, which experienced frequent ozone episodes. C2-C4 alkenes, whose total mixing ratios were 11-20% of non-methane hydrocarbons (NMHCs) quantified, accounted for 38-64% of ozone formation potentials (OFPs) and 30-50% of the total hydroxyl radical (OH) reactivity by NMHCs. Ethylene was the most abundant alkene, accounting for 8-15% in total mixing ratios of NMHCs and contributed 25-46% of OFPs. Correlations between C2-C4 alkenes and typical source tracers suggested that ethylene might be largely related to vehicle exhausts and industry activities, while propene and butenes were much more LPG-related. Positive Matrix Factorization (PMF) confirmed that vehicle exhaust and liquefied petroleum gas (LPG) were two major sources that altogether accounted for 52-62%, 58-77%, 73-83%, 68-79% and 73-84% for ethylene, propene, 1-butene, trans-2-butene and cis-2-butene, respectively. Vehicle exhausts alone contributed 32-49% ethylene and 35-41% propene. Industry activities contributed 13-23% ethylene and 7-20% propene. LPG instead contributed the most to butenes (38-65%) and substantially to propene (23-36%). Extensive tests confirmed high fractions of propene and butenes in LPG then used in Guangzhou and in LPG combustion plumes; therefore, limiting alkene contents in LPG would benefit regional ozone control.

  4. Estimation of health and economic costs of air pollution over the Pearl River Delta region in China.

    Science.gov (United States)

    Lu, Xingcheng; Yao, Teng; Fung, Jimmy C H; Lin, Changqing

    2016-10-01

    The Pearl River Delta region (PRD) is the economic growth engine of China and also one of the most urbanized regions in the world. As a two-sided sword, rapid economic development causes air pollution and poses adverse health effects to the citizens in this area. This work estimated the negative health effects in the PRD caused by the four major ambient pollutants (SO2, NO2, O3 and PM10) from 2010 to 2013 by using a log linear exposure-response function and the WRF-CMAQ modeling system. Economic loss due to mortality and morbidity was evaluated by the value of statistical life (VSL) and cost of illness (COI) methods. The results show that the overall possible short-term all-cause mortality due to NO2, O3 and PM10 reached the highest in 2013 with the values being 13,217-22,800. The highest total economic loss, which ranged from 14,768 to 25,305million USD, occurred in 2013 and was equivalent to 1.4%-2.3% of the local gross domestic product. The monthly profile of cases of negative health effects varied by city and the types of ambient pollutants. The ratio of mortality attributed to air pollutants to total population was higher in urban areas than in rural areas. People living in the countryside should consider the possible adverse health effects of urban areas before they plan a move to the city. The results show that the health burden caused by the ambient pollutants over this region is serious and suggest that tighter control policies should be implemented in the future to reduce the level of air pollution.

  5. Impact of Precursor Levels and Global Warming on Peak Ozone Concentration in the Pearl River Delta Region of China

    Institute of Scientific and Technical Information of China (English)

    WEI Xiaolin; LIU Qian; Ka Se LAM; WANG Tijian

    2012-01-01

    The relationship between the emission of ozone precursors and the chemical production of tropospheric ozone (O3) in the Pearl River Delta Region (PRD) was studied using numerical simulation.The aim of this study was to examine the volatile organic compound (VOC)- or nitrogen oxide (NOx =NO+NO2)-limited conditions at present and when surface temperature is increasing due to global warming,thus to make recommendations for future ozone abatement policies for the PRD region.The model used for this application is the U.S.Environmental Protection Agency's (EPA's) third-generation air-quality modeling system; it consists of the mesoscale meteorological model MM5 and the chemical transport model named Community Multi-scale Air Quality (CMAQ).A series of sensitivity tests were conducted to assess the influence of VOC and NOx variations on ozone production.Tropical cyclone was shown to be one of the important synoptic weather patterns leading to ozone pollution.The simulations were based on a tropicalcyclone-related episode that occurred during 14-16 September 2004.The results show that,in the future,the control strategy for emissions should be tightened. To reduce the current level of ozone to meet the Hong Kong Environmental Protection Department (EPD) air-quality objective (hourly average of 120 ppb),emphasis should be put on restricting the increase of NOx emissions. Furthermore,for a wide range of possible changes in precursor emissions,temperature increase will increase the ozone peak in the PRD region; the areas affected by photochemical smog are growing wider,but the locations of the ozone plume are rather invariant.

  6. Detection and attribution of climate change at regional scale: case study of Karkheh river basin in the west of Iran

    Science.gov (United States)

    Zohrabi, Narges; Goodarzi, Elahe; Massah Bavani, Alireza; Najafi, Husain

    2016-09-01

    This research aims at providing a statistical framework for detection and attribution of climate variability and change at regional scale when at least 30 years of observation data are available. While extensive research has been done on detecting significant observed trends in hydroclimate variables and attribution to anthropogenic greenhouse gas emissions in large continents, less attention has been paid for regional scale analysis. The latter is mainly important for adaptation to climate change in different sectors including but not limited to energy, agriculture, and water resources planning and management, and it is still an open discussion in many countries including the West Asian ones. In the absence of regional climate models, an informative framework is suggested providing useful insights for policymakers. It benefits from general flexibility, not being computationally expensive, and applying several trend tests to analyze temporal variations in temperature and precipitation (gradual and step changes). The framework is implemented for a very important river basin in the west of Iran. In general, some increasing and decreasing trends of the interannual precipitation and temperature have been detected. For precipitation annual time series, a reducing step was seen around 1996 compared with the gradual change in most of the stations, which have not experience a dramatical change. The range of natural forcing is found to be ±76 % for precipitation and ±1.4 °C for temperature considering a two-dimensional diagram of precipitation and temperature anomalies from 1000-year control run of global climate model (GCM). Findings out of applying the proposed framework may provide useful insights into how to approach structural and non-structural climate change adaptation strategies from central governments.

  7. Identification of fish nursery areas in a free tributary of an impoundment region, upper Uruguay River, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Alves da Silva

    2012-01-01

    Full Text Available This study aims to determine the importance of different environments of the Ligeiro River (upper Uruguay River, Brazil in fish reproduction. For this purpose, three environments (sampling sites were selected: rapids, a pool, and the mouth of the Ligeiro River. Ichthyoplankton, zooplankton, and benthos were sampled six times per month from September, 2006 to March, 2007. Zooplankton and ichthyoplankton samples were collected early in the evening with plankton nets (64 µm and 500 µm, respectively. Benthos samples were also collected early in the evening with a Van Veen dredge. Local abiotic variables (temperature, dissolved oxygen, pH, electrical conductivity, water speed, alkalinity, water hardness, and water transparency were measured simultaneously with the biotic data sampling and were complemented by regional variables (water flow and precipitation. A total of 43,475 eggs and 2,269 larvae were captured. Of these larvae, 80.1% were in the pre-flexion and larval yolk stages. Digestive tract content showed that the greatest degree of repletion among the larvae in more advanced phases occurred in the pool environment. Water speed was the main characteristic used to differentiate the river's rapids and mouth from the pool. The abundance of zooplankton and benthos was not related to the distribution of densities among the different components of the ichthyoplankton. A greater abundance of eggs and larvae with yolk was found in the rapids and river mouth. Ordination analyses showed a connection between the advanced stage larvae and the pool environment. In conclusion, the rapids and river mouth of the Ligeiro River's are important locations for fish reproduction, particularly in regard to spawning and drifting of the ichthyoplankton's initial stages, whereas the pool represents a nursery place for larval growth.O presente estudo visa determinar a importância de diferentes ambientes do rio Ligeiro (alto rio Uruguai/Brasil na reprodução dos

  8. Remote Sensing-based Estimates of Potential Evapotranspiration for Hydrologic Modeling in the Upper Colorado River Basin Region

    Science.gov (United States)

    Barik, Muhammad Ghulam

    Potential Evapotranspiration (PET) is used as a common input to calculate evaporative demand in hydrological, ecological and biological modeling. Dynamic and distributed measurement of PET is important for improved hydrologic predictions at the watershed scale since PET varies with time and space. In this work, an advanced dynamic PET estimation is proposed by integrating geostationary satellite products into a currently existing remote sensing-based PET algorithm and evaluated in the framework of operational hydrologic forecasting modeling. The development work is approached through a series of studies. At first, a previously developed Moderate Resolution Imaging Spectroradiometer (MODIS) based PET (MODIS-PET) product applied over several flux towers and basins in the Upper Colorado River Basin (UCRB) to determine its applicability and predictive ability in comparison to other ground based distributed PET methods. Results from this primary study indicate the MODIS-PET is an improved PET estimation method compared to the other two contemporary distributed PET products that were tested over this geographically complex study region. In addition to elevation and cloud cover, uncertainties are associated with the MODIS-PET algorithm pertaining from three model variables; land surface temperature, air temperature and surface emissivity. The crude hypothetical sinusoidal curve considered in the conversion of instantaneous MODIS-PET to the daily PET estimation can potentially be replaced with satellite data with improved temporal resolution. Hence, integration of Geostationary Operational Environmental Satellites (GOES), a series of geostationary satellites with frequent observations, data in the MODIS-PET algorithm is performed in the second part. The coupling of GOES within the MODIS-PET algorithm shows significant improvement over the previously developed stand-alone MODIS-PET product, especially for cloudy days and high temperature pixels. Finally, evaluation of these

  9. Element Geochemical Division of the Middle Segment of the Sanjiang(Three-River) Region

    Institute of Scientific and Technical Information of China (English)

    沈上越; 魏启荣; 莫宣学; 喻学惠; 曾普盛; 胡长寿

    2001-01-01

    This paper describes the aim and principle of element geochemical division, the source of samples and data processing, the choice of divisional indices and the division of index value ranges. According to the geological structures and characteristic values (the accumulated value of enrichment coefficient) of the mantle-type elements (KT) this region can be divided into seven geochemical zones, i.e., the Yangtze basement, the Yangtze cover, the Jinshajiang paleo-Tethys, the Lancangjiang paleo-Tethys, the Lanping Mesozoic basin, the Indosinian granite, and the Himalayan granite. Again in accordance with the different characteristic val ues of high field strength elements (HFSE) (KNb) or radiogenic elements (KTh) 16 geochemi cal sub-zones can be divided. Meanwhile, this paper also discusses the rules of variation in char acteristic value of the various sub-zones and points out the characteristics of enrichment of ore forming elements in some of the sub-zones.

  10. On the need for bias correction in regional climate scenarios to assess climate change impacts on river runoff

    Directory of Open Access Journals (Sweden)

    M. J. Muerth

    2013-03-01

    Full Text Available In climate change impact research, the assessment of future river runoff as well as the catchment-scale water balance is impeded by different sources of modeling uncertainty. Some research has already been done in order to quantify the uncertainty of climate projections originating from the climate models and the downscaling techniques, as well as from the internal variability evaluated from climate model member ensembles. Yet, the use of hydrological models adds another layer of uncertainty. Within the QBic3 project (Québec–Bavarian International Collaboration on Climate Change, the relative contributions to the overall uncertainty from the whole model chain (from global climate models to water management models are investigated using an ensemble of multiple climate and hydrological models. Although there are many options to downscale global climate projections to the regional scale, recent impact studies tend to use regional climate models (RCMs. One reason for that is that the physical coherence between atmospheric and land-surface variables is preserved. The coherence between temperature and precipitation is of particular interest in hydrology. However, the regional climate model outputs often are biased compared to the observed climatology of a given region. Therefore, biases in those outputs are often corrected to facilitate the reproduction of historic runoff conditions when used in hydrological models, even if those corrections alter the relationship between temperature and precipitation. So, as bias correction may affect the consistency between RCM output variables, the use of correction techniques and even the use of (biased climate model data itself is sometimes disputed among scientists. For these reasons, the effect of bias correction on simulated runoff regimes and the relative change in selected runoff indicators is explored. If it affects the conclusion of climate change analysis in hydrology, we should consider it as a source

  11. An approach to the age of Huanghe River in shelf regions of Yellow Sea and Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    YU Hongjun; XU Xingyong; LI Guanbao

    2005-01-01

    There are two different opinions on the formation history of Huanghe (Yellow) River. One postulates that Huanghe River might have come into existence before Tertiary. The other supposes that it joined up into a long river only in the last stage of Late Pleistocene. The appearance of Huanghe River is believed to have close relation to the uplifting of Tibetan Plateau. It is not likely that it could have come into being before its high elevation riverhead was formed. Today Huanghe River occurred probably during the recession of the sea in glacial periods. In the last glacial age, the climate was very harsh in the area north of the modern estuary of Changjiang (Yangtse) River; some areas were permafrost and the others barren deserts. At that time, eolation was the major exogenic force on exposed shelf. Beginning from 12 Ka BP, the global climate warmed up, resulting in gradual disappearance of continental mountain glaciers retreated, and sea level rose. Consequently, Huanghe River was replenished with water to become modern river system. With continued rising of sea level, Huanghe River delta moved continuously eastward.

  12. The impact of synoptic circulation on air quality and pollution-related human health in the Yangtze River Delta region.

    Science.gov (United States)

    Liao, Zhiheng; Gao, Meng; Sun, Jiaren; Fan, Shaojia

    2017-12-31

    PM2.5 and O3 pollution are of concern for the Yangtze River Delta (YRD) region due to their adverse impact on human health. In conjunction with a complex distribution of emission sources, the synoptic circulation conditions control the temporal and spatial variability of air pollution levels and hence the pollution-related health burdens. In this study, a long-term synoptic circulation catalogue is developed by applying the automated Lamb weather type method to the ECMWF mean sea level pressure reanalysis for the YRD region during 2013-2016. Ten typical circulation types are examined in relation to the transport pathways and diffusion conditions, and then multi-site surface observations of PM2.5 and O3 are composited for different circulation conditions. The results show that each circulation type is characterized with distinct air mass origin, diffusion condition and air quality level. The anticyclonic type (Type A) corresponds to the highest regional PM2.5 concentration (68.5μg/m(3)) due to the subsidence flow and long-range transport, while the westerly types (Types SW, W and NW) correspond to the higher regional maximum daily 8-h running average O3 (MDA8 O3) concentration (>100μg/m(3)) due to favorable local meteorological conditions. Regional transport causes an east-high and west-low PM2.5 distribution in westerly types but a west-high and east-low PM2.5 distribution in easterly types (Types SE, E and NE). In contrast, nearly all the types show an east-high and west-low O3 distribution, suggesting the predominated impacts of precursor emissions. By using established exposure-response functions, the health impact assessment (HIA) shows that Type W poses the greatest public health risk with mean daily excess mortality of 77.3 (95% CI: 61.9, 92.6) deaths and O3 pollution accounts for approximately 70% of this health burden. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. [Mobile genetic element MDG4 (gypsy) in Drosophila melanogaster. Features of structure and regulation of transposition].

    Science.gov (United States)

    Kusulidu, L K; Karpova, N N; Razorenova, O V; Glukhov, I A; Kim, A I; Liubomirskaia, N V; Il'in, Iu V

    2001-12-01

    Distribution of two structural functional variants of the MDG4 (gypsy) mobile genetic element was examined in 44 strains of Drosophila melanogaster. The results obtained suggest that less transpositionally active MDG4 variant is more ancient component of the Drosophila genome. Using Southern blotting, five strains characterized by increased copy number of MDG4 with significant prevalence of the active variant over the less active one were selected for further analysis. Genetic analysis of these strains led to the suggestion that some of them carry factors that mobilize MDG4 independently from the cellular flamenco gene known to be responsible for transposition of this element. Other strains probably contained a suppressor of the flam- mutant allele causing active transpositions of the MDG4. Thus, the material for studying poorly examined relationships between the retrovirus and the host cell genome was obtained.

  14. CUBITAL TUNNEL SYNDROME: REVIEW OF 14 ANTERIOR SUBCUTANEOUS TRANSPOSITIONS OF THE VASCULARIZED ULNAR NERVE

    Directory of Open Access Journals (Sweden)

    M. Farzan

    2005-06-01

    Full Text Available Anterior transposition of the ulnar nerve is widely implemented for treatment of cubital tunnel ‎syndrome. However, preservation of the extrinsic blood supply of the ‎ulnar nerve may result in better clinical outcomes. Fourteen patients with cubital tunnel ‎syndrome, 11 ‎men and 3 women, were treated by anterior subcutaneous transposition of the ulnar nerve. The extrinsic blood supply of the ulnar nerve was ‎preserved. The average age at the time of operation was 33 years. The average follow-up period was 44 months. Post-operative outcome assessment by an independent examiner was based on the modified Bishop rating system. Nine patients had excellent or good outcomes. Five patients had a fair outcome. There ‎were no complications or recurrence of symptoms. Anterior subcutaneous ‎transposition of the vascularized ulnar nerve is an effective method of surgical ‎treatment for patients with cubital tunnel syndrome.

  15. Dental transposition of canine and lateral incisor and impacted central incisor treatment: A case report

    Directory of Open Access Journals (Sweden)

    Tarcisio Jacinto Gebert

    2014-01-01

    Full Text Available INTRODUCTION: Dental transposition and impaction are disorders related to ectopic eruption or failure in tooth eruption, which can affect child physical, mental and social development and may be difficult to be clinically solved. METHODS: We describe a case of transposition between the upper left canine and lateral incisor associated with impaction of the central incisor on the same side, in a 12-year-old patient. Conservative treatment involving surgical-orthodontic correction of transposed teeth and traction of the central incisor was conducted. CONCLUSION: The option of correcting transposition and orthodontic traction by means of the segmented arch technique with devices such as cantilever and TMA rectangular wire loops, although a complex alternative, was proved to be esthetically and functionally effective.

  16. Ecological function regionalization of fluvial corridor landscapes and measures for ecological regeneration in the middle and lower reaches of the Tarim River,Xinjiang of China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The middle and lower reaches of the Tarim River are currently one of the main regions of ecological restoration in the arid areas of western China.Using the principles and method of landscape ecology,this study has chosen the fluvial corridor landscape in the middle and lower reaches of the Tarim River,and discusses the region’s ecologically functional regionalization system and issues related to its practical classification.On this basis the corresponding regionalizing principles and standards were developed which were used to qualitatively divide the three main landscapes as the ecologically functional areas in the drainage basin.The paper has also analyzed the characteristic of the study areas,and has put forward the measures for its ecological restoration.

  17. Derepression of the plant Chromovirus LORE1 induces germline transposition in regenerated plants.

    Directory of Open Access Journals (Sweden)

    Eigo Fukai

    2010-03-01

    Full Text Available Transposable elements represent a large proportion of the eukaryotic genomes. Long Terminal Repeat (LTR retrotransposons are very abundant and constitute the predominant family of transposable elements in plants. Recent studies have identified chromoviruses to be a widely distributed lineage of Gypsy elements. These elements contain chromodomains in their integrases, which suggests a preference for insertion into heterochromatin. In turn, this preference might have contributed to the patterning of heterochromatin observed in host genomes. Despite their potential importance for our understanding of plant genome dynamics and evolution, the regulatory mechanisms governing the behavior of chromoviruses and their activities remain largely uncharacterized. Here, we report a detailed analysis of the spatio-temporal activity of a plant chromovirus in the endogenous host. We examined LORE1a, a member of the endogenous chromovirus LORE1 family from the model legume Lotus japonicus. We found that this chromovirus is stochastically de-repressed in plant populations regenerated from de-differentiated cells and that LORE1a transposes in the male germline. Bisulfite sequencing of the 5' LTR and its surrounding region suggests that tissue culture induces a loss of epigenetic silencing of LORE1a. Since LTR promoter activity is pollen specific, as shown by the analysis of transgenic plants containing an LTR::GUS fusion, we conclude that male germline-specific LORE1a transposition in pollen grains is controlled transcriptionally by its own cis-elements. New insertion sites of LORE1a copies were frequently found in genic regions and show no strong insertional preferences. These distinctive novel features of LORE1 indicate that this chromovirus has considerable potential for generating genetic and epigenetic diversity in the host plant population. Our results also define conditions for the use of LORE1a as a genetic tool.

  18. Situs inversus with levocardia and congenitally corrected transposition of great vessels with rheumatic tricuspid valve stenosis and regurgitation

    Directory of Open Access Journals (Sweden)

    Bharat B Kukreti

    2011-01-01

    Full Text Available Congenitally corrected transposition of great arteries is a rare congenital anomaly. This case report describes a 30-year-old patient of congenitally corrected transposition of the great arteries with rheumatic involvement of systemic (tricuspid atrio-ventricular valve.

  19. Yellow River, Cradle of China

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    THE Yellow River is the Mother River of China. In the hearts of the Chinese people, it is not just an ancient river measuring 4,845 kilometers long that passes through nine provinces and regions, but also a symbol. The poets say that the waterway is the image of ancient China. Thephilosophers say the river is the shadow of a dragon. The river

  20. Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern China

    Institute of Scientific and Technical Information of China (English)

    WANG; Jian; LI; Shuo

    2006-01-01

    Climatic change has significant impacts on snow cover in mid-latitude mountainous regions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are considered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2001. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

  1. Mapping Social Vulnerability to Air Pollution: A Case Study of the Yangtze River Delta Region, China

    Directory of Open Access Journals (Sweden)

    Yi Ge

    2017-01-01

    Full Text Available Many frequent and severe air pollution incidents have emerged across the vast parts of China recently. The identification of factors and mapping social vulnerability has become extremely necessary for environmental management and sustainable development. However, studies associating social vulnerability with air pollution remain sparse. With reference to research achievements of social vulnerability, this study made a new trial regarding social vulnerability assessment to air pollution. With the projection pursuit cluster (PPC model, the top three factors contributing to social vulnerability index (SVI were discovered and SVI and SVI dimensions (susceptibility, exposure, and adaptability were evaluated. Results revealed that adaptability values are higher than susceptibility and exposure values. SVI is in a poor condition as, for the whole region, most values belong to the high-medium level. High SVI values mainly appear in the northern and the southern ends of study area. SVI in Shanghai is lower than in Jiangsu and Zhejiang provinces. On the scale of prefecture-level city, it can be found that the low-value centers of SVI always occurred in urban core areas. The spatial variation and inequality in social vulnerability provide policy-makers a scientific basis for air pollution prevention and sustainable management.

  2. Variable transposition of eight maize activator (ac) elements located on the short arm of chromosome 1.

    Science.gov (United States)

    Sheridan, William F

    2011-09-01

    Eight Activator (Ac) transposable elements mapped to the maize chromosome arm 1S were assessed for Ac transposition rates. For each of the Ac stocks, plants homozygous for the single Ac element and the Ds reporter r1-sc:m3 on chromosome 10 were crossed as females by a homozygous r1-sc:m3 tester color-converted W22 line. The resulting ears produced mostly coarsely spotted kernels and a low frequency of either near-colorless fine-spotted kernels or nonspotted kernels. The relative frequency of these two types of near-colorless kernels differed among the eight Ac stocks. The extent to which increased Ac dosage results in nonspotted kernels may be Ac-specific. Although all of the Ac elements are in near-isogenic inbred W22 lines, they varied to a large extent in their transposition frequency. These differences might possibly result from structural differences among the Ac elements. Because one pair of Ac elements derived from Ac33 on chromosome arm 5S differed about 13-fold in transposition frequency and a second pair of Ac elements derived from Ac12 on chromosome arm 1S differed about 3-fold in transposition frequency, this is not a likely explanation for all eight Ac elements. The data presented here support the notion that the differences in transposition frequency of the eight Ac elements may be a reflection of variability in Ac transcription or accessibility of the transposase to the Ac element, resulting from differences in the chromatin environments wherein the Ac elements are located. This is the first report of variability in transposition rates among different Ac donor lines.

  3. Water Quality Index (WQI) of Jaguari and Atibaia Rivers in the region of Paulínia, São Paulo, Brazil.

    Science.gov (United States)

    Ramos, Marcio Antonio Gomes; de Oliveira, Eduardo Schneider Bueno; Pião, Antonio Carlos Simões; Leite, Dilza Aparecida Nalin de Oliveira; de Angelis, Dejanira de Franceschi

    2016-05-01

    Due to the concern with the quality of hydric resources, the monitoring is essential to evaluate and identify the anthropogenic and environmental interferences in a quantitative and qualitative level. In order to assist the interpretation of the water status of hydric bodies, the gathering of analytical data often considers the Water Quality Index (WQI). This index transforms technical information in description of the water quality status, highlighting the effectiveness of its use and guiding the decision-making process when necessary. The aim of this research is to assess the water quality of a region in São Paulo State, Brazil, by means of the WQI of Jaguari and Atibaia Rivers. The period of intense drought, which affected the Brazilian southeast in 2014, was evaluated and compared to the mean values recorded from October 2009 to March 2015, correlating the values of Escherichia coli and the biochemical oxygen demand (BOD). One hundred nine samples were collected, being 53 from dry seasons, between October and March, and 56 from rainy seasons, between April and September. The WQIs in Jaguari and Atibaia Rivers, during dry season, were of 42.2 (medium) and 36.7 (bad), respectively. The same pattern was registered for the dry season, for both rivers, with indices values of 40.1 for Jaguari River (medium) and 34.9 for Atibaia River (bad). This research presented the need of an effective evaluation of the environmental quality and preservation by competent organs for both rivers. Due to the detected conditions, special attention should be given to the Atibaia River.

  4. Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

    Science.gov (United States)

    Fullerton, Aimee H.; Torgersen, Christian; Lawler, Joshua J.; Faux, Russell N.; Steel, E. Ashley; Beechie, Timothy J.; Ebersole, Joseph L.; Leibowitz, Scott J.

    2015-01-01

    Prevailing theory suggests that stream temperature warms asymptotically in a downstream direction, beginning at the temperature of the source in the headwaters and leveling off downstream as it converges to match meteorological conditions. However, there have been few empirical examples of longitudinal patterns of temperature in large rivers due to a paucity of data. We constructed longitudinal thermal profiles (temperature versus distance) for 53 rivers in the Pacific Northwest (USA) using an extensive dataset of remotely sensed summertime river temperatures and classified each profile into one of five patterns of downstream warming: asymptotic (increasing then flattening), linear (increasing steadily), uniform (not changing), parabolic (increasing then decreasing), or complex (not fitting other classes). We evaluated (1) how frequently profiles warmed asymptotically downstream as expected, and (2) whether relationships between river temperature and common hydroclimatic variables differed by profile class. We found considerable diversity in profile shape, with 47% of rivers warming asymptotically, and 53% having alternative profile shapes. Water temperature did not warm substantially over the course of the river for coastal parabolic and uniform profiles, and for some linear and complex profiles. Profile classes showed no clear geographical trends. The degree of correlation between river temperature and hydroclimatic variables differed among profile classes, but there was overlap among classes. Water temperature in rivers with asymptotic or parabolic profiles was positively correlated with August air temperature, tributary temperature and velocity, and negatively correlated with elevation, August precipitation, gradient, and distance upstream. Conversely, associations were less apparent in rivers with linear, uniform, or complex profiles. Factors contributing to the unique shape of parabolic profiles differed for coastal and inland rivers, where downstream cooling

  5. Allegheny County Major Rivers

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  6. The forecasting research of early warning systems for atmospheric pollutants: A case in Yangtze River Delta region

    Science.gov (United States)

    Song, Yiliao; Qin, Shanshan; Qu, Jiansheng; Liu, Feng

    2015-10-01

    The issue of air quality regarding PM pollution levels in China is a focus of public attention. To address that issue, to date, a series of studies is in progress, including PM monitoring programs, PM source apportionment, and the enactment of new ambient air quality index standards. However, related research concerning computer modeling for PM future trends estimation is rare, despite its significance to forecasting and early warning systems. Thereby, a study regarding deterministic and interval forecasts of PM is performed. In this study, data on hourly and 12 h-averaged air pollutants are applied to forecast PM concentrations within the Yangtze River Delta (YRD) region of China. The characteristics of PM emissions have been primarily examined and analyzed using different distribution functions. To improve the distribution fitting that is crucial for estimating PM levels, an artificial intelligence algorithm is incorporated to select the optimal parameters. Following that step, an ANF model is used to conduct deterministic forecasts of PM. With the identified distributions and deterministic forecasts, different levels of PM intervals are estimated. The results indicate that the lognormal or gamma distributions are highly representative of the recorded PM data with a goodness-of-fit R2 of approximately 0.998. Furthermore, the results of the evaluation metrics (MSE, MAPE and CP, AW) also show high accuracy within the deterministic and interval forecasts of PM, indicating that this method enables the informative and effective quantification of future PM trends.

  7. Spatial modeling of the geographic distribution of wildlife populations: A case study in the lower Mississippi River region

    Science.gov (United States)

    Ji, W.; Jeske, C.

    2000-01-01

    A geographic information system (GIS)-based spatial modeling approach was developed to study environmental and land use impacts on the geographic distribution of wintering northern pintails (Arias acuta) in the Lower Mississippi River region. Pintails were fitted with backpack radio transmitter packages at Catahoula Lake, LA, in October 1992-1994 and located weekly through the following March. Pintail survey data were converted into a digital database in ARC/INFO GIS format and integrated with environmental GIS data through a customized modeling interface. The study verified the relationship between pintail distributions and major environmental factors and developed a conceptual relation model. Visualization-based spatial simulations were used to display the movement patterns of specific population groups under spatial and temporal constraints. The spatial modeling helped understand the seasonal movement patterns of pintails in relation to their habitat usage in Arkansas and southwestern Louisiana for wintering and interchange situations among population groups wintering in Texas and southeastern Louisiana. (C) 2000 Elsevier Science B.V.

  8. Quebec region's shoreline segmentation in the St. Lawrence River : response tool for oil spills

    Energy Technology Data Exchange (ETDEWEB)

    Laforest, S. [Environment Canada, Montreal, PQ (Canada). Quebec Region; Boule, M. [Canadian Coast Guard, Quebec City, PQ (Canada); Martin, V. [Eastern Canada Response Corp., Vercheres, PQ (Canada)

    2004-07-01

    Environment Canada, the Canadian Coast Guard, and the Eastern Canada Response Corporation are developing and refining pre-spill databases containing information about physical shoreline characteristics. Automated links between these pre-spill shoreline characteristic databases and computerized shoreline assessment tools have also been created using Geographical Information System (GIS) technology. The pre-spill databases can be used for planning shoreline cleanup operations. A training exercise, designed to evaluate a spill management system integrating the Quebec region pre-spill shoreline database and the ShoreAssess{sup R} shoreline assessment system was performed by Eastern Canada Response Corporation during an aerial survey where shoreline was segmented into digitized information. The cartography of segmentation covers the fluvial part of the St. Lawrence River. The oil spill-oriented database includes geomorphologic information from the supratidal to the lower intertidal zones. It also includes some statistical information and other requirements for cleanup operations. The computerized shoreline assessment tools made it possible to evaluate the length and type of shoreline that would potentially be impacted by oil. The tools also made it possible to assess the shoreline treatment methods most likely to be used, and evaluate the probable duration of the cleanup operation. The training exercise demonstrated that the integration of the databases is a valuable tool during the early phases of an oil spill response. 9 refs., 3 figs.

  9. Research on Nonpoint Source Pollution Assessment Method in Data Sparse Regions: A Case Study of Xichong River Basin, China

    Directory of Open Access Journals (Sweden)

    Xing Liu

    2015-01-01

    Full Text Available The NPS pollution is difficult to manage and control due to its complicated generation and formation mechanism, especially in the data sparse area. Thus the ECM and BTOPMC were, respectively, adopted to develop an easy and practical assessment method, and a comparison between the outputs of them is then conducted in this paper. The literature survey and field data were acquired to confirm the export coefficients of the ECM, and the loads of TN and TP were statistically analyzed in the study area. Based on hydrological similarity, runoff data from nearby gauged sites were pooled to compensate for the lack of at-site data and the water quality submodel of BTOPMC was then applied to simulate the monthly pollutant fluxes in the two sections from 2010 to 2012. The results showed agricultural fertilizer, rural sewage, and livestock and poultry sewage were the main pollution sources, and under the consideration of self-purification capacity of river, the outputs of the two models were almost identical. The proposed method with a main thought of combining and comparing an empirical model and a mechanistic model can assess the water quality conditions in the study area scientifically, which indicated it has a good potential for popularization in other regions.

  10. Pollution of intensively managed greenhouse soils by nutrients and heavy metals in the Yellow River Irrigation Region, Northwest China.

    Science.gov (United States)

    Kong, Xiaole; Cao, Jing; Tang, Rangyun; Zhang, Shengqiang; Dong, Fang

    2014-11-01

    The present study aimed to assess the potential ecological risk of heavy metals and nutrient accumulation in polytunnel greenhouse soils in the Yellow River irrigation region (YRIR), Northwest China, and to identify the potential sources of these heavy metals using principal component analysis. Contents of available nitrogen (AN), phosphorus (AP), and potassium (AK) in the surface polytunnel greenhouse soils (0-20 cm) varied from 13.42 to 486.78, from 39.10 to 566.97, and from 21.64 to 1,156.40 mg kg(-1), respectively, as well as AP, soil organic matter (SOM) and AK contents tended to increase significantly at the 0-20- and 20-40-cm soil layers. Heavy metal accumulations occurred in the polytunnel greenhouse soils as compared to arable soils, especially at a depth of 20 cm where Cd, Zn and Cu contents were significantly higher than arable soil. Cd and As were found to be the two main polluting elements in the greenhouse soils because their contents exceeded the thresholds established for greenhouse vegetable production HJ333-2006 in China and the background of Gansu province. It has been shown that Cd, Cu, Pb and Zn at the 0-20-cm soil layer were derived mainly from agricultural production activities, whereas contents of Cr and Ni at the same soil layer were determined by 'natural' factors and As originated from natural sources, deposition and irrigation water.

  11. Impacts of climate change on water resources in source regions of Yangtze River and Yellow River%气候变化对长江、黄河源区水资源的影响

    Institute of Scientific and Technical Information of China (English)

    白路遥; 荣艳淑

    2012-01-01

    The characteristics of the climate in the source regions of the Yangtze River and Yellow River were analyzed based on the monthly precipitation and monthly mean temperature at 22 meteorological stations from 1961 to 2010. The difference in the value between precipitation and evaporation was used to represent the water resources, in order to analyze the impacts of climate change on the water resources. The results show that the precipitation, temperature, and evaporation in the source regions of the Yangtze River and Yellow River have changed significantly, especially in the last 20 years, when there were significant increasing trends in these properties. The water resources presented a fluctuating variation in the source region of the Yellow River and increased significantly in the last 10 years in the source region of the Yangtze River. The increase of precipitation can directly lead to the increase of water resources; however, the increasing temperature can lead to high evaporation that would consume more water resources. Therefore, the influences on water resources can be balanced out by the changes of precipitation and temperature, which explains why there is no significant change in the water resources in the source region of the Yellow River. The temperature increased significantly in the last 10 years in the source region of the Yangtze River, causing more glaciers to melt and water resources to increase in the region.%利用1961-2010年长江、黄河源区22个气象站的月降水量和月平均气温资料,分析长江、黄河源区的气候特征,用降水与蒸发的差值作为水资源量的代表,分析了气候变化对水资源的影响.结果表明,长江源区和黄河源区降水、气温和蒸发都有明显变化,尤其是近20年有明显增加趋势,但是两个源区的变化并不一致,黄河源区水资源量一直呈波动变化,而长江源区在最近10多年水资源量有明显增多现象.降水增多可直接增加水资源量,

  12. Nuclear and Related Analytical Techniques Used to Study the Anthropogenic Impact on the Sister River in the Vicinity of the Town of Klin (Moscow Region, Russia)

    CERN Document Server

    Morzhukhina, S V; Chermnykh, L P; Khodakovsky, L P; Frontasyeva, M V; Gundorina, S F

    2001-01-01

    The ecological fate of small rivers, tributaries of the Volga River, is of great concern in the national program of the Russian Federation "Restoration of the Volga River". The results on the elaborated hydrochemical and saprobiological water examination of the Sister River are reported along with the results on the multielement chemical analysis of surface sediments in the catchment of the town of Klin (Moscow Region) known for its numerous industrial and chemical enterprises with heavy contaminant inputs. Epithermal neutron activation analysis was used to study heavy metals and other toxic elements in bottom sediments. A total of 42 elements including Pb, Cu, Cd and Hg were determined by polarography (method of inverse voltamperometry). Metal/Al rations which express the relative mobility of the elements follow the sequence: Fe > Mg > K > Na > Ca >> Zr > Mn > Zn = Sr > Cr > V > Ni = As > Co. Elevated concentrations of Cd, Pb, Zn and Cu in the bottom sediments of the Sister River reinforced us to determine t...

  13. Biphilic Organophosphorus Catalysis: Regioselective Reductive Transposition of Allylic Bromides via PIII/PV Redox Cycling

    Science.gov (United States)

    Reichl, Kyle D.; Dunn, Nicole L.; Fastuca, Nicholas J.; Radosevich, Alexander T.

    2016-01-01

    We report that a regioselective reductive transposition of primary allylic bromides is catalyzed by a biphilic organophosphorus (phosphetane) catalyst. Spectroscopic evidence supports the formation of a pentacoordinate (σ5-P) hydridophosphorane as a key reactive intermediate. Kinetics experiments and computational modeling are consistent with a unimolecular decomposition of the σ5-P hydridophosphorane via a concerted cyclic transition structure that delivers the observed allylic transposition and completes a novel PIII/PV redox catalytic cycle. These results broaden the growing repertoire of reactions catalyzed within the PIII/PV redox couple and suggest additional opportunities for organophosphorus catalysis in a biphilic mode. PMID:25874950

  14. Weighted Genomic Distance Can Hardly Impose a Bound on the Proportion of Transpositions

    Science.gov (United States)

    Jiang, Shuai; Alekseyev, Max A.

    Genomic distance between two genomes, i.e., the smallest number of genome rearrangements required to transform one genome into the other, is often used as a measure of evolutionary closeness of the genomes in comparative genomics studies. However, in models that include rearrangements of significantly different "power" such as reversals (that are "weak" and most frequent rearrangements) and transpositions (that are more "powerful" but rare), the genomic distance typically corresponds to a transformation with a large proportion of transpositions, which is not biologically adequate.

  15. Nonuniform three-phase power lines: resonance effects due to conductor transposition

    Energy Technology Data Exchange (ETDEWEB)

    Brandao Faria, J.A.; Guerreiro das Neves, M.V. [Instituto Superior Tecnico, Lisbon (Portugal). Centro de Electrotecnia Teorica e Medidas Electricas

    2004-02-01

    This paper is concerned with nonuniform power line modelling. It deals with the resonance effects produced by conductor transposition in long overhead three-phase lines. A frequency- domain analysis is conducted showing that the modal propagation parameters characterising the transmission line structure exhibit a repetitive resonant behaviour for frequencies such that the overall transposition cycle length gets close to an integer multiple of one half wavelength. Consideration of these resonance phenomena is of major importance and should be taken into account in a variety of situations, for example, in power line carrier communications and line transient studies. (author)

  16. Management of labour and delivery in congenitally corrected transposition of great arteries.

    Science.gov (United States)

    Dhir, S; Racine, J; Gratton, R; Bergin, L; de Vrijer, B

    2015-11-01

    A descriptive case report of the labour and delivery management of a 28-year-old woman who presented with congenitally corrected transposition of great arteries, dextrocardia, systemic ventricular dysfunction and junctional tachycardia. Patients with congenitally corrected transposition have a thin-walled morphological right ventricle as the systemic circulatory pump. The stress of increased cardiac output can lead to congestive heart failure, systemic atrioventricular valve regurgitation and arrhythmias. We used minimally invasive continuous cardiac output monitoring, fluid balance optimization and good maternal pain control to prevent decompensation and achieve vaginal delivery with a good maternal and neonatal outcome. © 2015 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  17. Surrogate pregnancy in a patient who underwent radical hysterectomy and bilateral transposition of ovaries.

    Science.gov (United States)

    Azem, Foad; Yovel, Israel; Wagman, Israel; Kapostiansky, Rita; Lessing, Joseph B; Amit, Ami

    2003-05-01

    To evaluate IVF-surrogate pregnancy in a patient with ovarian transposition after radical hysterectomy for carcinoma of the cervix. Case report. A maternity hospital in Tel Aviv that is a major tertiary care and referral center. A 29-year-old woman who underwent Wertheim's hysterectomy for carcinoma of the uterine cervix and ovarian transposition before total pelvic irradiation. Standard IVF treatment, transabdominal oocyte retrieval, and transfer to surrogate mother. Outcome of IVF cycle. A twin pregnancy in the first cycle. This is the second reported case of controlled ovarian stimulation and oocyte retrieval performed on a transposed ovary.

  18. Regional-scale assessment of soil salinity in the Red River Valley using multi-year MODIS EVI and NDVI.

    Science.gov (United States)

    Lobell, D B; Lesch, S M; Corwin, D L; Ulmer, M G; Anderson, K A; Potts, D J; Doolittle, J A; Matos, M R; Baltes, M J

    2010-01-01

    The ability to inventory and map soil salinity at regional scales remains a significant challenge to scientists concerned with the salinization of agricultural soils throughout the world. Previous attempts to use satellite or aerial imagery to assess soil salinity have found limited success in part because of the inability of methods to isolate the effects of soil salinity on vegetative growth from other factors. This study evaluated the use of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in conjunction with directed soil sampling to assess and map soil salinity at a regional scale (i.e., 10-10(5) km(2)) in a parsimonious manner. Correlations with three soil salinity ground truth datasets differing in scale were made in Kittson County within the Red River Valley (RRV) of North Dakota and Minnesota, an area where soil salinity assessment is a top priority for the Natural Resource Conservation Service (NRCS). Multi-year MODIS imagery was used to mitigate the influence of temporally dynamic factors such as weather, pests, disease, and management influences. The average of the MODIS enhanced vegetation index (EVI) for a 7-yr period exhibited a strong relationship with soil salinity in all three datasets, and outperformed the normalized difference vegetation index (NDVI). One-third to one-half of the spatial variability in soil salinity could be captured by measuring average MODIS EVI and whether the land qualified for the Conservation Reserve Program (a USDA program that sets aside marginally productive land based on conservation principles). The approach has the practical simplicity to allow broad application in areas where limited resources are available for salinity assessment.

  19. Understanding Hydrological Regime Alterations Caused by dams: the Santiago River case in the Andean Region of the Amazon Basin.

    Science.gov (United States)

    Rosero-Lopez, D.; Flecker, A.; Walter, M. T.

    2016-12-01

    Water resources in South America have been clearly targeted as key sources for hydropower expansion over the next 30 years. Ecuador, among the most biologically diverse countries in the world, has the highest density of hydropower dams, either operational, under construction, or planned, in the Amazon Basin. Ecuador's ambitious plan to change its energy portfolio is conceived to satisfy the country's demand and to empower the country to be the region's first hydroelectric energy exporter. The Santiago watershed located in the southeast part of the country has 39 facilities either under construction or in operation. The Santiago River and its main tributaries (Zamora and Upano) are expected to be impounded by large dams over the next 10 years. In order to understand the magnitude and potential impacts of regional dam development on hydrological regimes, a 35-year historical data set of stream discharge was analyzed. We examined flow regimes for time series between the construction of each dam, starting with the oldest and largest built in 1982 up until the most recent dam built in 2005. Preliminary results indicate a systematic displacement in flow seasonality following post-dam compared to pre-dam conditions. There are also notable differences in the distributions of peaks and pulses in post-dam flows. The range of changes from these results shows that punctuated and cumulative impacts are related to the size of each new impoundment. These observations and their implications to the livelihoods, biota, and ecosystems services in the Santiago watershed need to be incorporated into a broader cost-benefit analysis of hydropower generation in the western Amazon Basin.

  20. Sensitivity of the weather research and forecasting model to parameterization schemes for regional climate of Nile River Basin

    Science.gov (United States)

    Tariku, Tebikachew Betru; Gan, Thian Yew

    2017-08-01

    Regional climate models (RCMs) have been used to simulate rainfall at relatively high spatial and temporal resolutions useful for sustainable water resources planning, design and management. In this study, the sensitivity of the RCM, weather research and forecasting (WRF), in modeling the regional climate of the Nile River Basin (NRB) was investigated using 31 combinations of different physical parameterization schemes which include cumulus (Cu), microphysics (MP), planetary boundary layer (PBL), land-surface model (LSM) and radiation (Ra) schemes. Using the European Centre for Medium-Range Weather Forecast (ECMWF) ERA-Interim reanalysis data as initial and lateral boundary conditions, WRF was configured to model the climate of NRB at a resolution of 36 km with 30 vertical levels. The 1999-2001 simulations using WRF were compared with satellite data combined with ground observation and the NCEP reanalysis data for 2 m surface air temperature (T2), rainfall, short- and longwave downward radiation at the surface (SWRAD, LWRAD). Overall, WRF simulated more accurate T2 and LWRAD (with correlation coefficients >0.8 and low root-mean-square error) than SWRAD and rainfall for the NRB. Further, the simulation of rainfall is more sensitive to PBL, Cu and MP schemes than other schemes of WRF. For example, WRF simulated less biased rainfall with Kain-Fritsch combined with MYJ than with YSU as the PBL scheme. The simulation of T2 is more sensitive to LSM and Ra than to Cu, PBL and MP schemes selected, SWRAD is more sensitive to MP and Ra than to Cu, LSM and PBL schemes, and LWRAD is more sensitive to LSM, Ra and PBL than Cu, and MP schemes. In summary, the following combination of schemes simulated the most representative regional climate of NRB: WSM3 microphysics, KF cumulus, MYJ PBL, RRTM longwave radiation and Dudhia shortwave radiation schemes, and Noah LSM. The above configuration of WRF coupled to the Noah LSM has also been shown to simulate representative regional

  1. Estimate of anthropogenic halocarbon emission based on measured ratio relative to CO in the Pearl River Delta region, China

    Science.gov (United States)

    Shao, M.; Huang, D.; Gu, D.; Lu, S.; Chang, C.; Wang, J.

    2011-05-01

    Using a GC/FID/MS system, we analyzed the mixing ratio of 16 halocarbon species in more than 100 air samples collected in 2004 from the Pearl River Delta (PRD) region of southern China. The results revealed that there are elevated mixing ratios for most of halocarbons, especially for HClC = CCl2 (trichloroethylene, TCE), CH2Cl2 (d