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Sample records for southern sudan implications

  1. Integrated Mapping of Neglected Tropical Diseases: Epidemiological Findings and Control Implications for Northern Bahr-el-Ghazal State, Southern Sudan

    PubMed Central

    Sturrock, Hugh J. W.; Picon, Diana; Sabasio, Anthony; Oguttu, David; Robinson, Emily; Lado, Mounir; Rumunu, John; Brooker, Simon; Kolaczinski, Jan H.

    2009-01-01

    Background There are few detailed data on the geographic distribution of most neglected tropical diseases (NTDs) in post-conflict Southern Sudan. To guide intervention by the recently established national programme for integrated NTD control, we conducted an integrated prevalence survey for schistosomiasis, soil-transmitted helminth (STH) infection, lymphatic filariasis (LF), and loiasis in Northern Bahr-el-Ghazal State. Our aim was to establish which communities require mass drug administration (MDA) with preventive chemotherapy (PCT), rather than to provide precise estimates of infection prevalence. Methods and Findings The integrated survey design used anecdotal reports of LF and proximity to water bodies (for schistosomiasis) to guide selection of survey sites. In total, 86 communities were surveyed for schistosomiasis and STH; 43 of these were also surveyed for LF and loiasis. From these, 4834 urine samples were tested for blood in urine using Hemastix reagent strips, 4438 stool samples were analyzed using the Kato-Katz technique, and 5254 blood samples were tested for circulating Wuchereria bancrofti antigen using immunochromatographic card tests (ICT). 4461 individuals were interviewed regarding a history of ‘eye worm’ (a proxy measure for loiasis) and 31 village chiefs were interviewed regarding the presence of clinical manifestations of LF in their community. At the village level, prevalence of Schistosoma haematobium and S. mansoni ranged from 0 to 65.6% and from 0 to 9.3%, respectively. The main STH species was hookworm, ranging from 0 to 70% by village. Infection with LF and loiasis was extremely rare, with only four individuals testing positive or reporting symptoms, respectively. Questionnaire data on clinical signs of LF did not provide a reliable indication of endemicity. MDA intervention thresholds recommended by the World Health Organization were only exceeded for urinary schistosomiasis and hookworm in a few, yet distinct, communities

  2. HIV-1 infection in Juba, southern Sudan.

    PubMed

    McCarthy, M C; Khalid, I O; El Tigani, A

    1995-05-01

    Thirty years of civil war in the Sudan have resulted in the isolation of the southern provinces which border Central and East Africa. Consequently, little is known about the epidemiology of HIV-1 infection in this region. To estimate the prevalence of HIV-1 infection in southern Sudan and the risk factors associated with disease transmission, a seroepidemiologic survey was conducted in the township of Juba. Study subjects invited to participate in this study included medical outpatients, inpatients hospitalized for active tuberculosis, and female prostitutes. A total of 401 subjects participated in the study. HIV-1 infection was confirmed in 25 subjects. The prevalence of HIV-1 infection was 19% (8/42) among tuberculosis patients, 16% (8/50) among prostitutes, and 3% (9/309) among outpatients. A significantly higher prevalence of HIV-1 infection was found among female prostitutes when compared to female outpatients: 16% (8/50) vs. 2% (4/178), P < 0.001. Correspondingly, the prevalence of seropositives was significantly higher among male outpatients reporting a history of sexual relations with prostitutes during the prior 10 years compared to male outpatients denying relations with prostitutes: 14% (5/37) vs. 0% (0/94), P = 0.0011. A history of a sexually transmitted disease (STD) was also associated with HIV-1 infection among male outpatients. The findings of this study indicate that HIV-1 infection is highly prevalent in southern Sudan and that prostitutes and their sexual partners represent a major reservoir of HIV infection in this population. This epidemiologic pattern resembles that seen in the African nations neighboring southern Sudan.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Sudan.

    PubMed

    1985-08-01

    The Sudan's population characteristics, geographical features, history, political conditions, and foreign relations are profiled. The 1984 population of Sudan has been estimated at 21.1 million, with an estimated annual growth rate of 3.0%. Approximately 25% of the Sudanese population resides in urban areas. Major religions are Islam, indigenous beliefs (in southern Sudan), and Christianity. The official language is Arabic, although English and tribal languages are also spoken. Education is compulsory for 9 years, but the attendance rate is only 48%. The infant mortality rate is 118.0/1000 live births, and life expectancy is 47 years. 78.4% of the work force is engaged in agriculture, 9.8% in industry and commerce, and 6% in government. The estimated gross national product for 1981-83 was $27.36 billion, with an estimated annual growth rate of 2.7% in 1982-83. Per capit income was approximately $361 in 1982, with an average annual inflation rate of 20-30%. Sudan's population is composed of 2 distinct cultures, Arab and black African, and effective collaboration between them poses one of the nation's principal internal problems. The 5 northern regions cover almost 2/3 of Sudan and include most urban centers. Most of the 13 million Sudanese who live in this area are Arabic-speaking Muslims of several distinct tribal groups. The southern region has a population of about 5.5 million and a predominantly rural, subsistence economy. The south also contains many tribal groups and uses many more languages than the north. Sudan's primary resources are agricultural. Although the country is trying to diversify its cash crops, cotton and cottonseed account for more than 50% of export earnings. Another large export crop is gum arabic. Grain sorghum is the principal food crop, and wheat is grown for domestic consumption. Livestock production has vast potential and many animals, particularly camels and sheep, are exported to other Arab countries. The inadequate transportation

  4. Viewing the Reconstruction of Primary Schooling in Southern Sudan through Education Data, 2006-2009

    ERIC Educational Resources Information Center

    Kim, HyeJin; Moses, Kurt D.; Jang, Bosun; Wils, Annababette

    2011-01-01

    After one of the longest wars in the history of Africa, Southern Sudan accomplished one of the world's quickest education reconstruction programmes. Once the Comprehensive Peace Agreement (CPA) was signed in 2005, the international donor community and the government and people of Southern Sudan united under a common goal: to increase access to…

  5. Collaborative Evaluation and Market Research Converge: An Innovative Model Agricultural Development Program Evaluation in Southern Sudan

    ERIC Educational Resources Information Center

    O'Sullivan, John M.; O'Sullivan, Rita

    2012-01-01

    In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A…

  6. Literacy in the Southern Sudan: A Case Study of Variables Affecting Literacy Programs.

    ERIC Educational Resources Information Center

    Cowan, J. Ronayne

    1983-01-01

    Describes the Local Languages Literacy Project in the Southern Sudan; delineates the most important educational, socioeconomic, and linguistic variables affecting the success of large-scale literacy programs in Africa; and questions the widely held assumption that indigenous language literacy is essential to subsequent literacy in the prestige…

  7. Collaborative evaluation and market research converge: an innovative model agricultural development program evaluation in Southern Sudan.

    PubMed

    O'Sullivan, John M; O'Sullivan, Rita

    2012-11-01

    In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A partnership of local officials, agricultural development staff, and students worked with the outside team to craft a survey of agricultural traders working between northern Uganda and Southern Sudan the steps approach of a collaborative model. The goal was to create a market directory of use to producers, government officials and others interested in stimulating agricultural trade. The directory of agricultural producers and distributors served as an agricultural development and promotion tool as did the collaborative process itself.

  8. Jebel Moya (Sudan): new dates from a mortuary complex at the southern Meroitic frontier.

    PubMed

    Brass, Michael; Schwenniger, Jean-Luc

    2013-12-01

    This paper proposes a new chronology for the burial complex at Jebel Moya, south-central Sudan. It reassesses the body of evidence from Sir Henry Wellcome's original 1911-1914 excavations in order to place the site within a firm chronological framework by: (a) applying an attribute-based approach to discern discrete pottery assemblages; and (b) applying initial OSL dates to facilitate the reliable dating of this site for the first time. Jebel Moya is re-interpreted as a burial complex situated on the southern periphery of the late Meroitic state, and its potential to serve as a chronological and cultural reference point for future studies in south-central and southern Sudan is outlined. PMID:25400300

  9. Collaborative evaluation and market research converge: an innovative model agricultural development program evaluation in Southern Sudan.

    PubMed

    O'Sullivan, John M; O'Sullivan, Rita

    2012-11-01

    In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A partnership of local officials, agricultural development staff, and students worked with the outside team to craft a survey of agricultural traders working between northern Uganda and Southern Sudan the steps approach of a collaborative model. The goal was to create a market directory of use to producers, government officials and others interested in stimulating agricultural trade. The directory of agricultural producers and distributors served as an agricultural development and promotion tool as did the collaborative process itself. PMID:22309968

  10. Jebel Moya (Sudan): new dates from a mortuary complex at the southern Meroitic frontier

    PubMed Central

    Brass, Michael; Schwenniger, Jean-Luc

    2013-01-01

    This paper proposes a new chronology for the burial complex at Jebel Moya, south-central Sudan. It reassesses the body of evidence from Sir Henry Wellcome's original 1911–1914 excavations in order to place the site within a firm chronological framework by: (a) applying an attribute-based approach to discern discrete pottery assemblages; and (b) applying initial OSL dates to facilitate the reliable dating of this site for the first time. Jebel Moya is re-interpreted as a burial complex situated on the southern periphery of the late Meroitic state, and its potential to serve as a chronological and cultural reference point for future studies in south-central and southern Sudan is outlined. PMID:25400300

  11. Jebel Moya (Sudan): new dates from a mortuary complex at the southern Meroitic frontier.

    PubMed

    Brass, Michael; Schwenniger, Jean-Luc

    2013-12-01

    This paper proposes a new chronology for the burial complex at Jebel Moya, south-central Sudan. It reassesses the body of evidence from Sir Henry Wellcome's original 1911-1914 excavations in order to place the site within a firm chronological framework by: (a) applying an attribute-based approach to discern discrete pottery assemblages; and (b) applying initial OSL dates to facilitate the reliable dating of this site for the first time. Jebel Moya is re-interpreted as a burial complex situated on the southern periphery of the late Meroitic state, and its potential to serve as a chronological and cultural reference point for future studies in south-central and southern Sudan is outlined.

  12. Guinea worm disease in Ayod, Upper Nile Province, southern Sudan: a cross-sectional study.

    PubMed

    Guthmann, J P; Mercer, A J; Gandubert, C; Morin, F

    1996-02-01

    Upper Nile Province is one of the four main endemic areas for Guinea worm disease in the Sudan. In December 1994, a survey was conducted in the village of Ayod where the disease is endemic, to investigate morbidity and local knowledge of transmission and prevention. Interviews were conducted in households selected by standard cluster sampling procedures and of the 759 people examined, 156 (20.6%) had Guinea worm lesions. Adjusted odds ratios were used to estimate the relative risk for people with different personal or household characteristics in a multivariate analysis. After controlling for the possible confounding effects of other study variables, having a filter in the household, gender, and lack of knowledge about transmission and about prevention, were not associated with lesions. Only two variables were significantly associated with Guinea worm disease: getting water from a source other than a well increased the risk by a factor of 2.3, and being aged 5 years or more increased the risk by a factor of 31.1. This study demonstrates the clear association between the source of water for drinking and Guinea worm disease found elsewhere. We suggest the provision of reliable sources of pure drinking water and health education are the most suitable long-term preventive measures. The Sudan now represents the greatest challenge to the goal of global eradication of Guinea worm disease, following the reduction in cases in Nigeria. The continuing civil war and insecurity in southern Sudan hinder the implementation of an effective water programme and other control measures, but the potential benefits through reduced incapacity and improved agricultural productivity are considerable.

  13. The epidemiology of trachoma in Eastern Equatoria and Upper Nile States, southern Sudan.

    PubMed Central

    Ngondi, Jeremiah; Onsarigo, Alice; Adamu, Liknaw; Matende, Ibrahim; Baba, Samson; Reacher, Mark; Emerson, Paul; Zingeser, James

    2005-01-01

    OBJECTIVE: Limited surveys and anecdotal data indicate that trachoma is endemic in the states of Eastern Equatoria and Upper Nile in southern Sudan. However, its magnitude and geographical distribution are largely unknown. We conducted surveys to ascertain the prevalence and geographical distribution of trachoma, and to identify targets for control interventions. METHODS: Population-based cross-sectional surveys were conducted in nine sites in southern Sudan between September 2001 and June 2004. Two-stage random cluster sampling with probability proportional to size was used to select the sample. Trachoma grading was done using the WHO simplified grading system. FINDINGS: A total of 17 016 persons were examined, a response rate of 86.1% of the enumerated population. Prevalence of signs of active trachoma in children aged 1-9 years was: TF=53.7% (95% confidence interval (CI)=52.1-55.3); TI=42.7% (95% CI=41.2-44.2); TF and/or TI=64.1% (95% CI=62.5-65.5). Prevalence of trichiasis (TT) in children aged less than 15 years was 1.2% (95% CI=0.9-1.4), while TT prevalence in persons aged 15 years and above was 9.2% (95% CI=8.6-9.9). Women were more likely to have trichiasis compared to men (odds ratio (OR)=1.57; 95% CI=1.34-1.84). Tentative extrapolation to the states of Eastern Equatoria and Upper Nile estimates that there is a backlog of 178,250 (lower and upper bounds=156,027-205,995) persons requiring surgery and the entire population, estimated to be over 3.9 million, is in need of the SAFE strategy to control blinding trachoma. CONCLUSION: Trachoma is a public health problem in all nine of the study sites surveyed. The unusually high prevalence of active trachoma and TT in children points to the severity of the problem. There is urgent need to implement trachoma control interventions in trachoma endemic regions of southern Sudan. PMID:16462982

  14. Health implications of war in Uganda and Sudan.

    PubMed

    Dodge, C P

    1990-01-01

    Civil war disrupted agriculture and trade in Uganda and Sudan. This reduced tax revenues and drained scarce resources away from health budgets to finance increased military expenditures. Hundreds and thousands of people were driven from their homes either as internally displaced people or as refugees. Normal health service delivery systems were broken down forcing doctors, nurses and other health professionals into towns, cities or neighbouring countries in search of peace and employment. Scores of hospitals, health centres and dispensaries were abandoned, destroyed or looted, rendering even the limited physical facilities useless. Preventive public health services such as immunization and provision of potable drinking water were discontinued leaving huge populations susceptible to controllable infectious diseases and epidemics. PMID:2122523

  15. Lessons learned from translators and interpreters from the Dinka tribe of southern Sudan.

    PubMed

    Baird, Martha B

    2011-04-01

    This article discusses the methodological challenges associated with working with translators and interpreters from the Dinka tribe of southern Sudan during an ethnographic study with refugee Dinka women who were resettled with their children in the United States. Navigating the cultural differences between the researcher, the translator, and the interpreters provided a deeper understanding about the culture of the study population. The lessons learned included the importance of cultural congruence between the interpreters and participants; the education, training, and experience of the interpreters; and the difficulties encountered in preparing interpreters according to university institutional review board requirements. Cultural differences such as time perception and communication and literacy styles were negotiated throughout each phase of the study. The most valuable lesson learned from this experience was the importance of the relationship between the researcher, the translator, and the interpreters as well as between the interpreters and participants to achieve credibility and trustworthiness of the study results. PMID:21317404

  16. The mythology of the killer deciduous canine tooth in southern Sudan.

    PubMed

    Baba, S P; Kay, E J

    1989-01-01

    In Southern Sudan it is a commonly held belief that the unerupted deciduous canine tooth is injurious to the health of infants and that it causes diarrheal diseases. The teeth are therefore often removed by native extractors in an attempt to alleviate the symptoms of these dangerous diseases. This study examined the prevalence of this practice among babies presenting at a hospital, and examined the health status of the infants involved. The 90 infants in the study had all had at least one deciduous tooth removed, and the great majority were suffering from dehydration, caused by various abdominal diseases. It is clear that an educational campaign aimed at reducing the prevalence of this practice is required.

  17. Studies on the livestock of Southern Darfur, Sudan. IV. Production traits in goats.

    PubMed

    Wilson, R T

    1976-11-01

    The results of a 15 months' intensive study on seven flocks of indigenous goats in the Southern Darfur region of the Sudan are discussed in this paper. Birth rates in the region approached 2-1 kids per doe per year. A high total offtake of 28 per cent and a weighted average death rate of about 16-5 per cent were insufficient to offset this high birth rate and flock numbers are increased. Mortality in kids was unrelated to number of births. Weighted average rate of gain for all surviving kids was 87 g per day to 3 months and 67 g per day to 6 months of age. The growth rates of twin and single were similar, but triplet kids grew at a slower rate. For each kilogramme liveweight of breeding females, goats produced 1-5 and 8 times the weight of meat produced by sheep and cattle respectively under the same management and environmental conditions.

  18. Prevalence of livestock diseases and their impact on livelihoods in Central Equatoria State, Southern Sudan.

    PubMed

    Malak, A K; Mpoke, L; Banak, J; Muriuki, S; Skilton, R A; Odongo, D; Sunter, J; Kiara, H

    2012-05-01

    A participatory epidemiological (PE) study was conducted in Kajo Keji and Yei Counties, Central Equatoria State, southern Sudan to assess the impact of livestock diseases on livelihoods. A serological survey of tick-borne diseases was conducted to supplement the PE study. PE data collection tools consisted primarily of focus group interviews and key informant interviews supplemented by observation. Information was collected on the social context, history and species of livestock kept. Constraints in livestock keeping were explored through description and probing. Proportional piling on the importance of different diseases and relative incidence scoring were also conducted. 243 sera were collected from cattle and tested for antibodies to Anaplasma marginale, Babesia bigemina, B. bovis, Theileria mutans and T. parva by ELISA. Additionally, 173 blood samples were collected for a PCR assay of T. parva. Livestock diseases were ranked as the most important constraint to livestock keeping. While East Coast fever was ranked as the most important disease in Kajo Keji, diarrhoea in small ruminants was reported as the most important disease in Yei. Serological analyses of the sera indicated that A. marginale, B. bigemina, T. mutans and T. parva were most prevalent. Prevalence of B. bovis was found to be low (4.0% and 7.4% in Kajo Keji and Yei, respectively). 35% of the samples screened with the T. parva p104 gene nested PCR assay were positive. The study concludes that while ECF is the most important disease in Kajo Keji, it was not the case in Yei. Additional epidemiological studies are proposed before control strategies are recommended. PMID:22244519

  19. Integrated Surveys of Neglected Tropical Diseases in Southern Sudan: How Much Do They Cost and Can They Be Refined?

    PubMed Central

    Kolaczinski, Jan H.; Hanson, Kara; Robinson, Emily; Picon, Diana; Sabasio, Anthony; Mpakateni, Martin; Lado, Mounir; Moore, Stephen; Petty, Nora; Brooker, Simon

    2010-01-01

    Background Increasing emphasis on integrated control of neglected tropical diseases (NTDs) requires identification of co-endemic areas. Integrated surveys for lymphatic filariasis (LF), schistosomiasis and soil-transmitted helminth (STH) infection have been recommended for this purpose. Integrated survey designs inevitably involve balancing the costs of surveys against accuracy of classifying areas for treatment, so-called implementation units (IUs). This requires an understanding of the main cost drivers and of how operating procedures may affect both cost and accuracy of surveys. Here we report a detailed cost analysis of the first round of integrated NTD surveys in Southern Sudan. Methods and Findings Financial and economic costs were estimated from financial expenditure records and interviews with survey staff using an ingredients approach. The main outcome was cost per IU surveyed. Uncertain variables were subjected to univariate sensitivity analysis and the effects of modifying standard operating procedures were explored. The average economic cost per IU surveyed was USD 40,206 or USD 9,573, depending on the size of the IU. The major cost drivers were two key categories of recurrent costs: i) survey consumables, and ii) personnel. Conclusion The cost of integrated surveys in Southern Sudan could be reduced by surveying larger administrative areas for LF. If this approach was taken, the estimated economic cost of completing LF, schistosomiasis and STH mapping in Southern Sudan would amount to USD 1.6 million. The methodological detail and costing template provided here could be used to generate cost estimates in other settings and readily compare these to the present study, and may help budget for integrated and single NTDs surveys elsewhere. PMID:20644619

  20. They Own This: Mother Tongue Instruction for Indigenous Kuku Children in Southern Sudan

    ERIC Educational Resources Information Center

    Laguarda, Ana Isabel; Woodward, Walter Pierce

    2013-01-01

    This article details a pilot program of mother tongue instruction in five primary schools for classes one through three, in Kajokeji County, Central Equatoria State, South Sudan. The program was launched by teachers and volunteers with the support of the Jesuit Refugee Service, an international non-governmental organization. The research examines…

  1. Post-conflict mental health needs: a cross-sectional survey of trauma, depression and associated factors in Juba, Southern Sudan

    PubMed Central

    Roberts, Bayard; Damundu, Eliaba Yona; Lomoro, Olivia; Sondorp, Egbert

    2009-01-01

    Background The signing of the Comprehensive Peace Agreement in January 2005 marked the end of the civil conflict in Sudan lasting over 20 years. The conflict was characterised by widespread violence and large-scale forced migration. Mental health is recognised as a key public health issue for conflict-affected populations. Studies revealed high levels of post-traumatic stress disorder (PTSD) amongst populations from Southern Sudan during the conflict. However, no studies have been conducted on mental health in post-war Southern Sudan. The objective of this study was to measure PTSD and depression in the population in the town of Juba in Southern Sudan; and to investigate the association ofdemographic, displacement, and past and recent trauma exposure variables, on the outcomes of PTSD and depression. Methods A cross-sectional, random cluster survey with a sample of 1242 adults (aged over 18 years) was conducted in November 2007 in the town of Juba, the capital of Southern Sudan. Levels of exposure to traumatic events and PTSD were measured using the Harvard Trauma Questionnaire (original version), and levels of depression measured using the Hopkins Symptom Checklist-25. Multivariate logistic regression was used to analyse the association ofdemographic, displacement and trauma exposure variables on the outcomes of PTSD and depression. Multivariate logistic regression was also conducted to investigate which demographic and displacement variables were associated with exposure to traumatic events. Results Over one third (36%) of respondents met symptom criteria for PTSD and half (50%) of respondents met symptom criteria for depression. The multivariate logistic regression analysis showed strong associations of gender, marital status, forced displacement, and trauma exposure with outcomes of PTSD and depression. Men, IDPs, and refugees and persons displaced more than once were all significantly more likely to have experienced eight or more traumatic events. Conclusion

  2. Studies on the livestock of Southern Darfur, Sudan. II. Production traits in cattle.

    PubMed

    Wilson, R T; Clarke, S E

    1976-02-01

    The results of an intensive 12 months study of a number of herds in the migratory and sedentary sectors of the livestock economy of Southern Darfur are recorded. In almost every production parameter the performance of the former is superior to that of the latter but, overall, production appears to be static or declining. During 1973 the cattle population of the area is estimated to have declined 7 per cent. Meat production per kilogramme of breeding female was calculated to be 0-057 kg in the migratory sector but only 0-023 kg in the sedentary sector. Calculated calving rates are significantly higher at 65 per cent in the migratory sector than the 40 per cent of the sedentary sector. Deaths in the former sector were only 15 per cent compared with the 35 per cent of the latter. It is concluded that total settlement of the migratory sector is not the answer to the current problem of the livestock sector of Southern Darfur.

  3. Studies on the livestock of Southern Darfur, Sudan, VII. Production of poultry under simulated traditional conditions.

    PubMed

    Wilson, R T

    1979-08-01

    Observations were made on egg production, egg hatchability and fertility, liveweight and growth characteristics of domestic fowls, Muscovy ducks and pigeons kept under simulated traditional conditions in Southern Darfur. Fowl and ducks produced about 50 eggs a year in 4 1/2 clutches spaced at 80 day intervals and pigeons 17 in 8 1/2 clutches at 43 day intervals. First eggs were laid at about 240 days by the fowls, 213 days by ducks and 132 days by pigeons. The annual weight of eggs produced was 2,013 3,596 and 286 g for fowl, ducks and pigeons respectively, being 1.53, 2.33 and 0.88 times the mean adult female body weight for each species. Fertility and hatchability of eggs were higher in fowls than ducks which were in turn higher than in pigeons. Early growth in pigeons was very rapid. Muscovies achieved mature body weights at about 20 weeks while mature weights in fowls were achieved much later in males than in females.

  4. 75 FR 75865 - Presidential Determination on Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... enables the United Nations to facilitate the referendum in Southern Sudan pursuant to the Comprehensive... Sudan Memorandum for the Secretary of State President of the Export-Import Bank of the United States By the authority vested in me as President by the Constitution and the laws of the United States...

  5. The Birth of a New Nation: The Republic of South Sudan

    ERIC Educational Resources Information Center

    Totten, Samuel

    2011-01-01

    In early July, the country of Sudan, wracked by civil war since the 1980s, officially split into two separate nations, Sudan and South Sudan. Six months earlier, over a seven-day period, the people in southern Sudan had voted in a national referendum on whether to secede from the North. The voters had two choices: "Separation" or "Unity." For the…

  6. A sensitivity study on the role of the swamps of southern Sudan in the summer climate of North Africa using a regional climate model

    NASA Astrophysics Data System (ADS)

    Zaroug, Modathir A. H.; Sylla, M. B.; Giorgi, F.; Eltahir, Elfatih A. B.; Aggarwal, Pradeep K.

    2013-07-01

    We used the regional climate model RegCM3 to investigate the role of the swamps of southern Sudan in affecting the climate of the surrounding region. Towards this end, we first assessed the performance of a high resolution version of the model over northern Africa. RegCM3 shows a good skill in simulating the climatology of rainfall and temperature patterns as well as the related circulation features during the summer season, outperforming previous coarser resolution applications of the model over this region. Sensitivity experiments reveal that, relative to bare soil conditions, the swamps act to locally modify the surface energy budget primarily through an increase of surface latent heat flux. Existence of the swamps leads to lower ground temperature (up to 2 °C), a larger north-south temperature gradient, and increased local rainfall (up to 40 %). Of particular importance is the impact on rainfall in the surrounding regions. The swamps have almost no impact on the rainfall over the source region of the Nile in Ethiopia or in the Sahel region; however, they favor wetter conditions over central Sudan (up to 15 %) in comparison to the bare desert soil conditions.

  7. The influence of demographic characteristics, living conditions, and trauma exposure on the overall health of a conflict-affected population in Southern Sudan

    PubMed Central

    2010-01-01

    Background There remains limited evidence on how armed conflict affects overall physical and mental well-being rather than specific physical or mental health conditions. The aim of this study was to investigate the influence of demographic characteristics, living conditions, and violent and traumatic events on general physical and mental health in Southern Sudan which is emerging from 20 years of armed conflict. Methods A cross-sectional survey of 1228 adults was conducted in November 2007 in the town of Juba, the capital of Southern Sudan. Multivariate linear regression analysis was used to investigate the associations and relative influence of variables in three models of demographic characteristics, living conditions, and trauma exposure, on general physical and mental health status. These models were run separately and also as a combined model. Data quality and the internal consistency of the health status instrument (SF-8) were assessed. Results The variables in the multivariate analysis (combined model) with negative coefficients of association with general physical health and mental health (i.e. worse health), respectively, were being female (coef. -2.47; -2.63), higher age (coef.-0.16; -0.17), absence of soap in the household (physical health coef. -2.24), and experiencing within the past 12 months a lack of food and/or water (coef. -1.46; -2.27) and lack of medical care (coef.-3.51; -3.17). A number of trauma variables and cumulative exposure to trauma showed an association with physical and mental health (see main text for data). There was limited variance in results when each of the three models were run separately and when they were combined, suggesting the pervasive influence of these variables. The SF-8 showed good data quality and internal consistency. Conclusions This study provides evidence on the pervasive influence of demographic characteristics, living conditions, and violent and traumatic events on the general physical and mental health of a

  8. Flood pulsing in the Sudd wetland: analysis of seasonal variations in 2 inundation and evapotranspiration in Southern Sudan

    USGS Publications Warehouse

    Senay, Gabriel B.; Rebelo, L-M.; McCartney, M.P.

    2012-01-01

    Located on the Bahr el Jebel in South Sudan, the Sudd is one of the largest floodplain wetlands in the world. Seasonal inundation drives the hydrologic, geomorphological, and ecological processes, and the annual flood pulse is essential to the functioning of the Sudd. Despite the importance of the flood pulse, various hydrological interventions are planned upstream of the Sudd to increase economic benefits and food security. These will not be without consequences, in particular for wetlands where the biological productivity, biodiversity, and human livelihoods are dependent on the flood pulse and both the costs and benefits need to be carefully evaluated. Many African countries still lack regional baseline information on the temporal extent, distribution, and characteristics of wetlands, making it hard to assess the consequences of development interventions. Because of political instability in Sudan and the inaccessible nature of the Sudd, recent measurements of flooding and seasonal dynamics are inadequate. Analyses of multitemporal and multisensor remote sensing datasets are presented in this paper, in order to investigate and characterize flood pulsing within the Sudd wetland over a 12-month period. Wetland area has been mapped along with dominant components of open water and flooded vegetation at five time periods over a single year. The total area of flooding (both rain and river fed) over the 12 months was 41 334 km2, with 9176 km2 of this constituting the permanent wetland. Mean annual total evaporation is shown to be higher and with narrower distribution of values from areas of open water (1718 mm) than from flooded vegetation (1641 mm). Although the exact figures require validation against ground-based measurements, the results highlight the relative differences in inundation patterns and evaporation across the Sudd.

  9. Clinical symptoms, treatment and outcome of highlands malaria in Eldoret (2420 m a.s.l.) and comparison to malaria in hyper-immune population in endemic region of Southern Sudan.

    PubMed

    Benca, J; Dubai, A; Sladeckova, V

    2007-11-01

    Malaria should not be present in altitudes more than 1,800 m a.s.l. However due to global warming, highlands malaria (HM) occurs up to 2,000 m. The purpose of this study is comparison of clinical picture and prognosis of HM and compare it to malaria in endemic region of southern Sudan (endemic malaria - EM) among hyper-immune population.

  10. Spectral P-wave magnitudes, magnitude spectra and other source parameters for the 1990 southern Sudan and the 2005 Lake Tanganyika earthquakes

    NASA Astrophysics Data System (ADS)

    Moussa, Hesham Hussein Mohamed

    2008-10-01

    Teleseismic Broadband seismograms of P-waves from the May 1990 southern Sudan and the December, 2005 Lake Tanganyika earthquakes; the western branch of the East African Rift System at different azimuths have been investigated on the basis of magnitude spectra. The two earthquakes are the largest shocks in the East African Rift System and its extension in southern Sudan. Focal mechanism solutions along with geological evidences suggest that the first event represents a complex style of the deformation at the intersection of the northern branch of the western branch of the East African Rift and Aswa Shear Zone while the second one represents the current tensional stress on the East African Rift. The maximum average spectral magnitude for the first event is determined to be 6.79 at 4 s period compared to 6.33 at 4 s period for the second event. The other source parameters for the two earthquakes were also estimated. The first event had a seismic moment over fourth that of the second one. The two events are radiated from patches of faults having radii of 13.05 and 7.85 km, respectively. The average displacement and stress drop are estimated to be 0.56 m and 1.65 MPa for the first event and 0.43 m and 2.20 MPa for the second one. The source parameters that describe inhomogeneity of the fault are also determined from the magnitude spectra. These additional parameters are complexity, asperity radius, displacements across the asperity and ambient stress drop. Both events produce moderate rupture complexity. Compared to the second event, the first event is characterized by relatively higher complexity, a low average stress drop and a high ambient stress. A reasonable explanation for the variations in these parameters may suggest variation in the strength of the seismogenic fault which provides the relations between the different source parameters. The values of stress drops and the ambient stresses estimated for both events indicate that these earthquakes are of interplate

  11. Al Jazirah, Sudan

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Al Jazirah (also Gezira) is one of the 26 states of Sudan. The state lies between the Blue Nile and the White Nile in the east-central region of the country. It is a well populated area suitable for agriculture. The area was at the southern end of Nubia and little is known about its ancient history and only limited archaeological work has been conducted in this area. The region has benefited from the Gezira Scheme, a program to foster cotton farming begun in 1925. At that time the Sennar Dam and numerous irrigation canals were built. Al Jazirah became the Sudan's major agricultural region with more than 2.5 million acres (10,000 km) under cultivation. The initial development project was semi-private, but the government nationalized it in 1950. Cotton production increased in the 1970s but by the 1990s increased wheat production has supplanted a third of the land formerly seeded with cotton.

    The image was acquired December 25, 2006, covers an area of 56 x 36.4 km, and is located near 14.5 degrees north latitude, 33.1 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  12. A climate trend analysis of Sudan

    USGS Publications Warehouse

    Funk, Christopher C.; Eilerts, Gary; Verdin, Jim; Rowland, Jim; Marshall, Michael

    2011-01-01

    Summer rains in western and southern Sudan have declined by 10-20 percent since the mid-1970s. Observed warming of more than 1 degree Celsius is equivalent to another 10-20 percent reduction in rainfall for crops. The warming and drying have impacted southern Darfur and areas around Juba. Rainfall declines west of Juba threaten southern Sudan's future food production prospects. In many cases, areas with changing climate are coincident with zones of substantial conflict, suggesting some degree of association; however, the contribution of climate change to these conflicts is not currently understood. Rapid population growth and the expansion of farming and pastoralism under a more variable climate regime could dramatically increase the number of at-risk people in Sudan over the next 20 years.

  13. Measuring turbidity, and indicator to evaluate drinkability of waters in Southern countries? Approaches from Burkina Faso, Sudan and Argentina case studies

    NASA Astrophysics Data System (ADS)

    Lavie, Emilie; Robert, Elodie

    2013-04-01

    The relationship between proportion of suspended solids, dissolved oxygen and bacteriology has long been proven (Brock, 1966; Lechevallier et al., 1985; Bustina and Levallois, 2003; Chang and Liao, 2012), bacteria need coarse elements to hang on and develop. However, water bacteriology analyses are difficult to implement in southern countries. They are expensive and require sterile equipment, transport in cold conditions and a nearby laboratory, which remains difficult in remote areas under these hot latitudes. Yet, simple measurement devices allow to know in a few minutes the water turbidity. Is turbidity an efficient tool to evaluate the drinkability of water when no bacteriological analyses are possible? The results proposed here are taken from three different studies whose purposes were to measure different physical, chemical and bacteriological parameters of water used for human and/or animal consumption. One of the finalities was to propose a method, at lower cost, to evaluate the drinkability of water for consumption. Four case studies were chosen: the basin of the Doubegue River in Burkina Faso is a rural area of a developing country, where drinking water is taken from the alluvial aquifer close to the surface. Furthermore, the laundry is washed and the children play in running streams. Major expansion of the cultivated lands since 1980s has brought important soils losses, thus a chronicle contamination of surface water with suspended solids (Robert, 2012). The Mendoza and Tunuyán Rivers Basins in Argentina, an emerging country, have snow-glaciar regimes with naturally turbid waters. They supply drinking water to two towns, Mendoza and Tunuyán cities, respectively 1 million and 40,000 inhabitants. However, these two streams -whose watersheds are common- do not present the same managements: the Mendoza River has been equipped with large hydraulic infrastructures, moving the turbid waters into clear and erosive ones (Lavie, 2009), while the Tunuyán River

  14. Nodding syndrome - South Sudan, 2011.

    PubMed

    2012-01-27

    In November 2010, the Ministry of Health of the proposed nation of South Sudan requested CDC assistance in investigating a recent increase and geographic clustering of an illness resulting in head nodding and seizures. The outbreak was suspected to be nodding syndrome, an unexplained neurologic condition characterized by episodes of repetitive dropping forward of the head, often accompanied by other seizure-like activity, such as convulsions or staring spells. The condition predominantly affects children aged 5-15 years and has been reported in South Sudan from the states of Western and Central Equatoria and in Northern Uganda and southern Tanzania. Because of visa and security concerns, CDC investigators did not travel to South Sudan until May 2011. On arrival, a case-control study was conducted that included collecting exposure information and biologic specimens to assess the association of nodding syndrome with suspected risk factors. A total of 38 matched case-control pairs were enrolled from two different communities: Maridi and Witto. Overall, current infection with Onchocerca volvulus diagnosed by skin snip was more prevalent among the 38 case-patients (76.3%) than the controls (47.4%) (matched odds ratio [mOR] = 3.2). This difference was driven by the 25 pairs in Maridi (88.0% among case-patients, 44.0% among controls, mOR=9.3); among the 13 pairs in Witto, no significant association with onchocerciasis (known as river blindness) was observed. Although onchocerciasis was more prevalent among case-patients, whether infection preceded or followed nodding syndrome onset was unknown. Priorities for nodding syndrome investigations include improving surveillance to monitor the number of cases and their geographic distribution and continued work to determine the etiology of the syndrome. PMID:22278159

  15. Seismotectonic implications of sand blows in the southern Mississippi Embayment

    USGS Publications Warehouse

    Cox, R.T.; Hill, A.A.; Larsen, D.; Holzer, T.; Forman, S.L.; Noce, T.; Gardner, C.; Morat, J.

    2007-01-01

    We explore seismically-induced sand blows from the southern Mississippi Embayment and their implications in resolving the question of near or distal epicentral source region. This was accomplished using aerial photography, field excavations, and cone penetration tests. Our analysis shows that three sand blow fields exhibit a distinct chronology of strong ground motion for the southern embayment: (1) The Ashley County, Arkansas sand blow field, near the Arkansas/Louisiana state border, experienced four Holocene sand venting episodes; (2) to the north, the Desha County field experienced at least three episodes of liquefaction; and (3) the Lincoln-Jefferson Counties field experienced at least one episode. Cone penetration tests (CPT) conducted in and between the sand blow fields suggest that the fields may not be distal liquefaction associated with New Madrid seismic zone earthquakes but rather are likely associated with strong earthquakes on local faults. This conclusion is consistent with the differences in timing of the southern embayment sand venting episodes and those in the New Madrid seismic zone. These results suggest that active tectonism and strong seismicity in intraplate North America may not be localized at isolated weak spots, but rather widespread on fault systems that are favorably oriented for slip in the contemporary stress field. ?? 2006 Elsevier B.V. All rights reserved.

  16. Demanding Divestment from Sudan

    ERIC Educational Resources Information Center

    Asquith, Christina

    2006-01-01

    Bowing to student demands to "stop supporting genocide," the University of California regents voted earlier this year to divest millions of dollars from companies working in the war-torn African nation of Sudan, the first major public university in the nation to take such action. Since student protests on the subject began at Harvard University in…

  17. UNICEF and the Sudan.

    ERIC Educational Resources Information Center

    United Nations Children's Fund, Nairobi (Kenya). Eastern Africa Regional Office.

    Coupled with poor infrastructure, vast distances, and harsh climatic conditions, the enormous physical obstacles in the Sudan (Africa's largest country) have combined to produce extremely serious problems for Sudanese children, who will soon constitute half of the 17 million people there. This booklet describes continuing projects implemented by…

  18. The Politics of Writing Tribal Identities in the Sudan: The Case of the Colonial Nuba Policy

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf Kamal

    2010-01-01

    Linguistics is implicated in the colonial project of the invention of "self-contained" "racial" and "tribal units" in the Sudan. This paper has two objectives. First, to historicise the notions of "language" in the postcolonial discourse of language planning in the Sudan by reviewing one of the significant colonial policies: the colonial Nuba…

  19. Vitamin A deficiency in the Sudan: a call for a surveillance system.

    PubMed

    el Bushra, H E

    1992-05-01

    This short review summarizes all the published and unpublished reports on vitamin A deficiency in the Sudan in the last four decades. Different local terms used by people to indicate vitamin A deficiency were enlisted. There is evidence that vitamin A deficiency is a public health problem in eastern Sudan and among communities from western and southern Sudan living around Greater Khartoum, who were displaced from their homelands because of drought, famine conditions and civil unrest. There are reports indicative of vitamin A deficiency problem in the central and the far western provinces. There were no reports from the northern provinces. The need for a surveillance system was discussed.

  20. Real lives 2: Sudan.

    PubMed

    Werner, L

    1994-01-01

    The great Sudan famine of the mid-1980s caused social dislocation and political chaos which ultimately toppled the long-time military leader. Hundreds of thousands of farmers and pastoralists were displaced, driven from the western provinces into urban feeding stations and squatter settlements. Camps at Abu Zayd and Mwellih near Umdurman filled with over 100,000 refugees in a matter of months, while camps at Ed Debba on the Nile River's Nubian reach filled with tribesmen desperate to sell sheep and goats weakening daily. The aftershock of the environmental disaster continues to reverberate at all levels of state and society. The author describes the story of one nomadic camel breeder and his family forced to liquidate their holdings at bargain prices and seek refuge in the capital.

  1. Atmospheric Teleconnections of Northern Hemisphere cooling to the Southern Hemisphere midlatitudes, and implications for Southern Ocean ventilation

    NASA Astrophysics Data System (ADS)

    Chiang, John; Lee, Shih-Yu; Matsumoto, Katsumi; Tokos, Kathy

    2010-05-01

    Recent marine proxy studies, most notably by Anderson et al. (2009), show intensification of wind-driven upwelling in the Southern Ocean during Heinrich events, and suggesting the possibility of robust atmospheric teleconnections from the Northern Hemisphere affecting the Southern Hemisphere midlatitude westerlies. We explore the latter hypothesis using simulations of an AGCM coupled to a reduced-gravity ocean, and with reference to current thinking regarding extratropical-tropical atmospheric dynamical linkages. When we simulate a Heinrich-like event in our model (by cooling the North Atlantic), we find a significant strengthening of the southern midlatitude westerlies, in particular during the austral winter (JJA), and in the South Pacific. The other pronounced climate change is a marked southward shift of the tropical rainbelt, indicating alteration of the Hadley circulation. Our analysis indicates that the teleconnection can be broken into two parts: first, the northern hemisphere cooling shifting the ITCZ southwards with a pronounced effect on the Hadley circulation (Lindzen and Hou 1988), and then the altered Hadley circulation in turn affecting the southern midlatitude westerlies through the former's control of the southern subtropical westerlies and subsequent effect on the eddy-driven midlatitude westerlies (Lee and Kim, 2003). The seasonal (JJA) and regional (South Pacific) preference of the teleconnection's effects can be explained in terms of the peculiarities of the regional atmospheric dynamics. As an aside, we also find that the growth or decay of the Laurentide ice sheet can also generate this type of north-south teleconnection, although the dynamics are somewhat different. With regards to possible implications for southern ocean ventilation and atmospheric CO2: we applied the wind changes we obtained in our AGCM 'Heinrich' simulation to a global biogeochemical model (the Minnesota Earth System Model for Ocean biogeochemistry), and found a ~20ppm

  2. Seismic Hazard Implication of the Seismotectonics of southern Africa

    NASA Astrophysics Data System (ADS)

    Midzi, Vunganai; Mulabisana, Thifelimbilu; Manzunzu, Brassnavy

    2014-05-01

    The work presented in this report / presentation was prepared as part of the requirements for the SIDA/IGCP Project 601 titled "Seismotectonics and Seismic Hazards in Africa" as well as part of the seismic source characterisation of the GEM-Africa Seismic hazard study. An effort was made to compile information necessary to prepare a seismotectonic map of Africa which can then be used in carrying out a seismic hazard assessment of the continent or locations within the continent. Information on major faults, fault plane solutions, geophysical data as well as stress data has so far been collected and included in a database for the southern Africa region. Reports published by several experts contributed much to the collected information. The seismicity data used are part of the earthquake catalogue being prepared for the GEM-Africa project, which includes historical and instrumental records as collected from various sources. An effort has been made to characterise the identified major faults and through further analysis investigate their possible impact on the seismic hazard of southern Africa.

  3. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    PubMed Central

    Ageep, Tellal B; Cox, Jonathan; Hassan, M'oawia M; Knols, Bart GJ; Benedict, Mark Q; Malcolm, Colin A; Babiker, Ahmed; El Sayed, Badria B

    2009-01-01

    Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe) adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS), Geographical Information Systems (GIS) and the Global Positioning System (GPS) was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6%) contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not evident in vector

  4. Petrogenesis and tectonic implications of the Yadong leucogranites, southern Himalaya

    NASA Astrophysics Data System (ADS)

    Gou, Zhengbin; Zhang, Zeming; Dong, Xin; Xiang, Hua; Ding, Huixia; Tian, Zuolin; Lei, Hengcong

    2016-07-01

    The leucogranites in the Higher Himalayan Sequence (HHS) provide a probe to elucidate the crustal melting of continental collisional orogen. An integrated geochemical and geochronological study of the Yadong leucogranites, southern Himalaya, shows that these rocks have relatively high SiO2 contents of 69.77 to 75.32 wt.% and alumina saturation index (A/CNK) of 1.09-1.40, typical of peraluminous granites. They show moderately fractionated REE patterns with negative Eu anomalies, and are characterized by enriched LILE (Rb and Cs) and depleted HFSE (Zr, Hf, Nb and Ta). LA-ICP-MS U-Pb zircon dating of ten samples yields crystallization ages ranging from 21.0 to 11.7 Ma. The zircons have variable εHf(t) values of - 26.3 to - 3.5 and corresponding Hf two-stage model ages of 2.77-1.33 Ga. The present study reveals that the muscovite-biotite leucogranites (2ML) have higher TiO2, MgO, CaO, Sr, Ba and Zr contents, lower Rb/Sr ratios than the tourmaline-muscovite leucogranites (TML). Zircon and monazite saturation thermometry results show that the melt temperatures (681-784 °C) of the 2ML are 20-80 °C higher than those (663-705 °C) of the TML. Combining with previous results, we propose that the TML were derived from the muscovite-dehydration melting, whereas the 2ML dominantly resulted from the biotite-dehydration melting during the prograde metamorphism of the pelitic and felsic granulites of the HHS. Therefore, the Himalayan leucogranites were probably formed during the subduction of the Indian crust following the India and Asia collision.

  5. Agricultural fields, Khartoum, Sudan, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) is very distinctive in both size and shape. The region contains thousands of these rectangular fields bounded by canals which carry water from both the White and Blue Nile Rivers. A crop rotation system is used so that some fields are in cotton, millit, sorghum or fallow to conserve moisture and control weeds and insects. See also STS049-96-003.

  6. Earth Science Education in Sudan

    NASA Astrophysics Data System (ADS)

    Abdullatif, Osman M.; Farwa, Abdalla G.

    1999-05-01

    This paper describes Earth Science Education in Sudan, with particular emphasis on the University of Khartoum. The first geological department in Sudan was founded in 1958 in the University of Khartoum. In the 1980s, six more geological departments have been added in the newer universities. The types of courses offered include Diploma, B.Sc. (General), B.Sc. (Honours), M.Sc. and Ph.D. The Geology programmes are strongly supported by field work training and mapping. Final-year students follow specialised training in one of the following topics: hydrogeology, geophysics, economic geology, sedimentology and engineering geology. A graduation report, written in the final year, represents 30-40% of the total marks. The final assessment and grading are decided with the help of internal and external examiners. Entry into the Geology programmes is based on merit and performance. The number of students who graduate with Honours and become geologists is between 20% to 40% of the initial intake at the beginning of the second year. Employment opportunities are limited and are found mainly in the Government's geological offices, the universities and research centres, and private companies. The Department of Geology at the University of Khartoum has long-standing internal and external links with outside partners. This has been manifested in the training of staff members, the donation of teaching materials and laboratory facilities. The chief problems currently facing Earth Science Education in Sudan are underfunding, poor equipment, laboratory facilities and logistics. Other problems include a shortage of staff, absence of research, lack of supervision and emigration of staff members. Urgent measures are needed to assess and evaluate the status of Earth Science Education in terms of objectives, needs and difficulties encountered. Earth Science Education is expected to contribute significantly to the exploitation of mineral resources and socio-economic development in the Sudan.

  7. Human Resources for Information Development in Sudan.

    ERIC Educational Resources Information Center

    Wesley, Cecile

    1992-01-01

    Describes the state of human resources development in Sudan's information industry. Training problems and the emigration of high level personnel are discussed, guidelines for human resource development are suggested, and national strategies to develop and retain Sudan's human resources are suggested. (EA)

  8. 31 CFR 538.305 - Government of Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Government of Sudan. 538.305 Section... § 538.305 Government of Sudan. The term Government of Sudan includes: (a) The state and the Government... § 538.305: The term Government of Sudan does not include the Government of the Republic of South...

  9. 31 CFR 538.305 - Government of Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Government of Sudan. 538.305 Section... § 538.305 Government of Sudan. The term Government of Sudan includes: (a) The state and the Government... § 538.305: The term Government of Sudan does not include the Government of the Republic of South...

  10. 31 CFR 538.305 - Government of Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Government of Sudan. 538.305 Section... § 538.305 Government of Sudan. The term Government of Sudan includes: (a) The state and the Government... § 538.305: The term Government of Sudan does not include the Government of the Republic of South...

  11. 31 CFR 538.305 - Government of Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Government of Sudan. 538.305 Section... § 538.305 Government of Sudan. (a) The term Government of Sudan includes: (1) The state and the Government of Sudan, as well as any political subdivision, agency, or instrumentality thereof, including...

  12. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan... for the following legal services by U.S. persons to the Government of Sudan or to a person in Sudan... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Provision of certain legal services...

  13. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan... for the following legal services by U.S. persons to the Government of Sudan or to a person in Sudan... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Provision of certain legal services...

  14. Sudan challenges the sand dragon.

    PubMed

    Tinker, J

    1978-01-01

    Formerly productive areas have become wasteland as the desert advances in the Sudan. To understand how desertification is undermining the very survival of the Sahel, one ecosystem is reviewed in detail here: the gum arabic zone of Kordofan. After cotton, gum arabic is Sudan's largest export, worth from $14-26 million in recent years. In this zone the ecologically balanced cycle of gum gardens, fire, grain crops, and fallow is now breaking down; the 1968-1973 drought having in many areas delivered the final blow. Because of a growing population, the cultivation period is extended, and the soil becomes impoverished. Overgrazing in the fallow period, and the lopping of gum trees for firewood is producing a low return on the gum trees. Without this gum to harvest for cash, farmers must repeatedly replant their subsistence crops until the land becomes useless sand. The Sudanese have recognized the problem earlier than most, and a number of imaginative and practicable pilot projects are already in use: 1) waterpoint management; 2) construction of firebreaks; 3) land threatened by shifting dunes has been enclosed by stockproof fence and afforested with local trees; and 4) shelter belts have been planted around town perimeters where old gum tree stumps have started to sprout and the grass is reseeding itself. Out of these pilot projects, and with the advice of the U.N. Environment Program, the U.N. Development Program, and FAO, the Sudanese have developed a modest $26 million desert encroachment control and rehabilitation program (DECARP). PMID:12278008

  15. Identification of two distinct fire regimes in Southern California: implications for economic impact and future change

    NASA Astrophysics Data System (ADS)

    Jin, Yufang; Goulden, Michael L.; Faivre, Nicolas; Veraverbeke, Sander; Sun, Fengpeng; Hall, Alex; Hand, Michael S.; Hook, Simon; Randerson, James T.

    2015-09-01

    The area burned by Southern California wildfires has increased in recent decades, with implications for human health, infrastructure, and ecosystem management. Meteorology and fuel structure are universally recognized controllers of wildfire, but their relative importance, and hence the efficacy of abatement and suppression efforts, remains controversial. Southern California’s wildfires can be partitioned by meteorology: fires typically occur either during Santa Ana winds (SA fires) in October through April, or warm and dry periods in June through September (non-SA fires). Previous work has not quantitatively distinguished between these fire regimes when assessing economic impacts or climate change influence. Here we separate five decades of fire perimeters into those coinciding with and without SA winds. The two fire types contributed almost equally to burned area, yet SA fires were responsible for 80% of cumulative 1990-2009 economic losses (3.1 Billion). The damage disparity was driven by fire characteristics: SA fires spread three times faster, occurred closer to urban areas, and burned into areas with greater housing values. Non-SA fires were comparatively more sensitive to age-dependent fuels, often occurred in higher elevation forests, lasted for extended periods, and accounted for 70% of total suppression costs. An improved distinction of fire type has implications for future projections and management. The area burned in non-SA fires is projected to increase 77% (±43%) by the mid-21st century with warmer and drier summers, and the SA area burned is projected to increase 64% (±76%), underscoring the need to evaluate the allocation and effectiveness of suppression investments.

  16. Serosurvey of prevalence of human immunodeficiency virus amongst high risk groups in Port Sudan, Sudan.

    PubMed

    Burans, J P; McCarthy, M; el Tayeb, S M; el Tigani, A; George, J; Abu-Elyazeed, R; Woody, J N

    1990-09-01

    During October, 1987, 593 sera were collected from risk groups in Sudan's only major deepwater port, Port Sudan. The risk groups included prostitutes, lorry drivers and prisoners. A large proportion of the study participants practised high risk behaviour which included sexual promiscuity, medical treatment by injection, scarification and tattooing. Despite high risk behaviour and evidence of a high prevalence of hepatitis B infection, a virus transmitted in a manner similar to HIV, no study participants were positive for HIV infection. This data suggests that the prevalence of HIV infection amongst high risk groups in Port Sudan is very low. These findings confirm a lack of clinical cases of AIDS in hospitalized patients in Port Sudan and the small number of reported cases in other areas of northern Sudan. PMID:2253574

  17. Geometry of the southern San Andreas fault and its implications for seismic hazard

    NASA Astrophysics Data System (ADS)

    Langenheim, V. E.; Dorsey, R. J.; Fuis, G. S.; Cooke, M. L.; Fattaruso, L.; Barak, S.

    2015-12-01

    The southern San Andreas fault (SSAF) provides rich opportunities for studying the geometry and connectivity of fault stepovers and intersections, including recently recognized NE tilting of the Salton block between the SSAF and San Jacinto fault (SJF) that likely results from slight obliquity of relative plate motion to the strike of the SSAF. Fault geometry and predictions of whether the SSAF will rupture through the restraining bend in San Gorgonio Pass (SGP) are controversial, with significant implications for seismic hazard. The evolution of faulting in SGP has led to various models of strain accommodation, including clockwise rotation of fault-bounded blocks east of the restraining bend, and generation of faults that siphon strike slip away from the restraining bend onto the SJF (also parallel to the SSAF). Complex deformation is not restricted to the upper crust but extends to mid- and lower-crustal depths according to magnetic data and ambient-noise surface-wave tomography. Initiation of the SJF ~1.2 Ma led to formation of the relatively intact Salton block, and end of extension on the West Salton detachment fault on the west side of Coachella Valley. Geologic and geomorphic data show asymmetry of the southern Santa Rosa Mountains, with a steep fault-bounded SW flank produced by active uplift, and gentler topographic gradients on the NE flank with tilted, inactive late Pleistocene fans that are incised by modern upper fan channels. Gravity data indicate the basin floor beneath Coachella Valley is also asymmetric, with a gently NE-dipping basin floor bound by a steep SSAF; seismic-reflection data suggest that NE tilting took place during Quaternary time. 3D numerical modeling predicts gentle NE dips in the Salton block that result from the slight clockwise orientation of relative motion across a NE-dipping SSAF. A NE dip of the SSAF, supported by various geophysical datasets, would reduce shaking in Coachella Valley compared to a vertical fault.

  18. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  19. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  20. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  1. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  2. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  3. Declining sand dune activity in the southern Canadian prairies: Historical context, controls and ecosystem implications

    NASA Astrophysics Data System (ADS)

    Hugenholtz, Chris H.; Bender, Darren; Wolfe, Stephen A.

    2010-11-01

    Sandhills are islands of biodiversity in the southern Canadian prairies that sustain habitat for many rare and endangered species. These unique areas consist of large expanses of dune fields now mostly stabilized by grassland vegetation. Historically, the number of active dunes has decreased significantly due to vegetation stabilization, resulting in a dramatic decline of open-sand habitat for a variety of dune-dependent species. Without a certain level of wind erosion, opportunities for establishment of early-stage, species-rich vegetation types are diminished and open-sand habitat decreases by encroachment of the surrounding grassland vegetation. The current trend of dune stabilization, however, implies that wind erosion is decreasing, thereby threatening the continued existence of a variety of dune-dependent plants, arthropods and vertebrates, as well as other less-specialized species that benefit indirectly from these habitats. By reviewing factors contributing to the historical decline of active dunes, as well as the ecological implications of dune stabilization, the aim of this paper is to establish the biophysical context for new land management strategies that conserve valued landscape components, such as active dunes, and the processes therein. As dune stabilization continues management interventions will be required to sustain or re-establish open sand and the species that rely on these habitats.

  4. Agonistic behaviour in juvenile southern rock lobster, Jasus edwardsii (Decapoda, Palinuridae): implications for developing aquaculture

    PubMed Central

    Carter, Chris G.; Westbury, Heath; Crear, Bradley; Simon, Cedric; Thomas, Craig

    2014-01-01

    Abstract The Southern rock lobster, Jasus edwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasus edwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11), avoidance (6) and others (12). Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture. PMID:25561845

  5. Agonistic behaviour in juvenile southern rock lobster, Jasusedwardsii (Decapoda, Palinuridae): implications for developing aquaculture.

    PubMed

    Carter, Chris G; Westbury, Heath; Crear, Bradley; Simon, Cedric; Thomas, Craig

    2014-01-01

    The Southern rock lobster, Jasusedwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasusedwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11), avoidance (6) and others (12). Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture.

  6. Agonistic behaviour in juvenile southern rock lobster, Jasusedwardsii (Decapoda, Palinuridae): implications for developing aquaculture.

    PubMed

    Carter, Chris G; Westbury, Heath; Crear, Bradley; Simon, Cedric; Thomas, Craig

    2014-01-01

    The Southern rock lobster, Jasusedwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasusedwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11), avoidance (6) and others (12). Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture. PMID:25561845

  7. The question of Sudan: a hydro-economic optimization model for the Sudanese Blue Nile

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2015-05-01

    The effects of development and the uncertainty of a changing climate in eastern Africa pose myriad challenges for water managers along the Blue Nile. Sudan's large irrigation potential, hydroelectric dams, and prime location within the basin mean that Sudan's water management decisions will have great social, economic and political implications for the region. At the same time, Sudan's water use options are constrained by tradeoffs between upstream irrigation developments and downstream hydropower facilities as well as by the country's commitments under existing or future transboundary water sharing agreements. Here, we present a model that can be applied to evaluate optimal allocation of surface water resources to irrigation and hydropower in the Sudanese portion of the Blue Nile. Hydrologic inputs are combined with agronomic and economic inputs to formulate an optimization model within the General Algebraic Modeling System (GAMS). A sensitivity analysis is performed by testing model response to a range of economic conditions and to changes in the volume and timing of hydrologic flows. Results indicate that changing hydroclimate inputs have the capacity to greatly influence the productivity of Sudan's water resource infrastructure. Results also show that the economically optimal volume of water consumption, and thus the importance of existing treaty constraints, is sensitive to the perceived value of agriculture relative to electricity as well as to changing hydrological conditions.

  8. The question of Sudan: a hydroeconomic optimization model for the Sudanese Nile

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2014-10-01

    The effects of development and the uncertainty of a changing climate in East Africa pose myriad challenges for water managers along the Blue Nile. Sudan's large irrigation potential, hydroelectric dams, and prime location within the basin mean that Sudan's water management decisions will have great social, economic and political implications within the region. At the same time, Sudan's water use options are constrained by tradeoffs between upstream irrigation developments and downstream hydropower facilities as well as by the country's commitments under existing or future transboundary water sharing agreements. Here, we present a model that can be applied to evaluate optimal allocation of surface water resources to irrigation and hydropower in the Sudanese portion of the Blue Nile. Hydrologic inputs are combined with agronomic and economic inputs to formulate an optimization model within the General Algebraic Modeling System (GAMS). A sensitivity analysis is performed by testing model response to a range of economic conditions and to changes in the volume and timing of hydrologic flows. Results indicate that changing hydroclimate inputs have the capacity to greatly influence the productivity of Sudan's water resources infrastructure. Results also show that the economically optimal volume of water consumption, and thus the importance of existing treaty constraints, is sensitive to the perceived value of agriculture relative to electricity as well as to changing hydrological conditions.

  9. The ethnic distribution of sickle cell disease in Sudan

    PubMed Central

    Sabahelzain, Majdi Mohammed; Hamamy, Hanan

    2014-01-01

    Sickle cell disease (SCD) is one of the most common inherited disorders of haemoglobin in Africa and it is expected that sickle cell trait varies in frequency in different areas in Sudan. An extensive literature search was carried out accessing the US National Library of Medicine, the WHO Eastern Mediterranean Region resources, the Catalogue for Transmission Genetics in Arabs and papers and documents published in Sudan that included data on the prevalence of sickle cell anaemia and trait. Rates of SCA and trait varied in different areas in Sudan with the highest rates reported from Western and Eastern Sudan where one in every 123 children born in Messeryia tribe in Western Sudan is at risk of having SCD. High consanguinity rates and malaria endemicity are strong related factors with sickle cell gene in Sudan. This review will present what is known about the rates of sickle cell gene in different ethnic groups in Sudan. PMID:25360197

  10. Stratigraphic assessment of the Arcelia Teloloapan area, southern Mexico: implications for southern Mexico's post-Neocomian tectonic evolution

    NASA Astrophysics Data System (ADS)

    Cabral-Cano, E.; Lang, H. R.; Harrison, C. G. A.

    2000-10-01

    Stratigraphic assessment of the "Tierra Caliente Metamorphic Complex" (TCMC) between Arcelia and Teloloapan in southern Mexico, based on photo interpretation of Landsat Thematic Mapper images and field mapping at the 1:100,000 scale, tests different tectonic evolution scenarios that bear directly on the evolution of the southern North American plate margin. The regional geology, emphasizing the stratigraphy of a portion of the TCMC within the area between Arcelia and Teloloapan is presented. Stratigraphic relationships with units in adjacent areas are also described. The base of the stratigraphic section is a chlorite grade metamorphic sequence that includes the Taxco Schist, the Roca Verde Taxco Viejo Formation, and the Almoloya Phyllite Formation. These metamorphic units, as thick as 2.7 km, are covered disconformably by a sedimentary sequence, 2.9 km thick, composed of the Cretaceous marine Pochote, Morelos, and Mexcala Formations, as well as undifferentiated Tertiary continental red beds and volcanic rocks. The geology may be explained as the evolution of Mesozoic volcanic and sedimentary environments developed upon attenuated continental crust. Our results do not support accretion of the Guerrero terrane during Laramide (Late Cretaceous-Paleogene) time.

  11. Higher Education and Employment in the Sudan.

    ERIC Educational Resources Information Center

    Sanyal, Bikas C.; Yacoub, Sammani A.

    The increase in investment in education in the Sudan has increased the number of graduates by about 12 percent each year in 1970-1975. The increase in output has not been matched by an equal increase in the absorption capacity of the labor market. Postsecondary education has been extremely costly, and the nation can hardly support the problem of…

  12. Aetiology of Oral Cancer in the Sudan

    PubMed Central

    2013-01-01

    ABSTRACT Objectives To review the studied risk factors that linked to aetiology of oral cancer in the Sudan. There have been numerous reports in the increase in the incidence of oral cancer from various parts of the world. A recent trend for a rising incidence of oral cancer, with the absence of the well established risk factors, has raised concern. Although, there are inconsistent data on incidence and demographical factors, studies suggest that the physiologic response to risk factors by men and women vary in different populations. Material and Methods This review principally examines 33 publications devoted to aetiology of oral cancer in the Sudan, in addition to some risk factors that are commonly practiced in the Sudan. Results Several studies examining risk factors for oral cancer include tobacco use (Smoked and Smokeless), alcohol consumption, occupational risk, familial risk, immune deficits, virus infection and genetic factors. Conclusions Toombak use and infection with high risk Human Papilloma Virus (HPV) were extensively investigated and linked to the aetiology of oral cancer in Sudan. PMID:24422031

  13. Buried troughs, grabens and rifts in Sudan

    NASA Astrophysics Data System (ADS)

    Salama, R. B.

    The deep lineaments and shear patterns of Sudan follow two main directions :NNW (Red Sea trend) and ENE (Gulf of Aden trend). Precambrian mobile belts trend NE and NW. Palaezoic(?) sediments occupy NE-SW aligned grabens. Mesozoic continental sediments with NW paleotrends were deposited in two major depressions also aligned NW. Cainozoic uplift and volcanism was associated with domal uplifts along NE and SE axes. Fracturing and faulting in NW and NE directions resulted in the formation of NW-SE fault bounded grabens ranging in depth from 1 to 11 km. Extending from the western boundaries of Sudan to the eastern borders with Ethiopia, the Sudanese Cainozoic rift systemforms the largest rift system in Africa and includes: (a) Bahr E1 Arab Rift, (b) White Nile Rift, (c) Blue Nile Rift, (d) River Atbara Rift and (e) Wadi El Kuu Rift. The grabens and trouhs within the rift system form the main groundwater basins of Sudan. The discovery of oil in three of these rifts will encourage the exploration for oil in the others and a search for similar structures in the northern areas of Sudan.

  14. Political Implications of the Southern African Development Community Agenda on Educational Development in the Region.

    ERIC Educational Resources Information Center

    Nziramasanga, Caiphas T.

    This paper briefly describes the historical development of the Southern African Development Coordination Conference (SADCC) from its roots in 1980 and examines the work of the Southern African Development Community (SADC) today. The objectives of the SADCC are listed from the 1980 declaration and the achievement of those objectives are assessed.…

  15. The New South as Curriculum: Implications for Understanding Southern Race Relations.

    ERIC Educational Resources Information Center

    Castenell, Louis A.

    The culture of the southern United States is examined in the context of its effects on race relations and how it is portrayed in curriculum. Many of the southern racial tragedies of the past are still unresolved and this is reflected in schools as they teach about the South. Since schools are dependent on published materials to teach classes, and…

  16. Not just about sunburn--the ozone hole's profound effect on climate has significant implications for Southern Hemisphere ecosystems.

    PubMed

    Robinson, Sharon A; Erickson, David J

    2015-02-01

    Climate scientists have concluded that stratospheric ozone depletion has been a major driver of Southern Hemisphere climate processes since about 1980. The implications of these observed and modelled changes in climate are likely to be far more pervasive for both terrestrial and marine ecosystems than the increase in ultraviolet-B radiation due to ozone depletion; however, they have been largely overlooked in the biological literature. Here, we synthesize the current understanding of how ozone depletion has impacted Southern Hemisphere climate and highlight the relatively few documented impacts on terrestrial and marine ecosystems. Reviewing the climate literature, we present examples of how ozone depletion changes atmospheric and oceanic circulation, with an emphasis on how these alterations in the physical climate system affect Southern Hemisphere weather, especially over the summer season (December-February). These potentially include increased incidence of extreme events, resulting in costly floods, drought, wildfires and serious environmental damage. The ecosystem impacts documented so far include changes to growth rates of South American and New Zealand trees, decreased growth of Antarctic mosses and changing biodiversity in Antarctic lakes. The objective of this synthesis was to stimulate the ecological community to look beyond ultraviolet-B radiation when considering the impacts of ozone depletion. Such widespread changes in Southern Hemisphere climate are likely to have had as much or more impact on natural ecosystems and food production over the past few decades, than the increased ultraviolet radiation due to ozone depletion.

  17. Effect of iron supply on Southern Ocean CO2 uptake and implications for glacial atmospheric CO2.

    PubMed

    Watson, A J; Bakker, D C; Ridgwell, A J; Boyd, P W; Law, C S

    2000-10-12

    Photosynthesis by marine phytoplankton in the Southern Ocean, and the associated uptake of carbon, is thought to be currently limited by the availability of iron. One implication of this limitation is that a larger iron supply to the region in glacial times could have stimulated algal photosynthesis, leading to lower concentrations of atmospheric CO2. Similarly, it has been proposed that artificial iron fertilization of the oceans might increase future carbon sequestration. Here we report data from a whole-ecosystem test of the iron-limitation hypothesis in the Southern Ocean, which show that surface uptake of atmospheric CO2 and uptake ratios of silica to carbon by phytoplankton were strongly influenced by nanomolar increases of iron concentration. We use these results to inform a model of global carbon and ocean nutrients, forced with atmospheric iron fluxes to the region derived from the Vostok ice-core dust record. During glacial periods, predicted magnitudes and timings of atmospheric CO2 changes match ice-core records well. At glacial terminations, the model suggests that forcing of Southern Ocean biota by iron caused the initial approximately 40 p.p.m. of glacial-interglacial CO2 change, but other mechanisms must have accounted for the remaining 40 p.p.m. increase. The experiment also confirms that modest sequestration of atmospheric CO2 by artificial additions of iron to the Southern Ocean is in principle possible, although the period and geographical extent over which sequestration would be effective remain poorly known.

  18. Not just about sunburn--the ozone hole's profound effect on climate has significant implications for Southern Hemisphere ecosystems.

    PubMed

    Robinson, Sharon A; Erickson, David J

    2015-02-01

    Climate scientists have concluded that stratospheric ozone depletion has been a major driver of Southern Hemisphere climate processes since about 1980. The implications of these observed and modelled changes in climate are likely to be far more pervasive for both terrestrial and marine ecosystems than the increase in ultraviolet-B radiation due to ozone depletion; however, they have been largely overlooked in the biological literature. Here, we synthesize the current understanding of how ozone depletion has impacted Southern Hemisphere climate and highlight the relatively few documented impacts on terrestrial and marine ecosystems. Reviewing the climate literature, we present examples of how ozone depletion changes atmospheric and oceanic circulation, with an emphasis on how these alterations in the physical climate system affect Southern Hemisphere weather, especially over the summer season (December-February). These potentially include increased incidence of extreme events, resulting in costly floods, drought, wildfires and serious environmental damage. The ecosystem impacts documented so far include changes to growth rates of South American and New Zealand trees, decreased growth of Antarctic mosses and changing biodiversity in Antarctic lakes. The objective of this synthesis was to stimulate the ecological community to look beyond ultraviolet-B radiation when considering the impacts of ozone depletion. Such widespread changes in Southern Hemisphere climate are likely to have had as much or more impact on natural ecosystems and food production over the past few decades, than the increased ultraviolet radiation due to ozone depletion. PMID:25402975

  19. Avalonian crustal controls on basin evolution: implications for the Mesozoic basins of the southern North Sea

    NASA Astrophysics Data System (ADS)

    Smit, Jeroen; van Wees, Jan-Diederik; Cloetingh, Sierd

    2015-04-01

    Little is known of the Southern North Sea Basin's (SNSB) Pre-Permian basement due to a lack of outcrop and cores. The nature and structure of the East Avalonian crust and lithosphere remain even less constrained in the absence of deep seismic (refraction) lines. However, various studies have hinted at the importance of the Reactivation of the Early Carboniferous fault network during each consecutive Mesozoic and Cenozoic tectonic phase, demonstrating the key role of weak zones from the Early Carboniferous structural grain in partitioning of structural deformation and vertical basin motions at various scales. Although the older basin history and the basement attract increasing attention, the Pre-Permian tectonics of the SNSB remains little studied with most attention focused on the Permian and younger history. The strong dispersal of existing constraints requires a comprehensive study from Denmark to the UK, i.e. the East Avalonian microplate, bordered by the Variscan Rheïc suture, the Atlantic and Baltica. Based on an extensive literature study and the reinterpretation of publicly available data, linking constraints from the crust and mantle to stratigraphic-sedimentological information, we complement the map of Early Carboniferous rifting of East Avalonia and propose a new tectonic scenario. From the reinterpretation of the boundary between Avalonia and Baltica we propose a new outline for the Avalonian microplate with implications for the tectonics of the North German Basin. Furthermore, we highlight the nature and extent of the major crustal/lithospheric domains with contrasting structural behaviour and the major boundaries that separate them. Results shed light on the effects of long lived differences in crustal fabric that are responsible for spatial heterogeneity in stress and strain magnitudes and zonations of fracturing, burial history and temperature history. The geomechanical control of large crustal-scale fault structures will provide the constraints

  20. Rehabilitation of the expanded programme on immunization in Sudan following a poliomyelitis outbreak.

    PubMed Central

    ElZein, H. A.; Birmingham, M. E.; Karrar, Z. A.; Elhassan, A. A.; Omer, A.

    1998-01-01

    In 1993 a large outbreak of paralytic poliomyelitis occurred in Sudan as a result of an accumulation of large numbers of susceptible children that was accelerated by faltering immunization services. The extent of the outbreak led to the rapid rehabilitation of Sudan's Expanded Programme on Immunization (EPI); the government began financing vaccine purchase, operational aspects of EPI were decentralized, vaccine delivery was changed from a mobile to a fixed-site strategy, a solar cold chain network was installed, inservice training was resuscitated, and social mobilization was enhanced. National immunization days (NIDs) for poliomyelitis eradication were conducted throughout the country, including the southern states during a cease fire in areas of conflict. Measles immunization coverage was increased by offering measles vaccine during the second round of NIDs and subsequently through routine immunization services. Supplemental tetanus toxoid immunization of women of child-bearing age began in three provinces at high risk for neonatal tetanus. From 1994 to 1996 reported immunization coverage increased and the incidence of all EPI target diseases fell. Trends in coverage, disease incidence, financing, and the implementation of WHO-recommended disease-control strategies suggest that more sustainable immunization services have been re-established in Sudan. PMID:9803584

  1. Women's status and fertility in the Sudan.

    PubMed

    Saghayroun, A A

    1985-06-01

    This paper summarizes the history of women's education in Sudan; data on the relationship between their educational levels and fertility; and data on the relationship between fertility and women's employment. In general, the data point to an inverse relationship between the education of women and fertility. This relationship exists when considering the education of husbands. In terms of employment, women who report no work experience have the highest fertility, those who are self-employed or are family workers have an intermediate level of fertility, while those women who work for others have the lowest level of fertility. Education appears to be more closely associated with fertility than employment. The author concludes that as the status of women shifts to perceptions based on education and gainful employment, fertility will decline. However, in the Sudan, strong traditional values, based on women's roles related to childbearing and childrearing, will continue to sustain a relatively high fertility rate. (author's)

  2. Tectonic implications of the microearthquake seismicity and fault plane solutions in southern Peru

    NASA Technical Reports Server (NTRS)

    Grange, F.; Hatzfeld, D.; Cunningham, P.; Molnar, P.; Roecker, S. W.; Suarez, G.; Rodrigues, A.; Ocola, L.

    1984-01-01

    Because the contortion in the seismic zone in southern Peru is aligned approximately parallel to the direction of relative plate motion, rather than perpendicular to the coast of Peru, the position of the contortion need not migrate with respect to the overriding South American plate as the Nazca plate subducts beneath it, and the flow in the surrounding asthenosphere could be in a steady state. In addition, the position of the contortion defines the northern boundary of the volcanic arc in southern Peru. The inference that a wedge of asthenospheric material must overlie the downgoing slab for subduction-related volcanism to occur is thereby strengthened.

  3. Dissertation Citations in Organismal Biology at Southern Illinois University at Carbondale: Implications for Collection Development

    ERIC Educational Resources Information Center

    Nabe, Jonathan; Imre, Andrea

    2008-01-01

    We report on a citation analysis of Ph.D. dissertations in plant biology and zoology at Southern Illinois University Carbondale, undertaken to test the common assumption that scientists favor current research to such an extent that journal backfiles can be de-emphasized in academic library collections. Results demonstrate otherwise. The study is…

  4. Revisiting atmospheric dust export to the Southern Hemisphere ocean: Biogeochemical implications

    NASA Astrophysics Data System (ADS)

    Wagener, Thibaut; Guieu, CéCile; Losno, RéMi; Bonnet, Sophie; Mahowald, Natalie

    2008-06-01

    Aerosol concentrations in the Southern Hemisphere are largely undersampled. This study presents a chemical and physical description of dust particles collected on board research vessels in the southeast Pacific (SEPS) and the Southern Ocean (SOKS). Concentrations of dust were 6.1 ± 2.4 ng m-3 for SEPS and 13.0 ± 6.3 ng m-3 for SOKS. Dust fluxes, derived from those concentrations, were 9.9 ± 3.7 μg m-2 d-1 for SEPS and 38 ± 14 μg m-2 d-1 for SOKS and are shown to be representative of actual fluxes in those areas. Dust and iron deposition are up to 2 orders of magnitude lower than former predictions. A map of dust deposition on the Southern Hemisphere is proposed by incorporating those in situ measurements into a dust model. This study confirms that dust deposition is not the dominant source of iron to the large high-nutrient low-chlorophyll Southern Ocean.

  5. Lead isotopes in Southern Ocean marine sediments: implications for paleoclimatic provenance and seawater studies

    NASA Astrophysics Data System (ADS)

    Cook, C. P.; Martin, E. E.

    2014-12-01

    Lead (Pb) isotopes in detrital marine sediments and authigenic oxide coatings have proven useful in reconstructing past changes in continental weathering of glaciated continents and ocean circulation. This approach is under-utilised in the Southern Ocean, despite uncertainties about the evolution of Antarctica's ice sheets and oceanographic changes in this region throughout the Cenozoic. Lead isotopes in sediments are controlled by the mineralogy and age of their bedrock sources, making them an ideal tool to trace changes in Southern Ocean sediment provenance associated with onland erosion patterns (and ice sheet variability), and ocean circulation. However, core-top mapping of Pb isotope signatures of detrital marine sediments in this region is non-existent. We present new Pb isotope data for acid-digested <63µm and bulk Late Holocene sediments from 40 cores located in the East Antarctic sector of Southern Ocean. Results demonstrate that, similar to existing Nd and Sr core-top surveys, distinct provenance sectors can be seen in sediments proximal to the continent, due to the geological characteristics of bedrock sources along the margin. A striking N-S trend is also evident, with distal sediments characterised by less radiogenic isotopic signatures, likely associated with a decrease in radiogenic Pb-bearing minerals with increasing distance from the continental margin. This pattern suggests that Pb isotopes in marine sediments may be useful in reconstructing past provenance trends associated with ice sheet change, and migrations of Southern Ocean frontal positions. In addition, we will present new seawater Pb isotope data from reductive leaching of authigenic coatings of these same sediments, permitting for Late Holocene Pb isotope seawater mapping of the Southern Ocean. To ensure we measured the true seawater signal, we adapted established sequential leaching procedures to minimise detrital contamination, and monitored leachate compositions with Nd isotopes, and

  6. Shape of the subducted Rivera and Cocos plates in southern Mexico: Seismic and tectonic implications

    NASA Astrophysics Data System (ADS)

    Pardo, Mario; SuáRez, Gerardo

    1995-07-01

    The geometry of the subducted Rivera and Cocos plates beneath the North American plate in southern Mexico was determined based on the accurately located hypocenters of local and teleseismic earthquakes. The hypocenters of the teleseisms were relocated, and the focal depths of 21 events were constrained using a body wave inversion scheme. The suduction in southern Mexico may be approximated as a subhorizontal slab bounded at the edges by the steep subduction geometry of the Cocos plate beneath the Caribbean plate to the east and of the Rivera plate beneath North America to the west. The dip of the interplate contact geometry is constant to a depth of 30 km, and lateral changes in the dip of the subducted plate are only observed once it is decoupled from the overriding plate. On the basis of the seismicity, the focal mechanisms, and the geometry of the downgoing slab, southern Mexico may be segmented into four regions: (1) the Jalisco region to the west, where the Rivera plate subducts at a steep angle that resembles the geometry of the Cocos plate beneath the Caribbean plate in Central America; (2) the Michoacan region, where the dip angle of the Cocos plate decreases gradually toward the southeast, (3) the Guerrero-Oaxaca region, bounded approximately by the onshore projection of the Orozco and O'Gorman fracture zones, where the subducted slab is almost subhorizontal and underplates the upper continental plate for about 250 km, and (4) the southern Oaxaca and Chiapas region, in southeastern Mexico, where the dip of the subduction gradually increases to a steeper subduction in Central America. These drastic changes in dip do not appear to take place on tear faults, suggesting that smooth contortions accommodate these changes in geometry. The inferred 80 and 100 km depth contours of the subducted slab lie beneath the southern front of the Trans-Mexican Volcanic Belt, suggesting it is directly related to the subduction. Thus the observed nonparallelism with the Middle

  7. Reasons behind the Failure of Teaching Sudan Practical Integrated National English (SPINE 5) in Sudan

    ERIC Educational Resources Information Center

    Hamad, Mona M.

    2015-01-01

    According to the development of English language learning and curriculum design, English language series became a very important issue that affects education globally and in Sudan. In specific, this study reports reasons behind the failure of teaching SPINE 5 (which is one of SPINE series) from the teachers' point of view. In Bahry Locality in…

  8. Savanna burning and convective mixing in southern Africa - Implications for CO emissions and transport

    NASA Technical Reports Server (NTRS)

    Connors, Vickie S.; Cahoon, Donald R., Jr.; Reichle, Henry G.; Brunke, Ernst-Gunther; Garstang, Michael; Seiler, Wolfgang; Scheel, H. E.

    1991-01-01

    Atmospheric data from both remote and direct measurements were used to compute the carbon monoxide (CO) emissions and mass transport from Africa south of the equator. The Measurement of Air Pollution from Satellites (MAPS) experiment flew on the Space Shuttle during October 5-13, 1984; the highest CO mixing ratios from the entire mission were measured over southern Africa. In addition to the MAPS data, surface CO mixing ratios were measured in the boundary layer at Cape Point, South Africa. A calibration factor for the remote MAPS CO measurements was determined by computing the ratio of the surface measurements from Cape Point during unpolluted periods to coincident MAPS measurements. The adjusted MAPS CO data were then used to compute the mass flux of CO from biomass burning in southern Africa during the MAPS mission. The transport calculations were compared to the estimated CO emissions from biomass burning to examine the efficiency in which the continental tropical clouds redistribute CO in the troposphere.

  9. Present-day shortening in Southern Haiti from GPS measurements and implications for seismic hazard

    NASA Astrophysics Data System (ADS)

    Symithe, Steeve; Calais, Eric

    2016-06-01

    The ~ 3 M inhabitant capital region of Haiti, severely affected by the devastating January 12, 2010, M7.0 earthquake, continues to expand at a fast rate. Accurate characterization of regional earthquake sources is key to inform urban development and construction practices through improved regional seismic hazard estimates. Here we use a recently updated Global Positioning System (GPS) data set to show that seismogenic strain accumulation in southern Haiti involves an overlooked component of shortening on a south-dipping reverse fault along the southern edge of the Cul-de-Sac basin, in addition to the well-known component of left-lateral strike-slip motion. This tectonic model implies that ground shaking may be twice that expected if the major fault was purely strike-slip, as assumed in the current seismic hazard map for the region.

  10. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: (1) Provision of legal advice and counseling to the Government of Sudan, to a person in Sudan, or in... the laws of any jurisdiction within the United States, provided that such advice and counseling is not..., arbitration, or administrative proceedings; (3) Initiation of domestic U.S. legal, arbitration,...

  11. Glacial-interglacial variability in diatom abundance and valve size: Implications for Southern Ocean paleoceanography

    NASA Astrophysics Data System (ADS)

    Nair, Abhilash; Mohan, Rahul; Manoj, M. C.; Thamban, Meloth

    2015-10-01

    Antarctic sea ice extent along with Southern Ocean biological productivity varied considerably during glacial-interglacial periods, and both are known to have played a considerable role in regulating atmospheric CO2 variations in the past. Here we present data on diatom absolute abundance (valves/g of sediment) and size over the past ~ 42 ka B.P. and how they link to glacial-interglacial changes in Antarctic sea ice extent, Southern Ocean frontal systems, and aeolian dust flux. Our records of sea ice and permanent open ocean zone diatom abundances suggest a shift in the Antarctic winter sea ice limit and Polar Front respectively up to the modern-day Polar Frontal Zone during marine isotopic stages (MIS) 2 and late MIS 3. In addition to glacial shifts in the Polar Front, diatom assemblages also recorded a plausible northward shifts in Polar Front during few intervals of MIS 1. Glacial periods north of the Polar Front in the Indian sector of the Southern Ocean were characterized by higher total diatom abundance, larger Fragilariopsis kerguelensis apical length, and Thalassiosira lentiginosa radius. This is probably a consequence of (1) a northward expansion of the opal belt, a region characterized by high production and export of biogenic silica; (2) an increase in terrigenous input, via erosion of Crozet Islands; and (3) the alleviation of iron deficit by high input of Fe-bearing dust. The larger and highly silicified diatoms such as F. kerguelensis and T. lentiginosa may have mainly contributed in transporting biogenic silica and organic carbon to the seabed for the last 42 ka, in the northern Polar Frontal Zone of the Indian sector of the Southern Ocean.

  12. Forest to agriculture conversion in southern Belize: Implications for migrant land birds

    USGS Publications Warehouse

    Spruce, J.P.; Dowell, B.A.; Robbins, C.S.; Sader, S.A.; Doyle, Jamie K.; Schelhas, John

    1993-01-01

    Central America offers a suite of neotropical habitats vital to overwintering migrant land birds. The recent decline of many forest dwelling avian migrants is believed to be related in part to neotropical deforestation and land use change. However, spatio-temporal trends in neotropical habitat availability and avian migrant habitat use are largely unknown. Such information is needed to assess the impact of agriculture conversion on migrant land birds. In response, the USDI Fish and Wildlife Service and the University of Maine began a cooperative study in 1988 which applies remote sensing and field surveys to determine current habitat availability and avian migrant habitat use. Study sites include areas in Belize, Costa Rica, Guatemala and southern Mexico. Visual assessment of Landsat TM imagery indicates southern Belize forests are fragmented by various agricultural systems. Shifting agriculture is predominant in some areas, while permanent agriculture (citrus and mixed animal crops) is the primary system in others. This poster focuses on efforts to monitor forest to agriculture conversion in southern Belize using remote sensing, field surveys and GIS techniques. Procedures and avian migrant use of habitat are summarized.

  13. Mapping the potential risk of mycetoma infection in Sudan and South Sudan using ecological niche modeling.

    PubMed

    Samy, Abdallah M; van de Sande, Wendy W J; Fahal, Ahmed Hassan; Peterson, A Townsend

    2014-10-01

    In 2013, the World Health Organization (WHO) recognized mycetoma as one of the neglected tropical conditions due to the efforts of the mycetoma consortium. This same consortium formulated knowledge gaps that require further research. One of these gaps was that very few data are available on the epidemiology and transmission cycle of the causative agents. Previous work suggested a soil-borne or Acacia thorn-prick-mediated origin of mycetoma infections, but no studies have investigated effects of soil type and Acacia geographic distribution on mycetoma case distributions. Here, we map risk of mycetoma infection across Sudan and South Sudan using ecological niche modeling (ENM). For this study, records of mycetoma cases were obtained from the scientific literature and GIDEON; Acacia records were obtained from the Global Biodiversity Information Facility. We developed ENMs based on digital GIS data layers summarizing soil characteristics, land-surface temperature, and greenness indices to provide a rich picture of environmental variation across Sudan and South Sudan. ENMs were calibrated in known endemic districts and transferred countrywide; model results suggested that risk is greatest in an east-west belt across central Sudan. Visualizing ENMs in environmental dimensions, mycetoma occurs under diverse environmental conditions. We compared niches of mycetoma and Acacia trees, and could not reject the null hypothesis of niche similarity. This study revealed contributions of different environmental factors to mycetoma infection risk, identified suitable environments and regions for transmission, signaled a potential mycetoma-Acacia association, and provided steps towards a robust risk map for the disease. PMID:25330098

  14. The impact of war on women and children: case study of Sudan.

    PubMed

    El-nagar, S E

    1992-06-01

    Civil war has raged in southern Sudan from 1955 to 1972 and again from 1983 to the present. This situation has been compounded by regional conflicts in other parts of Sudan and wars in neighboring countries. The consequences of war are taking their toll on the entire region and are intensified by environmental hazards, desertification, drought, and famine. The socioeconomic and educational infrastructure has been destroyed in southern Sudan, taking the family support system with it. The atmosphere of continued fighting has made it all but impossible for relief agencies to provide services. The innocent victims of the war are civilians who are forced to choose between disastrous alternatives: if they flee, they lose their homes, their livelihoods, and their communities; if they stay, they watch these things being destroyed around them. Women and children are suffering the most. Hunger and disease are widespread, and immunization programs have been curtailed. Very few school-age children are receiving an education, and children are subject to kidnapping and abuse from soldiers. There may be as many as 3 million people displaced, with 1.5 million living in settled areas and 707,000 in camps in the Khartoum area. Relief aid in the camps is unreliable, and the displace women arrive with no assets or skills. They survive through domestic work, begging, petty trading, or beer-brewing and prostitution (the latter 2 are illegal). Children are left to fend for themselves all day or to find work in situations where they are exploited. In addition to depriving the children of their health, education, and economic stability, the war has resulted in cultural deprivation as ethnic groups lose their sense of identity. Psychological problems are the natural consequence of this situation, and aggressive behavior is seen in the displaced children, while trauma and anxiety plague the children in the war zones.

  15. U-Pb Detrital Zircon Geochronology and Implications: the Mesozoic southern Ordos Basin, North Central China

    NASA Astrophysics Data System (ADS)

    Xie, X.; Heller, P. L.; Chamberlain, K. R.

    2007-12-01

    Two deformation belts -- the Qinling orogenic belt (QOB) to the south and the Western Liupanshan thrust belt (WLTB) to the west, including the Qilian-Qaidam terrane (QQT) -- control the evolution of the southern Ordos Basin during early Mesozoic time. U-Pb detrital zircon geochronology is used to identify provenance, reconstruct paleogeography, and document the relative timing of basin margin deformation. Two correlated strata same age samples of the Middle to Late Triassic Yanchang Fm. were collected from the southern and southwestern basin margin respectively. In total 258 zircon grains were analyzed using LA-ICP-MS. Three major age populations -- 240-490 Ma, 1.8-2.0 Ga, and 2.2-2.8 Ga -- characterize the detrital zircon grains of the Yanchang Fm. Regional geochronology studies show that the two oldest age groups match ages of basement rocks found in the underlying North China block. The younger age group can be subdivided into three distinctive groups: 240-300 Ma, 300-400, and 400-490 Ma. The youngest age group matches ages exposed to the west in the QQT, whereas the other two match grains from southern QOB source. In all samples detrital zircon from the WLTB source area overwhelms the QOB source, regardless of its proximity to either basin margin. This result suggests that either the source rock with the youngest zircon grains (e.g. 240- 490 Ma) from the QOB to the south have been eroded away and no longer existed, or simply the QOB, even during deformation, was never the dominant source of detrital zircon to the southern Ordos Basin. Probably some drainage systems far from the west combine with some local tributary systems from the south control the sedimentation in the south Ordos Basin during the middle to Late Triassic time. This is surprising in that most studies suggest that the QOB was a longer lived and more dominant tectonic feature in this part of China during early Mesozoic time. Furthermore, it also indicates that: 1) deformation in the QOB and WLTB

  16. Dracunculiasis Eradication: And Now, South Sudan

    PubMed Central

    Hopkins, Donald R.; Ruiz-Tiben, Ernesto; Weiss, Adam; Withers Jr., P. Craig; Eberhard, Mark L.; Roy, Sharon L.

    2013-01-01

    This report summarizes the status of the global Dracunculiasis Eradication Program as of the end of 2012. Dracunculiasis (Guinea worm disease) has been eliminated from 17 of 21 countries where it was endemic in 1986, when an estimated 3.5 million cases occurred worldwide. Only 542 cases were reported from four countries in 2012, and 103 villages still had indigenous transmission. Most remaining cases were reported from the new Republic of South Sudan, whereas Chad, Ethiopia, and Mali each reported 10 cases or less. Political instability and insecurity in Mali may become the main obstacles to interrupting dracunculiasis transmission forever. PMID:23843492

  17. Prediction of temperature and precipitation in Sudan and South Sudan by using LARS-WG in future

    NASA Astrophysics Data System (ADS)

    Chen, Hua; Guo, Jiali; Zhang, Zengxin; Xu, Chong-Yu

    2013-08-01

    Global warming has brought great pressure on the environment and livelihood conditions in Sudan and South Sudan. It is desirable to analyze and predict the change of critical climatic variables, such as temperature and precipitation, which will provide valuable reference results for future water resources planning and management in the region. The aims of this study are to test the applicability of the Long Ashton Research Station Weather Generator (LARS-WG) model in downscaling daily precipitation and daily maximum (Tmax) and daily minimum (Tmin) temperatures in Sudan and South Sudan and use it to predict future changes of precipitation; Tmin and Tmax for nine stations in Sudan and South Sudan are based on the SRA2 scenario of seven General Circulation Models (GCMs) outputs for the periods of 2011-2030, 2046-2065, and 2080-2099. The results showed that (1) the LARS-WG model produces good performance in downscaling daily precipitation and excellent performance in downscaling Tmax and Tmin in the study region; (2) downscaled precipitation from the prediction of seven GCMs showed great inconsistency in these two regions, which illustrates the great uncertainty in GCMs' results in the regions; (3) predicted precipitation in rainy season JJA (June, July, and August) based on the ensemble mean of seven GCMs showed a decreasing trend in the periods of 2011-2030, 2046-2065, and 2080-2099 in Sudan; however, an increasing trend can be found in SON (September, October, and November) in the future; (4) precipitation in South Sudan has an increasing trend in most seasons in the future except in MAM (March, April, and May) season in 2011-2030; and (5) predictions from seven GCMs showed a similar and continuous increasing trend for Tmax and Tmin in all three future periods, which will bring severe negative influence on improving livelihoods and reducing poverty in Sudan and South Sudan.

  18. The Southern Survey of Agricultural Majors: Some Implications for the Future of Higher Education in Agriculture.

    ERIC Educational Resources Information Center

    Cosby, Arthur G.

    The increased enrollment of women in Colleges of Agriculture has implications for the training and socializing of agriculture professionals in the future. The female students represent fundamental changes in the character of agricultural enrollment. They are more likely to be young, single, and politically moderate or liberal. They are less likely…

  19. Compositional heterogeneity of Asteroid 4 Vesta’s southern hemisphere: Implications for the Dawn mission

    NASA Astrophysics Data System (ADS)

    Reddy, Vishnu; Gaffey, Michael J.; Kelley, Michael S.; Nathues, Andreas; Li, Jian-Yang; Yarbrough, Robert

    2010-12-01

    High signal-to-noise, rotationally-resolved spectra of Asteroid 4 Vesta's southern hemisphere from the 2007 opposition were used to constrain its compositional and mineralogical variations. The spectra were rotationally-phased using closely timed HST observations of Vesta by Li et al. (Li, J.-Y., McFadden, L.A., Thomas, P.C., Mutchler, M.J., Parker, J.Wm., Young, E.F., Russell, C.T., Sykes, M.V., Schmidt, B.E. [2010]. Icarus 208, 238-251). The average surface of Vesta's southern hemisphere is analogous to a howardite or polymict eucrite assemblage similar to the northern hemisphere, although the band parameters are distinctly shifted towards the diogenite zone on the Band-Band plot. A few distinct compositional units were detected and they might be related to albedo features detected by Hubble Space Telescope (Li et al., 2010). We have identified two compositionally distinct regions overlaying the background surface. The first unit is a polymict eucrite and/or low-Ca eucrite compositional unit at 143° longitude that border the eucrite zone on the Band-Band plot and the second is a diogenite unit at 159°. While we did not detect any distinct olivine units as suggested by Gaffey (Gaffey, M.J. [1997]. Icarus 127, 130-157), we cannot rule out the possibility of smaller olivine-rich units that are below the detection limit of the instrumentation we used. Based on the analysis and the limitations of the data, we do not suggest that Vesta's surface is olivine-free. Mean pyroxene chemistry estimates for both hemispheres broadly agree with one another (to within one-sigma) with the northern hemisphere ferrosilite (Fs) and wollastonite (Wo) values being slightly higher than southern hemisphere.

  20. 3D Body Wave Velocity Tomography in Southern Peru: Seismotectonic Implications

    NASA Astrophysics Data System (ADS)

    Gallego, A.; Perez, J.; David, C.; Comte, D.; Charrier, R.; Dorbath, L.

    2004-12-01

    The studied region corresponds to the southern segment of the 1868 rupture area, that did not break with the last Mw=8.4 Arequipa earthquake in southern Peru. A temporary network of 19 short period, continuous recording seismic stations was deployed (16.5° -18.5° S; 69.5° -72° W) between December 2002-March 2003 in this region. The 1093 select events were used for a joint hypocentral and velocity structure inversion. The first obtained 1D velocity model was used as the initial model for the 3D inversion, consisting in 231 blocks distributed along layers separated by 10 km for depths lower than 80 km, and by 20 km for depths between 80 and 160 km. North of the Arica Bend, between the Coast and Andean Range the high Vp velocity and Vp/Vs ratio observed at depths lower than 10 km could represent the Precambrian basement uplifted by the Incapuquio sinistral fault system, which develops a positive flower structure typical for transpressional zones, that raised the basement. This behavior is in good agreement with the uplift of the Cambrian metamorphic complex, in the Precordillera south of the Arica Bend (northern Chile), by the west-vergent thrust system. Beneath the anomalous high velocities (between 20 and 30 km depth), a low velocity zone (Vp<4.5 km/s, and Vp/Vs<1.5) can be observed; this LVZ can be associated with a zone of continuous metamorphism and/or partial melting that the decouples the upper-crustal imbrication from a thickening lower-crust. The Wadati-Benioff zone exhibits a dip angle of about 20° between 10 to 60 km depth, and about 45° for depths higher than 80 km. The double seismic zone known for northern Chile is not present in southern Peru. Cross sections perpendicular to the trench, define a very active seismic zone which dips about 45° trenchward, and is almost perpendicular to the subducting slab between 0 and 60 km depths, similar to the one existing in northern Chile, but with a lower rate of seismicity; the higher activity of this zone

  1. Orbital remote sensing for geological mapping in southern Tunisia: Implication for oil and gas exploration

    NASA Astrophysics Data System (ADS)

    Peña, Sherrie A.; Abdelsalam, Mohamed G.

    2006-02-01

    Southern Tunisia is dominated by early to middle Triassic continental sandstones inter-bedded with shales and conglomerates followed by late Triassic shallow marine carbonates, lower Jurassic evaporates, and upper Jurassic to lower Cretaceous clastic sedimentary rocks. These constitute the Dahar Plateau (which is part of the Ghadames Basin and it is the focus of this study) that was developed in association with regional uplift of the Saharan Platform. Efforts in mapping the details of surface geology in southern Tunisia are hindered by the lack of continuous bedrock outcrops, where some of the formations are buried under the sand of the Sahara Desert. Remote sensing data including multi-spectral optical (Landsat Enhanced Thematic Mapper (ETM+) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)), radar (RADARSAT), and Digital Elevation Models (DEMs) extracted from the Shuttle Radar Topography Mission (SRTM) data are used to trace along strike continuity of different lithological units as well as mapping morphologically defined structures in southern Tunisia. Landsat ETM+ and ASTER Red-Green-Blue (RGB) color combination images (both band and band-ratio images) have been used for the identification of various lithological units when they are exposed on the surface. On the other hand, RADARSAT images have been utilized for tracing geological formations and geological structures that are buried under thin (˜1 m) sand. Fusion of optical and radar remote sensing data using Color Normalization Transformation (CNT) has been effectively implemented to further identify lithological units and geological structures. Hill-shading techniques are applied to SRTM DEMs to enhance terrain perspective views and to extract geomorphological features and morphologically defined structures through the means of lineament analysis. Results from remote sensing analysis are in good agreement with results obtained from in situ investigations including geological

  2. Structural development of the southern basin, onshore Trinidad: Implications for hydrocarbon entrapment

    SciTech Connect

    Aden, L.J.; Bierley, R.E.

    1996-08-01

    Episodic compressional deformation across onshore southern Trinidad formed a complex spectrum of fold timing and fold types. Successful oil traps are not related to a specific time interval of structural formation, a specific oil expulsion event or a specific fold morphology. Traps that retained hydrocarbons may be related to seal facies. The tectono-stratigraphic section of onshore southern Trinidad, south of the Central Ranges, is comprised of three generalized depositional packages. Firstly, a southerly sourced Cretaceous to late Oligocene passive margin sequence of deepwater sands, shales and marls; secondly, a northerly sourced late Oligocene through middle Miocene syntectonic sequence of shallow to deep-water sands and shales; and thirdly, a west-southwesterly sourced late Miocene through Pleistocene shelfal sequence. Observations of compressional structures that folded these sediments during an early period of compressional deformation 25-10 million years before present suggest that all mudrock lithofacies could act as effective seals and trap hydrocarbons. Subsequent structural modification that occurred during a late period of compressional deformation between 5 million years and present day caused refolding and refaulting of these traps. Restructured traps that were sealed by brittle, Mesozoic deep-water facies failed and hydrocarbons migrated to shallower structural levels. Restructured folds that were sealed by ductile, Tertiary shallow-water facies retained trap fill.

  3. Salp/krill interactions in the Southern Ocean: spatial segregation and implications for the carbon flux

    NASA Astrophysics Data System (ADS)

    Pakhomov, E. A.; Froneman, P. W.; Perissinotto, R.

    Available data on the spatial distribution and feeding ecophysiology of Antarctic krill, Euphausia superba, and the tunicate, Salpa thompsoni, in the Southern Ocean are summarized in this study. Antarctic krill and salps generally display pronounced spatial segregation at all spatial scales. This appears to be the result of a clear biotopical separation of these key species in the Antarctic pelagic food web. Krill and salps are found in different water masses or water mass modifications, which are separated by primary or secondary frontal features. On the small-scale (<100 km), Antarctic krill and salps are usually restricted to the specific water parcels, or are well segregated vertically. Krill and salp grazing rates estimated using the in situ gut fluorescence technique are among the highest recorded in the Antarctic pelagic food web. Although krill and salps at times may remove the entire daily primary production, generally their grazing impact is moderate (⩽50% of primary production). The regional ecological consequences of years of high salp densities may be dramatic. If the warming trend, which is observed around the Antarctic Peninsula and in the Southern Ocean, continues, salps may become a more prominent player in the trophic structure of the Antarctic marine ecosystem. This likely would be coupled with a dramatic decrease in krill productivity, because of a parallel decrease in the spatial extension of the krill biotope. The high Antarctic regions, particularly the Marginal Ice Zone, have, however, effective physiological mechanisms that may provide protection against the salp invasion.

  4. Hyperpycnal sediment discharge from semiarid southern California rivers: Implications for coastal sediment budgets

    USGS Publications Warehouse

    Warrick, J.A.; Milliman, John D.

    2003-01-01

    Southern California rivers discharge hyperpycnal (river density greater than ocean density) concentrations of suspended sediment (>40 g/L, according to buoyancy theory) during flood events, mostly during El Nin??o-Southern Oscillation (ENSO) conditions. Because hyperpycnal river discharge commonly occurs during brief periods (hours to occasionally days), mean daily flow statistics often do not reveal the magnitude of these events. Hyperpycnal events are particularly important in rivers draining the Transverse Range and account for 75% of the cumulative sediment load discharged by the Santa Clara River over the past 50 yr. These events are highly pulsed, totaling only ??? 30 days (??? 0.15% of the total 50 yr period). Observations of the fate of sediment discharge, although rare, are consistent with hyperpycnal river dynamics and the high likelihood of turbidity currents during these events. We suggest that much of the sediment load initially bypasses the littoral circulation cells and is directly deposited on the adjacent continental shelf, thus potentially representing a loss of immediate beach sand supply. During particularly exceptional events (>100 yr recurrence intervals), flood underflows may extend past the shelf and escape to offshore basins.

  5. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened.

  6. An increase of dry season length over southern Amazonia, its causes and implication to climate projection

    NASA Astrophysics Data System (ADS)

    Fu, R.; Yin, L.

    2013-05-01

    Observations from several independent sources suggest that the dry season length (DSL) has increased over southern Amazonia since 1979, primarily due to a delay of its ending dates (DSE). Whether such a change is entirely due to natural climate variability or a result of combine natural variability and anthropogenic forced change will be assessed through a process-based analysis. The observed changes appear to be greater than those simulated by the global climate models that participated in the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5) forced by both historical and future anthropogenic and natural forcing. Such a discrepancy is unlikely due to under-representation of natural variability and more likely due to underestimate the sensitivity of the dry season length to external forcing. Consequently, the climate projections of these models may underestimate the future changes of the dry season length and its impact on rainforests. Our study suggests that it is imperative that monitoring, quantification, and understanding of changes of rainfall seasonality over southern Amazonia be improved.

  7. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened. PMID:25929961

  8. Phylogeography and spatial genetic structure of the Southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, M.P.; Haig, S.M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders. ?? The American Genetic Association. 2006. All rights reserved.

  9. Spatial genetic structure and regional demography in the southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, Mark P.; Haig, Susan M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders.

  10. Lateral extrusion of Tunisia : Contribution of Jeffara Fault (southern branch) and Petroleum Implications

    NASA Astrophysics Data System (ADS)

    Ghedhoui, R.; Deffontaines, B.; Rabia, M. C.

    2012-04-01

    Contrasting to the northward African plate motion toward Eurasia and due to its geographic position in the North African margin, since early cretaceous, Tunisia seems to be submitted to an eastward migration. The aim of this work is to study the southern branch of this inferred tectonic splay that may guide the Tunisian extrusion characterised to the east by the Mediterranean sea as a free eastern boundary. The Jeffara Fault zone (southern Tunisia), represent a case example of such deformation faced by Tunisia. Helped by the results of previous researchers (Bouaziz, 1995 ; Rabiaa, 1998 ; Touati et Rodgers, 1998 ; Sokoutis D. et al., 2000 ; Bouaziz et al., 2002 ; Jallouli et al., 2005 ; Deffontaines et al., 2008…), and new evidences developed in this study, we propose a geodynamic Tunisian east extrusion model, due to such the northern African plate migration to the Eurasian one. In this subject, structural geomorphology is undertaken herein based on both geomorphometric drainage network analysis (Deffontaines et al., 1990), the Digital Terrain Model photo-interpretation (SRTM) combined with photo-interpretation of detailed optical images (Landsat ETM+), and confirmed by field work and numerous seismic profiles at depth. All these informations were then integrated within a GIS (Geodatabase) (Deffontaines 1990 ; Deffontaines et al. 1994 ; Deffontaines, 2000 ; Slama, 2008 ; Deffontaines, 2008) and are coherent with the eastern extrusion of the Sahel block. We infer that the NW-SE Gafsa-Tozeur, which continue to the Jeffara major fault zone acting as a transtensive right lateral motion since early cretaceous is the southern branch of the Sahel block extrusion. Our structural analyses prove the presence of NW-SE right lateral en-echelon tension gashes, NW-SE aligned salt diapirs, numerous folds offsets, en-echelon folds, and so on that parallel this major NW-SE transtensive extrusion fault zone.These evidences confirm the fact that the NW-SE Jeffara faults correspond

  11. Recurrence, Rates, and Paleogeodetic Implications: Southern Cascadia Subduction Zone, Northern California

    NASA Astrophysics Data System (ADS)

    Leroy, T. H.; Patton, J. R.

    2010-12-01

    Earthquake and tsunami hazard for northern California and southern Oregon is dominated by estimates of recurrence for earthquakes on the Cascadia subduction zone (CSZ) and upper plate thrust faults. Recurrence interval (RI)estimates derived from site based terrestrial data (270-1,370 years) are inconsistent with the regional marine record of great earthquakes (RI = ~240 years). Reconciling these differences reveals information regarding different sources or magnitudes of coseismic or interseismic deformation in the southern CSZ. Early paleoseismic investigations utilized bulk peat for 14C age determinations and lack vertical elevation control. All terrestrial data sets are compiled, evaluated, ranked, and excluded according to their paleoseismic relevance. We construct an OxCal age model to evaluate the discriminated 14C based space-time relations graphically and statistically. We interpret a regional timing of tectonic deformation that is consistent with the timing of the marine record. Not all events are observed in each region and not all events have age control. Some regions lack cores representing the complete modern tidal elevation range (biasing the paleoseismic record). For example, when individual sites in the same region are combined, a more complete record of coseismic subsidence can be assumed, reducing the terrestrial RI to 360+-40, yet still longer than the marine RI. We consider relative sea-level (RSL), as the relation between land-level and sea-level and we find that chronologically distinct buried soils are found in settings segregated by elevation. Subsidence in southern Humboldt Bay occurred in positions of higher RSL at ~1,500, 2,200, and ~3,500 cal yrs BP. We pose that the RSL position does not relate to the time preceding the earthquake, but may relate to the accumulated strain at the time of the earthquake. RSL with a higher position would correspond with more accumulated strain in the upper plate. We evaluate the various factors that may

  12. Large scale screening for haemoglobin disorders in southern Vietnam: implications for avoidance and management.

    PubMed

    O'Riordan, Sean; Hien, Tran Tinh; Miles, Katie; Allen, Angela; Quyen, Nguyen Ngoc; Hung, Nguyen Quoc; Anh, Do Quang; Tuyen, Luc Nguyen; Khoa, Dao Bach; Thai, Cao Quang; Triet, Dao Minh; Phu, Nguyen Hoan; Dunstan, Sarah; Peto, Tim; Clegg, John; Farrar, Jeremy; Weatherall, David

    2010-08-01

    In order to obtain an approximate assessment of the public health burden that will be posed by the inherited disorders of haemoglobin in southern Vietnam, several thousand individuals were screened for these conditions. A smaller sample was screened for glucose-6-phosphate dehydrogenase (G6PD) deficiency. The important haemoglobin disorders identified were beta thalassaemia, haemoglobin E and a variety of different forms of alpha thalassaemia. There were sufficient G6PD-deficient individuals to materially affect malaria control programme design. The most remarkable finding was wide variation in the gene frequencies of these conditions among the ethnic groups sampled. The approximate number of babies expected to be born with clinically significant haemoglobin disorders in Vietnam was estimated from the gene-frequency data. This study emphasizes the importance of wide-scale population screening, including ethnic subgroups, to establish the requirements for inherited haemoglobin disorder programmes in resource-limited settings.

  13. Mantle Flow Implications across Easter and Southern Africa from Shear Wave Splitting Measurements

    NASA Astrophysics Data System (ADS)

    Ramirez, C.; Nyblade, A.; Bagley, B. C.; Mulibo, G. D.; Tugume, F.; Wysession, M. E.; Wiens, D.; van der Meijde, M.

    2015-12-01

    In this study, we present new shear wave splitting results from broadband seismic stations in Botswana and Namibia, and combine them with previous results from stations in Kenya, Uganda, Tanzania, Malawi, Zambia, South Africa, Mozambique, Zimbabwe, and Angola to further examine the pattern of seismic anisotropy across southern Africa. The new results come from stations in northern Namibia and Botswana, which help to fill in large gaps in data coverage. Our preliminary results show that fast polarization directions overall trend in a NE orientation. The most noticeable measurements that deviate from this pattern are located around the Archean Tanzania Craton in eastern Africa. The general NE pattern of fast polarization directions is attributed to mantle flow linked to the African superplume. Smaller scale variations from this general direction can be explained by shape anisotropy in the lithosphere in magmatic regions in the East African rift system and to fossil anisotropy in the Precambrian lithosphere.

  14. Heat flow anomaly in Lesotho - implications for the southern boundary of the Kaapvaal craton

    SciTech Connect

    Jones, M.Q.W. )

    1992-10-01

    Heat flow studies in southern Africa reveal a pattern of low heat flow in Archean cratons compared with Proterozoic mobile belts that provides grounds for modeling in which cratons have lower mantle heat flux and greater lithospheric thickness. Measurements at nine locations in a 90-km-long north-south traverse show an increase of heat flow from typically cratonic values of about 45 mW/sq m in the north to about 80 mW/sq m where the craton abuts on the Natal belt in the south. The change occurs within 30 km, suggesting that the anomaly largely reflects an increase in radioactive heat from the upper crust in the orogenic front. The change in mantle heat flux across the boundary is probably considerably smaller. These and other results suggest that the surficial craton boundary is further north than usually depicted. 20 refs.

  15. Three-dimensional P and S wave velocity structures of southern Peru and their tectonic implications

    NASA Technical Reports Server (NTRS)

    Cunningham, Paul S.; Roecker, Steven W.; Hatzfeld, Denis

    1986-01-01

    Arrival times of compressional and shear (S) waves from microearthquakes recorded in 1981 by an 18-station regional array are used to study the three-dimensional velocity structure of the crust and upper mantle of the central Andes. The data suggest a crustal thickness of about 40 km beneath the coast, increasing to about 70 km beneath the Cordillera Occidental. The inverse correlation between the dip in the Moho and the dip of the slab may indicate a broad-scale causal relation between the two. S wave velocities in the mantle between 70 and 130 km depth above the 30-degree dipping slab are low, possibly indicating the presence of a partially melted asthenosphere that may be responsible for the magmatic activity recorded in southern Peru.

  16. Footprints of large theropod dinosaurs and implications on the age of Triassic biotas from Southern Brazil

    NASA Astrophysics Data System (ADS)

    da Silva, Rafael Costa; Barboni, Ronaldo; Dutra, Tânia; Godoy, Michel Marques; Binotto, Raquel Barros

    2012-11-01

    Dinosaur footprints found in an outcrop of the Caturrita Formation (Rio Grande do Sul State, Southern Brazil), associated with a diverse and well preserved record of fauna and flora, reopen the debate about its exclusive Triassic age. The studied footprints were identified as Eubrontes isp. and are interpreted as having been produced by large theropod dinosaurs. The morphological characteristics and dimensions of the footprints are more derived than those commonly found in the Carnian-Norian, and are more consistent with those found during the Rhaetian-Jurassic. The trackmaker does not correspond to any type of dinosaur yet known from Triassic rocks of Brazil. Recent studies with the paleofloristic content of this unit also support a more advanced Rhaetian or even Jurassic age for this unit.

  17. Geochemical Characterization of Dust in the Southern Ocean, Provenance and Paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Recasens, C.; Goldstein, S. L.; Winckler, G.; Kaplan, M. R.; Gili, S.; Gaiero, D. M.; Anderson, R. F.

    2013-12-01

    Wind-blown dust can be used to trace past and present atmospheric circulation patterns, through the study of its geographical provenance, its spatial distribution and temporal variability. Antarctic and marine records indicate that Patagonia has been a principal source of dust for the southern latitudes, particularly during glacial times. To improve our understanding of dust provenance and transport mechanisms downstream from South America and part-way to Antarctica, we analyzed the fine (<5 μm) fraction terrigenous input into the Southern Ocean by studying the 12.76-m piston core TNO57-6, from 3751 m water depth on the Agulhas Ridge in the Southeast Atlantic, north of the present-day position of the Subantarctic Front and South of the Subtropical Convergence Zone. Due to this core's location and depth, and the position of the winds and marine currents, we suggest that the major input of sediment comes from wind-blown dust material originating in South America. To fingerprint better the terrigenous detritus, we measured chemical compositions and Sr-Nd-Pb-He isotope ratios in samples ranging in age from present-day to MIS 6. Additionally we analyzed material from potential dust source areas in different locations in Patagonia to refine their geochemical signatures. Our first results suggest that the glacial and interglacial samples have different provenances, and that the purely Patagonian sources may represent only the glacial end-member of the dust reaching that location. Further analyses at higher time resolution in the marine record will improve understanding of the relationships between the dust arriving at the site with changing climate, and continued study of potential source area samples (including Patagonia and farther North in La Puna and Altiplano) will help define the other end-member in the dust composition, and thus the more active dust sources during interglacial intervals.

  18. Topographyc metrics in the southern sector of the Marche foothills: implication for active tectonic analysis

    NASA Astrophysics Data System (ADS)

    Materazzi, Marco; Aringoli, Domenico; Carducci, Tamara; Cavitolo, Paolo; Farabollini, Piero; Giacopetti, Marco; Pambianchi, Gilberto; Tondi, Emanuele; Troiani, Francesco

    2016-04-01

    Quantitative geomorphic analysis can be provided a useful contribution to the study of recent tectonics. Some parameters, that quantify the channels morphology, as the Stream Length-Gradient (SL) Index (Hack, 1973) and the Steepness (Ks) Index (Flint, 1974), are generally used to detect anomalies on the expected concave-up equilibrium stream-profile, which can result in local abrupt changes in stream gradient (i.e., knickpoints) and/or broad convexities on stream long-profiles extending for tens of kilometres (i.e., knickzones). The main goal of this work is the study of the morphological and morphometrical features in the southern sector of the Marche Region, with the aim to gain new knowledge on the influences of rock resistance and rock uplift on the fluvial and topographic system. The investigated area is situated in central Italy and it extends from the axial zone of the Umbria-Marche Apennines to the Adriatic Sea, including the southern sector of the Marche Region and belongs to the foredeep domain of the Apennines orogenic system, which has affected by tectonic activity up to very recent times. The rheology of outcropping deposits doesn't allow the strain to be easily recorded at the outcrop scale. The analyses have been aimed at to test the sensitivity of both SL and Ks for evaluating active crustal deformations, acting at different wavelengths on land surface, within a low tectonically active thrust-and-fold belt. Additional purpose was the understanding of the pattern of regional differential crustal activity in the topographic arrangement of the study area In this research project two sets of analysis were conducted. References Hack J.T. 1973. Stream-profile analysis and stream-gradient index. Journal of Research of the U.S. Geological Survey, 1, 421-429. Flint J.J. 1974. Stream gradient as a function of order, magnitude and discharge. Water Resources Research, 10, 969-973.

  19. Implications of magmatic records for Neotethyan subduction beneath the Eurasian margin (Lhasa terrane, southern Tibet)

    NASA Astrophysics Data System (ADS)

    Tan, Jieqing; Aitchison, Jonathan

    2014-05-01

    Evidence for magmatism is widely developed in the Lhasa terrane of southern Tibet. Much of this is related to northward subduction of the Neotethyan Ocean prior the India-Eurasia collision. To better understand the tectono-magmatism, we systematically studied the published data for Middle Jurassic-Eocene igneous rocks in southern Tibet. Many of these rocks formed during two important intervals from ca. 110-80 Ma and ca. 65-40 Ma. On the basis of the reported rocks in this area, we considered the possibility that a Neotethyan mid-ocean ridge was subducted during the early peak episode (ca. 110-80 Ma). With this ridge subduction system, hot asthenosphere rose up through a slab window causing both oceanic slab and mantle wedge melting that resulted in peak volcanism during the Late Cretaceous. As young and hot crust at a mid-ocean ridge has a relatively low density, and thus potentially positive buoyancy, the subduction of a buoyant mid-ocean ridge may have led to a reduction in the angle of subduction. Evidence for termination of arc magmatism by the flat subducted oceanic slab is recorded by a magmatic gap ca. 80-65 Ma. Around ca. 65 Ma, the magmatic record appears again accompanied by a southward migration that represents resumption of an oceanic slab subduction at a normal subduction angle. Subsequently, magmatism lasts to ca. 36 Ma before the India-Eurasia collision and reached a peak of activity associated with a magmatic flare-up at 50 Ma. In this subduction system, some magmatic processes triggered formation of porphyry ore deposits and affected the temporal and spatial distribution of ores.

  20. The Variscan belt of Northern France Southern Belgium: geodynamic implications of new palaeomagnetic data

    NASA Astrophysics Data System (ADS)

    Márton, Emő; Mansy, Jean-Louis; Averbuch, Olivier; Csontos, László

    2000-09-01

    Palaeomagnetic investigations were carried out in Devonian-early Carboniferous rocks of the Variscan foreland chain of Northern France-Southern Belgium in order to reveal the origin of its arcuate shape. The Brabant Parautochthon was sampled in the Boulonnais (near Calais) and near Tournai, while the Ardenne Allochthon was sampled near Maubeuge and in the Givet area. All the sampled localities yielded characteristic remanent magnetization as a result of stepwise demagnetization and component analysis. Fold or tilt tests were possible for three localities, with negative results indicating pervasive remagnetization. The tectonic position was sub-horizontal at two localities, while the tilt was monoclinal for the rest. Therefore, the acquisition time of the magnetic signals was estimated by comparing the palaeolatitude computed from each magnetic component to the palaeolatitudes of Variscan Europe calculated after Van der Voo (1993). Three components showing: A, a southern B, a near-Equatorial, and C, a northern palaeolatitude are recognized from our data. Since a pre-Variscan age of component A (observed only in Boulonnais, at 10 sites) is not supported by data, it is assigned to an early phase of deformation. Component B (16 sites) was acquired during the peak of the Variscan tectonics (late Westphalian), while component C (five sites) originated during Permian times. Regardless of the palaeolatitudes, declinations fall between 190 and 210°, thus being conformable with the declinations expected for Variscan Europe. The declinations show no correlation with the arcuate shape of the belt, neither are they different in the Paraauthochthon and in the Allochthon, nor in the different components. Arc formation by moulding of the Allochthon on the Brabant Parautochthon is, therefore, not supported by these data, since this mechanism requires substantial (opposed) rotations on both wings of the arc. The available palaeomagnetic data are conformable with a pre-formed arc

  1. Recent Rifting Events in the Southern Red Sea and Regional Implications

    NASA Astrophysics Data System (ADS)

    Ruch, J.; Xu, W.; Jonsson, S.

    2014-12-01

    During the last decades, several rifting events on land have been observed along divergent plate boundaries, separating plates up to several meters in a few weeks. These events are typically accompanied by short-term seismic swarms (<15 days) and normal faulting, and are in some cases followed by eruptions as well. These on land rifting events represent, however, a very limited portion (< 2%) of global intrusions that take place in most cases along mid-ocean ridge systems. Here we focus on the southern Red Sea area, which is a part of the triple junction separating the Nubian, Somalian and Arabian plates where several earthquake swarms were recorded from 2000 to 2014. In three cases, these swarms were followed by eruptions within a year, at Jebel at Tair (2007) and in the Zubair Archipelago (40 km south) were two new volcanic islands developed in 2011 and 2013. Without the surface eruptions, these intrusive events may have remained unnoticed. Together the surface evidence of volcanic activity and recorded seismic swarms during the past two decades allow for a better definition of the overall magmatic activity in the southern Red Sea. We further discuss the possibility that Zubair, which is an emerged portion of a shallow 20 km-long by 5 km-wide NNW-SSE oriented platform, may be the surface expression of an active spreading center, comparable in size with other on land spreading centers. The recent concentration of activity at Zubair developed in a context of high regional magmatic and tectonic activity, including the rifting episode at Dabbahu (2005-2011), the rifting event in the Gulf of Aden (2010-2011) and the 2011 Nabro volcano eruption. Preliminary analysis of regional structural features and volcano lineaments suggest distinct intrusion paths and faulting running parallel to the three main active rift zone axes, and also along a dominant NE-SW oriented preexisting regional fault zones affecting the entire triple junction area.

  2. Identifying potential sources of Sudan I contamination in Capsicum fruits over its growth period.

    PubMed

    Wu, Naiying; Gao, Wei; Zhou, Li; Lian, Yunhe; Li, Fengfei; Han, Wenjie

    2015-04-15

    Sudan dyes in spices are often assumed to arise from cross-contamination or malicious addition. Here, experiments were carried out to identify the potential source of Sudan I-IV in Capsicum fruits through investigation of their contents in native Capsicum tissues, soils and associated agronomic materials. Sudan II-IV was not detected in any of the tested samples. Sudan I was found in almost all samples except for the mulching film. Sudan I concentrations decreased from stems to leaves and then to fruits or roots. Sudan I levels in soils were significantly elevated by vegetation treatment. These results exclude the possibility of soil as the main source for Sudan I contamination in Capsicum fruits. Further study found out pesticide and fertilizer constitutes the major source of Sudan I contamination. This work represents a preliminary step for a detailed Sudan I assessment to support Capsicum management and protection in the studied region.

  3. Ecological implications of Laurel Wilt infestation on Everglades Tree Islands, southern Florida

    USGS Publications Warehouse

    Snyder, James R.

    2014-01-01

    , laurel wilt disease also kills other native trees that are members of the laurel family, including swamp bay (Persea palustris), silk bay (Persea borbonia var. humilis), and sassafras (Sassafras albidum), as well as the economically important cultivated avocado (Persea americana) (Fraedrich and others, 2008). This paper is concerned primarily with swamp bay, an important component of Everglades tree islands.The spread of the redbay ambrosia beetle and its fungal symbiont has been very rapid, exceeding model predictions (Koch and Smith, 2008); by 2011, laurel wilt disease was found from the southern coastal plain of North Carolina to southern peninsular Florida. The first redbay ambrosia beetle was trapped in Miami-Dade County in March 2010, and laurel wilt disease was discovered in swamp bays in February 2011 and in commercial avocado groves about a year later (Kendra and others, 2013). By 2013, laurel wilt disease was seen in swamp bays throughout the southern Everglades in Everglades National Park, Big Cypress National Preserve, and Water Conservation Areas (WCAs) 3A and 3B (Rodgers and others, 2014).

  4. Cytogenetics of the Anopheles gambiae complex in Sudan, with special reference to An. arabiensis: relationships with East and West African populations.

    PubMed

    Petrarca, V; Nugud, A D; Ahmed, M A; Haridi, A M; Di Deco, M A; Coluzzi, M

    2000-06-01

    The species composition of malaria vector mosquitoes belonging to the Anopheles gambiae complex (Diptera: Culicidae) from >40 localities in Sudan, representing most ecological situations, was determined by analysis of ovarian polytene chromosomes. Of 2162 females, 93% were identified as An. arabiensis Patton and 7% were An. gambiae Giles sensu stricto. No hybrids were found between the two species. Anopheles arabiensis occurred in all but two sites, whereas An. gambiae s.s. was effectively limited to the southernmost, more humid localities. For chromosomal paracentric inversions, the degree of polymorphism was low in An. gambiae s.s. (inversions 2La, 2Rb and 2Rd), higher in An. arabiensis (inversions Xe, 2Ra, b, bc, d1, s; 3Ra, d). Anopheles gambiae samples from Sudan were all apparently panmictic, i.e. they did not show restricted gene flow such as observed among West African populations (interpreted as incipient speciation). Chromosomal inversion patterns of An. gambiae in southern Sudan showed characteristics of intergrading Savanna/Forest populations similar to those observed in comparable eco-climatic situations of West Africa. Anopheles arabiensis was polymorphic for inversion systems recorded in West Africa (2Ra, 2Rb, 2Rdl, 3Ra) and for a novel 2Rs polymorphism, overlapping with inversion systems 2Rb and 2Rd1. Samples carrying the 2Rs inversion were mostly from Khashm-el-Girba area in central-eastern Sudan. In the great majority of the samples all polymorphic inversions were found to be in Hardy-Weinberg equilibrium. Sudan populations of An. arabiensis should therefore be considered as generally panmictic. Anopheles arabiensis shows more inversion polymorphism in west than in east African populations. Sudan populations have more evident similarities with those from westwards than those from eastwards of the Great Rift Valley. The possible influence of the Rift on evolution of An. arabiensis is discussed.

  5. Modeling Fire Emissions across Central and Southern Italy: Implications for Land and Fire Management

    NASA Astrophysics Data System (ADS)

    Bacciu, V. M.; Salis, M.; Spano, D.

    2015-12-01

    Fires play a relevant role in the global and regional carbon cycle, representing a remarkable source of CO2 and other greenhouse gases (GHG) that influence atmosphere budgets and climate. In addition, the wildfire increase projected in Southern Europe due to climate change (CC) and concurrent exacerbation of extreme weather conditions could also lead to a significant rise in GHG. Recently, in the context of the Italian National Adaptation Strategy to Climate Change (SNAC), several approaches were identified as valuable tools to adapt and mitigate the impacts of CC on wildfires, in order to reduce landscape susceptibility and to contribute to the efforts of carbon emission mitigation proposed within the Kyoto protocol. Active forest and fuel management (such as prescribed burning, fuel reduction and removal, weed and flammable shrub control, creation of fuel discontinuity) is recognised to be a key element to adapt and mitigate the impacts of CC on wildfires. Despite this, overall there is a lack of studies about the effectiveness of fire emission mitigation strategies. The current work aims to analyse the potential of a combination of fuel management practices in mitigating emissions from forest fires and evaluate valuable and viable options across Central and Southern Italy. These objectives were achieved throughout a retrospective application of an integrated approach combining a fire emission model (FOFEM - First Order Fire Effect Model) with spatially explicit, comprehensive, and accurate fire, vegetation and weather data for the period 2004-2012. Furthermore, a number of silvicultural techniques were combined to develop several fuel management scenarios and then tested to evaluate their potential in mitigating fire emissions.The preliminary results showed the crucial role of appropriate fuel, fire behavior, and weather data to reduce bias in quantifying the source and the composition of fire emissions and to attain reasonable estimations. Also, the current

  6. The 2013 severe haze over the southern Hebei, China: model evaluation, source apportionment, and policy implications

    NASA Astrophysics Data System (ADS)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2013-11-01

    Extremely severe and persistent haze occurred in January 2013 over the eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, seven of the top ten polluted cities in China were within Hebei Province. The three cities in southern Hebei, Shijiazhuang, Xingtai, and Handan, have been listed as the top three polluted cities according to the statistics for the first half year of 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and the northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory of China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most-polluted cities in southern Hebei are quantified aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely severe polluted episodes. The MEIC inventory is proved to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from the northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, comparing with those from Shanxi and the northern Hebei for December 2007. For Xingtai and

  7. The 2013 severe haze over southern Hebei, China: model evaluation, source apportionment, and policy implications

    NASA Astrophysics Data System (ADS)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2014-03-01

    Extremely severe and persistent haze occurred in January 2013 over eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, 7 of the top 10 polluted cities in China were within the Hebei Province. The three cities in southern Hebei (Shijiazhuang, Xingtai, and Handan) have been listed as the top three polluted cities according to the statistics for the first half of the year 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory for China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most polluted cities in southern Hebei are quantified by aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in the period 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely polluted episodes. The MEIC inventory is proven to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, compared with those from Shanxi and northern Hebei for December 2007. For Xingtai and Handan

  8. Obstacles to health care: a nurse's experience in Sudan.

    PubMed

    Klaassen, Whitney C

    2007-10-01

    Sudan is a country known for its long history of wars, poverty, and disease. These factors combine to cause a high incidence of morbidity and mortality and the inability of the population to seek and receive medical care.

  9. Clinical and Pharmacogenomic Implications of Genetic Variation in a Southern Ethiopian Population

    PubMed Central

    Tekola-Ayele, Fasil; Adeyemo, Adebowale; Aseffa, Abraham; Hailu, Elena; Finan, Chris; Davey, Gail

    2014-01-01

    Africa is home to genetically diverse human populations. We compared the genetic structure of the Wolaita ethnic population from southern Ethiopia (WETH, n=120) with HapMap populations using genome-wide variants. We investigated allele frequencies of 443 clinically and pharmacogenomically relevant genetic variants in WETH compared to HapMap populations. We found that WETH were genetically most similar to the Kenya Maasai and least similar to the Japanese in HapMap. Variant alleles associated with increased risk of adverse reactions to drugs used for treating tuberculosis (rs1799929 and rs1495741 in NAT2), thromboembolism (rs7294, rs9923231 and rs9934438 in VKORC1), and HIV/AIDS and solid tumors (rs2242046 in SLC28A1) had significantly higher frequencies in WETH compared to African ancestry HapMap populations. Our results illustrate that clinically relevant pharmacogenomic loci display allele frequency differences among African populations. We conclude that drug dosage guidelines for important global health diseases should be validated in genetically diverse African populations. PMID:25069476

  10. River channel adjustments in Southern Italy over the past 150 years and implications for channel recovery

    NASA Astrophysics Data System (ADS)

    Scorpio, Vittoria; Aucelli, Pietro P. C.; Giano, Salvatore I.; Pisano, Luca; Robustelli, Gaetano; Rosskopf, Carmen M.; Schiattarella, Marcello

    2015-12-01

    Multi-temporal GIS analysis of topographic maps and aerial photographs along with topographic and geomorphological surveys are used to assess evolutionary trends and key control factors of channel adjustments for five major rivers in southern Italy (the Trigno, Biferno, Volturno, Sinni and Crati rivers) to support assessment of channel recovery and river restoration. Three distinct phases of channel adjustment are identified over the past 150 years primarily driven by human disturbances. Firstly, slight channel widening dominated from the last decades of the nineteenth century to the 1950s. Secondly, from the 1950s to the end of the 1990s, altered sediment fluxes induced by in-channel mining and channel works brought about moderate to very intense incision (up to 6-7 m) accompanied by strong channel narrowing (up to 96%) and changes in channel configuration from multi-threaded to single-threaded patterns. Thirdly, the period from around 2000 to 2015 has been characterized by channel stabilization and local widening. Evolutionary trajectories of the rivers studied are quite similar to those reconstructed for other Italian rivers, particularly regarding the second phase of channel adjustments and ongoing transitions towards channel recovery in some reaches. Analyses of river dynamics, recovery potential and connectivity with sediment sources of the study reaches, framed in their catchment context, can be used as part of a wider interdisciplinary approach that views effective river restoration alongside sustainable and risk-reduced river management.

  11. Arsenic contamination and potential health risk implications at an abandoned tungsten mine, southern China.

    PubMed

    Liu, Chuan-ping; Luo, Chun-ling; Gao, Yun; Li, Fang-bai; Lin, Lan-wen; Wu, Chang-an; Li, Xiang-dong

    2010-03-01

    In an extensive environmental study, field samples, including soil, water, rice, vegetable, fish, human hair and urine, were collected at an abandoned tungsten mine in Shantou City, southern China. Results showed that arsenic (As) concentration in agricultural soils ranged from 3.5 to 935 mg kg(-1) with the mean value of 129 mg kg(-1). In addition, As concentration reached up to 325 microg L(-1) in the groundwater, and the maximum As concentration in local food were 1.09, 2.38 and 0.60 mg kg(-1) for brown rice, vegetable and fish samples, respectively, suggesting the local water resource and food have been severely contaminated with As. Health impact monitoring data revealed that As concentrations in hair and urine samples were up to 2.92 mg kg(-1) and 164 microg L(-1), respectively, indicating a potential health risk among the local residents. Effective measurements should be implemented to protect the local community from the As contamination in the environment.

  12. Arsenic contamination and potential health risk implications at an abandoned tungsten mine, southern China.

    PubMed

    Liu, Chuan-ping; Luo, Chun-ling; Gao, Yun; Li, Fang-bai; Lin, Lan-wen; Wu, Chang-an; Li, Xiang-dong

    2010-03-01

    In an extensive environmental study, field samples, including soil, water, rice, vegetable, fish, human hair and urine, were collected at an abandoned tungsten mine in Shantou City, southern China. Results showed that arsenic (As) concentration in agricultural soils ranged from 3.5 to 935 mg kg(-1) with the mean value of 129 mg kg(-1). In addition, As concentration reached up to 325 microg L(-1) in the groundwater, and the maximum As concentration in local food were 1.09, 2.38 and 0.60 mg kg(-1) for brown rice, vegetable and fish samples, respectively, suggesting the local water resource and food have been severely contaminated with As. Health impact monitoring data revealed that As concentrations in hair and urine samples were up to 2.92 mg kg(-1) and 164 microg L(-1), respectively, indicating a potential health risk among the local residents. Effective measurements should be implemented to protect the local community from the As contamination in the environment. PMID:19910093

  13. Environmental and Archaeological Implications of a Late Quaternary Palynological Sequence, Poyang Lake, Southern China

    NASA Astrophysics Data System (ADS)

    Jiang, Qinhua; Piperno, Dolores R.

    1999-09-01

    Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous-evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys.

  14. Snow-avalanche impact landforms in Breheimen, southern Norway: Origin, age, and paleoclimatic implications

    SciTech Connect

    Matthews, J.A.; McCarroll, D. )

    1994-05-01

    Twelve snow-avalanche ramparts in Jostedalen and Sprongdalen (Breheimen, southern Norway) are investigated to elucidate processes of formation, the history of avalanche activity, and their potential for paleoclimatic reconstruction. Variation in the form of these riverbank boulder ramparts reflects local patterns of avalanche impact. Differences in clast roundness between ramparts, avalanche tracks, and river beds indicate that, on average, 50 to 60% of the clasts in the ramparts originate from river bedload as opposed to avalanche source areas or tracks. Rampart clasts increase in roundness downstream over a distance of 12 km, and the contribution from the river bed varies from 26 to 80% depending on local factors. Conventional lichenometric dating suggests ages for the initiation of rampart formation of 250 to 2000 yr, but they probably have a much longer history. Lichen-size frequency distributions, using the largest lichen from each of n boulders, reflect the age-frequency of surface boulders, providing a record of late Holocene avalanche activity. A simulation model suggests that maximum avalanche activity affected nine of the ramparts during the 19th century, after the peak of the Little Ice Age. The pattern of avalanche activity differs from the pattern of glacier variations but is in close agreement with that of debris-flow activity. The ramparts may yield a valuable proxy record of winter snowfall. 48 refs., 12 figs., 4 tabs.

  15. Folklore and traditional ecological knowledge of geckos in Southern Portugal: implications for conservation and science

    PubMed Central

    2011-01-01

    Traditional Ecological Knowledge (TEK) and folklore are repositories of large amounts of information about the natural world. Ideas, perceptions and empirical data held by human communities regarding local species are important sources which enable new scientific discoveries to be made, as well as offering the potential to solve a number of conservation problems. We documented the gecko-related folklore and TEK of the people of southern Portugal, with the particular aim of understanding the main ideas relating to gecko biology and ecology. Our results suggest that local knowledge of gecko ecology and biology is both accurate and relevant. As a result of information provided by local inhabitants, knowledge of the current geographic distribution of Hemidactylus turcicus was expanded, with its presence reported in nine new locations. It was also discovered that locals still have some misconceptions of geckos as poisonous and carriers of dermatological diseases. The presence of these ideas has led the population to a fear of and aversion to geckos, resulting in direct persecution being one of the major conservation problems facing these animals. It is essential, from both a scientific and conservationist perspective, to understand the knowledge and perceptions that people have towards the animals, since, only then, may hitherto unrecognized pertinent information and conservation problems be detected and resolved. PMID:21892925

  16. Shear-wave splitting beneath southern Korea and its tectonic implication

    NASA Astrophysics Data System (ADS)

    Kang, Tae-Seob; Shin, Jin Soo

    2009-06-01

    Seismic anisotropy beneath the southern Korean Peninsula (SKP) was investigated based on the ScS waves of deep-focused earthquakes recorded at 35 broadband stations. The most striking feature of the observed splitting patterns is the preference of the fast directions (NW-SE) that are nearly parallel to the direction of the absolute plate motion in the region. However, the splitting patterns over the region show significant variation in splitting parameters indicating a complex anisotropic structure. Variations of the splitting directions and dissimilarity in the source domains of basaltic volcanisms suggest that the asthenospheric mantle flow since at least the late Cenozoic cannot explain the seismic anisotropy beneath the region. Comparison to shear-wave splitting measurements from eastern China revealed that the NW-SE fast direction of splitting measurements in the SKP is close to that in the North China block (NCB) while the NE-SW fast direction might be related to that in the South China block (SCB). The shallow mantle lithosphere beneath the SKP retains the fossil anisotropy amalgamated prior to the late Paleozoic before the collision between the NCB and SCB, and the anisotropic structure was not completely realigned by the major orogenic events during the late Paleozoic to Mesozoic eras.

  17. Folklore and traditional ecological knowledge of geckos in Southern Portugal: implications for conservation and science.

    PubMed

    Ceríaco, Luis M P; Marques, Mariana P; Madeira, Natália C; Vila-Viçosa, Carlos M; Mendes, Paula

    2011-09-05

    Traditional Ecological Knowledge (TEK) and folklore are repositories of large amounts of information about the natural world. Ideas, perceptions and empirical data held by human communities regarding local species are important sources which enable new scientific discoveries to be made, as well as offering the potential to solve a number of conservation problems. We documented the gecko-related folklore and TEK of the people of southern Portugal, with the particular aim of understanding the main ideas relating to gecko biology and ecology. Our results suggest that local knowledge of gecko ecology and biology is both accurate and relevant. As a result of information provided by local inhabitants, knowledge of the current geographic distribution of Hemidactylus turcicus was expanded, with its presence reported in nine new locations. It was also discovered that locals still have some misconceptions of geckos as poisonous and carriers of dermatological diseases. The presence of these ideas has led the population to a fear of and aversion to geckos, resulting in direct persecution being one of the major conservation problems facing these animals. It is essential, from both a scientific and conservationist perspective, to understand the knowledge and perceptions that people have towards the animals, since, only then, may hitherto unrecognized pertinent information and conservation problems be detected and resolved.

  18. Appearance of De Geer moraines in southern and western Finland - Implications for reconstructing glacier retreat dynamics

    NASA Astrophysics Data System (ADS)

    Ojala, Antti E. K.

    2016-02-01

    LiDAR digital elevation models (DEMs) from southern and western Finland were investigated to map and discriminate features of De Geer moraines, sparser and more scattered end moraines, and larger end moraine features (i.e., ice-marginal complexes). The results indicate that the occurrence and distribution of De Geer moraines and scattered end moraine ridges in Finland are more widespread than previously suggested. This is probably attributed to the ease of detecting and mapping these features with high-resolution DEMs, indicating the efficiency of LiDAR applications in geological and geomorphological studies. The variable appearance and distribution of moraine ridges in Finland support previous interpretations that no single model is likely to be appropriate for the genesis of De Geer moraines at all localities and for all types of end moraines. De Geer moraine appearances and interdistances probably result from a combination of the general rapidity of ice-margin recession during deglaciation, the proglacial water depth in which they were formed, and local glacier dynamics related to climate and terrain topography. The correlation between the varved clay-based rate of deglaciation and interdistances of distinct and regularly spaced De Geer moraine ridges indicates that the rate of deglaciation is probably involved in the De Geer ridge-forming process, but more thorough comparisons are needed to understand the extent to which De Geer interdistances represent an annual rate of ice-margin decay and the rapidity of regional deglaciation.

  19. A New Oviraptorosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleoecological Implications

    PubMed Central

    Lü, Junchang; Yi, Laiping; Zhong, Hui; Wei, Xuefang

    2013-01-01

    A new oviraptorosaur Nankangia jiangxiensis gen. et sp. nov. is described on the basis of a partial postcranial skeleton with a partial lower jaw collected from the Upper Cretaceous Nanxiong Formation of Ganzhou, in Jiangxi Province of southern China. The new taxon is diagnosed by: (1) a mandibular symphysis that is not turned down; (2) neural spines of the cranial caudal vertebrae that are wider transversely than anteroposteriorly, forming a large posterior fossa with rugose central areas; (3) a femoral neck extending at an angle of about 90 to the shaft; and (4) a ratio of femur to tibia length of 0.95. Phylogenetic analysis recovers Nankangia as basal to the oviraptorid Yulong, but more derived than Caenagnathus, which also has a mandibular symphysis that is not turned down. The coexistence of Nankangia jiangxiensis, Ganzhousaurus nankangensis, Jiangxisaurus ganzhouensis, an unnamed oviraptorid from Nanxiong Basin and Banji long suggests that they occupied distinct ecological niches. Nankangia may have been more herbivorous than carnivorous. PMID:24312233

  20. Tephrochronology of a 72 ka-long marine record: implications for the southern Tyrrhenian explosive volcanism

    NASA Astrophysics Data System (ADS)

    Tamburrino, Stella; Insinga, Donatella; Pelosi, Nicola; Kissel, Catherine; Laj, Carlo; Capotondi, Lucilla; Sprovieri, Mario

    2015-04-01

    Several discrete tephra layers occur in a Marion Dufresne 13.9 m-long deep-sea core (MD01-2474G) from the southern Tyrrhenian Sea. Major, minor and trace element data (EMPA-WDS and LA-ICP-MS analyses) from fresh micro-pumices and glass shards allow to correlate them with the volcanic activity from Aeolian Islands (Lipari, Vulcano, Salina), Campanian Plain (Ischia), Pantelleria and Mt. Etna. The chronology of the succession is provided by a high-resolution age-model based on isotope stratigraphy and AMS radiocarbon dating, which places the succession in a time interval spanning the last 72 kyrs BP. According to a detailed proximal-distal and distal-distal correlation, a precise chronological framework is established and some main markers tephras of the central Mediterranean area (Y-1, Y-6, Y-7 and Y-8) are recognised. In additions, the succession is a precious archive to record multiple volcanic events occurred at Ischia volcano and the Aeolian Arc (Lipari and Vulcano). This latter, in particular, erupted several products which exhibits strong compositional variations otherwise non detectable from terrestrial counterparts. The results of the present study, hence, provide new data for a detailed analytical reference database of the Tyrrhenian Sea tephrochronology and may contribute to a better chronostratigraphic reconstruction of the Aeolian arc explosive events.

  1. Application of Raman spectroscopy technology to studying Sudan I

    NASA Astrophysics Data System (ADS)

    Li, Gang; Zhang, Guoping; Chen, Chen

    2006-06-01

    Being an industrial dye, the Sudan I may have a toxic effect after oral intake on the body, and has recently been shown to cause cancer in rats, mice and rabbits. Because China and some other countries have detected the Sudan I in samples of the hot chilli powder and the chilli products, it is necessary to study the characteristics of this dye. As one kind of molecule scattering spectroscopy, Raman spectroscopy is characterized by the frequency excursion caused by interactions of molecules and photons. The frequency excursion reflects the margin between certain two vibrational or rotational energy states, and shows the information of the molecule. Because Raman spectroscopy can provides quick, easy, reproducible, and non-destructive analysis, both qualitative and quantitative, with no sample preparation required, Raman spectroscopy has been a particularly promising technique for analyzing the characteristics and structures of molecules, especially organic ones. Now, it has a broad application in biological, chemical, environmental and industrial applications. This paper firstly introduces Sudan I dye and the Raman spectroscopy technology, and then describes its application to the Sudan I. Secondly, the fingerprint spectra of the Sudan I are respectively assigned and analyzed in detail. Finally, the conclusion that the Raman spectroscopy technology is a powerful tool to determine the Sudan I is drawn.

  2. Landscape formation at the Deuteronilus contact in southern Isidis Planitia, Mars: Implications for an Isidis Sea?

    NASA Astrophysics Data System (ADS)

    Erkeling, G.; Reiss, D.; Hiesinger, H.; Ivanov, M. A.; Hauber, E.; Bernhardt, H.

    2014-11-01

    Two of the most widely studied landforms that are associated with a putative ocean that filled the northern hemisphere of Mars are (1) the Vastitas Borealis Formation (VBF), plain units that cover a larger portion of the northern lowlands of Mars, and (2) a candidate paleoshoreline, e.g., the Deuteronilus contact, which represents the outer margin of the VBF. The VBF and the Deuteronilus contact are interpreted to result from a short-lived Late Hesperian ocean that readily froze and sublimated. Similar landforms are also present in the impact basin of Isidis Planitia and suggest formation processes comparable to those that formed the VBF and the Deuteronilus contact in the northern lowlands. Our study of the Deuteronilus contact in Isidis revealed geologic evidence that possibly supports the existence of a Late Hesperian/Early Amazonian Isidis Sea. For example, numerous valleys that are incised into the plains of the southern Isidis basin rim between 82°/90°E and 3°/6°N and trend a few tens of kilometers to the north following the general topographic gradient toward the center of Isidis Planitia. A few of them reach the Deuteronilus contact and continue as sinuous ridges in the Isidis Interior Plains (IIP). Based on our findings we conclude that the geologic setting along the Deuteronilus contact, including the valleys and ridges is a result of (1) Late Hesperian short-term fluvial activity, (2) a Late Hesperian/Early Amazonian short-lived Isidis Sea that readily froze, (3) subglacial drainage and esker formation, and (4) subsequent sublimation of the proposed Isidis ice sheet. Although the fluvio-glacial model we introduce in our manuscript cannot fully explain the geologic setting, possible alternative formation models, including relief inversion and fluvio-volcanic scenarios are even less capable in explaining the observed geologic setting along the Deuteronilus contact.

  3. Variability of the Southern California wave climate and implications for sediment transport

    USGS Publications Warehouse

    Xu, J. P.; Noble, M.A.

    2009-01-01

    We analyzed wave and wind data from 18 buoys in the Southern California Bight to characterize the spatial and temporal variability of the regional wave climate. Point Conception shelters most of the Bight from being directly impacted by North Pacific weather. The wave height inside the sheltered zone and to the east of the Channel Islands is less than half the wave height in the open ocean to the west. Within the sheltered Bight, storm waves (by proxy of being greater than the 95th percentile wave height for more than 6 hours) are mainly from the west, but long period swells (Tp >15 seconds) are mainly from the south-southwest. There are on average two to four storms during each winter month (November-March) and fewer than two storms per month for the rest of the year. The Channel Islands selectively block the westerly swells and make the wave climate in the Santa Barbara Channel different from the rest of the sheltered Bight. A statistically significant wave-height minimum exists in the area offshore Dana Point and Oceanside. The multiyear (2-23 years) wave-data records from all 18 buoys show negligible temporal trend, positive or negative. Like the wave climate, the long-term probability of sediment transport on the continental shelves of the Bight displays large difference between the sheltered and open-ocean (near Point Conception) sites. The return period of incipient sediment motion on the sheltered shelf breaks (one to five months) is at least two orders of magnitude longer than that on the Point Conception shelf break (0.6 day). Similar to the spatial distribution of wave heights, there is a systematic return-period maximum on the shelf off Dana Point and Oceanside. ?? 2009 The Geological Society of America.

  4. Stratigraphy of the Younger Dryas Chronozone and paleoenvironmental implications: Central and Southern Great Plains

    USGS Publications Warehouse

    Holliday, V.T.; Meltzer, D.J.; Mandel, R.

    2011-01-01

    The Great Plains of the United States was the setting for some of the earliest research in North America into patterns and changes in the character of late Pleistocene environments and their effects on contemporary human populations. Many localities in the region have well-stratified records of terminal Pleistocene and early Holocene human (Paleoindian) activity and past environments. These have proven important in debates over the character of the Younger Dryas Chronozone (YDC; 11,000-10,000 14C BP; 12,900-11,700 cal BP) in the continental interior. This paper reviews the lithostratigraphic record of the YDC on the Central and Southern Great Plains and summarizes paleobiological records (largely isotopic). The goal is to determine if there is any uniformity in the timing, character, direction and/or magnitude of changes in depositional environments or broader geomorphic systems before, during or after the YDC in order to address the question of the character of environments through this time. The stratigraphic records of the late Pleistocene to early Holocene transition, and in particular, the stratigraphic records of the YDC vary through time and space. The data clearly show that a host of geomorphic processes produced the terminal Pleistocene and early Holocene stratigraphic records of the Great Plains. Moreover, the YDC is not necessarily manifest as a distinct lithostratigraphic or biostratigraphic entity in these different types of deposits and soils. The various geomorphic systems of the Great Plains did not behave synchronously in response to any common climate driver. These stratigraphic records reflect local environmental conditions and probably a complex response to the reorganization of mid-latitude climates in the terminal Pleistocene and early Holocene. ?? 2011 Elsevier Ltd and INQUA.

  5. The Impact of Fire on Energy Balance in Southern African Savanna Ecosystems: Implications of Climate Change

    NASA Astrophysics Data System (ADS)

    Dintwe, K.; Okin, G. S.; Saha, M.; Scanlon, T. M.; D'Odorico, P.; De Sales, F.; Xue, Y.

    2015-12-01

    Savannas are the most fire prone ecosystems in the world accounting for more than 75% of annual global fires. Wildfires in savannas consume large quantities of biomass releasing CO2 and aerosols while leaving ash and char residues. The residues form black-grey patches on the soil surface, and together with newly exposed bare soil patches, they play a significant role in altering surface reflectance and vegetation condition. We investigated the impact of fire on savanna albedo and vegetation greenness (from Enhanced Vegetation Index, EVI) from 2000-2014 using data from the Moderate Resolution Imaging Spectrometer (MODIS) for Africa south of the Equator. Preliminary results indicate that more mesic savannas near the Equator have the highest fire frequencies, with fire frequency generally decreasing with aridity. Immediately after fires, the average change in albedo and EVI is -5% and -10%, respectively, with the magnitude of the change increasing with aridity. The time for albedo to recover to values similar to unburned areas varied by latitude, with more mesic savannas recovering much faster (24 days vs. 65 days for dry savannas). The time for vegetation condition to recover did not vary strongly by latitude (about 65 days). The upward shortwave energy in burnt areas in mesic savannas is 53 W m-2 compared to 95 W m-2 for unburnt areas, indicating a positive forcing of about 42 W m-2 associated with mesic savanna fires locally. Approximately 7% of the (primarily savanna) land in southern Africa burns each year, suggesting an overall forcing in Africa south of the Equator of ~1-2 W m-2 associated with savanna fires. This large forcing indicates clearly the important interplay between ecosystem processes (fire) and climate (radiative forcing) in this region. With changing climate, this region is expected to become significantly drier, suggesting that the forcing due to fire might decrease in the coming decades and indicating that fire-induced albedo changes potentially

  6. The geophysical character of southern Alaska-Implications for crustal evolution

    USGS Publications Warehouse

    Saltus, R.W.; Hudson, T.L.; Wilson, F.H.

    2007-01-01

    The southern Alaska continental margin has undergone a long and complicated history of plate convergence, subduction, accretion, and margin-parallel displacements. The crustal character of this continental margin is discernible through combined analysis of aeromagnetic and gravity data with key constraints from previous seismic interpretation. Regional magnetic data are particularly useful in defining broad geophysical domains. One of these domains, the south Alaska magnetic high, is the focus of this study. It is an intense and continuous magnetic high up to 200 km wide and ∼1500 km long extending from the Canadian border in the Wrangell Mountains west and southwest through Cook Inlet to the Bering Sea shelf. Crustal thickness beneath the south Alaska magnetic high is commonly 40–50 km. Gravity analysis indicates that the south Alaska magnetic high crust is dense. The south Alaska magnetic high spatially coincides with the Peninsular and Wrangellia terranes. The thick, dense, and magnetic character of this domain requires significant amounts of mafic rocks at intermediate to deep crustal levels. In Wrangellia these mafic rocks are likely to have been emplaced during Middle and (or) Late Triassic Nikolai Greenstone volcanism. In the Peninsular terrane, the most extensive period of mafic magmatism now known was associated with the Early Jurassic Talkeetna Formation volcanic arc. Thus the thick, dense, and magnetic character of the south Alaska magnetic high crust apparently developed as the response to mafic magmatism in both extensional (Wrangellia) and subduction-related arc (Peninsular terrane) settings. The south Alaska magnetic high is therefore a composite crustal feature. At least in Wrangellia, the crust was probably of average thickness (30 km) or greater prior to Triassic mafic magmatism. Up to 20 km (40%) of its present thickness may be due to the addition of Triassic mafic magmas. Throughout the south Alaska magnetic high, significant crustal growth

  7. The thermal responses of rock art pigments: Implications for rock art weathering in southern Africa

    NASA Astrophysics Data System (ADS)

    Hall, Kevin; Meiklejohn, Ian; Arocena, Joselito

    2007-10-01

    The San rock art of southern Africa is an international heritage subject to degradation and loss resulting from weathering. The paintings occur within rock shelters, where many are exposed to direct solar radiation for varying periods, rather than occurring in dark caves. As part of a study on the factors thought to be impacting weathering, data were collected pertaining to rock and pigment temperatures as well as humidity within the rock shelters. In addition, XRD analyses were undertaken on pigment samples, and the pigment to rock and pigment to pigment contacts were investigated by means of SEM. Pigments were found to be composed of ferric oxide (the ochre) and a gypsum-clay mix (the white) and to occur as a layer on top of, rather than penetrating into, the sandstone. Noncontact infrared sensors were used to monitor the temperatures of the actual pigments while micro-thermocouples to monitor the surrounding (nonpainted) rock surfaces. Thermal data show that there are significant differences between the white and the ochre pigments, both in terms of actual temperatures and short-term thermal responses. Noticeably, the white paint exhibits (relatively) large thermal fluctuations, as compared to the ochre or the rock, over the 20-s to 1-min timescale; these thermal variations may induce pigment-to-pigment stresses within the painting. The pigmented areas also exhibit different temperatures to the surrounding paint-free rock, suggesting that there may be both within-painting and between painting and rock (including the rock beneath the painting) stresses that can lead to degradation. Humidity data were found to be inadequate for any meaningful evaluation of the moisture conditions.

  8. Geochemical characterization of a Holocene aeolian profile in the Zhongba area (southern Tibet, China) and its paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Li, Tuoyu; Wu, Yongqiu; Du, Shisong; Huang, Wenmin; Hao, Chengzhi; Guo, Chao; Zhang, Mei; Fu, Tianyang

    2016-03-01

    The Zhongba area lies in the valley of the Maquan River in southern Tibet, where there are both strong modern aeolian activities and ancient aeolian sand sediments. A Holocene aeolian sand and paleosol profile in the Zhongba area was selected for study and termed (Zhuzhu (ZZ) profile). The chronology of the ZZ profile was established by optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C dating. Based on the grain size and geochemical elements of the ZZ profile, the geochemical characterization was analyzed, the Holocene aeolian activity processes were reconstructed in the study area, and the paleoclimatic implications were discussed. The major elements and the chemical indicators are highly correlated with different grain-sizes in the ZZ profile. The evolutionary sequence of the aeolian activities and the paleoclimate in Holocene reveal four stages: before 7.3 ka BP, the climate was warm and wet with weak winds when the sand paleosol developed; at 7.3-3.8 ka BP, the climate turned dry, with strong aeolian activities; at 3.8-0.7 ka BP, the climate became wetter and the winds weakened when the silt paleosol developed; and since 0.7 ka BP, it was cold and dry with strong aeolian activities.

  9. Genetic variation in insecticide tolerance in a population of southern leopard frogs (Rana sphenocephala): Implications for amphibian conservation

    USGS Publications Warehouse

    Bridges, C.M.; Semlitsch, R.D.

    2001-01-01

    Currently, conservation efforts are devoted to determining the extent and the causes of the decline of many amphibian species worldwide. Human impacts frequently degrade amphibian habitat and have been implicated in many declines. Because genetic variance is critical in determining the persistence of a species in a changing environment, we examined the amount of genetic variability present in a single population for tolerance to an environmental stressor. We examined the amount of genetic variability among full- and half-sib families in a single population of southern leopard frogs (Rana sphenocephala) with respect to their tolerance to lethal concentrations of the agricultural chemical, carbaryl. Analysis of time-to-death data indicated significant differences among full-sib families and suggests a large amount of variability present in the responses to this environmental stressor. Significant differences in responses among half-sib families indicated that there is additive genetic variance. These data suggest that this population may have the ability to adapt to environmental stressors. It is possible that declines of amphibian populations in the western United States may be attributed to low genetic variability resulting from limited migration among populations and small population sizes.

  10. A sediment budget for the southern reach in San Francisco Bay, CA: implications for habitat restoration

    USGS Publications Warehouse

    Shellenbarger, Gregory; Wright, Scott A.; Schoellhamer, David H.

    2013-01-01

    The South Bay Salt Pond Restoration Project is overseeing the restoration of about 6000 ha of former commercial salt-evaporation ponds to tidal marsh and managed wetlands in the southern reach of San Francisco Bay (SFB). As a result of regional groundwater overdrafts prior to the 1970s, parts of the project area have subsided below sea-level and will require between 29 and 45 million m3 of sediment to raise the surface of the subsided areas to elevations appropriate for tidal marsh colonization and development. Therefore, a sufficient sediment supply to the far south SFB subembayment is a critical variable for achieving restoration goals. Although both major tributaries to far south SFB have been seasonally gaged for sediment since 2004, the sediment flux at the Dumbarton Narrows, the bayward boundary of far south SFB, has not been quantified until recently. Using daily suspended-sediment flux data from the gages on Guadalupe River and Coyote Creek, combined with continuous suspended-sediment flux data at Dumbarton Narrows, we computed a sediment budget for far south SFB during Water Years 2009–2011. A Monte Carlo approach was used to quantify the uncertainty of the flux estimates. The sediment flux past Dumbarton Narrows from the north dominates the input to the subembayment. However, environmental conditions in the spring can dramatically influence the direction of springtime flux, which appears to be a dominant influence on the net annual flux. It is estimated that up to several millennia may be required for natural tributary sediments to fill the accommodation space of the subsided former salt ponds, whereas supply from the rest of the bay could fill the space in several centuries. Uncertainty in the measurement of sediment flux is large, in part because small suspended-sediment concentration differences between flood and ebb tides can lead to large differences in total mass exchange. Using Monte Carlo simulations to estimate the random error associated with

  11. Varena suite in the crystalline crust of the Southern Lithuania: implication to the genesis and mineralization

    NASA Astrophysics Data System (ADS)

    Kirkliauskaite, Vaida; Motuza, Gediminas; Skipityte, Raminta

    2016-04-01

    Keywords: Lithuania, Proterozoic, Varena suite, rare earth elements, metasomatosis. Crystalline crust in Southern Lithuania is covered by 200-500 m thick sedimentary cover and is investigated by potential field mapping and drilling. It is composed by amphibolites (metabasalts), biotite-quartz-plagioclase gneisses (metapsammites and porphyry metadacite and metaandesite) of Orosirian period. Each lithology is predominant in alternating bands extended NNE-SSW. Supracrustals are metamorphosed on the level of amphibolite facies and migmatized. Intrusive rocks are represented by coeval rare bodies of gabbro, peridotite and widespread Calymmian granitic plutons. Varena suite comprises olivine, enstatite, diopside, olivine-magnetite, magnetite, apatite-bearing, and presumably also dolomite rocks. They form integrated bodies few sq. km large, concentrated in the ˜300 km2area extended in N-S direction.Bodies of particular rocks from Varena suite fixed in the boreholes are few tenths up to few hundred meters thick, except apatite-bearing rocks, forming decimeter up to meter scale lenses and veins. Rocks of Varena suite are affected by strong metasomatic alteration. Olivine is substituted by serpentine, and phlogopite, pyroxenes with amphibols (hornblende, actinolite, tremolite, rarely richterite). The country rocks (amphibolites, metaporphyres) also affected by alkaline (mainly sodic) metasomatosis manifested by formation of scapolite, albite, clynopyroxene (often sodic), phlogopite, carbonates. The mineralization of REE (up to 2759-3100 ppm of La and Ce respectively), Th, U, P hosted by monazite, apatite, allanite is spatially related to the Varena suite and some metasomatized supracrustals. The views on the genesis of Varena suite are contradicting. By various authors they are regarded as skarns, presuming metasomatic origin, as layered intrusions or products of alkaline and carbonatitic magmatism. In this presentation the genetic model is reviewed based on

  12. Spatial and temporal deformation along the northern San Jacinto fault, southern California: Implications for slip rates

    USGS Publications Warehouse

    Kendrick, K.J.; Morton, D.M.; Wells, S.G.; Simpson, R.W.

    2002-01-01

    The San Timoteo badlands is an area of uplift and erosional dissection that has formed as a result of late Quaternary uplift along a restraining bend in the San Jacinto fault, of the San Andreas fault system in southern California. This bend currently is located in a region where late Quaternary deposits and associated surfaces have formed in lower San Timoteo Canyon. We have used morphometric analysis of these surfaces, in conjunction with computer modeling of deformational patterns along the San Jacinto fault, to reconstruct spatial and temporal variations in uplift along the bend. Morphometric techniques used include envelope/subenvelope mapping, a gradient-length index along channels, and denudation values. Age control is determined using a combination of thermoluminescence (TL) and near infrared optical simulation luminescence dating (IROSL) and correlation of soil-development indices. These approaches are combined with an elastic half-space model used to determine the deformation associated with the fault bend. The region of modeled uplift has a similar distribution as that determined by morphometric techniques. Luminescence dates and soil-correlation age estimates generally agree. Based on soil development, surfaces within the study area were stabilized at approximately 300-700 ka for Q3, 43-67 ka for Q2, and 27.5-67 ka for Q1. Luminescence ages (both TL and IROSL) for the formation of the younger two surfaces are 58 to 94 ka for Q2 and 37 to 62 ka for Q1 (ages reported to 1?? uncertainty). Periods of uplift were determined for the surfaces in the study area, resulting in approximate uplift rates of 0.34 to 0.84 m/ka for the past 100 ka and 0.13 to 1.00 m/ka for the past 66 ka. Comparison of these rates of uplift to those generated by the model support a higher rate of lateral slip along the San Jacinto fault than commonly assumed (greater than 20 mm/yr, as compared to 8-12 mm/yr commonly cited). This higher slip rate supports the proposal that a greater

  13. Laboratory diagnosis of Ebola hemorrhagic fever during an outbreak in Yambio, Sudan, 2004.

    PubMed

    Onyango, Clayton O; Opoka, Martin L; Ksiazek, Thomas G; Formenty, Pierre; Ahmed, Abdullahi; Tukei, Peter M; Sang, Rosemary C; Ofula, Victor O; Konongoi, Samson L; Coldren, Rodney L; Grein, Thomas; Legros, Dominique; Bell, Mike; De Cock, Kevin M; Bellini, William J; Towner, Jonathan S; Nichol, Stuart T; Rollin, Pierre E

    2007-11-15

    Between the months of April and June 2004, an Ebola hemorrhagic fever (EHF) outbreak was reported in Yambio county, southern Sudan. Blood samples were collected from a total of 36 patients with suspected EHF and were tested by enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G and M antibodies, antigen ELISA, and reverse-transcription polymerase chain reaction (PCR) of a segment of the Ebolavirus (EBOV) polymerase gene. A total of 13 patients were confirmed to be infected with EBOV. In addition, 4 fatal cases were classified as probable cases, because no samples were collected. Another 12 patients were confirmed to have acute measles infection during the same period that EBOV was circulating. Genetic analysis of PCR-positive samples indicated that the virus was similar to but distinct from Sudan EBOV Maleo 1979. In response, case management, social mobilization, and follow-up of contacts were set up as means of surveillance. The outbreak was declared to be over on 7 August 2004.

  14. Islands of Education: Schooling, Civil War and the Southern Sudanese (1983-2004)

    ERIC Educational Resources Information Center

    Sommers, Marc

    2005-01-01

    Victims of warfare, famine, slavery, and isolation, the Southern Sudanese are one of the most undereducated populations in the world. Since the inception of formal education in southern Sudan a century ago, schooling has largely consisted of island-like entities surrounded by oceans of educational emptiness. Islands of Education is the first book…

  15. An Extreme Precipitation Event in Southern Morocco in Spring 2002 and some Hydrological Implications

    NASA Astrophysics Data System (ADS)

    Knippertz, P.; Fink, A. H.

    2003-04-01

    This paper describes an extreme rain event in the semiarid to arid region south of the High Atlas in northwest Africa on 31 March and 01 April 2002. Apart from European Centre for Medium-Range Weather Forecasts analyses, satellite, radiosonde and synoptic weather station data, half-hourly observations from 12 climate stations that have been recently installed in the Drâa valley in southern Morocco as part of the IMPETUS project ("An Integrated Approach to the Efficient Management of Scarce Water Resources in West Africa") are considered. Precipitation totals (of up to 77 mm in 23 hours) range in the order of magnitude of more than half of an average annual sum and constitute the heaviest storm of the last 25 years in this region. The immediate run-off caused flooding and damage to buildings. Besides, a substantial filling of water reservoirs (+23.6% of the total capacity of the great storage lake Mansour Eddahbi) and a storage of water in the High Atlas snow cover (up to 1 m) and in the soil was observed, which positively impacted on the region's water supply until the summer. The precipitation event was connected to a "tropical plume" (TP) that formed on the eastern side of an quasi-stationary upper-level subtropical trough to the west of northwestern Africa during the previous days. The large positive potential vorticity (PV) anomaly associated with this trough suggests an intrusion of dry stratospheric air connected to an anticyclonic Rossby wave breaking event. This PV anomaly interacted with the low-level temperature front connected to the TP, initiating the development of a Mediterranean cyclone on the poleward side of the TP over the course of the following days. On 01 April, the merging of the TP with the cold air cloud feature resulted in the formation of a lambda-shaped cloud system, sometimes referred to as an "instant occlusion". A trajectory and integrated water vapour flux analysis reveals that on the equatorward side of the TP, mid-level moisture

  16. Development of sedimentary cycles on the east Sahara craton since Silurian time (northwest Sudan/southwest Egypt)

    SciTech Connect

    Wycisk, P. )

    1988-08-01

    The sedimentary succession of southwest Egypt and northwest Sudan, formerly called the Nubia(n) Sandstone, has been subdivided into a number of formations. The predominantly fluvial sediments which characterize Silurian to Upper Cretaceous strata of this region were repeatedly interrupted by marine transgressions that rapidly progressed toward the south since Ordovician time. Thin, shallow marine sequences of different ages can be traced for more than 1,000 km within the studied area. The development of the sedimentary cycles will be pointed out by surface and subsurface data along a cross section from the southern Dakhla basin in the north to the Misaha trough and Abyad basin in the south.

  17. Late Quaternary tectonics in the inner Northern Apennines (Siena Basin, southern Tuscany, Italy) and their seismotectonic implication

    NASA Astrophysics Data System (ADS)

    Brogi, Andrea; Capezzuoli, Enrico; Martini, Ivan; Picozzi, Matteo; Sandrelli, Fabio

    2014-05-01

    Defining the most recent Quaternary tectonics represents a challenging task for neotectonic, palaeoseismological and seismotectonic studies. This paper focuses on an integrated approach to reconstructing the latest Quaternary deformation affecting the northern part of the Siena Basin (inner Northern Apennines, i.e., southern Tuscany, Italy) near the town of Siena, and to discuss the seismological implications. Field work and structural and stratigraphic analyses, coupled with the interpretation of reflection seismic lines, have been combined to define the geometry, kinematics and age of mesoscopic to map-scale faults which have affected the mainly Quaternary continental and Pliocene marine deposits. The resulting dataset describes a tectonic setting characterized by coeval SW- and NW-trending transtensional and normal faults, respectively, dissecting alluvial sediments younger than 23.9 ± 0.23 ka. Seismic interpretation sheds light on the geometrical setting of the faults at deeper levels, down to 1-2 km, and provides support for the presence of a wide brittle shear zone defined by conjugated fault segments, locally giving rise to an asymmetrical negative flower-like structure. Faults and their damage zones have controlled (and still control) the discharge of gas vents (mainly CO2 and H2S) and hydrothermal circulation (which deposits travertine) since at least 23.216 ± 0.124 ka. The resulting complete data set provides support for our description of the Neogene-Quaternary tectonics which were active until the late Quaternary, providing additional information about the seismotectonic framework of an area characterized by low seismicity and generally low-magnitude earthquakes (M < 4), but having experienced significant seismic events over the last few centuries.

  18. Exploitation and recovery of a sea urchin predator has implications for the resilience of southern California kelp forests

    PubMed Central

    Hamilton, Scott L.; Caselle, Jennifer E.

    2015-01-01

    Size-structured predator–prey interactions can be altered by the history of exploitation, if that exploitation is itself size-selective. For example, selective harvesting of larger sized predators can release prey populations in cases where only large individuals are capable of consuming a particular prey species. In this study, we examined how the history of exploitation and recovery (inside marine reserves and due to fisheries management) of California sheephead (Semicossyphus pulcher) has affected size-structured interactions with sea urchin prey in southern California. We show that fishing changes size structure by reducing sizes and alters life histories of sheephead, while management measures that lessen or remove fishing impacts (e.g. marine reserves, effort restrictions) reverse these effects and result in increases in density, size and biomass. We show that predation on sea urchins is size-dependent, such that the diet of larger sheephead is composed of more and larger sized urchins than the diet of smaller fish. These results have implications for kelp forest resilience, because urchins can overgraze kelp in the absence of top-down control. From surveys in a network of marine reserves, we report negative relationships between the abundance of sheephead and urchins and the abundance of urchins and fleshy macroalgae (including giant kelp), indicating the potential for cascading indirect positive effects of top predators on the abundance of primary producers. Management measures such as increased minimum size limits and marine reserves may serve to restore historical trophic roles of key predators and thereby enhance the resilience of marine ecosystems. PMID:25500572

  19. Exploitation and recovery of a sea urchin predator has implications for the resilience of southern California kelp forests.

    PubMed

    Hamilton, Scott L; Caselle, Jennifer E

    2015-01-22

    Size-structured predator-prey interactions can be altered by the history of exploitation, if that exploitation is itself size-selective. For example, selective harvesting of larger sized predators can release prey populations in cases where only large individuals are capable of consuming a particular prey species. In this study, we examined how the history of exploitation and recovery (inside marine reserves and due to fisheries management) of California sheephead (Semicossyphus pulcher) has affected size-structured interactions with sea urchin prey in southern California. We show that fishing changes size structure by reducing sizes and alters life histories of sheephead, while management measures that lessen or remove fishing impacts (e.g. marine reserves, effort restrictions) reverse these effects and result in increases in density, size and biomass. We show that predation on sea urchins is size-dependent, such that the diet of larger sheephead is composed of more and larger sized urchins than the diet of smaller fish. These results have implications for kelp forest resilience, because urchins can overgraze kelp in the absence of top-down control. From surveys in a network of marine reserves, we report negative relationships between the abundance of sheephead and urchins and the abundance of urchins and fleshy macroalgae (including giant kelp), indicating the potential for cascading indirect positive effects of top predators on the abundance of primary producers. Management measures such as increased minimum size limits and marine reserves may serve to restore historical trophic roles of key predators and thereby enhance the resilience of marine ecosystems.

  20. Kangaroo tooth enamel oxygen and carbon isotope variation on a latitudinal transect in southern Australia: implications for palaeoenvironmental reconstruction.

    PubMed

    Brookman, Tom H; Ambrose, Stanley H

    2013-02-01

    Tooth enamel apatite carbonate carbon and oxygen isotope ratios of modern kangaroos (Macropus spp.) collected on a 900-km latitudinal transect spanning a C(3)-C(4) transition zone were analysed to create a reference set for palaeoenvironmental reconstruction in southern Australia. The carbon isotope composition of enamel carbonate reflects the proportional intake of C(3) and C(4) vegetation, and its oxygen isotope composition reflects that of ingested water. Tooth enamel forms incrementally, recording dietary and environmental changes during mineralisation. Analyses show only weak correlations between climate records and latitudinal changes in δ(13)C and δ(18)O. No species achieved the δ(13)C values (~-1.0 ‰) expected for 100 % C(4) grazing diets; kangaroos at low latitudes that are classified as feeding primarily on C(4) grasses (grazers) have δ(13)C of up to -3.5 ‰. In these areas, δ(13)C below -12 ‰ suggests a 100 % C(3) grass and/or leafy plant (browse) diet while animals from higher latitude have lower δ(13)C. Animals from semi-arid areas have δ(18)O of 34-40 ‰, while grazers from temperate areas have lower values (~28-30 ‰). Three patterns with implications for palaeoenvironmental reconstruction emerge: (1) all species in semi-arid areas regularly browse to supplement limited grass resources; (2) all species within an environmental zone have similar carbon and oxygen isotope compositions, meaning data from different kangaroo species can be pooled for palaeoenvironmental investigations; (3) relatively small regional environmental differences can be distinguished when δ(13)C and δ(18)O data are used together. These data demonstrate that diet-isotope and climate-isotope relationships should be evaluated in modern ecosystems before application to the regional fossil record.

  1. Cutaneous Emergence of Eustrongylides in Two Persons from South Sudan

    PubMed Central

    Eberhard, Mark L.; Ruiz-Tiben, Ernesto

    2014-01-01

    Two large, living worms were collected as they emerged from the lower limb of each of two persons in South Sudan. The worms were observed by staff of the South Sudan Guinea Worm Eradication Program during surveillance activities in communities at-risk for cases of Guinea worm disease (dracunculiasis). The worms measured 7 and 8 cm in length and were identified as fourth-stage larvae of Eustrongylides. This is the first report of such worms emerging from the skin; all five previous reports of human infection involved surgical removal of worms from the peritoneal cavity. PMID:24379241

  2. Morphological Analysis of Apo Volcanic Complex in Southern Mindanao, Philippines: implications on volcano-tectonic evolution of different volcanic units

    NASA Astrophysics Data System (ADS)

    Herrero, T. M. L.; van Wyk de Vries, B.; Lagmay, A. M. A.; Eco, R. C.

    2015-12-01

    The Apo Volcanic Complex (AVC) is one of the largest volcanic centers in the Philippines, located in the southern island of Mindanao. It is composed of four edifices and several smaller cones. The youngest volcanic unit, the Apo Dome, is the highest elevation in the Philippines. This unit is classified as potentially active, whereas other units, Talomo, Sibulan and Kitubod, are inactive. The study gives insight to the construction and deformation history of the volcanic units and imparts foresight to subsequent events that can affect populated areas. A morphological analysis integrating high-resolution digital terrain models and public domain satellite data and images was done to recognize and discriminate volcanic units and characterize volcano-tectonic features and processes. Morphological domains were defined based on surface textures, slope variation, degrees and controls of erosion, and lineament density and direction. This establishes the relative ages and extent of volcanic units as well as the volcano-tectonic evolution of the complex. Six edifice building events were recognized, two of which form the elevated base of Apo dome. The geodynamic setting of the region is imprinted in the volcanic units as five morphostructural lineaments. They reveal the changes in maximum regional stress through time such as the N-S extension found across the whole volcanic complex displaying the current stress regime. This has implications on the locality and propagation of geothermal activity, magma ascent, and edifice collapses. One main result of the compounded effects of inherited structures and current stress regime is the Sandawa Collapse Zone. This is a large valley formed by several collapses where NE-SW fractures propagate and the increasing lateral spreading by debuttressing continue to eat away the highest peak. The AVC is surrounded by the major metropolitan area of Davao City to the east and the cities of Kidapawan and Digos to the west and south, respectively

  3. VOLATILE ORGANIC COMPOUNDS FROM VEGETATION IN SOUTHERN YUNNAN PROVINCE, CHINA: EMISSION RATES AND SOME POTENTIAL REGIONAL IMPLICATIONS

    EPA Science Inventory

    Little information is currently available regarding emissions of biogenic volatile organic compounds (BVOCs) in southern Asia. To address the need for BVOC emission estimates in regional atmospheric chemistry simulations, 95 common plant species were screened for emissions of BVO...

  4. The Role of Education in Sudan's Civil War

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2013-01-01

    This article addresses the role that education plays in conflict, with specific reference to the civil war in Sudan. It analyses the ideological basis of the Sudanese government (GoS) during the civil war, with special reference to the role of religion and ethnicity. It shows how the primary education system was based on the Islamist ideology of…

  5. Child Prodigy in Astronomy: A Biographical Study from the Sudan

    ERIC Educational Resources Information Center

    Khaleefa, Omar

    2009-01-01

    Although many studies have been conducted in the West regarding child prodigies, no such studies have taken place in indigenous Arab cultures--particularly not in Sudan. The present study attempts to bridge the existing gap in this area by focusing on a Sudanese child prodigy with extraordinary inclination towards astronomy. It is a qualitative…

  6. Sudanese Images of the Other: Education and Conflict in Sudan

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2010-01-01

    Education can contribute to peace and reconciliation as well as to conflict and strife. The complex, often contradictory role of education in conflict is explored in this article in relation to Sudan. The focus of the article is the North-South conflict, bearing in mind that other, "minor" wars and military clashes in both the North and South have…

  7. Linkages between Southern Ocean Cloud-Radiative Processes and the Large-Scale Southern Hemisphere Circulation, and Their Implications for Climate Model Projections

    NASA Astrophysics Data System (ADS)

    Grise, K. M.; Polvani, L. M.

    2014-12-01

    Southern Ocean cloud cover is strongly linked to extratropical weather systems, and thus to the position of the Southern Hemisphere (SH) storm track and the mid-latitude eddy-driven jet stream. Consequently, if the jet moves poleward (either as a result of natural variability or anthropogenic forcing), a notable change in cloud-radiative processes might be expected. In this study, we examine the cloud-radiative anomalies associated with interannual variability in the latitude of the SH mid-latitude eddy-driven jet, using two satellite data sets (ISCCP-FD and CERES) and 20 global climate models from Phase 5 of the Coupled Model Intercomparison Project (CMIP5). Two distinct model types are found. In the first class of models ("type I models"), the total cloud fraction is reduced at SH mid-latitudes as the jet moves poleward, contributing to enhanced shortwave radiative warming. In the second class of models ("type II models"), this dynamically-induced cloud-radiative warming effect is largely absent. Type I and type II models have distinct deficiencies in their representation of observed Southern Ocean clouds, but comparison with the two satellite data sets indicates that the cloud-dynamics behavior of type II models is more realistic. Because the SH mid-latitude jet shifts poleward in response to CO2 forcing, the cloud-dynamics biases uncovered from interannual variability are directly relevant for climate change projections. In CMIP5 model experiments with abruptly quadrupled atmospheric CO2 concentrations, the global-mean surface temperature initially warms more in type I models, even though their equilibrium climate sensitivity is not significantly larger. In type I models, this larger initial warming is linked to the rapid adjustment of the circulation and clouds to CO2 forcing in the SH, where a nearly instantaneous poleward shift of the mid-latitude jet is accompanied by a reduction in the reflection of solar radiation by clouds. In type II models, the SH jet

  8. Physical- and geochemical properties of core samples from the Swedish part of the southern Baltic Sea: Implications for CO2 storage

    NASA Astrophysics Data System (ADS)

    Elhami, Ehsan; Erlström, Mikael; Ask, Maria; Mattsson, Hans

    2016-04-01

    Feasibility studies of CO2 storage in Sweden has been conducted based on the geological and geophysical data from the southern Baltic Sea (e.g. Juhlin et al., 2013). One suitable formation for CO2 storage may exist below southern Gotland, with good aquifer properties for storage and suitable caprock. We present detailed results from a series of measurements conducted on core samples consisting of Cambrian sandstone (potential reservoir rock) and Ordovician limestone (potential caprock). The core samples are provided by Geological Survey of Sweden (SGU) and were collected from 146-586 m depth. The experiments consist of petrophysical properties measurements (density, porosity, permeability, thermal conductivity and P-wave velocity) and chemical analysis. The two rock types reveal contrasting properties, for example density and P-wave velocity is 2.26±0.13 gr/cm3 and 3.14±1.00 km/s, respectively, for the sandstone (reservoir rock) while significantly higher values were obtained for the limestone (caprock), 2.58±0.08 gr/cm3 and 6.09±0.24 km/s respectively. The objective of this study is to evaluate the interrelationships between the obtained petrophysical and geochemical properties from southern Swedish Baltic Sea to better understand the implications of the evaluated properties for CO2 storage in Sweden.

  9. Reworked planktonic Foraminifera from the Late Rupelian of the southern Upper Rhine Graben and their palaeogeographic and biostratigraphic implications

    NASA Astrophysics Data System (ADS)

    Pirkenseer, C.; Spezzaferri, S.; Berger, J.-P.

    2009-04-01

    margin of the Upper Rhine Graben. Reworked Mesozoic and Paleogene calcareous nannoplankton from the Upper Rhine Graben and the Mainz Basin confirms the data derived from planktonic Foraminifera. The existence of reworked planktonic Foraminifera influences the biostratigraphic interpretation of the assemblage ranges attributed to "Série grise" samples. Facultatively reworked planktonic Foraminifera as Subbotina utilisindex and Pseudohastigerina micra ranging from the Lutetian to the Late Rupelian should not be included in the biostratigraphic analyses, as the occurrences of these facultatively reworked species are always linked to those of exclusively Cretaceous and Eocene age. Therefore the age of the "Série grise" deposits at Allschwil-2 is most likely to be placed within the "Chiloguembelina cubensis - Globigerinella obesa / Globorotaloides variabilis"-assemblage range of Mid P20 to Final P21a, lasting considerably longer than the very short Mid P20 range based on the presence of Pseudohastigerina micra as "last occurrence"-marker (PIRKENSEER 2007). This study was funded by the Swiss National Science Foundation projects 109457 and 118025. References: BERGER, J.-P., REICHENBACHER, B., BECKER, D., et al. (2005): Eocene-Pliocene time scale and stratigraphy of the Upper Rhine Graben (URG) and the Swiss Molasse Basin (SMB). - International Journal of Earth Sciences, 94, 4: 711-731. FISCHER, H. (1965): Geologie des Gebietes zwischen Blauen und Pfirter Jura. - Beiträge zur geologischen Karte der Schweiz, NF 122: 106p. PIRKENSEER, C. (2007): Foraminifera, Ostracoda and other microfossils of the Southern Upper Rhine Graben - Palaeoecology, biostratigraphy, palaeogeography and geodynamic implications. - PhD thesis: 340p, Fribourg. ROUSSÉ, S. (2006): Architecture et dynamique des séries marines et continentales de ĺOligocène Moyen et Supérieur du Sud du Fossé Rhénan: Evolution des milieux de dépôt en contexte de rift en marge de ĺavant-pays alpin. - PhD: 471p

  10. The influence of extreme winds on coastal oceanography and its implications for coral population connectivity in the southern Arabian Gulf.

    PubMed

    Cavalcante, Geórgenes H; Feary, David A; Burt, John A

    2016-04-30

    Using long-term oceanographic surveys and a 3-D hydrodynamic model we show that localized peak winds (known as shamals) cause fluctuation in water current speed and direction, and substantial oscillations in sea-bottom salinity and temperature in the southern Persian/Arabian Gulf. Results also demonstrate that short-term shamal winds have substantial impacts on oceanographic processes along the southern Persian/Arabian Gulf coastline, resulting in formation of large-scale (52 km diameter) eddies extending from the coast of the United Arab Emirates (UAE) to areas near the off-shore islands of Iran. Such eddies likely play an important role in transporting larvae from well-developed reefs of the off-shore islands to the degraded reef systems of the southern Persian/Arabian Gulf, potentially maintaining genetic and ecological connectivity of these geographically distant populations and enabling enhanced recovery of degraded coral communities in the UAE.

  11. The influence of extreme winds on coastal oceanography and its implications for coral population connectivity in the southern Arabian Gulf.

    PubMed

    Cavalcante, Geórgenes H; Feary, David A; Burt, John A

    2016-04-30

    Using long-term oceanographic surveys and a 3-D hydrodynamic model we show that localized peak winds (known as shamals) cause fluctuation in water current speed and direction, and substantial oscillations in sea-bottom salinity and temperature in the southern Persian/Arabian Gulf. Results also demonstrate that short-term shamal winds have substantial impacts on oceanographic processes along the southern Persian/Arabian Gulf coastline, resulting in formation of large-scale (52 km diameter) eddies extending from the coast of the United Arab Emirates (UAE) to areas near the off-shore islands of Iran. Such eddies likely play an important role in transporting larvae from well-developed reefs of the off-shore islands to the degraded reef systems of the southern Persian/Arabian Gulf, potentially maintaining genetic and ecological connectivity of these geographically distant populations and enabling enhanced recovery of degraded coral communities in the UAE. PMID:26506023

  12. Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Nino-Southern Oscillation records

    USGS Publications Warehouse

    Keefer, David K.; Moseley, Michael E.

    2004-01-01

    In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2-8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term "shattered landscape" to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Nin??o events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Nin??o-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion.

  13. Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Niño–Southern Oscillation records

    PubMed Central

    Keefer, David K.; Moseley, Michael E.

    2004-01-01

    In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2–8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term “shattered landscape” to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Niño events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Niño-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion. PMID:15263069

  14. Base- and precious-metal deposits in the Basin and Range of Southern California and Southern Nevada - Metallogenic implications of lead isotope studies

    USGS Publications Warehouse

    Church, S.E.; Cox, D.P.; Wooden, J.L.; Tingley, J.V.; Vaughn, R.B.

    2005-01-01

    Southern California and southern Nevada contain abundant lead-zinc deposits with strikingly different characteristics. On the west, the Darwin Terrane contains abundant Jurassic and Cretaceous intrusions surrounded by lead-zinc skarn and replacement deposits rich in pyrite and manganese minerals. The Tecopa Terrane is east of the Darwin Terrane and contains some lead deposits that are hosted by the Proterozoic Noonday Dolomite. These lead deposits have no consistent relation to igneous rocks; they contain mainly galena, and are devoid of pyrite and manganese minerals. Other skarn and vein deposits in the Ivanpah and Tecopa districts are more closely associated with igneous rocks. Mississippi Valley type lead-zinc deposits are present still farther to the east in the Goodsprings Terrane in Nevada. These deposits are hosted by breccias formed below the Mississippian-Pennsylvanian unconformity and are unrelated to igneous rocks. Deposits in the Darwin Terrane have lead isotopic signatures that lie along a mantle-sediment mixing line indicating that they formed in a continental arc setting analogous to that for the plutons in the Sierra Nevada batholith [Chen, J.H. and Tilton, G.R., 1991. Application of lead and strontium isotopic relationships to the petrogenesis of granitoid rocks, central Sierra Nevada batholith, California. Geological Society of America Bulletin 103, 439-447]. Encroachment of this continental arc on the North American continent in the eastern part of the Darwin Terrane resulted in a lead isotopic signature that is like that of the strongly contaminated plutons [Chen, J.H. and Tilton, G.R., 1991. Application of lead and strontium isotopic relationships to the petrogenesis of granitoid rocks, central Sierra Nevada batholith, California. Geological Society of America Bulletin 103, 439-447]. Many deposits from the Inyo Mountains on east side of the Owens Valley have lead isotopic signatures that reflect this encroachment. To the east in the Tecopa

  15. New chronology for the southern Kalahari Group sediments - implications for sediment-cycle dynamics and basin development

    NASA Astrophysics Data System (ADS)

    Matmon, Ari; Hidy, Alan; Vainer, Shlomy; Crouvi, Onn; Fink, David; Erel, Yigal; Aster Team; Horwitz, Liora; Chazan, Michael

    2016-04-01

    Kalahari Group sediments accumulated in the Kalahari basin, which started forming during the breakup of Gondwana in the early Cretaceous. These sediments cover an extensive part of southern Africa and form a low-relief landscape. Current models assume that the Kalahari Group accumulated throughout the entire Cenozoic. However, chronology has been restricted to early-middle Cenozoic biostratigraphic correlations and to OSL dating of only the past ~300 ka. We present a new chronological framework that reveals a dynamic nature of sedimentation in the southern Kalahari. Cosmogenic burial ages obtained from a 55 m section of Kalahari Group sediments from the Mamatwan Mine, southern Kalahari, indicate that the majority of deposition at this location occurred rapidly at 1-1.2 Ma. This Pleistocene sequence overlies the Archaean basement, forming a significant hiatus that permits the possibility of many Phanerozoic cycles of deposition and erosion no longer preserved in the sedimentary record. Our data also establish the existence of a shallow early-middle Pleistocene water body that persisted for >450 ka prior to this rapid period of deposition and suggesting an Okavango-like environment. Evidence from neighboring archaeological excavations in southern Africa suggests an association of high-density hominin occupation with this water body.

  16. New chronology for the southern Kalahari Group sediments with implications for sediment-cycle dynamics and early hominin occupation

    NASA Astrophysics Data System (ADS)

    Matmon, Ari; Hidy, Alan J.; Vainer, Shlomy; Crouvi, Onn; Fink, David; Erel, Yigal; Arnold, M.; Aumaître, G.; Bourlès, D.; Keddadouche, K.; Horwitz, Liora K.; Chazan, Michael

    2015-07-01

    Kalahari Group sediments accumulated in the Kalahari basin, which started forming during the breakup of Gondwana in the early Cretaceous. These sediments cover an extensive part of southern Africa and form a low-relief landscape. Current models assume that the Kalahari Group accumulated throughout the entire Cenozoic. However, chronology has been restricted to early-middle Cenozoic biostratigraphic correlations and to OSL dating of only the past ~ 300 ka. We present a new chronological framework that reveals a dynamic nature of sedimentation in the southern Kalahari. Cosmogenic burial ages obtained from a 55 m section of Kalahari Group sediments from the Mamatwan Mine, southern Kalahari, indicate that the majority of deposition at this location occurred rapidly at 1-1.2 Ma. This Pleistocene sequence overlies the Archaean basement, forming a significant hiatus that permits the possibility of many Phanerozoic cycles of deposition and erosion no longer preserved in the sedimentary record. Our data also establish the existence of a shallow early-middle Pleistocene water body that persisted for > 450 ka prior to this rapid period of deposition. Evidence from neighboring archeological excavations in southern Africa suggests an association of high-density hominin occupation with this water body.

  17. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

    PubMed

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program.

  18. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China

    PubMed Central

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China’s afforestation program. PMID:26115116

  19. Late Holocene Marsh Expansion in Southern San Francisco Bay, California: Implications for the Use of Historic Baselines as Restoration Targets

    EPA Science Inventory

    Currently, the largest tidal wetlands restoration project on the US Pacific Coast is being planned and implemented in southern San Francisco Bay; however, knowledge of baseline conditions of salt marsh extent in the region prior to European settlement is limited. Here, analysis o...

  20. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

    PubMed

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program. PMID:26115116

  1. Occurrence of Sudan I in paprika fruits caused by agricultural environmental contamination.

    PubMed

    Lian, Yunhe; Gao, Wei; Zhou, Li; Wu, Naiying; Lu, Qingguo; Han, Wenjie; Tie, Xiaowei

    2014-05-01

    Current research has demonstrated the presence of sub parts per billion levels of Sudan dye in paprika fruits during the vegetation process, which is difficult to understand on the basis of the conventional concept of cross-contamination or malicious addition. Detailed surveys on Sudan dyes I-IV in paprika fruits, soils, and agronomic materials used from seven fields of Xinjiang (China) were conducted to investigate the natural contamination. Results revealed that Sudan dyes II-IV were never detected and that Sudan I existed in almost all samples except for the mulching film and irrigation water. The higher total amount of Sudan I in soils, pesticides, and fertilizers compared to coated seeds indicated the combination of Sudan I-contaminated soils and application of Sudan I-containing agronomic materials constitutes a major source of 0.18-2.52 μg/kg levels of Sudan I in fruits during the growth period. The study offers a more reasonable explanation for the previously observed Sudan I in paprika fruits. PMID:24766082

  2. Occurrence of Sudan I in paprika fruits caused by agricultural environmental contamination.

    PubMed

    Lian, Yunhe; Gao, Wei; Zhou, Li; Wu, Naiying; Lu, Qingguo; Han, Wenjie; Tie, Xiaowei

    2014-05-01

    Current research has demonstrated the presence of sub parts per billion levels of Sudan dye in paprika fruits during the vegetation process, which is difficult to understand on the basis of the conventional concept of cross-contamination or malicious addition. Detailed surveys on Sudan dyes I-IV in paprika fruits, soils, and agronomic materials used from seven fields of Xinjiang (China) were conducted to investigate the natural contamination. Results revealed that Sudan dyes II-IV were never detected and that Sudan I existed in almost all samples except for the mulching film and irrigation water. The higher total amount of Sudan I in soils, pesticides, and fertilizers compared to coated seeds indicated the combination of Sudan I-contaminated soils and application of Sudan I-containing agronomic materials constitutes a major source of 0.18-2.52 μg/kg levels of Sudan I in fruits during the growth period. The study offers a more reasonable explanation for the previously observed Sudan I in paprika fruits.

  3. Logistics of Guinea worm disease eradication in South Sudan.

    PubMed

    Jones, Alexander H; Becknell, Steven; Withers, P Craig; Ruiz-Tiben, Ernesto; Hopkins, Donald R; Stobbelaar, David; Makoy, Samuel Yibi

    2014-03-01

    From 2006 to 2012, the South Sudan Guinea Worm Eradication Program reduced new Guinea worm disease (dracunculiasis) cases by over 90%, despite substantial programmatic challenges. Program logistics have played a key role in program achievements to date. The program uses disease surveillance and program performance data and integrated technical-logistical staffing to maintain flexible and effective logistical support for active community-based surveillance and intervention delivery in thousands of remote communities. Lessons learned from logistical design and management can resonate across similar complex surveillance and public health intervention delivery programs, such as mass drug administration for the control of neglected tropical diseases and other disease eradication programs. Logistical challenges in various public health scenarios and the pivotal contribution of logistics to Guinea worm case reductions in South Sudan underscore the need for additional inquiry into the role of logistics in public health programming in low-income countries.

  4. Value and cost of children in rural Sudan.

    PubMed

    Saghayroun, A A

    1983-12-01

    In this study the major dimensions of the value and cost of children are explained. It is argued that the nature of the production process in rural Sudan is the essential determinant of family size. This study depends mainly upon statistics gathered through surveys conducted in El Sawagi villages in Kassala province between January and May 1979. Children are needed to help on the family farm, looking after cattle and other animals in rural areas or to join the family in business inside and outside the home, and are thus considered as a cheap source of labor under the rural economy in the Sudan. In El Sawagi villages children are seen not only as a prime source of social security for aging parents but also as a source of income right from their childhood. It is because of the agrarian nature of the Sudan and because the system of agriculture is still mainly primitive and subsistence orientated, that children are valuable assets on the large scheme or family farms. Even though children may contribute little labor when the sum is averaged out over the whole year, their labor may be crucial for the poor, at times of peak labor demand. The favorite number of children for a family in El Sawagi villages is more than 4. The cost of rearing and educating a child has probably not yet entered into their calculations. At present, it is still economically beneficial to poor rural families to have a large number of children, although it is not to Sudan's economic benefit. Other social reasons for having children are discussed as well as the disadvantages of having many children.

  5. The 2007 Rift Valley Fever Outbreak in Sudan

    PubMed Central

    Hassan, Osama Ahmed; Ahlm, Clas; Sang, Rosemary; Evander, Magnus

    2011-01-01

    Rift Valley fever (RVF) is a neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health and economy. RVF is caused by RVF virus (RVFV) affecting humans and a wide range of animals. The virus is transmitted through bites from mosquitoes and exposure to viremic blood, body fluids, or tissues of infected animals. During 2007 a large RVF outbreak occurred in Sudan with a total of 747 confirmed human cases including 230 deaths (case fatality 30.8%); although it has been estimated 75,000 were infected. It was most severe in White Nile, El Gezira, and Sennar states near to the White Nile and the Blue Nile Rivers. Notably, RVF was not demonstrated in livestock until after the human cases appeared and unfortunately, there are no records or reports of the number of affected animals or deaths. Ideally, animals should serve as sentinels to prevent loss of human life, but the situation here was reversed. Animal contact seemed to be the most dominant risk factor followed by animal products and mosquito bites. The Sudan outbreak followed an unusually heavy rainfall in the country with severe flooding and previous studies on RVF in Sudan suggest that RVFV is endemic in parts of Sudan. An RVF outbreak results in human disease, but also large economic loss with an impact beyond the immediate influence on the directly affected agricultural producers. The outbreak emphasizes the need for collaboration between veterinary and health authorities, entomologists, environmental specialists, and biologists, as the best strategy towards the prevention and control of RVF. PMID:21980543

  6. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China

    PubMed Central

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B.; Legendre, Louis

    2016-01-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3−), ammonium (NH4+), urea and glycine] and phosphorus [i.e. phosphate (PO43−), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3− and NH4+) and phosphorus (PO43−). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea. PMID:27199215

  7. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China.

    PubMed

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B; Legendre, Louis

    2016-01-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3(-)), ammonium (NH4(+)), urea and glycine] and phosphorus [i.e. phosphate (PO4(3-)), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3(-) and NH4(+)) and phosphorus (PO4(3-)). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea. PMID:27199215

  8. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China

    NASA Astrophysics Data System (ADS)

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B.; Legendre, Louis

    2016-05-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3‑), ammonium (NH4+), urea and glycine] and phosphorus [i.e. phosphate (PO43‑), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3‑ and NH4+) and phosphorus (PO43‑). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea.

  9. Country report of the Democratic Republic of the Sudan.

    PubMed

    Osman, A

    1982-01-01

    Reports on current activities in training of nonphysician personnel for maternal-child health/family health care delivery in Sudan. Lists are provided for the following: the 5 types of facilities operated by the Ministry of Health; other training and services projects; and The Sudan Family Planning Association activities. It is felt that all of these activities need strengthening in the training component. The following projects are being planned by the Khartoum College of Nursing: 1) a family planning project in conjunction with the nutrition clinic in the Children's Hospital; 2) a family planning project in the Gazera irrigated area where community development projects are in existence; 3) a movement into the rural areas of 6 regions of the country of the Sudan Women's Union Health Education Program for Women Leaders; 4) a project for providing free maternity service to needy mothers through maternity homes located within easy reach. These homes are intended to give service and at the same time act as training centers in maternal-child health/family health care for nonphysician personnel.

  10. Malaria Risk Mapping for Control in the Republic of Sudan

    PubMed Central

    Noor, Abdisalan M.; ElMardi, Khalid A.; Abdelgader, Tarig M.; Patil, Anand P.; Amine, Ahmed A. A.; Bakhiet, Sahar; Mukhtar, Maowia M.; Snow, Robert W.

    2012-01-01

    Evidence shows that malaria risk maps are rarely tailored to address national control program ambitions. Here, we generate a malaria risk map adapted for malaria control in Sudan. Community Plasmodium falciparum parasite rate (PfPR) data from 2000 to 2010 were assembled and were standardized to 2–10 years of age (PfPR2–10). Space-time Bayesian geostatistical methods were used to generate a map of malaria risk for 2010. Surfaces of aridity, urbanization, irrigation schemes, and refugee camps were combined with the PfPR2–10 map to tailor the epidemiological stratification for appropriate intervention design. In 2010, a majority of the geographical area of the Sudan had risk of < 1% PfPR2–10. Areas of meso- and hyperendemic risk were located in the south. About 80% of Sudan's population in 2011 was in the areas in the desert, urban centers, or where risk was < 1% PfPR2–10. Aggregated data suggest reducing risks in some high transmission areas since the 1960s. PMID:23033400

  11. N Isotopes in Nile Sediments (ethiopia, Sudan)

    NASA Astrophysics Data System (ADS)

    Padoan, M.; Villa, I. M.; Garzanti, E.; Galbusera, M.; Quistini, S.; Peruta, L.; El Kammar, A.

    2009-04-01

    , values vary from 0.51240-0.51242 for tributaries draining basement rocks only (e.g., Gash, wadi Guba) to 0.51275-0.51280 for tributaries draining mostly basaltic rocks (Atbara); tributaries draining both record mixed signals (e.g., 0.51259; Beles). Nd ratios for Atbara sediments correspond closely with signatures of volcanic source rocks (0.51271-0.51298; Pik et al., 1999), revealing involvement of various mantle and crustal components in petrogenesis of flood basalts. Corresponding Nd model ages (tDM) cluster around 0.84 Ga for the mostly volcanic-derived Blue Nile, Atbara, and Main Nile muds, range 1.2 - 1.5 Ga for tributaries draining Ethiopian basement rocks, and reach as high as 2.4 Ga for the Bahr Ez Zeraf. The different Nd isotopic signal between mud and sand samples is closely controlled by mineralogical composition, Nd and other REE being chiefly contributed by ultradense minerals (e.g., monazite), and consequently concentrated in the finest size fractions of each sample (Garzanti et al., 2008). FREYDIER, R., MICHARD, A., DE LANGE G., THOMSON, J., 2001. Nd isotopic composition of Eastern Mediterranean sediments: tracers of the Nile influence during sapropel S1 formation. Mar. Geol., 177, 45-62. GARZANTI, E., ANDÒ, S., VEZZOLI, G., ABDEL MEGID, A.A., EL KAMMAR, A., 2006. Petrology of Nile River sands (Ethiopian and Sudan): Sediment budgets and erosion patterns. Earth Planet. Sci. Lett., 252, 327-341. GARZANTI, E., ANDÒ, S., VEZZOLI, G., 2008. Settling-equivalence of detrital minerals and grain-size dependence of sediment composition. Earth Planet. Sci. Lett. 273, 138-151. HARLAVAN Y., GARZANTI, E., PADOAN, M., EL KAMMAR, A. Geochemical characterization of Nile River sands; Rare earth elements, Pb and Sr isotopes of the fine fraction. In preparation. KROM, M.D., CLIFF, R.A., EIJSINK, L.M., HERUT, B., CHESTER, R., 1999a. The characterisation of Saharan dusts and Nile particulate matter in surface sediments from the Levantine basin using Sr isotopes. Mar. Geol

  12. N Isotopes in Nile Sediments (ethiopia, Sudan)

    NASA Astrophysics Data System (ADS)

    Padoan, M.; Villa, I. M.; Garzanti, E.; Galbusera, M.; Quistini, S.; Peruta, L.; El Kammar, A.

    2009-04-01

    , values vary from 0.51240-0.51242 for tributaries draining basement rocks only (e.g., Gash, wadi Guba) to 0.51275-0.51280 for tributaries draining mostly basaltic rocks (Atbara); tributaries draining both record mixed signals (e.g., 0.51259; Beles). Nd ratios for Atbara sediments correspond closely with signatures of volcanic source rocks (0.51271-0.51298; Pik et al., 1999), revealing involvement of various mantle and crustal components in petrogenesis of flood basalts. Corresponding Nd model ages (tDM) cluster around 0.84 Ga for the mostly volcanic-derived Blue Nile, Atbara, and Main Nile muds, range 1.2 - 1.5 Ga for tributaries draining Ethiopian basement rocks, and reach as high as 2.4 Ga for the Bahr Ez Zeraf. The different Nd isotopic signal between mud and sand samples is closely controlled by mineralogical composition, Nd and other REE being chiefly contributed by ultradense minerals (e.g., monazite), and consequently concentrated in the finest size fractions of each sample (Garzanti et al., 2008). FREYDIER, R., MICHARD, A., DE LANGE G., THOMSON, J., 2001. Nd isotopic composition of Eastern Mediterranean sediments: tracers of the Nile influence during sapropel S1 formation. Mar. Geol., 177, 45-62. GARZANTI, E., ANDÒ, S., VEZZOLI, G., ABDEL MEGID, A.A., EL KAMMAR, A., 2006. Petrology of Nile River sands (Ethiopian and Sudan): Sediment budgets and erosion patterns. Earth Planet. Sci. Lett., 252, 327-341. GARZANTI, E., ANDÒ, S., VEZZOLI, G., 2008. Settling-equivalence of detrital minerals and grain-size dependence of sediment composition. Earth Planet. Sci. Lett. 273, 138-151. HARLAVAN Y., GARZANTI, E., PADOAN, M., EL KAMMAR, A. Geochemical characterization of Nile River sands; Rare earth elements, Pb and Sr isotopes of the fine fraction. In preparation. KROM, M.D., CLIFF, R.A., EIJSINK, L.M., HERUT, B., CHESTER, R., 1999a. The characterisation of Saharan dusts and Nile particulate matter in surface sediments from the Levantine basin using Sr isotopes. Mar. Geol

  13. The fault pattern in the northern Negev and southern Coastal Plain of Israel and its hydrogeological implications for groundwater flow in the Judea Group aquifer

    NASA Astrophysics Data System (ADS)

    Weinberger, G.; Rosenthal, E.

    1994-03-01

    On the basis of a broadly expanding data base, the hydrogeological properties of the Judea Group sequence in the northern Negev and southern Coastal Plain of Israel have been reassessed. The updated subsurface model is based on data derived from water- and oil-wells and on recent large-scale geophysical investigations. A new regional pattern of the reassessed geological through the subsurface of the study area has been revealed. In view of the reassessed geological and hydrological subsurface setting, it appears that the Judea Group aquifer should not be regarded as one continuous and undisturbed hydrological unit; owing to the occurrence of regional faults, its subaquifers are locally interconnected. These subaquifers, which contain mainly high-quality water, are juxtaposed, as a result of faulting, against Kurnub Group sandstones containing brackish paleowater. The latter Group is faulted against late Jurassic formations containing highly saline groundwater. In the Beer Sheva area, the Judea Group aquifer is vertically displaced against the Senonian and Eocene Mt. Scopus and Avdat Groups, which also contain brackish and saline water. In the southern Coastal Plain, major faults locally dissect also the Pleistocene Kurkar Group, facilitating inflow of Mg-rich groundwater deriving from Judea Group dolomites. The new geological evidence and its hydrogeological implications provide new solutions for previously unexplained salinization phenomena.

  14. Sea-Level Rise Implications for Coastal Protection from Southern Mediterranean to the U.S.A. Atlantic Coast

    NASA Astrophysics Data System (ADS)

    Ismail, Nabil; Williams, Jeffress

    2013-04-01

    planning and restoration projects will require a major undertaking by national governments and international institutions. Joint research projects between international organizations such as: USA research centers ( USGS, NOAA, Corps of Engineers), EU sponsored project groups, EU coastal marine centers as well as other world wide coastal research institutes (CoRI, Alexandria) are encouraged to advance the state of the art on managing coasts to adapt to sea level rise employing cost-effective coastal protection technologies. References 1.Williams, S.J.,"Sea-Level Rise Implications for Coastal Regions", Journal of Coastal Research, Vol. 63, 2013. 2.Ismail, N.,Wiegel, R., "Sustainable Solutions for Coastal Zone Management of Lowland and River Delta Coastlines", Proc. International Conference- Littoral 2012, Ostende, Belgium, November 27-29, 2012. 3.Ismail, N., Iskander, M., and El-Sayed, W. "Assessment of Coastal Flooding at Southern Mediterranean with Global Outlook for Lowland Coastal Zones", Proc. International Conference on Coastal Engineering, ASCE, July 1-6, 2012, Santander, Spain. 4.Moser, S. C., Williams,J.S., and Boesch, D. F., " Wicked Challenges at Land's End: Managing Coastal Vulnerability Under Climate Change'', Annual. Review of Environmental Resources, 37:51-78, 2012.

  15. The Discovery of New Deep-Sea Hydrothermal Vent Communities in the Southern Ocean and Implications for Biogeography

    PubMed Central

    Rogers, Alex D.; Tyler, Paul A.; Connelly, Douglas P.; Copley, Jon T.; James, Rachael; Larter, Robert D.; Linse, Katrin; Mills, Rachel A.; Garabato, Alfredo Naveira; Pancost, Richard D.; Pearce, David A.; Polunin, Nicholas V. C.; German, Christopher R.; Shank, Timothy; Boersch-Supan, Philipp H.; Alker, Belinda J.; Aquilina, Alfred; Bennett, Sarah A.; Clarke, Andrew; Dinley, Robert J. J.; Graham, Alastair G. C.; Green, Darryl R. H.; Hawkes, Jeffrey A.; Hepburn, Laura; Hilario, Ana; Huvenne, Veerle A. I.; Marsh, Leigh; Ramirez-Llodra, Eva; Reid, William D. K.; Roterman, Christopher N.; Sweeting, Christopher J.; Thatje, Sven; Zwirglmaier, Katrin

    2012-01-01

    Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than

  16. Paleomagnetism of an east-west transect across the Cascade arc in southern Washington: Implications for regional tectonism

    USGS Publications Warehouse

    Hagstrum, J.T.; Swanson, D.A.; Evarts, R.C.

    1999-01-01

    Paleomagnetic data from a transect across the Cascade arc in southern Washington were collected to test models of vertical axis rotations for this part of the Pacific Northwest and to provide information on the tectonic history of the St. Helens seismic zone. The 75 site-mean directions are divided into three groups based on isotopic, fission track, and stratigraphic ages. Group 1 consists of samples from rocks deposited between 39 and 30 Ma and shows a mean clockwise vertical axis rotation of 34?? ?? 13??, group 2 consists of samples from rocks deposited be-tween 30 and 24 Ma and shows a mean clockwise rotation of 17?? ?? 11??, and group 3 consists of samples from rocks between 24 and 16 Ma and shows a mean clockwise rotation of 20?? ?? 12??. Although these three values of rotation are statistically indistinguishable at the 95% confidence level, we interpret them in combination with other data to indicate differential rotation across the St. Helens seismic zone (SHZ). The available paleomagnetic data for Eocene-Oligocene rocks west of the seismic zone show clockwise vertical axis rotations of 30?? ?? 8?? and 35?? ?? 9?? consistent with the value for group 1. The rotational values for groups 2 and 3 and the intrusive suite of Kidd Creek (13 Ma), despite their different ages, have similar values east of the SHZ. Comparing these groups of data east and west of the seismic zone indicates a differential rotation of 10?? ?? 3?? across it. In addition, the rates of rotation in southern Washington are similar to those for rocks in the western Cascades of Oregon and indicate that rotational deformation of Miocene age extends northward into southern Washington and eastward into the axis of the arc.

  17. Coastal lake sediments from the southern Cape, South Africa - Implications for sea level and climate variations during the Holocene

    NASA Astrophysics Data System (ADS)

    Wündsch, M.; Haberzettl, T.; Kirsten, K. L.; Meschner, S.; Frenzel, P.; Baade, J.; Daut, G.; Mäusbacher, R.; Kasper, T.; Quick, L. J.; Meadows, M. E.; Zabel, M.

    2015-12-01

    Within the RAIN project (Regional Archives for Integrated iNvestigations) interdisciplinary investigations on climate evolution and environmental change in southern Africa during the Late Quaternary are being conducted. For this purpose, spatial and temporal variations of the three major rainfall zones covering South Africa (winter-, summer- and year-round rainfall zone) are studied using both marine and terrestrial archives. Here we present results inferred from sediment records from lakes Groenvlei and Eilandvlei located on the southern Cape coast within the year-round rainfall zone. From Eilandvlei, a brackish lake that is connected to the Indian Ocean via an estuary, a 30.5 m sediment core was recovered. Reservoir-corrected radiocarbon ages reveal a continuous sedimentation and a maximum age of about 8,900 cal BP. This ultra-high-resolution record of environmental change during the Holocene represents a unique discovery for entire southern Africa. Geochemical data reveal different phases of marine and terrestrial sediment deposition throughout the covered time span. Hence, this record reflects changes in sea level, but also variations in terrestrial sediment transport and thus changing climatic conditions. The sediment core from Groenvlei, which today is isolated from the Indian Ocean, covers the past 4,200 cal BP. Sediments from this lake are predominantly composed of autochthonous carbonates. Mineralogical investigations reveal alternating deposition of calcite and aragonite/dolomite, pointing to variable Mg/Ca ratios and thus variations in lake water salinity. These changes can be linked to sea level variations as well as to changes in the precipitation/evaporation balance, and hence climate. Based on these results, the Groenvlei record reveals a decreasing marine influence and a trend from generally drier to wetter conditions within the last 4,200 yrs. Moreover, several layers of enhanced allochtonous input were detected in this record, which can be

  18. The discovery of new deep-sea hydrothermal vent communities in the southern ocean and implications for biogeography.

    PubMed

    Rogers, Alex D; Tyler, Paul A; Connelly, Douglas P; Copley, Jon T; James, Rachael; Larter, Robert D; Linse, Katrin; Mills, Rachel A; Garabato, Alfredo Naveira; Pancost, Richard D; Pearce, David A; Polunin, Nicholas V C; German, Christopher R; Shank, Timothy; Boersch-Supan, Philipp H; Alker, Belinda J; Aquilina, Alfred; Bennett, Sarah A; Clarke, Andrew; Dinley, Robert J J; Graham, Alastair G C; Green, Darryl R H; Hawkes, Jeffrey A; Hepburn, Laura; Hilario, Ana; Huvenne, Veerle A I; Marsh, Leigh; Ramirez-Llodra, Eva; Reid, William D K; Roterman, Christopher N; Sweeting, Christopher J; Thatje, Sven; Zwirglmaier, Katrin

    2012-01-01

    Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than

  19. Os, Sr, Nd, and Pb isotope systematics of southern African peridotite xenoliths - Implications for the chemical evolution of subcontinental mantle

    NASA Technical Reports Server (NTRS)

    Walker, R. J.; Carlson, R. W.; Shirey, S. B.; Boyd, F. R.

    1989-01-01

    Isotope analyses of Os, Sr, Nd, and Pb elements were caried out on twelve peridotite xenoliths from the Jagersfontein, Letseng-la-terae, Thaba Patsoa, Mothae, and Premier kimberlites of southern Africa, to investigate the timing and the nature of melt extraction from the continental lithosphere and its relation to the continent formation and stabilization. The distinct Os and Pb isotopic characteristics found in these samples suggested that both the low- and the high-temperature peridotites reside in an ancient stable lithospheric 'keel' to the craton that has been isolated from chemical exchange with the sublithospheric mantle for time periods in excess of 2 Ga.

  20. Thrust faults of southern Diamond Mountains, central Nevada: Implications for hydrocarbons in Diamond Valley and at Yucca Mountain

    SciTech Connect

    French, D.E.

    1993-04-01

    Overmature Mississippian hydrocarbon source rocks in the southern Diamond Mountains have been interpreted to be a klippe overlying less mature source rocks and represented as an analogy to similar conditions near Yucca Mountain (Chamberlain, 1991). Geologic evidence indicates an alternative interpretation. Paleogeologic mapping indicates the presence of a thrust fault, referred to here as the Moritz Nager Thrust Fault, with Devonian rocks emplaced over Permian to Mississippian strata folded into an upright to overturned syncline, and that the overmature rocks of the Diamond Mountains are in the footwall of this thrust. The upper plate has been eroded from most of the Diamond Mountains but remnants are present at the head of Moritz Nager Canyon and at Sentinel Mountain. Devonian rocks of the upper plate comprised the earliest landslide megabreccia. Later, megabreccias of Pennsylvanian and Permian rocks of the overturned syncline of the lower plate were deposited. By this interpretation the maturity of lower-plate source rocks in the southern Diamond Mountains, which have been increased by tectonic burial, is not indicative of conditions in Diamond Valley, adjacent to the west, where upper-plate source rocks might be present in generating conditions. The interpretation that overmature source rocks of the Diamond Mountains are in a lower plate rather than in a klippe means that this area is an inappropriate model for the Eleana Range near Yucca Mountain.

  1. A comparison of observed and modeled surface waves in southern Lake Michigan and the implications for models of sediment resuspension.

    SciTech Connect

    Hawley, N.; Lesht, B. M.; Schwab, D. J.; Environmental Research; Great Lakes Environmental Research Lab

    2004-06-25

    Subsurface pressure sensors were used to make measurements of surface waves during 18 deployments in southern Lake Michigan between 1998 and 2000. Most of the observations were made during the unstratified period (November--May) in water depths between 10 and 55 m. The observations (as well as those obtained from the National Data Buoy Center (NDBC) buoy 45007, which is located in the middle of the southern basin of the lake) were compared to the results obtained from the Great Lakes Environmental Research Laboratory (GLERL)-Donelan wave model implemented on a 2-km grid. The results show that the wave model does a good job of calculating the wave heights, but consistently underestimates the wave periods. In over 80% of the cases the bottom stresses calculated from both the observations and the wave model results agree as to whether or not resuspension occurs, but over 70% of this agreement is for cases when resuspension does not occur; both stresses predict resuspension about 6% of the time. Since the bottom stresses calculated from the model results are usually lower than those calculated from the observations, resuspension estimates based on the wave model parameters are also lower than those calculated from the observed waves.

  2. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals.

    PubMed

    Will, Manuel; Mackay, Alex; Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable. PMID:26125972

  3. Provenance and tectonic implications of heavy minerals in Pliocene-Pleistocene siliciclastic sediments of the southern Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Acquafredda, P.; Fornelli, A.; Piccarreta, G.; Summa, V.

    1997-10-01

    During the late Tortonian-Pleistocene, rifting in the Tyrrhenian region and compression in the Apennines coexisted, with an eastward migration of the rift basin-thrust belt-foredeep systems. In a northwest-southeast area of the southern Apennine Pliocene deposits, accumulated in piggy-back basins, and Pliocene-Pleistocene sediments deposited in the foredeep basins, are contiguous. Here our attention is focused on the heavy minerals, which are sensitive indicators of source rocks. Garnet, blue amphibole, staurolite, clinopyroxene, epidote have been analysed and compared with the minerals of the likely protoliths. Blue amphibole and staurolite derive from Early Miocene 'Tufiti di Tusa e Arenarie di Corleto' Formation; pyroxenes derive from Pleistocene Vulture volcanics and, possibly from Pliocene volcaniclastic strata cropping out in Basilicata. Interestingly, blue amphibole and staurolite, present in the Early Miocene volcanolithic and quartzofeldspathic sandstones of the 'Tufiti di Tusa e Arenarie di Corleto' Formation, are absent in Tortonian siliciclastic strata, but appear again in Pliocene-Pleistocene siliciclastic sediments. The space-time distribution of these minerals was controlled by important morphostructural modifications affecting the southern Apennine thrust belt.

  4. Late Pleistocene and Holocene uplift history of Cyprus: implications for active tectonics along the southern margin of the Anatolian microplate

    USGS Publications Warehouse

    Harrison, R.W.; Tsiolakis, E.; Stone, B.D.; Lord, A.; McGeehin, J.P.; Mahan, S.A.; Chirico, P.

    2013-01-01

    The nature of the southern margin of the Anatolian microplate during the Neogene is complex, controversial and fundamental in understanding active plate-margin tectonics and natural hazards in the Eastern Mediterranean region. Our investigation provides new insights into the Late Pleistocene uplift history of Cyprus and the Troodos Ophiolite. We provide isotopic (14C) and radiogenic (luminescence) dates of outcropping marine sediments in eastern Cyprus that identify periods of deposition during marine isotope stages (MIS) 3, 4, 5 and 6. Past sea-levels indicated by these deposits are c. 95±25 m higher in elevation than estimates of worldwide eustatic sea-level. An uplift rate of c. 1.8 mm/year and possibly as much as c. 4.1 mm/year in the past c. 26–40 ka is indicated. Holocene marine deposits also occur at elevations higher than those expected for past SL and suggest uplift rates of c. 1.2–2.1 mm/year. MIS-3 marine deposits that crop out in southern and western Cyprus indicate uniform island-wide uplift. We propose a model of tectonic wedging at a plate-bounding restraining bend as a mechanism for Late Pleistocene to Holocene uplift of Cyprus; uplift is accommodated by deformation and seismicity along the margins of the Troodos Ophiolite and re-activation of its low-angle, basal shear zone.

  5. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals

    PubMed Central

    Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable. PMID:26125972

  6. Variability in transport pathways on and around the South Georgia shelf, Southern Ocean: Implications for recruitment and retention

    NASA Astrophysics Data System (ADS)

    Young, Emma F.; Thorpe, Sally E.; Banglawala, Neelofer; Murphy, Eugene J.

    2014-01-01

    The waters around South Georgia are among the most productive in the Southern Ocean, with zooplankton populations close to the island, in particular Antarctic krill, supporting vast colonies of higher predators. However, our understanding of the processes governing variability in the supply of these food resources is limited by the poor spatial and temporal resolution of available data. Here, we use a numerical modeling approach to examine the underlying physical processes driving the recruitment and retention of zooplankton to the South Georgia shelf. Variability in the magnitude and spatial distribution of recruitment was dominated by the proximity and orientation of the southern Antarctic Circumpolar Current front to the shelf edge. Shelf retention was highest for source sites on the southwest shelf, with the main transport routes off the shelf to the north and northwest. Retention was lowest in the austral summer and winter; in summer increased glacial melt drives stronger off-shelf near-surface currents, while in winter, stronger winds lead to an increase in off-shelf transport. Of particular note was the prediction of a significant increase in retention for particles released throughout the shelf in April and July 2000. This period coincided with the development of pronounced anticlockwise shelf flows, associated with horizontal density gradients due to reduced wind mixing of shelf waters, and differences between shelf and oceanic waters, which significantly reduced off-shelf transport rates. Such findings are crucial for understanding the influence of variability in physical processes on the ecosystem at South Georgia.

  7. Overcoming Structural Adjustment Policies in Africa: Strategies for Vocational Education and Training in the Sudan.

    ERIC Educational Resources Information Center

    Washi, Sidiga; Pitamber, Sunita

    Most developing countries have been debt ridden since the mid-1970s. This continuing debt burden has resulted in increasing prices and inflation, growing unemployment, and daily life difficulties. This problem has been acute for the Sudan. Sudan received help from the International Monetary Fund (IMF) in 1978 and negotiated new credit terms. By…

  8. Upconversion nanosensor for sensitive fluorescence detection of Sudan I-IV based on inner filter effect.

    PubMed

    Fang, Aijin; Long, Qian; Wu, Qiongqiong; Li, Haitao; Zhang, Youyu; Yao, Shouzhuo

    2016-01-01

    Sudan dyes are banned as food additives due to the carcinogenicity of their metabolites in the human body. Therefore, it is of great significance for sensitive detection of Sudan dyes. This paper reports a novel nanosensor for Sudan dyes detection based on fluorescence (FL) quenching of hexadecyl trimethyl ammonium bromide (CTAB) stabilized upconversion nanoparticles (UCNPs) through the inner filter effect (IFE). In the presence of Sudan I-IV, the fluorescence emission of UCNPs was effectively quenched due to the absorption bands of Sudan I-IV largely covered the emission bands of UCNPs. Under the optimized conditions, the FL was quenched with Sudan concentration over the range of 0.05-40, 0.01-20, 0.01-40 and 0.05-40 μg/mL for Sudan I-IV, respectively. The corresponding limit of detection is 15.1, 2.83, 3.52 and 16.7 ng/mL (at 3σ/slope) respectively. Meanwhile, the nanosensor shows good selectivity, sensitivity and can be successfully applied to detection of Sudan in chili powder samples. PMID:26653433

  9. The Lost Boys of Sudan: Ambiguous Loss, Search for Family, and Reestablishing Relationships with Family Members

    ERIC Educational Resources Information Center

    Luster, Tom; Qin, Desiree B.; Bates, Laura; Johnson, Deborah J.; Rana, Meenal

    2008-01-01

    The "Lost Boys of Sudan" were separated from their families by civil war and subsequently lived in 3 other countries--Ethiopia, Kenya, and the United States. In-depth interviews were conducted with 10 refugees who located surviving family members in Sudan after an average separation of 13.7 years. The interviews probed their experiences of…

  10. Games, Social Simulations, and Data--Integration for Policy Decisions: The "Sudan" Game

    ERIC Educational Resources Information Center

    Landwehr, Peter; Spraragen, Marc; Ranganathan, Balki; Carley, Kathleen M.; Zyda, Michael

    2013-01-01

    In this article, the authors discuss the development of the "Sudan Game," an interactive model of the country in the time period leading up to the Sudanese referendum on the secession of the South. While many simulations are designed to educate about their subjects, the "Sudan Game" is intended to be a prototype for policy making via gameplay. It…

  11. The Birth of a Nation Is Only the Beginning: The Travails of South Sudan

    ERIC Educational Resources Information Center

    Totten, Samuel

    2014-01-01

    Just three years since it broke away from Sudan, the new country of South Sudan is embroiled in a violent civil war. This article examines what went wrong and why, by discussing the incredible difficulty of building a new nation from scratch following years of conflict, war, suspicion, and great expectations. How this tragedy will end is…

  12. Upconversion nanosensor for sensitive fluorescence detection of Sudan I-IV based on inner filter effect.

    PubMed

    Fang, Aijin; Long, Qian; Wu, Qiongqiong; Li, Haitao; Zhang, Youyu; Yao, Shouzhuo

    2016-01-01

    Sudan dyes are banned as food additives due to the carcinogenicity of their metabolites in the human body. Therefore, it is of great significance for sensitive detection of Sudan dyes. This paper reports a novel nanosensor for Sudan dyes detection based on fluorescence (FL) quenching of hexadecyl trimethyl ammonium bromide (CTAB) stabilized upconversion nanoparticles (UCNPs) through the inner filter effect (IFE). In the presence of Sudan I-IV, the fluorescence emission of UCNPs was effectively quenched due to the absorption bands of Sudan I-IV largely covered the emission bands of UCNPs. Under the optimized conditions, the FL was quenched with Sudan concentration over the range of 0.05-40, 0.01-20, 0.01-40 and 0.05-40 μg/mL for Sudan I-IV, respectively. The corresponding limit of detection is 15.1, 2.83, 3.52 and 16.7 ng/mL (at 3σ/slope) respectively. Meanwhile, the nanosensor shows good selectivity, sensitivity and can be successfully applied to detection of Sudan in chili powder samples.

  13. Current situation of Peste des petits ruminants (PPR) in the Sudan.

    PubMed

    Saeed, Intisar K; Ali, Yahia H; Khalafalla, AbdelMelik I; Rahman-Mahasin, E A

    2010-01-01

    The current situation of PPR in Sudan was investigated. A total of 61 tissue samples were collected from various PPR suspected outbreaks in sheep in Sudan during 2008. Collected tissue samples were tested for PPR antigen using IcELISA, PPR antigen was detected in 26 out of 61 samples (42.6%). Highest antigen detection rate was in specimens collected from western Sudan. A total of 1198 serum samples were collected from sheep (n = 500), camels (n = 392), and goats (n = 306) from different areas in Sudan (Khartoum, Gezira, Tambool, River Nile, Kordofan, White Nile, Blue Nile, Gedarif, Kassala, Halfa ElGadida, Port Sudan). Collected sera were examined for PPR antibodies using cELISA, a total of 336 (67.2%) sheep, 170 (55.6%) goat and 1 (0.3%) camel samples were found to be positive.

  14. Focal mechanisms in the southern Aegean from temporary seismic networks - implications for the regional stress field and ongoing deformation processes

    NASA Astrophysics Data System (ADS)

    Friederich, W.; Brüstle, A.; Küperkoch, L.; Meier, T.; Lamara, S.; Egelados Working Group

    2014-05-01

    The lateral variation of the stress field in the southern Aegean plate and the subducting Hellenic slab is determined from recordings of seismicity obtained with the CYCNET and EGELADOS networks in the years from 2002 to 2007. First motions from 7000 well-located microearthquakes were analysed to produce 540 well-constrained focal mechanisms. They were complemented by another 140 derived by waveform matching of records from larger events. Most of these earthquakes fall into 16 distinct spatial clusters distributed over the southern Aegean region. For each cluster, a stress inversion could be carried out yielding consistent estimates of the stress field and its spatial variation. At crustal levels, the stress field is generally dominated by a steeply dipping compressional principal stress direction except in places where coupling of the subducting slab and overlying plate come into play. Tensional principal stresses are generally subhorizontal. Just behind the forearc, the crust is under arc-parallel tension whereas in the volcanic areas around Kos, Columbo and Astypalea tensional and intermediate stresses are nearly degenerate. Further west and north, in the Santorini-Amorgos graben and in the area of the islands of Mykonos, Andros and Tinos, tensional stresses are significant and point around the NW-SE direction. Very similar stress fields are observed in western Turkey with the tensional axis rotated to NNE-SSW. Intermediate-depth earthquakes below 100 km in the Nisyros region indicate that the Hellenic slab experiences slab-parallel tension at these depths. The direction of tension is close to east-west and thus deviates from the local NW-oriented slab dip presumably owing to the segmentation of the slab. Beneath the Cretan sea, at shallower levels, the slab is under NW-SE compression. Tensional principal stresses in the crust exhibit very good alignment with extensional strain rate principal axes derived from GPS velocities except in volcanic areas, where both

  15. Glacial geomorphology of the Torres del Paine region (southern Patagonia): Implications for glaciation, deglaciation and paleolake history

    NASA Astrophysics Data System (ADS)

    García, Juan-Luis; Hall, Brenda L.; Kaplan, Michael R.; Vega, Rodrigo M.; Strelin, Jorge A.

    2014-01-01

    The processes affecting paleoclimate variability and Pleistocene glacial landscape development in the southern mid-latitudes remain poorly understood, in part because of the scarcity of comprehensive, well-studied records. Glacial landforms are invaluable for reconstructing past ice-sheet, climate, and associated environmental changes along the southern Andes, but there are significant spatial and temporal gaps in existing data. In this paper, we present new geomorphic and sedimentologic analyses, including surficial maps, for the Torres del Paine region (51°S, 73°W), southern South America. Our findings provide a new framework for understanding changes in the regional glacier history and Pleistocene landscape development. Glacial extent during the local last glacial maximum (LGM) remains unknown but new chronological data supported by geomorphic evidence afford evidence for a larger ice sheet at Torres del Paine than previously assumed. Deglaciation from the local LGM was underway by 17,400 ± 200 (1σ) cal. yr. BP. As opposed to previous suggestions, we have found that most of the moraines fringing the lakes in the Torres del Paine national park were deposited during a late-glacial expansion that occurred between 14,100 and 12,500 cal. yr. BP. Late-glacial advances also have been documented recently for the Última Esperanza and Lago Argentino basins to the south and north of Torres del Paine, respectively, suggesting an overall regional ice response to a climate signal. The Tehuelche paleolake accompanied each of the ice-sheet fluctuations in Torres del Paine. New data document at least three main phases of this paleolake, which drained eastward to the Atlantic Ocean, while the Andes gaps were blocked with ice. During the late phase of glacial lake formation, when water levels reached 125-155 m a.s.l., the lake likely merged with paleolake Consuelo in the Última Esperanza area at the end of the last glaciation. Lake Tehuelche in Torres del Paine had drained

  16. Evidence for and implications of sedimentary diapirism and mud volcanism in the southern Utopia highland-lowland boundary plain, Mars

    USGS Publications Warehouse

    Skinner, J.A.; Tanaka, K.L.

    2007-01-01

    Several types of spatially associated landforms in the southern Utopia Planitia highland-lowland boundary (HLB) plain appear to have resulted from localized geologic activity, including (1) fractured rises, (2) elliptical mounds, (3) pitted cones with emanating lobate materials, and (4) isolated and coalesced cavi (depressions). Stratigraphic analysis indicates these features are Hesperian or younger and may be associated with resurfacing that preferentially destroyed smaller (< 8 ?? km diameter) impact craters. Based on landform geomorphologies and spatial distributions, the documented features do not appear to be specifically related to igneous or periglacial processes or the back-wasting and erosion of the HLB scarp. We propose that these features are genetically related to and formed by sedimentary (mud) diapirs that ascended from zones of regionally confined, poorly consolidated, and mechanically weak material. We note morphologic similarities between the mounds and pitted cones of the southern Utopia boundary plain and terrestrial mud volcanoes in the Absheron Peninsula, Azerbaijan. These analogs provide a context for understanding the geological environments and processes that supported mud diapir-related modification of the HLB. In southern Utopia, mud diapirs near the Elysium volcanic edifice may have resulted in laccolith-like intrusions that produced the fractured rises, while in the central boundary plain mud diapirs could have extruded to form pitted cones, mounds, and lobate flows, perhaps related to compressional stresses that account for wrinkle ridges. The removal of material a few kilometers deep by diapiric processes may have resulted in subsidence and deformation of surface materials to form widespread cavi. Collectively, these inferences suggest that sedimentary diapirism and mud volcanism as well as related surface deformations could have been the dominant Hesperian mechanisms that altered the regional boundary plain. We discuss a model in

  17. Kinematics and age of Early Tertiary trench parallel volcano-tectonic lineaments in southern Mexico: Tectonic implications

    NASA Astrophysics Data System (ADS)

    Martini, M.; Ferrari, L.; Lopez Martinez, M.; Cerca Martinez, M.; Serrano Duran, L.

    2007-05-01

    We present new geological, structural, and geochronological data that constrain the timing and geometry of Early Tertiary strike slip deformation in southwestern Mexico and its relation with the concurrent magmatic activity. Geologic mapping in Guerrero and Michoacan States documented two regional WNW trending volcano-tectonic lineaments sub parallel to the present trench. The southernmost lineament runs for ~140 km from San Miguel Totolapan area (NW Guerrero) to Sanchiqueo (SE Michoacan), and passes through Ciudad Altamirano. Its southeastern part is marked by the alignment of at least eleven silicic to intermediate major domes as well as by the course of the Balsas River. The northwestern part of the lineament is characterized by ductile left lateral shear zones in Early Tertiary plutonic rocks observed in the Rio Chiquito valley. Domes near Ciudad Altamirano are unaffected by ductile shearing and yielded a ~42 Ma 40Ar/39Ar age, setting a minimum age for this deformation. The northern volcano-tectonic lineament runs for ~190 km between the areas of Huitzuco in northern Guerrero and the southern part of the Tzitzio fold in eastern Michoacan. The Huautla, Tilzapotla, Taxco, La Goleta and Nanchititla silicic centers (all in the range 37-34 Ma) are emplaced along this lineament, which continues to the WNW trough a mafic dike swarm exposed north of Tiquicheo (37-35 Ma) and the Purungueo subvolcanic body (~42 Ma). These rocks, unaffected by ductile shearing, give a minimum age of deformation similar to the southern Totolapan-Sanquicheo lineament. Post ~42 Ma deformation is essentially brittle and is characterized by several left lateral and right lateral transcurrent faults with typical Riedel patterns. Other trench-parallel left lateral shear zones active in pre-Oligocene times were recently reported in western Oaxaca. The recognizing of Early Tertiary trench-parallel and left-lateral ductile shearing in internal areas of southern Mexico suggest a field of widely

  18. Analysis of energy-saving potential in residential buildings in Xiamen City and its policy implications for southern China

    NASA Astrophysics Data System (ADS)

    Guo, Fei

    The buildings sector is the largest energy-consuming sector in the world. Residential buildings consume about three-quarters of the final energy in the buildings sector. Promoting residential energy savings is in consequence critical for addressing many energy-use-related environmental challenges, such as climate change and air pollution. Given China's robust economic growth and fast urbanization, it is now a critical time to develop policy interventions on residential energy use in the nation. With this as a background, this dissertation explores effective policy intervention opportunities in southern China through analyzing the residential energy-saving potential, using the city of Xiamen as a case study. Four types of residential energy-saving potential are analyzed: technical potential, economic potential, maximum achievable potential (MAP), and possible achievable potential (PAP). Of these, the first two types are characterized as static theoretical evaluation, while the last two represent dynamic evaluation within a certain time horizon. The achievable potential analyses are rarely seen in existing literature. The analytical results reveal that there exists a significant technical potential for residential energy savings of about 20.9-24.9% in the city of Xiamen. Of the technical potential, about two-thirds to four-fifths are cost-effective from the government or society perspective. The cost-effectiveness is evaluated by comparing the "Levelized Cost of Conserved Energy (LCOCE)" of available advanced technical measures with the "Actual Cost" of conserved energy. The "Actual Cost" of energy is defined by adding the environmental externalities costs and hidden government subsidies over the retail prices of energy. The achievable potential analyses are particularly based on two key realistic factors: 1) the gradual ramping-up adoption process of advanced technical measures; and 2) individuals' adoption-decision making on them. For implementing the achievable

  19. Origin of REE-rich ferrocarbonatites in southern Siberia (Russia): implications based on melt and fluid inclusions

    NASA Astrophysics Data System (ADS)

    Prokopyev, Ilya R.; Borisenko, Alexander S.; Borovikov, Andrey A.; Pavlova, Galina G.

    2016-06-01

    Fe-rich carbonatites with a mineral assemblage of ankerite-calcite or siderite are widespread in southern Siberia, Russia. The siderite carbonatites are associated with F-Ba-Sr-REE mineralization and have a 40Ar/39Ar age of 117.2 ± 1.3 Ma. Melt and fluid inclusions suggest that the carbonatites formed from volatile-rich alkali- and chloride-bearing carbonate melts. Ankerite-calcite carbonatites formed from carbonatite melt at a temperature of more than 790 °C. The ferrocarbonatites (the second phase of carbonatite intrusion) formed from a sulfate-carbonate-chloride fluid phase (brine-melt) at >650 °C and ≥360 MPa. The brine-melt fluid phase had high concentrations of Fe and LREEs. A subsequent hydrothermal overprint contributed to the formation of economically important barite-Sr-fluorite-REE mineralization in polymict siderite breccia.

  20. Historical land-use and landscape change in southern Sweden and implications for present and future biodiversity

    PubMed Central

    Cui, Qiao-Yu; Gaillard, Marie-José; Lemdahl, Geoffrey; Stenberg, Li; Sugita, Shinya; Zernova, Ganna

    2014-01-01

    The two major aims of this study are (1) To test the performance of the Landscape Reconstruction Algorithm (LRA) to quantify past landscape changes using historical maps and related written sources, and (2) to use the LRA and map reconstructions for a better understanding of the origin of landscape diversity and the recent loss of species diversity. Southern Sweden, hemiboreal vegetation zone. The LRA was applied on pollen records from three small bogs for four time windows between AD 1700 and 2010. The LRA estimates of % cover for woodland/forest, grassland, wetland, and cultivated land were compared with those extracted from historical maps within 3-km radius around each bog. Map-extracted land-use categories and pollen-based LRA estimates (in % cover) of the same land-use categories show a reasonable agreement in several cases; when they do not agree, the assumptions used in the data (maps)-model (LRA) comparison are a better explanation of the discrepancies between the two than possible biases of the LRA modeling approach. Both the LRA reconstructions and the historical maps reveal between-site differences in landscape characteristics through time, but they demonstrate comparable, profound transformations of the regional and local landscapes over time and space due to the agrarian reforms in southern Sweden during the 18th and 19th centuries. The LRA was found to be the most reasonable approach so far to reconstruct quantitatively past landscape changes from fossil pollen data. The existing landscape diversity in the region at the beginning of the 18th century had its origin in the long-term regional and local vegetation and land-use history over millennia. Agrarian reforms since the 18th century resulted in a dramatic loss of landscape diversity and evenness in both time and space over the last two centuries leading to a similarly dramatic loss of species (e.g., beetles). PMID:25478148

  1. Implications of water supply for indigenous Americans during Holocene ardity phases on the Southern High Plains, USA

    USGS Publications Warehouse

    Wood, W.W.; Stokes, S.; Rich, J.

    2002-01-01

    Springs in the 40 to 50 large lake basins (>15 km2) on the southern portion of the Southern High Plains (SHP) were active during periods of aridity in the Holocene when there may have been human habitation of the area. Eolian erosion of the lake floors and lunette accretion occurred as groundwater levels declined in response to decreased groundwater recharge. The declining lake floor associated with eolian erosion allowed groundwater evaporative discharge to continue, thus maintaining a groundwater gradient toward the lake. This hydrologic condition was favorable for a relatively continuous spring discharge to the lake, independent of the elevation of the lake floor. To evaluate the postulated dynamic equilibrium critical to this conclusion, 17 optically stimulated ages were determined from a 17.7-m deep core of a lunette adjacent to Double Lakes, Texas (33??13???15???N, 101??54???08???W). The core yielded sediment accumulation dates of 11,500 ?? 1100, 6500 ?? 700, and 4900 ?? 500 yr B.P., corresponding broadly with periods of aridity known from other evidence. Based on analysis of this lunette, it is concluded that springs in Double Lakes basin probably existed throughout the Holocene with discharges similar to those observed historically. We assumed that similar dynamic equilibrium existed in the other large lake basins in the SHP and that these springs could have provided a continuous source of water for indigenous peoples during periods of prolonged aridity. The dynamic equilibrium that is proposed in this study is applicable not only to other arid and semiarid geographic areas with wind-erodible material but also over different geologic times. ?? 2002 University of Washington.

  2. Reproductive biology and implications for management of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf.

    PubMed

    Grandcourt, E M; Al Abdessalaam, T Z; Francis, F; Al Shamsi, A T

    2010-12-01

    The reproductive biology of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf was determined from the examination of 781 individuals collected between September 2008 and August 2009. There was no histological evidence of adult sex change, and sex ratios did not differ significantly from unity across all size and age classes. Testes had an ovarian structure and a remnant lumen which was not used for sperm transport; furthermore, residual oocytes were observed in the testes of some immature, resting and developing males. A dramatic change in the sex ratio of the smallest and youngest size and age classes suggested that juvenile female to male sex change occurred between 21·0 cm fork length (L(F)) and 24·0 cm L(F) at 1 year of age. The combination of histological evidence with the sexual composition of the size and age structures suggests a non-functional protogynous hermaphroditic sexual pattern, which is analogous to functional gonochorism. The spawning season was well defined, occurring once a year during March, April and early May. Peaks in spawning occurred after full moons, there was a cessation in spawning activity after new moons and spawning was completed within three lunar cycles. The distribution of males over the entire size and age ranges and the absence of inactive mature females during the spawning season suggested that the population was not constrained by sperm limitation. Size-specific and age-specific reproductive potential indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of L. nebulosus. The maximum recorded age (11 years), small mean size and young age at sexual maturation (L(m50) = 26·7 cm L(F), 2·1 years, for females and 19·4 cm L(F), 0·5 years, for males) may be a direct result of intensive demersal fishing in the southern Arabian Gulf. PMID:21155780

  3. Determinants of Persistence and Tolerance of Carnivores on Namibian Ranches: Implications for Conservation on Southern African Private Lands

    PubMed Central

    Lindsey, Peter Andrew; Havemann, Carl Peter; Lines, Robin; Palazy, Lucille; Price, Aaron Ernest; Retief, Tarryn Anne; Rhebergen, Tiemen; Van der Waal, Cornelis

    2013-01-01

    Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where

  4. Peleolakes and impact basins in southern Arabia Terra, including Meridiani Planum: Implications for the formation of hematite deposits on Mars

    USGS Publications Warehouse

    Newsom, Horton E.; Barber, C.A.; Hare, T.M.; Schelble, R.T.; Sutherland, V.A.; Feldman, W.C.

    2003-01-01

    The hematite deposit in Meridiani Planum was selected for a Mars Exploration Rover (MER) landing site because water could be involved in the formation of hematite, and water is a key ingredient in the search for life. Our discovery of a chain of paleolake basins and channels along the southern margin of the hematite deposits in Meridiani Planum with the presence of the strongest hematite signature adjacent to a paleolake basin, supports the possible role of water in the formation of the hematite and the deposition of other layered materials in the region. The hematite may have formed by direct precipitation from lake water, as coatings precipitated from groundwater, or by oxidation of preexisting iron oxide minerals. The paleolake basins were fed by an extensive channel system, originating from an area larger than Texas and located south of the Schiaparelli impact basin. On the basis of stratigraphic relationships, the formation of channels in the region occurred over much of Mars' history, from before the layered materials in Meridiani Planum were deposited until recently. The location of the paleolake basins and channels is connected with the impact cratering history of the region. The earliest structure identified in this study is an ancient circular multiringed basin (800-1600 km diameter) that underlies the entire Meridiani Planum region. The MER landing site is located on the buried northern rim of a later 150 km diameter crater. This crater is partially filled with layered deposits that contained a paleolake in its southern portion. Copyright 2003 by the American Geophysical Union.

  5. Increased dry-season length over southern Amazonia in recent decades and its implication for future climate projection

    PubMed Central

    Fu, Rong; Yin, Lei; Li, Wenhong; Arias, Paola A.; Dickinson, Robert E.; Huang, Lei; Chakraborty, Sudip; Fernandes, Katia; Liebmann, Brant; Fisher, Rosie; Myneni, Ranga B.

    2013-01-01

    We have observed that the dry-season length (DSL) has increased over southern Amazonia since 1979, primarily owing to a delay of its ending dates (dry-season end, DSE), and is accompanied by a prolonged fire season. A poleward shift of the subtropical jet over South America and an increase of local convective inhibition energy in austral winter (June–August) seem to cause the delay of the DSE in austral spring (September–November). These changes cannot be simply linked to the variability of the tropical Pacific and Atlantic Oceans. Although they show some resemblance to the effects of anthropogenic forcings reported in the literature, we cannot attribute them to this cause because of inadequate representation of these processes in the global climate models that were presented in the Intergovernmental Panel on Climate Change’s Fifth Assessment Report. These models significantly underestimate the variability of the DSE and DSL and their controlling processes. Such biases imply that the future change of the DSE and DSL may be underestimated by the climate projections provided by the Intergovernmental Panel on Climate Change’s Fifth Assessment Report models. Although it is not clear whether the observed increase of the DSL will continue in the future, were it to continue at half the rate of that observed, the long DSL and fire season that contributed to the 2005 drought would become the new norm by the late 21st century. The large uncertainty shown in this study highlights the need for a focused effort to better understand and simulate these changes over southern Amazonia. PMID:24145443

  6. Increased dry-season length over southern Amazonia in recent decades and its implication for future climate projection.

    PubMed

    Fu, Rong; Yin, Lei; Li, Wenhong; Arias, Paola A; Dickinson, Robert E; Huang, Lei; Chakraborty, Sudip; Fernandes, Katia; Liebmann, Brant; Fisher, Rosie; Myneni, Ranga B

    2013-11-01

    We have observed that the dry-season length (DSL) has increased over southern Amazonia since 1979, primarily owing to a delay of its ending dates (dry-season end, DSE), and is accompanied by a prolonged fire season. A poleward shift of the subtropical jet over South America and an increase of local convective inhibition energy in austral winter (June-August) seem to cause the delay of the DSE in austral spring (September-November). These changes cannot be simply linked to the variability of the tropical Pacific and Atlantic Oceans. Although they show some resemblance to the effects of anthropogenic forcings reported in the literature, we cannot attribute them to this cause because of inadequate representation of these processes in the global climate models that were presented in the Intergovernmental Panel on Climate Change's Fifth Assessment Report. These models significantly underestimate the variability of the DSE and DSL and their controlling processes. Such biases imply that the future change of the DSE and DSL may be underestimated by the climate projections provided by the Intergovernmental Panel on Climate Change's Fifth Assessment Report models. Although it is not clear whether the observed increase of the DSL will continue in the future, were it to continue at half the rate of that observed, the long DSL and fire season that contributed to the 2005 drought would become the new norm by the late 21st century. The large uncertainty shown in this study highlights the need for a focused effort to better understand and simulate these changes over southern Amazonia.

  7. Determinants of persistence and tolerance of carnivores on Namibian ranches: implications for conservation on Southern African private lands.

    PubMed

    Lindsey, Peter Andrew; Havemann, Carl Peter; Lines, Robin; Palazy, Lucille; Price, Aaron Ernest; Retief, Tarryn Anne; Rhebergen, Tiemen; Van der Waal, Cornelis

    2013-01-01

    Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where

  8. Increased dry-season length over southern Amazonia in recent decades and its implication for future climate projection.

    PubMed

    Fu, Rong; Yin, Lei; Li, Wenhong; Arias, Paola A; Dickinson, Robert E; Huang, Lei; Chakraborty, Sudip; Fernandes, Katia; Liebmann, Brant; Fisher, Rosie; Myneni, Ranga B

    2013-11-01

    We have observed that the dry-season length (DSL) has increased over southern Amazonia since 1979, primarily owing to a delay of its ending dates (dry-season end, DSE), and is accompanied by a prolonged fire season. A poleward shift of the subtropical jet over South America and an increase of local convective inhibition energy in austral winter (June-August) seem to cause the delay of the DSE in austral spring (September-November). These changes cannot be simply linked to the variability of the tropical Pacific and Atlantic Oceans. Although they show some resemblance to the effects of anthropogenic forcings reported in the literature, we cannot attribute them to this cause because of inadequate representation of these processes in the global climate models that were presented in the Intergovernmental Panel on Climate Change's Fifth Assessment Report. These models significantly underestimate the variability of the DSE and DSL and their controlling processes. Such biases imply that the future change of the DSE and DSL may be underestimated by the climate projections provided by the Intergovernmental Panel on Climate Change's Fifth Assessment Report models. Although it is not clear whether the observed increase of the DSL will continue in the future, were it to continue at half the rate of that observed, the long DSL and fire season that contributed to the 2005 drought would become the new norm by the late 21st century. The large uncertainty shown in this study highlights the need for a focused effort to better understand and simulate these changes over southern Amazonia. PMID:24145443

  9. Determinants of persistence and tolerance of carnivores on Namibian ranches: implications for conservation on Southern African private lands.

    PubMed

    Lindsey, Peter Andrew; Havemann, Carl Peter; Lines, Robin; Palazy, Lucille; Price, Aaron Ernest; Retief, Tarryn Anne; Rhebergen, Tiemen; Van der Waal, Cornelis

    2013-01-01

    Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where

  10. Historical land-use and landscape change in southern Sweden and implications for present and future biodiversity.

    PubMed

    Cui, Qiao-Yu; Gaillard, Marie-José; Lemdahl, Geoffrey; Stenberg, Li; Sugita, Shinya; Zernova, Ganna

    2014-09-01

    The two major aims of this study are (1) To test the performance of the Landscape Reconstruction Algorithm (LRA) to quantify past landscape changes using historical maps and related written sources, and (2) to use the LRA and map reconstructions for a better understanding of the origin of landscape diversity and the recent loss of species diversity. Southern Sweden, hemiboreal vegetation zone. The LRA was applied on pollen records from three small bogs for four time windows between AD 1700 and 2010. The LRA estimates of % cover for woodland/forest, grassland, wetland, and cultivated land were compared with those extracted from historical maps within 3-km radius around each bog. Map-extracted land-use categories and pollen-based LRA estimates (in % cover) of the same land-use categories show a reasonable agreement in several cases; when they do not agree, the assumptions used in the data (maps)-model (LRA) comparison are a better explanation of the discrepancies between the two than possible biases of the LRA modeling approach. Both the LRA reconstructions and the historical maps reveal between-site differences in landscape characteristics through time, but they demonstrate comparable, profound transformations of the regional and local landscapes over time and space due to the agrarian reforms in southern Sweden during the 18th and 19th centuries. The LRA was found to be the most reasonable approach so far to reconstruct quantitatively past landscape changes from fossil pollen data. The existing landscape diversity in the region at the beginning of the 18th century had its origin in the long-term regional and local vegetation and land-use history over millennia. Agrarian reforms since the 18th century resulted in a dramatic loss of landscape diversity and evenness in both time and space over the last two centuries leading to a similarly dramatic loss of species (e.g., beetles). PMID:25478148

  11. The 1999 Mw 6.0 earthquake sequence in the southern Baikal rift, Asia, and its seismotectonic implications

    NASA Astrophysics Data System (ADS)

    Radziminovitch, Natalia; Déverchère, Jacques; Melnikova, Valentina; San'kov, Vladimir; Giljova, Nadezhda

    2005-05-01

    The 1999 February 25 earthquake (Mw= 6.0) is the largest event to have occurred in the Baikal rift system since the 1959 M= 6.8 earthquake. This earthquake sequence took place in the southern basin of Lake Baikal, a region characterized by a sharp transition from strike-slip faulting on the Main Sayan Fault to normal faulting along the border faults of the lake. Thanks to the development of the regional network and a temporal station installed after the main shock, we performed a relocation of the aftershocks to describe the rupture area and to determine fault-plane solutions. We show that the main shock was caused by normal faulting on an intrabasin fault striking northeast and steeply dipping to the northwest. Aftershock hypocentres did not cluster at the same depth but were spread from 5 to 25 km depth. Stress inversion carried out using focal mechanisms of the sequence reveals a radial extensive stress regime with a minimum principal stress axis σ3 (N155°E) slightly oblique to the regional stress field (N139°E), which depicts a stronger intermediate σ2-axis. This behaviour suggests transient stress perturbation induced by the main shock in the neighbouring zones of the rupture. Strain release deduced from GPS data and historical seismicity shows that within the southern tip of the Baikal rift basin, a significant stress release has occurred for at least two centuries, probably through active normal faulting shared among several faults, while the Main Sayan strike-slip fault further west was undergoing interseismic strain accumulation.

  12. Radiocarbon dating and paleoclimatic significance of subfossil Limicolaria in northwestern Sudan

    NASA Astrophysics Data System (ADS)

    Haynes, C. Vance; Mead, Albert R.

    1987-07-01

    The discovery, identification, and radiocarbon dating of the large achatinid land snail Limicolaria kambeul chudeaui at six places in northwestern Sudan, north of the 100-mm isohyet, provide convincing evidence that at least 300 mm annual rainfall existed there 6000 yr ago. Since then the rainfall north of ca. 20°N lat in the eastern Sahara has certainly been <300 mm and probably <200 mm. Accelerator mass spectrometry has allowed the organic fraction, presumably conchiolin, to be accurately radiocarbon dated whereas carbonate fractions are ca. 600 yr too old. Comparative studies show the subfossil form, L. k. chudeaui, to be the most primitive in its species complex and to occupy a narrow east-west belt across Africa north of 15°N and west of 35°E. The northern limit of living forms lies within the southern part of the Sahelian zone in forest or forest-savanna. They cannot live in open grassland. Therefore, the distribution of L. k. chudeaui marks the former northern position of this zone during the middle Holocene, indicating a latitudinal shift of at least 5° (500 km).

  13. Preliminary field trials of acrolein in the Sudan*

    PubMed Central

    Ferguson, Frederick F.; Dawood, Ismail K.; Blondeau, René

    1965-01-01

    Field trials of acrolein for the simultaneous control of aquatic weeds and snails were conducted in the Sudan. Phytotoxicity studies at 25 and 50 ppm showed minor or no damage to furrow-irrigated crops, but flood irrigation of vegetable seedlings at 15 ppm was toxic. Effective downstream carriage of acrolein was demonstrated for a distance of 1.6 km at a concentration of 25 ppm. Planorbid snails (Bulinus and Biomphalaria) were almost completely eliminated (98-99% kills). All submersed aquatic weeds were destroyed. PMID:14310912

  14. Evaluation of anisotropy in physical/mechanical properties of metabasalts from Gadag (Southern India) - implications for vein emplacement and gold mineralization

    NASA Astrophysics Data System (ADS)

    Satheesan Vishnu, C.; Mamtani, Manish A.

    2016-04-01

    . This anisotropy of strength is a proof of the difference in physical property of the metabasalts with respect to magnetic foliation. This is also manifested in the result of P-wave velocity measurements, which is lower perpendicular (˜5000 m/s) to foliation than parallel (˜5700 m/s) to it. These results imply that the foliation developed during D1/D2 regional deformation dilated during D3 and resulted in emplacement of quartz veins, some of which are gold bearing. References: Mondal, T.K., Mamtani, M.A. (2013). 3-D Mohr circle construction using vein orientation data from Gadag (southern India) - implications to recognize fluid pressure fluctuation. Journal of Structural Geology 56, 45-56. Mondal, T.K., Mamtani, M.A. (2014). Fabric analysis in massive rocks of the Gadag region (southern India) - implications to decipher time relationship between regional deformation and gold mineralization. Tectonophysics 629, 238-249. Vishnu, C.S., Mamtani, M.A., Basu, A. (2010). AMS, ultrasonic P-wave velocity and rock strength analysis in quartzites devoid of mesoscopic foliations - implications for rock mechanics studies. Tectonophysics 494, 191-200.

  15. First field identification of the Cuonadong dome in southern Tibet: implications for EW extension of the North Himalayan gneiss dome

    NASA Astrophysics Data System (ADS)

    Fu, Jiangang; Li, Guangming; Wang, Genhou; Huang, Yong; Zhang, Linkui; Dong, Suiliang; Liang, Wei

    2016-07-01

    The Cuonadong dome exposes in east-southern margin of the North Himalayan gneiss domes (NHGD), which is reported first time in this study. The Cuonadong dome is located at the southern part of the Zhaxikang ore concentration area, which is divided into three tectono-lithostratigraphic units by two curved faults around the dome geometry from upper to lower (or from outer to inner): the upper unit, middle unit and lower unit, and the outer fault is Nading fault, while the inner fault is Jisong fault. The Cuonadong dome is a magmatic orthogneiss and leucogranite mantled by orthogneiss and metasedimentary rocks, which in turn are overlain by Jurassic metasedimentary and sedimentary rocks. The grades of metamorphism and structural deformation increase towards the core, which is correspondence with the Ridang Formation low-metamorphic schist, tourmaline granitic-biotite gneiss, garnet-mica gneiss and mylonitic quartz-mica gneiss. The Cuonadong dome preserves evidences for four major deformational events: firstly top-to-S thrust (D1), early approximately N-S extensional deformation (D2), main approximately E-W extensional deformation (D3), and late collapse structural deformation (D4) around the core of the Cuonadong dome, which are consistent to three groups lineation: approximately N-S-trending lineation including L1 and L2, E-W trending L3, and L4 with plunging towards outside of the dome, respectively. The formation of the Cuonadong dome was probably resulted from the main E-W extensional deformation which is a result of eastward flow of middle or lower crust from beneath Tibet accommodated by northward oblique underthrusting of Indian crust beneath Tibet. The establishment of the Cuonadong dome enhanced the E-W extension of the NHGD, which is further divided into two structural dome zones according to the different extensional directions: approximately N-S extensional North Himalayan gneiss domes (NS-NHGD) and E-W extensional North Himalayan gneiss domes (EW

  16. Regional variations in the lead isotopic composition of galena from southern Korea with implications for the discrimination of lead provenance

    NASA Astrophysics Data System (ADS)

    Jeong, Youn-Joong; Cheong, Chang-sik; Shin, Dongbok; Lee, Kwang-Sik; Jo, Hui Je; Gautam, Mukesh Kumar; Lee, Insung

    2012-11-01

    This study presents a comprehensive database (n = 215) of lead isotopes in galena from the southern Korean peninsula using new and published data. Of the 69 metal mines examined, predominantly skarn- and hydrothermal-type Pb-Zn-Au-Ag-Cu deposits were observed and were associated with Mesozoic magmatic activities. Galena samples from each geotectonic unit showed discrete lead isotopic signatures. The Gyeongsang basin samples were characteristically unradiogenic and had restricted variations in lead isotopic composition (206Pb/204Pb = 18.16-18.59, 207Pb/204Pb = 15.48-15.64, 208Pb/204Pb = 37.87-38.77). Their 208Pb/204Pb range indicated an involvement of source materials less thorogenic than the associated granites. The galena samples from Cambro-Ordovician carbonate rocks of the northeastern Yeongnam massif and eastern Taebaeksan basin had the most radiogenic 206Pb/204Pb (19.28 ± 0.14) and 207Pb/204Pb (15.833 ± 0.027) ratios. Their lead isotopic trend indicated a combined contribution of ore lead from granitic magmas, Precambrian basements, and overlain host rocks. Less radiogenic galena samples from the middle to southwestern parts of the Yeongnam massif and Okcheon belt showed limited lead isotopic variations (206Pb/204Pb = 18.332 ± 0.065, 207Pb/204Pb = 15.693 ± 0.012, 208Pb/204Pb = 38.93 ± 0.07 on average), probably resulted from mixing with a common crustal basement. The differences in lead isotopes between the radiogenic and unradiogenic groups from the Yeongnam massif and Okcheon belt may reflect the spatial dissimilarity of involved crustal rocks. The old crust appears to have significantly contributed ore lead to galenas from the western Gyeonggi massif, but the geochronological meaning of their steep 207Pb/204Pb-206Pb/204Pb trend is not clear. The comprehensive database constructed by the present study suggests that lead province in the southern Korean peninsula may be subdivided into four discrete zones. Linear discriminant analysis showed that more

  17. Multi-decadal variability and trends in the El Niño-Southern Oscillation and tropical Pacific fisheries implications

    NASA Astrophysics Data System (ADS)

    Harrison, D. E.; Chiodi, Andrew M.

    2015-03-01

    Extremes of the El Niño-Southern Oscillation (ENSO) are known to have various socio-economic impacts, including effects on several Pacific fisheries. The 137-year-long record of Darwin sea-level pressure offers a uniquely long-term perspective on ENSO and provides important insight into various aspects of interannual to century-scale variability that affects these fisheries. One particular issue of interest is whether there is a centennial-scale (or longer) trend that can be expected to alter the future distributions of these fisheries. Since most tropical Pacific fishery records are no longer than a few decades, another issue is the extent to which trends over these recent decades are a good basis for detecting the presence of long-term (e.g., centennial-scale) deterministic changes, and perhaps thereby projecting future conditions. We find that the full 137-yr trend cannot be distinguished from zero with 95% confidence, and also that the ENSO variance in recent decades is very similar to that of the early decades of the record, suggesting that ENSO has not fundamentally changed over the period of large increase in atmospheric CO2. However, the strong multi-decadal variability in ENSO is reflected in decades with quite different levels of ENSO effects on the ecosystem. Many multi-decadal subsets of the full record have statistically significant trends, using standard analysis techniques. These multi-decadal trends are not; however, representative of the record-length trend, nor are they a useful basis for projecting conditions in subsequent decades. Trend statistical significance is not a robust foundation for speculation about the future. We illustrate how the difficulties involved in determining whether a trend is statistically significant or not mean that, even after careful consideration, an unexpectedly large number of trends may reach standard statistical significance levels over the time spans for which many newer records are available, but still not

  18. Variability of fecal indicator bacteria in flowing and ponded waters in southern California: implications for bacterial TMDL development and implementation.

    PubMed

    He, Li-Ming; Lu, Jun; Shi, Weiyong

    2007-07-01

    Recreational water quality is assessed by using water quality objectives for fecal indicator bacteria (FIB) including total coliform, fecal coliform (or E. coli), and/or Enterococcus. It is required under the Clean Water Act that a TMDL be developed for a bacteria-impaired water body. The development and implementation of bacterial TMDLs has proven challenging and often difficult due to unknown source(s) of FIB. This study found that FIB levels varied significantly in flowing water, ponded water, and associated sediment. FIB levels in isolated ponded water in waterways were significantly higher than in flowing water. Sediment under ponded water contained a great amount of FIB. Furthermore, FIB concentrations in ponded water tended to increase with increasing water temperature and to decrease with increasing water salinity. The result provides the field evidence of survival/growth of FIB in water and sediment under ambient conditions in southern California. A holistic approach including natural sources (e.g., a reference system) should be considered for practical and applicable purposes while developing and implementing bacterial TMDLs for pathogen-impaired waterbodies. PMID:17543369

  19. Possible detachment zone in Precambrian rocks of Kanjamalai Hills, Cauvery Suture Zone, Southern India: Implications to accretionary tectonics

    NASA Astrophysics Data System (ADS)

    Mohanty, D. P.; Chetty, T. R. K.

    2014-07-01

    Existence of a possible detachment zone at Elampillai region, NW margin of Kanjamalai Hills, located in the northern part of Cauvery Suture Zone (CSZ), Southern India, is reported here for the first time. Detailed structural mapping provides anatomy of the zone, which are rarely preserved in Precambrian high grade terranes. The detachment surface separates two distinct rock units of contrasting lithological and structural characters: the upper and lower units. The detachment zone is characterized by a variety of fold styles with the predominance of tight isoclinal folds with varied plunge directions, limb rotations and the hinge line variations often leading to lift-off fold like geometries and deformed sheath folds. Presence of parasitic folding and associated penetrative strains seem to be controlled by differences in mechanical stratigraphy, relative thicknesses of the competent and incompetent units, and the structural relief of the underlying basement. Our present study in conjunction with other available geological, geochemical and geochronological data from the region indicates that the structures of the detachment zone are genetically related to thrust tectonics forming a part of subduction-accretion-collision tectonic history of the Neoproterozoic Gondwana suture.

  20. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications

    NASA Astrophysics Data System (ADS)

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-07-01

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time.

  1. Crustal structure of Precambrian terranes in the southern African subcontinent with implications for secular variation in crustal genesis

    NASA Astrophysics Data System (ADS)

    Kachingwe, Marsella; Nyblade, Andrew; Julià, Jordi

    2015-07-01

    New estimates of crustal thickness, Poisson's ratio and crustal shear wave velocity have been obtained for 39 stations in Angola, Botswana, the Democratic Republic of Congo, Malawi, Mozambique, Namibia, Rwanda, Tanzania and Zambia by modelling P-wave receiver functions using the H-κ stacking method and jointly inverting the receiver functions with Rayleigh-wave phase and group velocities. These estimates, combined with similar results from previous studies, have been examined for secular trends in Precambrian crustal structure within the southern African subcontinent. In both Archean and Proterozoic terranes we find similar Moho depths [38-39 ± 3 km SD (standard deviation)], crustal Poisson's ratio (0.26 ± 0.01 SD), mean crustal shear wave velocity (3.7 ± 0.1 km s-1 SD), and amounts of heterogeneity in the thickness of the mafic lower crust, as defined by shear wave velocities ≥4.0 km s-1. In addition, the amount of variability in these crustal parameters is similar within each individual age grouping as between age groupings. Thus, the results provide little evidence for secular variation in Precambrian crustal structure, including between Meso- and Neoarchean crust. This finding suggests that (1) continental crustal has been generated by similar processes since the Mesoarchean or (2) plate tectonic processes have reworked and modified the crust through time, erasing variations in structure resulting from crustal genesis.

  2. Pattern of Maternal Knowledge and Its Implications for Diarrhoea Control in Southern Malawi: Multilevel Thresholds of Change Analysis

    PubMed Central

    Masangwi, Salule Joseph; Grimason, Anthony Martin; Morse, Tracy Dawn; Kazembe, Lawrence; Ferguson, Neil; Jabu, George Christopher

    2012-01-01

    A survey was conducted in Southern Malawi to examine the pattern of mothers’ knowledge on diarrhoea. Diarrhoea morbidity in the district is estimated at 24.4%, statistically higher than the national average at 17%. Using hierarchically built data from a survey, a multilevel threshold of change analysis was used to determine predictors of knowledge about diarrhoeal aetiology, clinical features, and prevention. The results show a strong hierarchical structured pattern in overall maternal knowledge revealing differences between communities. Responsible mothers with primary or secondary school education were more likely to give more correct answers on diarrhoea knowledge than those without any formal education. Responsible mothers from communities without a health surveillance assistant were less likely to give more correct answers. The results show that differences in diarrhoeal knowledge do exist between communities and demonstrate that basic formal education is important in responsible mother’s understanding of diseases. The results also reveal the positive impact health surveillance assistants have in rural communities. PMID:22690176

  3. Presence of Zea luxurians (Durieu and Ascherson) Bird in Southern Brazil: Implications for the Conservation of Wild Relatives of Maize

    PubMed Central

    2015-01-01

    Records of the occurrence of wild relatives of maize in South American lowlands are unprecedented, especially in sympatric coexistence with landraces. This fact is relevant, because regions of occurrence of wild relatives of cultivated plants should be a priority for conservation, even if they do not correspond to the center of origin of the species. The aim of this study was to identify and characterize the wild relatives of maize in the Far West of Santa Catarina, southern Brazil. Therefore, phenotypic characterization was performed for five populations, based on 22 morphological traits deemed as fundamental for classifying the species of the genus Zea, and validated through the characterization of chromosomal knobs of two populations. The occurrence and distribution of teosinte populations were described through semi-structured interviews applied to a sample of 305 farmers. A total of 136 teosinte populations were identified; 75% of them occur spontaneously, 17% are cultivated populations, and 8% occur both ways, for the same farm. Populations that were characterized morphologically had trapezoidal fruits mostly, upright tassel branch (4–18), non-prominent main branch and glabrous glumes, with two protruding outer ribs and 8 inner ribs, on average. Cytogenetic analysis identified 10 pairs of homologous chromosomes (2n = 20) with 26 knobs, located in the terminal region of all chromosomes. The similarity of these results with the information reported in the literature indicates that the five populations of wild relatives of maize in this region of Santa Catarina belong to the botanical species Zea luxurians. PMID:26488577

  4. Deposits of the most recent eruption in the Southern Mono Craters, California: Description, interpretation and implications for regional marker tephras

    NASA Astrophysics Data System (ADS)

    Bursik, Marcus; Sieh, Kerry; Meltzner, Aron

    2014-04-01

    The penultimate eruption in the Mono Craters, Mono County, CA, USA, occurred in the southern section of the volcanic chain, and is herein named the South Mono eruption. The South Mono eruption occurred in 594-648cal A.D., and its products consist of widespread Plinian and phreatomagmatic fall, surge and pyroclastic flow deposits. The explosive deposits can be broken into Basal, Orange-Brown (surge dominated) and Upper subunits. The eruptive phase represented by the Upper beds was the most intense and voluminous, dispersing tephra over a wide region of eastern CA and western NV. South Coulee was the only effusive product of the eruption, and comprises the vast majority of the c. 0.4 cu km dense-rock equivalent (DRE) volume. The tephra overlies the deposits of Wilson Butte to the south, and is correlated herein with Wood's Tephra 2, and Walker Lake and Turupah Flats regional marker tephra layers. Other dates for these regional tephras may be the result of dating ash redeposited in debris flow events following fire.

  5. Paleoecological and Taphonomic Implications of Insect-Damaged Pleistocene Vertebrate Remains from Rancho La Brea, Southern California

    PubMed Central

    Holden, Anna R.; Harris, John M.; Timm, Robert M.

    2013-01-01

    The La Brea Tar Pits, the world’s richest and most important Late Pleistocene fossil locality, offers unsurpassed insights into southern California’s past environments. Recent studies at Rancho La Brea document that insects serve as sensitive and valuable paleoecological and taphonomic indicators. Of the thousands of fossil bird and mammal bones recovered from the Tar Pits, insect trace damage is thus far almost exclusively confined to the foot bones of large herbivores, especially bison, camel, and horse species. Our laboratory experiments with dermestid and tenebrionid beetles establish that the larvae of both consume bone, producing different characteristic feeding traces and providing the first documentation that tenebrionids consume bone. The presence of carcass-exploiting insects in the Rancho La Brea biota provides insight into the taphonomy of the asphaltic bone masses and the environmental conditions under which they accumulated. The succession of dermestids, tenebrionids, and indeterminate traces on many of the foot elements, combined with the climate restrictions and life cycles of these insects, indicate that carcasses could remain unsubmerged for at least 17–20 weeks, thus providing the most reliable estimate to date. Attribution of these traces also suggests that the asphaltic fossils only accumulated during warmer intervals of the Late Pleistocene. Forensic studies need to reevaluate the role of tenebrionids in carcass decomposition and other additional insects that modify bone. PMID:23843988

  6. Sedimentary and petrofacies analyses of the Amasiri Sandstone, southern Benue Trough, Nigeria: Implications for depositional environment and tectonic provenance

    NASA Astrophysics Data System (ADS)

    Okoro, A. U.; Igwe, E. O.; Nwajide, C. S.

    2016-11-01

    This study was undertaken to determine the depositional environment, provenance and tectonic setting for the Turonian Amasiri Sandstone, southern Benue Trough, Nigeria, using lithofacies analysis and re-appraisal of petrography of the sandstones. Local stratigraphy and field relationships show a thick succession of shales alternating with elongate/parallel sandstone ridges extending eastwards from Akpoha to Amasiri through Itigidi and Ugep to Apiapum areas. Lithofacies analysis reveals 9 lithofacies suggestive of storm (mass flow) and tidal shelf processes. These include dark grey to black laminated shale/silty mudstones, bioturbated mudstones, coquinoid limestones, very fine-grained bioturbated sandstones with shell hash/debris in places and limestone rip-up clasts, massive and chaotic sandy conglomerate with rip - up clasts, fine to medium-grained, parallel laminated sandstone, hummocky cross-stratified, massive, medium to coarse-grained sandstones, medium to very coarse-grained, planar cross-bedded sandstone, with clay-draped foresets and Ophiomorpha burrows, and coarse-grained trough cross-bedded sandstone. Petrofacies analysis identifies the sandstones as feldspathic and arkosic arenites. Ternary plot of framework mineralogy indicates derivation from an uplifted continental block related to the nearby Oban Massif and Cameroon Basement Complex.

  7. Interaction of ambient conditions and fecal coliform bacteria in southern Lake Michigan beach waters: Monitoring program implications

    USGS Publications Warehouse

    Whitman, Richard L.; Nevers, Meredith Becker; Gerovac, Paul J.

    1999-01-01

    Excessive fecal coliform bacteria in public swimming waters can potentially threaten visitor health. Fecal coliform bacteria (1984-1989) and Escherichia coli (1990-1995) density were monitored weekly at the Indiana Dunes National Lakeshore beaches for 12 summers, and park officials closed swimming areas when fecal coliform density exceeded the state water quality criteria (400 CFU fecal coliforms/ 100 ml; 235 CFU E. coli/100 ml water). Due to a 24-hour incubation in the fecal coliform and E. coli assays, beaches were closed the day after collection of high fecal coliform. Our analysis suggests that it is not possible to predict one day's fecal coliform count based on the previous day's results in waters taken from southern Lake Michigan beaches. Dispersal and deposition of bacteria were not uniform among sites or across time apparently due to interactions among environmental variables including rainfall, wind direction, water temperature, and bacteria source. Rainfall combined with northwest winds increased bacteria concentrations. Escherichia coli followed a seasonal trend with similar fluctuations in density among beaches. We suggest that the current beach monitoring protocol is inadequate for predicting fecal coliform density at the time of beach closure, and, subsequently, its use for ensuring visitor safety remains questionable.

  8. Inorganic contaminants from diffuse pollution in shallow groundwater of the Campanian Plain (Southern Italy). Implications for geochemical survey.

    PubMed

    Cuoco, E; Darrah, T H; Buono, G; Verrengia, G; De Francesco, S; Eymold, W K; Tedesco, D

    2015-02-01

    The Campanian Plain (CP) shallow aquifer (Southern Italy) represents a natural laboratory to validate geochemical methods for differentiating diffuse anthropogenic pollution from natural water-rock interaction processes. The CP is an appropriate study area because of numerous potential anthropogenic pollution vectors including agriculture, animal husbandry, septic/drainage sewage systems, and industry. In order to evaluate the potential for geochemical methods to differentiate various contamination vectors, 538 groundwater wells from the shallow aquifer in Campanian Plain (CP) were sampled. The dataset includes both major and trace elements. Natural water-rock interactions, which primarily depend on local lithology, control the majority of geochemical parameters, including most of the major and trace elements. Using prospective statistical methods in combination with the traditional geochemical techniques, we determined the chemical variables that are enriched by anthropogenic contamination (i.e. NO3, SO4 and U) by using NO3 as the diagnostic variable for detecting polluted groundwater. Synthetic agricultural fertilizers are responsible for the majority of SO4 and U pollution throughout the CP area. Both SO4 and U are present in the groundmass of synthetic fertilizers; the uranium concentration is specifically applicable as a tracer for non-point source agricultural fertilizer contamination. The recognition of non-geological (anthropogenic) inputs of these elements has to be considered in the geochemical investigations of contaminated aquifers.

  9. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications.

    PubMed

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-07-02

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time.

  10. The Extent and Nature of Fluidity in Typologies of Female Sex Work in Southern India: Implications for HIV Prevention Programs.

    PubMed

    Jain, Anrudh K; Saggurti, Niranjan

    2012-04-01

    These authors examine the nature and extent of fluidity in defining the typology of female sex work based on the place of solicitation or place of sex or both places together, and whether sex workers belonging to a particular typology are at increased risk of HIV in southern India. Data are drawn from a cross-sectional survey conducted during 2007-2008 among mobile female sex workers (N = 5301) in four Indian states. Findings from this study address an important policy issue: Should programmatic prevention interventions be spread to cover all places of sex work or be focused on a few places that cover a large majority of sex workers? Results indicate that most female sex workers, including those who are usually hard to reach such as those who are mobile or who use homes for soliciting clients or sex, can be reached programmatically multiple times by concentrating on a smaller number of categories, such as street-, lodge-, and brothel-based sex workers.

  11. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications

    PubMed Central

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-01-01

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time. PMID:26133245

  12. Review of SISA Student Dissertations on Library and Information Systems and Services in Eastern and Southern Africa.

    ERIC Educational Resources Information Center

    Chowdhury, G. G.; Tadesse, Taye T.

    1995-01-01

    Analyzes student dissertations at the School of Information Studies for Africa (SISA) at Addis Ababa University (Ethiopia) in order to present an overview of the library and information systems and services available in seven eastern and southern African countries: Ethiopia, Kenya, Malawi, Sudan, Tanzania, Uganda, and Zambia. (Author/LRW)

  13. Internet accessibility and usage among urban adolescents in Southern California: implications for web-based health research.

    PubMed

    Sun, Ping; Unger, Jennifer B; Palmer, Paula H; Gallaher, Peggy; Chou, Chih-Ping; Baezconde-Garbanati, Lourdes; Sussman, Steve; Johnson, C Anderson

    2005-10-01

    The World Wide Web (WWW) poses a distinct capability to offer interventions tailored to the individual's characteristics. To fine tune the tailoring process, studies are needed to explore how Internet accessibility and usage are related to demographic, psychosocial, behavioral, and other health related characteristics. This study was based on a cross-sectional survey conducted on 2373 7th grade students of various ethnic groups in Southern California. Measures of Internet use included Internet use at school or at home, Email use, chat-room use, and Internet favoring. Logistic regressions were conducted to assess the associations between Internet uses with selected demographic, psychosocial, behavioral variables and self-reported health statuses. The proportion of students who could access the Internet at school or home was 90% and 40%, separately. Nearly all (99%) of the respondents could access the Internet either at school or at home. Higher SES and Asian ethnicity were associated with higher internet use. Among those who could access the Internet and after adjusting for the selected demographic and psychosocial variables, depression was positively related with chat-room use and using the Internet longer than 1 hour per day at home, and hostility was positively related with Internet favoring (All ORs = 1.2 for +1 STD, p < 0.05). Less parental monitoring and more unsupervised time were positively related to email use, chat-room use, and at home Internet use (ORs for +1 STD ranged from 1.2 to 2.0, all p < 0.05), but not related to at school Internet use. Substance use was positively related to email use, chat-room use, and at home Internet use (OR for "used" vs. "not used" ranged from 1.2 to 4.0, p < 0.05). Self-reported health problems were associated with higher levels of Internet use at home but lower levels of Internet use at school. More physical activity was related to more email use (OR = 1.3 for +1 STD), chat room use (OR = 1.2 for +1 STD), and at school

  14. Fault Zone Architecture and Mineralogy: Implications in Fluid Flow and Permeability in Crustal Scale Fault Zones in the Southern Andes.

    NASA Astrophysics Data System (ADS)

    Roquer, T.; Terrón, E.; Perez-Flores, P.; Arancibia, G.; Cembrano, J. M.

    2014-12-01

    Fluid flow in the upper crust is controlled by the permeability and interconnection of fractures in the fault zones. The permeability within the fault zone is determined by its activity, architecture and, in particular, by the mineralogy of the core and the damage zone. Whereas the permeability structure of a fault zone can be defined by the volume proportion of the core with respect to the damage zone, the relationship between the mineralogy and permeability along fault zones still remains obscure. This work examines structural and mineralogical data to show the relationship between the mineral composition of the fault zone with its permeability in the Liquiñe-Ofqui Fault System (LOFS) and the Arc-oblique Long-lived Fault Systems (ALFS), Southern Chile. The LOFS is an active ca. 1200 km long strike-slip Cenozoic intra-arc structure that strikes NNE in its master traces and NE in its subsidiary traces, with dextral and dextral-normal movement mostly developed in the last 6 My. Although the LOFS and the ALFS cross-cut each other, the ALFS is an apparently older basement fault system where seismic and field evidences record sinistral, sinistral-normal and sinistral-reverse movements. One 22-m-long NE transect was mapped orthogonal to a segment of the ALFS, where host rocks are Miocene andesitic rocks. Structural and XRD sampling were conducted in the core and damage zone. Structural mapping shows a multiple core, NW-striking fault zone with foliated gouge and an asymmetric damage zone, where the hanging wall has significantly higher mesoscopic fracture density than the footwall. The hanging wall is characterized by NW-striking, steeply dipping veins. Preliminary XRD results indicate the presence of homogenously distributed Ca-rich zeolite (mainly laumontite) in the core and the veins of the damage zone, which could indicate that the core acted as a conduit for low-temperature (ca. 220°C) fluids.

  15. Morphological properties of tunnel valleys of the southern sector of the Laurentide Ice Sheet and implications for their formation

    NASA Astrophysics Data System (ADS)

    Livingstone, Stephen J.; Clark, Chris D.

    2016-07-01

    Tunnel valleys have been widely reported on the bed of former ice sheets and are considered an important expression of subglacial meltwater drainage. Although known to have been cut by erosive meltwater flow, the water source and development of channels has been widely debated; ranging between outburst flood events through to gradually occurring channel propagation. We have mapped and analysed the spatial pattern and morphometry of tunnel valleys and associated glacial landforms along the southern sector of the former Laurentide Ice Sheet from high-resolution digital elevation models. Around 2000 tunnel valleys have been mapped, revealing an organised pattern of sub-parallel, semi-regularly spaced valleys that form in distinctive clusters. The tunnel valleys are typically < 20 km long, and 0.5-3 km wide, although their width varies considerably down-valley. They preferentially terminate at moraines, which suggests that formation is time dependent; while we also observe some tunnel valleys that have grown headwards out of hill-hole pairs. Analysis of cross-cutting relationships between tunnel valleys, moraines and outwash fans permits reconstruction of channel development in relation to the retreating ice margin. This palaeo-drainage reconstruction demonstrates incremental growth of most valleys, with some used repeatedly or for long periods, during deglaciation, while others were abandoned shortly after their formation. Our data and interpretation support gradual (rather than a single-event) formation of most tunnel valleys with secondary contributions from flood drainage of subglacial and or supraglacially stored water down individual tunnel valleys. The distribution and morphology of tunnel valleys is shown to be sensitive to regional factors such as basal thermal regime, ice and bed topography, timing and climate.

  16. Peraluminous sapphirine-cordierite pods in Mg-rich orthopyroxene granulite from southern India: Implications for lower crustal processes

    NASA Astrophysics Data System (ADS)

    Shazia, J. R.; Santosh, M.; Sajeev, K.

    2012-09-01

    Sapphirine-cordierite intergrowths occur as pods within garnet-absent, high-Mg orthopyroxene-granulite xenoliths in the Kambam valley, Madurai Block, southern India. Whereas the cores of the pods are composed of sapphirine (XMg = 0.871-0.897) - cordierite (XMg = 0.892-0.931) intergrowth along with rutile, zircon and monazite, the rims are characterized by cordierite, apatite, plagioclase, K-feldspar, quartz and minor calcite. The surrounding matrix comprises orthopyroxene (maximum Al2O3 4.1 wt.%, XMg 0.848-0.850), plagioclase, biotite and quartz, similar to the assemblage in the surrounding charnockites. Sapphirine in the Kambam rocks is characterized by high Al contents with an end-member composition in the range of 7:9:3 and 3:5:1. The occurrence of peraluminous sapphirine in association with cordierite and in the absence of phases such as sillimanite and garnet is distinct from ultrahigh-temperature assemblages in other localities within the Madurai Block. The peraluminous composition of the pods suggests that these domains could represent cryptic pathways through which aluminous melts migrated. The reaction of such peraluminous melts with Mg-rich orthopyroxene in the host granulite at temperatures of 1025 °C and pressures around 8 kbar as computed from phase equilibria modeling followed by an isobaric cooling is inferred to have generated the sapphirine-cordierite pods. The unusual high-Mg orthopyroxene granulite suggests interaction of supracrustal rocks with mafic magmas, which probably acted as the heat source for the partial melting of lower crust and UHT metamorphism.

  17. Anomalous crustal and lithospheric mantle structure of southern part of the Vindhyan Basin and its geodynamic implications

    NASA Astrophysics Data System (ADS)

    Pandey, O. P.; Srivastava, R. P.; Vedanti, N.; Dutta, S.; Dimri, V. P.

    2014-09-01

    Tectonically active Vindhyan intracratonic basin situated in central India, forms one of the largest Proterozoic sedimentary basins of the world. Possibility of hydrocarbon occurrences in thick sediments of the southern part of this basin, has led to surge in geological and geophysical investigations by various agencies. An attempt to synthesize such multiparametric data in an integrated manner, has provided a new understanding to the prevailing crustal configuration, thermal regime and nature of its geodynamic evolution. Apparently, this region has been subjected to sustained uplift, erosion and magmatism followed by crustal extension, rifting and subsidence due to episodic thermal interaction of the crust with the hot underlying mantle. Almost 5-6 km thick sedimentation took place in the deep faulted Jabera Basin, either directly over the Bijawar/Mahakoshal group of mafic rocks or high velocity-high density exhumed middle part of the crust. Detailed gravity observations indicate further extension of the basin probably beyond NSL rift in the south. A high heat flow of about 78 mW/m2 has also been estimated for this basin, which is characterized by extremely high Moho temperatures (exceeding 1000 °C) and mantle heat flow (56 mW/m2) besides a very thin lithospheric lid of only about 50 km. Many areas of this terrain are thickly underplated by infused magmas and from some segments, granitic-gneissic upper crust has either been completely eroded or now only a thin veneer of such rocks exists due to sustained exhumation of deep seated rocks. A 5-8 km thick retrogressed metasomatized zone, with significantly reduced velocities, has also been identified around mid to lower crustal transition.

  18. Hillslope response to knickpoint migration in the Southern Appalachians: Implications for the evolution of post-orogenic landscapes

    USGS Publications Warehouse

    Wegmann, S.F.G.; Franke, K.L.; Hughes, S.; Lewis, R.Q.; Lyons, N.; Paris, P.; Ross, K.; Bauer, J.B.; Witt, A.C.

    2011-01-01

    The southern Appalachians represent a landscape characterized by locally high topographic relief, steep slopes, and frequent mass movement in the absence of significant tectonic forcing for at least the last 200 Ma. The fundamental processes responsible for landscape evolution in a post-orogenic landscape remain enigmatic. The non-glaciated Cullasaja River basin of south-western North Carolina, with uniform lithology, frequent debris flows, and the availability of high-resolution airborne lidar DEMs, is an ideal natural setting to study landscape evolution in a post-orogenic landscape through the lens of hillslope-channel coupling. This investigation is limited to channels with upslope contributing areas >2.7 km2, a conservative estimate of the transition from fluvial to debris-flow dominated channel processes. Values of normalized hypsometry, hypsometric integral, and mean slope vs elevation are used for 14 tributary basins and the Cullasaja basin as a whole to characterize landscape evolution following upstream knickpoint migration. Results highlight the existence of a transient spatial relationship between knickpoints present along the fluvial network of the Cullasaja basin and adjacent hillslopes. Metrics of topography (relief, slope gradient) and hillslope activity (landslide frequency) exhibit significant downstream increases below the current position of major knickpoints. The transient effect of knickpoint-driven channel incision on basin hillslopes is captured by measuring the relief, mean slope steepness, and mass movement frequency of tributary basins and comparing these results with the distance from major knickpoints along the Cullasaja River. A conceptual model of area-elevation and slope distributions is presented that may be representative of post-orogenic landscape evolution in analogous geologic settings. Importantly, the model explains how knickpoint migration and channel- hillslope coupling is an important factor in tectonically-inactive (i

  19. Quaternary morphotectonic mapping of the Wadi Araba and implications for the tectonic activity of the southern Dead Sea fault

    NASA Astrophysics Data System (ADS)

    Le BéOn, Maryline; Klinger, Yann; MéRiaux, Anne-Sophie; Al-Qaryouti, Mahmoud; Finkel, Robert C.; Mayyas, Omar; Tapponnier, Paul

    2012-10-01

    The Dead Sea strike-slip fault accommodates the northward motion of Arabia relative to Sinai at a rate of ˜5 mm/yr. The southern segment of the fault, the Wadi Araba fault, runs along a valley blanketed in Quaternary sediments. We first focused on understanding the relative and absolute timing of emplacement of the alluvial surfaces. We then determined the probable source of the sediments before assessing their lateral offset to constrain the late Pleistocene fault slip rate. Seven successive morphostratigraphic levels were identified. At two sites, we recognized an alluvial sequence of five to seven successive levels with ages getting younger northward, a pattern consistent with the western block moving southward relative to two fixed feeding channels located to the east. Surface samples were collected for10Be cosmogenic radionuclide dating. Fans F3 and F5 were found to be synchronous from site to site, at 102 ± 26 ka and 324 ± 22 ka, respectively, while F4 could be dated at 163 ± 19 ka at one site only. These are minimum ages, assuming no erosion of the alluvial surfaces. At least two of these periods are correlated with wet periods that are regionally well documented. Further analyses of tectonic offsets are affected in most cases by large uncertainties due to the configuration of the sites. They indicate maximum offsets of ˜5.5 km for the oldest, possibly ˜1 Ma old, surfaces. They lead to bracketing of the fault slip rate between 5 and 12 mm/yr, with preferred values of 5-7 mm/yr, for the last 300 ka.

  20. Predicted implications of using percentage weight gain as single discharge criterion in management of acute malnutrition in rural southern Ethiopia.

    PubMed

    Forsén, Emmanuel; Tadesse, Elazar; Berhane, Yemane; Ekström, Eva-Charlotte

    2015-10-01

    Mid-upper arm circumference (MUAC) is increasingly used in identifying and admitting children with acute malnutrition for treatment. It is easy to use because it does not involve height assessment, but its use calls for alternative discharge criteria. This study examined how use of percentage weight gain as discharge criterion would affect the nutritional status of children admitted into a community-based management programme for acute malnutrition in rural southern Ethiopia. Non-oedematous children (n = 631) aged 6-59 months and having a MUAC of <125 mm were studied. By simulation, 10%, 15% and 20% weight was added to admission weight and their nutritional status by weight-for-height z-score (WHZ) was determined at each target. Moderate and severe wasting according to World Health Organization WHZ definitions was used as outcome. Applying the most commonly recommended target of 15% weight gain resulted in 9% of children with admission MUAC <115 mm still being moderately or severely wasted at theoretical discharge. In children with admission MUAC 115-124 mm, 10% of weight gain was sufficient to generate a similar result. Children failing to recover were the ones with the poorest nutritional status at admission. Increasing the percentage weight gain targets in the two groups to 20% and 15%, respectively, would largely resolve wasting but likely lead to increased programme costs by keeping already recovered children in the programme. Further research is needed on appropriate discharge procedures in programmes using MUAC for screening and admission.

  1. Implications of topographic relief on the brittle-to-plastic boundary beneath the southern Central Range, Taiwan

    NASA Astrophysics Data System (ADS)

    Cavallotti, C. J.; Lewis, J. C.

    2015-12-01

    The result of the ongoing arc-continent collision between the Eurasian (EU) and Philippine Sea (PSP) plates, Taiwan is an important tool in understanding the real time mechanics of the mountain building process. We show an apparent gap in seismicity beneath Taiwan's Southern Central Range that may represent the presence of a volume of rock lacking the shear strength required to record brittle processes. A spatially accurate 3D map was created, utilizing data recorded for over 8000 seismic events beneath Taiwan and the surrounding area, and shows an elongate aseismic volume trending northeast southwest generally parallel to the topographic grain of the island. Published P-wave data shows an area nearly coincident with the aseismic zone with lower velocities at depths of 7.5km in the west to nearly 40km in the east which suggests a difference in density (and rheology) from the surrounding, seismically active, areas. Strain inversions assuming a micropolar model for crustal deformation suggest systematic changes in strain tensor geometry from east to west across the hypothesized density boundary. Preliminary results indicate that seismogenic strain along the western margin of the aseismic zone accommodates crustal thinning with stretching oblique to the orogen. In contrast, on the east side of the aseismic zone we see crustal thickening with minimum stretching (shortening) subparallel to PSP-EU motion. The profound change in strain geometry suggests that the asiesmic zone is a partially ductile volume of rock caused by interactions of the EU and PSP beneath Taiwan. We hypothesize that if the rheology contrast is sufficient, higher spatial resolution inversions may reveal that events near the seismic/aseismic interface exhibit Andersonian-like behavior wherein one principal strain axis would lie orthogonal at any given point to a surface mapped to this boundary. Alternatively, if the contrast is smaller the inverted strain geometries may vary systematically and provide

  2. Occurrence of organophosphorus flame retardants in indoor dust in multiple microenvironments of southern China and implications for human exposure.

    PubMed

    He, Chun-Tao; Zheng, Jing; Qiao, Lin; Chen, She-Jun; Yang, Jun-Zhi; Yuan, Jian-Gang; Yang, Zhong-Yi; Mai, Bi-Xian

    2015-08-01

    Organophosphorus flame retardants (OPFRs) are important alternatives to brominated flame retardants (BFRs), but information on their contamination of the environment in China is rare. We examined the occurrence of 12 OPFRs in indoor dust in four microenvironments of southern China, including a rural electronic waste (e-waste) recycling area, a rural non-e-waste area, urban homes, and urban college dormitory rooms. The OPFR concentrations (with a median of 25.0 μg g(-1)) were highest in the e-waste area, and the concentrations in other three areas were lower and comparable (7.48-11.0 μg g(-1)). The levels of OPFRs in the present study were generally relatively lower than the levels of OPFRs found in Europe, Canada, and Japan because BFRs are still widely used as the major FRs in China. The composition profile of OPFRs in the e-waste area was dominated by tricresyl phosphate (TCP) (accounting for 40.7%, on average), while tris(2-chloroethyl) phosphate (TCEP) was the most abundant OPFR (64.4%) in the urban areas (homes and college dormitories). These two distribution patterns represent two OPFR sources (i.e., emissions from past e-waste and from current household products and building materials). The difference in the OPFR profiles in the rural area relative to the OPFR profiles in the urban and e-waste areas suggests that the occurrence of OPFRs is due mainly to emissions from characteristic household products in rural homes. Although human exposures to all the OPFRs were under the reference doses, the health risk for residents in the e-waste area is a concern, considering the poor sanitary conditions in this area and exposure from other sources.

  3. Occurrence of organophosphorus flame retardants in indoor dust in multiple microenvironments of southern China and implications for human exposure.

    PubMed

    He, Chun-Tao; Zheng, Jing; Qiao, Lin; Chen, She-Jun; Yang, Jun-Zhi; Yuan, Jian-Gang; Yang, Zhong-Yi; Mai, Bi-Xian

    2015-08-01

    Organophosphorus flame retardants (OPFRs) are important alternatives to brominated flame retardants (BFRs), but information on their contamination of the environment in China is rare. We examined the occurrence of 12 OPFRs in indoor dust in four microenvironments of southern China, including a rural electronic waste (e-waste) recycling area, a rural non-e-waste area, urban homes, and urban college dormitory rooms. The OPFR concentrations (with a median of 25.0 μg g(-1)) were highest in the e-waste area, and the concentrations in other three areas were lower and comparable (7.48-11.0 μg g(-1)). The levels of OPFRs in the present study were generally relatively lower than the levels of OPFRs found in Europe, Canada, and Japan because BFRs are still widely used as the major FRs in China. The composition profile of OPFRs in the e-waste area was dominated by tricresyl phosphate (TCP) (accounting for 40.7%, on average), while tris(2-chloroethyl) phosphate (TCEP) was the most abundant OPFR (64.4%) in the urban areas (homes and college dormitories). These two distribution patterns represent two OPFR sources (i.e., emissions from past e-waste and from current household products and building materials). The difference in the OPFR profiles in the rural area relative to the OPFR profiles in the urban and e-waste areas suggests that the occurrence of OPFRs is due mainly to emissions from characteristic household products in rural homes. Although human exposures to all the OPFRs were under the reference doses, the health risk for residents in the e-waste area is a concern, considering the poor sanitary conditions in this area and exposure from other sources. PMID:25898308

  4. Analysis of coastal sea-level station records and implications for tsunami monitoring in the Adriatic Apulia region, southern Italy

    NASA Astrophysics Data System (ADS)

    Bressan, Lidia; Tinti, Stefano; Tallarico, Andrea

    2015-04-01

    The region of Apulia, southern Italy, was theater of one of the largest tsunami disaster in Italian history (the 30 July 1627 event) and is considered to be exposed to tsunami hazard coming from local Italian sources as well as from sources on the eastern side of the Adriatic and from the Ionian sea, including the Hellenic Arc earthquakes. Scientific interest for tsunami studies and monitoring in the region is only recent and this theme was specifically addressed by the international project OTRIONS, coordinated by the University of Bari. In the frame of this project the University of Bologna contributed to the analysis of the tsunami hazard and to the evaluation of the regional tide-gauge network with the scope of assessing its adequacy for tsunami monitoring. This latter is the main topic of the present work. In eastern Apulia, facing the Adriatic sea, the sea-level data network is sufficiently dense being formed of stations of the Italian tide-gauge network (Rete Mareografica Nazionale, RMN), of four additional stations operated by the Apulia Port Authority (in Brindisi, Ischitella, Manfredonia and Porto Cesareo) and of two more stations that were installed in the harbours of Barletta and Monopoli in the frame of the project OTRIONS with real-time data transmission and 1-sec sampling period. Pre-processing of the sea-level data of these stations included quality check and spectral analysis. Where the sampling rate was adequate, the records were also examined by means of the specific tools provided by the TEDA package. This is a Tsunami Early Detection Algorithm, developed by the Tsunami Research Team of the University of Bologna, that allows one to characterize the sea-level background signal in the typical tsunami frequency window (from 1 to several minutes) and consequently to optimize TEDA parameters for an efficient tsunami detection. The results of the analysis show stability of the spectral content and seasonal variations.

  5. Paleoclimatic implications of fossil shoreline deposits in the southern basin and range province during the Pleistocene-Holocene transition

    NASA Astrophysics Data System (ADS)

    Kowler, A. L.

    2010-12-01

    Paleolake shoreline deposits throughout the southern Basin and Range (SBAR) signify past intervals of steady-state climatic conditions occuring during the late Pleistocene slightly before, as well as after the Last Glacial Maximum (LGM; ~23-19 Ka). Unfortunately, a lack of knowledge about the age of fossil shoreline deposits—due to C-14 related uncertainties and incomplete dating of shorelines—has resulted in a large gap in our knowledge about past climatic and surface hydrologic conditions in the SBAR. Several studies collectively reveal multiple lake level oscillations during the LGM and last part of the Pleistocene, with reasonably well dated shoreline deposits existing for only four paleolakes: one in central New Mexico (Estancia), two in southwestern New Mexico (Playas and Cloverdale), and one in southeastern Arizona (Cochise). In summary, there is evidence for a pre-LGM high-stand at Cochise (>26 Ka), LGM high-stands at Estancia and Cloverdale (>20-16 Ka), deglacial age high-stands at Playas and Cochise (16-13 Ka), and latest Pleistocene-early Holocene still stands of as yet undetermined elevation at Playas and Estancia (13-9K). Further, the absence of high-stands from 11-10 Ka suggests that the Younger Dryas climatic reversal—which is detected in the stable O isotopic composition of speleothems from Cave-of-the-Bells in southeastern Arizona—was marked there by a decrease in mean annual air temperature without a significant increase in precipitation. Alternatively, if a return to glacial precipitation levels did occur, then it was for an interval so short that sedimentological evidence was not preserved. This presentation will cover the afore mentioned chronologies, along with discussion about associated atmospheric circulation patterns in the SBAR and across western North America.

  6. Diagenetic Patterns of the Cretaceous Baseline Sandstone, Southern Nevada: Implications for Controls on Iron-Oxide Cementation and Coloration

    NASA Astrophysics Data System (ADS)

    Duncan, C. J.; Chan, M. A.

    2015-12-01

    The Cretaceous Baseline Sandstone of the Sevier foreland basin deposits in southern Nevada exhibits intense diagenetic iron-oxide coloration and bleaching, and contains abundant cemented masses. The Baseline Formation is ~1 km thick with three alluvial to fluvial members: the basal White (Kbw) Member, overlain by coeval Red (Kbr) and Overton Conglomerate (Kbo) Members. Iron-oxide diagenetic features occur in two broad classes: 1) bedding parallel coloration facies of diffuse to banded red, pink, purple, white, to yellow colors; and 2) concretionary facies of heavily cemented horizons, pods/lenses, spherical to spheroidal concretions, boxworks, pipes, and irregular concretion forms. A distinctive geometry is the occurrence of large (~1 m diameter) spherical "beach ball" concretions within the Kbr. Preliminary mapping of diagenetic features shows that concretionary facies are more common within a ~125 m interval near the bottom of Kbw, and within the lower ~125 m of Kbr. Intense coloration changes are present throughout Kbw but occur only in the lowermost ~150 m of Kbr. In the Kbw, concretionary forms commonly occur in stratigraphic intervals of fine-grained sandstone, siltstone, and mudstone lithologies, whereas cemented masses are much less common in stratigraphic intervals composed of medium-grained sandstone and conglomerate lithologies. Additionally, both Kbw and Kbr Members exhibit rare examples of wood fragments in the center of iron-oxide concretions, suggesting the importance of organics as nucleation sites for precipitation. The distribution of complex and overprinted diagenetic patterns indicates nested scales of processes involving iron-oxide dissolution, mobilization, and precipitation. Overall stratigraphic architecture influenced formation-scale patterns, but specific lithologies and textures influenced the type and distribution of diagenetic facies at outcrop scales, and organic content encouraged cementation at grain-scales.

  7. Controls on large landslide distribution and implications for the geomorphic evolution of the southern interior Columbia River basin

    USGS Publications Warehouse

    Safran, E.B.; Anderson, S.W.; Mills-Novoa, M.; House, P.K.; Ely, L.

    2011-01-01

    Large landslides (>0.1 km2) are important agents of geomorphic change. While most common in rugged mountain ranges, large landslides can also be widespread in relatively low-relief (several 100 m) terrain, where their distribution has been relatively little studied. A fuller understanding of the role of large landslides in landscape evolution requires addressing this gap, since the distribution of large landslides may affect broad regions through interactions with channel processes, and since the dominant controls on landslide distribution might be expected to vary with tectonic setting. We documented >400 landslides between 0.1 and ~40 km2 across ~140,000 km2 of eastern Oregon, in the semiarid, southern interior Columbia River basin. The mapped landslides cluster in a NW-SE-trending band that is 50-100 km wide. Landslides predominantly occur where even modest local relief (~100 m) exists near key contacts between weak sedimentary or volcaniclastic rock and coherent cap rock. Fault density exerts no control on landslide distribution, while ~10% of mapped landslides cluster within 3-10 km of mapped fold axes. Landslide occurrence is curtailed to the NE by thick packages of coherent basalt and to the SW by limited local relief. Our results suggest that future mass movements will localize in areas stratigraphically preconditioned for landsliding by a geologic history of fluviolacustrine and volcaniclastic sedimentation and episodic capping by coherent lava flows. In such areas, episodic landsliding may persist for hundreds of thousands of years or more, producing valley wall slopes of ~7??-13?? and impacting local channels with an evolving array of mass movement styles. ?? 2011 Geological Society of America.

  8. Variability in New Shortening Estimates from Southern Peru (12-14S); Implications for Mass Balance of the Andean Plateau.

    NASA Astrophysics Data System (ADS)

    Gotberg, N.; McQuarrie, N.

    2008-12-01

    One of the fundamental questions of interest with regards to the Andean Plateau is the mass balance of material needed to create and sustain a 3-4 km high plateau. Is crustal shortening sufficient to support an isostatically compensated crust of 60-70km? We present new estimates of shortening across the northern margin of the Andean Plateau. The cross section extent, from the eastern edge of the volcanic arc to foreland basin, is approximately one half of the physiographic width of the Andean Plateau in Peru. Cross sectional shortening estimates in southern Peru (12-14°S) provide a best estimate of 123 km or 40% shortening with an absolute minimum estimate of 86 km or 30% and absolute maximum estimate of 275 km or 60%. We determined the maximum and minimum shortening estimates using the cross sectional area and possible variations in assumptions made about the amount of erosion, detachment dip, involvement of basement thrusts and displacement along faults. The best estimate of shortening is well short of the required 240-300km of shortening needed in order to account for a 60-70km thick crust under the entire plateau. This suggests that for an isostatically equilibrated crust either 1) there is a significant amount of shortening (~150km) in the western half of the plateau which, is hidden by the volcanic arc or 2) crustal material is being added to the Peruvian section of the Andean Plateau either through lower crustal flow or a process of magmatic underplating followed by differentiation and delamination.

  9. Climatic Implications of the Observed Temperature Dependence of the Liquid Water Path of Low Clouds in the Southern Great Plains

    NASA Technical Reports Server (NTRS)

    DelGenio, Anthony

    1999-01-01

    Satellite observations of low-level clouds have challenged the assumption that adiabatic liquid water content combined with constant physical thickness will lead to a negative cloud optics feedback in a decadal climate change. We explore the reasons for the satellite results using four years of surface remote sensing data from the Atmospheric Radiation Measurement Program Cloud and Radiation Testbed site in the Southern Great Plains of the United States. We find that low cloud liquid water path is approximately invariant with temperature in winter but decreases strongly with temperature in summer, consistent with the satellite inferences at this latitude. This behavior occurs because liquid water content shows no detectable temperature dependence while cloud physical thickness decreases with warming. Thinning of clouds with warming is observed on seasonal, synoptic, and diurnal time scales; it is most obvious in the warm sectors of baroclinic waves. Although cloud top is observed to slightly descend with warming, the primary cause of thinning, is the ascent of cloud base due to the reduction in surface relative humidity and the concomitant increase in the lifting condensation level of surface air. Low cloud liquid water path is not observed to be a continuous function of temperature. Rather, the behavior we observe is best explained as a transition in the frequency of occurrence of different boundary layer types. At cold temperatures, a mixture of stratified and convective boundary layers is observed, leading to a broad distribution of liquid water path values, while at warm temperatures, only convective boundary layers with small liquid water paths, some of them decoupled, are observed. Our results, combined with the earlier satellite inferences, imply that the commonly quoted 1.5C lower limit for the equilibrium global climate sensitivity to a doubling of CO2 which is based on models with near-adiabatic liquid water behavior and constant physical thickness

  10. Climatic Implications of the Observed Temperature Dependence of the Liquid Water Path of Low Clouds in the Southern Great Plains

    NASA Technical Reports Server (NTRS)

    DelGenio, Anthony D.; Wolf, Audrey B.

    1999-01-01

    Satellite observations of low-level clouds have challenged the assumption that adiabatic liquid water content combined with constant physical thickness will lead to a negative cloud optics feedback in a decadal climate change. We explore the reasons for the satellite results using four years of surface remote sensing data from the Atmospheric Radiation Measurement Program Cloud and Radiation Testbed site in the Southern Great Plains of the United States. We find that low cloud liquid water path is approximately invariant with temperature in winter but decreases strongly with temperature in summer, consistent with the satellite inferences at this latitude. This behavior occurs because liquid water content shows no detectable temperature dependence while cloud physical thickness decreases with warming. Thinning of clouds with warming is observed on seasonal, synoptic, and diurnal time scales; it is most obvious in the warm sectors of baroclinic waves. Although cloud top is observed to slightly descend with warming, the primary cause of thinning is the ascent of cloud base due to the reduction in surface relative humidity and the concomitant increase in the lifting condensation level of surface air. Low cloud liquid water path is not observed to be a continuous function of temperature. Rather, the behavior we observe is best explained as a transition in the frequency of occurrence of different boundary layer types: At cold temperatures, a mixture of stratified and convective boundary layers is observed, leading to a broad distribution of liquid water path values, while at warm temperatures, only convective boundary layers with small liquid water paths, some of them decoupled, are observed. Our results, combined with the earlier satellite inferences, imply that the commonly quoted 1.50 C lower limit for the equilibrium global climate sensitivity to a doubling of CO2, which is based on models with near-adiabatic liquid water behavior and constant physical thickness

  11. High-pressure metamorphism in the southern New England Orogen: Implications for long-lived accretionary orogenesis in eastern Australia

    NASA Astrophysics Data System (ADS)

    Phillips, G.; Offler, R.; Rubatto, D.; Phillips, D.

    2015-09-01

    New geochemical, metamorphic, and isotopic data are presented from high-pressure metamorphic rocks in the southern New England Orogen (eastern Australia). Conventional and optimal thermobarometry are augmented by U-Pb zircon and 40Ar/39Ar phengite dating to define pressure-temperature-time (P-T-t) histories for the rocks. The P-T-t histories are compared with competing geodynamic models for the Tasmanides, which can be summarized as (i) a retreating orogen model, the Tasmanides formed above a continuous, west dipping, and eastward retreating subduction zone, and (ii) a punctuated orogen model, the Tasmanides formed by several arc accretion, subduction flip, and/or transference events. Whereas both scenarios are potentially supported by the new data, an overlap between the timing of metamorphic recrystallization and key stages of Tasmanides evolution favors a relationship between a single, long-lived subduction zone and the formation, exhumation, and exposure of the high-pressure rocks. By comparison with the retreating orogen model, the following links with the P-T-t histories emerge: (i) exhumation and underplating of oceanic eclogite during the Delamerian Orogeny, (ii) recrystallization of underplated and exhuming high-pressure rocks at amphibolite facies conditions coeval with a period of rollback, and (iii) selective recrystallization of high-pressure rocks at blueschist facies conditions, reflecting metamorphism in a cooled subduction zone. The retreating orogen model can also account for the anomalous location of the Cambrian-Ordovician high-pressure rocks in the Devonian-Carboniferous New England Orogen, where sequential rollback cycles detached and translated parts of the leading edge of the overriding plate to the next, younger orogenic cycle.

  12. Dengue hemorrhagic fever outbreak in children in Port Sudan.

    PubMed

    Malik, Amal; Earhart, Kenneth; Mohareb, Emad; Saad, Magdi; Saeed, Mubarak; Ageep, Ali; Soliman, Atef

    2011-03-01

    Dengue fever (DF)/dengue hemorrhagic fever (DHF) has emerged as a global public health problem with countries in Asia and the Pacific sharing more than 70% of the disease burden. In 2004-2005 a total of 312 cases admitted to Pediatric and Sea Port Hospitals in Port Sudan were clinically diagnosed as DHF. The mortality rate recorded was 3.8% (n=12). Of the cases 73.4% were patients 5-15 years of age. A total of 91.2% of cases were admitted during May and June 2005 with 49.4% residing in the eastern region of Port Sudan. Dengue shock syndrome was observed in 37 of 312 (11.9%). All patients had thrombocytopenia with platelets count ranged from <100,000 to <150,000 cell/mm³. Of the 40 sera tested using RAPID-cassette test in the Khartoum Central Public Health Lab, 36 (90%) were dengue IgM positive. A subset of these sera (n=23) were sent to NAMRU-3 and confirmed by IgM-capture ELISA; 9 of 23 were PCR positive for dengue serotype 3.

  13. An examination of the 1990-91 famine in Sudan.

    PubMed

    Patel, M

    1994-12-01

    Shortly before and during the harvest of 1990, a series of warnings were issued by concerned international and UN agencies that Sudan would experience a very poor harvest followed by an acute food shortage over the period 1990-91. The 1990 harvest was estimated to be similar to that obtained in 1984. After the very poor harvest in 1984, Sudan experienced a major famine during which deaths may have numbered in the hundreds of thousands. There were fears that this experience might be repeated in 1990-91. By the time of the subsequent 1991 harvest, it was clear to all that a severe food crisis had been experienced. There were severe shortages of water and food and very high malnutrition rates of children were noted by UNICEF across a wide range of areas. Despite these adverse indications, starvation deaths were probably numbered in thousands, rather than hundreds of thousands. Famine mortality, which may include deaths from famine associated disease, was similarly low. The initial predictions, it now seems, may have over-estimated famine mortality almost one hundred times. Several potential explanations of the over-estimate are examined. These include prediction errors, government and donor responses to the drought such as food aid and immunization, and traditional community and household level coping strategies in times of food shortage.

  14. Electrochemical Determination of Trace Sudan I Contamination in Chili Powder at Carbon Nanotube Modified Electrodes

    PubMed Central

    Ming, Liang; Xi, Xia; Chen, Tingting; Liu, Jie

    2008-01-01

    We have developed a simple, convenient and inexpensive voltammetric method for determining trace Sudan I contamination in chili powder, based on the catalyzed electrochemical reduction of Sudan I at the carbon nanotube modified electrode. Under optimized conditions, the method exhibited acceptable analytical performance in terms of linearity (over the concentration range 6.0×10−7 to 7.5×10−5 M, r = 0.9967), detection limit (2.0×10−7 M) and reproducibility (RSD = 4.6%, n=10, for 2.0×10−5 M Sudan I).

  15. Eocene-Pliocene stratigraphy along the southern margin of the Wind River Range, Wyoming: revisions and implications from field and fission-track studies

    SciTech Connect

    Steidtmann, J.R.; Middleton, L.T.

    1986-01-01

    The established mid-Tertiary stratigraphy along the southern margin of the Wind River Range is of questionable chronologic validity because of the difficulty in discriminating among the several tuffaceous units and because lithologic criteria have been used as chronostratigraphic indicators. Field observations and zircon fission-track ages suggest certain revisions of, and additions to, this stratigraphy. These include: (1) recognition of the Cathedral Bluffs Tongue of the Wasatch Formation at Reds Cabin monocline, (2) establishment of a late Oligocene or early Miocene age for the South Pass Formation and (3) recognition that there are middle Miocene deposits previously mapped as Arikaree that consist of reworked Arikaree shed off the upthrown side of the Continental fault. The implications of these findings are that the Continental fault, now a collapse feature, was a tear fault during the early Eocene, that there are most likely Oligocene rocks north of the Continental fault, that there was late Oligocene or early Miocene uplift in the core of the Wind River Range and that the range collapsed in the middle Miocene.

  16. Modified gulf of California model for South Georgia, north Scotia Ridge, and implications for the Rocas Verdes back-arc basin, southern Andes

    SciTech Connect

    Alabaster, T.; Storey, B.C. )

    1990-06-01

    New field mapping and an integrated trace element and Nd isotopic study have been undertaken on the Jurassic-Cretaceous Larsen Harbour Complex on the island of South Georgia, recognized as a displaced part of the southern Andes ensialic, autochthonous Rocas Verdes marginal basin. Five basalt groups (Groups I-V) are identified from trace element data; initial Nd isotopic compositions suggest that they are derived from only two sources. Magmas produced during early stages of continental lithospheric attenuation (Groups I-III) were derived by varying degrees of partial melting and fractional crystallization from a large ion lithophile element (LILE)-enriched, low-{epsilon}{sub Nd} mantle source relative to normal (N)-type mid-ocean ridge basalt (MORB). Magmas produced during later stages of rifting (Groups IV and V) were, however, derived from a high-{epsilon}{sub Nd} asthenospheric mantle source similar to N-type MORB, unaffected by earlier LILE enrichment. Our data do not occur with previous suggestions that the Larsen Harbour Complex and, by implication, the Rocas Verdes formed in a supra-subduction-zone setting. On the basis of geologic and geochemical evidence, we favor basin formation along an oblique-slip margin akin to that of the Gulf of California.

  17. Character and Implications of a Newly Identified Creeping Strand of the San Andreas fault NE of Salton Sea, Southern California

    NASA Astrophysics Data System (ADS)

    Janecke, S. U.; Markowski, D.

    2015-12-01

    The overdue earthquake on the Coachella section, San Andreas fault (SAF), the model ShakeOut earthquake, and the conflict between cross-fault models involving the Extra fault array and mapped shortening in the Durmid Hill area motivate new analyses at the southern SAF tip. Geologic mapping, LiDAR, seismic reflection, magnetic and gravity datasets, and aerial photography confirm the existence of the East Shoreline strand (ESS) of the SAF southwest of the main trace of the SAF. We mapped the 15 km long ESS, in a band northeast side of the Salton Sea. Other data suggest that the ESS continues N to the latitude of the Mecca Hills, and is >35 km long. The ESS cuts and folds upper Holocene beds and appears to creep, based on discovery of large NW-striking cracks in modern beach deposits. The two traces of the SAF are parallel and ~0.5 to ~2.5 km apart. Groups of east, SE, and ENE-striking strike-slip cross-faults connect the master dextral faults of the SAF. There are few sinistral-normal faults that could be part of the Extra fault array. The 1-km wide ESS contains short, discontinuous traces of NW-striking dextral-oblique faults. These en-echelon faults bound steeply dipping Pleistocene beds, cut out section, parallel tight NW-trending folds, and produced growth folds. Beds commonly dip toward the ESS on both sides, in accord with persistent NE-SW shortening across the ESS. The dispersed fault-fold structural style of the ESS is due to decollements in faulted mud-rich Pliocene to Holocene sediment and ramps and flats along the strike-slip faults. A sheared ladder-like geometric model of the two master dextral strands of the SAF and their intervening cross-faults, best explains the field relationships and geophysical datasets. Contraction across >40 km2 of the southernmost SAF zone in the Durmid Hills suggest that interaction of active structures in the SAF zone may inhibit the nucleation of large earthquakes in this region. The ESS may cross the northern Coachella

  18. Simulated Damping of Periodic Fluctuations in Net Infiltration Within a Thick Unsaturated Zone in Southern Nevada: Implications For Radionuclide Transport

    NASA Astrophysics Data System (ADS)

    Ebel, B. A.; Nimmo, J. R.

    2009-12-01

    Arid and semiarid regions are historically preferred sites for radionuclide generating activities and waste disposal, in part because their unsaturated zones, typically having large thickness and low water content, are expected to inhibit the transport of contaminants to groundwater supplies. Through portions of the unsaturated zone that are heavily fractured, however, there is concern that transport in preferential flow paths might be relatively rapid on an episodic basis. Even so, fractured zones are commonly interrupted by lithologic units without substantial fractures, through which unsaturated flow might always be diffuse so as to damp out episodic fluctuations. In unsaturated-zone fractured units below such damping units, the initiation of preferential flow theoretically hinges on reaching a threshold moisture state, which depends on the magnitude of pressure and flux signals resulting from natural periodic variations in net infiltration. In diffuse unsaturated flow, periodic oscillations are damped to a quasi-steady state at sufficient distance from the inflow boundary. The resulting matric potential may be insufficient to trigger or sustain fracture flow through unsaturated media lying beneath those that facilitate damping. In general, shorter-period oscillations, longer distances of diffuse flow, and drier matrix conditions are conducive to damping. In this work we examine the damping of periodic recharge signals to a quasi-steady value, using analytical solutions for diffuse unsaturated flow, at Rainier Mesa and Shoshone Mountain in southern Nevada. Underground nuclear tests in previous decades introduced radionuclides into the unsaturated subsurface at these sites. Both sites have possible damping units greater than 100 m thick that are believed to be dominated by diffuse flow. Below these damping units lie fractured rocks in which preferential flow could resume, especially if the damping units are not sufficiently thick or dry. Effective damping of

  19. Origin of the Lyme Dome and implications for the timing of multiple Alleghanian deformational and intrusive events in southern Connecticut

    USGS Publications Warehouse

    Walsh, G.J.; Aleinikoff, J.N.; Wintsch, R.P.

    2007-01-01

    Geologic mapping, structural analysis, and geochronology in the area of the Lyme dome, southern Connecticut provides constraints on the origin of the rocks in the core of the dome, the absolute timing of the principal deformational and thermal events attributed to Alleghanian orogenesis, and the processes that generated the dome. Detrital zircon geochronology in combination with ages on intrusive rocks brackets the deposition of quartzite in the core of the dome sometime between ca. 925 and 620 Ma. Granite and granodiorite intruded the Neoproteorozic metasedimentary rocks in the core of the dome at ca. 620 to 610 Ma. Four major early Permian events associated with the Alleghanian orogeny affected the rocks in the Lyme dome area. Syn-tectonic migmatization and widespread penetrative deformation (D1, ca. 300 - 290 Ma) included emplacement of alaskite at 290 ?? 4 Ma during regional foliation development and aluminosilicate-orthoclase metamorphic conditions. Rocks of the Avalon terrane may have wedged between Gander cover rocks and Gander basement in the core of the Lyme during D1. Limited structural evidence for diapiric uplift of the Lyme dome indicates that diapirism started late in D1 and was completed by D2 (ca. 290 - 280 Ma) when horizontal WNW contractional stresses dominated over vertical stresses. Second sillimanite metamorphism continued and syn-tectonic D2 granite pegmatite (288 ?? 4 Ma) and the Joshua Rock Granite Gniess (284 ?? 3 Ma) intruded at this time. North-northwest extension during D3 (ca. 280 - 275 Ma) led to granitic pegmatite intrusion along S3 cleavage planes and in extensional zones in boudin necks during hydraulic failure and decompression melting. Intrusion of a Westerly Granite dike at 275 ?? 4 Ma suggests that D3 extension was active, and perhaps concluding, by ca. 275 Ma. Late randomly oriented but gently dipping pegmatite dikes record a final stage of intrusion during D4 (ca. 275 - 260 Ma), and a switch from NNW extension to vertical

  20. Geophysical exploration of an active pockmark field in the Bay of Concarneau, southern Brittany, and implications for resident suspension feeders

    NASA Astrophysics Data System (ADS)

    Baltzer, Agnès; Ehrhold, Axel; Rigolet, Carinne; Souron, Aurélie; Cordier, Céline; Clouet, Hélène; Dubois, Stanislas F.

    2014-06-01

    About a decade ago, a large field of pockmarks (individual features up to 30 m in diameter and <2 m deep) was discovered in water depths of 15-40 m in the Bay of Concarneau in southern Brittany along the French Atlantic coast, covering an overall area of 36 km2 and characterised by unusually high pockmark densities in places reaching 2,500 per square kilometre. As revealed by geophysical swath and subbottom profile data ground-truthed by sediment cores collected during two campaigns in 2005 and 2009, the confines of the pockmark field show a spectacular spatial association with those of a vast expanse of tube mats formed by a benthic community of the suspension-feeding amphipod Haploops nirae. The present study complements those findings with subbottom chirp profiles, seabed sonar imagery and ultrasonic backscatter data from the water column acquired in April 2011. Results show that pockmark distribution is influenced by the thickness of Holocene deposits covering an Oligocene palaeo-valley system. Two groups of pockmarks were identified: (1) a group of large (>10 m diameter), more widely scattered pockmarks deeply rooted (up to 8 ms two-way travel time, TWTT) in the Holocene palaeo-valley infills, and (2) a group of smaller, more densely spaced pockmarks shallowly rooted (up to 2 ms TWTT) in interfluve deposits. Pockmark pore water analyses revealed high methane concentrations peaking at ca. 400 μl/l at 22 and 30 cm core depth in silty sediments immediately above Haploops-bearing layers. Water column data indicate acoustic plumes above pockmarks, implying ongoing pockmark activity. Pockmark gas and/or fluid expulsion resulting in increased turbidity (resuspension of, amongst others, freshly settled phytoplankton) could at least partly account for the strong spatial association with the phytoplankton-feeding H. nirae in the Bay of Concarneau, exacerbating impacts of anthropogenically induced eutrophication and growing offshore trawling activities. Tidally driven

  1. Volcanic risk and tourism in southern Iceland: Implications for hazard, risk and emergency response education and training

    NASA Astrophysics Data System (ADS)

    Bird, Deanne K.; Gisladottir, Gudrun; Dominey-Howes, Dale

    2010-01-01

    This paper examines the relationship between volcanic risk and the tourism sector in southern Iceland and the complex challenge emergency management officials face in developing effective volcanic risk mitigation strategies. An early warning system and emergency response procedures were developed for communities surrounding Katla, the volcano underlying the Mýrdalsjökull ice cap. However, prior to and during the 2007 tourist season these mitigation efforts were not effectively communicated to stakeholders located in the tourist destination of Þórsmörk despite its location within the hazard zone of Katla. The hazard zone represents the potential extent of a catastrophic jökulhlaup (glacial outburst flood). Furthermore, volcanic risk mitigation efforts in Þórsmörk were based solely on information derived from physical investigations of volcanic hazards. They did not consider the human dimension of risk. In order to address this gap and provide support to current risk mitigation efforts, questionnaire surveys were used to investigate tourists' and tourism employees' hazard knowledge, risk perception, adoption of personal preparedness measures, predicted behaviour if faced with a Katla eruption and views on education. Results indicate that tourists lack hazard knowledge and they do not adopt preparedness measures to deal with the consequences of an eruption. Despite a high level of risk perception, tourism employees lack knowledge about the early warning system and emergency response procedures. Results show that tourists are positive about receiving information concerning Katla and its hazards and therefore, the reticence of tourism employees with respect to disseminating hazard information is unjustified. In order to improve the tourism sector's collective capacity to positively respond during a future eruption, recommendations are made to ensure adequate dissemination of hazard, risk and emergency response information. Most importantly education campaigns

  2. New tectonic data from sw iberian variscan fold belt (ossa morena zone-southern portugal): implications for geodynamic models

    NASA Astrophysics Data System (ADS)

    Rosas, F.; Marques, F.; Ribeiro, A.

    2003-04-01

    New detailed structural mapping of the Alvito-Viana key sector, in SW Ossa Morena Zone (Southern Iberian Variscan Fold Belt), revealed the following tectonic imbrication of units of unknown age (from bottom to top): Gneiss unit (composed mostly of quartz-feldspar orthogneisses); Marbles unit; Água de Peixe metapelites unit (micaschists and disperse interbedded bodies - boudins? - of marbles and amphibolites); and Monte das Pereiras metapelites unit (mainly comprising micaschists and metabasalts).These units were intruded, to the North and to the West, by two main igneous complexes: the granitoid Évora massif (EM, ca. 318Ma), and the dioritic/gabbroic Beja igneous complex (BIC, ca. 340Ma), respectively. The study of metamorphic and geometric overprint relationships, between several types of structures, at different scales, revealed a chronological succession of tectonometamorphic events, comprising: a) An early high pressure metamorphic event (D_n) producing eclogites (Fonseca, et al., 1993), and blueschists (Rosas et al., in prep.). b) A retrogressive event (Dn+1 and Dn+2), affecting the HP rocks in lower grade metamorphic conditions and refolding the previous tectonic fabrics. c) A thermal event (T_n), related with an early stage of the BIC intrusions, represented by the strong static recrystallisation of the previous tectonic fabrics. d) An episode (Dn+3) represented by the tectonic reactivation of the prevoius metamorphic layering inducing a top to the NNW sense of shear. e) A N-S folding of all previous structures and fabrics as a response to the space problems imposed by the late intrusion of the BIC igneous rocks. f) A thermal episode (n+1) responsible for a late strong static recrystallisation of all previously formed tectonic fabrics, as a consequence of the granitic EM intrusions. Interpretation of this sequence of events includes the recognition, during the Variscan evolution of the SW Ossa-Morena zone, of northwards oblique subduction and HP

  3. Using Ground Penetrating Radar to Constrain the Drainage Evolution in Southern Egypt and Implications for Future Deployment on Mars

    NASA Astrophysics Data System (ADS)

    Grant, J. A.; Maxwell, T. A.; Johnston, A. K.; Leuschen, C. J.; Schutz, A. E.; Williams, K. K.

    2004-05-01

    Ground penetrating radar (GPR) constrains the origin of relict and largely buried fluvial channels in the Bir Kiseiba region of southern Egypt. GPR results indicate that the trunk channel to a tributary system identified in Shuttle Imaging Radar (SIR) data is incised 10 to 12 meters into bedrock, was southwest-draining and laterally migrating toward the northwest, and accentuated relief along the nearby Kiseiba escarpment. Alluvium partially filling the main channel likely reflects effects of increasing aridity and bed load combined with less frequent, flashier precipitation. In contrast to defining channel margins, GPR data do not indicate subtle stratigraphic changes in bedding related to fluvial aggradation, but do highlight local reflections likely corresponding to relict alluvial bar forms. These GPR data complement the SIR and field data and permit a better understanding of the evolution of this enigmatic landscape. The Egyptian study area occurs in a region long considered to possess potential analogs for landforms on Mars. GPR results from Egypt and other analog terrain combined with consideration of factors influencing radar performance on Mars instill confidence that a rover-deployed GPR can achieve 10 to 20 m penetration and provide critical constraint on geologic setting and context for other rover instruments. To take advantage of this potential, a rover-deployable impulse GPR is under development for future Mars missions and possesses mass, volume, and power limits of 0.5 kg, 3400 cc, 3 W (peak), respectively. The GPR has no moving parts, includes a body conformal antenna capable of configuration at 150 MHz to more than 600 MHz, will collect 0.3 MB data per day (assuming a 50 meter traverse), and is being successfully tested in Mars analog environments. By analogy to the results from Egypt, a Mars GPR deployed in the vicinity of valley networks should be able to distinguish diagnostic signatures required for identifying the sources of water

  4. Average Stress Drops of Southern California Earthquakes in the Context of Crustal Geophysics: Implications for Fault Zone Healing

    NASA Astrophysics Data System (ADS)

    Hauksson, Egill

    2015-05-01

    To understand how fault healing processes affect earthquake stress drops, we search for a possible dependency of stress drops on crustal conditions and geophysical parameters. We reanalyze the stress drop values of ~60,000 earthquakes in southern California which were originally determined by Shearer et al. J Geophys Res 111:B06303, (2006) using a spectral method. We modify the dataset to include only stress drops that are derived from at least 10 spectra and with corner frequencies between 3 and 30 Hz, and correct the rupture velocity for increasing S-wave speed with depth. We see no dependence of stress drop on moment magnitude or depth, except for a small, poorly determined increase from 15 to 25 km. We use six crustal geophysics parameters to search for obvious correlations that may explain changes in the mean values of the stress drops: (1) crustal thickness, (2) isostatic gravity, (3) heat flow, (4) shear strain rate, (5) crustal stress regime, and (6) style of faulting. None of the variables reduce the scatter but most can explain up to 10-20 % variations in the mean stress drops. The geographical distribution of the grouped mean stress drops includes very high stress drops near Ridgecrest, eastern California, as well as near fault jogs within the San Andreas Fault system. Low stress drops dominate in trans-tensional regions. Heat flow and GPS-based shear strain rate estimates have the largest influence on stress drop variations. In the range of low to medium heat flow, the stress drops increase with increasing heat flow. In contrast, at high heat flow in thin crust, the stress drops decrease systematically with increasing heat flow. Increasing shear strain rate systematically correlates with decreasing stress drops. The crustal stress regime and style of faulting also influence the stress drops as demonstrated by lower stress drops for north-northeast trending principal horizontal stress and in areas of dip-slip faulting. The mean variations in stress drops

  5. A temporary pond in the Early Cretaceous of southern England: palaeoclimatic implications of nonmarine "Purbeck-Wealden" ostracod faunas

    NASA Astrophysics Data System (ADS)

    Horne, D. J.

    2009-04-01

    Group in southern England. Special Papers in Palaeontology, 68, 1-18, 2 pls. Nye, E., Feist-Burkhardt, S., Horne, D. J., Ross, A. J. & Whittaker, J. E. (2008) The palaeoenvironment associated with a partial Iguanodon skeleton from the Upper Weald Clay (Barremian, Early Cretaceous) at Smokejacks Brickworks (Ockley, Surrey, UK), based on palynomorphs and ostracods. Cretaceous Research, 29, 417-444.

  6. Cholera in Sudan: An account of an epidemic in a refugee camp in eastern Sudan, May-June 1985.

    PubMed

    Malholland, K

    1985-12-01

    In 1985 cholera has been a serious problem in the horn of Africa, particularly affecting the many famine victims and refugees in that region. In this paper the history of cholera in Africa is briefly summarized, as is the background to the current refugee situation in eastern Sudan. A cholera epidemic involving 1,175 cases in two adjacent refugee camps in eastern Sudan is described. In this epidemic there were thirteen inpatient deaths and thirty-eight known home deaths from cholera. The management of the epidemic is described in detail. Overall an average of 8 1. of intravenous fluid was used per case, a higher figure than was anticipated, probably because of the unexpected degree of vomiting and the shortage of trained nursing staff. The relationship between cholera and malnutrition is explored and hypochlorhydria is suggested as the main reason for the increased susceptibility to cholera among malnourished populations. It was observed that severely malnourished adults and children appeared to nave less severe diarrhoea with their cholera, presumably because of reduced mucosal surface area and poor enterocyte function. Finally possible means of aborting cholera epidemics are discussed.

  7. Staining histological lung sections with Sudan Black B or Sudan III for automated identification of alveolar epithelial type II cells.

    PubMed

    Schneider, Jan Philipp; Pedersen, Lars; Mühlfeld, Christian; Ochs, Matthias

    2015-10-01

    Alveolar epithelial type II (AE2) cells produce, store and secrete pulmonary surfactant and serve as progenitor cells for the alveolar epithelium. They are thus an interesting target in wide fields of pulmonary research. Stereological methods allow their quantification based on measurements on histological sections. A proper AE2 cell quantification, however, requires a method of tissue processing that results in little tissue shrinkage during processing. It was recently shown that a primary fixation with a mixture of glutaraldehyde and formaldehyde, postfixation with osmium tetroxide and uranyl acetate and embedding in glycol methacrylate fulfills this requirement. However, a proper quantification, furthermore, requires a secure identification of the cells under the microscope. Classical approaches using routine stainings, high magnifications and systematic uniform random sampling can result in a tedious counting procedure. In this article we show that Sudan Black B and Sudan III staining in combination with the previously described "low shrinkage method" of tissue processing result in good staining of lamellar bodies of AE2 cells (their storing organelles of surfactant) and thus provide a good signal of AE2 cells, which allows their easy and secure identification even at rather low magnifications. We further show that this signal enables automated detection of AE2 cells by image analysis, which should make this method a suitable staining method for the recently developed and more efficient proportionator sampling. PMID:26558990

  8. Tectono-thermal History of the Southern Nenana Basin, Interior Alaska: Implications for Conventional and Unconventional Hydrocarbon Exploration

    NASA Astrophysics Data System (ADS)

    Dixit, N. C.; Hanks, C. L.

    2014-12-01

    The Tertiary Nenana basin of Interior Alaska is currently the focus of both new oil exploration and coalbed methane exploitation and is being evaluated as a potential CO2sequestration site. The basin first formed as a Late Paleocene extensional rift with the deposition of oil and gas-prone, coal-bearing non-marine sediments with excellent source potential. Basin inversion during the Early Eocene-Early Oligocene times resulted in folding and erosion of higher stratigraphic levels, forming excellent structural and stratigraphic traps. Initiation of active faulting on its eastern margin in the middle Oligocene caused slow tectonic subsidence that resulted in the deposition of reservoir and seal rocks of the Usibelli Group. Onset of rapid tectonic subsidence in Pliocene that continues to the present-day has provided significant pressure and temperature gradient for the source rocks. Apatite fission-track and vitrinite reflectance data reveals two major paleo-thermal episodes: Late Paleocene to Early Eocene (60 Ma to 54.8 Ma) and Late Miocene to present-day (7 Ma to present). These episodes of maximum paleotemperatures have implications for the evolution of source rock maturity within the basin. In this study, we are also investigating the potential for coalbed methane production from the Late Paleocene coals via injection of CO2. Our preliminary analyses demonstrate that 150 MMSCF of methane could be produced while 33000 tonnes of CO2 per injection well (base case of ~9 years) can be sequestered in the vicinity of existing infrastructure. However, these volumes of sequestered CO2and coal bed methane recovery are estimates and are sensitive to the reservoir's geomechanical and flow properties. Keywords: extensional rift, seismic, subsidence, thermal history, fission track, vitrinite reflectance, coal bed methane, Nenana basin, CO2 sequestration

  9. Minerals and trace elements in silcretes of the Sado basin (Alentejo, southern Portugal) and implications for silcrete formation

    NASA Astrophysics Data System (ADS)

    Sauer, Daniela; Kullmann, Sarah; Zarei, Mehdi; Stahr, Karl

    2014-05-01

    Soils in the eastern part of the Sado basin (southern Portugal) are often characterized by massive cementations caused by silica. The thickness and massive character of these silcretes led to the hypothesis that accumulation of silica took place not only vertically within a soil profile, but also by enrichment through lateral water and element flow into the Sado basin. The aims of the study reported here were: 1) to characterize the cementing agent with regard to its mineralogy; 2) to test the hypothesis that silification was enhanced through lateral silica transport from the adjacent Alto Alentejo into the Sado basin. Aim 1) was achieved by scratching silica coatings from ped surfaces of the silicified soil horizons and cleaning them manually in the lab under a binocular microscope. After careful smashing with a mortar, density separation by sodium polytungstate solution was applied to remove any remaining mineral grains from the silica samples. The cleaned silica samples were then subjected to XRD and SEM in combination with EDS. Aim 2) was attained by using trace element contents of predominant rock types of the Alto Alentejo and of the silcretes in the Sado basin for identifying lateral pathways of water and silica in the landscape. Ten rock samples from the assumed source area of silica were combusted by fusion melt, and their contents of Ba, Co, Cs, Nb, Pb, Rb, Sr, Y and Zr were analyzed by ICP-MS. The same elements were analyzed in NaOH extracts of the cemented soil horizons in the Sado basin. The X-ray diagrams of the silica coatings show the expected broad hump of amorphous silica. In addition, quartz, kaolinite, and surprisingly high amounts of halloysite are identified, the latter reflecting conditions of intensive weathering and pedogenesis during the formation of the silica coatings. This intensive soil formation and hence silification most likely took place during Pliocene. Greater age is impossible, because the silification took place in Pliocene

  10. Environmental Magnetism of Late Quaternary Sediments From the Southern Okinawa Trough: Paleoceanographic Implications and History of the Kuroshio Current

    NASA Astrophysics Data System (ADS)

    Richter, C.; Venuti, A.; Verosub, K. L.; Wei, K.

    2008-12-01

    The objective of this study is to advance our understanding of the late Cenozoic environmental and paleoceanographic history of the Southern Okinawa Trough and the Kuroshio Current. Our investigation is based on the environmental magnetic record of a suite of u-channel samples that span the upper 140 m (0.42 m.y.) of ODP Site 1202. This site was drilled in the southernmost Okinawa Trough off the northeast coast of Taiwan and provides, with sedimentation rates of up to 9 m/k.y., one of the highest-resolution records of environmental and paleoceanographic change ever recovered. Variations in the concentration of fine-grained magnetite (anhysteretic remanent magnetization, ARM), magnetic grain size (ARM/k), magnetic hardness (ARM(30)/ARM(0)), and overall mineralogy (susceptibility, k) reflect fluctuations in climate, sea level, source material, and depositional environment. Eleven AMS C-14 dates of planktonic foraminifers and scaphopod samples combined with oxygen isotope stratigraphy (Wei et al., 2005) provide a relatively low- resolution, but well-defined age model. Based on the magnetic characteristics we distinguished five distinctive intervals with boundaries at 11.3, 14.3, 18.6, and 27.4 ka. From the beginning of the record at about 40 ka to 27.4 ka (MIS-3) all magnetic parameters remain remarkably constant indicating very little variation in sediment source and processes. Sea level during this time interval fluctuated at around -80 m. At 27.4 ka a significant decrease in magnetic grain size is accompanied by an increase in the amount of magnetic material. This change coincides with a drop in sea level below -80 m in the buildup to the sea level lowstand of the Last Glacial Maximum (LGM). Sediment source during this time interval was predominantly the East China Sea (Wei, 2006; Diekmann et al., in press). MIS-2 is characterized by constantly increasing magnetic grain size and a decreasing amount of magnetic material. At 14.3 ka after melt water pulse (MWP) 1A

  11. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE... reexportation, directly or indirectly, to Sudan of any goods, technology (including technical data, software,...

  12. Large Glacitectonic structures on the Dogger Bank, southern North Sea; Implications for glacial dynamics, glacial limits, and interplay between the British and Fennoscandinavian Ice Sheets

    NASA Astrophysics Data System (ADS)

    Dove, Dayton; Cotterill, Carol; Long, Dave; Ruiter, Astrid; Phillips, Emrys; James, Leo; Forsberg, Carl Fredrik

    2013-04-01

    caused by sub-glacial (gravitational spreading), ice-marginal (push-moraine complex), or pro-glacial (ice-push) processes, or a combination of the three at an oscillating ice-margin. The thrusts appear to have no surface expression, suggesting the topography was removed either by late-stage glacial erosion or Holocene marine transgression. Work to date on the paleoenvironmental implications of the data has been preliminary. The exact style, pattern, and timing glacial deformation (and associated sedimentation) on the Dogger Bank and circum-southern North Sea, and glacial history of the region, will be the focus of a Ph.D studentship which commenced Sept. 2012.

  13. Characterization of a new cucurbit-infecting ipomovirus from Sudan.

    PubMed

    Desbiez, Cécile; Verdin, Eric; Tepfer, Mark; Wipf-Scheibel, Catherine; Millot, Pauline; Dafalla, Gasim; Lecoq, Hervé

    2016-10-01

    Two members of the genus Ipomovirus (family Potyviridae) are known to infect cucurbits: cucumber vein yellowing virus (CVYV), which is emerging throughout the Mediterranean Basin, and squash vein yellowing virus (SqVYV), which has been described in America and the Caribbean Basin, and more recently in Israel. In this work, an ipomovirus different from CVYV and SqVYV, tentatively named coccinia mottle virus (CocMoV), was detected in a sample of the cucurbit Coccinia grandis collected in central Sudan in 2012. Sequence identity in nt was 68 % with CVYV, 59-60 % with SqVYV, cassava brown streak virus and Ugandan cassava brown streak virus, and less than 50 % with other members of the family Potyviridae. Preliminary biological and epidemiological studies indicate that CocMoV has a narrow natural host range and a low prevalence. PMID:27430562

  14. Peste des petits ruminants outbreaks in White Nile State, Sudan.

    PubMed

    Ishag, Osama M; Saeed, Intisar K; Ali, Yahia H

    2015-01-01

    Eight outbreaks of peste des petits ruminants in sheep and goats were reported in White Nile State, Sudan, between 2008 and 2009. A mortality rate of 4.2% was reported across the different outbreaks. Clinically the disease was characterised by high fever, ocular and nasal discharge, pneumonia, ulceration of the mucous membranes, diarrhoea and death. The postmortem findings included necrotic lesions in the mouth and gastrointestinal tract, and swollen, oedematous lymph nodes associated with the lungs and intestine. Of the 209 serum samples tested by competitive enzyme-linked immunosorbent assay, 113 (54%) were found positive. Peste des petits ruminants virus was confirmed in tissues, nasal swabs and blood samples by immunocapture enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction and isolation of the virus in culture of lamb testicle cells. PMID:26304168

  15. Tectonostratigraphic development of the Interior Sudan rifts, Central Africa

    NASA Astrophysics Data System (ADS)

    McHargue, Tim R.; Heidrick, Tom L.; Livingston, Jack E.

    1992-10-01

    In the Muglad, Melut and Blue Nile rift basins of Interior Sudan three major episodes of rifting, concomitant subsidence and nonmarine/nonvolcanic sedimentation are recognized. These three rifting cycles, which spanned 140 to 95 Ma (Fl), 95 to 65 Ma (F2), and 65 to 30 Ma (F3), resulted in the accumulation of up to 5400, 4200 and 5400 m of sediments, respectively. In the Muglad Basin, the best known and largest of the Sudan rift basins, each rifting cycle consists of (1) a basal sandstone unit (at least near rift margins), that is followed by (2) an upward coarsening section of lacustrine shale grading through marginal lacustrine mudstone and sandstone into fluvial mudstone and sandstone, and (3) a capping blanket of fluvial and alluvial sandstone. The shale-dominated portions of these cycles were deposited in a closed-drainage basin during active faulting. The fluvial and alluvial blanket sands were deposited in an open-drainage basin during the thermal sag phase following each tectonic cycle. The Early Cretaceous F1 intracontinental rifts of Interior Sudan were linked to major rifts/spreading centres in the Proto-South Atlantic by the dextral WSW-trending Central African Shear Zone and to the Indian Ocean via the NW-trending Anza rift in Kenya. In the Muglad Basin, F1 deformation involved high strain rates, rapid syn-rift crustal stretching and subsidence, and the formation of deep, fault-bounded tensional and transtensional pull-apart basins. During the F2 and F3 deformations, the rates of subsidence and stretching were much lower and were focused within smaller geographic areas. Structural elements include asymmetric half-grabens and less common full-grabens with central highs. The three superimposed tectonic episodes resulted in the subsidence of NNW- to NW-trending rift sub-basins; this gave rise to a wide variety of normal fault geometries, displacements, and growth histories. Planar domino-style and listric normal F1 fault arrays are modeled. The rotated F1

  16. Peste des petits ruminants outbreaks in White Nile State, Sudan.

    PubMed

    Ishag, Osama M; Saeed, Intisar K; Ali, Yahia H

    2015-08-21

    Eight outbreaks of peste des petits ruminants in sheep and goats were reported in White Nile State, Sudan, between 2008 and 2009. A mortality rate of 4.2% was reported across the different outbreaks. Clinically the disease was characterised by high fever, ocular and nasal discharge, pneumonia, ulceration of the mucous membranes, diarrhoea and death. The postmortem findings included necrotic lesions in the mouth and gastrointestinal tract, and swollen, oedematous lymph nodes associated with the lungs and intestine. Of the 209 serum samples tested by competitive enzyme-linked immunosorbent assay, 113 (54%) were found positive. Peste des petits ruminants virus was confirmed in tissues, nasal swabs and blood samples by immunocapture enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction and isolation of the virus in culture of lamb testicle cells.

  17. The Impact of Conflict on Forests in South Sudan

    NASA Astrophysics Data System (ADS)

    Gorsevski, V.; Kasischke, E. S.; Dempewolf, J.; Loboda, T. V.; Geores, M.

    2014-12-01

    The impacts of armed conflict on ecosystems are complex and difficult to assess due to restricted access to affected areas making satellite remote sensing a useful tool for studying direct and indirect effects of conflict on the landscape. The Imatong Central Forest Reserve (ICFR) in South Sudan together with the nearby Dongotana Hills and the Agoro-Agu Forest Reserve (AFR) in Northern Uganda share a boundary and encompass a biologically diverse montane ecosystem. This study used satellite data combined with general human population trends to examine the impact of armed conflict and its outcome on similar forest ecosystems both during and after hostilities. A Disturbance Index (DI) was used to investigate the location and extent of forest cover loss and gain in three areas for two key time periods. Results indicate that the rate of forest recovery was significantly higher than the rate of disturbance both during and after wartime in and around the ICFR. In contrast, the nearby Dongotana Hills experienced relatively high rates of disturbance during both periods; however, post war period losses were largely offset by some gains in forest cover. Discussions with local inhabitants confirmed these findings and provided further insights into the underlying causes impacting forest cover and wildlife. South Sudan is the latest nation to join the Global Environment Facility (GEF). While the GEF does not explicitly address conflict, many of the projects it supports occur in conflict and post-conflict zones with wide-ranging repercussions for both people and the environment. In an effort to assess best practices for working in conflict and post-conflict areas, the GEF Scientific and Technical Advisory Panel (STAP) will undertake an analysis of GEF-funded projects over the last two decades to identify where the GEF has promoted cooperation between groups and states, and/or made a positive contribution toward conflict avoidance resulting in shared environmental benefits.

  18. a Regional Study of Seasonal Rainfall Conditions in the Sudan

    NASA Astrophysics Data System (ADS)

    El Seed, Abdel Malik Gasm

    Available from UMI in association with The British Library. This thesis is primarily a regional climatological study of some spatial and temporal rainfall characteristics, with a special emphasis being made on quantitative analysis of the wet season rains over the Sudan. The study area has been objectively classified into five main "rainfall regions" on the basis of wet season duration and timing at 60 observing stations. Also a regionalisation derived from two multivariate techniques is compared and critically discussed. The spatial distributions of mean wet and dry season rainfall over individual regions, are described and explained by reference to the main weather systems and topographic features using the method of trend surface analysis. Rainfall variability has been quantified by the coefficient of variation index and analysed in a similar way to that of rainfall distribution. The results have shown an inverse relationship between variability indices and mean rainfall amounts. In relation to the study of variability, an assessment of rainfall probability and reliability has been discussed with reference to certain critical rainfall amounts and by applying the concept of binomial frequency distribution for critical time periods. The spatial distribution of mean rain days tends to portray a similar pattern to that of the mean rainfall. This apparent relationship is confirmed by the highly significant correlation coefficients between the two parameters. The relation between mean rainfall and daily rainfall intensity is not always a direct one, since wetter areas are mostly associated with increased frequency of rain days rather than greater rainfall intensities. Daily rainfall analysis has also revealed that the probability distributions of wet and dry spells of various sequence lengths can be mathematically derived from a Markov chain model and these were found to fit the actual daily data closely. Finally, the contributions of various atmospheric factors to

  19. 78 FR 68500 - In the Matter of the Designation of Jama'atu Ansarul Muslimina Fi Biladis-Sudan Also Known as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... as Ansarul Muslimina Fi Biladis Sudan Also Known as Vanguards for the Protection of Muslims in Black... known as Ansarul Muslimina Fi Biladis Sudan, also known as Vanguards for the Protection of Muslims...

  20. Evaluation of impact of exposure of Sudan azo dyes and their metabolites on human intestinal bacteria.

    PubMed

    Pan, Hongmiao; Feng, Jinhui; He, Gui-Xin; Cerniglia, Carl E; Chen, Huizhong

    2012-08-01

    Sudan azo dyes are banned for food usage in most countries, but they are illegally used to maintain or enhance the color of food products due to low cost, bright staining, and wide availability of the dyes. In this report, we examined the toxic effects of these azo dyes and their potential reduction metabolites on 11 prevalent human intestinal bacterial strains. Among the tested bacteria, cell growth of 2, 3, 5, 5, and 1 strains was inhibited by Sudan I, II, III, IV, and Para Red, respectively. At the tested concentration of 100 μM, Sudan I and II inhibited growth of Clostridium perfringens and Lactobacillus rhamnosus with decrease of growth rates from 14 to 47%. Sudan II also affected growth of Enterococcus faecalis. Growth of Bifidobacterium catenulatum, C. perfringens, E. faecalis, Escherichia coli, and Peptostreptococcus magnus was affected by Sudan III and IV with decrease in growth rates from 11 to 67%. C. perfringens was the only strain in which growth was affected by Para Red with 47 and 26% growth decreases at 6 and 10 h, respectively. 1-Amino-2-naphthol, a common metabolite of the dyes, was capable of inhibiting growth of most of the tested bacteria with inhibition rates from 8 to 46%. However, the other metabolites of the dyes had no effect on growth of the bacterial strains. The dyes and their metabolites had less effect on cell viability than on cell growth of the tested bacterial strains. Clostridium indolis and Clostridium ramosum were the only two strains with about a 10 % decrease in cell viability in the presence of Sudan azo dyes. The present results suggested that Sudan azo dyes and their metabolites potentially affect the human intestinal bacterial ecology by selectively inhibiting some bacterial species, which may have an adverse effect on human health.

  1. Education in Emergencies and Early Reconstruction: UNICEF Interventions in Colombia, Liberia, and Southern Sudan

    ERIC Educational Resources Information Center

    Beleli, Ozsel; Chang, Victoria; Feigelson, Michael J.; Kopel-Bailey, Jules A.; Maak, Sheila A.; Mnookin, Jacob P.; Nguyen, Thu H.; Salazar, Mariana; Sinderbrand, Joy E.; Tafoya, Simon N.

    2007-01-01

    Broad access to quality, child-friendly education in emergencies is a critical component of early reconstruction and development. As a class of graduate students at the Woodrow Wilson School of Public and International Affairs at Princeton University, our goal is to make a modest contribution to the field of education in emergencies by working…

  2. Studies on the livestock of southern Darfur, Sudan. III. Production traits in sheep.

    PubMed

    Wilson, R T

    1976-05-01

    The results of an intensive 15 months' study of 10 flocks of indigenous sheep are recorded. Lambing rates approach 1.5 lambs per ewe per year, but a death rate of 23 per cent and an offtake of 27 per cent, means that flock numbers are probably slightly declining. Twins account for 14 per cent of all births but the death rate of twin lambs is almost twice that of single lambs up to 6 months of age. Increased productivity is therefore more likely to be achieved by improving the survival and growth rates of single lambs than by selection for twinning. The weighted average rate of lightweight gain for all surviving lambs is 82 g per day up to 1 year of age, and is better than that recorded for any other indigenous African sheep. Meat production per kg of breeding female, at 0.253 kg up to 6 months of age of the young, is almost six times the production of cattle under the same management and environmental conditions, but is inferior to that of goats.

  3. International Aid as Informal Educator: Exploring Political Attitudes and Engagement in Southern Sudan

    ERIC Educational Resources Information Center

    Pagen, Christine Mary

    2010-01-01

    Scholarship has isolated internal economic conditions and political institutions as essential factors in political development and democracy-building, this research suggests that external influences are at play. During times of civil war and post-conflict reconstruction, governmental and socioeconomic structures are likely weak or nonexistent, and…

  4. Infants in Juba, southern Sudan: the first twelve months of life.

    PubMed

    Woodruff, A W; Adamson, E A; Suni, A E; Maughan, T S; Kaku, M; Bundru, N

    1984-09-01

    A prospective survey of child health in Juba has been continued till the infants were 12 months old. They were visited monthly or more often if unwell. During the second 6 months of life 6 died; these deaths added to the 9 which occurred in the first 6 months produced an infant mortality rate of 11.8%. Diarrhoea was the whole or a partial cause of 11 of the 15 deaths in the first year. Growth in length by 12 months was satisfactory but the mean weight of the study infants was then at the third centile for healthy girls. Head circumference at 12 months was below normal and poor development was associated with the smaller head circumferences. Supplementary feeding had been started for all babies by the 12th month but only 4 of 127 had been weaned. 30 documented attacks of diarrhoea took place before supplementary feeding was started, suggesting that water given to infants is often contaminated.

  5. Preparation of anti-Sudan red monoclonal antibody and development of an indirect competitive enzyme-linked immunosorbent assay for detection of Sudan red in chilli jam and chilli oil.

    PubMed

    Xu, Jing; Zhang, Yuanyang; Yi, Jian; Meng, Meng; Wan, Yuping; Feng, Caiwei; Wang, Shanliang; Lu, Xiao; Xi, Rimo

    2010-10-01

    Sudan dyes are banned to be used in food additives because of the carcinogenicity of their metabolites. A rapid and sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed to detect the residues of Sudan dyes. Novel immunogen and coating antigen were synthesized via glutaraldehyde linking. The hapten-bovine serum albumin (BSA) was applied as immunogen and the hapten-ovalbumin (OVA) was served as coating antigen. The monoclonal antibody obtained showed high sensitivity to Sudan I with an IC(50) value of 1.7 μg L(-1) in buffer and was suitable to detect the residues of Sudan red in food products. The specificity of the assay was studied by measuring cross-reactivity of the antibody with the structurally related compounds of Sudan II (<1%), Sudan IV (<1%) and para red (120%). Chilli jam and chilli oil samples spiked with Sudan dyes were analyzed by the method. The detection limit (LOD) of the ELISA method applied in chilli jam and chilli oil was 9.0 μg L(-1) and 19.6 μg L(-1), respectively. The recovery rates of Sudan-I in chilli oil and chilli jam were in the range of 80%-110% with coefficients of variation <25%. The intra-assay variation and inter-assay variation in buffer were both <9%.

  6. Mapping Extensional Structures in the Makgadikgadi Pans, Botswana with remote sensing and aeromagnetic data: Implication for the continuation of the East African Rift System in southern Africa

    NASA Astrophysics Data System (ADS)

    Fetkovich, E. J.; Atekwana, E. A.; Abdelsalam, M. G.; Atekwana, E. A.; Katumwehe, A. B.

    2015-12-01

    We used Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) and aeromagnetic data to map extensional structures in the Makgadikgadi Pans in northeastern Botswana. These pans are a major morphological feature in Southern Africa characterized by the presence of low lying and flat topography with the highest elevation of 945 m. This topography was a result of multiple filling and desiccation of paleo-lakes that accompanied alternation of wetter and dryer climate during the Late Quaternary period. The objective of our study was to map the extent and distribution of normal faults using their morphological expression and magnetic signature, and examine their relationship with paleo-shorelines of the pans. We: (1) Created a hill shade relief map from the SRTM DEM; (2) Extracted regional NW-SE trending topographic profiles across the pans; (3) Constructed displacement profiles for major normal faults; and (4) Created tilt derivative images from the aeromagnetic data. We found that: (1) The northeastern part of the pan is dissected by three morphologically-defined NE-trending normal faults. The along strike continuity of these faults is in the range of 75 and 170 km and they are spaced at ~30 km apart from each other. (2) The topographic profiles suggest that the exposed minimum vertical displacement (EMVD), defined by poorly developed escarpments, is in the range of 0 m and 49 m. (3) The displacement profiles of the faults is characterized by maximum EMVD in the middle of the faults and that it decays towards the fault tips. These faults are also apparent in the aeromagnetic maps where they seem to displace E-W trending Karoo-age dikes. (4) At least the outer paleo-shoreline of the pans is modified by the NE-trending faults. This suggests that the faults are younger than the paleo-shorelines, which is suggested to have been developed between 500 and 100 ka. Traditionally, the southwestern extension of the East African Rift System has been assigned to the

  7. Hydrological, socio-economic and reservoir alterations of Er Roseires Dam in Sudan.

    PubMed

    Alrajoula, Mohammad Taher; Al Zayed, Islam Sabry; Elagib, Nadir Ahmed; Hamdi, Moshrik R

    2016-10-01

    Er Roseires Dam plays a key role in controlling the Blue Nile flow in Sudan. This study explores the influence of the dam on the hydrological regimes, which in turn have implications for the ecosystem. The Range of Variability Approach (RVA) - based on a set of 32 indicators - was applied over the period 1965 to 2014 to establish a safe range of river flow. Moreover, remotely-sensed data of the Normalized Difference Vegetation Index (NDVI) was used to analyse the spatio-temporal variation of the dam's reservoir area over the period 2000-2014. Significant influence on the dry-season hydrological indicators is expressed by high negative hydrological alteration of the range from -47% to -100%, but the dam contributes positively through flow regulation during the flood season. Impounding water procedure and fluctuation of water flow caused by the dam are found to induce significant alterations. Releasing less water during the dry season and more gradual impounding process, which are not expected to affect the power generation or irrigation practices, are recommended for better ecological restoration. The total surface area of the reservoir has changed post the implementation of the dam heightening project. Since 2012, the lake surface area has expanded by 250%. Relationships between the lake size and the head have been developed to help in the monitoring of the hydrological conditions and, accordingly, in managing the dam operation. A field survey showed that the dam plays a positive social role as the reservoir supports local activities, such as fishery, farming, and collection of wood and fruits. But increased humidity and health problems have also been noted. The Grand Ethiopian Renaissance Dam (GERD) would have a direct effect on Er Roseires Dam and the river flow downstream. High level of coordination among the riparian countries is recommended for better river water management. PMID:27288976

  8. Sudan dyes in adulterated saffron (Crocus sativus L.): Identification and quantification by (1)H NMR.

    PubMed

    Petrakis, Eleftherios A; Cagliani, Laura R; Tarantilis, Petros A; Polissiou, Moschos G; Consonni, Roberto

    2017-02-15

    Saffron, the dried red stigmas of Crocus sativus L., is considered as one of the most expensive spices worldwide, and as such, it is prone to adulteration. This study introduces an NMR-based approach to identify and determine the adulteration of saffron with Sudan I-IV dyes. A complete (1)H and (13)C resonance assignment for Sudan I-IV, achieved by two-dimensional homonuclear and heteronuclear NMR experiments, is reported for the first time. Specific different proton signals for the identification of each Sudan dye in adulterated saffron can be utilised for quantitative (1)H NMR (qHNMR), a well-established method for quantitative analysis. The quantification of Sudan III, as a paradigm, was performed in varying levels (0.14-7.1g/kg) by considering the NMR signal occurring at 8.064ppm. The high linearity, accuracy and rapidity of investigation enable high resolution (1)H NMR spectroscopy to be used for evaluation of saffron adulteration with Sudan dyes.

  9. Sudan dyes in adulterated saffron (Crocus sativus L.): Identification and quantification by (1)H NMR.

    PubMed

    Petrakis, Eleftherios A; Cagliani, Laura R; Tarantilis, Petros A; Polissiou, Moschos G; Consonni, Roberto

    2017-02-15

    Saffron, the dried red stigmas of Crocus sativus L., is considered as one of the most expensive spices worldwide, and as such, it is prone to adulteration. This study introduces an NMR-based approach to identify and determine the adulteration of saffron with Sudan I-IV dyes. A complete (1)H and (13)C resonance assignment for Sudan I-IV, achieved by two-dimensional homonuclear and heteronuclear NMR experiments, is reported for the first time. Specific different proton signals for the identification of each Sudan dye in adulterated saffron can be utilised for quantitative (1)H NMR (qHNMR), a well-established method for quantitative analysis. The quantification of Sudan III, as a paradigm, was performed in varying levels (0.14-7.1g/kg) by considering the NMR signal occurring at 8.064ppm. The high linearity, accuracy and rapidity of investigation enable high resolution (1)H NMR spectroscopy to be used for evaluation of saffron adulteration with Sudan dyes. PMID:27664653

  10. Microsatellite markers reveal high genetic diversity in date palm (Phoenix dactylifera L.) germplasm from Sudan.

    PubMed

    Elshibli, Sakina; Korpelainen, Helena

    2008-10-01

    Genetic diversity in date palm germplasm from Sudan representing 37 female and 23 male accessions was investigated using 16 loci of microsatellite (SSR) primers. Eight female accessions from Morocco were included as reference material. The tested SSR markers showed a high level of polymorphism. A total of 343 alleles were detected at the 16 loci. The number of alleles per marker ranged from 14 to 44 with an average of 21.4 per locus. A high level of expected heterozygosity was observed among Sudan cultivars (0.841), Morocco cultivars (0.820) and male accessions (0.799). The results indicate that the genetic groups of the Sudan cultivars and/or males do not follow a clear geographic pattern. However, the morocco group showed significant differentiation in relation to the Sudan groups, as measured by F (ST) values and genetic distances. The effect of the methods of pollination and cultivar selection on the genetic structure was clearly detected by the weak clustering association that was observed for the majority of accessions originating from Sudan and Morocco as well. This suggests the need for further investigation on the genetic diversity of Sudanese date palm germplasm. A deeper insight will be revealed by a detailed analysis of populations originating from different geographic locations.

  11. A review of analytical techniques for determination of Sudan I-IV dyes in food matrixes.

    PubMed

    Rebane, Riin; Leito, Ivo; Yurchenko, Sergei; Herodes, Koit

    2010-04-23

    Sudan dyes are a family of lipophilic azo dyes, extensively used in industrial and scientific applications but banned for use as food colorants due to their carcinogenicity. Due to the continuing illicit use of Sudan dyes as food colorants their determination in different food matrices--especially in different chilli and tomato sauces and related products--has during the recent years received increasing attention all over the world. This paper critically reviews the published determination methods of Sudan I-IV dyes. LC-UV-vis and LC-MS are the dominating methods for analysis of Sudan I-IV dyes. Sudan dyes are usually found in food at mg kg(-1) levels at which it may be necessary to use a preconcentration step in order to attain the desired detection limits. Liquid-solid extraction is the dominating sample preparation procedure. In recent years it has been supplemented by ultrasonic-assisted extraction and pressurized liquid extraction. Various solid phase extraction types have been used for sample cleanup. The large majority of works use conventional C18 columns and conventional LC eluents. Traditionally the UV-vis absorbance detection has been the most frequently used. In the recent years MS detection is applied more and more often as it offers more reliable identification possibilities.

  12. 76 FR 63635 - Extension of the Designation of Sudan for Temporary Protected Status and Automatic Extension of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... extraordinary and temporary conditions within that country. See 62 FR 59737; section 244(a)(b)(1)(A), (C) of the... redesignated Sudan for TPS a total of 12 times, including this extension. See 74 FR 69355 (Dec. 31, 2009.... 69 FR 60168 (Oct. 7, 2004). The last extension of TPS for Sudan was announced on December 31,...

  13. The Relationship between Leadership Style and Motivation among Faculty Members in Two Public Universities in the Republic of South Sudan

    ERIC Educational Resources Information Center

    Malok, Malok N.

    2012-01-01

    The purpose of this study was to investigate the relationship between leadership style and motivation among faculty members in two public universities in the Republic of the South Sudan. The researcher examined this issue by surveying and interviewing faculty members in two public universities in the Republic of South Sudan, a total of 67 for…

  14. Development and validation of a confirmatory HPLC method for simultaneous determination of Sudan dyes in animal tissues and eggs.

    PubMed

    Wu, Yin-Liang; Li, Cun; Xia, Xi; Liu, Yong-Jun; Shen, Jian-Zhong

    2010-01-01

    A simple and sensitive high-performance liquid chromatography (HPLC) analytical method for the simultaneous determination of six Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B, Sudan IV) in animal tissues and eggs was developed. Samples were extracted with acetonitrile followed by a cleanup using a C(18) solid-phase extraction column. Chromatographic separation was achieved on a Zorbax SB-C(18) column under gradient conditions. The analytes were detected at 510 nm by HPLC with diode array detection. Specificity, decision limit (CCalpha), detection capacity (CCbeta), accuracy, and precision were determined during validation process. Recoveries for six Sudan dyes from three animal tissues and eggs were 77.2-98.0% with excellent relative standard deviations. CCalpha and CCbeta were in the range of 7.7-9.0 microg/kg and 9.1-10.3 microg/kg, respectively. The limits of quantitations were between 12.8 microg/kg and 15.0 microg/kg.

  15. Cystic echinococcosis in Mundari tribe-members of South Sudan

    PubMed Central

    Stewart, Barclay T; Jacob, Joseph; Finn, Timothy; Lado, Mounir; Napoleon, Robert; Brooker, Simon; Sidhu, Paul S; Kolaczinski, Jan

    2013-01-01

    Many neglected tropical diseases, including the zoonotic disease cystic echinococcosis (hydatidosis), are endemic to East Africa. However, their geographical distribution is heterogenous and incompletely characterized. The aim of this study was to determine if Mundari pastoralists harbor endemic human hydatidosis. The survey was conducted in cattle camps randomly selected from accessible sites provided by officials in Terekeka, South Sudan. Following informed consent, a questionnaire collected demographic data and hydatid exposure risk. A systematic sonographic abdominal exam was performed using General Electric’s LOGIQ Book XP with a 3C-RS 2–5 MHz curvilinear transducer. Six hundred and ten individuals were screened from 13 camps. Four infections were identified, all in women. The prevalence of abdominal hydatid disease in the Mundari tribe-members in cattle camps was 0.7% and all individuals reporting at least one high-risk exposure to hydatid disease. Cystic echinococcosis is endemic among Mundari pastoralists; however, it would appear to be less endemic than in neighboring tribes. PMID:24139620

  16. Epidemiology of Substance Use among University Students in Sudan

    PubMed Central

    Osman, Tarig; Victor, Cathrine; Abdulmoneim, Alaa; Mohammed, Hala; Abdalla, Fatima; Ahmed, Asma; Ali, Eiman; Mohammed, Wael

    2016-01-01

    Background. Youth populations are vulnerable to substance use particularly in developing countries where circumstances may be favorable for it. There is no published data on substance use among the youth in Sudan other than on tobacco use. Objectives. The aim of this study was to investigate the prevalence, circumstances, and factors associated with substance use. Methods. An institution-based survey was conducted on a sample of 500 students. Data was collected using a questionnaire designed by the WHO for student drug surveys and analyzed using IBM SPSS version 20. Results. The overall prevalence of substance use is 31%. The current prevalence of tobacco, cannabis, alcohol, amphetamines, tranquilizers, inhalants, opiates, cocaine, and heroin use was 13.7%, 4.9%, 2.7%, 2.4%, 3.2%, 1%, 1.2%, 0.7%, and 0.5%, respectively. Curiosity (33.1%) was the main reason for initiation of substance use. The main adverse effects reported were health problems (19.7%) and theft (19.7%). Peers (40.9%) were the prime source of substance use. On multivariate analysis, male sex was the principle predictor for substance use (AOR: 5.55; 95% CI: 3.38, 9.17). Conclusion. Strategies to control substance use should encompass the role of the university and parents in observing and providing education to improve awareness of substances and their consequences. PMID:27006856

  17. Epidemiology of Substance Use among University Students in Sudan.

    PubMed

    Osman, Tarig; Victor, Cathrine; Abdulmoneim, Alaa; Mohammed, Hala; Abdalla, Fatima; Ahmed, Asma; Ali, Eiman; Mohammed, Wael

    2016-01-01

    Background. Youth populations are vulnerable to substance use particularly in developing countries where circumstances may be favorable for it. There is no published data on substance use among the youth in Sudan other than on tobacco use. Objectives. The aim of this study was to investigate the prevalence, circumstances, and factors associated with substance use. Methods. An institution-based survey was conducted on a sample of 500 students. Data was collected using a questionnaire designed by the WHO for student drug surveys and analyzed using IBM SPSS version 20. Results. The overall prevalence of substance use is 31%. The current prevalence of tobacco, cannabis, alcohol, amphetamines, tranquilizers, inhalants, opiates, cocaine, and heroin use was 13.7%, 4.9%, 2.7%, 2.4%, 3.2%, 1%, 1.2%, 0.7%, and 0.5%, respectively. Curiosity (33.1%) was the main reason for initiation of substance use. The main adverse effects reported were health problems (19.7%) and theft (19.7%). Peers (40.9%) were the prime source of substance use. On multivariate analysis, male sex was the principle predictor for substance use (AOR: 5.55; 95% CI: 3.38, 9.17). Conclusion. Strategies to control substance use should encompass the role of the university and parents in observing and providing education to improve awareness of substances and their consequences. PMID:27006856

  18. Women's experiences in the armed conflict situation in Sudan.

    PubMed

    1999-01-01

    The negative impact of war is apparent at various levels of the Sudanese society. Economic, social, and political instability is occurring on a large scale and the most vulnerable groups are women and children. This report aimed to document women's human rights violations in the ongoing armed conflict situation in Sudan, with the emphasis on rape; investigate the forms of violence against women in a situation of armed conflict; present testimonies of women survivors; and use the document for advocacy. A total of 20 testimonies were obtained, which clearly indicated that rape is a systematic practice in areas of conflict regardless of whether the Sudanese People's Liberation Army, the Khartoum government, or bandit groups that take advantage of the chaos, have attacked civilians. In view of this, regional agencies should show more seriousness in finding solutions for the war, and perpetrators of rape should be brought to justice so as to change the perception of rape as an unfortunate but inevitable side effect of war.

  19. Epidemiology of dengue infections in Kassala, Eastern Sudan.

    PubMed

    Abdallah, Tajeldin M; Ali, Abdel Aziem A; Karsany, Mubarak S; Adam, Ishag

    2012-03-01

    Eighty-one (71.7%) out of 113 patients had confirmed dengue infection (using ELISA IgM serology) at Kassala, Eastern Sudan during the period of August through November 2010. According to the WHO criteria, dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) were observed in 30.9, 58, and 11.1% of these patients, respectively. The mean age of these 81 patients was 25.5 years. Male:female ratio was 1.8:1. Various symptoms including fever (100%), headache (75.3%), vomiting (55.6%), nausea (53.1%), and backache (30.9%) were observed among these patients. Thrombocytopenia (<100/10(9) platelets/L), and leucopenia (WBC count <4,000 × 10(9) cells/L) and hemoconcentration (hematocrit >45) were reported in 86.4, 69.1, and 67.9% of the patients, respectively. High alanine aminotransferase (ALT, >65 U/L) and aspartate aminotransferase (AST >37 U/L) were seen in 9.9 and 14.8% of the patients, respectively. There were five (6.1%) deaths, three of them had DHF and the other two patients had DSS.

  20. Correlation of measles and dengue infection in Kassala, Eastern Sudan.

    PubMed

    Abdalla, Tajeldin M; Karsany, Mubarak S; Ali, AbdelAziem A

    2015-01-01

    Using the clinical case definition adopted by the World Health Organization, a total of 275 suspected cases of measles were enrolled in this study during January-March 2012 in Kassala Teaching Hospital, Eastern Sudan. Various clinical manifestations (fever, headache, cough, coryza, conjunctivitis, skin rash, vomiting, diarrhoea, convulsion, and hemorrhagic manifestations) were reported among these patients. Blood was withdrawn from the first 64 (23.3%) patients. Two samples were hemolyzed and only 60 samples (21.8%) were investigated for measles and dengue IgM antibodies. Antibodies for measles, dengue, and co-infection were detected in the plasma of 12 (20%), seven (11.7%), and 10 (16.7%) samples, respectively. Although there was no significant difference in age, residence, occupation, and vaccination status among the different groups, a high proportion of male patients (P = 0.011), severe cases (P = 0.004), and death ((P = 0.001) were reported among co-infected cases.

  1. Electrochemical determination of Sudan I in food products using a carbon nanotube-ionic liquid composite modified electrode.

    PubMed

    Liu, Benzhi; Yin, Chuntao; Wang, Min

    2014-01-01

    A sensitive and convenient electrochemical method was developed for the determination of Sudan I using a carbon nanotube-ionic liquid composite modified electrode with the enhancement effect of cetyltrimethyl ammonium bromide (CTAB). The modified electrode exhibited an obvious electrocatalytic activity towards the oxidation of Sudan I, and the oxidation peak current significantly increased in the presence of CTAB. The experimental parameters, such as solution pH, concentration of CTAB and accumulation time, were optimised for Sudan I determination. The oxidation peak current showed a linear relationship with the concentration of Sudan I in the range of 3.0 × 10(-8) to 3.1 × 10(-6) mol l(-1), with a detection limit of 8.0 × 10(-9) mol l(-1). The proposed method was successfully applied for the determination of Sudan I in food products of ketchup and chilli sauce. PMID:25254422

  2. Molecular identification of different Theileria and Babesia species infecting sheep in Sudan.

    PubMed

    El Imam, Ahmed H; Hassan, Shawgi M; Gameel, Ahmed A; El Hussein, Abdelrahim M; Taha, Khalid M; Oosthuizen, Marinda C

    2016-01-01

    The epidemiological aspects of sheep piroplasmosis in Sudan are poorly studied, and further investigations using sensitive and precise techniques are required. In this study, the Reverse Line Blot (RLB) hybridization assay was used to detect and simultaneously differentiate between Theileria and Babesia species. DNA was extracted from blood collected on filter paper (n=219) from apparently healthy sheep from six different geographical localities in Sudan. Results indicated that Theileria ovis (88.6%), T. separata (20.1%), T. lestoquardi (16.4%) and T. annulata (16.4%) DNA could be detected in the blood samples. Single and mixed Theileria infections were detected in 74 (33.8%) and 124 (56.6%) respectively and T. ovis being the most prevalent species in the country. T. ovis and T. separata were reported for the first time in sheep in Sudan. PMID:27262957

  3. A new genus for a rare African vespertilionid bat: insights from South Sudan

    PubMed Central

    Reeder, DeeAnn M.; Helgen, Kristofer M.; Vodzak, Megan E.; Lunde, Darrin P.; Ejotre, Imran

    2013-01-01

    Abstract A new genus is proposed for the strikingly patterned African vespertilionid “Glauconycteris” superba Hayman, 1939 on the basis of cranial and external morphological comparisons. A review of the attributes of a newly collected specimen from South Sudan (a new country record) and other museum specimens of “Glauconycteris” superba suggests that “Glauconycteris” superba is markedly distinct ecomorphologically from other species classified in Glauconycteris and is likely the sister taxon to Glauconycteris sensu stricto. The recent capture of this rarely collected but widespread bat highlights the need for continued research in tropical sub-Saharan Africa and in particular, for more work in western South Sudan, which has received very little scientific attention. New country records for Glauconycteris cf. poensis (South Sudan) and Glauconycteris curryae (Gabon) are also reported. PMID:23805046

  4. [Rapid determination of Sudan dyes adulterated in natural paprika red by FTIR].

    PubMed

    Zhang, Wei-wei; Liu, Ling-ling; Wu, Yan-wen; Ouyang, Jie; Sun, Su-qin

    2012-04-01

    How to rapidly determine synthesized pigments or dyes adulterated in natural pigments is a difficult problem for food analysts. Natural paprika red is widely used in foods because of its coloration and pharmaceutical effect, but it is sometimes adulterated with Sudan dyes for its poor stability under light or heat treatment. In the present paper, the macro-fingerprint characteristic of infrared spectroscopy was utilized to identify Sudan dyes adulterated in paprika red. The strong peaks at 1 621, 1 500 and 751 cm(-1) in FTIR spectra and at the fingerprint region of 753, 684 and 496 cm(-1) in the secondary deriative FTIR spectra were remarkable characteristics for Sudan dyes adulterated in paprika red, of which the limit of determination was about 1%.

  5. Molecular identification of different Theileria and Babesia species infecting sheep in Sudan.

    PubMed

    El Imam, Ahmed H; Hassan, Shawgi M; Gameel, Ahmed A; El Hussein, Abdelrahim M; Taha, Khalid M; Oosthuizen, Marinda C

    2016-01-01

    The epidemiological aspects of sheep piroplasmosis in Sudan are poorly studied, and further investigations using sensitive and precise techniques are required. In this study, the Reverse Line Blot (RLB) hybridization assay was used to detect and simultaneously differentiate between Theileria and Babesia species. DNA was extracted from blood collected on filter paper (n=219) from apparently healthy sheep from six different geographical localities in Sudan. Results indicated that Theileria ovis (88.6%), T. separata (20.1%), T. lestoquardi (16.4%) and T. annulata (16.4%) DNA could be detected in the blood samples. Single and mixed Theileria infections were detected in 74 (33.8%) and 124 (56.6%) respectively and T. ovis being the most prevalent species in the country. T. ovis and T. separata were reported for the first time in sheep in Sudan.

  6. Direct method for determination of Sudan I in FD&C Yellow No. 6 and D&C Orange No. 4 by reversed-phase liquid chromatography.

    PubMed

    Petigara, Bhakti R; Scher, Alan L

    2007-01-01

    A reversed-phase liquid chromatographic method was developed to determine parts-per-million and higher levels of Sudan 1, 1-(phenylazo)-2-naphthalenol, in the disulfo monoazo color additive FD&C Yellow No. 6 and in a related monosulfo monoazo color additive, D&C Orange No. 4. Sudan I, the corresponding unsulfonated monoazo dye, is a known impurity in these color additives. The color additives are dissolved in water and methanol, and the filtered solutions are directly chromatographed, without extraction or concentration, by using gradient elution at 0.25 mL/min. Calibrations from peak areas at 485 nm were linear. At a 99% confidence level, the limits of determination were 0.008 microg Sudan I/mL (0.4 ppm) in FD&C Yellow No. 6 and 0.011 microg Sudan I/mL (0.00011%) in D&C Orange No. 4. The confidence intervals were 0.202 +/- 0.002 microg Sudan I/mL (10.1 +/- 0.1 ppm) near the specification level for Sudan I in FD&C Yellow No. 6 and 20.0 +/- 0.2 microg Sudan I/mL (0.200 +/- 0.002%) near the highest concentration of Sudan I found in D&C Orange No. 4. A survey was conducted to determine Sudan I in 28 samples of FD&C Yellow No. 6 from 17 international manufacturers over 3 years, and in a pharmacology-tested sample. These samples were found to contain undetected levels (16 samples), 0.5-9.7 ppm Sudan I (0.01-0.194 microg Sudan I/mL in analyzed solutions; 11 samples including the pharmacology sample), and > or =10 ppm Sudan I (> or = 0.2 microg Sudan I/mL; 2 samples). Analyses of 21 samples of D&C Orange No. 4 from 8 international manufacturers over 4 years found Sudan I at undetected levels (8 samples), 0.0005 to < 0.005% Sudan I (0.05 to < 0.5 microg Sudan I/mL in analyzed solutions; 3 samples, including a pharmacology batch), 0.005 to <0.05% Sudan I (0.5 to <5 microg Sudan I/mL; 9 samples), and 0.18% Sudan I (18 microg Sudan I/mL; 1 sample).

  7. Characterization of epidemic and nonepidemic Neisseria meningitidis serogroup A strains from Sudan and Sweden.

    PubMed Central

    Salih, M A; Danielsson, D; Bäckman, A; Caugant, D A; Achtman, M; Olcén, P

    1990-01-01

    A random selection of 25 strains isolated during an epidemic caused by serogroup A Neisseria meningitidis in Sudan (1988), 3 preepidemic meningococcal strains (1985), and 26 serogroup A strains isolated from sporadic cases of meningitis in Sweden (1973 to 1987) were assessed for multilocus enzyme genotypes (ETs), DNA restriction enzyme patterns, outer membrane proteins, lipopolysaccharides, pilus formation, and antibiograms. All of the 25 Sudanese epidemic isolates and 22 of the Swedish strains were of the same or closely related ETs (ETs 3, 4, and 5), corresponding to clone III-1, which has been responsible for two pandemic waves in the last three decades. The earlier pandemic involved Scandinavia, and the last one caused an outbreak during the pilgrimage to Mecca, Saudi Arabia (August 1987), spreading to Sudan, Chad, and Ethiopia. The three Sudanese preepidemic isolates (1985) were clone IV-1 (sulfonamide susceptible), which has been resident in the African meningitis belt for the last 25 years. The uniformity of clone III-1 strains (all sulfonamide resistant) from Sudan and Sweden was confirmed by DNA restriction enzyme patterns. ETs 3, 4, and 5 from Sudan and Sweden had 86 to 100% similarity to a Swedish clone III-1 reference strain, whereas ETs 1, 2, 6, and 7 showed 50 to 80% similarity. Class 1 protein for clone III-1 showed serosubtype antigens P1.9 and P1.x, whereas ET6 strains (clone IV-1) had serosubtype P1.7. Lipopolysaccharides were variable in the Sudanese and Swedish strains. Pili were expressed in all clone III-1 isolates from Sudan and Sweden but in none of the clone IV-1 isolates (Sudan, 1985). Images PMID:1975593

  8. Towards global Guinea worm eradication in 2015: the experience of South Sudan.

    PubMed

    Awofeso, Niyi

    2013-08-01

    For centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies.

  9. Towards global Guinea worm eradication in 2015: the experience of South Sudan.

    PubMed

    Awofeso, Niyi

    2013-08-01

    For centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies. PMID:23623648

  10. Genetic diversity and population structure of Plasmodium vivax isolates from Sudan, Madagascar, French Guiana and Armenia.

    PubMed

    Menegon, Michela; Durand, Patrick; Menard, Didier; Legrand, Eric; Picot, Stéphane; Nour, Bakri; Davidyants, Vladimir; Santi, Flavia; Severini, Carlo

    2014-10-01

    Polymorphic genetic markers and especially microsatellite analysis can be used to investigate multiple aspects of the biology of Plasmodium species. In the current study, we characterized 7 polymorphic microsatellites in a total of 281 Plasmodium vivax isolates to determine the genetic diversity and population structure of P. vivax populations from Sudan, Madagascar, French Guiana, and Armenia. All four parasite populations were highly polymorphic with 3-32 alleles per locus. Mean genetic diversity values was 0.83, 0.79, 0.78 and 0.67 for Madagascar, French Guiana, Sudan, and Armenia, respectively. Significant genetic differentiation between all four populations was observed.

  11. Seasonal variation of carbon fluxes in a sparse savanna in semi arid Sudan

    PubMed Central

    Ardö, Jonas; Mölder, Meelis; El-Tahir, Bashir Awad; Elkhidir, Hatim Abdalla Mohammed

    2008-01-01

    both during the dry and wet season 2005. The small sink during the dry season is surprising and similar dry season sinks have not to our knowledge been reported from other similar savanna ecosystems and could have potential management implications for agroforestry. A strong response of NEE versus small changes in plant available soil water content was found. Collection and analysis of flux data for several consecutive years including variations in precipitation, available soil moisture and labile soil carbon are needed for understanding the year to year variation of the carbon budget of this grass land/sparse savanna site in semi arid Sudan. PMID:19046418

  12. Late Quaternary vegetation, biodiversity and fire dynamics on the southern Brazilian highland and their implication for conservation and management of modern Araucaria forest and grassland ecosystems.

    PubMed

    Behling, Hermann; Pillar, Valério DePatta

    2007-02-28

    Palaeoecological background information is needed for management and conservation of the highly diverse mosaic of Araucaria forest and Campos (grassland) in southern Brazil. Questions on the origin of Araucaria forest and grasslands; its development, dynamic and stability; its response to environmental change such as climate; and the role of human impact are essential. Further questions on its natural stage of vegetation or its alteration by pre- and post-Columbian anthropogenic activity are also important. To answer these questions, palaeoecological and palaeoenvironmental data based on pollen, charcoal and multivariate data analysis of radiocarbon dated sedimentary archives from southern Brazil are used to provide an insight into past vegetation changes, which allows us to improve our understanding of the modern vegetation and to develop conservation and management strategies for the strongly affected ecosystems in southern Brazil.

  13. Oral health of visually impaired schoolchildren in Khartoum State, Sudan

    PubMed Central

    2013-01-01

    Background Although oral health care is a vital component of overall health, it remains one of the greatest unattended needs among the disabled. The aim of this study was to assess the oral health status and oral health-related quality of life (Child-OIDP in 11-13-year-old) of the visually challenged school attendants in Khartoum State, the Sudan. Methods A school-based survey was conducted in Al-Nour institute [boys (66.3%), boarders (35.9%), and children with partial visual impairment (PVI) (44.6%)]. Two calibrated dentists examined the participants (n=79) using DMFT/dmft, Simplified Oral Hygiene Index (OHI-S), dental care index, and traumatic dental injuries (TDI) index. Oral health related quality of life (C-OIDP) was administered to 82 schoolchildren. Results Caries experience was 46.8%. Mean DMFT (age≥12, n=33) was 0.4 ± 0.7 (SiC 1.6), mean dmft (age<12, n=46) was 1.9 ±2.8 (SiC 3.4), mean OHIS 1.3 ± 0.9. Care Index was zero. One fifth of the children suffered TDI (19%). Almost one third (29%) of the 11–13 year old children reported an oral impact on their daily performances. A quarter of the schoolchildren (25.3%) required an urgent treatment need. Analysis showed that children with partial visual impairment (PVI) were 6.3 times (adjusted) more likely to be diagnosed with caries compared to children with complete visual impairment (CVI), and children with caries experience were 1.3 times (unadjusted) more likely to report an oral health related impact on quality of life. Conclusions Visually impaired schoolchildren are burdened with oral health problems, especially caries. Furthermore, the 11-13 year olds' burden with caries showed a significant impact on their quality of life. PMID:23866155

  14. Neonatal respiratory distress in Omdurman Maternity Hospital, Sudan

    PubMed Central

    Hamed, Selma MA; Nasr, Abdelhaleem

    2014-01-01

    Neonatal respiratory distress (NRD) is a common neonatal problem, which is responsible for high morbidity and mortality. There are few published studies in developing countries addressing neonatal respiratory distress. There is no previously published study in Sudan on this problem. The objective of the study is to determine the frequency, different causes, immediate outcome. It was a prospective, descriptive, cross sectional hospital-based study which was carried out in neonatal intensive care unit (NICU) of Omdurman Maternity Hospital, between February-March 2013. The study enrolled all Sudanese newborns from 0-28 days including normal, low and high birth weight of different gestational ages admitted to the neonatal intensive care unit and diagnosed as neonatal respiratory distress. The frequency of NRD was calculated, the causes and immediate outcome were determined. Results showed that the frequency rate of NRD was (4.83%) among the total number of hospital (2071) live births during the period of the study. The commonest causes were transient tachypnoea of the newborn (TTN) in 28% of cases, sepsis in 24% of cases and hyaline membrane disease (HMD) in 15% of cases. The outcome of NRD was: cure in 56% of cases, death in 36% of cases, and patients discharged with complications in 8% of cases. In conclusion, the study confirmed the importance of NRD with a frequency rate of 4.83%, morbidity of 8% and mortality of 36% of cases. The causes and immediate outcome were determined and discussed. Some recommendations were suggested in order to reduce its frequency, morbidity and mortality. PMID:27493392

  15. The Holocene Geoarchaeology of the Desert Nile in Northern Sudan

    NASA Astrophysics Data System (ADS)

    Woodward, Jamie; Macklin, Mark; Spencer, Neal; Welsby, Derek; Dalton, Matthew; Hay, Sophie; Hardy, Andrew

    2016-04-01

    Invited Paper Forty years ago Colin Renfrew declared that "every archaeological problem starts as a problem in geoarchaeology" (Renfrew, 1976 p. 2). With this assertion in mind, this paper draws upon the findings from field research in two sectors of the Nile Valley of Northern Sudan dedicated to the exploration of human-environment interactions during the middle and late Holocene. This part of the Nile corridor contains a rich cultural record and an exceptionally well preserved Holocene fluvial archive. A distinctive feature of these records is the variety of evidence for interaction between desert and river over a range of spatial and temporal scales. This interaction presented both challenges and opportunities for its ancient inhabitants. This paper will present evidence for large-scale landscape changes driven by shifts in global climate. It will also show how we have integrated the archaeological and geological records in the Northern Dongola Reach and at Amara West - where long-term field projects led by archaeologists from the British Museum have recognised the importance of a sustained commitment to interdisciplinary research to achieve a fully integrated geoarchaeological approach across a range of scales. The former project is a large-scale landscape survey with multiple sites across an 80 km reach of the Nile whilst the latter has a strong focus on a single New Kingdom town site and changes in its environmental setting. By combining multiple archaeological and geological datasets - and pioneering the use of OSL dating and strontium isotope analysis in the Desert Nile - we have developed a new understanding of human responses to Holocene climate and landscape change in this region. Renfrew, C. (1976) Archaeology and the earth sciences. In: D.A. Davidson and M.I. Shackley (eds) Geoarchaeology: Earth Science and the Past, Duckworth, London, 1-5.

  16. A New Model for Management of Mycetoma in the Sudan

    PubMed Central

    Fahal, Ahmed; Mahgoub, El Sheikh; EL Hassan, Ahmed Mohamed; Abdel-Rahman, Manar Elsheikh; Alshambaty, Yassir; Hashim, Ahmed; Hago, Ali; Zijlstra, Eduard E.

    2014-01-01

    Patients with mycetoma usually present late with advanced disease, which is attributed to lack of medical and health facilities in endemic areas, poor health education and low socio-economic status. With this background, an integrated patient management model at the village level was designed to address the various problems associated with mycetoma. The model was launched in an endemic village in the Sudan, between 2010 and 2013. This model is described in a prospective, descriptive, community-based study, aimed to collect epidemiological, ecological, and clinical data and to assess knowledge, attitude and practice (KAP) in order to design effective and efficient management measures. In this study, the prevalence of mycetoma was 14.5 per 1,000 inhabitants. The patients were farmers, housewives and children of low socio-economic status, and no obvious risk group was detected. All had surgery performed in a mobile surgical unit in the village which encouraged patients to present early with small early lesion leading to a good clinical outcome. The close contact with the Acacia tree thorns, animals and animal dung, walking bare footed and practising poor hygiene may all have contributed to the development of mycetoma in the village. Knowledge of mycetoma was poor in 96.3% of the study population, 70% had appropriate attitudes and beliefs towards interaction with mycetoma patients and treatment methods, and 49% used satisfactory or good practices in the management of mycetoma. Knowledge and practices on mycetoma were found to be significantly associated with age. Based on the KAP and epidemiological data, several health education sessions were conducted in the village for different target groups. The integrated management approach adopted in this study is unique and appeared successful and seems suitable as an immediate intervention. While for the longer term, establishment of local health facilities with trained health staff remains a priority. PMID:25356640

  17. Petrology of Nile River sands (Ethiopia and Sudan): Sediment budgets and erosion patterns

    NASA Astrophysics Data System (ADS)

    Garzanti, Eduardo; Andò, Sergio; Vezzoli, Giovanni; Ali Abdel Megid, Ada; El Kammar, Ahmed

    2006-12-01

    Detrital modes of modern Nile sands, together with estimates of sediment volumes trapped in Sudanese reservoirs, allow us to calculate sediment loads of major tributaries (Blue Nile, White Nile, Atbara) and erosion rates in the Nile catchment. A tridimensional array of high-resolution bulk-petrography and heavy-mineral data was obtained on both levee (suspended load) and bar (bedload) deposits, analysed separately for each grain-size subclass at 0.5 Φ intervals. From available information on sediments stored in the Roseires, Khashm el Girba and Lake Nasser reservoirs between 1964 and 1990, the total Nile load is reassessed at 230 ± 20 10 6 t/a, an estimate two to four times higher than figures reported so far, on which previous estimates of sediment yields and erosion rates were based. Of such huge amount of detritus, 82 ± 10 10 6 t/a are contributed by River Atbara, which carries more volcanic rock fragments, brown augite and olivine from basaltic rocks, and 140 ± 20 10 6 t/a by the Blue Nile, which carries more K-feldspar and hornblende from amphibolite-facies basement rocks. The additional ≤ 10 7 t/a of almost purely quartzose sediments supplied by the rest of the Nile catchment, corresponding to insignificant average yields and erosion rates, represent the stable residue which survived extreme subequatorial weathering in southern Sudan swamps (White Nile, Bahr ez Zeraf, and Sobat sands) or fluvial and eolian recycling of ancient quartzarenites in hyperarid climates (Nubian sands). Sediment production is thus markedly focused on Ethiopian rift highlands, where rainfall is concentrated in a single July-August peak. High average yields and erosion rates (800 ± 150 t/km 2 a, 0.29 ± 0.05 mm/a) partly reflect anthropically-accelerated erosion caused by deforestation and intensive land use, and cannot be extrapolated far in the past. Erosion patterns may have changed repeatedly during Quaternary climatic oscillations, and possibly also in the longer term

  18. Gender differences in the prevalence and determinants of tobacco use among school-aged adolescents (11 – 17 years) in Sudan and South Sudan

    PubMed Central

    Atari, Dominic Odwa

    2014-01-01

    Introduction Tobacco use is one of the leading and preventable causes of global morbidities and premature mortalities. The study explores gender differences in the prevalence and determinants of tobacco use among school-aged adolescents (11-17years) in Sudan and South Sudan. Methods The study utilized the national Global Youth Tobacco Survey (GYTS) data collected in 2005 for Sudan (4,277 unweighted; 131,631 weighted). Univariate and bivariate analyses were conducted to examine the associations between the dependent (tobacco use status) and independent variables. Logistic regression analyses were performed to identify the key factors which influence tobacco consumption among adolescents in the 2 Sudans for ever cigarette users, current cigarette users, and users of noncigarette tobacco products. Results There were significant gender differences in the prevalence of ever cigarette users (21.8%; male=13.1%, female=6.5%, p<0.05) and current cigarette users (6.9%; male=4.9%, female = 1.3%, p<0.05) but not among users of noncigarette tobacco products (14.7%; male=6.8%, female=6.1%). Adolescent tobacco use was significantly associated with availability of monthly income or allowance, exposure to tobacco industry promotions, and tobacco-use behavior of familial relations. Knowledge about the harmful effects of secondhand smoke was related with decreased likelihood of tobacco use. Conclusion School programs that focus on health messages alone may not work for the adolescent population. Legislations that ban all types of tobacco advertisements, promotions, and sponsorships among adolescents are needed in the 2 countries. PMID:25404978

  19. Association of tomato leaf curl Sudan virus with leaf curl disease of tomato in Jeddah, Saudi Arabia.

    PubMed

    Sohrab, Sayed Sartaj; Yasir, Muhammad; El-Kafrawy, Sherif Ali; Abbas, Ayman T; Mousa, Magdi Ali Ahmed; Bakhashwain, Ahmed A

    2016-06-01

    Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed.

  20. Association of tomato leaf curl Sudan virus with leaf curl disease of tomato in Jeddah, Saudi Arabia.

    PubMed

    Sohrab, Sayed Sartaj; Yasir, Muhammad; El-Kafrawy, Sherif Ali; Abbas, Ayman T; Mousa, Magdi Ali Ahmed; Bakhashwain, Ahmed A

    2016-06-01

    Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed. PMID:27366765

  1. Cenozoic tectonic and climatic events in southern Iberian Peninsula: Implications for the evolutionary history of freshwater fish of the genus Squalius (Actinopterygii, Cyprinidae).

    PubMed

    Perea, Silvia; Cobo-Simon, Marta; Doadrio, Ignacio

    2016-04-01

    Southern Iberian freshwater ecosystems located at the border between the European and African plates represent a tectonically complex region spanning several geological ages, from the uplifting of the Betic Mountains in the Serravalian-Tortonian periods to the present. This area has also been subjected to the influence of changing climate conditions since the Middle-Upper Pliocene when seasonal weather patterns were established. Consequently, the ichthyofauna of southern Iberia is an interesting model system for analyzing the influence of Cenozoic tectonic and climatic events on its evolutionary history. The cyprinids Squalius malacitanus and Squalius pyrenaicus are allopatrically distributed in southern Iberia and their evolutionary history may have been defined by Cenozoic tectonic and climatic events. We analyzed MT-CYB (510 specimens) and RAG1 (140 specimens) genes of both species to reconstruct phylogenetic relationships and to estimate divergence times and ancestral distribution ranges of the species and their populations. We also assessed their levels of genetic structure and diversity as well as the amount of gene flow between populations. To investigate recent paleogeographical and climatic factors in southern Iberia, we modeled changes-through-time in sea level from the LGM to the present. Phylogenetic, geographic and population structure analyses revealed two well-supported species (S. malacitanus and S. pyrenaicus) in southern Iberia and two subclades (Atlantic and Mediterranean) within S. malacitanus. The origin of S. malacitanus and the separation of its Atlantic and Mediterranean populations occurred during the Serravalian-Tortonian and Miocene-Pliocene periods, respectively. These divergence events occurred in the Middle Pliocene and Pleistocene in S. pyrenaicus. In both species, Atlantic basins possessed populations with higher genetic diversity than Mediterranean, which may be explained by the Janda Lagoon. The isolation of S. malacitanus was

  2. Cenozoic tectonic and climatic events in southern Iberian Peninsula: Implications for the evolutionary history of freshwater fish of the genus Squalius (Actinopterygii, Cyprinidae).

    PubMed

    Perea, Silvia; Cobo-Simon, Marta; Doadrio, Ignacio

    2016-04-01

    Southern Iberian freshwater ecosystems located at the border between the European and African plates represent a tectonically complex region spanning several geological ages, from the uplifting of the Betic Mountains in the Serravalian-Tortonian periods to the present. This area has also been subjected to the influence of changing climate conditions since the Middle-Upper Pliocene when seasonal weather patterns were established. Consequently, the ichthyofauna of southern Iberia is an interesting model system for analyzing the influence of Cenozoic tectonic and climatic events on its evolutionary history. The cyprinids Squalius malacitanus and Squalius pyrenaicus are allopatrically distributed in southern Iberia and their evolutionary history may have been defined by Cenozoic tectonic and climatic events. We analyzed MT-CYB (510 specimens) and RAG1 (140 specimens) genes of both species to reconstruct phylogenetic relationships and to estimate divergence times and ancestral distribution ranges of the species and their populations. We also assessed their levels of genetic structure and diversity as well as the amount of gene flow between populations. To investigate recent paleogeographical and climatic factors in southern Iberia, we modeled changes-through-time in sea level from the LGM to the present. Phylogenetic, geographic and population structure analyses revealed two well-supported species (S. malacitanus and S. pyrenaicus) in southern Iberia and two subclades (Atlantic and Mediterranean) within S. malacitanus. The origin of S. malacitanus and the separation of its Atlantic and Mediterranean populations occurred during the Serravalian-Tortonian and Miocene-Pliocene periods, respectively. These divergence events occurred in the Middle Pliocene and Pleistocene in S. pyrenaicus. In both species, Atlantic basins possessed populations with higher genetic diversity than Mediterranean, which may be explained by the Janda Lagoon. The isolation of S. malacitanus was

  3. Hydrocarbon potential evaluation of the source rocks from the Abu Gabra Formation in the Sufyan Sag, Muglad Basin, Sudan

    NASA Astrophysics Data System (ADS)

    Qiao, Jinqi; Liu, Luofu; An, Fuli; Xiao, Fei; Wang, Ying; Wu, Kangjun; Zhao, Yuanyuan

    2016-06-01

    The Sufyan Sag is one of the low-exploration areas in the Muglad Basin (Sudan), and hydrocarbon potential evaluation of source rocks is the basis for its further exploration. The Abu Gabra Formation consisting of three members (AG3, AG2 and AG1 from bottom to top) was thought to be the main source rock formation, but detailed studies on its petroleum geology and geochemical characteristics are still insufficient. Through systematic analysis on distribution, organic matter abundance, organic matter type, organic matter maturity and characteristics of hydrocarbon generation and expulsion of the source rocks from the Abu Gabra Formation, the main source rock members were determined and the petroleum resource extent was estimated in the study area. The results show that dark mudstones are the thickest in the AG2 member while the thinnest in the AG1 member, and the thickness of the AG3 dark mudstone is not small either. The AG3 member have developed good-excellent source rock mainly with Type I kerogen. In the Southern Sub-sag, the AG3 source rock began to generate hydrocarbons in the middle period of Bentiu. In the early period of Darfur, it reached the hydrocarbon generation and expulsion peak. It is in late mature stage currently. The AG2 member developed good-excellent source rock mainly with Types II1 and I kerogen, and has lower organic matter abundance than the AG3 member. In the Southern Sub-sag, the AG2 source rock began to generate hydrocarbons in the late period of Bentiu. In the late period of Darfur, it reached the peak of hydrocarbon generation and its expulsion. It is in middle mature stage currently. The AG1 member developed fair-good source rock mainly with Types II and III kerogen. Throughout the geological evolution history, the AG1 source rock has no effective hydrocarbon generation or expulsion processes. Combined with basin modeling results, we have concluded that the AG3 and AG2 members are the main source rock layers and the Southern Sub-sag is

  4. Research On: Motivation to Learn English among College Students in Sudan

    ERIC Educational Resources Information Center

    Humaida, Ibrahim Abdelrahim Ibrahim

    2012-01-01

    This research was conducted to achieve the following objectives: to examine motivation to learn English language among students of faculty of arts, Islamic University-Sudan, to find out if there were significant statistical differences on motivation scores related to both student level and age. To pursue these objectives, the researcher used the…

  5. Study of Characteristics, Attitudes and Opinions of the Students in the College of Agriculture in Sudan.

    ERIC Educational Resources Information Center

    Bannaga, Ali Mohayad

    In examining characteristics, attitudes, and opinions of the students in the College of Agriculture, University of Khartoum, in the Sudan, this study focused on eight independent variables: years in the College of Agriculture, location of permanent home, size of home town, length of hostel living experience, father's occupation, number of living…

  6. Risk Factors for Sustained Cholera Transmission, Juba County, South Sudan, 2014.

    PubMed

    Ujjiga, Thomas T A; Wamala, Joseph F; Mogga, Juma J H; Othwonh, Thabo O; Mutonga, David; Kone-Coulibaly, Asta; Shaikh, Masood Ali; Mpairwe, Allan M; Abdinasir, Abubaker; Abdi, Mohamed A; Yoti, Zabulon; Olushayo, Olu; Nyimol, Pinyi; Lul, Riek; Lako, Richard L; Rumunu, John

    2015-10-01

    We conducted a case-control study to identify risk factors for the 2014 cholera outbreak in Juba County, South Sudan. Illness was associated with traveling or eating away from home; treating drinking water and receiving oral cholera vaccination were protective. Oral cholera vaccination should be used to complement cholera prevention efforts.

  7. Reaching out and Partnering in the Sudan through Integrated Community-Oriented Teaching

    ERIC Educational Resources Information Center

    Abdelrahman, Samira; Al Fadil, Sumaia

    2011-01-01

    Community-university partnerships, if they are to be successful, must be firmly grounded in the context in which they take place. This paper describes the ways in which the University of Gezira in the Sudan from its very beginning was built on an understanding of rural communities. The university's Faculty of Medicine built its training around…

  8. 78 FR 1872 - Extension and Redesignation of Sudan for Temporary Protected Status

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-09

    ... been continuously residing in the United States since January 9, 2013, to obtain TPS, if eligible. The.... In addition to demonstrating continuous residence in the United States since January 9, 2013, initial... present in the United States since May 3, 2013, the effective date of the redesignation of Sudan,...

  9. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited transportation-related transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY...

  10. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited exportation and reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF...

  11. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY SUDANESE...

  12. South Sudan: Stakeholders' Views of Technical and Vocational Education and Training and a Framework for Action

    ERIC Educational Resources Information Center

    Atari, Dominic Odwa; McKague, Kevin

    2015-01-01

    The Republic of South Sudan, recently emerging from the longest civil war in contemporary African history, has set goals towards post-conflict reconstruction in many areas of social services. However, the educational infrastructure continues to struggle, and many stakeholders in government and international and local organisations are not…

  13. Situation Reports--Ceylon, Costa Rica, Ghana, Haiti, Morocco, Sudan, Tunisia, and U.S.A.

    ERIC Educational Resources Information Center

    International Planned Parenthood Federation, London (England).

    Data relating to population and family planning in eight countries are presented in these situation reports. Countries included are Ceylon, Costa Rica, Ghana, Haiti, Morocco, Sudan, Tunisia, and the United States of America. Information is provided under two topics, general background and family planning situation, where appropriate and if it is…

  14. Examining the Contemporary Status of an Education System: The Case of the Republic of South Sudan

    ERIC Educational Resources Information Center

    Banraba, Boboya James Edimond

    2015-01-01

    This paper attempts to examine the contemporary status of an education system. The paper takes the case of the Republic of South Sudan. The key issues the paper will examine are the education enrollment and completion rates while paying particular attention to inequalities in both access and quality among racial or ethnic groups, males and…

  15. E-Learning Sudan, Formal Learning for Out-of-School Children

    ERIC Educational Resources Information Center

    Stubbé, Hester; Badri, Aiman; Telford, Rebecca; van der Hulst, Anja; van Joolingen, Wouter

    2016-01-01

    E-Learning Sudan (ELS) is a custom-built computer/tablet game that provides alternative learning opportunities to Sudanese children who are excluded from education. Unique in ELS is that children can learn mathematics, in their own remote village, without a teacher. This research study assessed the effectiveness of ELS in two pilots through a…

  16. 3 CFR - Certification Concerning U.S. Participation in the United Nations Mission in South Sudan...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 3 The President 1 2013-01-01 2013-01-01 false Certification Concerning U.S. Participation in the United Nations Mission in South Sudan Consistent With Section 2005 of the American Servicemembers' Protection Act Presidential Documents Other Presidential Documents Memorandum of January 10, 2012 Certification Concerning U.S. Participation in...

  17. 3 CFR - Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 3 The President 1 2013-01-01 2013-01-01 false Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and Defense Services Under the Foreign Assistance Act of 1961, as Amended, and the Arms Export Control Act, as Amended Presidential Documents Other Presidential Documents Presidential Determination No. 2012-4...

  18. 78 FR 8360 - Addition of South Sudan to the Restricted Destinations List

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... (42 U.S.C. 5841); Solar, Wind, Waste, and Geothermal Power Act of 1990 sec. 5 (42 U.S.C. 2243... Standards. III. Environmental Impact: Categorical Exclusion. IV. Paperwork Reduction Act Statement. V... power program; however, South Sudan does have the need for radioactive sources for legitimate...

  19. Geologic assessment of the fossil energy and geothermal potential of the Sudan

    SciTech Connect

    Setlow, L.W.

    1983-01-01

    This preliminary report provides geological input to the consideration of appropriate activities that can enhance the exploration and development of fossil-fuel and possible geothermal energy resources of the Sudan, and is based on study of available literature in early 1982. 59 references, 16 figures, 7 tables.

  20. Feasibility of health systems strengthening in South Sudan: a qualitative study of international practitioner perspectives

    PubMed Central

    Jones, Abigail; Legido-Quigley, Helena

    2015-01-01

    Objective To explore the feasibility of health systems strengthening from the perspective of international healthcare implementers and donors in South Sudan. Design A qualitative interview study, with thematic analysis using the WHO health system building blocks framework. Setting South Sudan. Participants 17 health system practitioners, working for international agencies in South Sudan, were purposively sampled for their knowledge and experiences of health systems strengthening, services delivery, health policy and politics in South Sudan. Results Participants universally reported the health workforce as insufficient and of low capacity and service delivery as poor, while access to medicines was restricted by governmental lack of commitment in undertaking procurement and supply. However, progress was clear in improved county health department governance, health management information system functionality, increased health worker salary harmonisation and strengthened financial management. Conclusions Resurgent conflict and political tensions have negatively impacted all health system components and maintaining or continuing health system strengthening has become extremely challenging. A coordinated approach to balancing humanitarian need particularly in conflict-affected areas, with longer term development is required so as not to lose improvements gained. PMID:26700280

  1. A Basic Hybrid Library Support Model to Distance Learners in Sudan

    ERIC Educational Resources Information Center

    Abdelrahman, Omer Hassan

    2012-01-01

    Distance learning has flourished in Sudan during the last two decades; more and more higher education institutions offer distance learning programmes to off-campus students. Like on-campus students, distance learners should have access to appropriate library and information support services. They also have specific needs for library and…

  2. Civic Education and Peacebuilding: Examples from Iraq and Sudan. Special Report 254

    ERIC Educational Resources Information Center

    Levine, Daniel H.; Bishai, Linda S.

    2010-01-01

    Between 2006 and 2010, the United States Institute of Peace developed several civic education programs for Iraq and Sudan as part of broader efforts to promote postconflict stability and development and help prevent a return to violence. This report describes those programs after first examining the conceptual bases for civic education and how…

  3. Population-Level Effect of Cholera Vaccine on Displaced Populations, South Sudan, 2014

    PubMed Central

    Rumunu, John; Abubakar, Abdinasir; West, Haley; Ciglenecki, Iza; Helderman, Trina; Wamala, Joseph Francis; Vázquez, Olimpia de la Rosa; Perea, William; Sack, David A.; Legros, Dominique; Martin, Stephen; Lessler, Justin; Luquero, Francisco J.

    2016-01-01

    Following mass population displacements in South Sudan, preventive cholera vaccination campaigns were conducted in displaced persons camps before a 2014 cholera outbreak. We compare cholera transmission in vaccinated and unvaccinated areas and show vaccination likely halted transmission within vaccinated areas, illustrating the potential for oral cholera vaccine to stop cholera transmission in vulnerable populations. PMID:27192187

  4. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Prohibition on Conducting.... Restricted business operations means business operations in Sudan that include power production activities... the Department of the Treasury, or are expressly exempted under Federal law from the requirement to...

  5. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Prohibition on Conducting.... Restricted business operations means business operations in Sudan that include power production activities... the Department of the Treasury, or are expressly exempted under Federal law from the requirement to...

  6. The Naivasha Language Policy: The Language of Politics and the Politics of Language in the Sudan

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf Kamal; Makoni, Busi; Makoni, Sinfree Bullock

    2011-01-01

    This article provides a textual analysis of the Naivasha language provisions in Sudan in an attempt to explore how political discourse is manifested in each policy statement. Using Critical Discourse Analysis (CDA) as an analytic and interpretive framework, the article argues that the Naivasha language provisions as political discourse are shaped…

  7. The Sociolinguistics of Nationalism in the Sudan: The Politicisation of Arabic and the Arabicisation of Politics

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf; Makoni, Busi; Makoni, Sinfree; Mugaddam, Abdel Rahim

    2011-01-01

    This monograph describes the historiography of language ideologies that led to the politicisation of Arabic and the Arabicisation of politics in the Sudan, starting from British colonial rule until the Comprehensive Peace Agreement that was a precursor to the separation of the South as an independent state. The monograph shows that the…

  8. Southern Africa

    Atmospheric Science Data Center

    2013-04-16

    article title:  Southern Africa     View larger JPEG image ... visibility of smoke plumes and haze. The southern tip of South Africa is at the bottom of the image, and Zambia is at the top. ... MISR Team. Aug 25, 2000 - South Africa to Zambia including the Okavango Delta. project:  ...

  9. Genetic Diversity of the Outer Surface Protein C Gene of Southern Borrelia Isolates and Its Possible Epidemiological, Clinical, and Pathogenetic Implications

    PubMed Central

    Lin, Tao; Oliver, Jr., James H.; Gao, Lihui

    2002-01-01

    The ospC genes of 20 southern Borrelia strains were sequenced. The strains consisted of B. burgdorferi sensu stricto, B. andersonii, B. bissettii, one undescribed genospecies, MI-8, and one probably new Borrelia species, TXW-1. A high degree of similarity exists between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Lateral transfers of the ospC gene probably occurred between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Internal gene recombination appears to occur among them. The highest degree of genetic diversity among them was observed in the two variable domains (V1 and V2), semivariable domain (SV), and the species-specific epitopes (between amino acids 28 and 31). Differences in ospC sequences among southern strains reflect diversity at the strain and genospecies levels. MI-8, which was recognized as an undescribed genospecies in our previous reports, remains distinguishable in our current analysis of ospC genes and is distinct from B. burgdorferi sensu stricto. Interestingly, another undescribed southern isolate, TXW-1, was not amplified under various PCR conditions. Compared to European B. burgdorferi sensu stricto strains, American B. burgdorferi sensu stricto strains show greater genetic heterogeneity. Southern B. burgdorferi sensu stricto, B. andersonii, and B. bissettii isolates were intermixed with each other in the phylogenetic trees. In the derived trees in our work, at least one southeastern strain of B. burgdorferi, MI-2, most closely aligns with a so-called invasive cluster that possesses many proven human-invasive strains. Transmission experiments show that MI-2 and the strains in this group of southern spirochetes are able to infect mice and hamsters and that the typical vector of Lyme disease, Ixodes scapularis, can acquire the spirochetes from infected mammals. Currently, strain MI-2 appears to be the only southern isolate among the 20 we analyzed that

  10. A comparison of the physics of the northern and southern shelves of the eastern Bering Sea and some implications for the ecosystem

    NASA Astrophysics Data System (ADS)

    Stabeno, Phyllis J.; Farley, Edward V., Jr.; Kachel, Nancy B.; Moore, Sue; Mordy, Calvin W.; Napp, Jeffrey M.; Overland, James E.; Pinchuk, Alexei I.; Sigler, Michael F.

    2012-06-01

    Sufficient oceanographic measurements have been made in recent years to describe the latitudinal variation in the physics of the eastern Bering Sea shelf and the potential impact of climate change on the species assemblages in the two ecosystems (north and south). Many of the predicted ecosystem changes will result from alterations in the timing and extent of sea ice. It is predicted that the sea ice in the northern Bering Sea will be less common in May, but will continue to be extensive through April. In contrast, the southern shelf will have, on average, much less sea ice than currently observed, but with large interannual and multiyear variability until at least 2050. Thus, even under current climate warming scenarios, bottom temperatures on the northern shelf will remain cold. Based on biophysical measurements, the southern and northern ecosystems were divided by a North-South Transition at ˜60°N. The northern middle shelf was characterized by a freshwater lens at the surface, cold bottom temperatures, and a thicker pycnocline than found on the southern shelf. Subsurface phytoplankton blooms were common. In contrast, the southern shelf stratification was largely determined by temperature alone; the pycnocline was thin (often<3 m) and subsurface blooms were uncommon. Biological responses to climate warming could include greater north-south differences in zooplankton community structure, the transport of large Outer Shelf Domain crustacean zooplankton to the middle shelf, and the disappearance of two principal prey taxa (Calanus spp. and Thysanoessa spp.) of planktivorous fish, seabirds and whales. The response of commercially and ecologically important fish species is predicted to vary. Some species of fish (e.g., juvenile sockeye salmon, Oncorhynchus nerka) may expand their summer range into the northern Bering Sea; some (e.g., pink salmon, O. gorbuscha) may increase in abundance while still other species (e.g., walleye pollock and arrowtooth flounder

  11. Geochemistry, PbPb single zircon ages and NdSr isotope composition of Precambrian rocks from southern and eastern Ethiopia: implications for crustal evolution in East Africa

    NASA Astrophysics Data System (ADS)

    Teklay, M.; Kröner, A.; Mezger, K.; Oberhänsli, R.

    1998-02-01

    Geochemical and isotope data for granitoid rocks from southern and eastern Ethiopia delineate the presumed margin of the Pan-African juvenile terrain of the Arabian-Nubian Shield against an older crustal segment of unknown origin extending from eastern Ethiopia to northern Somalia. Granitoids from southern Ethiopia have higher Na 2O and {Na20 }/{K2O} and lower Cr and Ni than granitoids with comparable SiO 2 values from eastern Ethiopia. In southern Ethiopia three periods of magmatism are identified on the basis on single zircon {207Pb}/{206Pb} evaporation ages, namely at ˜850, ˜750-700 and ˜650-550 Ma, and these correlate well with events documented from other parts of Ethiopia and the Arabian-Nubian Shield. The initial ɛNd(700 Ma) and ɛsr(700 Ma) values range from -1.2 to +3.2 and from -13.4 to + 3.7, respectively, which precludes any significant contribution from much older continental crust in the generation of these rocks. Neodymium mean crustal residence ages, based on a depleted mantle model, range from 0.96 to 1.26 Ga. These data support the interpretation that southern Ethiopia constitutes part of the Arabian-Nubian Shield. In contrast, granitoids from eastern Ethiopia show geochemical features of S-type granites. In eastern Ethiopia Pal aeo-Neoproterozoic zircon ages (781-2489 Ma) are found. Initial ɛNd(700 Ma) and ɛsr(700 Ma) values range from-4.3 to -18.3 and + 33.3 to + 99.8, respectively. Neodymium mean crustal residence ages range from 1.62 to 2.88 Ga. These data, in comparison to the western and southern parts of Ethiopia, are indicative of considerable reworking of pre-Pan-African crust. Variations in age, SrNd isotope ratios and chemistry of the granitoids on a regional scale also suggest the existence of two separate basement terrains between southern and eastern Ethiopia, which may be separated by a tectonic line now concealed by Phanerozoic rocks. This tectonic line may represent a major tectonic boundary between the juvenile Arabian

  12. Women's income generation activities in Merowe Province, Northern State, Sudan.

    PubMed

    Pitamber, S; Osama, S

    1994-06-01

    Merowe province in rural northern Sudan has been divided into three local government council areas: Merowe, Karima, and Ed Debba. A government program was instituted to increase the welfare of residents and food production. A baseline survey of 490 respondents was conducted in order to ascertain how illiterate women viewed development in the area and to provide useful information for program design and implementation. Women from 24 villages were administered questionnaires, observed in their daily activities, and engaged in discussion in a local meeting place. Discussions were also held with members of the local Popular Committee. Demographic information was very sketchy about age, and 48% had no formal education in writing and reading. General reading and writing skills of the remainder were very poor. There were 500 female children and 502 male children, and the sex ratio varied among the 3 council areas. 52% were married and 14% were divorced or widowed and living with relatives. The average monthly income was from Ls. 700 to Ls. 3000 based on reports from only 59.3% of respondents. Most of the women had skills in food processing and 25.7% were skilled in handicrafts. Water was obtained primarily from local wells and not decontaminated before use. Pit latrines were the standard. One bathing facility was available in the compound for the entire council area. Health units were either in each village or within 20-30 minutes walk. Child mortality was 4.3% in Merowe province. 77 children 0-5 years old died out of a total of 1002 live births. Life expectancy was 41-50 years for women and 61-70 years for men. Cleanliness and healthful eating were observed. 58% owned no land; plots were under 5 feddans and usually half a feddan. 92.1% had no bank account and 90% had no experience with loans. 70.2% were indifferent about involvement in an income generation program. 26% were interested in part-time participation. Only 3.9% desired full-time participation. 8.6% said they

  13. Magnetic Prospection at the Archaeological Site of Jebel Barkal, Sudan

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed A. Mohamed; Goldmann, Thomas; Wolf, Pawel; Wützler, Ronny; Goldmann, Lukas; Hobbs, Richard; Kendall, Timothy

    2010-05-01

    One of most important archaeological sites in northern Sudan is Jebel Barkal, an isolated sandstone butte, which became the chief cult center of the ancient Sudanese kingdom of Kush (ca. 800 BC-400 AD). Located on the western edge of the modern town of Karima, just downstream from the Nile's fourth cataract, Jebel Barkal is the site of numerous ruined palaces, temples, and pyramids. In 2006 and 2007, we carried out a magnetic survey of about 3.5 hectares of the temple area using an Overhauser magnetometer GSM 19. Our objective was to prospect some of the unexcavated areas of the site to try to image the sub-soil remains, and our resulting map clearly shows a number of magnetic anomalies of mud-brick, fired brick and stone-block walls belonging to different ancient buildings. Our initial magnetic results successfully revealed one corner of the wall of the early Meroitic palace B 100, which had been "lost" after its excavation in 1916, since it buried by later excavation debris before it had been precisely located on any site map. Prospection in the same area also revealed other (earlier?) massive mud walls of unknown function and character. A second area we chose for examination was that in front of the Great Amun Temple (B 500). Here we found two or three small rectangular anomalies that suggested a series of small chapels built at right angles to the paved way leading into the Great Temple; the layout was identical to chapels in front of the Great Amun Temple at Meroe. Another magnetic anomaly in front of B 500 seemed to be a predictable type of stepped podium, well-known from other Kushite temples. A third area we chose to examine was that northeast of B 500. Here we found the clear outline of a multi-chambered building (B 1700) parallel to the Great Temple, which appeared to have all the characteristics of a smaller temple fronted by a pylon. Far less clear were the complex magnetic anomalies we found northeast of B 1700. These appeared to belong to a series of

  14. Concomitant Infection with Leishmania donovani and L. major in Single Ulcers of Cutaneous Leishmaniasis Patients from Sudan.

    PubMed

    Babiker, A M; Ravagnan, S; Fusaro, A; Hassan, M M; Bakheit, S M; Mukhtar, M M; Cattoli, G; Capelli, G

    2014-01-01

    In Sudan human leishmaniasis occurs in different clinical forms, that is, visceral (VL), cutaneous (CL), mucocutaneous (ML), and post-kala-azar dermal leishmaniasis (PKDL). Clinical samples from 69 Sudanese patients with different clinical manifestations were subjected to a PCR targeting the cytochrome oxidase II (COII) gene for Leishmania species identification. Mixed infections were suspected due to multiple overlapping peaks presented in some sequences of the COII amplicons. Cloning these amplicons and alignment of sequences from randomly selected clones confirmed the presence of two different Leishmania species, L. donovani and L. major, in three out of five CL patients. Findings were further confirmed by cloning the ITS gene. Regarding other samples no significant genetic variations were found in patients with VL (62 patients), PKDL (one patient), or ML (one patient). The sequences clustered in a single homogeneous group within L. donovani genetic group, with the exception of one sequence clustering with L. infantum genetic group. Findings of this study open discussion on the synergetic/antagonistic interaction between divergent Leishmania species both in mammalian and vector hosts, their clinical implications with respect to parasite fitness and response to treatment, and the route of transmission with respect to vector distribution and or adaptation. PMID:24744788

  15. Antibody Treatment of Ebola and Sudan Virus Infection via a Uniquely Exposed Epitope within the Glycoprotein Receptor-Binding Site.

    PubMed

    Howell, Katie A; Qiu, Xiangguo; Brannan, Jennifer M; Bryan, Christopher; Davidson, Edgar; Holtsberg, Frederick W; Wec, Anna Z; Shulenin, Sergey; Biggins, Julia E; Douglas, Robin; Enterlein, Sven G; Turner, Hannah L; Pallesen, Jesper; Murin, Charles D; He, Shihua; Kroeker, Andrea; Vu, Hong; Herbert, Andrew S; Fusco, Marnie L; Nyakatura, Elisabeth K; Lai, Jonathan R; Keck, Zhen-Yong; Foung, Steven K H; Saphire, Erica Ollmann; Zeitlin, Larry; Ward, Andrew B; Chandran, Kartik; Doranz, Benjamin J; Kobinger, Gary P; Dye, John M; Aman, M Javad

    2016-05-17

    Previous efforts to identify cross-neutralizing antibodies to the receptor-binding site (RBS) of ebolavirus glycoproteins have been unsuccessful, largely because the RBS is occluded on the viral surface. We report a monoclonal antibody (FVM04) that targets a uniquely exposed epitope within the RBS; cross-neutralizes Ebola (EBOV), Sudan (SUDV), and, to a lesser extent, Bundibugyo viruses; and shows protection against EBOV and SUDV in mice and guinea pigs. The antibody cocktail ZMapp™ is remarkably effective against EBOV (Zaire) but does not cross-neutralize other ebolaviruses. By replacing one of the ZMapp™ components with FVM04, we retained the anti-EBOV efficacy while extending the breadth of protection to SUDV, thereby generating a cross-protective antibody cocktail. In addition, we report several mutations at the base of the ebolavirus glycoprotein that enhance the binding of FVM04 and other cross-reactive antibodies. These findings have important implications for pan-ebolavirus vaccine development and defining broadly protective antibody cocktails.

  16. Late Holocene Environmental Change at Amara West: A New Kingdom Town on the Desert Nile in Northern Sudan

    NASA Astrophysics Data System (ADS)

    Spencer, Neal; Woodward, Jamie; Macklin, Mark; Dalton, Matthew

    2014-05-01

    Amara West is a well-preserved town of the late New Kingdom downstream of Sai Island in Northern Sudan. The town has being identified as the seat of the pharaonic administration of Kush (Upper Nubia) in the Ramesside Period (c. 1306-1070 BC). This region fell under Egyptian control after about 1500 BC. The modern Nile (flowing eastwards in this reach) lies to the south of the town and a well preserved palaeochannel lies immediately to the north. Following the Egypt Exploration Society excavations of 1938-39 and 1947-48, it was argued that the ancient town was once located upon an island in the Nile. Renewed archaeological excavations allied to geomorphological work on the ancient river environment are attempting to establish the nature of the local and regional landscape before, during, and after the occupation of the town. This paper presents new OSL and radiocarbon dates on the sedimentary fill from the palaeochannel system to establish when the channel system ceased to flow on a permanent basis. Micromorphological work on the sedimentary records within the town provide additional insights into the nature of the local environment during the period of occupation. We discuss the implications of the new palaeoenvironmental data for our understanding of Amara West and we set out the wider significance of these new geoarchaeological data.

  17. Malaria control in South Sudan, 2006–2013: strategies, progress and challenges

    PubMed Central

    2013-01-01

    Background South Sudan has borne the brunt of years of chronic warfare and probably has the highest malaria burden in sub-Saharan Africa. However, effective malaria control in post-conflict settings is hampered by a multiplicity of challenges. This manuscript reports on the strategies, progress and challenges of malaria control in South Sudan and serves as an example epitome for programmes operating in similar environments and provides a window for leveraging resources. Case description To evaluate progress and challenges of the national malaria control programme an in-depth appraisal was undertaken according to the World Health Organization standard procedures for malaria programme performance review. Methodical analysis of published and unpublished documents on malaria control in South Sudan was conducted. To ensure completeness, findings of internal thematic desk assessments were triangulated in the field and updated by external review teams. Discussion and evaluation South Sudan has strived to make progress in implementing the WHO recommended malaria control interventions as set out in the 2006–2013 National Malaria Strategic Plan. The country has faced enormous programmatic constraints including infrastructure, human and financial resource and a weak health system compounded by an increasing number of refugees, returnees and internally displaced people. The findings present a platform on which to tailor an evidence-based 2014–2018 national malaria strategic plan for the country and a unique opportunity for providing a model for countries in a post-conflict situation. Conclusions The prospects for effective malaria control and elimination are huge in South Sudan. Nevertheless, strengthened coordination, infrastructure and human resource capacity, monitoring and evaluation are required. To achieve all this, allocation of adequate local funding would be critical. PMID:24160336

  18. Henry Solomon Wellcome: A philanthropist and a pioneer sponsor of medical research in the Sudan

    PubMed Central

    2013-01-01

    Henry Solomon Wellcome, the famous drug manufacturer had a fascinating association with the Sudan. Besides supporting tropical medicine research in this country, he established an extensive project in the Sudan that aimed at combining archeological excavations, philanthropy and social reform. This article is an archives-based account on this side of Wellcome’s association with the Sudan. The article starts with Wellcome’s early years in the American Midwest and the evolution of his career and his rise as a world-renowned drug manufacturer. After the battle of Omdurman, Wellcome visited Sudan in 1900 – 1901 where he offered to support the establishment of the research laboratories which later came to be known as the Wellcome Tropical Research Laboratories in Khartoum. He then became directly involved in the planning and running of extensive archeological excavations in the central Sudan. This project served as a field in which Wellcome found an outlet for his philanthropy. More than 4000 labourers were employed in Jebel Moya. Professional archeologists and anatomists were recruited by Wellcome to supervise the work, and all the requirements in terms of equipment were catered for. Wellcome devised a Savings Bank System whereby part of the earnings of each labourer were saved to him till the end of the season. He also introduced one of his innovations: aerial photography using box kite which was used for the first time in archeology. Wellcome made it a rule that no applicant should be turned away. The Camp Commandant had to find suitable work for each applicant, including the handicapped who were assigned to appropriate jobs like mending baskets or cutting grass for building huts. Wellcome’s welfare work had a significant impact on the local inhabitants of Jebel Moya. Henry Solomon Wellcome, 1906. Oil painting by Hugh Goldwin Riviere. Credit: Wellcome Library PMID:27493379

  19. Differential gene expression in Staphylococcus aureus exposed to Orange II and Sudan III azo dyes.

    PubMed

    Pan, Hongmiao; Xu, Joshua; Kweon, Oh-Gew; Zou, Wen; Feng, Jinhui; He, Gui-Xin; Cerniglia, Carl E; Chen, Huizhong

    2015-05-01

    We previously demonstrated the effects of azo dyes and their reduction metabolites on bacterial cell growth and cell viability. In this report, the effects of Orange II and Sudan III on gene expression profiling in Staphylococcus aureus ATCC BAA 1556 were analyzed using microarray and quantitative RT-PCR technology. Upon exposure to 6 μg/ml Orange II for 18 h, 21 genes were found to be differently expressed. Among them, 8 and 13 genes were up- and down-regulated, respectively. Most proteins encoded by these differentially expressed genes involve stress response caused by drug metabolism, oxidation, and alkaline shock indicating that S. aureus could adapt to Orange II exposure through a balance between up and down regulated gene expression. Whereas, after exposure to 6 μg/ml Sudan III for 18 h, 57 genes were differentially expressed. In which, 51 genes were up-regulated and 6 were down-regulated. Most proteins encoded by these differentially expressed genes involve in cell wall/membrane biogenesis and biosynthesis, nutrient uptake, transport and metabolite, and stress response, suggesting that Sudan III damages the bacterial cell wall or/and membrane due to binding of the dye. Further analysis indicated that all differentially expressed genes encoded membrane proteins were up-regulated and most of them serve as transporters. The result suggested that these genes might contribute to survival, persistence and growth in the presence of Sudan III. Only one gene msrA, which plays an important role in oxidative stress resistance, was found to be down-regulated after exposure to both Orange II and Sudan III. The present results suggested that both these two azo dyes can cause stress in S. aureus and the response of the bacterium to the stress is mainly related to characteristics of the azo dyes.

  20. Hepatitis C Virus Epidemiology in Djibouti, Somalia, Sudan, and Yemen: Systematic Review and Meta-Analysis

    PubMed Central

    Chaabna, Karima; Kouyoumjian, Silva P.; Abu-Raddad, Laith J.

    2016-01-01

    Objectives To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen. Methods Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five. Results We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%–1.9%), 1.0% (95%CI: 0.3%–1.9%) and 1.9% (95%CI: 1.4%–2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%–0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%–28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%–4.9%) in Somalia and 0.6% (95%CI: 0.4%–0.8%) in Sudan. Conclusion National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown. PMID:26900839

  1. Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution

    USGS Publications Warehouse

    Blakely, R.J.; Christiansen, R.L.; Guffanti, M.; Wells, R.E.; Donnelly-Nolan, J. M.; Muffler, L.J. Patrick; Clynne, M.A.; Smith, James G.

    1997-01-01

    Isostatic residual gravity anomalies in the southern Cascade Range of northern California and southern Oregon are spatially correlated with broad zones of Quaternary magmatism as reflected by the total volume of Quaternary volcanic products, the distribution of Quaternary vents, and the anomalously low teleseismic P wave velocities in the upper 30 km of crust. The orientation of Quaternary faults also appears to be related to gravity anomalies and volcanism in this area, trending generally north-south within the magmatic regions and northwest-southeast as they enter the neighboring amagmatic zones to the north and south. The relationship between gravity anomalies, vent density, and fault orientations may indicate in a broad sense the strength of the middle and upper crust. The southern Cascade Range occupies a transition zone where horizontal stress is transferred from the northwest-southeast dextral shear of the Walker Lane belt to the east-west extension characteristic of the Cascade arc in central Oregon. Faulting along north-south strikes in the volcanically active areas indicates the east-west extensional stresses in thermally weakened crust, whereas northwest faulting between the volcanically active areas reflects the northwest trending, right lateral shear strain of the Walker Lane belt. The segmentation of the arc reflected in Quaternary magmatism may be caused by differential extension behind crustal blocks of the forearc rotating clockwise with respect to North America. In this view the volcanic centers at Mount Shasta, Medicine Lake volcano, and Lassen Peak in northern California are situated along the southern parts of the trailing edges of two distinct segments of the forearc where additional extension is implied by their differential clockwise rotation. U.S. copyright. Published in 1997 by the American Geophysical Union.

  2. Detrital Geochemical Fingerprints of Rivers Along Southern Tibet and Nepal: Implications for Erosion of the Indus-Yarlung Suture Zone and the Himalayas

    NASA Astrophysics Data System (ADS)

    Hassim, M. F. B.; Carrapa, B.; DeCelles, P. G.; Kapp, P. A.; Gehrels, G. E.

    2014-12-01

    Our detrital geochemical study of modern sand collected from tributaries of the Yarlung River in southern Tibet and the Kali Gandaki River and its tributaries in Nepal shed light on the ages and exhumation histories of source rocks within the Indus-Yarlung Suture (IYS) zone and the Himalayas. Seven sand samples from rivers along the suture zone in southern Tibet between Xigatze to the east and Mt. Kailas to the west were collected for detrital zircon U-Pb geochronologic and Apatite Fission Track (AFT) thermochronologic analyses. Zircon U-Pb ages for all rivers range between 15 and 3568 Ma. Rivers draining the northern side of the suture zone mainly yield ages between 40 and 60 Ma, similar to the age of the Gangdese magmatic arc. Samples from rivers draining the southern side of the suture zone record a Tethyan Himalayan signal characterized by age clusters at 500 Ma and 1050 Ma. Our results indicate that the ages and proportion of U-Pb zircons ages of downstream samples from tributaries of the Yarlung River directly reflect source area ages and relative area of source rock exposure in the catchment basin. Significant age components at 37 - 40 Ma, 47 - 50 Ma, 55 - 58 Ma and 94 - 97 Ma reflect episodicity in Gangdese arc magmatism. Our AFT ages show two main signals at 23-18 Ma and 12 Ma, which are in agreement with accelerated exhumation of the Gangdese batholith during these time intervals. The 23 - 18 Ma signal partly overlaps with deposition of the Kailas Formation along the suture zone and may be related to exhumation due to upper plate extension in southern Tibet in response to Indian slab rollback and/or break-off events. Detrital thermochronology of four sand samples from the Kali Gandaki River and some of its tributaries in Nepal is underway and will provide constraints on the timing of erosion of the central Nepal Himalaya.

  3. Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution

    NASA Astrophysics Data System (ADS)

    Blakely, Richard J.; Christiansen, Robert L.; Guffanti, Marianne; Wells, Ray E.; Donnelly-Nolan, Julie M.; Muffler, L. J. Patrick; Clynne, Michael A.; Smith, James G.

    1997-10-01

    Isostatic residual gravity anomalies in the southern Cascade Range of northern California and southern Oregon are spatially correlated with broad zones of Quaternary magmatism as reflected by the total volume of Quaternary volcanic products, the distribution of Quaternary vents, and the anomalously low teleseismic P wave velocities in the upper 30 km of crust. The orientation of Quaternary faults also appears to be related to gravity anomalies and volcanism in this area, trending generally north-south within the magmatic regions and northwest-southeast as they enter the neighboring amagmatic zones to the north and south. The relationship between gravity anomalies, vent density, and fault orientations may indicate in a broad sense the strength of the middle and upper crust. The southern Cascade Range occupies a transition zone where horizontal stress is transferred from the northwest-southeast dextral shear of the Walker Lane belt to the east-west extension characteristic of the Cascade arc in central Oregon. Faulting along north-south strikes in the volcanically active areas indicates the east-west extensional stresses in thermally weakened crust, whereas northwest faulting between the volcanically active areas reflects the northwest trending, right lateral shear strain of the Walker Lane belt. The segmentation of the arc reflected in Quaternary magmatism may be caused by differential extension behind crustal blocks of the forearc rotating clockwise with respect to North America. In this view the volcanic centers at Mount Shasta, Medicine Lake volcano, and Lassen Peak in northern California are situated along the southern parts of the trailing edges of two distinct segments of the forearc where additional extension is implied by their differential clockwise rotation.

  4. Enzymes oxidizing the azo dye 1-phenylazo-2-naphthol (Sudan I) and their contribution to its genotoxicity and carcinogenicity.

    PubMed

    Stiborova, Marie; Schmeiser, Heinz H; Frei, Eva; Hodek, Petr; Martinek, Vaclav

    2014-01-01

    Sudan I [1-(phenylazo)-2-naphthol, C.I. Solvent Yellow 14] is an industrial dye, which was found as a contaminant in numerous foods in several European countries. Because Sudan I has been assigned by the IARC as a Category 3 carcinogen, the European Union decreed that it cannot be utilized as food colorant in any European country. Sudan I induces the malignancies in liver and urinary bladder of rats and mice. This carcinogen has also been found to be a potent mutagen, contact allergen and sensitizer, and exhibits clastogenic properties. The oxidation of Sudan I increases its toxic effects and leads to covalent adducts in DNA. Identification of enzymatic systems that contribute to Sudan I oxidative metabolism to reactive intermediates generating such covalent DNA adducts on the one hand, and to the detoxification of this carcinogen on the other, is necessary to evaluate susceptibility to this toxicant. This review summarizes the identification of such enzymes and the molecular mechanisms of oxidation reactions elucidated to date. Human and animal cytochrome P450 (CYP) and peroxidases are capable of oxidizing Sudan I. Of the CYP enzymes, CYP1A1 is most important both in Sudan I detoxification and its bio-activation. Ring-hydroxylated metabolites and a dimer of this carcinogen were found as detoxification products of Sudan I generated with CYPs and peroxidases, respectively. Oxidative bio-activation of this azo dye catalyzed by CYPs and peroxidases leads to generation of proximate genotoxic metabolites (the CYP-catalyzed formation of the benzenediazonium cation and the peroxidase-mediated generation of one-electron oxidation products), which covalently modify DNA both in vitro and in vivo. The predominant DNA adduct generated with the benzenediazonium cation was characterized to be 8-(phenylazo)guanine. The Sudan I radical species mediated by peroxidases reacts with the -NH2 group in (deoxy)guanosine, generating the 4-[(deoxy)guanosin-N(2)-yl]Sudan I product. Sudan I

  5. A cosmogenic 10Be chronology for the local last glacial maximum and termination in the Cordillera Oriental, southern Peruvian Andes: Implications for the tropical role in global climate

    NASA Astrophysics Data System (ADS)

    Bromley, Gordon R. M.; Schaefer, Joerg M.; Hall, Brenda L.; Rademaker, Kurt M.; Putnam, Aaron E.; Todd, Claire E.; Hegland, Matthew; Winckler, Gisela; Jackson, Margaret S.; Strand, Peter D.

    2016-09-01

    Resolving patterns of tropical climate variability during and since the last glacial maximum (LGM) is fundamental to assessing the role of the tropics in global change, both on ice-age and sub-millennial timescales. Here, we present a10Be moraine chronology from the Cordillera Carabaya (14.3°S), a sub-range of the Cordillera Oriental in southern Peru, covering the LGM and the first half of the last glacial termination. Additionally, we recalculate existing 10Be ages using a new tropical high-altitude production rate in order to put our record into broader spatial context. Our results indicate that glaciers deposited a series of moraines during marine isotope stage 2, broadly synchronous with global glacier maxima, but that maximum glacier extent may have occurred prior to stage 2. Thereafter, atmospheric warming drove widespread deglaciation of the Cordillera Carabaya. A subsequent glacier resurgence culminated at ∼16,100 yrs, followed by a second period of glacier recession. Together, the observed deglaciation corresponds to Heinrich Stadial 1 (HS1: ∼18,000-14,600 yrs), during which pluvial lakes on the adjacent Peruvian-Bolivian altiplano rose to their highest levels of the late Pleistocene as a consequence of southward displacement of the inter-tropical convergence zone and intensification of the South American summer monsoon. Deglaciation in the Cordillera Carabaya also coincided with the retreat of higher-latitude mountain glaciers in the Southern Hemisphere. Our findings suggest that HS1 was characterised by atmospheric warming and indicate that deglaciation of the southern Peruvian Andes was driven by rising temperatures, despite increased precipitation. Recalculated 10Be data from other tropical Andean sites support this model. Finally, we suggest that the broadly uniform response during the LGM and termination of the glaciers examined here involved equatorial Pacific sea-surface temperature anomalies and propose a framework for testing the viability

  6. Organochlorine contaminants in blubber from stranded marine mammals collected from the Northern Oregon and Southern Washington coasts: implications for re-introducing California Condors, Gymnogyps californianus, in Oregon.

    PubMed

    Gundersen, Deke T; Duffield, Deborah A; Randall, Tina; Wintle, Nate; D'Alessandro, Dalin N; Rice, James M; Shepherdson, David

    2013-03-01

    Re-introduction of California Condors into Oregon is currently being considered, but there are concerns about the safety of potential food sources of this species. Condors are opportunistic feeders and a largely available food source for this species will be stranded marine mammal carcasses. We analyzed 37 blubber samples from 7 different marine mammal species collected from the Oregon and Southern Washington coasts for 18 organochlorine (OC) pesticides and 16 polychlorinated biphenyls (PCBs). Dichlorodiphenyldichloroethylene (DDE) was the most prevalent OC contaminant, making up more than 58 % of the total OC concentration measured. There were no significant differences in OC content between species or sexes. PMID:23275975

  7. Provenance of the Passo Feio complex, Dom Feliciano Belt: Implications for the age of supracrustal rocks of the São Gabriel Arc, southern Brazil

    NASA Astrophysics Data System (ADS)

    Lopes, Carina Graciniana; Pimentel, Marcio Martins; Philipp, Ruy Paulo; Gruber, Leonardo; Armstrong, Richard; Junges, Sergio

    2015-03-01

    The Passo Feio complex (PFC) is a sequence of metapelite, amphibolite, metavolcanic/metavolcanoclastic rocks, marble, calc-silicate rocks, quartzite and magnesium schist. It is part of the São Gabriel Terrane, a Neoproterozoic juvenile arc formed during the early stages of evolution of the Neoproterozoic Dom Feliciano Belt (DFB), in southern Brazil. This belt corresponds to the southernmost portion of the Mantiqueira Province, an important Neoproterozoic orogenic system exposed in the NNE direction along the southeastern coast of Brazil. The geotectonic significance of the original Passo Feio basin in the tectonic evolution of São Gabriel Terrene is not well understood. It has been considered as part of a passive margin sequence or as a back-arc sequence. Geochronological and isotopic data are very scarse for the Passo Feio rocks and this has hampered the better understanding of its significance in the Neoproterozoic tectonic evolution of southern Brazil. In the present study the age and significance of metasedimentary rocks of the PFC were investigated. The provenance study was carried out in four metapelite samples from the southern and northern Passo Feio complex, using U-Pb dating of detrital zircon. The results showed varied provenance patterns and zircon ages range from 3637 to 803 Ma. Paleo- and Mesoproterozoic detrital zircon grains are present in all samples, but an important Neoproterozoic population has been identified in one of them. 3.5 Ga old zircon grains form the oldest population of detrital zircon ever reported in southern Brazil. Paleoproterozoic/Archean terranes within the Rio de la Plata Craton may represent the main source of detrital sediments and this suggests that part of the Passo Feio complex might have been a passive margin sequence, developed along the northeastern margin of that paleocontinent. However, the presence of a Neoproterozoic zircon population is not consistent with derivation solely from the craton and indicates

  8. Spatio-temporal spawning and larval dynamics of a zebra mussel (Dreissena polymorpha) population in a North Texas Reservoir: implications for invasions in the southern United States

    USGS Publications Warehouse

    Churchill, Christopher John

    2013-01-01

    Zebra mussels were first observed in Texas in 2009 in a reservoir (Lake Texoma) on the Texas-Oklahoma border. In 2012, an established population was found in a near-by reservoir, Ray Roberts Lake, and in June 2013, settled mussels were detected in a third north Texas reservoir, Lake Lewisville. An established population was detected in Belton Lake in September 2013. With the exception of Louisiana, these occurrences in Texas mark the current southern extent of the range of this species in the United States. Previous studies indicate that zebra mussel populations could be affected by environmental conditions, especially increased temperatures and extreme droughts, which are characteristic of surface waters of the southern and southwestern United States. Data collected during the first three years (2010–12) of a long-term monitoring program were analyzed to determine if spatio-temporal zebra mussel spawning and larval dynamics were related to physicochemical water properties in Lake Texoma. Reproductive output of the local population was significantly related to water temperature and lake elevation. Estimated mean date of first spawn in Lake Texoma was approximately 1.5 months earlier and peak veliger densities were observed two months earlier than in Lake Erie. Annual maximum veliger density declined significantly during the study period (p < 0.0001). A population crash occurred as a result of thermal stress and variability of lake elevation. In summer 2011, water temperatures peaked at 34.3°C and lake elevation declined to the lowest level recorded during the previous 18 years, which resulted in desiccation of substantial numbers of settled mussels in littoral zones. Veliger spatial distributions were associated with physicochemical stratification characteristics. Veligers were observed in the deepest oxygenated water after lake stratification, which occurred in late spring. Results of this study indicate environmental conditions can influence variability of

  9. Ground-water geology of Kordofan Province, Sudan

    USGS Publications Warehouse

    Rodis, Harry G.; Hassan, Abdulla; Wahadan, Lutfi

    1968-01-01

    For much of Kordofan Province, surface-water supplies collected and stored in hafirs, fulas, and tebeldi trees are almost completely appropriated for present needs, and water from wells must serve as the base for future economic and cultural development. This report describes the results of a reconnaissance hydrogeologic investigation of the Province and the nature and distribution of the ground-water resources with respect to their availability for development. Kordofan Province, in central Sudan, lies within the White Nile-Nile River drainage basin. The land surface is largely a plain of low relief; jebels (hills) occur sporadically, and sandy soils are common in most areas except in the south where clayey soils predominate. Seasonal rainfall, ranging from less than 100 millimeters in the north to about 800 millimeters in the south, occurs almost entirely during the summer months, but little runoff ever reaches the Nile or White Nile Rivers. The rocks beneath the surficial depsits (Pleistocene to Recent) in the Province comprise the basement complex (Precambrian), Nawa Series (upper Paleozoic), Nubian Series (Mesozoic), laterite (lower to middle Tertiary), and the Umm Ruwaba Series (Pliocene to Pleistocene). Perennial ground-water supplies in the Province are found chiefly in five hydrologic units, each having distinct geologic or hydrologic characteristics. These units occur in Nubian or Umm Ruwaba strata or both, and the sandstone and conglomerate beds form the :principal aquifers. The water is generally under slight artesian head, and the upper surface of the zone of saturation ranges from about 50 meters to 160 meters below land surface. The surficial deposits and basement rocks are generally poor sources of ground water in most of the Province. Supplies from such sources are commonly temporary and may dissipate entirely during the dry season. Locally, however, perennial supplies are obtained from the surficial deposits and from the basement rocks. Generally

  10. Combined structural interventions for gender equality and livelihood security: a critical review of the evidence from southern and eastern Africa and the implications for young people

    PubMed Central

    Gibbs, Andrew; Willan, Samantha; Misselhorn, Alison; Mangoma, Jaqualine

    2012-01-01

    Background Young people in southern and eastern Africa remain disproportionately vulnerable to HIV with gender inequalities and livelihood insecurities being key drivers of this. Behavioural HIV prevention interventions have had weak outcomes and a new generation of structural interventions have emerged seeking to challenge the wider drivers of the HIV epidemic, including gender inequalities and livelihood insecurities. Methods We searched key academic data bases to identify interventions that simultaneously sought to strengthen people's livelihoods and transform gender relationships that had been evaluated in southern and eastern Africa. Our initial search identified 468 articles. We manually reviewed these and identified nine interventions that met our criteria for inclusion. Results We clustered the nine interventions into three groups: microfinance and gender empowerment interventions; supporting greater participation of women and girls in primary and secondary education; and gender empowerment and financial literacy interventions. We summarise the strengths and limitations of these interventions, with a particular focus on what lessons may be learnt for young people (18–24). Conclusions Our review identified three major lessons for structural interventions that sought to transform gender relationships and strengthen livelihoods: 1) interventions have a narrow conceptualisation of livelihoods, 2) there is limited involvement of men and boys in such interventions, 3) studies have typically been done in stable populations. We discuss what this means for future interventions that target young people through these methods. PMID:22713350

  11. Hyalomma ticks on northward migrating birds in southern Spain: Implications for the risk of entry of Crimean-Congo haemorrhagic fever virus to Great Britain.

    PubMed

    England, Marion E; Phipps, Paul; Medlock, Jolyon M; Atkinson, Peter M; Atkinson, Barry; Hewson, Roger; Gale, Paul

    2016-06-01

    Crimean-Congo haemorrhagic fever virus (CCHFV) is a zoonotic virus transmitted by Hyalomma ticks, the immature stages of which may be carried by migratory birds. In this study, a total of 12 Hyalomma ticks were recovered from five of 228 migratory birds trapped in Spring, 2012 in southern Spain along the East Atlantic flyway. All collected ticks tested negative for CCHFV. While most birds had zero Hyalomma ticks, two individuals had four and five ticks each and the statistical distribution of Hyalomma tick counts per bird is over-dispersed compared to the Poisson distribution, demonstrating the need for intensive sampling studies to avoid underestimating the total number of ticks. Rates of tick exchange on migratory birds during their northwards migration will affect the probability that a Hyalomma tick entering Great Britain is positive for CCHFV. Drawing on published data, evidence is presented that the latitude of a European country affects the probability of entry of Hyalomma ticks on wild birds. Further data on Hyalomma infestation rates and tick exchange rates are required along the East Atlantic flyway to further our understanding of the origin of Hyalomma ticks (i.e., Africa or southern Europe) and hence the probability of entry of CCHFV into GB. PMID:27232135

  12. Late Cretaceous protolith age and provenance of the Pelona and Orocopia Schists, southern California: Implications for evolution of the Cordilleran margin

    SciTech Connect

    Jacobson, C.E.; Barth, A.P.; Grove, M.

    2000-03-01

    The Pelona and Orocopia Schists are southern members of a eugeoclinal terrane that structurally underlies a large part of southwestern North America. Ion-microprobe U-Pb ages of >100 detrital zircons from three widely spaced samples of these two units indicate that deposition occurred after 70--80 Ma. Moreover, the distribution of zircon ages, including a significant peak centered ca. 1.7 Ga, implies a major contribution f detritus from the Mojave Desert and Transverse Ranges of southern California. Recrystallization of the schists at depths of 20--35 km occurred within 10--15 m.y. of deposition, which requires underthrusting at minimum rates of {approximately}4--12 mm/yr for reasonable thrust dips. Considering that similar processes formed the more northern Rand Schist at somewhat earlier times, results indicate a southward progression in timing of deformation for the schists' protoliths. This result is at odds with northward migration of deformation implied by the Baja British Columbia hypothesis. The age and provenance of the schist's protoliths are consistent with models that derive the schists from either the Franciscan Complex or Great Valley Group.

  13. Petrogenesis of Cretaceous adakite-like intrusions of the Gangdese Plutonic Belt, southern Tibet: Implications for mid-ocean ridge subduction and crustal growth

    NASA Astrophysics Data System (ADS)

    Zheng, Yuan-chuan; Hou, Zeng-qian; Gong, Ying-li; Liang, Wei; Sun, Qing-Zhong; Zhang, Song; Fu, Qiang; Huang, Ke-Xian; Li, Qiu-Yun; Li, Wei

    2014-03-01

    We have conducted a whole-rock geochemical, U-Pb zircon geochronological, and in situ zircon Hf-O isotopic compositional study of rocks in southern Tibet from the Langxian igneous suite (including a lamprophyre dyke, mafic enclaves, a granodiorite, and a two-mica granite) and the Nuri igneous suite (a quartz-diorite). U-Pb zircon dating indicates that the timing of crystallization of the mafic enclaves and host granodiorite of the Langxian suite are ca. 105 Ma and 102 Ma, respectively, that the Langxian lamprophyre dyke and the two-mica granite were emplaced at ca. 96 Ma and 80-76 Ma, respectively, and that the Nuri quartz-diorite was emplaced at ca. 95 Ma. With the exception of the lamprophyre dyke and mafic enclaves in the Langxian area, felsic rocks from the Langxian and Nuri igneous suites all show signs of a geochemical affinity with adakite-like rocks. The high Mg-numbers, high abundance of compatible elements, high ɛNd(t) (2.7 and 2.8) and δ18O (8.9 and 9.2‰) values, elevated zircon ɛHf(t) (11.0-17.0) values, and low 87Sr/86Sr(i) ratios (0.7040), collectively indicate that the Nuri adakite-like quartz-diorite was derived from partial melting of the low temperature altered Neo-Tethyan oceanic crust, and that these dioritic magmas subsequently interacted with peridotite as they rose upwards through the overlying mantle wedge. The observation of identical differentiation trends, similar whole-rock Sr-Nd and zircon Hf isotopic compositions, and consistently low (Dy/Yb)N ratios among the Langxian igneous suite rocks, indicates that the adakite-like granodiorite was produced by low-pressure fractional crystallization of precursor magmas now represented by the (relict) mafic enclaves. However, relatively high Al2O3 contents, low MgO, Cr and Ni contents, and low (La/Yb)N and (Dy/Yb)N values indicate that the two-mica granite was derived from partial melting of the southern Tibetan mafic lower crust in the absence of garnet, while isotopic data suggest that at

  14. Field geology, geochronology and geochemistry of mafic-ultramafic rocks from Alxa, China: Implications for Late Permian accretionary tectonics in the southern Altaids

    NASA Astrophysics Data System (ADS)

    Jianyun, Feng; Wenjiao, Xiao

    2013-04-01

    The termination of orogenesis for the southern Altaids has been controversial. Systematical investigations of field geology, geochronology and geochemistry on mafic-ultramafic rocks from the northern Alxa of the southern Altaids were conducted to address the termination controversy. The newly discriminated mafic-ultramafic rocks belt is located at Bijiertai, Honggueryulin, and Qinggele areas, stretching from west to east for about 100 km in length. All of the three rock associations contact tectonically with the adjacent metamorphic and deformed Precambrian rocks as tectonic blocks or lenses, and are composed of peridotite, pyroxenite, gabbro, and serpentinite, most of which have subjected to pronounced alteration, i.e., serpentinization and chloritization. Geochemically, the rocks are characterized by a uniform trend of compositional distribution, e.g., with low SiO2-contents (42.51-52.21 wt.%) and alkalinity (Na2O+K2O) (0.01-5.45 wt.%, mostly less than 0.8 wt.%), and enriched in MgO (7.37-43.36 wt.%), with Mg# = 52.75-91.87. As the rocks have had strong alteration and have a wide range of loss-on-ignition (LOI: 0.44-14.07 wt.%), the rocks may be subjected to considerable alteration by either sea-water or metamorphic fluid. The REE and trace element patterns for the rocks show a relatively fractionated trend with LILE enrichment and HFSE depletion, similar to that of T-MORB between N-MORB and E-MORB, indicating that the parental melt resulted from the partial melting of oceanic lithospheric mantle overprinted by fluid alteration of island-arc subsequently. The ultramafic rocks are relics derived from the magma after large degree of partial melting of the oceanic lithospheric mantle with overprinted by island-arc processes under the influence of mid-ocean-ridge magmatism. LA - ICP MS U - Pb zircon ages of gabbros from the three spots are 274 ± 3 Ma (MSWD = 0.35), 306 ± 3 Ma (MSWD = 0.49), 262 ± 5 Ma (MSWD = 1.2), respectively, representing the formation ages of

  15. The seismogenic structure of the 2013-2014 Matese seismic sequence, Southern Italy: implication for the geometry of the Apennines active extensional belt

    NASA Astrophysics Data System (ADS)

    Ferranti, L.; Milano, G.; Burrato, P.; Palano, M.; Cannavò, F.

    2015-05-01

    Seismological, geological and geodetic data have been integrated to characterize the seismogenic structure of the late 2013-early 2014 moderate energy (maximum local magnitude MLmax = 4.9) seismic sequence that struck the interior of the Matese Massif, part of the Southern Apennines active extensional belt. The sequence, heralded by a ML = 2.7 foreshock, was characterized by two main shocks with ML = 4.9 and ML = 4.2, respectively, which occurred at a depth of ˜17-18 km. The sequence was confined in the 10-20 km depth range, significantly deeper than the 1997-1998 sequence which occurred few km away on the northeastern side of the massif above ˜15 km depth. The depth distribution of the 2013-14 sequence is almost continuous, albeit a deeper (16-19 km) and a shallower (11-15 km) group of events can be distinguished, the former including the main shocks and the foreshock. The epicentral distribution formed a ˜10 km long NNW-SSE trending alignment, which almost parallels the surface trace of late Pliocene-Quaternary southwest-dipping normal faults with a poor evidence of current geological and geodetic deformation. We built an upper crustal model profile for the eastern Matese massif through integration of geological data, oil exploration well logs and seismic tomographic images. Projection of hypocentres on the profile suggests that the seismogenic volume falls mostly within the crystalline crust and subordinately within the Mesozoic sedimentary cover of Apulia, the underthrust foreland of the Southern Apennines fold and thrust belt. Geological data and the regional macroseismic field of the sequence suggest that the southwest-dipping nodal plane of the main shocks represents the rupture surface that we refer to here as the Matese fault. The major lithological discontinuity between crystalline and sedimentary rocks of Apulia likely confined upward the rupture extent of the Matese fault. Repeated coseismic failure represented by the deeper group of events in the

  16. Kinematic Evolution of fold-and-thrust Belts in the Yubei Area: Implications for the Tectonic Events of Ordovician at the Southern Tarim Basin

    NASA Astrophysics Data System (ADS)

    Zhang, Y.

    2015-12-01

    As a response to tecto-orogenic processes of the South Altun and the West Kunlun (Monlar P, 1975; He Bizhu, 2011), early Paleozoic tectonic evolution of the southern Tarim craton was distinctively one of the extensions and was followed by compression (Morris W.Leighton, 1990; Gao Zhiqian, 2015). From the late Ordovician, the Yubei area developed distinctively NE-SW trending fold-and-thrust belts in rows which were eroded and deformed through multiphase tectonic movement (Dengfa He, 2007), with similarities and dissimilarities between each other rows in many aspects, at the Southern Tarim inner basin (Fig. 1). The northern of Hetian paleo-uplift and the northwestern of NE-trending folds zone on Caledonian in Tangguzibasi depression should be favorable to the potential exploration area for the first large-scale period of hydrocarbon migration and accumulation (Brown LF, 1979). In this contribution, based on geophysical log, core and 2D/3D seismic data, we constructed its tectonic geometry morphology, controlled by detailed chronostratigraphic framework. According to the fault-related fold theory, rows of asymmetric fault-propagation folds grew in the Yubei area during the late Caledonian period, with the evidence of interpreted growth strata from the high resolution 3D seismic data (Suppe J et al., 1990). That intercontinental tecto-orogenic events from southern Tarim basin, leading to the transformation of its margins, affected inner basin at that time, modified the basin into the Tarim metacraton (Jean-Paul Liégeois, 2013; Zieglar P.A., 1998). Correlating the four tectonic groups of the identified with the axis variation of strata and fold amplitude distribution showed that fault evolution progressed in several superimposed stages: Precambrian, late Ordovician to early Carboniferous (Zhao Zongju, 2009), Carboniferous to Permian, Cenozoic. Analyzing the sedimentary development and structure evolution the tectonic paleo-geographic setting is reconstructed, providing

  17. Late Jurassic sodium-rich adakitic intrusive rocks in the southern Qiangtang terrane, central Tibet, and their implications for the Bangong-Nujiang Ocean subduction

    NASA Astrophysics Data System (ADS)

    Li, Yalin; He, Juan; Han, Zhongpeng; Wang, Chengshan; Ma, Pengfei; Zhou, Aorigele; Liu, Sheng-Ao; Xu, Ming

    2016-02-01

    The lack of magmatic records with high-quality geochronological and geochemical data in the central segment of the southern Qiangtang subterrane in central Tibet inhibits a complete understanding of the subduction polarity of the Bangong-Nujiang Ocean lithosphere during the Mesozoic. In this study, we present the zircon U-Pb age as well as geochemical and Sr-Nd-Pb isotopic data for the Late Jurassic pluton from the Kangqiong area in the central segment of the southern Qiangtang subterrane. The Kangqiong pluton primarily consists of granodiorites (SiO2 = 62.87-65.17 wt.%) and was emplaced in the Late Jurassic (147.6 ± 2.4-149.9 ± 2.1 Ma). The granodiorites display high Na2O numbers (Na2O/K2O = 1.75-2.24) as well as high MgO (2.21-3.14 wt.%) and Mg-numbers (53-58), are characterized by a low abundance of heavy rare earth elements (e.g., Yb = 1.05-1.92 ppm) and Y (12.63-17.52 ppm), and high Sr/Y (29-61) and La/Yb (14-18) ratios, which are comparable in composition to those of slab-derived adakitic rocks. The Kangqiong adakitic granodiorites have initial (87Sr/86Sr)i ratios of 0.70611 to 0.70669, negative εNd(t) values (- 1.06 to - 0.25), (206Pb/204Pb)t ratios of 18.42 to 18.47, (207Pb/204Pb)t ratios of 15.62 to 15.63, and (208Pb/204Pb)t ratios of 38.50 to 38.60. These geochemical signatures indicate that the magmas were most likely derived from the partial melting of the subducted Bangong-Nujiang oceanic crust and minor contaminants from the accretionary complex. Our results, in combination with the coeval magmatism in the western segment of the southern Qiangtang subterrane, indicate that the Bangong-Nujiang oceanic lithosphere was subducted northward beneath the Qiangtang Terrane, forming a west-east magmatic arc over 800 km during the Late Jurassic.

  18. Geochemical and Sr-Nd-Pb-Os isotopic compositions of Miocene ultrapotassic rocks in southern Tibet: Petrogenesis and implications for the regional tectonic history

    NASA Astrophysics Data System (ADS)

    Wang, BaoDi; Chen, JianLin; Xu, JiFeng; Wang, LiQuan

    2014-11-01

    Ultrapotassic lavas are widespread throughout southern Tibet and are generally thought to have formed from magmas generated by partial melting of an enriched mantle source that was metasomatized during earlier subduction events. Here, we report new geochemical and Sr-Nd-Pb-Os isotope data for Miocene ultrapotassic rocks within the Sailipu area of the western Lhasa terrane, southern Tibet. The Sailipu ultrapotassic rocks are enriched in the large ion lithophile elements relative to the high field strength elements, and have extremely radiogenic Sr (87Sr/86Sr(i) = 0.714480-0.727323), Pb (206Pb/204Pb = 18.414-18.787, 207Pb/204Pb = 15.693-15.749, 208Pb/204Pb = 39.439-39.765), and Os isotopic signatures (187Os/188Os(i) = 0.1095-0.37454), and unradiogenic Nd (εNd(t) = - 11.5 to - 15.2) isotopic compositions. These geochemical and isotopic characteristics, coupled with high K2O (> 5 wt.%) and MgO (5.20-13.70 wt.%) concentrations, Mg# values of 68-76, high Rb/Sr (0.13-0.95) and low Ba/Rb (3.33-12.3) ratios, and the relatively low Os contents and radiogenic Os isotopic compositions of the Sailipu ultrapotassic rocks, do not support any significant crustal contamination. Instead, we consider these rocks to be analogous to the Cenozoic ultrapotassic rocks from Italy and the Balkans, suggesting that they were produced by interaction between melts derived from phlogopite-rich clinopyroxene veins and surrounding peridotitic mantle material. The Sailipu ultrapotassic rocks can be divided into type-1 and type-2 suites based on differences in major and trace element concentrations, and isotopic compositions. Type-1 ultrapotassic rocks are relatively enriched in the heavy rare earth elements, most likely as a result of interaction between melts derived from phlogopite-rich clinopyroxene veins and the surrounding spinel-bearing peridotite material, whereas the type-2 rocks are enriched in rare earth elements and have high (Gd/Yb)N values (8.3-12.2), both of which are indicative of

  19. Confluence of the White and Blue Nile Rivers at Khartoum, Sudan

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Blue Nile River flowing from Lake Tana to the east and the larger White Nile River flowing from the Rift Valley region combine to form the Nile River at Khartoum, the capital city of Sudan (15.5N, 33.0E). The rivers normally flow out of phase as a result of the differing maximum precipitation periods of their watersheds. The differing flow periods allows longer use of the river for agriculture irrigation in the fields south of the city.

  20. Sudan stain of fecal fat: new insight into an old test.

    PubMed

    Khouri, M R; Huang, G; Shiau, Y F

    1989-02-01

    The 72-h fecal fat determination is used as the gold standard to document the presence of steatorrhea. Although the Sudan stain for fecal fat is advocated as a sensitive screening test, a quantitative correlation between the 72-h fecal fat quantitation and the fecal Sudan stain is lacking. This study was designed to examine the staining properties of different classes of purified lipids in an experimentally defined artificial matrix, and to elucidate the reasons for the lack of quantitative correlation between these two tests. Our results indicate that the "neutral fat" stain without acidification or heating identifies triglyceride; and at an appropriate pH, the "neutral stain" also identifies fatty acid. The "split fat" stain with acidification and heating identifies both triglyceride and fatty acid. After acidification, fatty acid soaps are converted to the nonionized fatty acid. Thus, fatty acid soaps can be identified indirectly as fat droplets that are stained by the split fat stain. Although cholesterol is stained with Sudan stain after heating, upon cooling, cholesterol forms crystals of anhydrous cholesterol, making its staining pattern distinct. Neither the neutral fat nor the split fat stain can detect phospholipid or cholesteryl ester. The 72-h fecal fat determination is a measure of the total fatty acid content after a specimen is saponified. The resulting fatty acids are derived from a variety of endogenous and exogenous sources, including free fatty acids, soaps of fatty acids, triglycerides, cholesterol esters, and phospholipids. Therefore, the 72-h fecal fat quantitation does not differentiate between the primary sources of the measured fatty acid. It is concluded that the 72-h fecal fat determination is not specific for documenting triglyceride (fat) malabsorption. Until new methods are developed that specifically measure fecal triglyceride and fatty acid, the Sudan stain of fecal fat appears to be a more specific method for detecting the presence

  1. 76 FR 69612 - Amendment to the International Traffic in Arms Regulations: Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    .... 744 (22 U.S.C. 2752, 2778, 2780, 2791, and 2797); E.O. 11958, 42 FR 4311; 3 CFR, 1977 Comp., p.79; 22 U.S.C. 2651a; 22 U.S.C. 287c; E.O. 12918, 59 FR 28205; 3 CFR, 1994 Comp., p.899; Sec. 1225, Pub. L... Part 126 RIN 1400-AC93 Amendment to the International Traffic in Arms Regulations: Sudan...

  2. Levels of pesticides residues in the White Nile water in the Sudan.

    PubMed

    Nesser, Gibreel A A; Abdelbagi, Azhari O; Hammad, Ahmed Mohammed Ali; Tagelseed, Mirghani; Laing, Mark D

    2016-06-01

    Twenty-two commonly used pesticides were monitored during autumn, winter, and summer of 2004-2005 in 27 water samples from three sites along the White Nile in Sudan (former Sudan). Sites were selected to reflect pesticides gathered from drainage canals in central Sudan and from upstream sources. Collected samples were extracted and subjected to gas chromatographic analysis. Pesticides levels were measured in nanograms per liter. Pesticides residues were detected in 96 % of the samples with a total residue burden of 4132.6 ng L(-1), and an overall mean concentration and range of 50.99 and not detected-1570 ng L(-1), respectively. Ororganochlorines were the most frequently detected contaminants, which were found in 70 % of the samples, causing a total burden of 2852.8 ng L(-1), followed by pyrethroids 15 % of the samples, with a total burden of 926.5 ng L(-1). The tested herbicides were detected in ˂4 % of the samples with a total burden of 353.3 ng L(-1), while organophosphorus levels were below the detection limit. The most frequent contaminants were the following: heptachlor and its epoxide (52 % of samples), followed by DDTs (dichlorodiphenyltrichloroethanes) (DDT and DDE, in 19 % of the samples), cypermethrin and fenvalerate (in 11 % of the samples), and pendimethalin (in <4 % of the samples). Residues of hexachlorocyclohexane (HCH) isomers (α, β, γ and δ), endosulfan (α and β), p, p-DDD, λ cyhalothrin, deltamethrin, and oxyfluorfen were not detected in the analyzed samples. Generally, levels were least in autumn, and followed by summer and winter. Sources of contamination might include agricultural lands in central Sudan and upstream sources. Both recent and old contaminations were indicated. PMID:27230426

  3. Climate change, conflict and development in Sudan: global neo-Malthusian narratives and local power struggles.

    PubMed

    Verhoeven, Harry

    2011-01-01

    Dystopian accounts of climate change posit that it will lead to more conflict, causing state failure and mass population movements. Yet these narratives are both theoretically and empirically problematic: the conflict–environment hypothesis merges a global securitization agenda with local manipulations of Northern fears about the state of planetary ecology. Sudan has experienced how damaging this fusion of wishful thinking, power politics and top-down development can be. In the 1970s, global resource scarcity concerns were used locally to impose the fata morgana of Sudan as an Arab-African breadbasket: in the name of development, violent evictions of local communities contributed to Sudan's second civil war and associated famines. Today, Darfur has been labelled ‘the world's first climate change conflict’, masking the long-term political-economic dynamics and Sudanese agency underpinning the crisis. Simultaneously, the global food crisis is instrumentalized to launch a dam programme and agricultural revival that claim to be African answers to resource scarcity. The winners, however, are Sudan's globalized Islamist elites and foreign investors, whilst the livelihoods of local communities are undermined. Important links exist between climatic developments and security, but global Malthusian narratives about state failure and conflict are dangerously susceptible to manipulations by national elites; the practical outcomes decrease rather than increase human security. In the climate change era, the breakdown of institutions and associated violence is often not an unfortunate failure of the old system due to environmental shock, but a strategy of elites in wider processes of power and wealth accumulation and contestation.

  4. Agricultural fields, Khartoum, Sudan, Africa Description: This herringbone pattern of irrigated

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) was imaged with infrared film as part an experiment to compare the merits of color film versus color infrared film. Color film presents the image as it appears to the eye whereas color infrared film has an excellent haze penetration and vegetation definition capability. See color film image STS049-77-072 for a detailed scene description.

  5. Uranium series disequilibria in ground waters from a fractured bedrock aquifer (Morungaba Granitoids--Southern Brazil): implications to the hydrochemical behavior of dissolved U and Ra.

    PubMed

    Reyes, Erika; Marques, Leila S

    2008-10-01

    Activity concentrations of dissolved (234)U, (238)U, (226)Ra and (228)Ra were determined in ground waters from two deep wells drilled in Morungaba Granitoids (Southern Brazil). Sampling was done monthly for little longer than 1 year. Significant disequilibrium between (238)U, (234)U and (226)Ra were observed in all samples. The variation of (238)U and (234)U activity concentrations and (234)U/(238)U activity ratios is related to seasonal changes. Although the distance between the two wells is short (about 900 m), systematic differences of activity concentrations of U isotopes, as well as of (234)U/(238)U, (226)Ra/(234)U and (228)Ra/(226)Ra activity ratios were noticed, indicating distinct host rock-water interactions. Slightly acidic ground water percolation through heterogeneous host rock, associated with different recharge processes, may explain uranium and radium isotope behavior.

  6. A New Estimate for Total Offset on the Southern San Andreas Fault: Implications for Cumulative Plate Boundary Shear in the Northern Gulf of California

    NASA Astrophysics Data System (ADS)

    Darin, M. H.; Dorsey, R. J.

    2012-12-01

    Development of a consistent and balanced tectonic reconstruction for the late Cenozoic San Andreas fault (SAF) in southern California has been hindered for decades by incompatible estimates of total dextral offset based on different geologic cross-fault markers. The older estimate of 240-270 km is based on offset fluvial conglomerates of the middle Miocene Mint Canyon and Caliente Formations west of the SAF from their presumed source area in the northern Chocolate Mountains NE of the SAF (Ehlig et al., 1975; Ehlert, 2003). The second widely cited offset marker is a distinctive Triassic megaporphyritic monzogranite that has been offset 160 ± 10 km between Liebre Mountain west of the SAF and the San Bernadino Mountains (Matti and Morton, 1993). In this analysis we use existing paleocurrent data and late Miocene clockwise rotation in the eastern Transverse Ranges (ETR) to re-assess the orientation of the piercing line used in the 240 km-correlation, and present a palinspastic reconstruction that satisfies all existing geologic constraints. Our reconstruction of the Mint Canyon piercing line reduces the original estimate of 240-270 km to 195 ± 15 km of cumulative right-lateral slip on the southern SAF (sensu stricto), which is consistent with other published estimates of 185 ± 20 km based on correlative basement terranes in the Salton Trough region. Our estimate of ~195 km is consistent with the lower estimate of ~160 km on the Mojave segment because transform-parallel extension along the southwestern boundary of the ETR during transrotation produces ~25-40 km of displacement that does not affect offset markers of the Liebre/San Bernadino correlation located northwest of the ETR rotating domain. Reconciliation of these disparate estimates places an important new constraint on the total plate boundary shear that is likely accommodated in the adjacent northern Gulf of California. Global plate circuit models require ~650 km of cumulative Pacific-North America (PAC

  7. New paleomagnetic data from Late Neoproterozoic sedimentary successions in Southern Urals, Russia: implications for the Late Neoproterozoic paleogeography of the Iapetan realm

    NASA Astrophysics Data System (ADS)

    Lubnina, Natalia V.; Pisarevsky, Sergei A.; Puchkov, Victor N.; Kozlov, Vjacheslav I.; Sergeeva, Nina D.

    2014-07-01

    We present the results of paleomagnetic study of Ediacaran sedimentary successions from the Southern Urals. The analysis of the sedimentary rocks of the Krivaya Luka, Kurgashlya and Bakeevo Formations reveal stable mid-temperature and high-temperature remanence components. Mid-temperature components were acquired during Devonian (Bakeevo Formation) and Late Carboniferous-Early Permian remagnetization events. The high-temperature components in Kurgashlya and Bakeevo Formations are interpreted to be primary, because they are supported by a positive conglomerate test (Bakeevo Formation) and magnetostratigraphic pattern (Kurgashlya Formation). The high-temperature component in the Krivaya Luka Formation is interpreted to be a Late Ediacaran overprint. Our new paleomagnetic poles together with some previously published Ediacaran poles from Baltica and Laurentia are used herein to produce a series of paleogeographic reconstructions of the opening of the Iapetus Ocean.

  8. Geology of the Eel River basin and adjacent region: Implications for late Cenozoic tectonics of the southern Cascadia subduction zone and Mendocino triple junction

    SciTech Connect

    Clarke, S.H. Jr. )

    1992-02-01

    Two upper Cenozoic depositional sequences of principally marine strata about 4,000 m thick overlie accreted basement terranes of the Central and Coastal belts of the Franciscan Complex in the onshore-offshore Eel River basin of northwestern California. The older depositional sequence is early to middle Miocene in age and represents slope basin and slope-blanket deposition, whereas the younger sequence, later Miocene to middle Pleistocene in age, consists largely of forearc basin deposits. Youthful tectonic activity related to Gorda-North American plate convergence indicates an active Cascadia subduction zone and strong partial coupling between these plates. Structures of the northeastern margin of the Eel River basin are principally north-northwest-trending, east-northeast-dipping thrust and reverse faults that form imbricate thrust fans. The Coastal belt fault, the early Tertiary accretionary suture between the Franciscan Central and Coastal belts, can be traced from Arcata Bay northward offshore to the southern Oregon border. It is tentatively extended farther northward based on aeromagnetic data to an offshore position west of Cape Blanco. Thereafter, it may coincide with the offshore Fulmar fault. The Cascadia subduction zone (CSZ) does not join the Mendocino transform fault at the commonly depicted offshore location of the Mendocino triple junction (MTJ). Instead, the CSZ extends southeastward around the southern Eel River basin and shoreward along Mendocino Canyon to join the Petrolia shear zone. Similarly, the Mendocino fault may extend shoreward via Mattole Canyon and join the Cooskie shear zone. These two shear zones intersect onshore north of the King Range, and the area of their intersection is the probable location of the MTJ.

  9. New [sup 40]Ar/[sup 39]Ar mica ages from eastern New Hampshire and southern Maine: Implications for the exhumation history of the region

    SciTech Connect

    Lux, D.R.; West, D.P. Jr. . Dept. of Geological Science)

    1993-03-01

    It has long been recognized that micas from the high-grade metamorphic terrane of Maine and New Hampshire have anomalously young K-Ar ages. Furthermore, ages show systematic spatial patterns. Samples from western New Hampshire are youngest and become progressively older towards the east. In the Kearsarge-Central Maine Synclinorium (KCMS) of western Maine, ages are oldest along the northern terminus of high grade metamorphism and become progressively younger towards the southwest. In order to understand this peculiar relationship, micas from 20 sites in eastern New Hampshire and southern Maine were dated by the [sup 40]Ar/[sup 39]Ar method. The following relationships are observed: (1) Micas from the KCMS of southern New Hampshire have Permo-Carboniferous ages and coexisting micas are highly discordant, (2) micas from within or very near the Massabesic Gneiss Complex have young ages ([approximately]240--250 Ma) and show little to no discordance, (3) with one exception, micas from south of the Sebago batholith in Maine are also young ([approximately]240--250 Ma) and show little to no discordance. North of the Sebago batholith the transition to older micas is gradual. Mica ages from the Massabesic Gneiss Complex are younger than in surrounding regions and the transition to older ages roughly coincides with the Campbell Hill and Flint Hill faults. Outside the zone of young micas, cooling curves are concave upward for the same temperature interval. The young micas are concordant indicating rapid cooling but they are [approximately]40 Ma younger than the time of Late Paleozoic metamorphism. Therefore the young ages cannot be explained by rapid post-metamorphic cooling. The authors believe the accelerated cooling is the result of regional tectonic exhumation related to the earliest stages of rifting associated with opening of the Atlantic.

  10. Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt

    NASA Astrophysics Data System (ADS)

    Yin, Jiyuan; Chen, Wen; Xiao, Wenjiao; Yuan, Chao; Long, Xiaoping; Cai, Keda; Zhang, Bin

    2016-07-01

    Carboniferous granitic rocks are wide spread in the western Tianshan, but their tectonic contexts remain controversial. We present zircon U-Pb age, major element, trace element, and in situ zircon Hf isotopic data for the Qiongkusitai granodiorites from the southern part of the Yili block in the western Tianshan. The granodiorites were emplaced in the Late Carboniferous (ca. 314 Ma) and are characterized by high SiO2 (62.1-65.7 wt.%), high Sr (376-485 ppm), low Y (13.7-17.7 ppm) and low Yb (1.34-1.81 ppm) with Sr/Y ratios of 23-34. Such characteristics imply adakitic affinities. Their low concentrations of Cr (3.85-6.75 ppm), Co (7.63-10.7 ppm) and Ni (2.94-6.80 ppm) suggest little, if any, interaction with a mantle source. Compared to the thickened lower crustal-derived adakitic rocks, the relatively low Nb/Ta ratios of the Qiongkusitai adakitic granodiorites indicate that they were probably generated by partial melting of amphibolite facies rocks, but not eclogite facies rocks. The Qiongkusitai adakitic granodiorites have positive zircon εHf(t) values of +0.7 to +5.1 and TDM2 of 1.28-1.68 Ga, and they are interpreted as being derived from remelting of amphibolite facies Mesoproterozoic basement with an input of juvenile material. Late Carboniferous magmatism in the western Tianshan was possibly triggered by asthenospheric upwelling as a result of the roll-back of the subducted southern Tianshan oceanic lithosphere.

  11. Petrogenesis of early Jurassic basalts in southern Jiangxi Province, South China: Implications for the thermal state of the Mesozoic mantle beneath South China

    NASA Astrophysics Data System (ADS)

    Cen, Tao; Li, Wu-xian; Wang, Xuan-ce; Pang, Chong-jin; Li, Zheng-xiang; Xing, Guang-fu; Zhao, Xi-lin; Tao, Jihua

    2016-07-01

    Early Jurassic bimodal volcanic and intrusive rocks in southern South China show distinct associations and distribution patterns in comparison with those of the Middle Jurassic and Cretaceous rocks in the area. It is widely accepted that these rocks formed in an extensional setting, although the timing of the onset and the tectonic driver for extension are debated. Here, we present systematic LA-ICP-MS zircon U-Pb ages, whole-rock geochemistry and Sr-Nd isotope data for bimodal volcanic rocks from the Changpu Formation in the Changpu-Baimianshi and Dongkeng-Linjiang basins in southern Jiangxi Province, South China. Zircon U-Pb ages indicate that the bimodal volcanic rocks erupted at ca. 190 Ma, contemporaneous with the Fankeng basalts (~ 183 Ma). A compilation of geochronological results demonstrates that basin-scale basaltic eruptions occurred during the Early Jurassic within a relatively short interval (< 5 Ma). These Early Jurassic basalts have tholeiitic compositions and OIB-like trace element distribution patterns. Geochemical analyses show that the basalts were derived from depleted asthenospheric mantle, dominated by a volatile-free peridotite source. The calculated primary melt compositions suggest that the basalts formed at 1.9-2.1 GPa, with melting temperatures of 1378 °C-1405 °C and a mantle potential temperature (TP) ranging from 1383 °C to 1407 °C. The temperature range is somewhat hotter than normal mid-ocean-basalt (MORB) mantle but similar to an intra-plate continental mantle setting, such as the Basin and Range Province in western North America. This study provides an important constraint on the Early Jurassic mantle thermal state beneath South China.

  12. The upper lithostratigraphic unit of ANDRILL AND-2A core (Southern McMurdo Sound, Antarctica): local Pleistocene volcanic sources, paleoenvironmental implications and subsidence in the southern Victoria Land Basin

    NASA Astrophysics Data System (ADS)

    Del Carlo, P.; Panter, K. S.; Bassett, K. N.; Bracciali, L.; di Vincenzo, G.; Rocchi, S.

    2009-12-01

    We report results from the study of the uppermost 37 meters of the Southern McMurdo Sound (SMS) AND-2A drillcore, corresponding to the lithostratigraphic unit 1 (LSU 1), the most volcanogenic unit within the core. Nearly all of LSU 1 consists of volcanic breccia and sandstone that is a mixture of near primary volcanic material dominated by lava and vitric clasts with minor exotic material derived from distal basement sources. Lava clasts and glass are mafic and range from strongly alkaline (basanite, tephrite) to moderately alkaline (alkali basalt, hawaiite) compositions that are similar to nearby land deposits. 40Ar-39Ar laser step-heating analyses on groundmass separated from lava clasts yield Pleistocene ages (692±38 and 793±63, ±2σ internal errors). Volcanoes of the Dailey Island group, located ~13 km SW of the drillsite, are a possible source for the volcanic materials based on their close proximity, similar composition and age. A basanite lava flow on Juergens Island yields a comparable Pleistocene age of 775±22 ka. Yet there is evidence to suggest that the volcanic source is much closer to the drillsite and that the sediments were deposited in much shallower water relative to the present-day water depth of 384 mbsl. Evidence for local volcanic activity is based in part on the common occurrence of delicate vitriclasts (e.g. glass shards and Pele’s hair) and a minimally reworked ~2 meter thick monomict breccia that is interpreted to have formed by autobrecciating lava. In addition, conical-shaped seamounts and high frequency magnetic anomalies encompass the drillsite and extend south including the volcanoes of the Dailey Islands. Sedimentary features and structures indicate shallow water sedimentation for the whole of LSU 1. Rippled asymmetric cross-laminated sands and hummocky cross-stratification occur intermittently throughout LSU 1 and indicate water depths shallower than 100 meters. The occurrence of ooliths and layers containing siderite and Fe

  13. Phylogenetic analysis of some Newcastle disease virus isolates from the Sudan.

    PubMed

    Elmardi, N A; Bakheit, M A; Khalafalla, A I

    2016-01-01

    A reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify 1412 bp of the fusion protein gene (F gene) of four Newcastle disease virus (NDV) isolates; two velogenic (TY-1/90 and DIK-90) and two lentogenic isolates (Dongla 88/1 and GD.S.1). Following sequencing, nucleotide sequences were annotated and 894 bp were compared phylogenetically with those from strains previously reported in the Sudan and the virus strains published on the GenBank. It could be demonstrated that TY-1/90 and DIK-90 strains belong to the genotype VI of NDV and are in close genetic relationship to sub- genotype VIb. TY-1/90 and DIK-90 strains were observed to be genetically unrelated to the earlier Sudanese isolates of 1970/80s and the late of 2000s suggesting a different origin. The close genetic relationship to the European and African pigeon paramyxovirus type 1 (PPMV-1) suggests a common ancestor. Dongola, GD.S.1 strains were classified into genotype II that comprises non-pathogenic lentogenic NDV strains. The present genetic classification of NDV isolates of the Sudan provides valuable information on genotypes of NDV. Further molecular epidemiological investigations of the recent outbreaks of Newcastle disease in the Sudan are needed in order to improve the efficiency of control strategies and vaccine development. PMID:27419101

  14. Phylogenetic analysis of some Newcastle disease virus isolates from the Sudan

    PubMed Central

    Elmardi, N.A.; Bakheit, M.A.; Khalafalla, A.I.

    2016-01-01

    A reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify 1412 bp of the fusion protein gene (F gene) of four Newcastle disease virus (NDV) isolates; two velogenic (TY-1/90 and DIK-90) and two lentogenic isolates (Dongla 88/1 and GD.S.1). Following sequencing, nucleotide sequences were annotated and 894 bp were compared phylogenetically with those from strains previously reported in the Sudan and the virus strains published on the GenBank. It could be demonstrated that TY-1/90 and DIK-90 strains belong to the genotype VI of NDV and are in close genetic relationship to sub- genotype VIb. TY-1/90 and DIK-90 strains were observed to be genetically unrelated to the earlier Sudanese isolates of 1970/80s and the late of 2000s suggesting a different origin. The close genetic relationship to the European and African pigeon paramyxovirus type 1 (PPMV-1) suggests a common ancestor. Dongola, GD.S.1 strains were classified into genotype II that comprises non-pathogenic lentogenic NDV strains. The present genetic classification of NDV isolates of the Sudan provides valuable information on genotypes of NDV. Further molecular epidemiological investigations of the recent outbreaks of Newcastle disease in the Sudan are needed in order to improve the efficiency of control strategies and vaccine development. PMID:27419101

  15. [Leucosis diagnosis in cattle using the Sudan black B staining method on granulocytes and monocytes].

    PubMed

    Rademacher, R; Vanásek, J; Sodomková, D

    1979-11-01

    In the peripheral blood of healthy cattle and cattle suffering from leucosis a positive reaction with Sudan black B was found in neutrophilic and eosinophilic granulocytes: in healthy cattle at an intensity from ++ to ++++, and in cattle suffering from leucosis it was somewhat slighter (++ to +++). This finding can, to a certain extent, help in the distinguishing of reactive lymphocytosis from the leucosis of cattle. Compared with granulocytes the reaction of monocytes is markedly weaker: in healthy cattle at an intensity from 0 to (++), and in diseased cattle from 0 to (+++). In the bone marrow there is a significantly weaker reaction to Sudan black B in the group of large cells (neutrophilic and eosinophilic promyelocytes and myelocytes); in the group of healthy and diseases cattle the reaction is weaker than in neutrophilic and eosinophilic granulocytes of the peripheral blood. The reaction obtained with Sudan black B for lipids can be used as an aid for the distinguishing of cells of the myeloid, monocytic, and lymphoid order of peripheral blood and bone marrow in cattle leucosis. PMID:92849

  16. Linking Satellite Derived Land Surface Temperature with Cholera: A Case Study for South Sudan

    NASA Astrophysics Data System (ADS)

    Aldaach, H. S. V.; Jutla, A.; Akanda, A. S.; Colwell, R. R.

    2014-12-01

    A sudden onset of cholera in South Sudan, in April 2014 in Northern Bari in Juba town resulted in more than 400 cholera cases after four weeks of initial outbreak with a case of fatality rate of CFR 5.4%. The total number of reported cholera cases for the period of April to July, 2014 were 5,141 including 114 deaths. With the limited efficacy of cholera vaccines, it is necessary to develop mechanisms to predict cholera occurrence and thereafter devise intervention strategies for mitigating impacts of the disease. Hydroclimatic processes, primarily precipitation and air temperature are related to epidemic and episodic outbreak of cholera. However, due to coarse resolution of both datasets, it is not possible to precisely locate the geographical location of disease. Here, using Land Surface Temperature (LST) from MODIS sensors, we have developed an algorithm to identify regions susceptible for cholera. Conditions for occurrence of cholera were detectable at least one month in advance in South Sudan and were statistically sensitive to hydroclimatic anomalies of land surface and air temperature, and precipitation. Our results indicate significant spatial and temporal averaging required to infer usable information from LST over South Sudan. Preliminary results that geographically location of cholera outbreak was identifiable within 1km resolution of the LST data.

  17. Migration, unemployment and the urban labour market. A case study of the Sudan.

    PubMed

    Oberai, A S

    1977-01-01

    Investigation of migration, unemployment, and the urban labor in Sudan was based on the Household Socioeconomic Survey of Greater Khartoum, conducted in October-November 1974. The survey sample consisted of 15,339 persons, 8904 of whom were natives of the 3 towns (Greater Khartoum) and 6435 were immigrants. Among the latter were 976 children below 12 years of age from whom no migration information was collected. Adult migrants were further subdivided into those who had migrated during the 5 years preceding the survey (947) and those who had migrated 5 or more years previously (4512). During the 5 years preceding the survey, the rate of migration into the 3 towns was of the order of 2.2% per annum. Over 80% of the migrants came from 9 of the 12 northern and central provinces. The 3 southern provinces contributed few migrants to the area. 47% of the recent migrants stated that their last place of residence had been a rural area; 53% reported an urban area. Among recent migrants, 69% of the males and 67% of the females were between the ages of 15-29. Only 4% of the males and 11% of the females were over 50. The migrants had a significantly higher level of education than the average population in the northern and central provinces where most of them originated, but this does not mean that they were necessarily better educated than the native population of the 3 towns. Of the 947 recent migrants, 354 had been working before the move. Of these the great majority, 73% had been in agriculture, 8% in services, 6% in trade, and 3% in construction. 18% of those working before the move were private employees, 6% government employees, and the remaining 76% either self employed or unpaid family workers. In this last category 82% of the self employed and 97% of the unpaid family workers had been in agriculture. The principal pull factors seemed to have been higher average annual earnings, job availability, better educational opportunities, and the low cost of migration due to the

  18. Method development and survey of Sudan I–IV in palm oil and chilli spices in the Washington, DC, area

    PubMed Central

    Genualdi, Susie; MacMahon, Shaun; Robbins, Katherine; Farris, Samantha; Shyong, Nicole; DeJager, Lowri

    2016-01-01

    Sudan I, II, III and IV dyes are banned for use as food colorants in the United States and European Union because they are toxic and carcinogenic. These dyes have been illegally used as food additives in products such as chilli spices and palm oil to enhance their red colour. From 2003 to 2005, the European Union made a series of decisions requiring chilli spices and palm oil imported to the European Union to contain analytical reports declaring them free of Sudan I–IV. In order for the USFDA to investigate the adulteration of palm oil and chilli spices with unapproved colour additives in the United States, a method was developed for the extraction and analysis of Sudan dyes in palm oil, and previous methods were validated for Sudan dyes in chilli spices. Both LC-DAD and LC-MS/MS methods were examined for their limitations and effectiveness in identifying adulterated samples. Method validation was performed for both chilli spices and palm oil by spiking samples known to be free of Sudan dyes at concentrations close to the limit of detection. Reproducibility, matrix effects, and selectivity of the method were also investigated. Additionally, for the first time a survey of palm oil and chilli spices was performed in the United States, specifically in the Washington, DC, area. Illegal dyes, primarily Sudan IV, were detected in palm oil at concentrations from 150 to 24 000 ng ml−1. Low concentrations (< 21 μg kg−1) of Sudan dyes were found in 11 out of 57 spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration. PMID:26824489

  19. Method development and survey of Sudan I-IV in palm oil and chilli spices in the Washington, DC, area.

    PubMed

    Genualdi, Susie; MacMahon, Shaun; Robbins, Katherine; Farris, Samantha; Shyong, Nicole; DeJager, Lowri

    2016-01-01

    Sudan I, II, III and IV dyes are banned for use as food colorants in the United States and European Union because they are toxic and carcinogenic. These dyes have been illegally used as food additives in products such as chilli spices and palm oil to enhance their red colour. From 2003 to 2005, the European Union made a series of decisions requiring chilli spices and palm oil imported to the European Union to contain analytical reports declaring them free of Sudan I-IV. In order for the USFDA to investigate the adulteration of palm oil and chilli spices with unapproved colour additives in the United States, a method was developed for the extraction and analysis of Sudan dyes in palm oil, and previous methods were validated for Sudan dyes in chilli spices. Both LC-DAD and LC-MS/MS methods were examined for their limitations and effectiveness in identifying adulterated samples. Method validation was performed for both chilli spices and palm oil by spiking samples known to be free of Sudan dyes at concentrations close to the limit of detection. Reproducibility, matrix effects, and selectivity of the method were also investigated. Additionally, for the first time a survey of palm oil and chilli spices was performed in the United States, specifically in the Washington, DC, area. Illegal dyes, primarily Sudan IV, were detected in palm oil at concentrations from 150 to 24 000 ng ml(-1). Low concentrations (< 21 µg kg(-1)) of Sudan dyes were found in 11 out of 57 spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration.

  20. Geography and correlates of attitude toward Female Genital Mutilation (FGM) in Sudan: What can we learn from successive Sudan opinion poll data?

    PubMed

    Hamilton, Alexander; Kandala, Ngianga-Bakwin

    2016-02-01

    In Sudan, prevalence of FGM is declining; likely as a result of changing attitude surrounding FGM, as more women believe the practice should be discontinued amid growing awareness about its health dangers. DFID Sudan opinion poll data collected from 2012 to 2014 was used. Bayesian geo-additive mixed models were used to map the spatial distribution of the likelihood of pro-FGM attitude at the state-level accounting for associated risk factors. During 2012 to 2014, the overall proportion of pro-FGM was 27.5% and 18.3% respectively with striking variations within states. People with pro-FGM attitude were more likely to be un-educated, living in rural settings with strong tribal identity. Individuals from Darfur were more likely to be pro-FGM when compared to the North state. The decrease in the practice of cutting observed between the 2006 and 2010 Sudanese Household Surveys and the resulting shift in attitude make a compelling case for public health policy to eradicate the FGM practice. PMID:26919756

  1. Geography and correlates of attitude toward Female Genital Mutilation (FGM) in Sudan: What can we learn from successive Sudan opinion poll data?

    PubMed

    Hamilton, Alexander; Kandala, Ngianga-Bakwin

    2016-02-01

    In Sudan, prevalence of FGM is declining; likely as a result of changing attitude surrounding FGM, as more women believe the practice should be discontinued amid growing awareness about its health dangers. DFID Sudan opinion poll data collected from 2012 to 2014 was used. Bayesian geo-additive mixed models were used to map the spatial distribution of the likelihood of pro-FGM attitude at the state-level accounting for associated risk factors. During 2012 to 2014, the overall proportion of pro-FGM was 27.5% and 18.3% respectively with striking variations within states. People with pro-FGM attitude were more likely to be un-educated, living in rural settings with strong tribal identity. Individuals from Darfur were more likely to be pro-FGM when compared to the North state. The decrease in the practice of cutting observed between the 2006 and 2010 Sudanese Household Surveys and the resulting shift in attitude make a compelling case for public health policy to eradicate the FGM practice.

  2. Determination of Sudan I in paprika powder by molecularly imprinted polymers-thin layer chromatography-surface enhanced Raman spectroscopic biosensor.

    PubMed

    Gao, Fang; Hu, Yaxi; Chen, Da; Li-Chan, Eunice C Y; Grant, Edward; Lu, Xiaonan

    2015-10-01

    Sudan I is a carcinogenic and mutagenic azo-compound that has been utilized as a common adulterant in spice and spice blends to impart a desirable red color to foods. A novel biosensor combining molecularly imprinted polymers (MIPs), thin layer chromatography (TLC) and surface enhanced Raman spectroscopy (SERS) could determine Sudan I levels in paprika powder to 1 ppm (or 2 ng/spot). Sudan I spiked paprika extracts (spiking levels: 0, 1, 5, 10, 40, 70 and 100 ppm) were prepared. Sudan I imprinted polymers were synthesized by employing the interaction between Sudan I (template) and methacrylic acid (functional monomer), followed by washing to remove Sudan I leaving the Sudan I-binding sites exposed. MIPs were used as a stationary phase for TLC and could selectively retain Sudan I at the original spot with little interference. A gold colloid SERS substrate could enhance Raman intensity for Sudan I in this MIP-TLC system. Principal component analysis plot and partial least squares regression (R(2)=0.978) models were constructed and a linear regression model (R(2)=0.983) correlated spiking levels (5, 10, 40, 70 and 100 ppm) with the peak intensities (721 cm(-1)) of Sudan I SERS spectra. Both separation (30-40s) and detection (1s or 0.1s) were extremely fast by using both commercial bench-top and custom made portable Raman spectrometers. This biosensor can be applied as a rapid, low-cost and reliable tool for screening Sudan I adulteration in foods.

  3. Determination of Sudan I in paprika powder by molecularly imprinted polymers-thin layer chromatography-surface enhanced Raman spectroscopic biosensor.

    PubMed

    Gao, Fang; Hu, Yaxi; Chen, Da; Li-Chan, Eunice C Y; Grant, Edward; Lu, Xiaonan

    2015-10-01

    Sudan I is a carcinogenic and mutagenic azo-compound that has been utilized as a common adulterant in spice and spice blends to impart a desirable red color to foods. A novel biosensor combining molecularly imprinted polymers (MIPs), thin layer chromatography (TLC) and surface enhanced Raman spectroscopy (SERS) could determine Sudan I levels in paprika powder to 1 ppm (or 2 ng/spot). Sudan I spiked paprika extracts (spiking levels: 0, 1, 5, 10, 40, 70 and 100 ppm) were prepared. Sudan I imprinted polymers were synthesized by employing the interaction between Sudan I (template) and methacrylic acid (functional monomer), followed by washing to remove Sudan I leaving the Sudan I-binding sites exposed. MIPs were used as a stationary phase for TLC and could selectively retain Sudan I at the original spot with little interference. A gold colloid SERS substrate could enhance Raman intensity for Sudan I in this MIP-TLC system. Principal component analysis plot and partial least squares regression (R(2)=0.978) models were constructed and a linear regression model (R(2)=0.983) correlated spiking levels (5, 10, 40, 70 and 100 ppm) with the peak intensities (721 cm(-1)) of Sudan I SERS spectra. Both separation (30-40s) and detection (1s or 0.1s) were extremely fast by using both commercial bench-top and custom made portable Raman spectrometers. This biosensor can be applied as a rapid, low-cost and reliable tool for screening Sudan I adulteration in foods. PMID:26078169

  4. Representation of drought frequency in Southern South America performed by 14 CMIP5 models. Drought risk implications and perspectives towards future projections

    NASA Astrophysics Data System (ADS)

    Rivera, J. A.; Penalba, O. C.

    2012-12-01

    Drought frequency estimation is a key variable for drought risk assessment. The aim of this research is to evaluate how well the global climate models (GCMs) represent the drought frequencies in Southern South America (south of 20°S). For that purpose, we used the Standardized Precipitation Index (SPI), which quantifies the number of standard deviations that the accumulated rainfall in a given time scale deviates from the average value of a location in a particular period. The SPI is one of the drought indices most widely used worldwide, and one of the best suited for the study area. In order to build this index, monthly rainfall data were obtained from the CLARIS LPB Data Base for 120 of its stations, which were subjected to quality control procedures and have less than 10% of missing values. The SPI was computed for the period 1979-2008 on a time scale of 12 months, which represents long-term droughts. This procedure was also applied to the simulated precipitation from 14 CMIP5 GCMs over the study area. Two types of comparisons were performed, the first one for drought frequencies without taking into account the different drought classes and the second one for the frequencies of moderate, severe and extreme drought events. This second comparison is important given that drought risk was evaluated through a weighted index based in drought frequencies, which was constructed as a sum of drought classes -moderate, severe and extreme- with a weighting scheme. Most of the regions with moderate to high observed drought frequencies are located in the western and southern portions of La Plata Basin and over Patagonia region, while lower observed drought frequencies were obtained for Northern Argentina, Southern Brazil and Paraguay. This spatial pattern is barely reproduced by the modeled frequencies, and in some cases major differences exist. In order to analyze these differences, we performed a regional assessment of the SPI time series, which showed that the time series

  5. A lithofacies terrain model for the Blantyre Region: Implications for the interpretation of palaeosavanna depositional systems and for environmental geology and economic geology in southern Malawi

    NASA Astrophysics Data System (ADS)

    Dill, H. G.; Ludwig, R.-R.; Kathewera, A.; Mwenelupembe, J.

    2005-06-01

    The Blantyre City Area is part of the African savanna in southern Malawi. Sedimentological, geomorphological, chemical and mineralogical studies were conducted to create a lithofacies terrain model. The project involves mapping, cross-sectioning, grain size, heavy mineral analysis, XRD and the study of sedimentary textures under the petrographic microscope. These classical techniques were combined with GIS-based field and office works. The combined efforts led to 2-D maps and 3-D block diagrams that illustrate the geomorphological and sedimentological evolution of the landscape in southern Malawi during the late Mesozoic and Cenozoic. The results obtained through integrated geomorphological-sedimentological studies form the basis for land management (planning of residential areas, waste disposal sites, assessment of bearing capacity of rocks), geohazard prediction (delineation of high risk zones in terms of mass flow and inundation) and the evaluation of high-place (ceramic raw materials) and high-unit value (placers of precious metals and gemstones) mineral commodities in the study area. The study addresses regional and general aspects alike. In regional terms, the study aimed at unraveling the evolution of landforms at the southern end of the East African Rift System during the most recent parts of the geological past. Four stages of peneplanation were established in the working area. Planation was active from the Cretaceous to the Quaternary (stage I: early to mid-Cretaceous, stage II: early Tertiary, stage III: early to mid-Tertiary, stage IV: mid- to late Tertiary). During the most recent parts of the Quaternary, strong fluvial incision was triggered by the base-level lowering of the Shire River. Geomorphological alteration of the landscape goes along with a phyllosilicate-sesquioxide transformation from minerals indicative of more acidic meteoric fluids (e.g., gibbsite, kaolinite) to those typical of more alkaline conditions (e.g. smectite, vermiculite

  6. Surface exposure chronology of the Waimakariri glacial sequence in the Southern Alps of New Zealand: Implications for MIS-2 ice extent and LGM glacial mass balance

    NASA Astrophysics Data System (ADS)

    Rother, Henrik; Shulmeister, James; Fink, David; Alexander, David; Bell, David

    2015-11-01

    During the late Quaternary, the Southern Alps of New Zealand experienced multiple episodes of glaciation with large piedmont glaciers reaching the coastal plains in the west and expanding into the eastern alpine forelands. Here, we present a new 10Be exposure age chronology for a moraine sequence in the Waimakariri Valley (N-Canterbury), which has long been used as a reference record for correlating glacial events across New Zealand and the wider Southern Hemisphere. Our data indicate that the Waimakariri glacier reached its maximum last glaciation extent prior to ∼26 ka well before the global last glaciation maximum (LGM). This was followed by a gradual reduction in ice volume and the abandonment of the innermost LGM moraines at about 17.5 ka. Significantly, we find that during its maximum extent, the Waimakariri glacier overflowed the Avoca Plateau, previously believed to represent a mid-Pleistocene glacial surface (i.e. MIS 8). At the same time, the glacier extended to a position downstream of the Waimakariri Gorge, some 15 km beyond the previously mapped LGM ice limit. We use a simple steady-state mass balance model to test the sensitivity of past glacial accumulation to various climatic parameters, and to evaluate possible climate scenarios capable of generating the ice volume required to reach the full local-LGM extent. Model outcomes indicate that under New Zealand's oceanic setting, a cooling of 5 °C, assuming modern precipitation levels, or a cooling of 6.5 °C, assuming a one third reduction in precipitation, would suffice to drive the Waimakariri glacier to the eastern alpine forelands (Canterbury Plains). Our findings demonstrate that the scale of LGM glaciation in the Waimakariri Valley and adjacent major catchments, both in terms of ice volume and downvalley ice extent, has been significantly underestimated. Our observation that high-lying glacial surfaces, so far believed to represent much older glacial episodes, were glaciated during the LGM

  7. Tectonic geomorphology and paleoseismology of strike-slip faults in Jamaica: Implications for distribution of strain and seismic hazard along the southern edge of the Gonave microplate

    NASA Astrophysics Data System (ADS)

    Koehler, R. D.; Mann, P.; Brown, L. A.

    2009-12-01

    The east-west, left lateral strike-slip fault system forming the southern edge of the Gonave microplate crosses the110-km-long and 70-km-wide island of Jamaica. GPS measurements in the northeastern Caribbean are supportive of the microplate interpretation and indicate that ~ half of the Caribbean-North America left-lateral plate motion (8-14 mm/yr) is carried by the Plantain Garden (PGFZ) and associated faults in Jamaica. We performed Neotectonic mapping of the Plantain Garden fault along the southern rangefront of the Blue Mountains and conducted a paleoseismic study of the fault at Morant River. Between Holland Bay and Morant River, the fault is characterized by a steep, faceted, linear mountain front, prominent linear valleys and depressions, shutter ridges, and springs. At the eastern end of the island, the PGFZ is characterized by a left-stepping fault geometry that includes a major, active hot spring. The river cut exposure at Morant River exposes a 1.5-m-wide, sub-vertical fault zone juxtaposing sheared alluvium and faulted Cretaceous basement rocks. This section is overlain by an, unfaulted 3-m-thick fluvial terrace inset into a late Pleistocene terrace that is culturally modified. Upward fault terminations indicate the occurrence of three paleoearthquakes that occurred prior to deposition of the flat lying inset terrace around 341-628 cal yr BP. At this time, our radiocarbon results suggest that we can rule out the PGFZ as the source of the 1907 Kingston earthquake 102 years ago, as well as, the 1692 event that destroyed Port Royal 317 years ago and produced a major landslide at Yallahs. Pending OSL ages will constrain the age of the penultimate and most recent ruptures. Gently to steeply dipping rocks as young as Pliocene exposed in roadcuts within the low coastal hills south of and parallel to the Plantain Garden fault may indicate active folding and blind thrust faulting. These structures are poorly characterized and may accommodate an unknown amount of

  8. Geochronology and geochemistry of late Paleozoic magmatic rocks in the Yinwaxia area, Beishan: Implications for rift magmatism in the southern Central Asian Orogenic Belt

    NASA Astrophysics Data System (ADS)

    Zheng, Rongguo; Wu, Tairan; Zhang, Wen; Meng, Qingpeng; Zhang, Zhaoyu

    2014-09-01

    Mafic-ultramafic rocks are distributed widely in the Beishan rift, which is located in the southern Beishan, central southern Central Asian Orogenic Belt. The Yinwaxia study area is located in eastern Beishan rift, where mafic-ultramafic rocks occur along major faults. The zircon SHRIMP U-Pb age obtained of a gabbro is 281 ± 11 Ma, and the age of the basalt is constrained by the youngest xenocrystal with an age of 265 Ma, which substantiate that these mafic rocks formed in Permian. Basalts and gabbros exhibit similar geochemical characteristics including: high SiO2, total Fe2O3 and TiO2 contents; low MgO contents and Mg# values; and tholeiitic characteristics. Yinwaxia mafic rocks have relatively high total rare earth element contents, enrichment in light rare earth elements, enrichments in the high field strength elements, and obvious negative Nb-Ta-Ti anomalies. Basalts exhibit low (87Sr/86Sr)i and high εNd(t) values, while gabbros exhibit relatively high (87Sr/86Sr)i and low εNd(t) values. Isotopic compositions of these mafic rocks display a mixed trend between depleted and enriched mantles. Meanwhile, differing εNd(t) values show that basalts were intensively contaminated by juvenile crustal materials, but gabbros were contaminated by older continental crust. We conclude that Yinwaxia mafic rocks were derived from lithospheric mantle metasomatized by fluids and/or melts from subducted slab; parental magmas underwent AFC processes, then emplaced along faults in a continental rift. We collected geochemical and geochronological data in the study area, and collated geochronological data from previous workers in the Beishan orogenic belt to develop a geochronological frequency diagram. From these data and analyses we deduced a model of tectonic evolution for the Beishan orogenic belt. Considering the geochemistry, sedimentological evidence for rifting, and the geochronological frequency diagram, we propose that the Beishan rift had entered a post-collision stage

  9. Habitat overlap between southern bluefin tuna and yellowfin tuna in the east coast longline fishery - implications for present and future spatial management

    NASA Astrophysics Data System (ADS)

    Hartog, Jason R.; Hobday, Alistair J.; Matear, Richard; Feng, Ming

    2011-03-01

    Southern bluefin tuna (SBT) are presently a quota-managed species in the multi-species eastern Australian tuna and billfish longline fishery (ETBF). Capture of SBT is regulated by quota, as is access to regions likely to contain SBT. A habitat prediction model combining data from an ocean model and pop-up satellite archival tags is used to define habitat zones based on the probability of SBT occurrence. These habitat zones are used by fishery managers to restrict access by ETBF fishers to SBT habitat during a May-November management season. The zones display a distinct seasonal cycle driven by the seasonal southward expansion and northward contraction of the East Australia Current (EAC) and as a result access by fishers to particular ocean regions changes seasonally. This species also overlaps with the commercially valuable yellowfin tuna (YFT), thus, we modified the SBT model to generate YFT habitat predictions in order to investigate habitat overlap between SBT and YFT. There is seasonal variation in the overlap of the core habitat between these two species, with overlap early (May-Jul) in the management season and habitat separation occurring towards the end (Aug-Nov). The EAC is one of the fastest warming ocean regions in the southern hemisphere. To consider the future change in distribution of these two species compared to the present and to explore the potential impact on fishers and managers of the future, we use future ocean predictions from the CSIRO Bluelink ocean model for the year 2064 to generate habitat predictions. As the ocean warms on the east coast of Australia and the EAC extends southward, our model predicts the suitable habitat for SBT and YFT will move further south. There was an increase in the overlap of SBT and YFT habitat throughout the management season, due to regional variation of each species' habitat. These results illustrate that a management tradeoff exists between restricting fisher access to SBT habitat and allowing access to YFT

  10. Early evolution of the southern margin of the Neuquén Basin, Argentina: Tectono-stratigraphic implications for rift evolution and exploration of hydrocarbon plays

    NASA Astrophysics Data System (ADS)

    D'Elia, Leandro; Bilmes, Andrés; Franzese, Juan R.; Veiga, Gonzalo D.; Hernández, Mariano; Muravchik, Martín

    2015-12-01

    Long-lived rift basins are characterized by a complex structural and tectonic evolution. They present significant lateral and vertical stratigraphic variations that determine diverse basin-patterns at different timing, scale and location. These issues cause difficulties to establish facies models, correlations and stratal stacking patterns of the fault-related stratigraphy, specially when exploration of hydrocarbon plays proceeds on the subsurface of a basin. The present case study corresponds to the rift-successions of the Neuquén Basin. This basin formed in response to continental extension that took place at the western margin of Gondwana during the Late Triassic-Early Jurassic. A tectono-stratigraphic analysis of the initial successions of the southern part of the Neuquén Basin was carried out. Three syn-rift sequences were determined. These syn-rift sequences were located in different extensional depocentres during the rifting phases. The specific periods of rifting show distinctly different structural and stratigraphic styles: from non-volcanic to volcanic successions and/or from continental to marine sedimentation. The results were compared with surface and subsurface interpretations performed for other depocentres of the basin, devising an integrated rifting scheme for the whole basin. The more accepted tectono-stratigraphic scheme that assumes the deposits of the first marine transgression (Cuyo Cycle) as indicative of the onset of a post-rift phase is reconsidered. In the southern part of the basin, the marine deposits (lower Cuyo Cycle) were integrated into the syn-rift phase, implying the existence of different tectonic signatures for Cuyo Cycle along the basin. The rift climax becomes younger from north to south along the basin. The post-rift initiation followed the diachronic ending of the main syn-rift phase throughout the Neuquén Basin. Thus, initiation of the post-rift stage started in the north and proceeded towards the south, constituting a

  11. Elemental and Sr Nd isotopic systematics of the early Mesozoic volcanic sequence in southern Jiangxi Province, South China: petrogenesis and tectonic implications

    NASA Astrophysics Data System (ADS)

    Wang, Yuejun; Fan, Weiming; Peng, Touping; Guo, Feng

    2005-02-01

    Elemental and Sr Nd isotopic results are presented for the early Mesozoic volcanic sequence (~172 Ma) in southern Jiangxi Province, South China. The sequence is voluminously composed of ~45% subalkaline basaltic rocks (group 1), <5% high-mg andesite dacites (group 2) and ~50% rhyolites (group 3). The group 1 rocks are characterized by (La/Yb)cn = 3.8 7.2, Eu/Eu* = 0.65 1.15, Nb/La = 0.64 0.99, 87Sr/86Sr(t) = 0.70602~0.70822 and ɛNd(t) = -1.63 to +0.11, similar to those of an EMII-like source. The group 2 rocks have mg=0.42~0.60, SiO2=60.24~66.71%, MgO=2.65~ 5.54%, Ni=24~102 ppm and Cr=84~266 ppm, classified as high-mg andesitic rocks. These rocks are more enriched in LILEs and LREE with more significant negative Eu anomaly (0.63~0.79), are more depleted in HFSEs with Nb/La ratios of 0.40 0.56 and have lower ɛNd(t) (-9.44 to -7.78) and higher 87Sr/86Sr(t) (0.70985~0.71016), in comparison with the group 1 rocks. They most likely originated from metasomatised veins in the lithospheric mantle. The origination of the group 1 and group 2 magma suggests the development of a peridotite-plus-vein lithospheric mantle during early Mesozoic era beneath the interior of the Cathaysian block. The group 3 rhyolites are characterized by high SiO2 (72.75~77.97%), Zr (99~290 ppm), Hf (3.9~9.7 ppm) and Ga/Al (2.76~3.87) and significant Nb Ta, Ba Sr and P Ti depletions. These rhyolites exhibit Sr Nd isotopic compositions (87Sr/86Sr(t) = 0.70962~0.71104, ɛNd(t) = -4.63 to -5.80) similar to the contemporaneous Zhaibei and Pitou A-type granites in the area. Such characteristics suggest that they might be derived from the underplating basaltic magma contaminated by crustal materials. Therefore, an early Mesozoic rifting model in response to intracontinental lithospheric extension is proposed to account for the early Mesozoic volcanism in southern Jiangxi Province, South China.

  12. Early Cretaceous low-Mg# adakitic rocks in the southern margin of the central North China Craton: Partial melting of thickened lower continental crust and tectonic implications

    NASA Astrophysics Data System (ADS)

    Yang, D.

    2015-12-01

    This paper reports new whole-rock geochemical, Sr-Nd-Pb isotopic, and zircon U-Pb and Hf isotopic data for Early Cretaceous intrusive rocks in the Sanmenxia-Houma area of central China, and uses these data to constrain the petrogenesis of low-Mg adakitic rocks (LMAR) and the spatial extent of the influence of the deeply subducted Yangtze slab during the Triassic evolution of this region. New zircon LA-ICP-MS U-Pb data indicate that the early- and late-stage southern Quli, Qiligou, and Gaomiao porphyritic quartz diorites, the Canfang granodiorite, and the northern Wangmao porphyritic quartz monzodiorite were emplaced during the Early Cretaceous (~130 Ma) and the late Early Cretaceous (116 Ma). These rocks are characterized by high Na2O/K2O, Sr/Y, and (La/Yb)n ratios as well as high Sr concentrations, low Mg# values, and low heavy rare earth element and Y concentrations, all of which indicate an LMAR affinity. The samples have relatively high initial 87Sr/86Sr ratios (0.7054-0.7095), and low eNd(t) (-11.90 to -22.20) and eHf(t) (-16.7 to -32.7) values, indicative of a lower continental crust origin. The presence of Neoproterozoic (754-542 Ma) and inherited Late Triassic (220 Ma) metamorphic zircons within the late Early Cretaceous LMAR and the relatively high 206Pb/204Pb ratios of these rocks suggest that they formed from primary magmas derived from partial melting of Yangtze Craton (YC) basement material that had undergone ultrahigh-pressure metamorphism. In contrast, the presence of Paleoproterozoic and Archean inherited zircons within early Early Cretaceous LMAR in this area and the relatively low 206Pb/204Pb ratios of these rocks are indicative of derivation from primary magmas generated by partial melting of the thickened lower continental crust of the North China Craton (NCC). These rocks may have formed in an extensional environment associated with the upwelling of asthenospheric mantle material. The presence of YC basement material within the NCC in the

  13. Evolution of the late Quaternary San Gregorio Magno tectono-karstic basin (southern Italy) inferred from geomorphological, tephrostratigraphical and palaeoecological analyses: tectonic implications

    NASA Astrophysics Data System (ADS)

    Aiello, G.; Ascione, A.; Barra, D.; Munno, R.; Petrosino, P.; Russo Ermolli, E.; Villani, F.

    2007-03-01

    The Pantano di San Gregorio Magno is a 4.7 km2 large tectono-karstic basin located in the axial belt of the Southern Apennines, an area affected by intense seismicity. The basin was formed in the Middle Pleistocene and is presently undissected. It is filled by lacustrine sediments (clays, silts and pyroclastic sands) passing laterally into alluvial fan deposits. Geomorphological investigations were integrated with tephrostratigraphical, palynological and palaeoecological analyses of a 61 m thick core (not reaching the bedrock). The multiproxy analysis of the S. Gregorio Magno record shows that, over the last 200k yr, the basin hosted a freshwater lake with an oscillating level. Age constraints provided by the tephrostratigraphic record allowed estimation of the sedimentation rate, which varied strongly through time. Evolution of the basin resulted from the complex combination of tectonic subsidence, karst processes and changing amounts of sedimentary inputs. The latter was influenced by allogenic contributions related both to primary and reworked volcanoclastic inputs and was climate-driven. The overall evidence, which indicates that in the long-term the accumulation rate substantially counterbalanced the accommodation space created by faulting, suggests that the basin evolution was also modulated by changing subsidence rates. Copyright

  14. The AyiaTriadha Cave, Southern Euboea Finds and Implications of the Earliest Human Habitation in the Area (A Preliminary Report).

    NASA Astrophysics Data System (ADS)

    Mavridis, F.; Tankosić, Ž.

    The Ayia Triadha cave excavation project aims to explore early maritime connections in the Aegean during the Late Neolithic I and II and the Early Bronze Age. The cave lies in a strategic position close to the crossroads that connect insular regions and the mainland. We also aim to explore the manifestations of the so-called Saliagos culture of the Cyclades and the Aegean. This culture is connected to the White-on-Dark pottery horizon (late sixth to early fifth millennium B.C.) found in the cave. The Final Neolithic/LNIIa material is also present in the cave in large quantities. It is closely connected to the Attica-Kephala horizon (late fifth/fourth millennium B.C.) known from the Cyclades and the southern part of mainland Greece. Of great importance is the identification of an Early Bronze Age context, located inside a small chamber, off the main entrance corridor. In this paper we present our preliminary results from the 2007 field season and some aspects of the 2008 campaign together with research strategies we plan to apply in the future.

  15. P-T-t deformation framework of an accretionary prism, southern New England Orogen, eastern Australia: Implications for blueschist exhumation and metamorphic switching

    NASA Astrophysics Data System (ADS)

    Phillips, G.; Hand, M.; Offler, R.

    2008-12-01

    The Tia Complex is located in the southern New England Orogen of eastern Australia and provides a detailed record of the structural-metamorphic evolution of an ancient accretionary prism. This record is characterized by six stages of deformation that were accompanied by a transition from moderate-pressure-low-temperature to low-pressure-high-temperature metamorphism. The composition of jadeitic pyroxene (subduction), magnesioriebeckite (exhumation), and actinolite (heating) have been used to model P-T conditions during these structural events, which range from P = 6.3-6.7 kbar and T = 320-350°C (subduction) to 1.5-2.0 kbar and 400-420°C (heating). On the basis of new structural and metamorphic data combined with preexisting age data, the evolution of this accretionary prism can be divided into two main stages: (1) blueschist formation and exhumation and (2) elevated heat flow and anatexis. To explain these features, a new model is presented that requires (1) wedge underthrusting and rear wedge extension associated with a stationary subduction hinge and (2) subduction hinge migration resulting in the relocation of the accretionary wedge onto the upper plate and heating during exposure to the mantle wedge. To explain the event chronology preserved in the Tia Complex, both extensional collapse and subduction hinge migration models are required.

  16. Miocene tectono-stratigraphic history of La Mision basin, northwestern Baja California: implications for early tectonic development of southern California continental borderland

    SciTech Connect

    Ashby, J.R.; Minch, J.

    1988-03-01

    The middle Miocene La Mision basin in northwestern Baja California, Mexico, provides a rare opportunity to study an onshore portion of the southern California continental borderland. Stratigraphy, geometry of dispersal, and a variety of lithotypes within the volcanic and volcaniclastic sediments of the Rosarito Beach Formation provide clues to the nature of early tectonic evolution of this area during the Miocene. The elongated, trough-shaped La Mision basin formed in response to peninsular basement uplifts and the formation of volcanic highlands west of the present coastline. Lithologies and depositional environments represented within the basin sediments include: subaerial basalt flows and airfall tuffs, submarine muddy- and sandy-matrix mudflow breccias, lapilli tuffs, crystal tuffs, tuffaceous sandstones,d diatomites, and conglomerates. The environments of deposition range from fluvatile to intertidal to shallow marine. Early basin infilling is characterized by sediments and basalts, with a western source terrane, that were deposited against the faulted seacliffs. progressive infilling against the seacliff resulted in the formation of an extensive eastward-sloping basaltic platform extending eastward to the foothill coastal belt of the Peninsular Ranges. Marine transgression and subsequent regression are recorded by diverse marine volcaniclastic lithologies. Abundant fossils, K-Ar dates, and paleomagnetic data obtained from the La Mision basin allow precise correlation with other areas in the continental borderland and provide conclusive evidence that this block of the borderland was formed and in its present position by 16-14 Ma.

  17. Implications of carbon isotope ratios of C27-C33 alkanes and C37 alkenes for the sources of organic matter in the southern ocean surface sediments

    NASA Astrophysics Data System (ADS)

    Ohkouchi, N.; Kawamura, K.; Takemoto, N.; Ikehara, M.; Nakatsuka, T.

    2000-01-01

    Carbon isotopic ratios (δ13C) of C27-C33 n-alkanes and C37 alkenes were measured in the surface sediments from Australian sector of Southern Ocean (47.6°-65.5°S). The δ13C of C31 n-alkane derived from higher plant wax shows little change along the latitude (-28.7±0.6 ‰), whereas δ13C of C37 alkenes derived from haptophyte algae decreases from -24.6±0.7 ‰ at 47.6°S to -32.1±1.2 ‰ at 63.9°S. Relatively heavy δ13C values of C31 n-alkane suggest significant contribution of C4 plant waxes or conifer resin whose δ13C of n-alkanes are significantly heavier than those of C3 plants. The δ13C of total organic carbon exhibits a latitudinal pattern similar to that of C37 alkenes, suggesting that organic carbon in the sediments is primarily of marine origin.

  18. Low-grade metamorphism in the eastern Southern Alps: Distribution, conditions, timing and implications for the tectonics of the Alps and NW Dinarides

    NASA Astrophysics Data System (ADS)

    Neubauer, Franz; Heberer, Bianca; Genser, Johann; Friedl, Getrude

    2014-05-01

    Based on 40Ar/39Ar dating of newly-grown syntectonic metamorphic white mica (sericite), we recognize for the first time the timing of Alpine low-grade metamorphism in the eastern part of the Southalpine unit: (1) A Silurian phyllite of Seeberg inlier located to the south of the Periadriatic fault yields a plateau age at c. 75 Ma suggesting a Late Cretaceous age of previously recognized low-grade (Rantitsch & Rainer, 2003) metamorphism. (2) Within the Tolmin nappe, four sericite plateau ages of mainly Middle Triassic volcanics are at c. 51 Ma (Early Eocene). The Late Cretaceous age in the Seeberg inlier is considered to record ductile deformation during formation of a retro-wedge related to the Eo-Alpine orogeny in the Austroalpine units in the Eastern Alps exposed north of the future Periadriatic fault. The Eocene age at the boundary of very low-grade to low-grade metamorphism in the Tolmin nappe (Rainer et al., 2009) relates to the emplacement of the Southalpine nappe complex onto the Dinarides and is contemporaneous with the initial ductile deformation in the Dinarides during Adria-directed shortening and formation of a siliciclastic flysch belt in front of the SW-directed growing fold-thrust belt (Placer, 2008). Similar rare Late Cretaceous and dominant Eocene ages within post-Variscan units are virtually more widespread in the Southalpine unit and Dinarides as considered before. These regions include the Collio basin (Feijth, 2002) and the Eder unit (Läufer et al., 1996) in the western and central Southern Alps, in the internal NW Dinarides (Borojević Šoštarić et al., 2012) and the Mid Bosnian Schist Mountains (Pamić et al., 2004) and Lim Paleozoic unit in the central Dinarides (Ilic et al., submitted). Consequently, the Southalpine unit and Dinarides were affected by two stages of metamorphism, Late Cretaceous (ca. 80 to 75 Ma) and Eocene (ca. 51 - 40 Ma), both stages are related to back-thrusting. The ages of metamorphism are different from those in the

  19. The influence of climatic conditions on long-term changes in the helminth fauna of terrestrial molluscs and the implications for parasite transmission in southern England.

    PubMed

    Morley, N J; Lewis, J W

    2008-12-01

    The influence of climatic conditions on the prevalence and transmission of helminth parasites in a terrestrial mollusc population was studied in a grassland site in southern England between 1974 and 1983. Molluscs were sampled in each September of 5 years over this period (1974, 1976, 1979, 1981, 1983). Climatic conditions had a variable effect on parasite prevalence. Trematode sporocyst infections increased after wet summer and warm winter conditions and declined in hot, dry periods. Cestode infections increased after combined wet spring and summer weather and low winter temperatures, although trematode metacercariae and nematode infections were less likely to be influenced by climate. The effects on parasite transmission were undertaken by comparing parasite prevalences in the principal definitive hosts, the common shrew (Sorex araneus) and the wood mouse (Apodemus sylvaticus) in the same habitat over the period 1973-1983. Changes in parasite prevalences in the molluscan population were rarely replicated by changes in the small mammal population, except for trematode parasites in small mammals during a period of severe drought in 1976. These results suggest that only long-term persistent modifications in climate are likely to affect host-parasite dynamics.

  20. Abrupt turnover in calcareous-nannoplankton assemblages across the Paleocene/Eocene Thermal Maximum: implications for surface-water oligotrophy over the Kerguelen Plateau, Southern Indian Ocean

    USGS Publications Warehouse

    Jiang, Shijun; Wise, Sherwood W.

    2007-01-01

    Ocean Drilling Program (ODP) Core Section 183-1135A-25R-4 from the Kerguelen Plateau in the Indian Ocean sector of the Southern Ocean represents only the second complete, expanded sequence through the Paleocene/Eocene Thermal Maximum (PETM; ~55 Ma) recovered from Antarctic waters. Calcareous nannoplankton at this site underwent an abrupt, fundamental turnover across the PETM as defined by a carbon isotope excursion. Although Chiasmolithus, Discoaster, and Fasciculithus exponentially increase in abundance at the onset, the former abruptly drops but then rapidly recovers, whereas the latter two taxa show opposite trends due to surface-water oligotrophy. These observations confirm previous results from ODP Site 690 on Maud Rise. The elevated pCO2 that accompanied the PETM caused a shoaling of the lysocline and carbonate compensation depth, leading to intensive dissolution of susceptible holococcoliths and poor preservation of the assemblages. Similarities and contrasts between the results of this study and previous work from open-ocean sites and shelf margins further demonstrate that the response to the PETM was consistent in open-ocean environments, but could be localized on continental shelves where nutrient regimes depend on the local geologic setting and oceanographic conditions.

  1. Factors affecting competitive dominance of rainbow trout over brook trout in southern Appalachian streams: Implications of an individual-based model

    SciTech Connect

    Clark, M.E.; Rose, K.A.

    1997-01-01

    We used an individual-based model to examine possible explanations for the dominance of rainbow trout Oncorhynchus mykiss over brook trout Salvelinus fontinalis in southern Appalachian streams. Model simulations were used to quantify the effects on interspecific competition of (1) competitive advantage for feeding sites by rainbow trout, (2) latitudinal differences in stream temperatures, flows, and daylight, (3) year-class failures, (4) lower fecundity of brook trout, and (5) reductions in spawning habitat. The model tracks the daily spawning, growth, and survival of individuals of both species throughout their lifetime in a series of connected stream habitat units (pools, runs, or riffles). Average densities of each species based on 100-year simulations were compared for several levels of each of the five factors and for sympatric and allopatric conditions. Based on model results and empirical information, we conclude that more frequent year-class failures and the lower fecundity of brook trout are both possible and likely explanations for rainbow trout dominance, that warmer temperatures due to latitude and limited spawning habitat are possible but unlikely explanations, and that competitive advantage for feeding sites by rainbow trout is an unlikely explanation. Additional field work should focus on comparative studies of the reproductive success and the early life stage mortalities of brook and rainbow trout among Appalachian streams with varying rainbow trout dominance. 53 refs., 11 figs.

  2. Geomorphic assessment of late Quaternary volcanism in the Yucca Mountain area, southern Nevada: Implications for the proposed high-level radioactive waste repository

    SciTech Connect

    Wells, S.G.; McFadden, L.D.; Renault, C.E.; Crowe, B.M.

    1991-03-01

    Volcanic hazard studies for high-level radioactive waste isolation in the Yucca Mountain area, Nevada, require a detailed understanding of Quaternary volcanism to forecast rates of volcanic processes. Recent studies of the Quaternary Cima volcanic fields in southern California have demonstrated that K-Ar dates of volcanic landforms are consistent with their geomorphic and pedologic properties. The systematic change of these properties with time may be used to provide age estimates of undated or questionably dated volcanic features. The reliability of radiometric age determinations of the youngest volcanic center, Lathrop Wells, near the proposed Yucca Mountain site in Nevada has been problematic. In this study, a comparison of morphometric, pedogenic, and stratigraphic data establishes that correlation of geomorphic and soil properties between the Cima volcanic field and the Yucca Mountain area is valid. Comparison of the Lathrop Wells cinder cone to a 15-20 ka cinder cone in California shows that their geomorphic-pedogenic properties are similar and implies that the two cones are of similar age. The authors of ca. 0.27 Ma for the latest volcanic activity at Lathrop Wells, approximately 20 km from the proposed repository, may be in error by as much as an order of magnitude and that the most recent volcanic activity is no older than 20 ka.

  3. Geomorphic assessment of late Quarternary volcanism in the Yucca Mountain area, southern Nevada: Implication for the proposed high-level radiocative waste repository

    SciTech Connect

    Wells, S.G.; McFadden, L.D.; Renault, C.E.; Crowe, B.M.

    1990-06-01

    Volcanic hazard studies for high-level radioactive waste isolation in the Yucca Mountain area, Nevada, require a detailed understanding of Quaternary volcanism to forecast rates of volcanic processes. Recent studies of the Quaternary Cima volcanic field in southern California have demonstrated that K-Ar dates of volcanic landforms are consistent with their geomorphic and pedologic properties. The systematic change of these properties with time may be used to provide age estimates of undated or questionably dated volcanic features. The reliability of radiometric age determinations of the youngest volcanic center, Lathrop Wells, near the proposed Yucca Mountain site in Nevada has been problematic. In this study, a comparison of morphometric, pedogenic, and stratigraphic data establishes that correlation of geomorphic and soil properties between the Cima volcanic field and the Yucca Mountain area is valid. Comparison of the Lathrop Wells cinder cone to a 15-20 ka cinder cone in California shows that their geomorphic-pedogenic properties are similar and implies that the two cones are of similar age. We conclude that previous determinations of ca. 0.27 Ma for the latest volcanic activity at Lathrop Wells, approximately 20 km from the proposed repository, may be in error by as much as an order of magnitude and that the most recent volcanic activity is no older than 20ka.

  4. Isotopic composition of a calcite-cemented layer in the Lower Jurassic Bridport Sands, southern England: Implications for formation of laterally extensive calcite-cemented layers

    SciTech Connect

    Bjoerkum, P.A. ); Walderhaug, O. )

    1993-07-01

    [delta][sup 18]O[sub PDB] and [delta][sup 13]C[sub PDB] values have been measured on 107 calcite cement samples from a laterally extensive (> 3 km) and continuous calcite-cemented layer 0.5 m thick in the coastal exposures of the Lower Jurassic shallow-marine Bridport Sands in Dorset, southern England. The samples were taken from a two-dimensional grid with 10-cm horizontal and vertical spacing between samples and along individual vertical lines across the calcite-cemented layer, [delta][sup 18]O[sub PDB] values vary between [minus]4.8% and [minus]9.2% and decrease radially outwards from points with lateral spacings on the order of 0.5-1 m in the middle of the calcite-cemented layer. The [delta][sup 18]O[sub PDB] values therefore indicate that the calcite-cemented layer was formed by merging of concretions. All [delta][sup 13]C[sub PDB] values measured are in the narrow range [minus]2.2% to [minus]0.5%, which suggests that the dominant source of calcite cement in the layer was biogenic carbonate.

  5. Geographic distribution of Theileria sp. (buffalo) and Theileria sp. (bougasvlei) in Cape buffalo (Syncerus caffer) in southern Africa: implications for speciation.

    PubMed

    Pienaar, Ronel; Latif, Abdalla A; Thekisoe, Oriel M M; Mans, Ben J

    2014-03-01

    Strict control measures apply to movement of buffalo in South Africa including testing for Theileria parva, the causative agent of Corridor disease in cattle. The official test is a real-time hybridization PCR assay that amplifies the 18S rRNA V4 hyper-variable region of T. parva, T. sp. (buffalo) and T. sp. (bougasvlei). Mixed infections with the latter organisms affect diagnostic sensitivity due to PCR suppression. While the incidence of mixed infections in the Corridor disease endemic region of South Africa is significant, little information is available on the specific distribution and prevalence of T. sp. (buffalo) and T. sp. (bougasvlei). Specific real-time PCR assays were developed and a total of 1211 samples known to harbour these parasites were screened. Both parasites are widely distributed in southern Africa and the incidence of mixed infections with T. parva within the endemic region is similar (∼25-50%). However, a significant discrepancy exists in regard to mixed infections of T. sp. (buffalo) and T. sp. (bougasvlei) (∼10%). Evidence for speciation between T. sp. (buffalo) and T. sp. (bougasvlei) is supported by phylogenetic analysis of the COI gene, and their designation as different species. This suggests mutual exclusion of parasites and the possibility of hybrid sterility in cases of mixed infections.

  6. Regional variations in upper mantle compressional velocities beneath southern California 1. Post-shock temperatures: Their experimental determination, calculation, and implications, 2.. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Raikes, S. A.

    1978-01-01

    The compressional velocity within the upper mantle beneath Southern California is investigated through observations of the dependence of teleseismic P-delays at all stations of the array on the distance and azimuth to the event. The variation of residuals with azimuth was found to be as large as 1.3 sec at a single station; the delays were stable as a function of time, and no evidence was found for temporal velocity variations related to seismic activity in the area. These delays were used in the construction of models for the upper mantle P-velocity structure to depths of 150 km, both by ray tracing and inversion techniques. The models exhibit considerable lateral heterogeneity including a region of low velocity beneath the Imperial Valley, and regions of increased velocity beneath the Sierra Nevada and much of the Transverse Ranges. The development is described of a technique for the experimental determination of post-shock temperatures, and its application to several metals and silicates shocked to pressures in the range 5 to 30 GPa. The technique utilizes an infra-red radiation detector to determine the brightness temperature of the free surface of the sample after the shock wave has passed through it.

  7. Geomorphic assessment of late Quaternary volcanism in the Yucca Mountain area, southern Nevada: Implications for the proposed high-level radioactive waste repository

    NASA Astrophysics Data System (ADS)

    Wells, S. G.; McFadden, L. D.; Renault, C. E.; Crowe, B. M.

    1990-06-01

    Volcanic hazard studies for high-level radioactive waste isolation in the Yucca Mountain area, Nevada, require a detailed understanding of Quaternary volcanism to forecast rates of volcanic processes. Recent studies of the Quaternary Cima volcanic field in southern California have demonstrated that K-Ar dates of volcanic landforms are consistent with their geomorphic and pedologic properties. The systematic change of these properties with time may be used to provide age estimates of undated or questionably dated volcanic features. The reliability off radiometric age determinations of the youngest volcanic center, Lathrop Wells, near the proposed Yucca Mountain site in Nevada has been problematic. In this study, a comparison of morphometric, pedogenic, and stratigraphic data establishes that correlation of geomorphic and soil properties between the Cima volcanic field and the Yucca Mountain area is valid. Comparison of the Lathrop Wells cinder cone to a 15-20 ka cinder cone in California shows that their geomorphic-pedogenic properties are similar and implies that the two cones are of similar age. We conclude that previous determinations of ca. 0.27 Ma for the latest volcanic activity at Lathrop Wells, approximately 20 km from the proposed repository, may be in error by as much as an order of magnitude and that the most recent volcanic activity is no older than 20 ka.

  8. Implications and concerns of deep-seated disposal of hydrocarbon exploration produced water using three-dimensional contaminant transport model in Bhit Area, Dadu District of Southern Pakistan.

    PubMed

    Ahmad, Zulfiqar; Akhter, Gulraiz; Ashraf, Arshad; Fryar, Alan

    2010-11-01

    A three-dimensional contaminant transport model has been developed to simulate and monitor the migration of disposal of hydrocarbon exploration produced water in Injection well at 2,100 m depth in the Upper Cretaceous Pab sandstone, Bhit area in Dadu district of Southern Pakistan. The regional stratigraphic and structural geological framework of the area, landform characteristics, meteorological parameters, and hydrogeological milieu have been used in the model to generate the initial simulation of steady-state flow condition in the underlying aquifer's layers. The geometry of the shallow and deep-seated characteristics of the geological formations was obtained from the drilling data, electrical resistivity sounding surveys, and geophysical well-logging information. The modeling process comprised of steady-state simulation and transient simulation of the prolific groundwater system of contamination transport after 1, 10, 30 years of injection. The contaminant transport was evaluated from the bottom of the injection well, and its short- and long-term effects were determined on aquifer system lying in varying hydrogeological and geological conditions.

  9. Implications and concerns of deep-seated disposal of hydrocarbon exploration produced water using three-dimensional contaminant transport model in Bhit Area, Dadu District of Southern Pakistan.

    PubMed

    Ahmad, Zulfiqar; Akhter, Gulraiz; Ashraf, Arshad; Fryar, Alan

    2010-11-01

    A three-dimensional contaminant transport model has been developed to simulate and monitor the migration of disposal of hydrocarbon exploration produced water in Injection well at 2,100 m depth in the Upper Cretaceous Pab sandstone, Bhit area in Dadu district of Southern Pakistan. The regional stratigraphic and structural geological framework of the area, landform characteristics, meteorological parameters, and hydrogeological milieu have been used in the model to generate the initial simulation of steady-state flow condition in the underlying aquifer's layers. The geometry of the shallow and deep-seated characteristics of the geological formations was obtained from the drilling data, electrical resistivity sounding surveys, and geophysical well-logging information. The modeling process comprised of steady-state simulation and transient simulation of the prolific groundwater system of contamination transport after 1, 10, 30 years of injection. The contaminant transport was evaluated from the bottom of the injection well, and its short- and long-term effects were determined on aquifer system lying in varying hydrogeological and geological conditions. PMID:19936954

  10. Contrasting styles of mineralization in the Chinese Altai and East Junggar, NW China: implications for the accretionary history of the southern Altaids

    NASA Astrophysics Data System (ADS)

    Wan, Bo; Xiao, Wenjiao; Windley, Brian

    2013-04-01

    The Chinese Altai-East Junggar collage in the southern Altaids hosts three metallogenic belts, which are, from north to south: (1) a volcanogenic massive sulphide (VMS) Cu-Pb-Zn belt; (2) a belt of shear zone-related gold deposits; (3) a porphyry Cu-Au-Mo belt. The VMS deposits formed in two pulses (c. 405 Ma and c. 375 Ma) in the Chinese Altai arc. The porphyry deposits developed in three pulses in the East Junggar arc, the first two synchronous with the VMS mineralization, and the third at c. 330 Ma. The shear zone-related gold deposits developed in the late Carboniferous to Permian at the contact between the Chinese Altai and East Junggar arcs. Time-space distributions of diverse ore deposits across the Altai-East Junggar collage indicate that the collage developed from two independent arcs, the Chinese Altai and the East Junggar. The VMS and porphyry deposits developed in the Chinese Altai and East Junggar arcs, respectively. The Chinese Altai arc is interpreted to be a Japanese-type arc, and the East Junggar arc a Mariana-type arc. During the latest Palaeozoic, the two arcs were juxtaposed by the Erqis Fault, when many shear zone-related lode gold deposits were emplaced. These metallogenic distributions were a likely response to spatially localized mechanisms of crust growth and to the tectonic evolution of the Altai-East Junggar collage, and they are consistent with interpretation of the Altaids as a multiple subduction-accretion collage.

  11. Risk maps for the presence and absence of Phlebotomus perniciosus in an endemic area of leishmaniasis in southern Spain: implications for the control of the disease.

    PubMed

    Barón, S D; Morillas-Márquez, F; Morales-Yuste, M; Díaz-Sáez, V; Irigaray, C; Martín-Sánchez, J

    2011-09-01

    The aim of this study was to construct risk maps for the presence of the dominant Leishmania infantum vector, P. perniciosus, and check its usefulness (a) to predict the risk of canine leishmaniasis and (b) to define effective leishmaniasis control measures. We obtained data for the presence/absence of P. perniciosus at 167 sampling sites in southern Spain, from which we also took a series of ecological and climate-related data. The probability of P. perniciosus presence was estimated as a function of these environmental variables and generated spatial risk maps. Altitude, land use and drainage hole features (with or without PVC piping) were retained as the only predictors for the distribution of this vector species. Drainage hole features in retaining walls, with or without PVC piping, produce significant variations in the probability of P. perniciosus presence, varying from 2·3 to 91·8% if PVC piping is absent and from 0·4 to 66·5% if all holes have PVC piping. It was concluded that the use of PVC piping in drainage holes could help to reduce leishmaniasis transmission. PMID:21854702

  12. Amperometric detection of Sudan I in red chili powder samples using Ag nanoparticles decorated graphene oxide modified glassy carbon electrode.

    PubMed

    Prabakaran, E; Pandian, K

    2015-01-01

    A simple and sensitive electrochemical method was developed to determine the concentration of Sudan I in chili powder based on silver nanoparticles decorated graphene oxide modified glassy carbon electrode (AgNPs@GO/GCE). The voltammetry behaviour of Sudan I on modified GCE was investigated in phosphate buffer medium (PBS) with various pH ranges and the electron transfer properties were studied. It is found that the AgNPs@GO/GCE can catalyse the reduction of azo group, -N=N- followed by electrochemical oxidation of (-)OH group present in Sudan I dye molecule. Quantitative detection of Sudan I present in food products was carried out by amperometry method in which reduction potential was fixed at -0.77 V vs. Ag/AgCl. The amperometry method showed an excellent performance with a sensitivity of 6.83 μA mM(-1) and a detection limit of 11.4 × 10(-7)ML(-1). A linear calibration graph was constructed in the ranging 3.90 × 10(-6) to 3.19 × 10(-5)ML(-1). The method was successfully applied for the determination of Sudan I in red chili powder samples. PMID:25053046

  13. Amperometric detection of Sudan I in red chili powder samples using Ag nanoparticles decorated graphene oxide modified glassy carbon electrode.

    PubMed

    Prabakaran, E; Pandian, K

    2015-01-01

    A simple and sensitive electrochemical method was developed to determine the concentration of Sudan I in chili powder based on silver nanoparticles decorated graphene oxide modified glassy carbon electrode (AgNPs@GO/GCE). The voltammetry behaviour of Sudan I on modified GCE was investigated in phosphate buffer medium (PBS) with various pH ranges and the electron transfer properties were studied. It is found that the AgNPs@GO/GCE can catalyse the reduction of azo group, -N=N- followed by electrochemical oxidation of (-)OH group present in Sudan I dye molecule. Quantitative detection of Sudan I present in food products was carried out by amperometry method in which reduction potential was fixed at -0.77 V vs. Ag/AgCl. The amperometry method showed an excellent performance with a sensitivity of 6.83 μA mM(-1) and a detection limit of 11.4 × 10(-7)ML(-1). A linear calibration graph was constructed in the ranging 3.90 × 10(-6) to 3.19 × 10(-5)ML(-1). The method was successfully applied for the determination of Sudan I in red chili powder samples.

  14. Holocene slip rates along the San Andreas Fault System in the San Gorgonio Pass and implications for large earthquakes in southern California.

    NASA Astrophysics Data System (ADS)

    Heermance, R. V., III; Yule, D.

    2015-12-01

    Since the late 17th century the San Andreas Fault (SAF) in southern California has produced three large (M7.3-7.8) earthquakes that did not break through San Gorgonio Pass (SGP). This pass-as-a-barrier behavior can be explained by the complexity of the SAF system. Here the fault splays and rotates into a series of en-echelon, oblique-dextral thrusts. In the center of SGP two sub-parallel thrusts are 1.5 km apart (the northern (NF) and southern (SF) splays), and form well-preserved fault scarps (up to 15 m high) in at least 3 alluvial fan terraces formed on the Millard Canyon fan. New, 10Be cosmogenic depth profiles and boulder exposure ages constrain the ages of the two oldest Holocene fan surfaces (Qt4, Qt3) to 8900 (range: 7300-11600) and 8300 (range: 6800-10300) y.b.p.. Radiocarbon ages constrain the younger surface (Qt2) at ~1500 y.b.p.. Qt4 contains a 10.5-15.1 m high scarp along the SF and has an uplift rate of 0.9-2.1 mm/yr. Qt3 is inset 1.5 m within Qt4, and contains a 3.6-6.2 m high scarp on the SF and 2.9-5.3 m high scarp on the NF with 0.4-0.9 mm/yr and 0.3-0.8 mm/yr uplift rates, respectively. Qt2 is inset ~4 m within Qt3, and contains a 1.0-2.9 m high scarp on the NF with a 0.9-2.4 mm/yr uplift rate. Using measured fault dips of 45 (NF) and 20-30 (SF) degrees combined with a slip vector inferred from regional GPS data and 2:1 lateral to thrust offset markers, we calculate the net oblique slip rate on these faults at Millard Canyon at 2.1-4.8 mm/yr for Qt4 and 1.0-2.7 mm/yr for Qt3 (SF), and 0.8-2.2 mm/yr for Qt3 and 1.9-6.8 mm/yr for Qt2 (NF). The cumulative slip rate across Millard Canyon (SF+NF) is therefore 1.8-11.6 mm/yr, or more narrowly constrained at 4.0-5.9 mm/yr by using only the overlapping slip rates along each fault strand. An average slip rate of ~5 mm/yr is ~30-70% of the slip rates outside of SGP. This 'slip deficit' may reflect some combination of slip carried by faults within in the San Bernardino Mountains to the north, transferred

  15. C. 1.5 Ga metamorphism of the Lazdijai 13 volcano-sedimentary sequence in southern Lithuania: its origin and implications

    NASA Astrophysics Data System (ADS)

    Siliauskas, Laurynas; Skridlaite, Grazina

    2015-04-01

    The concealed crystalline crust in the SW East European Craton consists of several domains finally accreted at 1.8-1.70 Ga (Bogdanova et al., 2014). However, some geological structures in the Lithuanian basement are still poorly reconstructed because of insufficient isotopic and geochemical data. Such is the Lazdijai 13 (Lz13) volcano-sedimentary sequence in southern Lithuania, preliminary dated at 1.83-1.80 Ga (U-Pb zircon age). The newly obtained monazite analyses (EPMA dating, Cameca SX-100 electron microprobe, Warsaw University) allowed dating of metamorphism of the Lz13 rocks. The 300 m thick Lz13 sequence is composed of deformed and metamorphosed volcanics, volcano-clastics and sediments, cross-cut by pegmatite and quartz veins. The upper part of the drilling (at c. 493 m) consists of exhalitic quartz chlorite cherts and metaandesitic rocks. They are underlain by medium-fine grained shists composed of quartz, biotite, garnet, cordierite, staurolite, minor plagioclase, K-feldspar, magnetite and monazite (felsic volcanics, 540 m) that were metamorphosed at 580° C and 6 kbar (garnet, biotite, cordierite geothermobarometry). Monazites are small, interstitial, fragmented and dissolved, some found as inclusions in magnetite. They yielded three ages: 1685±25 Ma, 1525±11Ma, and 1448±24 Ma. Another layer of a fine grained shist (quartz, biotite, garnet, K-feldspar, muscovite, 599 m) of sedimentary origin contains zircons and monazites arranged in thin, undulating lines. The monazites are small, interstitial, partly dissolved, in places overgrown by alanite aggregates. They yielded 1671±29 Ma and 1523±17 Ma ages. Below, at 757 m, a strongly deformed shist composed of quartz, biotite, K-feldspar, plagioclase, garnet and cordierite (former sediment) was metamorphosed at 498° C and 5.4 kbar (garnet, biotite, plagioclase and muscovite geothermobarometry). It contains very small, strongly dissolved and locally overgrown by alanite, monazite grains. Three of them were

  16. 10Be and U-series dating of late Quaternary landforms along the southern San Jacinto fault: Implications for temporal slip rate variability

    NASA Astrophysics Data System (ADS)

    Blisniuk, K.; Oskin, M. E.; Fletcher, K.; Sharp, W. D.; Rockwell, T. K.

    2009-12-01

    Robust age control on faulted landforms with well-constrained offsets is essential to documenting the heterogeneous behavior of a fault zone over time. However, showing late Quaternary temporal slip rate variation is often challenging due to the difficultly of obtaining reliable ages for Quaternary deposits. Exposure ages from cosmogenic isotopes can be significantly affected by surface processes, and U-series dating of pedogenic carbonate provides only minimum ages because carbonate accumulation occurs after deposition. Fortunately, the controlling factors for the resulting age uncertainties of each method are relatively independent from each other, so a combination of cosmogenic isotope and U-series dating may significantly improve the reliability of landform dating and yield more robust slip rate estimates. We present preliminary results of this dual-dating approach at 4 sites along the southern San Jacinto fault zone in California: 2 sites along the Coyote Creek fault, and 2 sites along the Clark fault. These results show age agreement between the two dating methods. Along the southern Clark fault, a 10Be depth profile model age of 34.5 ±6.6 ka and a U-series age of 33.2 ±1.1 ka were obtained for an offset Q2b fan surface, and a Q3b surface yielded a weighted mean 10Be surface exposure age of 5.9 ±1.5 ka, similar to an U-series age of 6.3 ±0.4 ka. Along the northern Coyote Creek fault, preliminary data indicate a 10Be surface exposure age of 11.3 ±3.4 ka and a U-series age of 11.7 ±1.8 ka for an offset Q3a surface, and a 10Be surface exposure age of 6.9 ±1.0 ka and a U-series age of 7.8 ± 0.9 ka for an offset Q3b surface. The remarkable consistency among ages from the two dating methods suggest that: (1) U-series ages of pedogenic carbonate clast rinds closely approach depositional ages of the host alluvium; (2) erosion may be negligible at the sampled sites; and (3) inherited 10Be has been accurately quantified (via depth profile) for the late

  17. Neoproterozoic chromite-bearing high-Mg diorites in the western part of the Jiangnan orogen, southern China: Geochemistry, petrogenesis and tectonic implications

    NASA Astrophysics Data System (ADS)

    Chen, Xin; Wang, Di; Wang, Xiao-Lei; Gao, Jian-Feng; Shu, Xu-Jie; Zhou, Jin-Cheng; Qi, Liang

    2014-07-01

    High-Mg diorites were discovered in the southern part of the ca. 830 Ma Dongma Pluton, northern Guangxi Province of southern China. The diorites (SiO2 = 59-65 wt%) are characterized by high MgO (6.7-8.9 wt%) contents and Mg-number [Mg# = 100 × Mg/(Mg + Fe)] (69-73), in contrary to the associated medium-Mg (MgO = 3.4-3.8 wt%, Mg# = 59-63) granodiorites in the Dongma main body and the low-Mg (MgO = 1.4-1.9 wt%, Mg# = 46-51) granodiorites in the Bendong Pluton to the north. Moreover, the high-Mg diorites show surprisingly high Cr (595-640 ppm) and Ni (171-194 ppm) concentrations, which are beyond the ranges of most coeval mafic rocks in the study area. Correspondingly, chromite crystals were separated from the high-Mg diorites and some of the medium-Mg granodiorites, and they show high Cr# [100 × Cr/(Cr + Al)] (average of 75), but low Mg# (0.34-2.51) and low Fe3 +. The decoupling of Cr# and Mg# and the existence of quartz + apatite mineral inclusion in chromites suggest Mg-Fe exchange that may be facilitated by the disequilibrium resulted from magma mixing. The high-Mg diorites show low La/Yb (6.8-8.5) and Sr/Y (2.1-3.1) ratios, significant negative anomalies of Nb and Ti and positive anomaly of Pb, resembling the Setouchi high-Mg andesites, despite of their relatively low Sr (71-100 ppm). All of the studied diorites and granodiorites show enriched Nd isotope compositions, with εNd(t) values (- 3.2 to - 5.9) a bit higher than some of the associated mafic rocks. Some of the high-Mg diorites show whole-rock εHf(t) (- 6.0 to - 6.2) coupled with Nd isotopes, similar to the associated mafic-ultramafic rocks in northern Guangxi, suggesting the metasomatism by melts of subducting sediments in the mantle source. Whereas, others show decoupled Nd-Hf isotopes that are similar to the medium- and low-Mg granodiorites [εHf(t) = - 1.8 to + 0.05], probably indicating the late magma mixing with granitic magmas at a crustal level for the dioritic magmas. We propose a two

  18. Evidence for Late-Paleozoic brine migration in Cambrian carbonate rocks of the central and southern Appalachians: Implications for Mississippi Valley-type sulfide mineralization

    USGS Publications Warehouse

    Hearn, P.P.; Sutter, J.F.; Belkin, H.E.

    1987-01-01

    Many Lower Paleozoic limestones and dolostones in the Valley and Ridge province of the central and southern Appalachians contain 10 to 25 weight percent authigenic potassium feldspar. This was considered to be a product of early diagenesis, however, 40Ar 39Ar analyses of overgrowths on detrital K-feldspar in Cambrian carbonate rocks from Pennsylvania, Maryland, Virginia, and Tennessee yield Late Carboniferous-Early Permian ages (278-322 Ma). Simple mass balance calculations suggest that the feldspar could not have formed isochemically, but required the flux of multiple pore volumes of fluid through the rocks, reflecting regional fluid migration events during the Late-Paleozoic Alleghanian orogeny. Microthermometric measurements of fluid inclusions in overgrowths on detrital K-feldspar and quartz grains from unmineralized rocks throughout the study area indicate homogenization temperatures from 100?? to 200??C and freezing point depressions of -14?? to -18.5??C (18-21 wt.% NaCl equiv). The apparent similarity of these fluids to fluid inclusions in ore and gangue minerals of nearby Mississippi Valley-type (MVT) deposits suggests that the regional occurrences of authigenic K-feldspar and MVT mineralization may be genetically related. This hypothesis is supported by the discovery of authigenic K-feldspar intergrown with sphalerite in several mines of the Mascot-Jefferson City District, E. Tennessee. Regional potassic alteration in unmineralized carbonate rocks and localized occurrences of MVT mineralization are both explainable by a gravity-driven flow model, in which deep brines migrate towards the basin margin under a hydraulic gradient established during the Alleghanian orogeny. The authigenic K-feldspar may reflect the loss of K during disequilibrium cooling of the ascending brines. MVT deposits are probably localized manifestations of the same migrating fluids, occurring where the necessary physical and chemical traps are present. ?? 1987.

  19. Retrograde deformation within the Carthage-Colton Zone as recorded by fluid inclusions and feldspar compositions: tectonic implications for the southern Grenville Province

    NASA Astrophysics Data System (ADS)

    Lamb, William M.

    1993-09-01

    The Carthage-Colton Zone (CCZ), located in the northwestern portion of the Proterozoic Adirondack terrane, forms the boundary between the Adirondack lowlands and highlands and is characterized by textures indicative of ductile deformation. Samples from three rock types have been collected from this zone: (1) pyroxene bearing syenite gneisses of the Diana igneous complex; (2) paragneiss samples from near the northwestern boundary of the Diana complex; (3) a quartz-rich metasediment. Feldspar geothermometry performed on the Diana metasyenites shows that porphyroclasts are relict igneous grains that formed at T≈900° C, while dynamic recrystallization occurred at temperatures as low as 470 to 550° C as shown by the compositions of feldspar neoblasts. All samples examined in this study from the CCZ contain a suite of CO2-rich fluid inclusions that are distinctive both texturally and in their microthermometric behavior (Th=-27.7 to-7.1° C) as compared to CO2-rich Adirondack fluid inclusions that do not lie within this zone (Th=-45.9 to +31.0° C). The results from fluid inclusion microthermometry and feldspar geothermometry restrict the conditions of dynamic recrystallization to temperatures and pressures of 400 to 550° C and 3 to 5 kbar. The retrograde pressure-temperature path must pass through these conditions. Similar fluid inclusion results have been obtained from the Parry Sound Shear Zone (PSSZ) which is a Grenvillian shear zone that is located in Southern Ontario (Lamb and Moecher 1992). However, the inferred retrograde P-T paths for these two areas, the CCZ and the PSSZ, are different and this difference may be a result of late deformation along shear zones that are located between the two areas.

  20. Leafcutter Bee Nests and Pupae from the Rancho La Brea Tar Pits of Southern California: Implications for Understanding the Paleoenvironment of the Late Pleistocene

    PubMed Central

    Holden, Anna R.; Koch, Jonathan B.; Griswold, Terry; Erwin, Diane M.; Hall, Justin

    2014-01-01

    The Rancho La Brea Tar Pits is the world’s richest and most important Late Pleistocene fossil locality and best renowned for numerous fossil mammals and birds excavated over the past century. Less researched are insects, even though these specimens frequently serve as the most valuable paleoenvironemental indicators due to their narrow climate restrictions and life cycles. Our goal was to examine fossil material that included insect-plant associations, and thus an even higher potential for significant paleoenviromental data. Micro-CT scans of two exceptionally preserved leafcutter bee nest cells from the Rancho La Brea Tar Pits in Los Angeles, California reveal intact pupae dated between ∼23,000–40,000 radiocarbon years BP. Here identified as best matched to Megachile (Litomegachile) gentilis Cresson (Hymenoptera: Megachilidae) based on environmental niche models as well as morphometrics, the nest cells (LACMRLP 388E) document rare preservation and life-stage. The result of complex plant-insect interactions, they offer new insights into the environment of the Late Pleistocene in southern California. The remarkable preservation of the nest cells suggests they were assembled and nested in the ground where they were excavated. The four different types of dicotyledonous leaves used to construct the cells were likely collected in close proximity to the nest and infer a wooded or riparian habitat with sufficient pollen sources for larval provisions. LACMRLP 388E is the first record of fossil Megachile Latreille cells with pupae. Consequently, it provides a pre-modern age location for a Nearctic group, whose phylogenetic relationships and biogeographic history remain poorly understood. Megachile gentilis appears to respond to climate change as it has expanded its distribution across elevation gradients over time as estimated by habitat suitability comparisons between low and high elevations; it currently inhabits mesic habitats which occurred at a lower elevation

  1. Age and composition of Archean crystalline rocks from the southern Madison Range, Montana. Implications for crustal evolution in the Wyoming craton

    SciTech Connect

    Mueller, P.A.; Shuster, R.D. ); Wooden, J.L. ); Erslev, E.A. ); Bowes, D.R. )

    1993-04-01

    The southern Madison Range of southwestern Montana contains two distinct Precambrian lithologic assemblages: (1) a complex of tonalitic to granitic gneisses that has been thrust over (2) a medium-grade metasupracrustal sequence dominated by pelitic schist. Crystallization ages for the protolith of a granodioritic gneiss that intruded the metasupracrustal sequence ([approximately]2.6 Ga)-along with an intercalated meta-andesite ([approximately]2.7 Ga) confirm the sequence as Archean. Chemical (major and trace element), isotopic (Rb-Sr, Sm-Nd, Pb-Pb), and geochronologic (U-Pb zircon) data for selected components of the gneiss complex indicate two groups of gneisses: an older, tonalitic to trondhjemitic group ([approximately]3.3 Ga) and a younger, mostly granitic group ([approximately]2.7 Ga). Both groups of gneisses exhibit the radiogenic Pb and nonradiogenic Nd isotopic signature characteristic of Middle and Late Archean rocks from throughout the Wyoming province. The older gneisses, in particular, appear to be compositionally, isotopically, and chronologically comparable to other Middle Archean gneisses from the northern part of the province (for example, Beartooth Mountains). The Late Archean gneisses, however, exhibit some distinct differences relative to their temporal counterparts, including (1) trace-element patterns that are more suggestive of crustal melts than subduction activity and (2) higher initial Sr isotopic ratios that suggest more involvement of older crust in their petrogenesis. These comparisons suggest that the juxtaposition of Late Archean terranes in the northern Wyoming province was the result, at least in part, of intracratonic processes. 41 refs., 6 figs., 2 tabs.

  2. Spatial Variability in Ultrafine Particles at Five Sites in Southern Ontario, Canada During BAQS-Met 2007 Campaign: Implication of Regional Nucleation Events

    NASA Astrophysics Data System (ADS)

    Jeong, C.; McGuire, M.; Evans, G.; Rachel, R. Y.; Slowik, J. G.; Abbatt, J. P.; Popescu, R.; Murphy, J.; Zeromskiene, K. G.; Mozurkewich, M.; Leaitch, R.

    2008-12-01

    Ultrafine particle (UFP) measurements were simultaneously conducted in five urban and rural areas; Toronto, Egbert, Ridgetown, Bear Creek, and Harrow in Ontario, Canada as part of the Border Air Quality and Meteorology Study (BAQS-Met 2007). The number and size distributions of UFP in the size range of 14 to 93 nm were measured by a Fast Mobility Particle Sizer (FMPS, TSI 3091) and four Scanning Mobility Particle Sizers (SMPS) from June 19 to July 8, 2007. Continuous measurements of PM2.5 mass and gaseous pollutants (NH3, CO, SO2, NOx, O3) were also performed at the sites. The highest particle concentrations were observed at the rural site in Harrow, whereas lower concentrations were found in Toronto, a metropolitan area. The variability of hourly averaged UFP concentrations were significantly higher at the Harrow and Bear Creek sites indicating low background levels and frequent occurrence of strong particle nucleation events. Regional particle nucleation events were classified by assessing particle formation and growth rates at the five monitoring sites. The influences of pre-existing particles, gaseous pollutants and meteorological parameters on the classified particle nucleation events were evaluated. Spatial variability of UFP was examined by using the coefficient of divergence (COD) of each size bin of UFP. The COD provides relative measure of homogeneity in UPF concentrations in the southern Ontario. On average, the COD value was lower between Harrow and Bear Creek than between Harrow and Ridgetown. The COD values for smaller particles in the size range (14nm-22nm) tended to be higher than the levels for larger particles (25nm-93nm) suggesting size dependent homogeneity. In order to regional distribution and dispersion of UFP with distance, cumulative semivariogram (CSV) technique was used for UFP number concentrations at five sites. Detailed results over the measurement periods will be presented and discussed.

  3. Genesis of an esker-like ridge over the southern Fraser Plateau, British Columbia: Implications for paleo-ice sheet reconstruction based on geomorphic inversion

    NASA Astrophysics Data System (ADS)

    Perkins, Andrew J.; Brennand, Tracy A.; Burke, Matthew J.

    2013-05-01

    Robust interpretations of meltwater systems operating during ice sheet decay are integral to reconstructing deglacial patterns and style. Yet over reliance on meltwater landform morphology with limited attention to morpho-sedimentary relationships, and basin-scale geomorphic and stratigraphic context can lead to unreliable geomorphic inversion-based paleo-ice sheet reconstructions. This problem is illustrated by the evolution of Young Lake esker-like ridge (YLER) formed in the Young Lake basin (YLB) on BC's southern Fraser Plateau during decay of the last Cordilleran Ice Sheet (CIS). We integrate data from digital elevation models, aerial photographs, sedimentary outcrops, water wells and shallow geophysics (ground-penetrating radar, electrical resistivity tomography). Previous interpretations of YLER as both an esker and an ice-contact, poorly-sorted, stratified deposit emplaced by westerly flowing meltwater, imply an eastward retreating ice margin. Geophysical data from a flat-topped component of YLER reveal slipface and planar-bedded sand and gravel overlying lacustrine sediments, characteristic of a Hjulstrom delta. Eastward-dipping foresets in a Gilbert delta exist at the eastern terminus. Contextually our observations suggest, despite esker-like morphology, YLER was not deposited within a subglacial ice tunnel. Instead, it formed through deposition of subaerial outwash between and/or on dead ice in front of a regionally backwasting ice margin. The complex deglacial evolution of YLB, including a drainage reversal and formation of two glacial lakes, supports northwestward backwasting of the CIS and dead ice within YLB. We conclude that accurate geomorphic inversion of meltwater landforms for deglacial paleo-ice sheet reconstruction requires knowledge of landform-scale morpho-sedimentary relationships and basin-scale geomorphic and stratigraphic context.

  4. Evidence for Late-Paleozoic brine migration in Cambrian carbonate rocks of the central and southern Appalachians: Implications for Mississippi Valley-type sulfide mineralization

    NASA Astrophysics Data System (ADS)

    Hearn, Paul P., Jr.; Sutter, John F.; Belkin, Harvey E.

    1987-05-01

    Many Lower Paleozoic limestones and dolostones in the Valley and Ridge province of the central and southern Appalachians contain 10 to 25 weight percent authigenic potassium feldspar. This was considered to be a product of early diagenesis, however, 40Ar /39Ar analyses of overgrowths on detrital K-feldspar in Cambrian carbonate rocks from Pennsylvania, Maryland, Virginia, and Tennessee yield Late Carboniferous-Early Permian ages (278-322 Ma). Simple mass balance calculations suggest that the feldspar could not have formed isochemically, but required the flux of multiple pore volumes of fluid through the rocks, reflecting regional fluid migration events during the Late-Paleozoic Alleghanian orogeny. Microthermometric measurements of fluid inclusions in overgrowths on detrital K-feldspar and quartz grains from unmineralized rocks throughout the study area indicate homogenization temperatures from 100° to 200°C and freezing point depressions of -14° to -18.5°C (18-21 wt.% NaCl equiv). The apparent similarity of these fluids to fluid inclusions in ore and gangue minerals of nearby Mississippi Valley-type (MVT) deposits suggests that the regional occurrences of authigenic K-feldspar and MVT mineralization may be genetically related. This hypothesis is supported by the discovery of authigenic K-feldspar intergrown with sphalerite in several mines of the Mascot-Jefferson City District, E. Tennessee. Regional potassic alteration in unmineralized carbonate rocks and localized occurrences of MVT mineralization are both explainable by a gravity-driven flow model, in which deep brines migrate towards the basin margin under a hydraulic gradient established during the Alleghanian orogeny. The authigenic K-feldspar may reflect the loss of K during disequilibrium cooling of the ascending brines. MVT deposits are probably localized manifestations of the same migrating fluids, occurring where the necessary physical and chemical traps are present.

  5. The Structure Difference in the Southern Margin of the Dangerous Grounds: Implications for the Final Evolution of the South China Sea

    NASA Astrophysics Data System (ADS)

    Xi, P.; Shen, C.; Zhao, Z.; Xie, X.; Mei, L.; Gong, J.; Huang, X.

    2015-12-01

    We interpret two multi-channel seismic reflection profiles, more than 900 km across the entire Dangerous Grounds, locating in east and west of the southern margin of the South China Sea respectively. Eight Cenozoic sequence boundaries are determined as well as three tectono-stratigraphic units. Detailed analysis of extensional features and unconformities revealed the tectonic in the east and west. Early extension (syn-rifting sequence) occurred in the two profiles during continental rifting, which lasted from Palaeocene to Early Oligocene, and resulted in formation of half-grabens and rotated fault-blocks. Late extension (drift-rifting sequence) has the significant difference in the both profiles. The eastern Dangerous Grounds entered rifting-depression stage and some compressional deformation occurred in the Reed Bank basin at about the beginning of Early Miocene, probably resulting from the collision of the Dangerous Grounds and the Sabah-Cagayan Arc. The western Dangerous Grounds was still in rifting until the end of Early Miocene, forming the MMU or DRU which is strongly erosional and represents a major break in sedimentation and/or erosion in partial area. Denudation fold and inverted fault can be distinguished blow the MMU, indicating the cessation of the South China Sea accompanied the NW compression, while the boundary corresponding the MMU is nearly a plano-conformity in the east. The thermal sag (post-rifting sequence) is characterized by non-faulted draping strata in the whole area. The different structure in east and west may be related to the final evolution of the SCS. When the proto-SCS closed in a scissor fashion plus the clockwise rotation of Borneo, the initial collision (c.20Ma) appeared in east part building the NW foreland basin system from Palawan Trough to Reed Bank in a short-live process, while the west part was drifting southwards until c.15Ma to form the even more remarkable foreland system from Borneo Trough to deep-water Sarawak.

  6. A 250,000-year record of lunette dune accumulation on the Southern High Plains, USA and implications for past climates

    NASA Astrophysics Data System (ADS)

    Rich, Julie

    2013-02-01

    A concentration of lake/playa basins occurs on the Southern High Plains (SHP) of northwest Texas and eastern New Mexico. Associated with these lake/playas are lee-side lunettes positioned on their southeast margins ranging in height from 1.5 to >10 m. An OSL dating program was applied to 30 samples from lunettes associated with large lakes and small playa basins. Samples were extracted from trenched dune sections or from deep cores. Earlier SHP lunette investigations show depositional ages primarily in the late Wisconsin and Holocene. This research extends the timing of lunette accretion to the middle Pleistocene, the earliest recorded deposition for these features. The expanded chronology permitted investigation into dune morphology on nested lunettes built on contracting lake margins. Outer lunettes formed prior to inner dunes, but simultaneous deposition occurred on downwind ridges as younger lee-side dunes were constructed. Large lake lunettes were inactive during discreet SHP pluvial episodes from early Wisconsin to LGM. Conversely, these lunettes accreted when climatic conditions promoted basin desiccation and aeolian deflation. This suggests their mode of formation contrasts with lunette models recognized for other regions. From post LGM to earliest Holocene, active lunette accretion occurred from 16 to 11 ka followed by a significant period of lunette construction during the mid-Holocene. Late Holocene-lunette deposition was interrupted by intervals of landscape stability. Lunette deposition between 1300s and 1700s corresponds with drought intervals recognized in tree-ring records from adjacent regions. Recent lunette activity on the plateau is contemporary with the 1930's 'dust bowl'. Further insight into SHP response to changing climatic conditions was given by comparing lunette depositional events with previous investigations on sedimentation intervals for draws, lake/playa basins, and sand sheets.

  7. Mineralogy and geochemistry of pseudogley soils and recent alluvial clastic sediments in the Ngog-Lituba region, Southern Cameroon: An implication to their genesis

    NASA Astrophysics Data System (ADS)

    Ndjigui, Paul-Désiré; Ebah Abeng, Sandrine Appolonie; Ekomane, Emile; Nzeukou, Aubin Nzeugang; Ngo Mandeng, Francine Sidonie; Matoy Lindjeck, Marthe

    2015-08-01

    Mineralogical and geochemical investigations have been done on the hydromorphic clays (pseudogley soils and recent alluvial clastic sediments) in the Sanaga Maritime region (Southern Cameroon). Pseudogley soils are developed on gneisses from the Yaoundé Group. They have a dark brown to greyish brown color, with silty clay texture. Their mineral assemblage is made up of kaolinite, goethite, quartz, smectite, rutile, muscovite-illite and feldspars. The alluvial clastic sediments are characterized by variable colors (purple yellow, greenish, dark brown and purple brown) and sandy clay to clay texture. The mineral assemblage of alluvial clays is similar to that of pseudogley soils. SEM observations confirm the presence of kaolinite, smectite, quartz and muscovite-illite. Infrared data show that kaolinite is more orderly in pseudogley than in the alluvial clastic sediments. The Ngog-Lituba gneisses have moderate contents in SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O and several trace elements including REE. High element depletion is noticed in the pseudogley soils except Cr, V, Zr, Pb and REE. However, the alluvial clays are marked by a strong mobilization of LILE (Na, K, Ba, Rb and Sr) and REE, relative to the parent rock and pseudogley soils. The chondrite-normalized REE patterns are homogenous and parallel with Ce-anomalies. The (La/Yb)N shows that the REE fractionation increase from the parent rock to the alluvial clastic sediments. The mineralogical and geochemical features show that the clastic river sediments are derived from the erosion of the neighboring pseudogley materials before hydraulic sorting.

  8. Leafcutter bee nests and pupae from the Rancho La Brea Tar Pits of Southern California: implications for understanding the paleoenvironment of the Late Pleistocene.

    PubMed

    Holden, Anna R; Koch, Jonathan B; Griswold, Terry; Erwin, Diane M; Hall, Justin

    2014-01-01

    The Rancho La Brea Tar Pits is the world's richest and most important Late Pleistocene fossil locality and best renowned for numerous fossil mammals and birds excavated over the past century. Less researched are insects, even though these specimens frequently serve as the most valuable paleoenvironemental indicators due to their narrow climate restrictions and life cycles. Our goal was to examine fossil material that included insect-plant associations, and thus an even higher potential for significant paleoenviromental data. Micro-CT scans of two exceptionally preserved leafcutter bee nest cells from the Rancho La Brea Tar Pits in Los Angeles, California reveal intact pupae dated between ∼23,000-40,000 radiocarbon years BP. Here identified as best matched to Megachile (Litomegachile) gentilis Cresson (Hymenoptera: Megachilidae) based on environmental niche models as well as morphometrics, the nest cells (LACMRLP 388E) document rare preservation and life-stage. The result of complex plant-insect interactions, they offer new insights into the environment of the Late Pleistocene in southern California. The remarkable preservation of the nest cells suggests they were assembled and nested in the ground where they were excavated. The four different types of dicotyledonous leaves used to construct the cells were likely collected in close proximity to the nest and infer a wooded or riparian habitat with sufficient pollen sources for larval provisions. LACMRLP 388E is the first record of fossil Megachile Latreille cells with pupae. Consequently, it provides a pre-modern age location for a Nearctic group, whose phylogenetic relationships and biogeographic history remain poorly understood. Megachile gentilis appears to respond to climate change as it has expanded its distribution across elevation gradients over time as estimated by habitat suitability comparisons between low and high elevations; it currently inhabits mesic habitats which occurred at a lower elevation during

  9. Basin geometry and cumulative offsets in the Eastern Transverse Ranges, southern California: Implications for transrotational deformation along the San Andreas fault system

    USGS Publications Warehouse

    Langenheim, V.E.; Powell, R.E.

    2009-01-01

    The Eastern Transverse Ranges, adjacent to and southeast of the big left bend of the San Andreas fault, southern California, form a crustal block that has rotated clockwise in response to dextral shear within the San Andreas system. Previous studies have indicated a discrepancy between the measured magnitudes of left slip on through-going east-striking fault zones of the Eastern Transverse Ranges and those predicted by simple geometric models using paleomagnetically determined clockwise rotations of basalts distributed along the faults. To assess the magnitude and source of this discrepancy, we apply new gravity and magnetic data in combination with geologic data to better constrain cumulative fault offsets and to define basin structure for the block between the Pinto Mountain and Chiriaco fault zones. Estimates of offset from using the length of pull-apart basins developed within left-stepping strands of the sinistral faults are consistent with those derived by matching offset magnetic anomalies and bedrock patterns, indicating a cumulative offset of at most ???40 km. The upper limit of displacements constrained by the geophysical and geologic data overlaps with the lower limit of those predicted at the 95% confidence level by models of conservative slip located on margins of rigid rotating blocks and the clockwise rotation of the paleomagnetic vectors. Any discrepancy is likely resolved by internal deformation within the blocks, such as intense deformation adjacent to the San Andreas fault (that can account for the absence of basins there as predicted by rigid-block models) and linkage via subsidiary faults between the main faults. ?? 2009 Geological Society of America.

  10. Petrology and geochemistry of primitive lower oceanic crust from Pito Deep: Implications for the accretion of the lower crust at the Southern East Pacific Rise

    USGS Publications Warehouse

    Perk, N.W.; Coogan, L.A.; Karson, J.A.; Klein, E.M.; Hanna, H.D.

    2007-01-01

    A suite of samples collected from the uppermost part of the plutonic section of the oceanic crust formed at the southern East Pacific Rise and exposed at the Pito Deep has been examined. These rocks were sampled in situ by ROV and lie beneath a complete upper crustal section providing geological context. This is only the second area (after the Hess Deep) in which a substantial depth into the plutonic complex formed at the East Pacific Rise has been sampled in situ and reveals significant spatial heterogeneity in the plutonic complex. In contrast to the uppermost plutonic rocks at Hess Deep, the rocks studied here are generally primitive with olivine forsterite contents mainly between 85 and 88 and including many troctolites. The melt that the majority of the samples crystallized from was aggregated normal mid-ocean ridge basalt (MORB). Despite this high Mg# clinopyroxene is common despite model predictions that clinopyroxene should not reach the liquidus early during low-pressure crystallization of MORB. Stochastic modeling of melt crystallisation at various levels in the crust suggests that it is unlikely that a significant melt mass crystallized in the deeper crust (for example in sills) because this would lead to more evolved shallow level plutonic rocks. Similar to the upper plutonic section at Hess Deep, and in the Oman ophiolite, many samples show a steeply dipping, axis-parallel, magmatic fabric. This suggests that vertical magmatic flow is an important process in the upper part of the seismic low velocity zone beneath fast-spreading ridges. We suggest that both temporal and spatial (along-axis) variability in the magmatic and hydrothermal systems can explain the differences observed between the Hess Deep and Pito Deep plutonics. ?? Springer-Verlag 2007.

  11. Tibet and Beyond: Magmatic Records from CIA (Caucasus-Iran-Anatolia) and Southern Tibet with Implications for Asian Orogeny and Continental Growth

    NASA Astrophysics Data System (ADS)

    Chung, Sun-Lin

    2016-04-01

    This study, based on an ongoing joint research project "Tibet and Beyond", presents a synthesis of principal magmatic records from the CIA (Caucasus-Iran-Anatolia) and Tibet-Himalaya orogens resulting from the continental collisions of Arabia and India, respectively, with Eurasia. In both orogens, through this and other recent studies, the temporal and spatial variations in magmatism pre-, syn- and post-dating the collisions can now be much better defined, thus improving our understanding of collision zone magmatism that appears to have evolved with changes in the lithospheric structures over time and space by collisional processes. The two "collisional" Tethyan orogens were preceded by accretionary orogenic processes, which not only had produced a substantial amount of juvenile continental crust but also fulfill the "orogenic cycle" that evolved from an accretionary into a collisional system. Geochemical data reveal that in contrast to generating vast portions of juvenile crust in the early, accretionary stages of orogenic development, crustal recycling plays a more important role in the later, collisional stages. The latter, as exemplified in SE Turkey and southern Tibet, involves addition of older continental crust material back into the mantle, which subsequently melted and caused compositional transformation of the juvenile crust produced in the accretionary stages. Similar features are observed in young volcanic rocks from eastern Taiwan, the northern Luzon arc complex and part of the active subduction/accretion/collision system in Southeast Asia that may evolve one day to resemble the eastern Tethyan and central Asian orogenic belts by collision with the advancing Australian continent.

  12. Petrogenesis of Middle-Late Triassic volcanic rocks from the Gangdese belt, southern Lhasa terrane: Implications for early subduction of Neo-Tethyan oceanic lithosphere

    NASA Astrophysics Data System (ADS)

    Wang, Chao; Ding, Lin; Zhang, Li-Yun; Kapp, Paul; Pullen, Alex; Yue, Ya-Hui

    2016-10-01

    The Gangdese belt is dominantly composed of igneous rocks that formed during the northward subduction of Neo-Tethyan oceanic lithosphere beneath the Lhasa terrane and has played a crucial role in understanding the pre-collisional evolution of southern Tibet. This paper presents new geochronological and geochemical (whole-rock major and trace element and Sr-Nd and zircon Hf isotope) data for recently identified volcanic rocks exposed in Changguo area, southernmost part of the Lhasa terrane. Zircon U-Pb dating from six samples yields consistent ages of 237.1 ± 1.1 Ma to 211.7 ± 1.5 Ma for magma emplacement through volcanic eruption, showing the Middle-Late Triassic magmatic activity in the southernmost Gangdese Belt. The Changguo volcanic rocks are mainly composed of basaltic and andesitic rocks and exhibit LILE enrichment and HFSE depletion. They also exhibit relatively uniform Nd-Hf isotopic compositions (εNd(t) = + 5.20 to + 7.74 and εHf(t)zircon = + 10.2 to + 15.9). The basaltic magmas were likely sourced from partial melting of sub-arc mantle wedge that was metasomatized by not only the aqueous fluid derived from subducting altered oceanic crust but also hydrous melt derived from subducting seafloor sediments, and subsequently experienced fractional crystallization and juvenile crustal contamination during ascent. The andesitic magmas were generated by partial melting of mafic-ultramafic metasomes through melt/fluid-peridotite reaction at slab-mantle interface. Taking into account the temporal and spatial distribution of the Early Mesozoic magmatic rocks and regional detrital zircon data, we further propose that the northward subduction of Neo-Tethyan oceanic lithosphere beneath the Lhasa terrane commenced by Middle Triassic.

  13. A 400-kyr record of millennial-scale carbonate preservation events in the Southern Ocean: Implications for Atlantic Meridional Overturning Circulation and atmospheric CO2

    NASA Astrophysics Data System (ADS)

    Hodell, D. A.; Vautravers, M. J.; Barker, S.; Charles, C.; Crowhurst, S.

    2014-12-01

    . The increased flux of carbonate ion to the Southern Ocean during strong interstadials may have played a role in titrating respiratory CO2, thereby slowing CO2 degassing to the atmosphere and providing a secondary mechanism, in addition to heat transport, for interhemispheric coupling on millennial time scales.

  14. Platinum group minerals in ophiolitic chromitites from Tehuitzingo (Acatlán complex, southern Mexico): implications for post-magmatic modification

    NASA Astrophysics Data System (ADS)

    Zaccarini, F.; Proenza, J. A.; Ortega-Gutiérrez, F.; Garuti, G.

    2005-07-01

    Podiform chromitite bodies occur in serpentinites at Tehuitzingo (Acatlán complex, southern Mexico). Serpentinite and chromitite are believed to represent a fragment of Paleozoic ophiolitic mantle formed in a supra-subduction zone setting. The ophiolitic mantle sequence is associated with eclogitic rocks, enclosed in a metasedimentary sequence. This association suggests that serpentinites, chromitites and eclogitic rocks underwent a common metamorphic evolution, starting from high pressure (eclogite facies) followed by retrogression (epidote-amphibolite and greenschist facies). The chromitites are strongly altered so that chromite grains are transformed to ferrian chromite; no primary silicates (i.e. of magmatic origin) have been preserved. The chromitites are Al-rich, and contain up to 303 ppb platinum group elements (PGE), with a marked predominance of Os + Ir + Ru over Rh + Pd + Pt, resulting in a characteristic negative-slope of the chondrite-normalized PGE pattern. Consistent with the geochemical data the platinum group minerals (PGM) assemblage is dominated by Ru Os Ir minerals, occurring both as single-phase or as composite grains generally less than 10 µm in size. The PGM mineralogy includes laurite, osmium, irarsite and Ru Fe oxide or hydroxide. Based on textural relations, paragenesis and composition, it was possible to establish that Os-rich laurite and irarsite were early liquidus phases, which now occur as inclusions in unaltered chromite. However, most of the PGM are found in the alteration assemblages of the chromitites in close association with ferrian chromite, chlorite, and heazlewoodite. Laurite from the secondary assemblage is Os-poor and commonly shows overgrowths of Os Ir alloys. Internal zoning of some laurite grains indicates that Os-poor laurite formed from a Os-rich laurite by release of Os and some Ir, that are readily incorporated in the Os Ir alloys. Such process requires a decrease of sulfur fugacity with decreasing temperature; this

  15. High frequency peritidal cycles of the upper Araras Group: Implications for disappearance of the neoproterozoic carbonate platform in southern Amazon Craton

    NASA Astrophysics Data System (ADS)

    Rudnitzki, Isaac Daniel; Romero, Guilherme Raffaeli; Hidalgo, Renata; Nogueira, Afonso Cesar Rodrigues

    2016-01-01

    activity in the vicinity of the basin and the rapid uplift of source areas to the west and to the east of the basin preceding the progradation of the siliciclastic fluvial-coastal environments related to the Alto Paraguay sedimentation. This event resulted in erosion of shallow carbonate basins and, potentially, the demise and disintegration of the Neoproterozoic carbonate platforms in southern Amazon Craton.

  16. Geochronology, structural evolution of the Tierra Colorada area, and tectonic implications for southern Mexico and Chortís block connections

    NASA Astrophysics Data System (ADS)

    Solari, L. A.; Torres de Leon, R.; Hernandez Pineda, G.; Sole', J.; Solis Pichardo, G.; Hernandez Treviño, T.

    2006-05-01

    The Tierra Colorada area is considered the best exposure of the northern limit between the Xolapa Complex and the Paleozoic-Precambrian Mixteca and Zapotecan terranes of southern Mexico. Geochemistry (major, trace, and REE) and geochronology on deformed granitoids in Tierra Colorada area show evidence of subduction-related magmatism during Mesozoic and Cenozoic. El Pozuelo granite, dated at 129 Ma (concordant U-Pb single-zircon age) is a foliated body, with local porphyric facies. Foliation is penetrative and characterized by oriented micas and stretched quartz. Geochemically it shows a metaluminous character, with arc-related trace and REE patterns. Because it cuts across high-grade gneisses of the Xolapa Complex, its intrusion postdates the second phase of metamorphism in the Xolapa Complex (> 130 Ma), which generated the orthogneisses-migmatites sequence. El Salitre granite (55 Ma, Rb-Sr 4 point isochron) is a foliated peraluminous body with a pronounced negative Zr anomaly. The protomylonitic Las PiÑas granite (54 +/- 6 Ma, U-Pb lower intercept) is characterized by ductile fabric, recognized by cinematic indicators such as mica fish, and indicates a top-to-the NNW sense of shear, dated at 50 +/- 1 Ma and 45.3 +/- 2 Ma (K-Ar on Bt, and Rb-Sr Bt-WR isochron, respectively), ages that indicate the time of ductile deformation along La Venta shear zone, as N-dipping detachment under low greenschist facies conditions. El Salitre and Las PiÑas granites are linked because of their similar HREE patterns. The Tierra Colorada, Xaltianguis and San Juan del Reparo granites, with calcalkaline subduction-related geochemistry, lack of penetrative deformation, and their ages of 30-34 Ma (U-Pb on zircons) constitute the last recognized granitic pulse in this area, post-dating the S-verging thrust of the Morelos limestones on top of sheared granites and volcanics. Together with previously published ages of magmatism in the studied area, we demonstrate here that calcalkaline

  17. Characterization and origin of the Taishanmiao aluminous A-type granites: implications for Early Cretaceous lithospheric thinning at the southern margin of the North China Craton

    NASA Astrophysics Data System (ADS)

    Wang, Changming; Chen, Liang; Bagas, Leon; Lu, Yongjun; He, Xinyu; Lai, Xiangru

    2016-07-01

    Late Mesozoic magmatic rocks from the Taishanmiao Batholith were collected for LA-ICP-MS dating, Sr-Nd-Hf isotope systematics, and whole-rock major and trace element geochemistry to help understand the nature of collisional and extensional events along the southern margin of the North China Craton. The batholith consists of three texturally distinguishable phases of a 125 ± 1 Ma medium- to coarse-grained syenogranite, a 121 ± 1 Ma fine- to medium-grained syenogranite, and a 113 ± 1 Ma porphyritic monzogranite. Most of the units in the batholith are syenogranitic in composition with high levels of silica (70-78 wt% SiO2), alkalis (8.0-8.6 wt% Na2O + K2O), Fe* (FeOT/(FeOT + MgO) = 0.76-0.90), and depletion in CaO (0.34-1.37 wt%), MgO (0.12-0.52 wt%), TiO2 (0.09-0.40 wt%), and A/CNK (Al2O3/(Na2O + K2O + CaO)) molar ratios of 1.00-1.11. All samples have high proportions of Ga, Nb, Zr, Ga/Al, and REE, and depletions in Ba, Sr, Eu, and compatible elements, indicating that the batholith consists of A-type granites. The zircon saturation temperature for these units yields a mean value of 890 °C, and zircons with Early Cretaceous magmatic ages have ɛNd( t) values of -14.0 to -12.0, ɛHf( t) values ranging from -18.7 to -2.1, and corresponding Hf model ages of 2339-1282 Ma. These geochemical and isotopic characteristics allowed us to conclude that the primary magma for the Taishanmiao Batholith originated from partial melting of Precambrian crustal rocks in the medium-lower crust. However, the high Nb and Ta contents and low normalized Nb/Ta values for the Taishanmiao granites are due to fractionation in Nb- and Ta-rich amphibole (or biotite). It is further proposed that these aluminous A-type granites were generated in an extensional tectonic setting during the Early Cretaceous, which was induced by lithospheric thinning and asthenospheric upwelling beneath eastern China toward the Paleo-Pacific Plate.

  18. Benthic Epiphytic Diatoms in Deep-sea Southern Ocean Sediments as a New Tool for Reconstructing Antarctic Paleoclimatic and Paleoceanographic History: Implications of Floating 'Macroalgal Biotic Oases'

    NASA Astrophysics Data System (ADS)

    Harwood, D. M.; Porter, N.; OConnell, S.

    2014-12-01

    A new paleobiological proxy for Antarctic paleoclimate history provides insight into past extent of open marine shelves on Wilkes Land margin, and calls for reassessment of IRD interpretations in the deep-sea. Marine, epiphytic benthic diatoms that grow attached to macroalgae (seaweed) are recovered in Miocene sediment from DSDP Site 269. They suggest periodic presence of floating rafts or 'biotic oases' in the Southern Ocean comprising buoyant macroalgae, attached benthic diatoms, and biota associated with this displaced coastal community. Macroalgae attach to the substrate with a holdfast, a multi-fingered structure that serves as an anchor. Uprooted holdfasts attached to buoyant macroalgae can raft sedimentary particles, some large (>50 kg), into the deep-sea. In addition, a rich biota of associated invertebrates live in cavities within the holdfast, the dispersal of which may explain the biogeographic distribution of organisms on Subantarctic islands. The stratigraphic occurrence of large, benthic epiphytic diatoms of genera Arachnoidiscus, Isthmia, Rhabdonema, Gephyra, Trigonium, and smaller Achnanthes, Cocconeis, Grammatophora, and Rhaphoneis in sediment cores from DSDP Site 269 reflect a rich, productive epiphytic diatom flora that maintained its position in the photic zone attached to their buoyant seaweed hosts. Amphipods and other herbivores grazed the benthic diatoms and produced diatom-rich fecal pellets that were delivered to the sea-floor. The discontinuous stratigraphic occurrence of the epiphytic diatoms, amongst the background of planktonic diatoms in Core 9 of DSDP Site 269, suggests environmental changes induced by either warm or cold events may have controlled the production and/or release of the macroalgae into the deep-sea. Warm events led to increased shelf areas, and cold events led to formation of ice on the macroalgae to increase their buoyancy and lift-off. Complicating the distinction between warm and cold events is the potential for the

  19. Implication of the southern Tethyan Himalaya (Sutlej section, India) for the extrusion of the Higher Himalaya and the geometry of the mid-crustal channel

    NASA Astrophysics Data System (ADS)

    Mukherjee, Soumyajit

    2013-04-01

    In the last three years, various combinations of channel flow and critical taper mechanisms have been suggested as plausible mechanism for the extrusion of the Higher Himalaya (HH, Beaumont and Jamieson 2010; Chambers et al., 2011; Larson et al., 2011; Corrie et al., 2012; Long et al. 2012; Mukherjee, in press). An alternate and rather less popular model of the HH has been southward droop of the northern boundary of the HH viz. the 'South Tibetan Detachment System-Upper (STDSU)' (Exner et al. 2006). Had the later been true, drag folds with southward vergence would be expected immediately north of the STDSU. In a SW to NE traverse from Morang up to Spillo along the Sutlej river valley (Himachal Pradesh, India), such folds do occur within the southern part of the Tethyan Himalaya. On close observation, the primary shear planes of top-to~S shear are overturned by folds with broad rounded hinges and with ~ NE dipping axial planes and limbs. The shear sense indicated by the sigmoid fabrics matches with the asymmetry of the folds. Northward from Spillo, large-scale folds (antiforms) with down-dip extensional shear in both limbs indicate 'irregular' doming of the Tethyan sediments. One of the best exposures of this shear sense that could be deciphered even from a distance is where the National Highway 22 running along the river valley joins the road to Nasang village. Below the Tethyan sediments, a mid-crustal sub-horizontal channel is widely accepted to allow the Higher Himalayan rock materials to flow from beneath south Tibet. Much north of Spillo, the Leo Pargil granite-gneiss dome has been suggested as an exposure of the channel materials. Thus, this work suggests (i) flap of the STDSU might have triggered the extrusion of the HH; and (ii) doming of a part of the Tethyan Himalaya could be due to the rise of low-density hot, partially molten rocks through the sub-horizontal channel. This would imply that the upper boundary of the sub-horizontal channel was flexible

  20. Vegetation and geomorphic significance of the riparian greenline in the Sprague River basin, southern Oregon: implications for biogeomorphic monitoring of riparian corridors in semi-arid mountain valleys

    NASA Astrophysics Data System (ADS)

    Hughes, M. L.; Leeseberg, C.

    2009-12-01

    Like many regions in the western U.S., valley-floor environments of the semi-arid Sprague River basin of southern Oregon are heavily irrigated and widely grazed by cattle. To better understand the impacts of grazing and other land uses on river quality, the Klamath Tribes have begun a long-term, basin-wide program aimed at: (1) establishing baseline geomorphic and vegetative conditions along the Sprague River and its tributaries, and (2) monitoring changes in these conditions over time. Because of its widespread use and ease of application, determining the composition of the lowest line of perennial vegetation above baseflow, or the “greenline,” has been included. The goal of this paper is to summarize results of 38 greenline surveys conducted at 19 sites in 2008-9 and to explore geomorphic hypotheses that may explain vegetation patterns evident in the surveys. Spikerush (Eleocharis ssp.) and reed-canary grass (Phalaris arudinacea) were the most commonly occurring vegetation in the greenline across all sites. Because these species are aggressive colonizers, they indicate high availability of fresh alluvium, which may be associated with sustained channel-bank disturbance. Sedges dominated some portions of the greenline at most of the sites, but occurred in less abundance. The late successional or early-to-late transitional state of these sedges, combined with their relatively low frequency, further supports the hypothesis that channel-bank systems remain chronically disturbed and dynamic. Grazing is common, but variable in intensity, at nearly all of the study sites, likely contributing to the persistence of channel-bank disturbance. Among meandering channels, the richness of dominant species (i.e., “community diversity”) was higher on the outer bends than on the inner bends of meanders at 10 of 12 sites. The variability of geomorphic surfaces (old floodplain, new floodplain, failed bank, accreted toe, etc.) incorporated in the greenline by the spatially

  1. Tectonics and geochronology of the northern margin of the Zhongba terrane, Southern Tibet: implications for the closing processes of the western Neo-Tethys

    NASA Astrophysics Data System (ADS)

    Liu, Q.; Li, S.; DONG, Y.; Han, G.

    2015-12-01

    The Zhongba terrane represents a special tectonic unit sitting between the northern and the southern ophiolitic sub-belt in the western segment of the Yarlung Zangbo Suture Zone (YZSZ), which separates the Indian and the Eurasian continental plates. The central-east section of the Zhongba terrane can be divided into fault-fold belt, fold belt and fault belt. The fault-fold belt, composed of northward-dipping thrust faults and asymmetric folds in the Carboniferous and late Devonian strata, mainly occurs at the northern margin of the Zhongba terrane. Four stages of deformation (D1-D4) can be recognized in this belt. Stage D1 is recorded by the rolling folds in the Devonian strata in which the residual S0 can be observed in asymmetric small folds. Quartz c-axis fabrics show that the dominant slip system of quartz is basal under transpression and low temperature (~ 400℃). In the stage D2, many small folds with axial plane inclined at high angle to the north were formed. The highly inclined C foliation in mylonitic limestones suggests that this belt represents the strain concentration zone during the northward subduction of the Neo-Tethyan lithosphere beneath the Gangdese arc belt. Coaxial progressive deformation is demonstrated by strongly shortened layers and abundant cleavages that are parallel to the axial plane of pre-existing folds in the stage D3. Mylonitic foliation is replaced by the cleavages plane (S2) associated with southward thrusts. In the stage D4, some northward thrusts and relevant cleavage with medium angle replaced early folds. Zircon U-Pb ages