Sample records for african middle belt

  1. Addressing diarrhea prevalence in the West African Middle Belt: social and geographic dimensions in a case study for Benin

    Arouna Aminou


    Full Text Available Abstract Background In West Africa, the Northern Sahelian zone and the coastal areas are densely populated but the Middle Belt in between is in general sparsely settled. Predictions of climate change foresee more frequent drought in the north and more frequent flooding in the coastal areas, while conditions in the Middle Belt will remain moderate. Consequently, the Middle Belt might become a major area for immigration but there may be constraining factors as well, particularly with respect to water availability. As a case study, the paper looks into the capacity of the Middle Belt zone of Benin, known as the Oueme River Basin (ORB, to reduce diarrhea prevalence. In Benin it links to the Millennium Development Goals on child mortality and environmental sustainability that are currently farthest from realization. However, diarrhea prevalence is only in part due to lack of availability of drinking water from a safe source. Social factors such as hygienic practices and poor sanitation are also at play. Furthermore, we consider these factors to possess the properties of a local public good that suffers from under provision and requires collective action, as individual actions to prevent illness are bound to fail as long as others free ride. Methods Combining data from the Demographic Health Survey with various spatial data sets for Benin, we apply mixed effect logit regression to arrive at a spatially explicit assessment of geographical and social determinants of diarrhea prevalence. Starting from an analysis of these factors separately at national level, we identify relevant proxies at household level, estimate a function with geo-referenced independent variables and apply it to evaluate the costs and impacts of improving access to good water in the basin. Results First, the study confirms the well established stylized fact on the causes of diarrhea that a household with access to clean water and with good hygienic practices will, irrespective of

  2. Meningococcal carriage in the African meningitis belt


    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent ...

  3. Meningococcal carriage in the African meningitis belt


    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  4. African Muslim Youth and the Middle East

    Ihle, Annette Haaber

    express as their expectations that they will through Islamic studies get an opportunity to move upwards socially and materially. Therefore, they dream of going abroad to study in the Middle East. For the time being, religious study grants to the Middle East seem to be one of the few ways for them to gain...... part in the adventures and experiences of globalization in a socially and religiously acceptable way. With its high reputation the al-Azhar in Cairo, Egypt, has played a central role for the establishment of this tradition of religious study trips in an African context. On the basis of 10 months of...

  5. Middle East and North African Oil.

    Al-Quazzaz, Ayad


    Traces the history of oil and natural gas in the Middle East and relates the importance of the Middle East's current stores of oil to economic development. Information is presented on the relationship of major oil companies and local governments, OPEC, rate of production, and the impact of oil on the societies of the Middle East and North Africa.…

  6. Role of dust direct radiative effect on the tropical rain belt over Middle East and North Africa: A high-resolution AGCM study

    Bangalath, Hamza Kunhu; Stenchikov, Georgiy


    To investigate the influence of direct radiative effect of dust on the tropical summer rain belt across the Middle East and North Africa (MENA), the present study utilizes the high-resolution capability of an Atmospheric General Circulation Model, the High-Resolution Atmospheric Model. Ensembles of Atmospheric Model Intercomparison Project style simulations have been conducted with and without dust radiative impacts, to differentiate the influence of dust on the tropical rain belt. The analysis focuses on summer season. The results highlight the role of dust-induced responses in global- and regional-scale circulations in determining the strength and the latitudinal extent of the tropical rain belt. A significant response in the strength and position of the local Hadley circulation is predicted in response to meridionally asymmetric distribution of dust and the corresponding radiative effects. Significant responses are also found in regional circulation features such as African Easterly Jet and West African Monsoon circulation. Consistent with these dynamic responses at various scales, the tropical rain belt across MENA strengthens and shifts northward. Importantly, the summer precipitation over the semiarid strip south of Sahara, including Sahel, increases up to 20%. As this region is characterized by the "Sahel drought," the predicted precipitation sensitivity to the dust loading over this region has a wide range of socioeconomic implications. Overall, the study demonstrates the extreme importance of incorporating dust radiative effects and the corresponding circulation responses at various scales, in the simulations and future projections of this region's climate.

  7. Triple junction orogeny: tectonic evolution of the Pan-African Northern Damara Belt, Namibia

    Lehmann, Jérémie; Saalmann, Kerstin; Naydenov, Kalin V.; Milani, Lorenzo; Charlesworth, Eugene G.; Kinnaird, Judith A.; Frei, Dirk; Kramers, Jan D.; Zwingmann, Horst


    Trench-trench-trench triple junctions are generally geometrically and kinematically unstable and therefore can result at the latest stages in complicated collisional orogenic belts. In such geodynamic sites, mechanism and timescale of deformations that accommodate convergence and final assembly of the three colliding continental plates are poorly studied. In western Namibia, Pan-African convergence of three cratonic blocks led to pene-contemporaneous closure of two highly oblique oceanic domains and formation of the triple junction Damara Orogen where the NE-striking Damara Belt abuts to the west against the NNW-striking Kaoko-Gariep Belt. Detailed description of structures and microstructures associated with remote sensing analysis, and dating of individual deformation events by means of K-Ar, Ar-Ar (micas) and U-Pb (zircon) isotopic studies from the Northern Damara Belt provide robust constraints on the tectonic evolution of this palaeo-triple junction orogeny. There, passive margin sequences of the Neoproterozoic ocean were polydeformed and polymetamorphosed to the biotite zone of the greenschist facies to up to granulite facies and anatexis towards the southern migmatitic core of the Central Damara Belt. Subtle relict structures and fold pattern analyses reveal the existence of an early D1 N-S shortening event, tentatively dated between ~635 Ma and ~580 Ma using published data. D1 structures were almost obliterated by pervasive and major D2 E-W coaxial shortening, related to the closure of the Kaoko-Gariep oceanic domain and subsequent formation of the NNW-striking Kaoko-Gariep Belt to the west of the study area. Early, km-scale D1 E-W trending steep folds were refolded during this D2 event, producing either Type I or Type II fold interference patterns visible from space. The D2 E-W convergence could have lasted until ~533 Ma based on published and new U-Pb ages. The final D3 NW-SE convergence in the northernmost Damara Belt produced a NE-striking deformation

  8. Identifying optimal vaccination strategies for serogroup A Neisseria meningitidis conjugate vaccine in the African meningitis belt.

    Sara Tartof

    Full Text Available OBJECTIVE: The optimal long-term vaccination strategies to provide population-level protection against serogroup A Neisseria meningitidis (MenA are unknown. We developed an age-structured mathematical model of MenA transmission, colonization, and disease in the African meningitis belt, and used this model to explore the impact of various vaccination strategies. METHODS: The model stratifies the simulated population into groups based on age, infection status, and MenA antibody levels. We defined the model parameters (such as birth and death rates, age-specific incidence rates, and age-specific duration of protection using published data and maximum likelihood estimation. We assessed the validity of the model by comparing simulated incidence of invasive MenA and prevalence of MenA carriage to observed incidence and carriage data. RESULTS: The model fit well to observed age- and season-specific prevalence of carriage (mean pseudo-R2 0.84 and incidence of invasive disease (mean R2 0.89. The model is able to reproduce the observed dynamics of MenA epidemics in the African meningitis belt, including seasonal increases in incidence, with large epidemics occurring every eight to twelve years. Following a mass vaccination campaign of all persons 1-29 years of age, the most effective modeled vaccination strategy is to conduct mass vaccination campaigns every 5 years for children 1-5 years of age. Less frequent campaigns covering broader age groups would also be effective, although somewhat less so. Introducing conjugate MenA vaccine into the EPI vaccination schedule at 9 months of age results in higher predicted incidence than periodic mass campaigns. DISCUSSION: We have developed the first mathematical model of MenA in Africa to incorporate age structures and progressively waning protection over time. Our model accurately reproduces key features of MenA epidemiology in the African meningitis belt. This model can help policy makers consider vaccine

  9. Paleoproterozoic Greenstone-Granite Belts in Northern Brazil and the Former Guyana Shield - West African Craton Province

    Ian McReath


    Full Text Available The mainly meta-volcano-sedimentary Vila Nova Group and associated granites constitute separate belts, which formpart of a large paleoproterozoic (mainly rhyacian province in the Guyana Shield of which northern Brazil forms a part, andthe West African Craton. In Brazil the southwestern Serra do Ipitinga and Serra Tumucumaque-Serra do Navio belts have noobvious geometrical extensions in the Guyanas or Venezuela, and may represent deposits formed at penecontemporaneouspassive continental margins and ocean floor spreading centres. To the Northeast the Serra Lombarda-Tartarugalzinho andOiapoque belts are continuations of Guianese belts. In the former the igneous rocks have geochemical characteristics ofsuprasubduction environments. Belts in the Guyana Shield and West African Craton have many similar features. Themegaprovince evolved in a number of stages, which may have started at about 2.3 Ga, and continued with diminished activityafter 2.11 Ga. Both major juvenile additions and (possibly minor reworking of earlier crust contributed to the growth of theprovince. The major transcurrent deformation, responsible for the present structure of the belts, probably occurred duringthe later stages of evolution of the province, but metamorphism and deformation are registered even in the oldest rocks.

  10. Northwest trending tectonic belt in the middle Yanshan Orogenic Belt of northeast Hebei Province, North China:Tectonic evolution and geochronology

    ZHANG; Changhou; WU; Ganguo; WANG; Genhou; ZHANG; Weijie


    The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults,strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation respectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt.The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement structures might be taken as one of the mechanisms of intraplate deformation and orogeny.

  11. Uranium cycle and tectono-metamorphic evolution of the Lufilian Pan-African orogenic belt (Zambia)

    Uranium is an incompatible and lithophile element, and thus more concentrated in silicate melt produced by the partial melting of the mantle related to continental crust formation. Uranium can be used as a geochemical tracer to discuss the generation and the evolution of continental crust. This thesis, focused on the Pan-African Lufilian belt in Zambia, combines structural geology, metamorphic petrology and thermos-barometry, fluid inclusions, geochemistry and geochronology in order to characterize the uranium cycle for this crustal segment. Silici-clastic and evaporitic sediments have been deposited within an intra-continental rift during the dislocation of the Rodinia super-continent during the early Neo-proterozoic. U-Pb ages on detrital zircon grains in these units indicate a dominant Paleo-proterozoic provenance. The same zircon grains show sub-chondritic εHf (between 0 and -15) and yield Hf model ages between ∼2.9 and 2.5 Ga. These data suggest that the continental crust was generated before the end of the Archean (< 2.5 Ga) associated with uranium extraction from the mantle. This old crust has been reworked by deformation and metamorphism during the Proterozoic. Uranium has been re-mobilized and reconcentrated during several orogenic cycles until the Pan-African orogeny. During this Pan-African cycle, U-Pb and REY (REE and Yttrium) signatures of uranium oxides indicate a first mineralizing event at ca. 650 Ma during the continental rifting. This event is related to late diagenesis hydrothermal processes at the basement/cover interface with the circulation of basinal brines linked to evaporites of the Roan. The second stage, dated at 530 Ma, is connected to metamorphic highly saline fluid circulations, synchronous to the metamorphic peak of the Lufilian orogeny (P=9±3 kbar; T=610±30 deg. C). These fluids are derived from the Roan evaporite dissolution. Some late uranium re-mobilizations are described during exhumation of metamorphic rocks and their

  12. Radiation belt electron precipitation and its ionospheric effects at middle latitudes

    The role of radiation belt electron precipitation into the Earth's atmosphere at middle geomagnetic latitudes is studied. First, the process of pitch angle scattering of energetic electrons in the radiation belts is modeled, and the flux angular distributions are obtained for all pitch angles, including the atmospheric bounce loss cone. This determines the angular distribution of the precipitating fluxes. Secondly, the interaction of these fluxes with the ambient atmospheric constituents is simulated, using the Fokker-Planck method; and the rate of energy deposition in the atmosphere is calculated at any given height. This gives rise to a significant rate of ion pair production in the lower ionosphere. Thirdly, the influence of this precipitation induced ionization on the structure and composition of the ionospheric D-region is modeled. Two specific classes of electron precipitation are studied; one is the quiet time ''drizzle'' occurring in the absence of geomagnetic disturbances; the second is the storm-time precipitation during the recovery phase of major geomagnetic storms with its substantial impact on the lower ionosphere. Computations are furthermore carried out for geomagnetically quiet times, and the results indicate that the electron precipitation can provide the dominant nocturnal ionization source for the D-region in a narrow belt of geomagnetic latitudes corresponding to the inner edge of the outer radiation zone (L approximately 4 to 5; Λ approximately 600 to 650) with ion pair production rates typically between 0.1 and 1 ion pair cm-3 sec-1 from about 60 to 90 kilometers at L = 5. (U.S.)

  13. A Case Study of Middle Class African American Males Taking Advanced Mathematics Classes in High School

    Jones, Zella Higginbotham


    African American males in all socioeconomic levels are underperforming in school. Many researchers have conducted studies hoping to find reasons for the underperformance. This study focused on three middle class African American males in a suburban school district. These African American male students took upper level math courses that included Algebra III, Math Analysis, AP Calculus, and AP Statistics. This study modeled the study by E. Wayne Harris. He believed students were influenced...

  14. Radiation belt electron precipitation in the upper ionosphere at middle latitudes before strong earthquakes

    Anagnostopoulos, G; Vassiliadis, E


    In this article we present examples of a wider study of space-time correlation of electron precipitation event of the Van Allen belts with the position and time of occurrence of strong (M>6.5) earthquakes. The study is based on the analysis of observations of electron bursts (EBs) with energies 70 - 2350 keV at middle geographic latitudes, which were detected by DEMETER satellite (at an altitude of ~700 km). The EBs show a relative peak-to-background increase usually < 100, they have a time duration ~0.5 - 3 min, energy spectrum with peaks moving in higher energies as the satellite moves towards the equator, and highest energy limit <~500 keV. The EBs are observed in the presence of VLF waves. The flux-time profile of the EBs varies in East Asia and Mediterranean Sea at the similar geographic latitudes, due to the differentiation of the magnitude of the earth's magnetic field. The most important result of our study is the characteristic temporal variation of electron precipitation variation which begins...

  15. Strong Lg-wave attenuation in the Middle East continental collision orogenic belt

    Zhao, Lian-Feng; Xie, Xiao-Bi


    Using Lg-wave Q tomography, we construct a broadband crustal attenuation model for the Middle East. The QLg images reveal a relationship between attenuation and geological structures. Strong attenuation is found in the continental collision orogenic belt that extends from the Turkish and Iranian plateau to the Pamir plateau. We investigate the frequency dependence of QLg in different geologic formations. The results illustrate that QLg values generally increase with increasing frequency but exhibit complex relationships both with frequency and between regions. An average QLg value between 0.2 and 2.0 Hz, QLg (0.2-2.0 Hz), may be a critical index for crustal attenuation and is used to infer the regional geology. Low-QLg anomalies are present in the eastern Turkish plateau and correlate well with low Pn-velocities and Cenozoic volcanic activity, thus indicating possible partial melting within the crust in this region. Very strong attenuation is also observed in central Iran, the Afghanistan block, and the southern Caspian Sea. This in line with the previously observed high crustal temperature, high-conductivity layers, and thick marine sediments in these areas, suggests the high Lg attenuation is caused by abnormally high tectonic and thermal activities.

  16. Teachers' Perception of African American Middle School Girls' Interest in Mathematics and Science

    Best, Bonnie M.

    Research into African American female underrepresentation in science, technology, engineering, and mathematics (STEM) fields has become an area of interest due to the fact that a majority of African American middle school females do not possess the high levels of mathematics and science knowledge because of social and cultural barriers both inside and outside school that challenge their academic success. The purpose of this qualitative interpretative phenomenological study was to explore teachers' shared, lived experiences of teaching mathematics and science to African American middle school girls. Delgado and Stefancic's critical race theory, Pratt-Clarke's critical race feminism, and Baker-Miller's relational-cultural theory were used to guide this study. Research questions focused on the perceptions and experiences of teachers' lived experiences teaching mathematics and science to African American middle school females. Criterion, purposive, and maximum variation sampling techniques were used to recruit 10 teachers who have 3 or more years' experience teaching African American middle school girls. Semistructured face-to-face interviews were the primary data collection source. First cycle and second cycle coding methods were used to support the analysis of this study. Findings suggest that there is a connection between a positive student-teacher relationship and academic success. The results of this study contribute to positive social change by providing empirical evidence policymakers and teachers can use to improve the mathematics and science instruction and practices that are needed to meet the needs of African American middle school females and reduce the underrepresentation and underachievement of African American females in mathematics and science.

  17. The Learning Environment and the Reading Achievement of Middle School African American Male Students in a Suburban School Setting

    Frazier, Nicole Denise


    The reading achievement of African American males might be impacted by a host of variables. This study was undertaken to determine if there was a difference in the culturally responsive characteristics present in the learning environment of a middle school and the reading achievement of middle school African American males. The purpose of this…

  18. Examining Parent Involvement in Reversing the Underachievement of African American Students in Middle-Class Schools

    Howard, Tyrone C.; Reynolds, Rema


    In this study, the authors examined the school experiences of middle-class African American parents and students, because they are largely overlooked in the professional literature when it comes to underachievement and parent involvement. Although No Child Left Behind (NCLB) highlights parent involvement and school accountability through the use…

  19. Van Allen Probes Mission Space Academy: Educating middle school students about Earth's mysterious radiation belts

    Butler, L.; Turney, D.; Matiella Novak, A.; Smith, D.; Simon, M.


    How's the weather in space? Why on Earth did NASA send two satellites above Earth to study radiation belts and space weather? To learn the answer to questions about NASA's Van Allen Probes mission, 450 students and their teachers from Maryland middle schools attended Space Academy events highlighting the Van Allen Probes mission. Sponsored by the Applied Physics Laboratory (APL) and Discovery Education, the events are held at the APL campus in Laurel, MD. Space Academies take students and teachers on behind-the-scenes exploration of how spacecraft are built, what they are designed to study, and introduces them to the many professionals that work together to create some of NASA's most exciting projects. Moderated by a public relations representative in the format of an official NASA press conference, the daylong event includes a student press conference with students as reporters and mission experts as panelists. Lunch with mission team members gives students a chance to ask more questions. After lunch, students don souvenir clean room suits, enjoy interactive science demonstrations, and tour APL facilities where the Van Allen Probes were built and tested before launch. Students may even have an opportunity to peek inside a clean room to view spacecraft being assembled. Prior to the event, teachers are provided with classroom activities, lesson plans, and videos developed by APL and Discovery Education to help prepare students for the featured mission. The activities are aligned to National Science Education Standards and appropriate for use in the classroom. Following their visit, student journalists are encouraged to write a short article about their field trip; selections are posted on the Space Academy web site. Designed to engage, inspire, and influence attitudes about space science and STEM careers, Space Academies provide an opportunity to attract underserved populations and emphasize that space science is for everyone. Exposing students to a diverse group of

  20. The influence of functional social support on executive functioning in middle-aged African Americans

    Sims, Regina C.; Levy, Shellie-Anne; Mwendwa, Denée T.; Callender, Clive O; Campbell, Alfonso L.


    Social support has a positive influence on cognitive functioning and buffers cognitive decline in older adults. This study examined the relations between social support and executive functioning in middle-aged adults. A community-based sample of African Americans completed the Interpersonal Support Evaluation List, a measure of functions of social support, and two measures of executive functioning, the Stroop Color Word Test and the Wisconsin Card Sorting Test (WCST). Hierarchical regression ...

  1. Estimation of Trade Protection in Middle East and North African Countries

    Maria-Angels Oliva


    This paper studies the structure and evolution of trade protection in the Middle East and North African (MENA) countries in the 1990s. MENA countries use tariffs and nontariff barriers, and tariff dispersion and nontariff barriers, as substitute protection measures. Tariff levels and tariff dispersion are complements. Excluding Tunisia, the cross-country correlation between tariff and nontariff barriers is -0.46. The correlation between tariff dispersion and nontariff barriers is -0.8. The pa...

  2. Teaching Them All: An Exploratory Mixed Methods Study of African American Students' Perceptions of Their Middle School's Culture

    Hankerson, Henry


    Research indicates school culture impacts student achievement. At Teach Them All Middle School (TTA), an achievement gap exists between African American and White students. The purpose of the current study was to examine the perceptions of African American students concerning the school culture at TTA. The research questions explored the…

  3. Comparative study on earthquake and ground based transmitter induced radiation belt electron precipitation at middle latitudes

    N. F. Sidiropoulos; Anagnostopoulos, G; Rigas, V.


    We examined (peak-to-background flux ratio p/b > 20) energetic electron bursts in the presence of VLF activity, as observed from the DEMETER satellite at low altitudes (~700 km). Our statistical analysis of measurements during two 6-month periods suggests that: (a) the powerful transmitter NWC causes the strongest effects on the inner radiation belts in comparison with other ground-based VLF transmitters, (b) the NWC transmitter was responsible for only ~1.5 % of total elect...

  4. Examining science achievement of African American females in suburban middle schools: A mixed methods study

    Topping, Kecia C.

    This dissertation examined factors that affected the science achievement of African American females in suburban middle schools. The research literature informed that African American females are facing the barriers of race, gender, socioeconomic status, and cultural learning style preferences. Nationally used measurements of science achievement such as the Standardized Achievement Test, Tenth edition (SAT-10), National Assessment for Educational Progress, and National Center for Educational Statistics showed that African American females are continuing to falter in the areas of science when compared to other ethnic groups. This study used a transformative sequential explanatory mixed methods design. In the first, quantitative, phase, the relationships among the dependent variables, science subscale SAT-10 NCE scores, yearly averages, and the independent variables, attitude toward science scores obtained from the Modified Fennema-Sherman Attitudes toward Science Scale, socioeconomics, and caregiver status were tested. The participants were 150 African American females in grades 6 through 8 in four suburban middle schools located in the Southeastern United States. The results showed a positive, significant linear relationship between the females' attitude and their science subscale SAT-10 NCE scores and a positive, significant linear relationship between the females' attitudes and their yearly averages in science. The results also confirmed that attitude was a significant predictor of science subscale SAT-10 NCE scores for these females and that attitude and socioeconomics were significant predictors of the females' yearly averages in science. In the second, qualitative, phase, nine females purposefully selected from those who had high and low attitude towards science scores on the scale in the quantitative phase were interviewed. The themes that emerged revealed seven additional factors that impacted the females' science achievement. They were usefulness of science

  5. Celiac disease in Middle Eastern and North African countries:A new burden?

    Kassem; Barada; Abbas; Bitar; Mohamad; Abdul-Razak; Mokadem; Jana; Ghazi; Hashash; Peter; Green


    Celiac disease(CD) is now recognized as a common disorder among Middle Eastern(ME) and North African(NA) populations.The aim of this review is to assess the available data regarding CD in the ME and NA and to compare this information with that of Western countries.A literature review was performed using the electronic databases PubMed and Medline(1950-2008) as search engines,and "celiac disease" was used as a Mesh term.The search was limited to ME and NA countries.The prevalence of CD in ME and NA countries...

  6. The Nubian Complex of Dhofar, Oman: an African middle stone age industry in Southern Arabia.

    Jeffrey I Rose

    Full Text Available Despite the numerous studies proposing early human population expansions from Africa into Arabia during the Late Pleistocene, no archaeological sites have yet been discovered in Arabia that resemble a specific African industry, which would indicate demographic exchange across the Red Sea. Here we report the discovery of a buried site and more than 100 new surface scatters in the Dhofar region of Oman belonging to a regionally-specific African lithic industry--the late Nubian Complex--known previously only from the northeast and Horn of Africa during Marine Isotope Stage 5, ∼128,000 to 74,000 years ago. Two optically stimulated luminescence age estimates from the open-air site of Aybut Al Auwal in Oman place the Arabian Nubian Complex at ∼106,000 years ago, providing archaeological evidence for the presence of a distinct northeast African Middle Stone Age technocomplex in southern Arabia sometime in the first half of Marine Isotope Stage 5.

  7. How African American, Middle Class Parents Learn and Enact a Racism Resistant Critical Race Achievement Ideology in Their Adolescents in Gifted and AP Classes

    Fisher, Tracey Simmons


    The purpose of this qualitative study was to examine African American, middle class parents' facilitation of an academic achievement ideology that is racism-resistant in their adolescent offspring in AP and Gifted Education classrooms. Three research questions guided the study: (1) how do African American, middle class parents come to acquire or…

  8. Introduction and Rollout of a New Group A Meningococcal Conjugate Vaccine (PsA-TT) in African Meningitis Belt Countries, 2010–2014

    Djingarey, Mamoudou H.; Diomandé, Fabien V. K.; Barry, Rodrigue; Kandolo, Denis; Shirehwa, Florence; Lingani, Clement; Novak, Ryan T.; Tevi-Benissan, Carol; Perea, William; Preziosi, Marie-Pierre; LaForce, F. Marc


    Background. A group A meningococcal conjugate vaccine (PsA-TT) was developed specifically for the African “meningitis belt” and was prequalified by the World Health Organization (WHO) in June 2010. The vaccine was first used widely in Burkina Faso, Mali, and Niger in December 2010 with great success. The remaining 23 meningitis belt countries wished to use this new vaccine. Methods. With the help of African countries, WHO developed a prioritization scheme and used or adapted existing immunization guidelines to mount PsA-TT vaccination campaigns. Vaccine requirements were harmonized with the Serum Institute of India, Ltd. Results. Burkina Faso was the first country to fully immunize its 1- to 29-year-old population in December 2010. Over the next 4 years, vaccine coverage was extended to 217 million Africans living in 15 meningitis belt countries. Conclusions. The new group A meningococcal conjugate vaccine was well received, with country coverage rates ranging from 85% to 95%. The rollout proceeded smoothly because countries at highest risk were immunized first while attention was paid to geographic contiguity to maximize herd protection. Community participation was exemplary. PMID:26553672

  9. The nature of culturally responsive pedagogy in two urban African American middle school science classrooms

    Bondima, Michelle Harris

    This ethnographic in nature study explores how two middle school science teachers who have classes populated by urban African Americans teach their students and how their students perceive their teaching. Since urban African American students continue to perform lower than desired on measures of science achievement, there is an urgent need to understand what pedagogical methodologies assist and hinder urban African American students in achieving higher levels of success in science. A pedagogical methodology that theorists posit assists subordinated school populations is culturally responsive pedagogy. Culturally responsive pedagogy is defined as a teaching methodology concerned with preparing students to question inequality, racism, and injustice. Teachers who use culturally responsive pedagogy respect the culture students bring to the class, and require that the teachers willingly do whatever is necessary to educate students (Nieto, 2000). The teacher participants were two female African Americans who were identified by their school supervisors as being highly effective with urban African American students. The researcher presented the teachers in separate case studies conducted over a data collection period of nine months. Data were collected by participant observation, interviews, and artifact collection. Data were analyzed by application of grounded theory techniques. Findings of the teachers' (and the students') beliefs about pedagogy that both assisted and hindered the students' performance in science were reported in a rich and nuanced storytelling manner based on multiple perspectives (teachers', students', and the researcher's). Pedagogical methodologies that the teachers used that assisted their students were the use of cultural metaphors and images in science and applications of motivational techniques that encouraged a nurturing relationship between the teacher and her students. Pedagogical methodologies that hindered students varied by teacher

  10. Middle-Class African American Adolescents' and Parents' Conceptions of Parental Authority and Parenting Practices: A Longitudinal Investigation.

    Smetana, Judith G.


    Examined longitudinally conceptions of parental authority and ratings of parental rules and decision-making among middle- class African American adolescents and their parents. Found that nearly all subjects affirmed parents' legitimate authority to regulate and children's obligation to comply regarding oral, conventional, prudential, friendship,…

  11. Dating Violence and Sexual Assault Prevention with African American Middle Schoolers: Does Group Gender Composition Impact Dating Violence Attitudes?

    Black, Beverly M.; Weisz, Arlene N.; Jayasundara, Dheeshana S.


    A dating violence and sexual assault prevention program was presented to 396, predominately African American, middle schoolers in two inner city schools in the United States. In one school the program was offered with a same-gender group composition; in the other school, the same program was offered with mixed-gender group composition. A…

  12. Urban African-American middle school science students: Does standards-based teaching make a difference?

    Butler Kahle, Jane; Meece, Judith; Scantlebury, Kathryn


    The current reform movement in science education promotes standards-based teaching, including the use of inquiry, problem solving, and open-ended questioning, to improve student achievement. This study examines the influence of standards-based teaching practices on the achievement of urban, African-American, middle school science students. Science classes of teachers who had participated in the professional development (n = 8) of Ohio's statewide systemic initiative (SSI) were matched with classes of teachers (n = 10) who had not participated. Data were gathered using group-administered questionnaires and achievement tests that were specifically designed for Ohio's SSI. Analyses indicate that teachers who frequently used standards-based teaching practices positively influenced urban, African-American students' science achievement and attitudes, especially for boys. Additionally, teachers' involvement in the SSI's professional development was positively related to the reported use of standards-based teaching practices in the classroom. The findings support the efficacy of high-quality professional development to change teaching practices and to enhance student learning.

  13. Large scale prediction of soil properties in the West African yam belt based on mid-infrared soil spectroscopy

    Baumann, Philipp; Lee, Juhwan; Paule Schönholzer, Laurie; Six, Johan; Frossard, Emmanuel


    Yam (Dioscorea sp.) is an important staple food in West Africa. Fertilizer applications have variable effects on yam tuber yields, and a management option solely based on application of mineral NPK fertilizers may bear the risk of increased organic matter mineralization. Therefore, innovative and sustainable nutrient management strategies need to be developed and evaluated for yam cultivation. The goal of this study was to establish a mid-infrared soil spectroscopic library and models to predict soil properties relevant to yam growth. Soils from yam fields at four different locations in Côte d'Ivoire and Burkina Faso that were representative of the West African yam belt were sampled. The project locations ranged from the humid forest zone (5.88 degrees N) to the northern Guinean savannah (11.07 degrees N). At each location, soils of 20 yam fields were sampled (0-30 cm). For the location in the humid forest zone additional 14 topsoil samples from positions that had been analyzed in the Land Degradation Surveillance Framework developed by ICRAF were included. In total, 94 soil samples were analyzed using established reference analysis protocols. Besides soils were milled and then scanned by fourier transform mid-infrared spectroscopy in the range between 400 and 4000 reciprocal cm. Using partial least squares (PLS) regression, PLS1 calibration models that included soils from the four locations were built using two thirds of the samples selected by Kennard-Stones sampling algorithm in the spectral principal component space. Models were independently validated with the remaining data set. Spectral models for total carbon, total nitrogen, total iron, total aluminum, total potassium, exchangeable calcium, and effective cation exchange capacity performed very well, which was indicated by R-squared values between 0.8 and 1.0 on both calibration and validation. For these soil properties, spectral models can be used for cost-effective, rapid, and accurate predictions

  14. Basement Characteristics and Crustal Evolution of the Copper-Gold Metallogenic Belt in the Middle and Lower Reaches of the Yangtze River: Some Isotope Constraints


    Studies of the Pb, Sr and Nd isotopic composition of Mesozoic intrusive rocks indicate that the basement of the copper-gold metallogenic belt of the middle and lower reaches of the Yangtze River has "two-layer structure" and partly has "multi-layered structure", and is inhomogeneous and shows the distinct feature of E-W provincialism. The calculated model lead ages (t1) are mostly greater than 2600 Ma, and the model neodymium ages (TDM) vary from 953 to 2276 Ma and concentrate in two time intervals: 1800- 2000 Ma and 1200- 1600 Ma. It is concluded that the basement of the MBYR is composed of the Late Archaeozoic to Middle Proterozoic metamorphic series and that the crust was initiated in the Archaean and continued to grow in the Early and Middle Proterozoic, and the proportion of new crust formed by mantle differentiation during the Late Proterozoic is low.

  15. Some characteristics of uranium distribution in granular phosphorites of Arabian-African phosphorite-bearing Province and the Middle Asia

    The comprative characteristic of uranium distribution regula-Arities in phosphorites of Arabianfrican province and the Middle Asia is given. The data on radioactivity of phosphorites of Arabian-African province are borrowed for the published papers, the laboratory U and Th determinations are partially performed. Radioactivity of the Middle Asia phosphorites is studied by field radiometric and gamma spectrometric methods. Spatial uranium distribution in granular phosphorites has been determined by the f-radiography method. At the presence of general for granular phosphorites of both regions of increased radioactivity, uranium confinement to phosphate matter and identicity of uranium distribution in them, higher uranium content of Arabian-African province is pointed out. By K and Th quatities being due to a radioactivity unit, Arabian-African phosphorites are similar to authigenous phosphorites of the Middle Asia, by uranium content Arabian phosphorites are richer than the Asian ones. Allothigenous phosphorites differ from authigenous and African ones, relative (per radioactivity unit) uranium contents in them are 2.2-1.3 times less, while thorium and potassium 5.2-6.8 times higher. This fact reflects their poverty in phosphate matter and enrichment by terrigenous sandy-argillaceous material

  16. Tectono-metamorphic evolution of the internal zone of the Pan-African Lufilian orogenic belt (Zambia): Implications for crustal reworking and syn-orogenic uranium mineralizations

    Eglinger, Aurélien; Vanderhaeghe, Olivier; André-Mayer, Anne-Sylvie; Goncalves, Philippe; Zeh, Armin; Durand, Cyril; Deloule, Etienne


    The internal zone of the Pan-African Lufilian orogenic belt (Zambia) hosts a dozen uranium occurrences mostly located within kyanite micaschists in a shear zone marking the contact between metasedimentary rocks attributed to the Katanga Neoproterozoic sedimentary sequence and migmatites coring domes developed dominantly at the expense of the pre-Neoproterozoic basement. The P-T-t-d paths reconstructed for these rocks combining field observations, microstructural analysis, metamorphic petrology and thermobarometry and geochronology indicate that they have recorded burial and exhumation during the Pan-African orogeny. Both units of the Katanga metasedimentary sequence and pre-Katanga migmatitic basement have underwent minimum peak P-T conditions of ~ 9-11 kbar and ~ 640-660 °C, dated at ca. 530 Ma by garnet-whole rock Lu-Hf isochrons. This suggests that this entire continental segment has been buried up to a depth of 40-50 km with geothermal gradients of 15-20 ° 1 during the Pan-African orogeny and the formation of the West Gondwana supercontinent. Syn-orogenic exhumation of the partially molten root of the Lufilian belt is attested by isothermal decompression under P-T conditions of ~ 6-8 kbar at ca. 530-500 Ma, witnessing an increase of the geothermal gradients to 25-30 °C·km- 1. Uranium mineralizations that consist of uraninite and brannerite took place at temperatures ranging from ~ 600 to 700 °C, and have been dated at ca. 540-530 Ma by U-Pb ages on uraninite. The main uranium deposition thus occurred at the transition from the syn-orogenic burial to the syn-orogenic exhumation stages and has been then partially transposed and locally remobilized during the post-orogenic exhumation accommodated by activation of low-angle extensional detachment.

  17. Capacity Building and Financing Oral Health in the African and Middle East Region.

    Mumghamba, E G; Joury, E; Fatusi, O; Ober-Oluoch, J; Onigbanjo, R J; Honkala, S


    Many low- and middle-income countries do not yet have policies to implement effective oral health programs. A reason is lack of human and financial resources. Gaps between resource needs and available health funding are widening. By building capacity, countries aim to improve oral health through actions by oral health care personnel and oral health care organizations and their communities. Capacity building involves achieving measurable and sustainable results in training, research, and provision of care. Actions include advancement of knowledge, attitudes and skills, expansion of support, and development of cohesiveness and partnerships. The aim of this critical review is to review existing knowledge and identify gaps and variations between and within different income levels in relation to the capacity building and financing oral health in the African and Middle East region (AMER). A second aim is to formulate research priorities and outline a research agenda for capacity building and financing to improve oral health and reduce oral health inequalities in the AMER. The article focuses on capacity building for oral health and oral health financing in the AMER of the IADR. In many communities in the AMER, there are clear and widening gaps between the dental needs and the existing capacity to meet these needs in terms of financial and human resources. Concerted efforts are required to improve access to oral health care through appropriate financing mechanisms, innovative health insurance schemes, and donor support and move toward universal oral health care coverage to reduce social inequality in the region. It is necessary to build capacity and incentivize the workforce to render evidence-based services as well as accessing funds to conduct research on equity and social determinants of oral health while promoting community engagement and a multidisciplinary approach. PMID:26101338

  18. Renewable energies in the Middle East and North African Region: can private-public partnerships address existing barriers and risks?

    Komendantova, N.


    Despite ambitious energy policy targets and available resource potentials deployment of renewable energies in the Middle East and North African (MENA) region is mainly supported by public funding. Volumes of foreign direct investment (FDI) going into the renewable energy projects in the region are minimal. Evidence suggests that existing risks for investment and how these risks are perceived b investors is keeping back private investment or makes it more costly. This paper discusses which typ...

  19. Retired African American female urban middle school science teachers' beliefs and practices

    Whitney, Frances M.

    The purpose of this paper is to give a voice to a dedicated group of professionals who unselfishly labored twenty-five plus years educating the children of America's poorest taxpaying citizens. These retired African American female urban middle school science teachers (RAAFUMSST) explain the experiences that gave them the fortitude to stay in the urban school system until their retirement. The goal is to give you a glimpse into the distractions, challenges, and victories the teachers encountered as they strove to teach science in an overcrowded, underserviced, and depressed urban school district of a major city. Most times sacrificing self for service, the participants of this study held fast to their beliefs that all of America's children, regardless of their parents' socioeconomic status, deserve a quality education. It is through individual interviews that the five retired science teachers of this project share their reflections on the events and circumstances that altered their labor of love. Critical Race Theory (CRT) serves as the theoretical frame for this study.

  20. Lifting the Voices of High-Achieving, Middle-Class, African American Students

    Brown, Stacey Marvetta


    The state of African American education is complex. Beginning in the 17th century, African Americans fought for an education that allowed them to read and write. During the 21st century, African Americans value on education extends beyond only reading and writing to using these skills and other skills to maintain strong academic and leadership…

  1. Eicosanoid Production following One Bout of Exercise in Middle-Aged African American Pre- and Stage 1 Hypertensives

    Sheara Williamson


    Full Text Available Endothelial dysfunction and a sedentary lifestyle may be involved in the development of hypertension which is proliferative among middle-aged African Americans (AA. Signaling molecules derived from the oxidation of 20-carbon fatty acid molecules known as eicosanoids influence vascular tone. The relationship between aerobic fitness and eicosanoid formation following exercise in middle-aged African American hypertensives is unknown. Purpose. To determine the relationship between aerobic capacity and eicosanoid formation after a bout of moderate-intensity exercise in middle-aged AA hypertensives. Methods. Ten sedentary hypertensive AA underwent 50 min of aerobic exercise at 65% VO2max. Urine was collected for 24 hr on two occasions, prior to testing and immediately following the bout of exercise. Urinary metabolites of prostacyclin (6-keto PGF1α and thromboxane (11-dTXB2 were measured during the day and night periods by high-performance liquid chromatography (HPLC. Results. 6-keto PGF1α levels significantly increased (=.04 following the bout of exercise compared to the control day. There was a significant relationship (=.49, <.05 between 6-keto PGF1α levels and VO2max during the exercise day. Conclusion. Based on this preliminary study, there appears to be a relationship between aerobic capacity and exercise-induced 6-keto PGF1α production in middle-aged hypertensive AAs. AAs with lower VO2max had lower 6-keto PGF1α formation.

  2. Crustal structure and geodynamics of the Middle and Lower reaches of Yangtze metallogenic belt and neighboring areas: Insights from deep seismic reflection profiling

    Lü, Qingtian; Shi, Danian; Liu, Zhendong; Zhang, Yongqian; Dong, Shuwen; Zhao, Jinhua


    A 300 km long seismic reflection profile was acquired across the Middle and Lower Reaches of the Yangtze River (MLY) metallogenic belt and its adjacent areas. The objective of the survey was to establish the deep architecture and geodynamic framework of the region. Results based on the interpretation of the deep seismic data include (1) Tan-Lu fault appears as a subvertical thrust fault or transpression fault with its deep portion dipping toward the southeast; (2) the Zhangbaling uplift is squeezed out along this fault; (3) complex upper crustal deformation structures beneath the Chuquan depression include both kink bands, thrusts, imbrication and fold structures reflecting contraction deformation, and detachment fault and normal-fault structures reflecting extensional deformation; (4) the "crocodile" reflection structure emerging beneath the Tan-Lu fault and Ningwu-Lishui volcanic basin, which represents the decoupled deformation process of the upper and lower crust associated with intra-continental subduction; (5) further to the southeast, the upper crust deformation shows a large-scale "wave-form" pattern, making crustal scale syncline and anticline; (6) the entire section of the reflection Moho is clearly discernible at depth of 30.0-34.5 km, and the Moho beneath the Middle and Lower Reaches of Yangtze River metallogenic belt is shallowest, while the Moho beneath the North China block is deeper than that beneath the Yangtze block. The Moho offsets could be seen beneath the Ningwu volcanic basin. The seismic reflection data suggest that lithosphere delamination and asthenosphere upwelling that may result from the Mesozoic intra-continental orogenesis is responsible for the formation of large scale magmatism and mineralization in the MLY metallogenic belt.

  3. Energy consumption, economic growth and CO2 emissions in Middle East and North African countries

    This article extends the recent findings of , , and by implementing recent bootstrap panel unit root tests and cointegration techniques to investigate the relationship between carbon dioxide emissions, energy consumption, and real GDP for 12 Middle East and North African Countries (MENA) over the period 1981–2005. Our results show that in the long-run energy consumption has a positive significant impact on CO2 emissions. More interestingly, we show that real GDP exhibits a quadratic relationship with CO2 emissions for the region as a whole. However, although the estimated long-run coefficients of income and its square satisfy the EKC hypothesis in most studied countries, the turning points are very low in some cases and very high in other cases, hence providing poor evidence in support of the EKC hypothesis. CO2 emission reductions per capita have been achieved in the MENA region, even while the region exhibited economic growth over the period 1981–2005. The econometric relationships derived in this paper suggest that future reductions in CO2 emissions per capita might be achieved at the same time as GDP per capita in the MENA region continues to grow. - Highlights: ► We study the links between CO2 emissions, energy consumption and GDP in MENA region. ► Energy consumption has a positive correlation with CO2 emissions. ► GDP exhibits a quadratic relationship with CO2 emissions for the region as a whole. ► However, the turning points are low in some cases and high in other cases. ► Thus, not all countries need to sacrifice economic growth to decrease CO2 emissions.

  4. Oral Health Inequalities between Rural and Urban Populations of the African and Middle East Region.

    Ogunbodede, E O; Kida, I A; Madjapa, H S; Amedari, M; Ehizele, A; Mutave, R; Sodipo, B; Temilola, S; Okoye, L


    Although there have been major improvements in oral health, with remarkable advances in the prevention and management of oral diseases, globally, inequalities persist between urban and rural communities. These inequalities exist in the distribution of oral health services, accessibility, utilization, treatment outcomes, oral health knowledge and practices, health insurance coverage, oral health-related quality of life, and prevalence of oral diseases, among others. People living in rural areas are likely to be poorer, be less health literate, have more caries, have fewer teeth, have no health insurance coverage, and have less money to spend on dental care than persons living in urban areas. Rural areas are often associated with lower education levels, which in turn have been found to be related to lower levels of health literacy and poor use of health care services. These factors have an impact on oral health care, service delivery, and research. Hence, unmet dental care remains one of the most urgent health care needs in these communities. We highlight some of the conceptual issues relating to urban-rural inequalities in oral health, especially in the African and Middle East Region (AMER). Actions to reduce oral health inequalities and ameliorate rural-urban disparity are necessary both within the health sector and the wider policy environment. Recommended actions include population-specific oral health promotion programs, measures aimed at increasing access to oral health services in rural areas, integration of oral health into existing primary health care services, and support for research aimed at informing policy on the social determinants of health. Concerted efforts must be made by all stakeholders (governments, health care workforce, organizations, and communities) to reduce disparities and improve oral health outcomes in underserved populations. PMID:26101336

  5. Paleozoic structure of Middle Tien Shan (Kyrgyzstan Central Asian Orogenic Belt): Insights on the polarity and timing of tectonic motions, subductions, and lateral correlations

    Jourdon, Anthony; Loury, Chloé; Rolland, Yann; Petit, Carole; Bellahsen, Nicolas


    The structure and Palaeozoic tectonic evolution in Kyrgyz and Chinese Tien Shan Central Asian Orogenic Belt (CAOB) are still a matter of debate. There are numerous and conflicting models about the polarity of tectonic motions in the Paleozoic, the number of continental blocks and oceanic basins involved and the timing of tectonic events. In this study we propose new maps and structural cross-sections of Middle and South Kyrgyz Tien Shan (TS). These cross-sections allow us to highlight an overall South-verging structure in the Middle TS, with a thick-skin style involving the crystalline basement. This deformation occurred during the Early Carboniferous, and is sealed by an Upper Carboniferous unconformity. We ascribe this structure to an Upper Plate deformation linked to north-dipping subduction below Middle TS. In contrast, the South TS exhibits a north-verging structure, linked to south-dipping subduction, which is evidenced by an accretionary prism, a volcanic arc, and high-pressure rocks (Loury et al., 2015), and is correlated to similar structures in the Chinese TS (e.g., Charvet et al., 2011). Based on these observations, we propose a new interpretation of the tectonic evolution of the Middle and South TS CAOB. The resulting model comprises a long-lived north-dipping subduction of the Turkestan Ocean below the Middle TS-Karazakh Platform and a short-lived south-dipping subduction of a marginal back-arc basin below the Tarim. Consequently, the South TS is interpreted as a rifted block from the Tarim. Finally, the docking of the large Tarim Craton to the CAOB corresponds to a rapid collision phase (320-300 Ma). This put an end to the long-lived Paleozoic subduction history in the CAOB. Charvet, J., Shu, L., et al., 2011. Palaeozoic tectonic evolution of the Tianshan belt, NW China. Science China Earth Sciences, 54, 166-184. Loury, C. , Rolland, Y., Guillot S., Mikolaichuk, A.V., Lanari, P., Bruguier, O., D.Bosch, 2015. Crustal-scale structure of South Tien Shan

  6. Black Moms and “White Motherhood Society”: African-American Middle-Class Mothers’ Perspectives on Work, Family and Identity

    Dow, Dawn


    African-American middle-class mothers have historically been structurally, culturally, and economically excluded from the practices related to hegemonic frameworks of mothering and parenting that have been described and critiqued by family and work life scholars. Collectively these frameworks make three theoretical assumptions: 1) mothers are principally responsible for raising children, 2) working outside of the home conflicts with being a mother and 3) middle-class mothers share beliefs ab...

  7. African Homo erectus: Old radiometric ages and young Oldowan assemblages in the middle Awash Valley, Ethiopia

    Clark, J.D.; White, T.D.; Selassie, Y.H. (Univ. of California, Berkeley, CA (United States)); Heinzelin, J. de (Institut Royal des Sciences Naturelles de Belgique, Brussels (Belgium)); Schick, K.D. (Indiana Univ., Bloomington, IN (United States)); Hart, W.K. (Miami Univ., Oxford, OH (United States)); WoldeGabriel, G. (Los Alamos National Lab., NM (United States)); Walter, R.C. (Institute of Human Origins, Berkeley, CA (United States)); Suwa, G. (Univ. of Tokyo (Japan)); Asfaw, B. (Addis Ababa (Ethiopia)) (and others)


    Fossils and artifacts recovered from the middle Awash Valley of Ethiopia's Afar depression sample the Middle Pleistocene transition from Homo erectus to Homo sapiens. Ar/Ar ages, biostratigraphy, and tephrachronology from this area indicate that the Pleistocene Bodo hominid cranium and newer specimens are approximately 0.6 million years old. Only Oldowan chopper and flake assemblages are present in the lower stratigraphic units but Acheulean bifacial artifacts are consistently prevalent and widespread in directly overlying deposits. This technological transition is related to a shift in sedimentary regime, supporting the hypothesis that Middle Pleistocene Oldowan assemblages represent a behavioral facies of the Acheulean industrial complex.

  8. Student Perceptions of Teacher Characteristics on Math Achievement for Middle School African American Students

    Clayton, Otis, Jr.


    This causal-comparative research explored how African American students' perceptions of their math teachers affected their academic performance on the Math Tennessee Comprehensive Assessment Program (TCAP) Test during 2009-2010 academic year. When considering possible measures of teacher effectiveness in K-12 education, it can be argued that…

  9. Creating a virtual community of practice to investigate legitimate peripheral participation by African American middle school girls in science activities

    Edwards, Leslie D.

    How do teenage girls develop an interest in science? What kinds of opportunities can science teachers present to female students that support their engagement with learning science? I studied one aspect of this issue by focusing on ways students could use science to enhance or gain identities that they (probably) already valued. To do that I created technology-rich activities and experiences for an after school class in science and technology for middle school girls who lived in a low socio-economic urban neighborhood. These activities and experiences were designed to create a virtual community of practice whose members used science in diverse ways. Student interest was made evident in their responses to the activities. Four conclusions emerged. (1) Opportunities to learn about the lives and work of admired African American business women interested students in learning by linking it to their middle-class aspirations and their interest in things that money and status can buy. (2) Opportunities to learn about the lives and work of African American women experts in science in a classroom context where students then practiced similar kinds of actual scientific tasks engaged students in relations of legitimate peripheral participation in a virtual and diverse community of practice focused on science which was created in the after-school classes. (3) Opportunities where students used science to show off for family, friends, and supporters of the after-school program, identities they valued, interested them enough that they engaged in long-term science and technology projects that required lots of revisions. (4) In response to the opportunities presented, new and enhanced identities developed around becoming a better student or becoming some kind of scientist.

  10. The Middle Jurassic succession in the central sector of the Pieniny Klippen Belt (Sprzycne Creek: implications for the timing of the Czorsztyn Ridge development

    Segit Tomasz


    Full Text Available In this study, we revisit the stratigraphic age and discuss sedimentary characteristics of the lower Middle Jurassic turbidite deposits (“black flysch” of the Szlachtowa Formation, as well as the under- and overlying members of the Sprzycne Creek section situated in the central sector of the Pieniny Klippen Belt (Poland. We show that the succession captures the lower Middle Jurassic marine sediments of the pre-Late Albian Magura Basin, located to the north of an ancient submarine swell (Czorsztyn Ridge. The turbidite deposits of the Szlachtowa Formation and marly shales of the Opaleniec Formation yield dinoflagellate cysts indicative of the latest Aalenian or learliest Bajocian to Early Bathonian. The character of these deposits, and their location below the overthrusted Subpieniny Nappe show that this succession does not belong to the successions of the Oravicum domain, located on the southern side of the Czorsztyn Ridge. The Szlachtowa Formation is underlain by the Skrzypny Formation, which is reported for the first time outside the Oravicum domain. It suggests that the pre-Late Albian Magura Basin came into existence not earlier than during the latest Aalenian, following the rising of the Czorsztyn Ridge. The marly shales assigned here to the Opaleniec Formation of Late Bajocian-Bathonian age and younger marly deposits of Cretaceous age were distinguished in the past as the so-called “Sprzycne beds” of Cretaceous age. However, the combination of these two rock units into a single lithostratigraphic unit is unsuitable because they represent two separated stratigraphical intervals and their contact is tectonic.

  11. Virtual industrial water usage and wastewater generation in the Middle East/North African region

    S. R. Sakhel; Geissen, S.-U.; A. Vogelpohl


    This study deals with the quantification of volumes of water usage, wastewater generation, virtual water export, and wastewater generation from export for eight export relevant industries present in the Middle East/North Africa (MENA). It shows that about 3400 million m3 of water is used per annum while around 793 million m3 of wastewater is generated from products that are meant for domestic consumption and export. The difference between volumes of water usage and ...

  12. Early-Middle Paleozoic subduction-collision history of the south-eastern Central Asian Orogenic Belt: Evidence from igneous and metasedimentary rocks of central Jilin Province, NE China

    Pei, Fu-Ping; Zhang, Ying; Wang, Zhi-Wei; Cao, Hua-Hua; Xu, Wen-Liang; Wang, Zi-Jin; Wang, Feng; Yang, Chuan


    To constrain the Early-Middle Paleozoic tectonic evolution of the south-eastern segment of the Central Asian Orogenic Belt (CAOB), we undertook zircon U-Pb dating and analyzed major and trace elements and zircon Hf isotope compositions of Late Cambrian to Middle Devonian igneous and metasedimentary rocks in central Jilin Province, NE China. LA-ICP-MS zircon U-Pb dating indicates that the Early-Middle Paleozoic magmatism in central Jilin Province can be divided into four episodes: Late Cambrian (ca. 493 Ma), Middle Ordovician (ca. 467 Ma), Late Ordovician-Early Silurian (ca. 443 Ma), and Late Silurian-Middle Devonian (425-396 Ma). The progression from subduction initiation to maturity is recorded by Late Cambrian low-K tholeiitic meta-diabase, Middle Ordovician medium-K calc-alkaline pyroxene andesite, and Late Ordovician to Early Silurian low-K tonalite, which all have subduction-related characteristics and formed in an evolving supra-subduction zone setting. Late Silurian to Middle Devonian calc-alkaline igneous rocks, with the lithological association of granodiorite, monzogranite, rhyolite, dacite, and trachydacite, show progressively increasing K2O contents from medium K to shoshonite series. Furthermore, the Early-Middle Devonian monzogranites are characterized by high K2O, Sr/Y, and [La/Yb]N values, indicating they were generated by the melting of thickened lower crust. These results suggest a transition from subduction to post-orogenic setting during the Late Silurian-Middle Devonian. Our interpretation is supported by the maximum age of molasse deposition in the Zhangjiatun member of the Xibiehe Formation. Overall, we suggest that Late Cambrian tholeiitic meta-diabase, Middle Ordovician pyroxene andesite, and Late Ordovician-Early Silurian tonalite formed above the northward-subducting and simultaneously seaward-retreating of Paleo-Asian Ocean plate. Subsequently, the northern arc collided with the North China Craton and post-orogenic extension occurred

  13. Adakitic magmatism in post-collisional setting: An example from the Early-Middle Eocene Magmatic Belt in Southern Bulgaria and Northern Greece

    Marchev, Peter; Georgiev, Stoyan; Raicheva, Raya; Peytcheva, Irena; von Quadt, Albrecht; Ovtcharova, Maria; Bonev, Nikolay


    Post-collisional (56.0-40.4 Ma) adakitic magmatism in the Rhodope Massif and the Kraishte region, including W. Srednogorie, in South Bulgaria followed the collision of the Rhodope and Pelagonian Massifs. It forms a 250 km NW trending belt which continues into the 1000 km long belt of Eocene magmatism in northern Turkey and Iran. The rocks are represented by felsic subvolcanic dykes and sills in the Kraishte and plutons in the Rhodopes. Here, we synthesize new chemical (whole-rock major and trace elements, and Sr and Nd isotopes) and LA-ICP/MS mineral and U-Pb zircon age data along with published similar data in order to constrain the genesis of this magmatism and the early Cenozoic geodynamic evolution of the central Balkan Peninsula. The rocks display typical subduction-related characteristics with enrichment in LILE and LREE and depletion in HFSE (Nb, Ta and Ti). In the Kraishte and western Srednogorie Zones these are calc-alkaline to high-K calc-alkaline rhyolites, displaying a typical adakitic signature, i.e. high La/Yb and Sr/Y ratios. The studied Rhodope Massif rocks are predominantly high-K calc-alkaline and subordinate calc-alkaline granites and granodiorites with a minor amount of tonalites. Petrographically, they are H2O- and accessory-rich (allanite, epidote, titanite, apatite) rocks, showing geochemical affinities from non-adakitic tonalites and mafic granodiorites to adakitic granodiorites and granites. Similarity of Sr and Nd isotopic compositions of the Kraishte subvolcanic and Rhodope intrusive adakitic rocks with the neighboring and coeval NW Anatolian basaltic to dacitic volcanics and plutons suggests that the most likely source for the South Bulgarian adakitic rocks is the subduction-enriched depleted lithospheric mantle. The nearby and contemporaneous East Serbian alkaline basalts are isotopically and compositionally different and, probably, originate from an OIB-like mantle source. Subsequent fractionation within an isotopically similar lower

  14. Geochemistry and Nd Sr isotopic studies of Late Mesozoic granitoids in the southeastern Hubei Province, Middle Lower Yangtze River belt, Eastern China: Petrogenesis and tectonic setting

    Xie, Guiqing; Mao, Jingwen; Li, Ruiling; Bierlein, Frank P.


    A geochemical and isotopic study was carried out for the Mesozoic Yangxin, Tieshan and Echeng granitoid batholiths in the southeastern Hubei Province, eastern China, in order to constrain their petrogenesis and tectonic setting. These granitoids dominantly consist of quartz diorite, monzonite and granite. They are characterized by SiO 2 and Na 2O compositions of between 54.6 and 76.6 wt.%, and 2.9 to 5.6 wt.%, respectively, enrichment in light rare earth elements (LREE) and large ion lithophile elements (LILE), and relative depletion in Y (concentrations ranging from 5.17 to 29.3 ppm) and Yb (0.34-2.83 ppm), with the majority of the granitoids being geochemically similar to high-SiO 2 adakites (HSA). Their initial Nd ( ɛNd = - 12.5 to - 6.1) and Sr (( 87Sr/ 86Sr) i = 0.7054-0.7085) isotopic compositions, however, distinguish them from adakites produced by partial melting of subducted slab and those produced by partial melting of the lower crust of the Yangtze Craton in the Late Mesozoic. The granitoid batholiths in the southeastern Hubei Province exhibit very low MgO ranging from 0.09 to 2.19 wt.% with an average of 0.96 wt.%, and large variations in negative to positive Eu anomalies (Eu/Eu * = 0.22-1.4), especially the Tieshan granites and Yangxin granite porphyry (Eu/Eu * = 0.22-0.73). Geochemical and Nd-Sr isotopic data demonstrate that these granitoids originated as partial melts of an enriched mantle source that experienced significant contamination of lower crust materials and fractional crystallization during magma ascent. Late Mesozoic granitoids in the southeastern Hubei Province of the Middle-Lower Yangtze River belt were dominantly emplaced in an extensional tectonic regime, in response to basaltic underplating, which was followed by lithospheric thinning during the early Cretaceous.

  15. Burden of rotavirus gastroenteritis in the Middle Eastern and North African pediatric population

    Duan Yinghui


    Full Text Available Abstract Background Rotavirus gastroenteritis (RVGE is the most common cause of severe childhood diarrhea worldwide. Objectives were to estimate the burden of RVGE among children less than five years old in the Middle East (Bahrain, Iran, Iraq, Israel, Jordan, Kuwait, Oman, Qatar, Saudi Arabia, Syria, UAE, Yemen, North Africa (Algeria, Egypt, Libya, Morocco, Tunisia and Turkey. Methods A comprehensive literature search was conducted in major databases on the epidemiology and burden of rotavirus among children less than five years old between 1999 and 2009. Data from each country was extracted and compared. Results The search identified 43 studies. RVGE was identified in 16-61% of all cases of acute gastroenteritis, with a peak in the winter. RVGE-related hospitalization rates ranged from 14% to 45%, compared to 14%-28% for non-RVGE. Annually, RVGE caused up to 112 fatalities per 100,000 in certain countries in the region. Hospitalization costs ranged from $1.8 to $4.6 million annually, depending on the country. The most recent literature available showed that G1P[8] was the most prevalent genotype combination in 8 countries (range 23%-56%. G2P[4] was most prevalent in 4 countries (26%-48%. G9P[8] and G4P[8] were also frequently detected. Conclusions RVGE is a common disease associated with significant morbidity, mortality, and economic burden. Given the variety and diverse rotavirus types in the region, use of a vaccine with broad and consistent serotype coverage would be important to help decrease the burden of RVGE in the Middle East and North Africa.

  16. Geological Fluid Mapping in the Tongling Area: Implications for the Paleozoic Submarine Hydrothermal System in the Middle-Lower Yangtze Metallogenic Belt, East China


    The Tongling area is one of the 7 ore-cluster areas in the Middle-Lower Yangtze metallogenic belt, East China, and has tectonically undergone a long-term geologic history from the late Paleozoic continental rifting, through the Middle Triassic continent-continent collision to the Jurassic-Cretaceous intracontinental tectono-magmatic activation. The Carboniferous sedimentary-exhalative processes in the area produced widespread massive sulfides with ages of 303-321 Ma, which partly formed massive pyrite-Cu deposits, but mostly provided significant sulfur and metals to the skarn Cu mineralization associated with the Yanshanian felsic intrusions.To understand the Carboniferous submarine hydrothermal system, an area of about 1046 km2 was chosen to carry out the geological fluid mapping. Associated with massive sulfide formation, footwall sequences 948 m to 1146 m thick, composed of the Lower Silurian-Upper Devonian sandstone, siltstone and thin-layered shale, were widely altered. This hydrothermal alteration is interpreted to reflect largescale hydrothermal fluid flow associated with the late Paleozoic crustal rifting and subsidence. Three hydrothermal alteration types, i.e., deep-level semiconformable silicification (S1), fracture-controlled quartz-sericite-pyrite alteration (S2-3), and upper-level sub-discordant quartz-sericite-chlorite alteration (D3), were developed to form distinct zones in the mapped area. About 50-m thick semiconformable siliclfication zones are located at ~1-km depth below massive sulfides and developed between an impermeable shale caprock (S1) and the underlying Ordovician unaltered limestone.Comparisons with modern geothermal systems suggest that the alteration zones record a sub-seafloor aquifer with the most productive hydrothermal fluid flow. Fracture-controlled quartz-sericite-pyrite alteration formed transgressive zones, which downward crosscut the semiconformable alteration zones,and upwards grade into sub-discordant alteration zones

  17. Middle east and North African oil in international relations (from 1970 to these days)

    Petroleum is not purely an economical product, its main role in world economy and its concentration in Middle East and North Africa (two third of world reserves) made influence international politics. Knowing the nature of the region, petroleum and politics make one. The politicization of oil in the region starts, first of all, with the efforts of some powers, through their companies, to dominate oil countries, which by reaction incite these countries to eliminate foreign domination and establish their national control on oil matters. The situation is changing progressively. The position of productive states got stronger with the beginning of the 1970's which permitted the use of oil, in a way relatively efficient, as an instrument of power. Consequently, the balance of power shifted deeply in the favor of producers. On this basis, the argument consists of three parts: the first puts theoretic bases - theory of economical arm - and defines geographical and historical environment of the research. The second part studies the period of force of the oil countries, from the fourth Israel-Arab war and oil embargo that followed it, to the end of the second oil slump. The third part explains the shift of power on the international scene and the relative decline of oil power for the states of the region. The analysis of impact of the oil slump in 1986 and the mini impact of the second Persian Gulf war, quickly dominated, lead to clear the actual situation and outline the viewpoint of the future. (author)

  18. Virtual industrial water usage and wastewater generation in the Middle East/North African region

    S. R. Sakhel


    Full Text Available This study deals with the quantification of volumes of water usage, wastewater generation, virtual water export, and wastewater generation from export for eight export relevant industries present in the Middle East/North Africa (MENA. It shows that about 3400 million m3 of water is used per annum while around 793 million m3 of wastewater is generated from products that are meant for domestic consumption and export. The difference between volumes of water usage and wastewater generation is due to water evaporation or injecting underground (oil wells pressure maintenance. The wastewater volume generated from production represents a population equivalent of 15.5 million in terms of wastewater quantity and 30.4 million in terms of BOD. About 409 million m3 of virtual water flows from MENA to EU27 (resulting from export of eight commodities which is equivalent to 12.1% of the water usage of those industries and Libya is the largest virtual water exporter (about 87 million m3. Crude oil and refined petroleum products represent about 89% of the total virtual water flow, fertilizers represent around 10% and 1% remaining industries. EU27 poses the greatest indirect pressure on the Kuwaiti hydrological system where the virtual water export represents about 96% of the actual renewable water resources in this country. The Kuwaiti crude oil water use in relation to domestic water withdrawal is about 89% which is highest among MENA countries. Pollution of water bodies, in terms of BOD, due to production is very relevant for crude oil, slaughterhouses, refineries, olive oil, and tanneries while pollution due to export to EU27 is most relevant for crude oil industry and olive oil mills.

  19. Virtual industrial water usage and wastewater generation in the Middle East/North African region

    Sakhel, S. R.; Geissen, S.-U.; Vogelpohl, A.


    This study deals with the quantification of volumes of water usage, wastewater generation, virtual water export, and wastewater generation from export for eight export relevant industries present in the Middle East/North Africa (MENA). It shows that about 3400 million m3 of water is used per annum while around 793 million m3 of wastewater is generated from products that are meant for domestic consumption and export. The difference between volumes of water usage and wastewater generation is due to water evaporation or injecting underground (oil wells pressure maintenance). The wastewater volume generated from production represents a population equivalent of 15.5 million in terms of wastewater quantity and 30.4 million in terms of BOD. About 409 million m3 of virtual water flows from MENA to EU27 (resulting from export of eight commodities) which is equivalent to 12.1% of the water usage of those industries and Libya is the largest virtual water exporter (about 87 million m3). Crude oil and refined petroleum products represent about 89% of the total virtual water flow, fertilizers represent around 10% and 1% remaining industries. EU27 poses the greatest indirect pressure on the Kuwaiti hydrological system where the virtual water export represents about 96% of the actual renewable water resources in this country. The Kuwaiti crude oil water use in relation to domestic water withdrawal is about 89% which is highest among MENA countries. Pollution of water bodies, in terms of BOD, due to production is very relevant for crude oil, slaughterhouses, refineries, olive oil, and tanneries while pollution due to export to EU27 is most relevant for crude oil industry and olive oil mills.

  20. Petrogenesis of the Khabr-Marvast Tectonized Ophiolite in the middle part of Nain-Baft Ophiolite belt, NW Shahrebabak, Iran

    Soltanmohammadi, A.; Rahgoshay, M.; Khalatbari-Jafari, M.


    The Late Cretaceous Khabr-Marvast tectonized Ophiolite, exposed in the middle part of Nain-Baft ophiolite belt, at the South edge of the Central Iran micro-continent. Intrusive sequence of this association comprise by: serpentinized harzburgite, isotropic gabbro, diabase sheeted dikes complex, which intruded by isolated diabase dikes, pegmatite gabbro and trondjhemite. Extrusive sequence are included: pillow lava, sheetflow and hyaloclastic breccias at passing upward. The relationship between the units of this association are tectonized.The primitive mantle-normalized multi-element plot (Sun and McDonough, 1989) indicate moderate enrichement in the LILE and show clear depletion for Nb in all samples, and depletion for Ta and Ti in most of samples. The chondrite-normalized multi-element plot indicate different enrichment of samples from LREE to HREE, and could be compare with subduction related magmatism.The variable rare earth elements patterns of the Khabr-Marvast tectonized ophiolite may reflect presence of heterogeneous source to generation of these rocks.The high Ba/Th(209-1460) ratios, low Th/Ta(0.5-1.7) and Nb/Ta(2.02-4.04) ratios in sheeted dikes and pegmatite gabbros, indicate more participant of fluids with partial melting of depleted mantle wedge in a subduction zone (Pearce et al., 2005; König et al., 2008 ). In contrast, sheetflows and isolated diabase dikes and trondjhemites have lower Ba/Th(20-170) ratios and higher Th/Ta(7.9-16.1), Nb/Ta(12.12-24) ratios which indicative of partial melting of depleted mantle and lower fluids to participating in generation of these rocks.The geological and geochemical studies suggest that the Khabr-Marvast tectonized Ophiolite had heterogeneous source and form in a supra-subduction zone system which is consistent with the model that assumes subduction of the Arabian plate under the Central Iran micro-continent.Keywords: Tectonized Ophiolite, Central Iran micro-continent, heterogeneous source, supra-subduction system.

  1. Geological, geochronological, and mineralogical constraints on the genesis of the Chengchao skarn Fe deposit, Edong ore district, Middle-Lower Yangtze River Valley metallogenic belt, eastern China

    Yao, Lei; Xie, Guiqing; Mao, Jingwen; Lü, Zhicheng; Zhao, Caisheng; Zheng, Xianwei; Ding, Ning


    The Edong ore district is located within the westernmost Middle-Lower Yangtze River Valley metallogenic belt (MLYRB), and hosts the largest concentration of skarn Fe deposits in China, although the origin of these deposits remains controversial. The Chengchao deposit is the largest skarn Fe deposit so far discovered within the MLYRB, and provides a good opportunity to address the debate surrounding the origin of these skarn Fe deposits. Here, we present geological, geochronological, and mineralogical data from the Chengchao skarn deposit and associated intrusions, and discuss the relationships between granitoids and mineralization in the Chengchao deposit. The NW-SE-striking orebodies in the study area have porphyritic quartz monzonite and/or granite footwalls, and Triassic marble or diorite hangingwalls, indicating a spatial relationship between these intrusions and Fe mineralization. Zircon U-Pb data from the granite, porphyritic quartz monzonite, diorite, and porphyritic diabase dike within the deposit show ages of 129 ± 1, 128 ± 1, 140 ± 1, and 126 ± 1 Ma, respectively. These ages and the previously reported ages on the timing of mineralization suggest that the porphyritic quartz monzonite and granite are coeval with the formation of the skarn Fe deposit. Our data confirm that the granitic rocks are temporally associated with Fe mineralization. The prograde substage of skarn development is characterized by two stages of andradite (Adr98-38Grs61-2Prp2-0Sps1-0Alm1-0) and diopside (Di95-61Hd37-5Jo3-0), including an early stage of garnet and pyroxene formation that is genetically associated with the mineralization. The early stage garnets are more andradite-rich (Adr98-50Grs49-2Prp1-0Sps1-0Alm0) than the late veinlet garnets characterized by intermediate grandite compositions (Adr67-37Grs61-31Prp2-0Sps1-0Alm1-0). The early stage pyroxenes (Di95-74Hd26-5Jo1-0) are compositionally distinct from the late stage pyroxenes (Di84-61Hd37-16Jo3-0). Compositional

  2. Signatures of solar event at middle and low latitudes in the Europe-African sector, during geomagnetic storms, October 2013

    Azzouzi, I.; Migoya-Orué, Y.; Amory Mazaudier, C.; Fleury, R.; Radicella, S. M.; Touzani, A.


    This paper presents the variability of the total electron content, VTEC, the ROTI index (proxy of the scintillation index) and the transient variations of the Earth's magnetic field associated to the impacts of solar events during October 2013. The observations are from middle and low latitudes in European African longitude sector. During October 2013, there are four solar events reaching the Earth. The two first events, on October 2 and October 8 are CME, the third event on October 14, is a jet of fast solar wind flowing from a solar coronal hole, and the last event on October 30 is a slow solar wind with southward excursions of the Bz component of the interplanetary magnetic field, associated to CME passing near the Earth. For the four events, the variation of VTEC at middle latitudes is the same and presents an increase of VTEC at the time of the impact followed by a decrease of VTEC, lasting one or several days. At low latitudes, no clear common pattern for all the events appears. For the four events the variation of the ROTI index over Africa is different showing the asymmetry between West and East Africa. For the first event, on October 2, the scintillations are not inhibited, for the second and the fourth events on October 8 and 30, the scintillations are inhibited on East Africa and for the third event (high speed solar wind stream), on October 14, the scintillations are inhibited over the whole Africa. The available data allow the full explanation of the observations of October 14, indeed, on this day, there is no post sunset increase of the virtual height h‧F2 at Ascension Island. There is no Pre Reversal Enhancement (PRE) of the eastward electric field; it is this electric field which moves up the F layer, the necessary condition for the existence of scintillation. The analysis of the variations of the Earth's magnetic field at low latitudes highlights the presence of the ionospheric disturbance dynamo on October 14, which produces a decrease of the

  3. Fission-track and K-Ar dating of pegmatite and associated rocks of Nellore Schist Belt, Andhra Pradesh: evidence of middle-to late proterozoic events

    Fission-track and K-Ar dating of minerals from pegmatitic rocks of the Nellore Schist Belt (NSB) coupled with critical appraisal of all available isotopic age data suggest episodic nature of pegmatitic activity at ca.1600 Ma.,ca.1000 Ma and 600 ± 100 Ma. The episodic pegmatitic activity in the NSB are synchronous with known phases of thermal rejuvenation in the eastern part of Cuddapah basin and in the eastern ghats mobile belt. (author). 30 refs., 2 figs., 3 tabs

  4. Y-chromosome and mtDNA genetics reveal significant contrasts in affinities of modern Middle Eastern populations with European and African populations.

    Badro, Danielle A; Douaihy, Bouchra; Haber, Marc; Youhanna, Sonia C; Salloum, Angélique; Ghassibe-Sabbagh, Michella; Johnsrud, Brian; Khazen, Georges; Matisoo-Smith, Elizabeth; Soria-Hernanz, David F; Wells, R Spencer; Tyler-Smith, Chris; Platt, Daniel E; Zalloua, Pierre A


    The Middle East was a funnel of human expansion out of Africa, a staging area for the Neolithic Agricultural Revolution, and the home to some of the earliest world empires. Post LGM expansions into the region and subsequent population movements created a striking genetic mosaic with distinct sex-based genetic differentiation. While prior studies have examined the mtDNA and Y-chromosome contrast in focal populations in the Middle East, none have undertaken a broad-spectrum survey including North and sub-Saharan Africa, Europe, and Middle Eastern populations. In this study 5,174 mtDNA and 4,658 Y-chromosome samples were investigated using PCA, MDS, mean-linkage clustering, AMOVA, and Fisher exact tests of F(ST)'s, R(ST)'s, and haplogroup frequencies. Geographic differentiation in affinities of Middle Eastern populations with Africa and Europe showed distinct contrasts between mtDNA and Y-chromosome data. Specifically, Lebanon's mtDNA shows a very strong association to Europe, while Yemen shows very strong affinity with Egypt and North and East Africa. Previous Y-chromosome results showed a Levantine coastal-inland contrast marked by J1 and J2, and a very strong North African component was evident throughout the Middle East. Neither of these patterns were observed in the mtDNA. While J2 has penetrated into Europe, the pattern of Y-chromosome diversity in Lebanon does not show the widespread affinities with Europe indicated by the mtDNA data. Lastly, while each population shows evidence of connections with expansions that now define the Middle East, Africa, and Europe, many of the populations in the Middle East show distinctive mtDNA and Y-haplogroup characteristics that indicate long standing settlement with relatively little impact from and movement into other populations. PMID:23382925

  5. Late Mesozoic bimodal volcanic rocks in the Jinniu basin, Middle-Lower Yangtze River Belt (YRB), East China: Age, petrogenesis and tectonic implications

    Xie, Guiqing; Mao, Jingwen; Xiongwei, Li; Duan, Chao; Yao, Lei


    Late Mesozoic intrusive and volcanic rocks are widespread in the southeast Hubei Province, Middle-Lower Yangtze River Belt (YRB), East China. Detailed in situ zircon U-Pb and Hf isotope, elemental and Sr-Nd-Pb isotopic data are presented in this paper for Late Mesozoic volcanic rocks from the Jinniu Basin, YRB, aiming to constrain their age, petrogenesis, and tectonic implications. The Jinniu volcanic rocks show a bimodal distribution in composition, with dominant rhyolite and dacite, and subordinate basalt and basaltic andesite. New SHRIMP and LA-ICPMS zircon U-Pb ages indicate that the volcanic rocks of three Formations in the Jinniu basin were erupted at quite a short age range of about 5 Ma during the Early Cretaceous (130-125 Ma). The mafic rocks are moderately enriched in large-ion-lithophile-elements (LILE) (e.g., Ba, Th, U, and Pb) and light rare-earth-elements (LREE), and are characterized by negative Nb, Ta, and Ti anomalies, and relatively high TiO2 (0.72-2.06%) and Nb (9.20-26.5 ppm) contents. These analyses indicate that the geochemical characteristics of the mafic rocks in the Jinniu basin are similar to worldwide Phanerozoic Nb-enriched basalt and andesites (NEBA). New in situ zircon U-Pb ages and field geological relationships demonstrate that NEBA in the southeast Hubei Province are not spatially or temporally associated with high-silica adakitic rocks, but were most likely derived from an enriched lithospheric mantle with assimilation of minor crustal materials, and then fractional crystallization during the evolution of the magma. Overall, the felsic rocks in the Jinniu basin have geochemical characteristics, and Sr-Nd-Pb signatures, and in situ zircon Hf isotopic compositions similar to those of the mafic rocks. Compared with the mafic rocks, the felsic rocks are characterized by enriched and variable concentrations of LILE and REE (e.g., Ba = 33.3-1372 ppm, Y = 11.4-33.6 ppm, YbC = 5.07-18.7), and negative Eu anomalies (δEu = 0.22-0.98), as

  6. The karyotype of the middle-African hedgehog Atelerix albiventris Wagner, 1841 and its cytotaxonomical relationships to other Erinaceinae (Insectivora: Erinaceidae).

    Hübner, R; Maddalena, T; Poduschka, W


    Like other hedgehog species investigated hitherto, also the Middle African species Atelerix albiventris has a diploid number of 48 chromosomes. However, Aethechinus and Atelerix display quite distinct cytogenetic characteristics compared to the hedgehog genera Erinaceus, Hemiechinus and Paraechinus. Individual chromosome structures and reactivities permit the recognition of similarities to the Algerian hedgehog Aethechinus algirus and indicate their close relationship. Nevertheless, the proposal by Corbet (1988) to merge the two taxa into one genus, which is contrary to Robbins and Setzer (1985) remains to be clarified by further investigations. PMID:1879689

  7. Self-reported Experiences of Discrimination and Visceral Fat in Middle-aged African-American and Caucasian Women

    Lewis, Tené T.; Kravitz, Howard M.; Janssen, Imke; Powell, Lynda H.


    The authors examined the association between self-reported experiences of discrimination and subtypes of abdominal fat (visceral, subcutaneous) in a population-based cohort of African-American and Caucasian women. Prior studies examining associations between discrimination and abdominal fat have yielded mixed results. A major limitation of this research has been the reliance on waist circumference, which may be a poor marker of visceral fat, particularly for African-American women. Participan...

  8. The Attitudes of African American Middle School Girls Toward Computer Science: Influences of Home, School, and Technology Use

    Robinson, Ashley Renee


    The number of women in computing is significantly low compared to the number of men in the discipline, with African American women making up an even smaller segment of this population. Related literature accredits this phenomenon to multiple sources, including background, stereotypes, discrimination, self-confidence, and a lack of self-efficacy or belief in one's capabilities. However, a majority of the literature fails to represent African American females in research studies. This r...

  9. Geology and geochemistry of the Middle Proterozoic Eastern Ghat mobile belt and its comparison with the lower crust of the Southern Peninsular shield

    Rao, M. V. Subba


    Two prominent rock suites constitute the lithology of the Eastern Ghat mobile belt: (1) the khondalite suite - the metapelites, and (2) the charnockite suite. Later intrusives include ultramafic sequences, anorthosites and granitic gneisses. The chief structural element in the rocks of the Eastern Ghats is a planar fabric (gneissosity), defined by the alignment of platy minerals like flattened quartz, garnet, sillimanite, graphite, etc. The parallelism between the foliation and the lithological layering is related to isoclinal folding. The major structural trend (axial plane foliation trend) observed in the belt is NE-SW. Five major tectonic events have been delineated in the belt. A boundary fault along the western margin of the Eastern Ghats, bordering the low grade terrain has been substantiated by recent gravity and the deep seismic sounding studies. Field evidence shows that the pyroxene granulites (basic granulites) post-date the khondalite suite, but are older than the charnockites as well as the granitic gneisses. Polyphase metamorphism, probably correlatable with different periods of deformation is recorded. The field relations in the Eastern Ghats point to the intense deformation of the terrain, apparently both before, during and after metamorphism.

  10. Structural setting of the Apennine-Maghrebian thrust belt

    PieroElter; MarioGrasso; MaurizioParotto; LivioVezzani


    The Apennine-Maghrebian fold-and-thrust belt devel-oped from the latest Cretaceous to Early Pleistocene at the subduction-collisional boundary between the Euro-pean and the westward-subducted Ionian and Adria plates. Large parts of the Mesozoic oceanic lithosphere were subducted during an Alpine phase from the Late Cretaceous to Middle Eocene. The chain developed through the deformation of major paleogeographic internal domains (tectono-sedimentary sequences of the Ligurian-Piedmont Ocean) and external domains (sedi-mentary sequences derived from the deformation of the continental Adria-African passive mareinL The continu-ity of the Apennine chain is abruptly interrupted in the Calabrian Arc by the extensive klippe of Kabylo-Calabrian crystalline exotic terranes, derived from deformation of the European passive margin.Major complexities (sharp deflections in the arcuate configuration of the thrust belt, out-of-sequence propagation of the thrusts) are referred to contrasting rheology and differential buoyancy of the subducted lithosphere (transitional from conti-nental to oceanic) and consequent differential roll-back of the Adria plate margin, and to competence contrasts in the Mesozoic stratigraphic sequences,where multiple décollement horizons at different stratigraphic levels may have favored significant differential shortening.From the Late Miocene, the geometry of the thrust belt was strongly modified by extensional fault-ing, volcanic activity, crustal thinning and formation of oceanic crust correlated with the development of the Tyrrhenian Basin.

  11. “一带一路”战略视域下的中非天然气合作%Sino-African Natural Gas Cooperation in the Context of One Belt and One Road Strategy

    王涛; 曹峰毓


    当前,天然气合作已成为中非合作新的重要领域。通过梳理和分析中非间天然气贸易与投资情况、中国能源进口形势、国际油气市场态势等领域的数据和文献,笔者认为,通过加强非洲天然气供应地保障、促进中非天然气贸易、提升对非天然气投资水平、鼓励中非天然气领域的经验与智力交流等手段,可以极大地拓展我国“一带一路”战略实施的广度与深度。要实现这一目标,需要我国油气企业充分把握国际能源格局转型、中国能源企业国际化、中非能源合作升温以及“一带一路”战略配套政策等带来的机遇,进一步深化中非间天然气合作力度。当然,在这一过程中,我国油气企业必须妥善应对不利的投资环境、严峻的安全局势与外部竞争形势带来的各种挑战。%At present,natural gas cooperation between China and African countries has become an important part of Sino-African cooperation. Through extensive analysis of the data and literatures about Sino-African natural gas trade and investment, the situation of China’s energy import and the trend of the international oil and gas market,this article reveals that in order to largely broaden and deepen the practice of One Belt and One Road Strategy,China should guarantee natural gas supply in Africa,promote Sino-Africa natural gas trade and natural gas investment in Africa and encourage communication of experiences and technologies of natural gas development between China and Africa. Therefore,Chinese government should seize the opportunities brought by the transformation of world energy landscape,the internationalization of Chinese energy companies, the increasingly close Sino-African energy cooperation and the support of One Belt and One Road Strategy to further strengthen Sino-African natural gas cooperation. However,the unfavorable investment environment,the severe security situation in Africa and the

  12. The Identity Status of African Americans in Middle Adolescence: A Replication and Extension of Forbes and Ashton (1998).

    Branch, Curtis W.; Boothe, Barrington


    This study is a replication and extension of the work of Forbes and Ashton (1998). Seventy-seven African American high school students completed the revised version of the Extended Objective Measure of Ego Identity Status. Most of the students were found to be in uncommitted identity statuses. Similar results were found in both ideological and…

  13. Longitudinal Effects of Family Factors on Alcohol Use among African American and White Non-Hispanic Males during Middle School

    Horton, E. Gail; Gil, Andres


    This study examined the longitudinal effects of five family factors (familism, parent derogation, parent-child communication, family alcohol problems, and family drug problems) on intensity of alcohol use among a sample of 451 African American and White non-Hispanic males from early to mid-adolescence (sixth through eighth grades). Results…

  14. Perceptions of Parenting Practices as Predictors of Aggression in a Low-Income, Urban, Predominately African American Middle School Sample

    Murray, Kantahyanee W.; Haynie, Denise L.; Howard, Donna E.; Cheng, Tina L.; Simons-Morton, Bruce


    This research examined the relation between early adolescent aggression and parenting practices in an urban, predominately African American sample. Sixth graders (N = 209) completed questionnaires about their overt and relational aggressive behaviors and perceptions of caregivers' parenting practices. Findings indicated that moderate levels of…

  15. The Relationship between Body Size and Depressed Mood: Findings from a Sample of African American Middle School Girls

    Granberg, Ellen M.; Simons, Ronald L.; Gibbons, Frederick X.; Melby, Janet Nieuwsma


    The relationship between body weight and depression among adolescent females has been the subject of considerable attention from researchers. The risk of experiencing this distress, however, is not equally distributed across members of all racial groups. African American girls are generally more satisfied with their bodies and thus may be less…

  16. Media influence on pre-middle school African Americans' perceptions toward science, mathematics, and technology courses and careers

    Waters, Sharon Campbell


    A variety of previous studies have suggested that inaccurate, stereotypical or missing media depictions of science, engineering, and technology (SET) workers and fields have contributed to a growing shortage of youth interested in pursuing careers within the scientific endeavor. However, studies on the perceptions of African American youth have not usually been the focus of such research. In this exploratory study, in-depth interviews were conducted with 34 fifth grade African American students to determine the relative influence television and film portrayals of SET workers had on these children's perceptions of roles in SET fields and careers and school coursework related to them. Framed within the theoretical perspectives of cultivation analysis and the construction of social reality, results indicated the majority of participants perceived scientists as ambiguous, possessing either mythic characteristics of the fantastic persona or they saw them as altruistically inclined figures that saved the world from disease, destruction, and decay. Television and film portrayals of SET workers were found in varying degrees and ways to shape these African American children's perceptions toward SET careers. While children exhibited self-concepts about SET workers that were sometimes idealistic, distorted, or unrealistic, most had favorable perceptions toward math and science courses in school. However, it was the absence of television and film portrayals of African Americans in SET roles that was problematic for the majority of students. Recommendations for media producers, educators, scientific research foundations, and parents were suggested to dispel some of these commonly found media stereotypes of SET workers and African Americans in these roles and their effects.

  17. Quantification of climate and vegetation from Southern African Middle Stone Age sites - an application using Late Pleistocene plant material from Sibudu, South Africa

    Bruch, A. A.; Sievers, C.; Wadley, L.


    The isolated geographical situation of South Africa makes the unraveling of various parameters that influence its regional climate in time challenging. If the South African climate does not exhibit a linear correlation with global archives as suggested by some authors then the contribution of independent local data that provides direct information on the environment at a certain place and time is crucial. Fossil plant remains provide valuable information on past environmental conditions. Although few paleobotanical data are available from Southern Africa, some sites reveal rich and diverse fossil floras, most notably, Sibudu Cave, KwaZulu-Natal, South Africa, with its numerous fruits, seeds, pollen and charcoal flora. Such plant remains not only provide information on past vegetation, but also serve as a sound base for paleoclimate quantification with the Coexistence Approach (CA). Sibudu Cave has pulses of Middle Stone Age occupation separated by hiatuses that are as long as 10 ka. Pre-Still Bay, Still Bay, Howiesons Poort, post-Howiesons Poort and late and final Middle Stone Age industries are present. Variations in vegetation and the animals preyed on through time suggest that subtle environmental changes could have occurred during MIS4 and MIS3 in the Sibudu area. Whilst always semi-forested, the region may have comprised a mosaic of uneven and changeable patches of coastal forest and savanna. These in turn might have influenced the numbers of forest versus plains animals in the area. Cultural factors could also have played a part in the faunal variability observed in Sibudu. Preliminary analyses of Sibudu Cave material confirm the potential of the CA for its application on Late Pleistocene African floras. In the future, comparison with other contemporaneous sites will help quantify spatial differences in the climate of the Late Pleistocene in South Africa, and may answer if environmental changes effected the cultural development from Still Bay to late MSA

  18. Science self-efficacy of African American middle school students: Relationship to motivation self-beliefs, achievement, gender, and gender orientation

    Britner, Shari Lynn

    Motivation researchers have established that students' self-efficacy beliefs, the confidence they have in their academic capabilities, are related to academic outcomes. Self-efficacy has been amply researched in mathematics and language arts and nearly exclusively with White students. African American students and the area of science have each received scant attention. Typically, gender differences favor boys in mathematics and girls in language arts. Researchers have also found that these differences may be a function of gender orientation beliefs. The purpose of this study was to extend findings in science self-efficacy and to African American middle school students. I sought to determine whether self-efficacy assessed at differing levels of specificity (lab skills versus science grades) would each predict science achievement assessed at corresponding levels, to discover whether mean scores in academic motivation and achievement would differ by gender, and to determine whether these differences are a function of gender orientation (N = 268). Science grade self-efficacy was positively associated with the grades obtained by boys and by girls. For girls, grades were also associated positively with science self-concept and negatively with value of science. For reasons resulting from problematic instructional practices, lab skills self-efficacy was not associated with lab grades. Girls reported stronger science self-efficacy and received higher grades in science class. Gender orientation beliefs did not account for these differences, but masculinity and femininity were each associated with science grade self-efficacy, suggesting that androgyny is an adaptive orientation for the science self-efficacy beliefs of African American students. Findings are interpreted within the framework of A. Bandura's (1986) social cognitive theory.

  19. Great Belt

    Sørensen, Carsten S.; Kristensen, Per S.; Erichsen, Lars

    This paper describes aspects of the soil investigations and geotechnical evaluations for the foundation design of the 6.6 km long Great Belt West Bridge. The gravity foundations rest predominantly on glacial tills and pre-quaternary limestone. Special investigations for assessment of the soil pro...... properties for ship impact and ice loading are described briefly, and first experiences from settlement monitoring of the structure during erection are presented....

  20. Perceptions of Parenting Practices as Predictors of Aggression in a Low-Income, Urban, Predominately African American Middle School Sample

    Murray, Kantahyanee W.; Haynie, Denise L.; Howard, Donna E.; Tina L. Cheng; SIMONS-MORTON, BRUCE


    This research examined the relation between early adolescent aggression and parenting practices in an urban, predominately African American sample. Sixth graders (N = 209) completed questionnaires about their overt and relational aggressive behaviors and perceptions of caregivers’ parenting practices. Findings indicated that moderate levels of parental expectations for peaceful solutions at Time 1 were associated with a lower likelihood of overt aggression at Time 2. Furthermore, findings sug...

  1. BRCA Genetic Screening in Middle Eastern and North African: Mutational Spectrum and Founder BRCA1 Mutation (c.798_799delTT in North African

    Abdelilah Laraqui


    Full Text Available Background. The contribution of BRCA1 mutations to both hereditary and sporadic breast and ovarian cancer (HBOC has not yet been thoroughly investigated in MENA. Methods. To establish the knowledge about BRCA1 mutations and their correlation with the clinical aspect in diagnosed cases of HBOC in MENA populations. A systematic review of studies examining BRCA1 in BC women in Cyprus, Jordan, Egypt, Lebanon, Morocco, Algeria, and Tunisia was conducted. Results. Thirteen relevant references were identified, including ten studies which performed DNA sequencing of all BRCA1 exons. For the latter, 31 mutations were detected in 57 of the 547 patients ascertained. Familial history of BC was present in 388 (71% patients, of whom 50 were mutation carriers. c.798_799delTT was identified in 11 North African families, accounting for 22% of total identified BRCA1 mutations, suggesting a founder allele. A broad spectrum of other mutations including c.68_69delAG, c.181T>G, c.5095C>T, and c.5266dupC, as well as sequence of unclassified variants and polymorphisms, was also detected. Conclusion. The knowledge of genetic structure of BRCA1 in MENA should contribute to the assessment of the necessity of preventive programs for mutation carriers and clinical management. The high prevalence of BC and the presence of frequent mutations of the BRCA1 gene emphasize the need for improving screening programs and individual testing/counseling.

  2. 中国东北~500Ma泛非期孔兹岩带的确定及其意义%Confirming of the Heilongjiang-500Ma Pan-African khondalite belt and its tectonic implications

    周建波; 张兴洲; Simon A WILDE; 郑常青


    东北地区的变质基底,如佳木斯地块的麻山群、兴安地块的兴华渡口群等岩石组合是以(含石墨)大理岩、夕线石榴片麻岩、斜长角闪岩等为主要标志的孔兹岩系.在额尔古纳、兴安和佳木斯-兴凯地块的夕线石榴片麻岩分别得到锆石U-Pb 年铃,证明这些高级变质岩的原岩年龄以新元古代(600~850Ma)为主,变质年龄为~500Ma,因此东北地区的变质基底记录了从Rodinia到Gondwana大陆的聚合与离散的过程.泛非期高级变质岩及其同期岩浆岩在额尔古纳、兴安、松辽、佳木斯和兴凯地块等断续分布,总体出露范围>1300km,并沿虎头、鸡西、萝北、兴华渡口和漠河一线总体北西向沿黑龙江断续分布,因此我们命名为"中国东北泛非期孔兹岩带"."中国东北泛非期孔兹岩带"的提出和进一步研究,对深入探讨东北地区各地块基底组成的异同性以及陆块聚合的过程,以及东北地区的构造演化历史及其在Gondwana大陆重建中的位!都具有重要的科学意义.%The basement rocks in NE China, including Mushan Croup in Jiamusi Block, Xinghuadukou Group in the Xing' an Block, constitute a khondalitic sequence of sillimanite- and garnet-bearing gneisses, homblende-plagioclase gneiss and felsic paragneisses. Zircon U-Pb dating of the garnet-sillimanite gneiss samples from Erguna, Xing' an and Khanka blocks indicates high-grade metamorphism occurred at ~500Ma, where several detrital zircon grains whose ages extend between 600Ma to 850Ma The Pan-African high-grade metamorphism with magmatism events were obtained from all the blocks in NE China, including the Erguna, Xing' an, Songliao and Jiamusi-Khanka blocks, establish a over 1300km Pan-African khondalite belt in NE China, named here the ' Northeast China Khondalite Belt'. The results from this study provide new idea for researching the tectonic affinity and plate evolution in the NE China.

  3. Enriched asthenosphere melting beneath the nascent North African margin: trace element and Nd isotope evidence in middle-late Triassic alkali basalts from central Sicily (Italy)

    Cirrincione, Rosolino; Fiannacca, Patrizia; Lustrino, Michele; Romano, Vanessa; Tranchina, Annunziata; Villa, Igor M.


    During the dismembering of the Pangea supercontinent, middle-late Triassic sub-volcanic alkaline rocks were emplaced in central Sicily. These rocks have an alkali basaltic composition and show OIB-like incompatible element patterns in primitive mantle-normalized diagrams (e.g., enrichments in HFSE and LREE coupled with high HFSE/LILE ratios), as well as slightly positive \\varepsilon_{Nd} values. Only subtle effects of crustal contamination at shallow depths emerge from geochemical data. These characteristics are very different compared with the Permian calcalkaline magmas from elsewhere in SW Europe still carrying the geochemical signature of modifications related to the Variscan orogeny. The mineralogical, geochemical and isotopic compositions of the investigated samples from central Sicily are also different from the coeval shoshonitic volcano-plutonic formations of Southern Alps (Dolomites). The incompatible element composition and Nd isotopic ratios are consistent with low-degree partial melting of a moderately depleted asthenospheric mantle source, with a negligible involvement of the thinned continental crust. The studied alkaline basalts represent the only known evidence of a segment of the Triassic rift system associated with early Pangea breakup in central Sicily. The close similarity of the central Sicily Triassic alkali basalts with coeval basalts emplaced along former orogenic sutures across the peri-Mediterranean area suggests a common origin related, at least partly, to asthenospheric passive upwelling following the tectonic collapse of the Variscan Belt. These rocks provide new constraints on the spatial-temporal distribution, magma source evolution and geodynamic meaning of the widespread Permo-Triassic basic magmatism developed after the end of the Variscan Orogeny in southwestern Europe.

  4. "Give a Brotha a Break!": The Experiences and Dilemmas of Middle-Class African American Male Students in White Suburban Schools

    Gordon, Beverly M.


    Background/Context: Today, in the era of the first African American president, approximately one third of all African Americans live in suburban communities, and their children are attending suburban schools. Although most research on the education of African American students, particularly males, focuses on their plight in urban schooling, what…

  5. Belt attachment and system

    Schneider, Abraham D.; Davidson, Erick M.


    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  6. Comparison of the reorganisations of BP and Shell and possible opportunities for Middle East and North African Oil companies

    A critical analysis is provided of the recent reorganisations of the downstream and petrochemical activities of BP and Shell. BP (or BP Amoco including Arco) and Shell are preparing for the next decade anticipating the environment and changing the companies to maximise their profitability in that environment. For the oil producing countries of the Middle East and North Africa (MENA), there are lessons to be learned both from the forecasts which BP Amoco and Shell are making and from the way these companies intend to operate. BP Amoco's view of oil refining is that the surplus capacity is endemic; Shell's view is that it is transient. BP Amoco will market oil products selectively across the world; Shell is still intent on a global approach. Both BP Amoco and Shell will minimise their wholesaling activities in the retail market and expand their merchandising with ever better quality sites. In the petrochemicals sector, the companies are taking similar actions, ie concentrating on positions of strength and selling business activities with low market shares or poor profitability. Petrochemical sites will be favoured when they have access to company produced hydrocarbon feedstocks. From the analysis, it is suggested that MENA oil companies will need to consider carefully the timing of any new refinery building. The reorganisation of the major OECD-based oil companies should offer opportunities for MENA companies to secure outlets for LPG and condensates, to form marketing alliances in OECD markets and to become involved in OECD-based petrochemical businesses

  7. Comparison of the reorganisations of BP and Shell and possible opportunities for Middle East and North African Oil companies

    Jenkins, Gilbert


    A critical analysis is provided of the recent reorganisations of the downstream and petrochemical activities of BP and Shell. BP (or BP Amoco including Arco) and Shell are preparing for the next decade anticipating the environment and changing the companies to maximise their profitability in that environment. For the oil producing countries of the Middle East and North Africa (MENA), there are lessons to be learned both from the forecasts which BP Amoco and Shell are making and from the way these companies intend to operate. BP Amoco's view of oil refining is that the surplus capacity is endemic; Shell's view is that it is transient. BP Amoco will market oil products selectively across the world; Shell is still intent on a global approach. Both BP Amoco and Shell will minimise their wholesaling activities in the retail market and expand their merchandising with ever better quality sites. In the petrochemicals sector, the companies are taking similar actions, ie concentrating on positions of strength and selling business activities with low market shares or poor profitability. Petrochemical sites will be favoured when they have access to company produced hydrocarbon feedstocks. From the analysis, it is suggested that MENA oil companies will need to consider carefully the timing of any new refinery building. The reorganisation of the major OECD-based oil companies should offer opportunities for MENA companies to secure outlets for LPG and condensates, to form marketing alliances in OECD markets and to become involved in OECD-based petrochemical businesses.

  8. Structural and lithological controls of gold-bearing veins associated with the Brasiliano-Pan African Orogeny: An example from the Buracão Area, Araí Group (Brasília Fold Belt, Brazil)

    Pires, Gustavo Luiz Campos; Bongiolo, Everton Marques; Renac, Christophe; Nascimento, Débora Barros; Prado, Maurício


    The Buracão area, Central Brazil, comprises a group of structurally-controlled vein-type gold prospects, hosted in the metasedimentary Traíras Fm. of the Araí Group. This group records all tectonic stages of the Statherian taphrogenesis in Central Brazil and represents part of the Brasília Fold Belt (BFB) developed during the Neoproterozoic Brasiliano Orogeny. Three lithostratigraphic units were identified at the study area: two phyllitic and one composed of intercalation of quartzite and carbonaceous/sericite phyllites that hosted the Au mineralized vein systems. These units were metamorphosed to the biotite zone, greenschist facies. The high-grade mineralization (up to 31 g/t) occurs as subvertical zoned or massive veins with quartz, white mica, Fe-sulfides and Fe-oxides oriented in four main directions (i.e. N50°E; N°20E; N-S and E-W). Two deformational phases, each subdivided in two stages (D1a, D1b, D2a and D2b) were recognized in the study area. These deformational phases comprise different sets of structures, such as foliations, folds, faults, fractures and veins that represent regional deformational events on subordinated scale. The D1a and D1b stages represent the regional N-S trending thrust fronts and propagation folding developed during the evolution of W-E shortening, respectively. The D2a and D2b were correlated to the development and reactivation of regional-scale N- and NE-trending transpressive shear systems at different crustal levels, respectively. The gold-bearing quartz veins were developed during D2a stage as a complex shear fracture set according to a Riedel system, representing subordinated structures of the regional transpressive system. The structurally-controlled gold occurrences of the Buracão area is an example of orogenic vein-type gold mineralization developed during the Brasiliano-Pan African Orogeny at the BFB in Central Brazil. Our work suggests that this poorly studied part of BFB has good potential for additional high

  9. Geochemical characteristics of the Shujiadian Cu deposit related intrusion in Tongling: Petrogenesis and implications for the formation of porphyry Cu systems in the Middle-Lower Yangtze River Valley metallogenic belt, eastern China

    Wang, Shiwei; Zhou, Taofa; Yuan, Feng; Fan, Yu; Cooke, David R.; Zhang, Lejun; Fu, Bin; White, Noel C.


    Porphyry Cu deposits can form in intracontinental or post-collision settings; however, both the genesis of fertile magmas and the mechanism of metal enrichment remain controversial. The Shujiadian porphyry Cu deposit is located in the Tongling area of the Middle-Lower Yangtze River Valley metallogenic belt. It is hosted by the Shujiadian complex, which mainly consists of quartz diorite porphyry (143.7 ± 1.7 Ma) and pyroxene diorite (139.8 ± 1.6 Ma). They both belong to the calc-alkaline series, with enrichment in large-ion lithophile elements (LILE) and light rare earth elements (LREE), depletion in high field-strength elements (HFSE) and heavy rare earth elements (HREE), and slightly negative Eu anomalies. Both quartz diorite porphyry and pyroxene diorite have geochemical affinities with adakite, and their low MgO (1.5-3.7 wt%), and Ni (3.7-6.9 ppm), Cr (2.0-44 ppm), and Th/Ce contents (0.06-0.11) indicate that the intrusive rocks have some characteristics of adakite-like rocks derived from thickened lower crust and melts from metabasaltic rocks and eclogites. Plagioclases from the quartz diorite porphyry are andesine (An value = 31.8-40.5) and from the pyroxene diorite are felsic albite and oligoclase with large-scale zones and variable An value (An value = 8.9-18.3), Fe and Sr contents, which indicate that mixing of mafic and felsic magma may have occurred in the shallow magma chamber. Compared to the barren quartz diorite porphyry, relatively lower SiO2 contents (49.5-55.2 wt.%), higher εNd(t) values (- 7.4 to - 6.9), εHf(t) values (- 11.0 to - 9.1) compositions, Ti-in-zircon temperatures (714-785 °C), and variations of HREE contents of the mineralization-related pyroxene diorite suggest mixing with high-temperature mafic magma. Calculated Ce4 +/Ce3 + values of pyroxene diorite plot between the Ni-NiO buffer (NNO) and magnetite-hematite buffer (MH), and barren quartz diorite porphyry samples plot below the Ni-NiO buffer (NNO). Geochemical features of

  10. Geochronological, geochemical and mineralogical constraints of emplacement depth of TTG suite from the Sinassi Batholith in the Central African Fold Belt (CAFB) of northern Cameroon: Implications for tectonomagmatic evolution

    Houketchang Bouyo, M.; Penaye, J.; Njel, U. O.; Moussango, A. P. I.; Sep, J. P. N.; Nyama, B. A.; Wassouo, W. J.; Abaté, J. M. E.; Yaya, F.; Mahamat, A.; Ye, Hao; Wu, Fei


    The Sinassi Batholith in the Central African Fold Belt (CAFB) of northern Cameroon represents the largest volume of plutonic rocks or granitoids massif of the Western Cameroonian Domain. It is made up dominantly of tonalite-trondhjemite-granodiorite (TTG) suite and lesser granite which are locally more or less deformed, and composed of varying proportions of quartz, plagioclase, K-feldspar, biotite, hornblende, sphene, magnetite, apatite and zircon. Major and trace element compositions of fifteen rock samples of granitoids (Djourdé granodiorite, Sinassi quartz diorite and orthogneisses groups) indicate that investigated rocks from the Sinassi Batholith are characterized by medium- to high-K calc-alkaline affinity and metaluminous I-type signature. In addition, their chondrite- and primitive mantle-normalized trace element patterns are strongly fractionated ((La/Yb)N = 2.96-61.40) and show respectively enrichment in LREE relative to HREE and enrichment in LILE compared to HFSE with moderate to slight negative Nb-Ta, Ti and Eu anomalies consistent with a continental magmatic arc setting related to a subduction zone. Geothermobarometric calculations using hornblende-plagioclase thermometry and aluminum-in-hornblende barometry on eleven rock samples indicate that plutons from Sinassi Batholith were emplaced at average temperatures and pressures ranging between 698 and 720 °C and 4.06-5.82 kbar (Djourdé granitoids), 698-728 °C and 4.04-5.34 kbar (Sinassi granitoids) and 667-670 and 4.23-4.76 kbar (orthogneisses group) respectively. The average emplacement depths estimates for the investigated granitoids is constrained at ca 16-18 km, indicating that at least 16 km of crustal rocks of the Sinassi Batholith must have been eroded or uplifted at approximately exhumation rates of 0.08-0.10 mm/year. Regardless of their Th/U ratios, geochronological results highlight three main events characterizing the Neoproterozoic tectonomagmatic evolution within the Sinassi Batholith

  11. Compilation of the GSHAP regional seismic hazard for Europe, Africa and the Middle East

    D. Mayer-Rosa


    Full Text Available The seismic hazard map of the larger Europe-Africa-Middle East region has been generated as part of the global GSHAP hazard map. The hazard, expressing Peak Ground Acceleration (PGA expected at 10% probability of exceedance in 50 years, is obtained by combining the results of 16 independent regional and national projects; among these is the hazard assessment for Libya and for the wide sub-Saharan Western African region, specifically produced for this regional compilation and here discussed to some length. Features of enhanced seismic hazard are observed along the African rift zone and in the Alpine-Himalayan belt, where there is a general eastward increase in hazard with peak levels in Greece, Turkey, Caucasus and Iran.

  12. Riding the belt

    Potts, A.


    Recent developments in conveyor systems have focused on accessories rather than the belt itself. Radio frequency identification (RFID) is a technology using transponders embedded in conveyor belts and this is the latest development at the German firm Contitech. The system described in the articles developed with Moers, features transponders for cooling, controlling and monitoring conveyor belts. Other developments mentioned include a JOKI drum motor featuring a fully integrated gearbox and electric motor enclosed in a steel shell, from Interoll; a new scraper cleaning system from Hosch, new steel cord belting from Fenner, a conveying system for Schleenhain lignite opencast mine by FAM Foerdelantigen Magdeburg; new bearings from Nadella (the sales arm of Intersoll-Rand), an anti-shock belt transfer table from Rosta and new caliper disc brakes from GE Industrial.

  13. Y-Chromosome and mtDNA Genetics Reveal Significant Contrasts in Affinities of Modern Middle Eastern Populations with European and African Populations

    Badro, Danielle A.; Haber, Marc; Soria-Hernanz, David F


    The Middle East was a funnel of human expansion out of Africa, a staging area for the Neolithic Agricultural Revolution, and the home to some of the earliest world empires. Post LGM expansions into the region and subsequent population movements created a striking genetic mosaic with distinct sex-based genetic differentiation. While prior studies have examined the mtDNA and Y-chromosome contrast in focal populations in the Middle East, none have undertaken a broad-spectrum survey including Nor...


    刘晓春; 赵越; 胡健民; 刘小汉; 曲玮


    The Grove Mountains, 400 km south of the Chinese Zhongshan Station, are an inland continuation of the Prydz Belt, East Antarctica. The basement terrane of the Grove Mountains consists of voluminous mafic-felsic intrusives of ca. 920-910 Ma and a small amount of Mesoproterozoic sedimentary rock. This terrane only experienced a single Pan-African (ca. 570-500 Ma) tectonometamorphic cycle and is therefore a typical Pan-African metamorphic terrane in the Prydz Belt. The Pan-African high-grade metamorphism may have reached peak pressure-temperature (P-T) conditions of 1. 18-1.40 GPa and 770-840℃ , rather than low-to medium-pressure granulite facies as previously thought. This peak metamorphism was then followed by a near-isothermal decompression of about 0. 6 GPa. Numerous A-type charnockites and granites intruded in the metamorphic terrane during syn- to post-orogenic episodes, which resulted in a late near-isobaric cooling of the terrane. These granitoids were probably generated by partial melting of the underplating materials (alkaline basaltic rocks) derived from a long-term enriched subcontinental lithospheric mantle. Coupled with available data from other localities, we infer that the Prydz Belt developed on Archean-Grenvillian basement terranes. Subsequently, these basement terranes and Neoproterozoic cover sequences may have suffered from the same Pan-African orogenic event. The crust of the Prydz Belt was thickened to around 40-50 km, followed by about 20 km of exhumation during the Pan-African orogenesis. Accordingly, the Prydz Belt should represent a Pan-African collisional zone as a consequence of the East Gondwana assembly.%距中国中山站以南约400 km的格罗夫山是普里兹造山带向南极内陆的延伸部分,其基底地体由约在920-910 Ma期间侵入的镁铁质-长英质火成岩和少量中元古代的沉积岩构成,这些岩石仅在泛非期(约570-500 Ma)经历了单相变质—构造旋回,因此是一个典型的泛非期变质

  15. Attachment and health care utilization among middle-aged and older African-descent men: dismissiveness predicts less frequent digital rectal examination and prostate-specific antigen screening.

    Consedine, Nathan S; Tuck, Natalie L; Fiori, Katherine L


    Although health care utilization occurs in interpersonal contexts, little is known regarding how interpersonal preferences or styles among patients may be relevant. A small body of work has identified links between attachment-a dispositional style of relating to others-and patterns of health care use. The current report examined how attachment characteristics predicted the frequency of digital rectal exam and prostate-specific antigen testing in a sample of African-descent men. Four hundred and fourteen African-descent men aged 45 to 70 years completed measures of prostate screening and attachment, together with measures of traditional predictors of screening (demographics, insurance, family history, physician variables, knowledge, perceived risk, and accessibility). Consistent with predictions, dismissiveness-the most common relational style among older men-predicted less frequent prostate-specific antigen testing and digital rectal examination. However, attachment security-a comfort with intimate relationships-also predicted lower screening frequency. Identifying the interpersonal characteristics predicting screening may help identify men at risk of suboptimal health care use and guide the development of interventions suited to the normative relational preferences of current cohorts of older, African-descent men. PMID:23355546

  16. "Get up off that Thing": African American Middle School Students Respond to Literature to Develop a Framework for Understanding Social Action

    Tyson, Cynthia A.


    The use of children's literature in urban social studies classrooms to facilitate students' engagement in literate behaviors and simultaneously develop a framework for understanding social action is an under-researched area. This paper discusses the use of literature for children and young adults in an urban middle school language arts and social…

  17. Dynamic characteristics of conveyor belts

    HOU You-fu; MENG Qing-rui


    The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dynamic elastic modulus, viscous damping and theological constants of the belt were measured. Several properties were studied as a function of the tensile loading on the belt. These included longitudinal vibration, the natural vibration frequency in the transverse direction and the response to an impulse excitation. Vibration response was observed under several different excitation frequencies. Most of these properties have not been tested previously under conditions appropriate for the ISO/DP9856 standard. Two types of belt were tested, a steel reinforced belt and a fabric reinforced belt. The test equipment was built to provide data appropriate for designing belt conveyors. It was observed that the stress wave propagation speed increased with tensile load and that tensile load was the main factor influencing longitudinal vibrations.

  18. The JET belt limiter

    A limiter with an effective area in contact with the plasma of about 16 m2 is presently being manufactured for installation in 1987. This belt limiter consists of two toroidal rings located above and below the equatorial plane of the vacuum vessel. Each of the two rings comprises a structure with water cooling pipes and fins welded to the pipes. The limiter material in contact with the plasma (graphite or beryllium) is inserted between fins in the form of tiles. The belt limiter is designed to handle up to 40 MW of total power at flux densities of 3 - 5 MW/m2 for 10 s and to permit rapid exchange of different limiter materials. The design and manufacture of the belt limiter and the results of thermomechanical analysis for different edge properties, power levels and shot repetition rates, are reported. (author)

  19. The jet belt limiter

    A limiter with an effective area in contact with the plasma of about 16 m/sup 2/ is presently being manufactured for installation in 1987. This belt limiter consists of two toroidal rings located above and below the equatorial plane of the vacuum vessel. Each of the two rings comprises a structure with water cooling pipes and fins welded to the pipes. The limiter material in contact with the plasma (graphite or beryllium) is inserted between fins in the form of tiles. The belt limiter is designed to handle up to 40 MW of total power at flux densities of 3 - 5 MW/m/sup 2/ for 10 s and to permit rapid exchange of different limiter materials. This paper describes the design and manufacture of the belt limiter and the results of thermomechanical analysis for different edge properties, power levels and shot repetition rates

  20. Learning to "see" sound: An investigation into the intellectual and linguistic resources that urban middle school African American boys utilize in the practice of representing sound transmission

    Wright, Christopher G.


    This research examines the intellectual and linguistic resources that a group of African American boys brought to the study of the science of sound and the practice of representation. By taking a resource-rich view of the boys' linguistic and representational practices, my objective is to investigate children's abilities in producing, using, critiquing, and modifying representations. Specifically, this research looks to explore and identify the varieties of resources that African American boys utilize in developing scientific understanding. Using transcripts from group sessions, as well as the drawings produced during these sessions, I utilized a combination of discourse analysis to explore the boys' linguistic interactions during the critique of drawings with a focus on the boys' manipulation of line segments in order to explore their representational competencies. Analysis of the transcripts and the boys' drawings revealed several important findings. First, elements of Signifying were instrumental in the group's collective exploration of each other's drawings, and the ideas of sound transmission being represented in the drawings. Thus, I found that the boys' use of Signifying was key to their engagement win the practice of critique. Second, the boys' ideas regarding sound transmission were not fixed, stable misconceptions that could be "fixed" through instruction. Instead, I believe that their explanations and drawings were generated from a web of ideas regarding sound transmission. Lastly, the boys exhibited a form of meta-representational competency that included the production, modification, and manipulation of notations used to represent sound transmission. Despite this competency, the negotiation process necessary in constructing meaning of a drawing highlighted the complexities in developing a conventional understanding or meaning for representations. Additional research is necessary for exploring the intellectual and lingustic resources that children from

  1. Self-reported safety belt use among emergency department patients in Boston, Massachusetts

    Mitchell Patricia


    Full Text Available Abstract Background Safety belt use is 80% nationally, yet only 63% in Massachusetts. Safety belt use among potentially at-risk groups in Boston is unknown. We sought to assess the prevalence and correlates of belt non-use among emergency department (ED patients in Boston. Methods A cross-sectional survey with systematic sampling was conducted on non-urgent ED patients age ≥18. A closed-ended survey was administered by interview. Safety belt use was defined via two methods: a single-item and a multiple-item measure of safety belt use. Each was scored using a 5-point frequency scale. Responses were used to categorize safety belt use as 'always' or less than 'always'. Outcome for multivariate logistic regression analysis was safety belt use less than 'always'. Results Of 478 patients approached, 381 (80% participated. Participants were 48% female, 48% African-American, 40% White, median age 39. Among participants, 250 (66% had been in a car crash; 234 (61% had a valid driver's license, and 42 (11% had been ticketed for belt non-use. Using two different survey measures, a single-item and a multiple-item measure, safety belt use 'always' was 51% and 36% respectively. According to separate regression models, factors associated with belt non-use included male gender, alcohol consumption >5 drinks in one episode, riding with others that drink and drive, ever receiving a citation for belt non-use, believing that safety belt use is 'uncomfortable', and that 'I just forget', while 'It's my usual habit' was protective. Conclusion ED patients at an urban hospital in Boston have considerably lower self-reported safety belt use than state or national estimates. An ED-based intervention to increase safety belt use among this hard-to-reach population warrants consideration.

  2. Post-Variscan evolution of the Anti-Atlas belt of Morocco constrained from low-temperature geochronology

    Gouiza, M.; Charton, R.; Bertotti, G.; Andriessen, P.; Storms, J. E. A.


    The Anti-Atlas belt of Morocco extends ENE-WSW, over more than 600 km, from the Atlantic margin in the west to the interior of the African plate in the east. It exhibits Precambrian rocks outcropping as basement inliers and surrounded by marine Ediacaran-Cambrian sequences around the axis of the mountain range. The belt, which has for a long time been interpreted as of Variscan age, is now revealed to have experienced major vertical movements through Mesozoic and Cenozoic times. Thereby, the Anti-Atlas domain appears to be affected by two episodes of exhumation separated by an episode of subsidence. The initial episode occurred in the Late Triassic and led to the exhumation of 7.5-10.5 km of crustal rocks by the end of the Middle Jurassic (ca. 160-150 Ma). The following phase resulted in 1-3 km of basement subsidence and occurred during the Late Jurassic and most of the Early Cretaceous. The basement rocks were then slowly brought to the surface after experiencing 2-3.5 km of exhumation throughout the Late Cretaceous and the Cenozoic. The timing of these episodes of exhumation and subsidence coincides with major tectonic and thermal events in relation with the evolution of the Atlantic and Tethys Oceans, indicating that the effects of their rifting and drifting extended beyond their presumed margins.

  3. Coal belt options



    Whether moving coal long distances overland or short distances in-plant, belt conveyors will always be in demand. The article reports on recent systems developments and applications by Beumer, Horizon Conveyor Equipment, Conveyor Dynamics, Doppelmayr Transport Technology, Enclosed Bulk Systems, ContiTech and Bateman Engineered Technologies. 2 photos.

  4. Trace and rare-earth element geochemistry: A tool for petrogenetic and geotectonic modeling of ensi-matic ortho-amphibolites from Pan-African belt of Obudu Plateau, Southeastern Nigeria

    Ukaegbu V.U.; Beka F.T.


    A model for the petrogenetic affinity and original geotectonic setting of ortho-amphibolites from the Obudu Plateau was tested using the distribution patterns of trace and rare-earth elements from the geochemical analyses of twelve representative amphibolite samples. Discrimination plots, normalized patterns of the incompatible trace elements against average MORB, low ratios of Ba/Nb (9-23) and Ba/Ta (130-327) and other geochemical characteristics suggest that the protoliths were dominantly of tholeiitic MORB composition. The values of the ratios of La/Ta (8.13-10.8), Rb/Sr (0.044).07), Th/U (mainly 4.43-5.43) and Hf/Ta (2.35-2.88) further indicate that the ortho-amphibolites demonstrate E-type MORB characteristics. These features are related to substantial ocean floor divergent tectonic boundary setting rather than marginal basin tectonic setting. This evolutionary pattern appears to be controlled by limited progressive partial melting and fractional crystallization of a single mantle source region, irrespective, however, of variations due to local source heterogeneities. The tholeiitic magmas were most probably generated by hotspot activities on the constructive plate margins and subsequently modified by subduction-related low-K tholeiitic chemistry due to narrowing of a proto oceanic basin between the West African craton and eastern Sahara plate. A likely model, therefore, is that the amphibolites of the Obudu Plateau represent ophiolitic suites with characteristics of enriched mid-ocean floor tholeiites, which were deformed and metamorphosed during a reversed plate motion involving subduction and collision within the Obudu Plateau in the Pan-African orogenic episode.

  5. Benefiting Africans



    Along with thriving Sino-African economic and trade ties,Chinese companies have attached greater importance to their social responsibility to Africans.More than 2,000 sweaters woven by Chinese mothers were sent to orphans and disabled children in Kenya and four other African countries in September.This activity was launched by Hengyuanxiang,a leading Chinese wool manufacturer.

  6. Benefiting Africans


    Along with thriving Sino-African economic and trade ties,Chinese companies have attached greater importance to their social responsibility to Africans.More than 2,000 sweaters woven by Chinese mothers were sent to orphans and disabled children in Kenya and four other African countries in September. This activity was launched by Hengyuanxiang,aleading Chinese wool manufacturer.

  7. Metamorphic belts of Anatolia

    Oberhänsli, Roland; Prouteau, Amaury; Candan, Osman; Bousquet, Romain


    Investigating metamorphic rocks from high-pressure/low-temperature (HP/LT) belts that formed during the closure of several oceanic branches, building up the present Anatolia continental micro-plate gives insight to the palaeogeography of the Neotethys Ocean in Anatolia. Two coherent HP/LT metamorphic belts, the Tavşanlı Zone (distal Gondwana margin) and the Ören-Afyon-Bolkardağ Zone (proximal Gondwana margin), parallel their non-metamorphosed equivalent (the Tauride Carbonate Platform) from the Aegean coast in NW Anatolia to southern Central Anatolia. P-T conditions and timing of metamorphism in the Ören-Afyon-Bolkardağ Zone (>70?-65 Ma; 0.8-1.2 GPa/330-420°C) contrast those published for the overlying Tavşanlı Zone (88-78 Ma; 2.4 GPa/500 °C). These belts trace the southern Neotethys suture connecting the Vardar suture in the Hellenides to the Inner Tauride suture along the southern border of the Kirşehir Complex in Central Anatolia. Eastwards, these belts are capped by the Oligo-Miocene Sivas Basin. Another HP/LT metamorphic belt, in the Alanya and Bitlis regions, outlines the southern flank of the Tauride Carbonate Platform. In the Alanya Nappes, south of the Taurides, eclogites and blueschists yielded metamorphic ages around 82-80 Ma (zircon U-Pb and phengite Ar-Ar data). The Alanya-Bitlis HP belt testifies an additional suture not comparable to the northerly Tavşanlı and Ören-Afyon belts, thus implying an additional oceanic branch of the Neotethys. The most likely eastern lateral continuation of this HP belt is the Bitlis Massif, in SE Turkey. There, eclogites (1.9-2.4 GPa/480-540°C) occur within calc-arenitic meta-sediments and in gneisses of the metamorphic (Barrovian-type) basement. Zircon U-Pb ages revealed 84.4-82.4 Ma for peak metamorphism. Carpholite-bearing HP/LT metasediments representing the stratigraphic cover of the Bitlis Massif underwent 0.8-1.2 GPa/340-400°C at 79-74 Ma (Ar-Ar on white mica). These conditions compares to the Tav

  8. Infrared Kuiper Belt Constraints

    We compute the temperature and IR signal of particles of radius a and albedo α at heliocentric distance R, taking into account the emissivity effect, and give an interpolating formula for the result. We compare with analyses of COBE DIRBE data by others (including recent detection of the cosmic IR background) for various values of heliocentric distance R, particle radius a, and particle albedo α. We then apply these results to a recently developed picture of the Kuiper belt as a two-sector disk with a nearby, low-density sector (40< R<50 endash 90 AU) and a more distant sector with a higher density. We consider the case in which passage through a molecular cloud essentially cleans the solar system of dust. We apply a simple model of dust production by comet collisions and removal by the Poynting-Robertson effect to find limits on total and dust masses in the near and far sectors as a function of time since such a passage. Finally, we compare Kuiper belt IR spectra for various parameter values. Results of this work include: (1) numerical limits on Kuiper belt dust as a function of (R, a, α) on the basis of four alternative sets of constraints, including those following from recent discovery of the cosmic IR background by Hauser et al.; (2) application to the two-sector Kuiper belt model, finding mass limits and spectrum shape for different values of relevant parameters including dependence on time elapsed since last passage through a molecular cloud cleared the outer solar system of dust; and (3) potential use of spectral information to determine time since last passage of the Sun through a giant molecular cloud. copyright copyright 1999. The American Astronomical Society

  9. Belt-up!

    Woof, M.


    Advanced control systems, improved materials and new dust control systems have turned the humble conveyor belt into a sophisticated method for transporting materials. RJB Mining has improved productivity at the Price of Wales colliery in Yorkshire, UK, with the installation of Alstom`s VDM drive system; Qualter Hall`s upgraded conveyor system at the Rugely Power Station in the UK is proving its ability to minimise coal spillage. The article highlights advances by several manufacturers in conveyor technology. 5 photos.

  10. Lap belt injuries in children.

    McGrath, N


    The use of adult seat belts without booster seats in young children may lead to severe abdominal, lumbar or cervical spine and head and neck injuries. We describe four characteristic cases of lap belt injuries presenting to a tertiary children\\'s hospital over the past year in addition to a review of the current literature. These four cases of spinal cord injury, resulting in significant long-term morbidity in the two survivors and death in one child, arose as a result of lap belt injury. These complex injuries are caused by rapid deceleration characteristic of high impact crashes, resulting in sudden flexion of the upper body around the fixed lap belt, and consequent compression of the abdominal viscera between the lap belt and spine. This report highlights the dangers of using lap belts only without shoulder straps. Age-appropriate child restraint in cars will prevent these injuries.

  11. Belt conveyor for recycle aggregate

    Bezrodný, Roman


    This bachelor thesis deals with the belt conveyor for the transport of recycled aggregate in an oblique direction. The aim is to find constructional solutions to the belt conveyor for the assigned transport capacity of 95 000 kg per hour, and the assigned axial distance of 49 m and different height of 12 m. The thesis contains a brief description of the belt conveyor and a description of basic constructional components. It also contains a functional calculation of the capacity and forces acco...

  12. Cenozoic intracontinental deformation of the Kopeh Dagh Belt, Northeastern Iran

    Chu, Yang; Wan, Bo; Chen, Ling; Talebian, Morteza


    arc magmatism. During the Jurassic to Eocene rifting, this belt acted as the southern boundary of the Amu Darya Basin with normal faulting, which is also widespread in the South Caspian Sea and the Black Sea. Moreover, such an extended area became a relatively weak zone within the Eurasian Plate, and could be easily reworked. Because of the collision in the Zagros Belt, the intracontinental compression commenced as early as Late Eocene to Early Oligocene, which is interpreted as tectonic inversion along this weak zone. The western zone of the Kopeh Dagh Belt was also affected by southerly indentation/extrusion of the South Caspian block since middle Miocene, possibly resulting in the different deformation patterns between the western and eastern zones.

  13. SLH Timing Belt Powertrain

    Schneider, Abe


    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  14. Scheelite distribution a long of amphibolitic belt from greenstone belt Barbacena, Minas Gerais, Brazil

    In the middle southern portion of the Minas Gerais state a 60 Km long and 12 Km wide tungsten belt was discovered, and related to the amphibolitic rocks of the Barbacena Greenstone. Tungsten, present as scheelite, is associated with amphibolites, amphibole schists and amphibole gneisses, with chemical characteristics indicating an igneous origin. Chemical analyses on pan concentrates by I.C.P. showed high values on lead, tin, yttrium, lanthanum, cerium and zirconium, and average values for zinc and copper. The scheelite mineralization is probably strata bound and has a possible submarine exhalative origin. (author)

  15. A partial distal humerus from the Middle Pleistocene deposits at Bodo, Middle Awash, Ethiopia

    Carretero, José Miguel; Haile Selassie, Yohannes; Rodríguez García, Laura; Arsuaga, Juan Luis


    The Bodo partial distal humerus with an approximate age of 0.6 million years is one of the very few postcranial remains from the African Middle Pleistocene. Despite its fragmentary status, comparisons of the Bodo humerus with other fossil hominid and modern human samples reveal some insights into African hominids of this time period. The Bodo partial humerus displays distal humeral features very common in the European Middle and Late Pleistocene hominids, such as a relatively w...

  16. Extensive Admixture and Selective Pressure Across the Sahel Belt.

    Triska, Petr; Soares, Pedro; Patin, Etienne; Fernandes, Veronica; Cerny, Viktor; Pereira, Luisa


    Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection). PMID:26614524

  17. The foreland thrust belt in northwestern margin of Yangtze platform and the coalfield structure feature

    Zhang, D.; Jing, Y. [Guangdon Bureau of Coal Geology (China)


    The accumulation and occurrence of coal resources in Yangtze platform and its northwest margin are controlled by the formation and evolution of foreland thrust belt in its northwest margin. The foreland thrust belt can be divided into root zone, middle zone and front zone. There is no coal accumulation root zone, the industrial coal resources are occurred in middle zone, and the coal resources occurred in the front zone are buried deeply. The coalfield structure deformation which is characterized by the imbricate thrusts, duplex thrust, parallel fold, inclined fold, klippen, thrust sheets and fault block, is resulted from the compressive stress of foreland thrust belt. The formation of the thrust belt is the result of long-time evolution of Tethys domain, in which the plates had collided three times along three sutures. 2 refs., 5 figs.

  18. Geography of the asteroid belt

    Zellner, B. H.


    The CSM classification serves as the starting point on the geography of the asteroid belt. Raw data on asteroid types are corrected for observational biases (against dark objects, for instance) to derive the distribution of types throughout the belt. Recent work on family members indicates that dynamical families have a true physical relationship, presumably indicating common origin in the breakup of a parent asteroid.

  19. Saturn's radiation belts in the view of Cassini's MIMI/LEMMS observations

    Roussos, Elias; Krupp, Norbert; Kollmann, Peter; Paranicas, Chris; Armstrong, Tom P.; Mitchell, Donald G.; Krimigis, Stamatios M.; Kotova, Anna


    Energetic charged particle measurements by Cassini's MIMI/LEMMS detector between 2004 and 2013 have revealed that the processes which form and sustain Saturn's radiation belts differ significantly for their electron and ion components. The permanent MeV ion belts are relatively stable in intensity over both short and long time scales, they have a outer boundary that continuously coincides with the L-shell of Saturn's moon Tethys (L=4.89) and comprise different sectors, each separated from the other by an ion depleted region that is centered on an L-shell of one of the planet's inner icy moons. Fluxes within these belts are dominated by secondaries that result from nuclear collisions between Galactic Cosmic Rays and the planet's main rings and atmosphere. Extensions of the ion belts beyond the orbit of Tethys, that may last several months, may occur after the interaction of Saturn's magnetosphere with a Solar Proton Event. Still, these transient extensions have no impact on the structure of the inner belts, making these inner belts ideal for detailed and a precise studies of nuclear source processes, such as CRAND. Contrary to the ion belts, the electron radiation belt is a continuous structure that extends between the outer edge of the main rings and has its outer boundary at an average distance of about 8 Saturn radii from the planet. The latter distance scatters considerably from orbit to orbit, while flux levels within the belt may vary by several orders of magnitude. MIMI/LEMMS observations show a series of interesting features, such as recurrent sudden belt expansions with periods in the order of one to several weeks and considerably variable responses following periods of ICME interactions with Saturn's magnetosphere. As the elecron belts extend until the very dynamic middle magnetosphere and the dominant electron source and loss processes change as a function of L-shell, energy and pitch angle, modelling of these belts is very challenging.

  20. Multi-information-based metallogenic prediction of skarn-type copper polymetallic deposit in the middle segment of Nanjing-Zhenjiang Mesozoic magmatic belt%宁镇中段夕卡岩型铜多金属矿床多元信息成矿预测初步研究

    张术根; 余旭辉; 徐莺


    宁镇中段铜多金属矿床主要为接触交代型矿床.文章以地质环境和成矿规律研究为基础,采用逻辑信息法综合提取地质、遥感、地球物理和地球化学多层次成矿预测信息,构建逻辑信息法成矿预测要素组合.并以此为指导,按照地质成矿条件有利程度、物化探异常强度与规模、环形构造发育程度、遥感解译蚀变显现强度与规模,进行综合判别确定成矿有利位置,圈定区内夕卡岩型矿床重点找矿靶区.%In the middle segment of Nanjing-Zhenjiang Mesozoic magmatic belt, the copper polymetallic deposits are dominated by contact metasomatic type. Based on the geological environment and metallogenic regularity the logical-information method is used to extract multi-metallogenic prediction (geological,remote-sensing, geophysical and geochemical) information of skarn-type cooper polymetallic ores. With this method and comprehensively analyzing the favorable degree of geological metallogenetic conditions,intensity and scale of geophysical-geochemical anomalies, development degree of circular structure, intensity and scale of RS-interpretation alteration, the favorable positions of mineralization are determined, and the key prospecting target area of skarn-type copper deposits in the study area are also delineated. Finally,the potential of the key prospecting target area is discussed in detail.

  1. Ordovician magmatic belt upon pre-Variscan basement in the internal Sardinian Variscides

    Helbing, H.; Frisch, W.; Tiepolo, M.


    A middle Ordovician angular unconformity overlain by conglomerates is exposed in the foreland of the Sardinian Variscides and marks the Sardic phase. Towards the orogen, the foreland is bordered by the nappe zone, in which calc-alkaline suite-derived porphyroids occur in the stratigraphic position of middle Ordovician, but such an unconformity as documented in the foreland is not exposed. The nappe zone records increasing metamorphism from low- to medium-grade towards internal parts and is juxtaposed against the high-grade axial zone along a late Variscan fault. Towards the internal parts, the stratigraphy and the porphyroid occurrence become increasingly uncertain. The Ordovician orthogneisses from Lodè and Tanaunella appear respectively in the medium-grade nappe zone and high-grade axial zone as plutonic equivalents to the porphyroids and rise the question whether these orthogneisses intruded in a sedimentary sequence or in an older basement. In order to solve this classical basement problem, we obtained the following results at the transition between nappe zone and axial zone in NE Sardinia. We discovered porphyroids in the low-grade nappe zone south of the village Lula. Furthermore, the earliest foliation S1 is restricted to the medium-grade nappe zone and high-grade axial zone, but is not developed neither in the orthogneisses nor in the porphyroid-interlayered low-grade nappe zone. In-situ U-Pb isotopic data obtained by laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) on zircon yield 485 +/- 11 Ma for the low-grade Lula porphyroid, 493 +/- 11 Ma for the medium-grade Lodè orthogneiss, and 453 +/- 8 Ma for the high-grade Tanaunella orthogneiss. Besides these Ordovician ages, Neoproterozoic ages are inherited from a Pan-African episode. According to these results we can draw the following conclusions. The internal Sardinian Variscides are made up by an Ordovician magmatic belt upon a pre-Variscan basement. The displacement at the late

  2. Isotopic evidence for two neoproterozoic high-grade metamorphic events in the Brazilia belt

    The Brasilia Belt is part of a Brasiliano/Pan African orogen developed between the Amazon and Sao Francisco cratons. The stabilization of the belt occurred after the last metamorphic event at ca. 620 Ma. There has been increasing geochronological evidence, however, for an older Neoproterozoic metamorphic event at ca. 780 Ma, observed mainly in high grade rocks of three large mafic-ultramafic complexes in the northern part of the belt. In this study we present: (i) new U-Pb and Sm-Nd geochronological data, (ii) a review of the existing metamorphic ages in the Brasilia Belt, and (iii) a discussion on the tectonic model to explain the two Neoproterozoic metamorphic ages (au)

  3. Evaluation of the static belt fit provided by belt-positioning booster seats.

    Reed, Matthew P; Ebert, Sheila M; Sherwood, Christopher P; Klinich, Kathleen D; Manary, Miriam A


    Belt-positioning booster seats are recommended for children who use vehicle seat belts as primary restraints but who are too small to obtain good belt fit. Previous research has shown that belt-positioning boosters reduce injury risk, but the belt fit produced by the wide range of boosters in the US market has not previously been assessed. The present study describes the development of a method for quantifying static belt fit with a Hybrid-III 6-year-old test dummy. The measurement method was applied in a laboratory seat mockup to 31 boosters (10 in both backless and highback modes) across a range of belt geometries obtained from in-vehicle measurements. Belt fit varied widely across boosters. Backless boosters generally produced better lap belt fit than highback boosters, largely because adding the back component moved the dummy forward with respect to the lap belt routing guides. However, highback boosters produced more consistent shoulder belt fit because of the presence of belt routing guides near the shoulder. Some boosters performed well on both lap belt and shoulder belt fit. Lap belt fit in dedicated boosters was generally better than in combination restraints that also can be used with an integrated harness. Results demonstrate that certain booster design features produce better belt fit across a wide range of belt geometries. Lap belt guides that hold the belt down, rather than up, and shoulder belt guides integrated into the booster backrest provided better belt fit. PMID:19393812

  4. Chaos on the conveyor belt

    Sándor, Bulcsú; Tél, Tamás; Néda, Zoltán


    The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by spring to an external static point, and due to the dragging effect of the belt the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can only be achieved by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic dynamics and phase transition-like behavior. Noise induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks, around five.

  5. Age distribution of detrital zircons in the psammitic schist of the Sanbagawa Belt, southwest Japan

    We measured the 206Pb/238U age distribution of detrital zircons in five psammitic schist samples from the Sanbagawa Belt in east-central Shikoku and the western Kii Peninsula to constrain their depositional age. The age-distribution diagrams for the five psammitic schist samples all show that detrital zircons of 100 to 90 Ma are most abundant and the age of the youngest zircon in each sample is less than 80 Ma. Considering the age of the retrogressive metamorphism of these psammitic schists, ca. 80-60 Ma, the protoliths age of the psammitic schists is constrained to 75-70 Ma, correlative to the age of the sandstone of the Middle Shimanto Belt (Yanai, 1984). A similar age-distribution has already been reported for two psammitic schist samples from the Central Unit of the Sanbagawa Belt in the Kanto Mountains (Tsutsumi et al., 2009). Thus the Sanbagawa Belt is most widely occupied by metamorphic rocks originating from rocks of the Middle Shimanto Belt. We also measured the 206Pb/238U age distribution of detrital zircons in Turonian sandstone from the Northern Shimanto Belt in the central Kii Peninsula. The age-distribution diagram shows that detrital zircons of around 128 Ma are most abundant and the age of the youngest zircon in the sample is about 100 Ma. A similar age-distribution has already been reported from a psammitic schist sample from the Southern Unit of the Sanbagawa Belt in the Kanto Mountains, overlying the Central Unit (Tsutsumi et al., 2009). The protolith age is still younger than the metamorphic age of the eclogites in central Shikoku, ca. 120-110 Ma (Okamoto et al., 2004), which occupy the uppermost portion of the Sanbagawa Belt. Although some previous studies suggested that the Sanbagawa Belt consists of metamorphosed Late Jurassic to Early Cretaceous accretionary complex, the present study shows that the belt is largely occupied by metamorphosed Late Cretaceous rocks: the Shimanto Metamorphic Rocks of Aoki et al. (2007). As a result, the

  6. Cancer and African Americans

    ... Population Profiles > Black/African American > Cancer Cancer and African Americans African Americans have the highest mortality rate ... 65MB] At a glance – Top Cancer Sites for African Americans (2008-2012) Cancer Incidence Rates per 100, ...

  7. Utility, Status and Languages in Competition in Middle Belt Nigeria

    ARASANYIN, Olaoba F.


    The diglossic principle implanted into sociolinguistic discourse in the late 1950's afforded a conceptual frame where traditional paradigms and novel parameters for theorizing language within multilingual management coincide and interpenetrate. To Nigeria's multilingual situation, the principles of triglossia have been introduced on two conceptual levels: policy management and public response to policy. However, dimorphous symbiosis between policy guidelines and the attendant applicatory disp...

  8. Tectonics of the Tongbai-Dabie fold belt

    Wenpu, Ma

    The Qinling fold belt is the northernmost branch of the Paleozoic and Mesozoic Tethys in eastern Asia and contains all the inter-reacting records of the North China Block (NCB) and the South China Block (SCB). The Tongbai-Dabie fold belt is its eastern section. The Qinling belt was a collage of two orogens. The north Qinling is a late Paleozoic collision orogen, which started with Proterozoic rifting, transforming into active continental margin during the middle Ordovician. The intermitten ophiolite fragments indicate the existence of an oceanic crust at that time. The collision that occurred in the Devonian was an east-west diachronous process. The main suture zone is marked by ophiolitic melange extending nearly 500 km. The late Mesozoic molasse, volcano-plutonic activity and huge imbricate thrust system all respond to the further shortening of the crust and adjustment of the intracontinental strain. The south Qinling east of the Nanyang Basin is located to the south of Tongbai mountain. A pile of thick Sinian-Silurian volcanic and marine clastic deposits imply another marine incursion. Its history in south Shaanxi could continue to the Mesozoic. The flysch trough represented by Xinyang group may be the key area for revealing the relationship between north and south Qinling. The discussion in the paper is mainly focused on the nature and evolution of the Tongbai-Dabie fold belt.

  9. East African Running: Toward a Cross-Disciplinary Perspective

    Yannis Pitsiladis; John Bale; Craig Sharp; Timothy Noakes


    DESCRIPTION "East African Running: Toward a Cross-disciplinary Perspective" examines the secret of those runners in being the top athletes of middle and long distance running. PURPOSE This book aims to discuss the anatomical, physiological, biomechanical, genomic, psychological and sociological conditions which lead East African runners to success. AUDIENCE This all-inclusive book about favoured East African runners is a remarkable source for all sports and social sciences professionals as we...

  10. 长江中下游成矿带抛刀岭大型斑岩型金矿特征及找矿前景%Characteristics and Prospects of Paodaoling Large Porphyry Gold Deposit in the Middle-lower Yangtze River Metallogenic Belt

    段留安; 杨晓勇; 汪方跃


    抛刀岭金矿位于长江中下游成矿带安庆-池州矿集区,累计金金属量大于22 t ,为池州地区首例大型金矿床。该矿床金矿体主要产在英安玢岩中,基本不伴生其他有益金属元素,为独立金矿床。通过详细的矿床地质特征描述,结合已有斑岩型金矿的成矿模式,同时利用以往对该含矿岩体U-Pb锆石定年及相关地球化学研究,综合分析认为该矿为产在早白垩纪岛弧背景下的贫铜斑岩型金矿床,同时局部矿段在成矿过程中还经历了热液叠加作用。矿体产出严格受 NE向构造岩浆岩带控制,含矿岩体出露面积小于1.0 km2,属于典型的小岩体成大矿。运用“相似类比”、“矿床谱系”、“趋势外推”、“综合信息评价”等原则,指出该矿具有特大型金矿的潜质;同时,受同一 NE向构造控制的乌石、白虎山及自来山等同期岩浆岩发育地区,具有与抛刀岭金矿类似的成矿条件,是未来工作的重点靶区;发育于上述同期岩浆岩之间的志留纪地层中的破碎带蚀变岩、与斑岩型矿床配套产出的低温热液多金属硫化物型矿床等,都将是外围工作的重点研究地区。%Paodaoling gold deposit is located in Anqing-Chizhou ore concentrated area of the middle-lower Yangtze River metallogenic belt.It is the first large gold deposit discovered in Chizhou area with more than 22 t gold.Paodaoling gold deposit is independent with little other economic metal elements,and develop mainly in dacite-porphyrite.According to the detailed description of geological characteristics of gold deposit,combined with the metallogenic model of porphyry gold deposit and the characteristics of zircon U-Pb dating and geochemistry,it is proposed that Paodaoling gold deposit is a Cu-poor porphyry gold deposit formed in Early Cretaceous arc environment,and part of ore blocks experiences hydrothermal alteration.Ore bodies,which are

  11. Some problems of geologic relations between the Amazon craton and east margins fold belts

    This paper deals with some geologic problems related to the limits between the Amazon craton and the fold belts developed at its margins during the Precambrian. These limits are diversified but clearly recognized. To the north, the Araguaia-Tocantins fold belt, of presumed Middle Proterozoic age, is separated from the cratonic block by a deep marginal fracture zone permeated by mafic and ultramafic rocks. The geologic, magmatic and aeromagnetic characteristics of this zone point out the presence of deep faults, supposed to be of Middle Proterozoic age. The southern Paraguay fold belt constitutes and accurated zone of linear structures supposed to be of Late Proterozoic development. Despite the great increase of knowledge during the last ten years many tectonic, stratigraphic and geochronologic problems remain unsolved. The aim of this paper is to point out some of these problems and suggest specific studies to solve them. (author)

  12. Launching jets from accretion belts

    Schreier, Ron


    We propose that sub-Keplerian accretion belts around stars might launch jets. The sub-Keplerian inflow does not form a rotationally supported accretion disk, but it rather reaches the accreting object from a wide solid angle. The basic ingredients of the flow are a turbulent region where the accretion belt interacts with the accreting object via a shear layer, and two avoidance regions on the poles where the accretion rate is very low. A dynamo that is developed in the shear layer amplifies magnetic fields to high values. It is likely that the amplified magnetic fields form polar outflows from the avoidance regions. Our speculative belt-launched jets model has implications to a rich variety of astrophysical objects, from the removal of common envelopes to the explosion of core collapse supernovae by jittering jets.

  13. Kuiper Belts Around Nearby Stars

    Nilsson, R; Brandeker, A; Olofsson, G; Pilbratt, G L; Risacher, C; Rodmann, J; Augereau, J -C; Bergman, P; Eiroa, C; Fridlund, M; Thébault, P; White, G J


    In order to detect and characterise cold extended circumstellar dust originating from collisions of planetesimal bodies in disks, belts, or rings at Kuiper-Belt distances (30--50\\,AU or beyond) sensitive submillimetre observations are essential. Measurements of the flux densities at these wavelengths will extend existing IR photometry and permit more detailed modelling of the Rayleigh-Jeans tail of the disks spectral energy distribution (SED), effectively constraining dust properties and disk extensions. By observing stars spanning from a few up to several hundred Myr, the evolution of debris disks during crucial phases of planet formation can be studied. // We have performed 870\\,$\\mu$m observations of 22 exo-Kuiper-Belt candidates, as part of a Large Programme with the LABOCA bolometer at the APEX telescope. Dust masses (or upper limits) were calculated from integrated 870\\,$\\mu$m fluxes, and fits to the SED of detected sources revealed the fractional dust luminosities $f_{\\mathrm{dust}}$, dust temperatures...

  14. Partnerships in the Middle East: Interventionist Endeavors?

    Aarøe Jørgensen, Jakob


    This chapter aims to analyse NATO’s two Middle Eastern and North African (MENA)1 partnership programmes – the Mediterranean Dialogue (MD) and the Istanbul Cooperation Initiative (ICI). The chapter aims to answer the questions: (1) why does NATO engage with MENA partners; (2) what are the obstacles...... that MD and ICI face, and; (3) is the new flexible partnership policy a step towards more constructive Middle Eastern partnerships?...

  15. African dance

    Mumberson, Stephen


    The RE Open will be shown at the Mall Gallery London and the international section was judged by major practitioners and educators, print dealers and collectors, President of RE and Keeper of the Ashmolean Museum Dr Bren Unwin, John Purcell, Deborah Roslund, Colin Harrison, Dave Ferry, and Mark Hampson. Piece selected "African Dance" print.

  16. Ideal Body Size as a Mediator for the Gender-Specific Association between Socioeconomic Status and Body Mass Index: Evidence from an Upper-Middle-Income Country in the African Region

    Yepes, Maryam; Maurer, Jürgen; Stringhini, Silvia; Viswanathan, Barathi; Gedeon, Jude; Bovet, Pascal


    Background: While obesity continues to rise globally, the associations between body size, gender, and socioeconomic status (SES) seem to vary in different populations, and little is known on the contribution of perceived ideal body size in the social disparity of obesity in African countries. Purpose: We examined the gender and socioeconomic…

  17. Study of thermal conditions at belt slippage

    Hoffmann, R.; Pampel, W.; Pfleger, P.


    Conveyor belt slippage experiments are carried out on the Chrudim (Czechoslovakia) industrial sized test stand for belt widths up to 1 m and driving drum forces up to 400 kW. The stand is operated jointly by TAKRAF (GDR) and VITKOVICE VUTZ, Prague. From 1972 to 1981, 7 belt conveyor fires occurred in GDR brown coal surface mines due to belt slippage. One of these cases led to a belt fire after only 15 s at 100% belt slippage. Aim of the study was to determine accurate permissible slippage values. Design of the test stand is explained as well as test procedures with belt slippage at the driving drum varying between 10 and 100%. Belt driving parameters were measured along with temperature of the drum surface. The heat penetration parameter b (in kJ/m/sup 2/) was calculated. Maximum temperatures up to 150 C were measured on the drum during partial slippage and 370 C at 100% belt slippage. The ignition temperature of rubber abrasion fines was also analyzed and found to vary between 40 and 318 C, i.e. substantially lower than belt and drum layer ignition temperatures. Graphs and diagram of slippage measurement results are calculated. Values for permissible maximum slippage time for operating belt slippage monitoring devices are shown. These devices are required to be installed in the GDR at heavy mine belt conveyors with driving forces exceeding 500 kW. 8 refs.

  18. French experience in seat belt use.

    Lassarre, S. & Page, Y.


    This paper concerns the French experience in seat belt use. As well as the seat belt regulations, the strategies employed to reinforce the wearing of seat belts by using information and encouragement campaigns and checks by the police and gendarmerie are described here along with their timetables an

  19. 长江中下游成矿带贵池抛刀岭金矿含矿岩体年代学及地球化学研究%Geochemistry and zircon U-Pb age of ore-bearing porphyry in the Paodaoling gold deposit in Guichi, Middle-Lower Yangtze metallogenic belt

    段留安; 杨晓勇; 汪方跃; 邓江洪; 孙卫东


    贵池抛刀岭金矿位于长江中下游成矿带安庆-贵池矿集区,是该地区首次发现的独立玢岩型金矿床,含矿岩体主要为蚀变矿化的英安玢岩.经过近两年的地质勘查,该矿床已接近大型金矿床规模.通过对抛刀岭金矿含矿岩体锆石LA-ICPMS U-Pb测定,其成岩年龄为146.8±2.4Ma和141.3±1.0Ma(2σ),与长江中下游地区中生代大规模铜金成矿事件时间一致.全岩地球化学研究表明,该岩石为过铝质,富集大离子亲石元素(K、Rb、Pb),亏损高场强元素(Nb、Ta、Ti)和轻稀土富集等地球化学特征.较高的锆石Ce4+/Ce3+和EuN/EuN*显示抛刀岭含矿岩体具有较高的氧逸度特征.构造判别图解显示这套含矿岩石属火山弧花岗岩(VAG),与长江中下游铜金矿床含矿岩体形成于同一构造背景下,即太平洋俯冲作用引起的洋壳和地幔楔熔融形成.%The Paodaoling gold deposit is the first discovered porphyry type gold deposit in Anqing-Guichi ore-cluster region in the Middle-Lower Yangtze metallogenic belt ( LYRB). The host rocks of the Paodaoling gold deposit are trachyte andesitic porphyries. Zircon LA-ICP-MS U-Pb dating of two ore-bearing porphyries are 146. 8 ±2. 4Ma and 141. 3 ± 1. OMa (2σ) , according with the main mineralization time of LYRB. Whole rock geochemistry indicates that the ore-bearing porphyries are peraluminous, enriched in K-Rb-Pb and light REE, depleted in Nb-Ta-Ti, similar to crustal origination. These porphyries show volcanic arc granite affinities. The higher ratios of Ce4+ VCe3+ and Eun/Eun, calculated from zircon data indicate that the Paodaling intrusion has higher oxygen fugacity with potentiality for Au formation. We conjecture that the Paodaoling gold deposit was probably related to melting of mantle wedge during subduction between Paleo-Pacific plate and Izanagi plate.

  20. Geological setting and tectonic subdivision of the Neoproterozoic orogenic belt of Tuludimtu, western Ethiopia

    Allen, Alistair; Tadesse, Gebremedhin


    The N-S trending Tuludimtu Belt in the extreme west of Ethiopia has been subdivided into five lithotectonic domains, from east to west, the Didesa, Kemashi, Dengi, Sirkole and Daka domains. The Kemashi, Dengi and Sirkole Domains, forming the core of the belt, contain volcano-sedimentary successions, whilst the Didesa and Daka Domains are gneiss terranes, interpreted to represent the eastern and western forelands of the Tuludimtu Belt. The Kemashi Domain, which consists of an ophiolitic sequence of ultramafic and mafic volcanic and plutonic rocks together with sedimentary rocks of oceanic affinity, is interpreted as oceanic crust and is considered to represent an arc-continent suture zone. The Dengi Domain, composed of mafic to felsic volcanic and plutonic rocks, and a sequence of volcanoclastic, volcanogenic, and carbonate sediments, is interpreted as a volcanic arc. The Sirkole Domain consists of alternating gneiss and volcano-sedimentary sequences, interpreted as an imbricated basement-cover thrust-nappe complex. All the domains are intruded by syn- and post-kinematic Neoproterozoic granitoids. Structural analysis within the Didesa and Daka Domains indicate the presence of pre-Pan African structures, upon which Neoproterozoic deformation has been superimposed. The gneissic rocks of these two domains are regarded as pre-Pan African continental fragments amalgamated to West Gondwana during Neoproterozoic collision events. Unconformably overlying all of the above are a series of tilted but internally undeformed conglomerate-sandstone-shale sequences, regarded as post-accretionary molasse-type deposits, formed during gravitational collapse of the Tuludimtu Belt. The Tuludimtu Belt is interpreted as a collision orogenic belt formed during the assembly of West Gondwana prior to final closure of the Mozambique Ocean.

  1. New investigations in southwestern Guinea: consequences for the Rokelide belt (West Africa)

    Villeneuve, Michel; Bellon, Hervé; Corsini, Michel; Le Metour, Joël; Chatelee, Sébastien


    The southern Guinean terranes belong to the "Rokelide belt" that is located in the southwestern part of the West African craton (Senegal to Liberia). Field investigations and K-Ar and 40Ar-39Ar radiometric analysis performed on samples collected from southern Guinea provide a new interpretation for metamorphic terranes not yet dated. A K-Ar whole-rock age of a gneiss and 40Ar-39Ar plateau ages of amphiboles separated from a mylonitic gneiss of the Ouankifondi formation and a gneiss from the Kissi-Kissi formation yield several Pan-African metamorphic ages at circa 650, 560, and 530 Ma, respectively. Field investigations show that these formations are unconformably capped by the Kolente group. The previous structural framework and the geodynamic evolution of the Rokelide belt based on the coeval evolution of the Ouankifondi and Kissi-Kissi formations and the Kolente group are reassessed. The Rokelide belt is linked to the Bassaride belt. Correlations with adjacent Sierra Leonean terranes and with northern Guinea and Senegal are considered.

  2. Uplift of the South African Plateau: mantle-scale deformation, long wavelength relief growth and offshore sediment budget

    Guillocheau, François; Dauteuil, Olivier; Baby, Guillaume; Robin, Cécile


    The South African Plateau is one of the largest very long wavelength relief (x1000 km) of the world that could be related to mantle dynamics and the effect of the African superplume. Unfortunately, the timing of the uplift and the different steps of the relief growth are still debated with a Late Cretaceous uplift scenario and an Oligocene one. Whatever model, few attentions were paid to the evolution of the overall geomorphic system, from the upstream erosional system to the downstream depositional system. This study is based, onshore, on the mapping and chronology of all the macroforms (weathering surfaces and associated alterites, pediments and pediplains, incised rivers, wave-cut platforms) dated by intersection with the few preserved sediments and the volcanics (mainly kimberlites pipes) and, offshore, on a more classical dataset of seismic lines and petroleum wells (characterization and dating of forced regression, sediment volume measurement, etc..). The main result of this study is that the South African Plateau is an old Late Cretaceous Plateau reactivated during Paleogene times and fossilized since the Middle Miocene. • During Late Cretaceous, in a semiarid climatic setting, the main uplift occurred from the east (around 95 Ma) to the west (around 75 Ma) and could result from the migration of the African plate over the African superplume: This is the paroxysm of the erosion with the growth of a large delta offshore present-day Orange River mouth (sedimentation rate around 100 000 km3/Ma). • During Paleocene - Mid Eocene times, in more humid conditions and in response to a more subtle long wavelength deformation, pedimentation occurred mainly localised along Cape Fold Belt feeding a large delta offshore western Cape Peninsula. During Mid Eocene times, all those landscapes are fossilized and weathered by laterites. • Late Eocene and Oligocene is the second period of uplift of the Plateau, localised along its Indian Ocean side (Drackensberg Moutains

  3. Obesity and African Americans

    ... Data > Minority Population Profiles > Black/African American > Obesity Obesity and African Americans African American women have the ... ss6304.pdf [PDF | 3.38MB] HEALTH IMPACT OF OBESITY More than 80 percent of people with type ...

  4. The quality turn in South Africa: insights from a comprehensive investigation into the food quality behaviours, perceptions and knowledge of South African consumers with a focus on middle and upper socioeconomic groups

    Vermeulen, Hester; Bienabe, Estelle


    Internationally, alternative food quality movements have given rise to a quality turn from the mass consumption model toward an increasing qualitative differentiation of products and demand (Allaire, 2002). While food quality trends and their implications have been widely analyzed internationally, little has been written on the local quality dynamics in South Africa, a country with clear dualistic socio-economic features. This paper aims to contribute to the understanding of South African con...

  5. African Stock Market Performance Dynamics: A Multidimensional Convergence Assessment

    Simplice A, Asongu


    This paper dissects with great acuteness, the issues of convergence in financial performance dynamics in the African continent through the lenses of stock market capitalization, value traded, turnover and number of listed companies. The empirical evidence is premised on 11 homogenous panels based on regions (sub-Saharan and North Africa), income-levels (Low, Middle, Lower-middle and Upper-middle), legal-origins (English common-law and French civil-law) and religious dominations (Christianity ...

  6. Middle East

    This document summarizes in a series of tables and graphs the energy profile of Middle East: production, imports, exports, stock change and consumption of crude oil and LNG, oil products, natural gas, coal and lignite, electricity, global primary consumption and energy balance. (J.S.)

  7. Synchronous and Cogged Fan Belt Performance Assessment

    Cutler, D.; Dean, J.; Acosta, J.


    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  8. Belt technology stretches conveyors' coverage



    With China the leading growth engine in the conveyor market, leading belt manufacturers are establishing local manufacturing plants to boost their presence. Fenner is planning to almost triple production capacity over the next three years, with a third of its investment in China. Shanxi-Phoenix Conveyor Belt Systems is a joint venture between Phoenix Conveyor Belt Systems GmbH, now part of ContiTech Ag, and its Chinese partners Lu An Mining Group Co. Ltd. and Jingcheng Anthracite Group Co. Ltd. It manufacturers steel cable belts, PVC and multi-ply belts for coal mines and power plants. Recent belt designs by FennerEurope and Metso Minerals are reported. 2 photos.

  9. Characteristics and its uranium metallogenic potential of the granite belt between Bange and Jiali county, tibet

    The granite belt between Bange and Jiali county is a composite batholith which intruded at multistage, it con- trolled by several groups of the fault system, the alteration is developed, with the alaskite, aplite, pegmatitic vein intruded, it is type Ⅰ in the beginning of forming, and change to type S in the late time. There is a large of geochemical anomalies of uranium (U>6.8 X 10-6) in Gulu town and Sangba village, of which middle of the granite belt and Bianba county of which east of the granite belt, that anomalies area have 1200 km2, 800 km”2 and 1500 km2. All the anomalies is considered that its forming relate to batholith and its external contact, so it shows that it has favorite geological conditions for granite type uranium metallogenesis. (authors)


    Li Yinghui; Gao Qing; Jian Kailin; Yin Xuegang


    The nonlinear dynamic responses of viscoelastic axially transmission belts are investigated and the Kelvin viscoelastic differential constitutive model is employed to characterize the material property of belts. The generalized equation of motion is obtained for a viscoelatic axially transmission belts with geometric nonlinearity first, and then is reduced to be a set of second-order nonlinear ordinary differential equations by applying Galerkin's method. Finally, the effects of viscosity parameter and elastic parameter and the moving velocity of the belts on the transient responses are investigated by the research of digital simulation.

  11. Cabacal belt, southern Amazon craton in Mato Grosso-Brazil: Implications for the tectonic evolution (more complications)

    The Amazon Craton covers an area of about 250000Km2 on the northern part of the South America. The Precambrim time history of the craton has been divided in geochronological provinces (Cordani et al. 1979; Teixeira et al. 1989; Tassinari et al. 1996; Tassinari and Macambira, 1999; and Santos et al. 2000). The Cabacal Belt covers an area of approximately 350 square kilometers in the southern region of the Amazon Craton, Mato Grosso-Brazil. It is a narrow NNW trending belt of greenchist to amphibolite grade volcano-sedimentary rocks intruded by plutonic rocks of tonalitic to granitic composition and mafic sills/dikes (Pinho et al., 1997). To the East it is bounded by Mesoproterozoic sediments of the Aguapei Group. To the West it is separated from the Araputanga Belt by a metamorphic complex, chiefly made of orthogneisses. The Cabacal Belt is one of the three NNW trending belts from the Alto Jauru Greenstone Belt. As a whole, the supracrustal rocks of the Cabacal Belt consist of three units: a basal unit comprising mafic lavas and breccias; a middle unit of felsic to intermediate metavolcanics rocks with interlayered tuffs and sediments; and a top unit of dacite-rhyodacit lavas, tuffs, and sediments (clastic and chemical). Monteiro et al. (1986) named these units as Mata Preta (MPF), Manuel Leme (MLF) and Rancho Grande (RGF) formations respectively. Leite et al. (1986) used the name Quatro Meninas Complex for the basic unit We analyzed zircons from seven samples in the Cabacal Belt, including samples from the volcano-sedimentary sequence, from intrusive bodies, and from the gneiss that separates the Cabacal Belt from the Araputanga Belt (au)

  12. Brusque belt: a monocyclic evolution ?

    This paper discusses the radiometric data for the Brusque Belt (SC) where Rb-Sr isochrons, U-Pb in zircons, K-Ar in minerals and whole rock Sm-Nd model ages are available. The analysis of these results reveals two main groups, without intermediate values. The first, 500 to 800Ma., is related to magmatic and metamorphic ages and the second, 1600-2000Ma begin with the (probably) sedimentation age. A monociclic evolution is proposed, but with uncertanties in the age of the first metamorphic phase. (author)

  13. Evolution, source and tectonic significance of Early Mesozoic granitoid magmatism in the Central Asian Orogenic Belt (central segment)

    Li, Shan; Wang, Tao; Wilde, Simon A.; Tong, Ying


    Numerous Early Mesozoic granitoids have been recognized from the central segment of the Central Asian Orogenic Belt (CAOB). They can be broadly classified into two groups according to zircon U-Pb ages: an early-stage group covering the time span from Early to Middle Triassic (250-230 Ma) and a late-stage group emplaced during Late Triassic to Early Jurassic (ca. 230-190 Ma). Early-stage (250-230 Ma) granitoids are mainly distributed in the western Central Mongolia-Erguna Belt (CMEB), the western Altai Belt (AB), the South Mongolia-Xing'an Belt (SMXB) and the Beishan-Inner Mongolia-Jilin Belt (BIJB). They consist mainly of quartz-diorites, granodiorites and monzogranites, mostly of I-type, with minor mafic intrusions, with some of them showing adakite-like signatures and some with S-type features. Late-stage (230-190 Ma) granitoids mainly occur in the North Mongolia-Transbaikalia Belt (NMTB), the eastern CMEB (Erguna massif) and the eastern Altai Belt (AB). They are predominately syenogranites, monzogranites and syenites, associated with many alkaline granites and mafic intrusions and are A-type and transitional I-A type or highly fractionated I-type granites.

  14. Apparatus for heat treating plastic belts

    Topits, A., Jr.


    Apparatus performs programed rotating, stretching/shrinking and heat treatment necessary to fabrication of high-performance plastic belts. Belts can be treated in lengths varying from 7 to 48 in., in widths up to 1 in., and in thicknesses up to approximately 0.003 in.

  15. Parameters affecting seat belt use in Greece.

    Yannis, G; Laiou, A; Vardaki, S; Papadimitriou, E; Dragomanovits, A; Kanellaidis, G


    The objective of this research is the exploration of seat belt use in Greece and particularly the identification of the parameters affecting seat belt use in Greece. A national field survey was conducted for the analytical recording of seat belt use. A binary logistic regression model was developed, and the impact of each parameter on seat belt use in Greece was quantified. Parameters included in the model concern characteristics of car occupants (gender, age and position in the car), the type of the car and the type of the road network. The data collection revealed that in Greece, the non-use of seat belt on the urban road network was higher than on the national and rural road network and young and older men use seat belts the least. The developed model showed that travelling on a national road is negative for not wearing the seat belt. Finally, the variable with the highest impact on not wearing a seat belt is being a passenger on the back seats. PMID:21452095

  16. Understanding Quaternions and the Dirac Belt Trick

    Staley, Mark


    The Dirac belt trick is often employed in physics classrooms to show that a 2n rotation is not topologically equivalent to the absence of rotation whereas a 4n rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors…

  17. Situational characteristics of safety belt use.

    Fockler, S K; Cooper, P J


    Past research concerning the use and nonuse of safety belts has tended to stereotype users and nonusers as distinct entities on the basis of a single observed situation. The thought processes underlying the reasons given by drivers for using or not using seat belts have not been explored. The purpose of this study was to observe belt use by a group of drivers and describe factors contributing to their use or nonuse as defined by the drivers themselves. In-depth interviews were undertaken with 239 drivers whose safety belt wearing behavior was observed in specific city or highway driving locations. Vehicle license numbers, gender, and age group of selected drivers were used to retrieve driver records and insurance policy data. Open-ended questions were asked concerning their reasons for use or nonuse and their attitudes towards safety belts and other types of traffic safety countermeasures. Driver attitudes, characteristics, and records were compared between observed safety belt user and nonuser groups to validate variables predicting use or nonuse. Respondents' descriptions of the social and personal context of their choice to use or not use safety belts provide a broader view of seat belt wearing that suggests implications for planning future enforcement and education programs. PMID:2331287

  18. Petrophysical and sedimentological characterization of the Zuata field in Orinoco Oil Belt. Venezuela

    The Zuata field is in the middle of the Jun in block in Orinoco Oil Belt and its production is handled by the district of Cabrutica which planning to develop a comprehensive reservoir model that allows leverage a correct management of hydrocarbon reserves. The purpose of this study is to generate a sedimentological and petrophysical model to know the architecture and quality of the rocks

  19. Heart Disease and African Americans

    ... Minority Population Profiles > Black/African American > Heart Disease Heart Disease and African Americans Although African American adults are ... were 30 percent more likely to die from heart disease than non-Hispanic whites. African American women are ...

  20. Infant Mortality and African Americans

    ... African American > Infant Heath & Mortality Infant Mortality and African Americans African Americans have 2.2 times the infant mortality rate ... birthweight as compared to non-Hispanic white infants. African Americans had almost twice the sudden infant death syndrome ...

  1. Alice Walker: "The Diary of an African Nun" and Dubois Double Consciousness

    Fontenot, Chester J.


    Analyzes Alice Walker's novel and notes that the plight of the African nun is that of the black intellectual or middle-class who find themselves caught between two worlds which are at once complementary and contradictory. (Author)

  2. The Gould's Belt distance survey

    Loinard, L; Torres, R M; Dzib, S; Rodriguez, L F; Boden, A F


    Very Long Baseline Interferometry (VLBI) observations can provide the position of compact radio sources with an accuracy of order 50 micro-arcseconds. This is sufficient to measure the trigonometric parallax and proper motions of any object within 500 pc of the Sun to better than a few percent. Because they are magnetically active, young stars are often associated with compact radio emission detectable using VLBI techniques. Here we will show how VLBI observations have already constrained the distance to the most often studied nearby regions of star-formation (Taurus, Ophiuchus, Orion, etc.) and have started to provide information on their internal structure and kinematics. We will then briefly describe a large project (called The Gould's Belt Distance Survey) designed to provide a detailed view of star-formation in the Solar neighborhood using VLBI observations.

  3. Strategy for replacing conveyor belts in complex haulage systems

    Gladysiewicz, L.; Jurdziak, L.; Masella, J.


    Discusses service life and reliability of conveyor belts used for mine haulage in brown coal surface mining and a method for optimizing belt service life. Based on analysis of operation of 900-1,200 m long belt conveyors in the Konin surface mine, failure rates and factors that influence belt reliability were determined. Effects of joints, length of belt sections and service life of each belt section were analyzed. Formulae for determining the optimum time interval for replacing belt sections on a long belt conveyor were derived. The formulae consider cost of new belt sections, replacement cost and haulage losses associated with possible belt failure caused by excessive belt service life. The optimization procedure has been successfully tested at the Turow surface mine and power plant. 4 refs.

  4. African Americans and Glaucoma

    ... Involved News About Us Donate In This Section African Americans and Glaucoma email Send this article to ... glaucoma is the leading cause of blindness in African Americans. Half of those with glaucoma don't ...

  5. Physical Activities and Sedentary Pursuits in African American and Caucasian Girls

    Dowda, Marsha; Pate, Russell R.; Felton, Gwen M.; Saunders, Ruth; Ward, Dianne S.; Dishman, Rod K.; Trost, Stewart G.


    The purposes of this study were to describe and compare the specific physical activity choices and sedentary pursuits of African American and Caucasian American girls. Participants were 1,124 African American and 1,068 Caucasian American eighth-grade students from 31 middle schools. The 3-Day Physical Activity Recall (3DPAR) was used to measure…

  6. School Adjustment and the Academic Success of Rural African American Early Adolescents in the Deep South

    Farmer, Thomas W.; Irvin, Matthew J.; Thompson, Jana H.; Hutchins, Bryan C.; Leung, Man-Chi


    This study examined the relationship between end-of-year grades and the academic, behavioral, and social characteristics of rural African American youth. Participants included 392 7th and 8th grade students from 2 rural middle schools in the south. Participants were African American and were from 2 communities that have child poverty rates…

  7. Diabetes in African Americans

    Marshall, M.


    African Americans have a high risk for type 2 diabetes. Genetic traits, the prevalence of obesity, and insulin resistance all contribute to the risk of diabetes in the African American community. African Americans have a high rate of diabetic complications, because of poor glycaemic control and racial disparities in health care in the USA. African Americans with diabetes may have an atypical presentation that simulates type 1 diabetes, but then their subsequent clinical course is typical of t...

  8. Seat belt use law in developing countries



    Objective:To highlight the way to successful implementation of mandantory seat belt use law in developing countries particulary where have significant increase in number or cars and subsequent increase in car occupant casualties.Methods:Literatures concerning seat belt use were reviewed and experiences of the world.Satisfactory or not,investigated.It summed up general aspects of seat belt use as well as benefits,attitude toward legislation and measures to enhance the usage.Results:Seat belt use has been proven and stood time tested as the most effective means to protect car occupants from road crash injuries.It appears to be arduous to achieve the golal of seat belt use law in developing countries. but possible via strategies appropriately leading to legislation and promotion of the belt usage.Conclusions:It is prime necessity for the government authorities to recognize the importance of seat belt use.There needs an organizational structure composed of relevant professional from both private and government sectors which is able to carry out every steps toward successful legislation and implementation:education,publicity,enforcement,evaluation and dissemination of the law's benefits.


    李映辉; 高庆; 蹇开林; 殷学纲


    Based on the Kelvin viscoelastic differential constitutive law and the motion equation of the axially moving belt, the nonlinear dynamic model of the viscoelastic axial moving belt was established. And then it was reduced to be a linear differential system which the analytical solutions with a constant transport velocity and with a harmonically varying transport velocity were obtained by applying Lie group transformations. According to the nonlinear dynamic model, the effects of material parameters and the steady-state velocity and the perturbed axial velocity of the belt on the dynamic responses of the belts were investigated by the research of digital simulation. The result shows: 1 ) The nonlinear vibration frequency of the belt will become small when the relocity of the belt increases. 2 ) Increasing the value of viscosity or decreasing the value of elasticity leads to a deceasing in vibration frequencies. 3 ) The most effects of the transverse amplitudes come from the frequency of the perturbed velocity when the belt moves with harmonic velocity.

  10. African American Suicide

    African American Suicide Fact Sheet Based on 2012 Data (2014) Overview • In 2012, 2,357 African Americans completed suicide in the U.S. Of these, ... 46 per 100,000. • The suicide rate for African Americans ages 10-19 was 2.98 per ...

  11. From transmission error measurement to Pulley-Belt slip determination in serpentine belt drives: influence of tensioner and belt characteristics

    Manin, Lionel; Michon, Guilhem; Rémond, Didier; Dufour, Regis


    Serpentine belt drives are often used in front end accessory drive of automotive engine. The accessories resistant torques are getting higher within new technological innovations as stater-alternator, and belt transmissions are always asked for higher capacity. Two kind of tensioners are used to maintain minimum tension that insure power transmission and minimize slip: dry friction or hydraulic tensioners. An experimental device and a specific transmission error measurement method have been u...

  12. Simulation of engine auxiliary drive V-belt slip motion. Part 1. Development of belt slip model; Engine hoki V belt slip kyodo no simulation. 1. Belt slip model no kaihatsu

    Kurisu, T. [Mazda Motor Corp., Hiroshima (Japan)


    V-belts are widely used for driving auxiliary components of an engine. Inadequet design of such belt system sometimes results in troubles such as belt squeak, side rubber separation and/or bottom rubber crack. However, there has been no design tools which can predict belt slip quantitatively. The author developed a motion simulation program of Auxiliary Drive V-Belt System considering belt slip. The program showed good prediction accuracy for belt slip motion. This paper describes the simulation model. 1 ref., 12 figs.

  13. The Compositional Structure of the Asteroid Belt

    DeMeo, Francesca E; Walsh, Kevin J; Chapman, Clark R; Binzel, Richard P


    The past decade has brought major improvements in large-scale asteroid discovery and characterization with over half a million known asteroids and over 100,000 with some measurement of physical characterization. This explosion of data has allowed us to create a new global picture of the Main Asteroid Belt. Put in context with meteorite measurements and dynamical models, a new and more complete picture of Solar System evolution has emerged. The question has changed from "What was the original compositional gradient of the Asteroid Belt?" to "What was the original compositional gradient of small bodies across the entire Solar System?" No longer is the leading theory that two belts of planetesimals are primordial, but instead those belts were formed and sculpted through evolutionary processes after Solar System formation. This article reviews the advancements on the fronts of asteroid compositional characterization, meteorite measurements, and dynamical theories in the context of the heliocentric distribution of...

  14. Handbook Timing Belts Principles, Calculations, Applications

    Perneder, Raimund


    Timing belts offer a broad range of innovative drivetrain solutions; they allow low-backlash operation in robot systems, they are widely used in automated processes and industrial handling involving highly dynamic start-up loads, they are low-maintenance solutions for continuous operation applications, and they can guarantee exact positioning at high operating speeds. Based on his years of professional experience, the author has developed concise guidelines for the dimensioning of timing belt drives and presents proven examples from the fields of power transmission, transport and linear transfer technology. He offers definitive support for dealing with and compensating for adverse operating conditions and belt damage, as well as advice on drive optimization and guidelines for the design of drivetrain details and supporting systems. All market-standard timing belts are listed as brand neutral. Readers will discover an extensive bibliography with information on the various manufacturers and their websites. This...

  15. Dynamics of the outer asteroid belt

    This paper considers the issue of modeling the dynamics of the outer asteroid belt. The hypotheses and assumptions of an asteroid-belt model are discussed together with their problems, of which gaps at some mean-motion resonances with Jupiter and the depletion of the outer belt are the most outstanding ones. Particular attention is given to the theory of the 2:1 gap, the depletion problem, and the mechanisms of dynamical protection against strong perturbations by Jupiter. It is suggested that the observed asteroids must have gone through a process of natural selection as a result of which all objects in unprotected orbits have been ejected from the system. Spectral observations show a reddening in spectral slope with increasing heliocentric distance; it is proposed that this is an evidence that outer-belt asteroids might be primordial objects. 41 refs


    L. Loinard


    Full Text Available Observaciones que utilizan la interferometría de muy larga línea de base (VLBI por sus siglas en ingl´es pueden proveer la posición de radiofuentes compactas con una precisión del orden de 50 micro-segundos de arco. Esto es suficiente para medir la paralaje trigonométrica y los movimientos propios de cualquier objeto localizado hasta 500 pc del Sol con una precisión mejor que unos porcientos. Por ser magnéticamente activas, las estrellas jóvenes a menudo emiten emisión radio compacta detectable usando técnicas VLBI. Aquí, mostraremos cómo observaciones VLBI ya han restringido la distancia a las regiones de formación estelar cercanas más frecuentemente estudiadas (Tauro, Ofiuco, Orión, etc. y han empezado a revelar su estructura y su cinemática interna. Luego, describiremos un gran proyecto (llamado The Gould's Belt Distance Survey diseñado para proveer una vista detallada de la formación estelar en la vecindad Solar, usando observaciones VLBI.

  17. The Pan-African evolution of NW Angola and peri-atlantic correlations

    Monié, P.; Bosch, D.; Bruguier, O.; Vauchez, A.; N'sungani, P.; Rolland, Y.


    At the end of Neoproterozoic times, assembly of the Gondwana supercontinent resulted in the closure of several oceanic domains and accretion of large cratons. Various tectono-metamorphic belts developed at the margins of these cratons during the Panafrican orogeny. During this work, we conducted a study combining petro-structural and geochronological investigations on the West Congolian belt (NW Angola) resulting from the collision between the Congo and Sao Francisco cratons. U-Pb zircon/monazite and Ar-Ar amphibole/biotite ages from high-grade metamorphic rocks, migmatites and metagranites indicate that this area underwent two main deformation events at c. 540 and 490 Ma, which were followed by tectonically assisted exhumation during eastward thrusting of the hinterland domain onto the foreland domain. High grade conditions in the West Congo Belt are 20 to 40 Ma younger than in the Ribeira-Araçuai belt of Brazil, its South-American counterpart, or in the westernmost Kaoko belt of Namibia, its African correlative. In the present state of knowledge, a more appropriate counterpart to the West Congo Belt may be restricted to the Cabo Frio Terrane in the eastern Ribeira belt, which yields a broadly similar evolution.

  18. Feedforward and feedback projections of caudal belt and parabelt areas of auditory cortex: refining the hierarchical model



    Full Text Available Our working model of the primate auditory cortex recognizes three major regions (core, belt, parabelt, subdivided into thirteen areas. The connections between areas are topographically ordered in a manner consistent with information flow along two major anatomical axes: core-belt-parabelt and caudal-rostral. Remarkably, most of the connections supporting this model were revealed using retrograde tracing techniques. Little is known about laminar circuitry, as anterograde tracing of axon terminations has rarely been used. The purpose of the present study was to examine the laminar projections of three areas of auditory cortex, pursuant to analysis of all areas. The selected areas were: middle lateral belt (ML; caudomedial belt (CM; and caudal parabelt (CPB. Injections of anterograde tracers yielded data consistent with major features of our model, and also new findings that compel modifications. Results supporting the model were: 1 feedforward projection from ML and CM terminated in CPB; 2 feedforward projections from ML and CPB terminated in rostral areas of the belt and parabelt; and 3 feedback projections typified inputs to the core region from belt and parabelt. At odds with the model was the convergence of feedforward inputs into rostral medial belt from ML and CPB. This was unexpected since CPB is at a higher stage of the processing hierarchy, with mainly feedback projections to all other belt areas. Lastly, extending the model, feedforward projections from CM, ML, and CPB overlapped in the temporal parietal occipital area (TPO in the superior temporal sulcus, indicating significant auditory influence on sensory processing in this region. The combined results refine our working model and highlight the need to complete studies of the laminar inputs to all areas of auditory cortex. Their documentation is essential for developing informed hypotheses about the neurophysiological influences of inputs to each layer and area.

  19. Is There a Relationship between Family Structure and Substance Use among Public Middle School Students?

    Paxton, Raheem J.; Valois, Robert F.; Drane, J. Wanzer


    We investigated the relationship between family structure and substance use in a sample of 2,138 public middle school students in a southern state. The CDC Middle School Youth Risk Behavior Survey was utilized and adjusted logistic regression models were created separately for four race/gender categories (African American females/males, and…

  20. Seat belts, airbags and child protection devices. [previously: Seat belts and child restraint seats.


    In the Netherlands, the use of seat belts results in a yearly reduction of hundreds of fatalities. Seat belts reduce the risk of fatal injury by 37 to 48%, depending on the position in the car. At 50%, the effect of child protection devices is even slightly higher. When last measured (in 2010), 97%

  1. Analysis of stress distribution of timing belts by FEM; Yugen yosoho ni yoru timing belt oryoku kaiseki (belt code oryoku bunpu kaiseki hokoku)

    Furukawa, Y.; Tomono, K.; Takahashi, H.; Uchida, T. [Honda R and D Co. Ltd., Tokyo (Japan)


    A model of the belt analyzed by-ABAQUS (: a general nonlinear finite element program) successfully confirmed the mechanism that generates the belt cord stress. A quite good agreement between experimental and computed results for the stress distribution of the belt cord. It is found that maximum stress of the cords occurs near the root of the tooth by calculation, where the belt cords break off. 3 refs., 9 figs.

  2. Psychometric evaluations of the efficacy expectations and Outcome Expectations for Exercise Scales in African American women.

    Murrock, Carolyn J; Gary, Faye


    This secondary analysis tested the reliability and validity of the Self-Efficacy for Exercise (SEE) and the Outcome Expectations for Exercise (OEE) scales in 126 community dwelling, middle aged African American women. Social Cognitive Theory postulates self-efficacy is behavior age, gender and culture specific. Therefore, it is important to determine ifself-efficacy scales developed and tested in older Caucasian female adults are reliable and valid in middle aged, minority women. Cronbach's alpha and construct validity using hypothesis testing and confirmatory factor analysis supported the reliability and validity of the SEE and OEE scales in community dwelling, middle aged African American women. PMID:25612395

  3. Thinking about Middle School.

    Hochman, Jere

    This book on middle school uses a very free-form structure to encourage educators to think about middle school's philosophy and purpose, and about how to create a successful middle school. The preface claims that it is not a book "about" teaming, advisory, interdisciplinary units, intramurals, parent-teacher conferences, and other middle school…

  4. African Otter Workshop

    Jan Reed-Smith; Hughes Akpona; Grace Yoxon


    All concerned thought this was an excellent workshop with important progress made towards creating a viable beginning of an African Otter Network. There is a long road ahead but the 2015 African Otter Workshop is a start on developing range country partners, activists and researchers as well as collaborating on issue identification and resolution which will assist in preserving at least some refugia for Africa’s otters. A list of actions was agreed on, including the creation of an African Ott...

  5. African and non-African admixture components in African Americans and an African Caribbean population.

    Murray, Tanda; Beaty, Terri H; Mathias, Rasika A; Rafaels, Nicholas; Grant, Audrey Virginia; Faruque, Mezbah U; Watson, Harold R; Ruczinski, Ingo; Dunston, Georgia M; Barnes, Kathleen C


    Admixture is a potential source of confounding in genetic association studies, so it becomes important to detect and estimate admixture in a sample of unrelated individuals. Populations of African descent in the US and the Caribbean share similar historical backgrounds but the distributions of African admixture may differ. We selected 416 ancestry informative markers (AIMs) to estimate and compare admixture proportions using STRUCTURE in 906 unrelated African Americans (AAs) and 294 Barbadians (ACs) from a study of asthma. This analysis showed AAs on average were 72.5% African, 19.6% European and 8% Asian, while ACs were 77.4% African, 15.9% European, and 6.7% Asian which were significantly different. A principal components analysis based on these AIMs yielded one primary eigenvector that explained 54.04% of the variation and captured a gradient from West African to European admixture. This principal component was highly correlated with African vs. European ancestry as estimated by STRUCTURE (r(2)=0.992, r(2)=0.912, respectively). To investigate other African contributions to African American and Barbadian admixture, we performed PCA on approximately 14,000 (14k) genome-wide SNPs in AAs, ACs, Yorubans, Luhya and Maasai African groups, and estimated genetic distances (F(ST)). We found AAs and ACs were closest genetically (F(ST)=0.008), and both were closer to the Yorubans than the other East African populations. In our sample of individuals of African descent, approximately 400 well-defined AIMs were just as good for detecting substructure as approximately 14,000 random SNPs drawn from a genome-wide panel of markers. PMID:20717976

  6. Paleostructural geomorphology of the Paleozoic central uplift belt and its constraint on the development of depositional facies in the Tarim Basin

    LIN ChangSong; YANG HaiJun; LIU JingYan; PENG Li; CAI ZhenZhong; YANG XiaoFa; YANG YongHeng


    Inclined eastward and consisting of the Hetianhe,Hetianhedong,Tazhong paleouplifts and Bachu pa-leoslope,the central paleouplift belt in the Tarim Basin was a large composite paleouplift and pa-leoslope belt with complicated palaeogeomorphic features during the Middle to early Late Ordovician.A number of paleostructural geomorphic elements have been identified in the paleouplift belt and sur-rounding areas,such as the high uplift belts,the faulted uplift platforms,the marginal slopes and slope break zones flanking the paleouplift belt,the surrounding shelf slopes or low relief ramps,the shelf slope break zones and deep basin plains.They exerted great influence on the development of paleo-geography of the basin.The marginal slopes and slope break zones flanking the uplift belt constrained the formation and deposition of the high-energy facies including reefal and shoal deposits during the Late Ordovician,which comprise the major reservoirs of the Lower Paleozoic in the basin.Toward the end of the Ordovician,the Tazhong paleouplift hinged westward and became a westward-dipped nose as the southeastern margin of the basin was strongly compressed and uplifted.The tec-tono-paleogeomorphic framework of the central northern basin during the Early Silurian and the Late Devonian to Early Carboniferous changed remarkably in topography from the initial low in east and high in west to high in northeast and low in southwest.The major paleogeomorphic elements devel-oped in these periods included the strong eroded uplift high,the uplift marginal slope,the gentle ramp of the depression margin and the depression belt.The sandstones of the Iowstand and the early transgressive systems tracts were deposited along the uplift marginal slopes and the gentle ramps of the depressions comprise the prolific reservoirs in the basin.The study indicates that the distribution patterns of the unconformities within the basin are closely related to the paleogeomorphic features and evolution of the


    Natalia M. Levashova


    Full Text Available The tectonic and paleogeographic evolution of the Ural-Mongol belt between the cratons of Baltica, Siberia, and Tarim is the key to the formation of the Eurasian supercontinent during Paleozoic time, but the views on this complicated process remain very disparate and sometimes controversial. Three volcanic formations of the Middle Silurian, LowertoMiddle Devonian and Middle Devonian age from the southwestern boundary of the Chingiz Range (NE Kazakhstan yields what are interpreted as primary paleomagnetic directions that help clarify the evolution of the belt. A singlepolarity characteristic component in midSilurian andesites yields a positive intraformational conglomerate test, whereas dualpolarity prefolding components are isolated from the two Devonian collections. These new data were evaluated together with previously published paleomagnetic results from Paleozoic rocks in the Chingiz Range, and allow us to establish with confidence the hemisphere in which the area was located at a given time. We conclude that NE Kazakhstan was steadily moving northward crossing the equator in Silurian time. These new paleomagnetic data from the Chingiz range also agree with and reinforce the hypothesis that the strongly curved volcanic belts of Kazakhstan underwent oroclinal bending between Middle Devonian and Late Carboniferous time. A comparison of the Chingiz paleolatitudes with those of Siberia shows similarities between the northward motion and rotational history of the Chingiz unit and those of Siberia, which imposes important constraints on the evolving paleogeography of the Ural-Mongol belt.

  8. The Compositions of Kuiper Belt Objects

    Brown, Michael E


    Objects in the Kuiper belt are small and far away thus difficult to study in detail even with the best telescopes available at earth. For much of the early history of the Kuiper belt, studies of the compositions of these objects were relegated to collections of moderate quality spectral and photometric data that remained difficult to interpret. Much early effort was put into simple correlations of surface colors and identifications of spectral features, but it was difficult to connect the observations to a larger understanding of the region. The last decade, however, has seen a blossoming in our understanding of the compositions of objects in the Kuiper belt. This blossoming is a product of the discoveries of larger -- and thus easier to study -- objects, continued dedication to the collection of a now quite large collection of high quality photometric and spectroscopic observations, and continued work at the laboratory and theoretical level. Today we now know of many processes which affect the surface compos...

  9. Lubricants for Metal Belt Continuously Variable Transmissions

    Keiichi Narita


    Full Text Available This paper reviews the effects of lubricant additives and base stock used in metal belt continuously variable transmissions (CVT fluids on the CVT transmission torque capacity. Additive formulation composed of phosphorus anti-wear agent, calcium detergent, and dispersant improved the friction coefficient between the metals. The analysis on the post-test surface suggests that the friction behavior strongly depends on the local morphology of the tribofilms derived from lubricant additives. Examining the effect of base stock on the torque capacity in actual belt CVTs revealed that SN (synthetic naphthene exhibited 10% higher torque capacity than that of PAO (polyalphaolefin. It is believed that the difference in the torque capacity is due to the difference in the oil-film shearing force generated by the relative sliding between the belt and pulley.

  10. Archaean Crustal Growth, Proterozoic Terrane Amalgamation and the Pan-African Orogeny, as Recorded in the NE African Sedimentary Record.

    Najman, Y.; Fielding, L.; Millar, I.; Butterworth, P.; Andò, S.; Padoan, M.; Barfod, D. N.; Kneller, B. C.


    The cratons of Central Africa are formed of various blocks of Archaean and Palaeoproterozoic crust, flanked or truncated by Palaeoproterozoic to Mesoproterozoic orogenic belts. The geology of east Africa has largely been shaped by the events of the Pan-African Orogeny when east and west Gondwana collided to form 'Greater Gondwana' at the end of the Neoproterozoic. The Pan-African orogeny in NE Africa involved the collision of Archaean cratons and the Saharan Metacraton with the Arabian Nubian Shield, a terrane comprising Neoproterozoic juvenile oceanic island arcs. Phanerozoic cover sedimentary rocks, eroded from the Pan-African orogenies, blanket much of NE Africa. Detrital data from these Phanerozoic cover sedimentary rocks, and modern rivers draining both the cover the basement, provide a wealth of information on basement evolution, of particular relevance for regions where the basement itself is poorly exposed due to ancient or modern sedimentary cover. From samples collected in Uganda, Ethiopia, Sudan and Egypt, we provide combined U-Pb and Hf-isotope zircon, U-Pb rutile and Ar-Ar mica datasets, heavy mineral analyses, and bulk trace element data, from Archaean basement, Phanerozoic cover and modern river sediment from the Nile and its tributaries to document the evolution of the North African crust. The data document early crust-forming events in the Congo Craton and Sahara Metacraton, phased development of the Arabian Nubian Shield culminating in the Neoproterozoic assembly of Gondwana during the Pan African Orogeny, and the orogen's subsequent erosion, with deposition of voluminous Phanerozoic cover.

  11. Two stages of deformation and fluid migration in the central Brooks Range fold-and-thrust belt

    Moore, Thomas E.; Potter, Christopher J.; O'Sullivan, Paul B.; Shelton, Kevin L.; Underwood, Michael B.


    The Brooks Range is a north-directed fold and thrust belt that forms the southern boundary of the North Slope petroleum province in northern Alaska. Field-based studies have long recognized that large-magnitude, thin-skinned folding and thrusting in the Brooks Range occurred during arc-continent collision in the Middle Jurassic to Early Cretaceous (Neocomian). Folds and thrusts, however, also deform middle and Upper Cretaceous strata of the Colville foreland basin and thus record a younger phase of deformation that apatite fission-track data have shown to occur primarily during the early Tertiary (~60 and ~45 Ma). A structural and kinematic model that reconciles these observations is critical to understanding the petroleum system of the Brooks Range fold and thrust belt.

  12. African American men's perspectives on promoting physical activity: "We're not that difficult to figure out!".

    Friedman, Daniela B; Hooker, Steven P; Wilcox, Sara; Burroughs, Ericka L; Rheaume, Carol E


    African American men report poorer health than do White men and have significantly greater odds for developing chronic diseases partly because of limited physical activity. Understanding how to encourage healthy behaviors among African American men will be critical in the development of effective physical activity messages and programs. Guided by principles of cultural sensitivity and social marketing, this research examined middle-aged and older African American men's recommended strategies for promoting physical activity to African American men of their age. The authors report results from 49 interviews conducted with middle-aged (45-64 years) and older (65-84 years) African American men in South Carolina. Four groups of African American men were recruited: middle-aged active men (n = 17), middle-aged inactive men (n = 12), older active men (n = 10), older inactive men (n = 10). Themes related to marketing and recruitment strategies, message content, and spokesperson characteristics emerged and differed by age and physical activity level. Recommended marketing strategies included word of mouth; use of mass media; partnering with churches, businesses, and fraternities; strategic placement of messages; culturally appropriate message framing; and careful attention to selection of program spokespersons. Findings will help in the marketing, design, implementation, and evaluation of culturally appropriate interventions to encourage physical activity among middle-aged and older African American men in the South. PMID:22808914

  13. Sedimentary features and exploration targets of Middle Permian reservoirs in the SW Sichuan Basin

    Guoming Xu


    Full Text Available The exploration direction and targets for the large-scale Middle Permian gas reservoirs in the Sichuan Basin are hot spots and challenges in current exploration researches. The exploration successes of large gas field of Cambrian Longwangmiao Formation in Gaoshiti-Moxi region, Central Sichuan Basin, indicated that prospective sedimentary facies belt was the basis for the formation of large gas fields. In this paper, based on seismic data, outcrop data and drilling data, the tectonic framework and sedimentary features of the Middle Permian in the SW Sichuan Basin were comprehensively studied. The following conclusions were reached from the perspective of sedimentary facies control: (1 during the Middle Permian, this region was in shallow water gentle slope belts with high energy, where thick reef flat facies were deposited; (2 the basement was uplifted during Middle Permian, resulting in the unconformity weathering crust at the top of Maokou Formation due to erosion; the SW Sichuan Basin was located in the karst slope belt, where epigenic karstification was intense; and (3 reef flat deposits superimposed by karst weathering crust was favorable for the formation of large-scale reef flat karst reservoirs. Based on the combination of the resources conditions and hydrocarbon accumulation conditions in this region, it was pointed out that the Middle Permian has great potential of large-scale reef flat karst gas reservoir due to its advantageous geological conditions; the Middle Permian traps with good hydrocarbon accumulation conditions were developed in the Longmen Mountain front closed structural belt in the SW Sichuan Basin and Western Sichuan Basin depression slope belt, which are favorable targets for large-scale reef flat karst reservoirs.

  14. A shell model for tyre belt vibrations

    Lecomte, C.; Graham, W. R.; Dale, M.


    We present a new formulation for the prediction of tyre belt vibrations in the frequency range 0-500 Hz. Our representation includes the effects of belt width, curvature and anisotropy, and also explicitly models the tyre sidewalls. Many of the associated numerical parameters are fixed by physical considerations; the remainder require empirical input. A systematic and general approach to this problem is developed, and illustrated for the specific example of a Goodyear Wrangler tyre. The resulting predictions for the radial response to radial forcing show good correspondence with experiment up to 300 Hz, and satisfactory agreement up to 1 kHz.

  15. Keeping African Masks Real

    Waddington, Susan


    Art is a good place to learn about our multicultural planet, and African masks are prized throughout the world as powerfully expressive artistic images. Unfortunately, multicultural education, especially for young children, can perpetuate stereotypes. Masks taken out of context lose their meaning and the term "African masks" suggests that there is…

  16. Empowering African States


    China helps bring lasting peace and stability to Africa African think tanks expressed a high opinion of China’s role in helping build African peace and security at the first meeting of the China-Africa Think Tanks Forum. The

  17. African Literature as Celebration.

    Achebe, Chinua


    Describes the Igbo tradition of "Mbari," a communal creative enterprise that celebrates the world and the life lived in it through art. Contrasts the cooperative, social dimension of pre-colonial African culture with the exclusion and denial of European colonialism, and sees new African literature again celebrating human presence and dignity. (AF)

  18. Carbon isotope fluctuations and sedimentation age of precambrian marbles of the Serido Belt, northeastern Brazil

    The NNE-trending Serido Belt forms a part of the Borborema tectonostraigraphic terrane in NE Brazil. The Serido Belt (Serido Group) is a supracrustal meta-sedimentary sequence, deposited over an essentially Paleoproterozoic gneissic-migmatite basement (2.23-2.15 Ga, Dantas et al., 1991). They are intruded by Neoproterozoic granites that show geochemical diversity (Jardim de Sa et al. 1987). The Serido Group rocks show evidence of repetitive deformation, intense shearing and high-temperature-low-pressure metamorphism. The Serid Group is subdivided into three units: (1) Jucurutu Fm. (basal unit) composed of para-gneisses with intercalated marble bands and calc-silicatic rocks, (2) Equador Fm. (middle unit) formed by quartzites with conglomerate and para-gneiss interbands and (3) the Serido Fm. (topmost unit) is characterized by predominant micaschist with minor intercalations of marble and calc-silicate rocks. There is no general agreement on the age of these rocks. Augen-orthogneisses (believed to be intrusive into the Serido Group (Jardim de Sa et al.,1995) have yielded zircon U-Pb age of 2.0 to 1.9 Ga (Legrand et al. 1991), implying a minimum age of 2.0-1.9 Ga for the metasedimentary rocks. Such an assumption has, however, been contested by Van Schmus et al. (1996, 2000) on the basis of 1.6 to 1.2 Ga Nd model-age dating of metasediments and 0.65 Ga of detrital zircon (U-Pb) age that proposed a Neoproterozoic age for the Serido Belt. The age controversy of this belt needs an independent approach to resolve this issue. We have initiatated a detailed carbon chemostratigraphic investigation of carbonate rocks of this belt and discuss our findings below (au)

  19. Saturn Neutron Exosphere as Source for Inner and Innermost Radiation Belts

    Cooper, John; Lipatov, Alexander; Sittler, Edward; Sturner, Steven


    Energetic proton and electron measurements by the ongoing Cassini orbiter mission are expanding our knowledge of the highest energy components of the Saturn magnetosphere in the inner radiation belt region after the initial discoveries of these belts by the Pioneer 11 and Voyager 2 missions. Saturn has a neutron exosphere that extends throughout the magnetosphere from the cosmic ray albedo neutron source at the planetary main rings and atmosphere. The neutrons emitted from these sources at energies respectively above 4 and 8 eV escape the Saturn system, while those at lower energies are gravitationally bound. The neutrons undergo beta decay in average times of about 1000 seconds to provide distributed sources of protons and electrons throughout Saturn's magnetosphere with highest injection rates close to the Saturn and ring sources. The competing radiation belt source for energetic electrons is rapid inward diffusion and acceleration of electrons from the middle magnetosphere and beyond. Minimal losses during diffusive transport across the moon orbits, e.g. of Mimas and Enceladus, and local time asymmetries in electron intensity, suggest that drift resonance effects preferentially boost the diffusion rates of electrons from both sources. Energy dependences of longitudinal gradient-curvature drift speeds relative to the icy moons are likely responsible for hemispheric differences (e.g., Mimas, Tethys) in composition and thermal properties as at least partly produced by radiolytic processes. A continuing mystery is the similar radial profiles of lower energy (neutron decay, but perhaps alternatively from atmospheric albedo, or else all protons from diverse distributed sources are similarly affected by losses at the moon' orbits, e.g. because the proton diffusion rates are extremely low. Enceladus cryovolcanism, and radiolytic processing elsewhere on the icy moon and ring surfaces, are additional sources of protons via ionization and charge exchange from breakup of

  20. Geochemical and zircon U-Pb dating analysis of metamagmatic rocks from the Yuli belt in Taiwan

    Hung, Chia-Chia


    The Tananao Schist Complex of the oldest rocks in Taiwan is exposed at the eastern limb of Backbone Range. Based on the lithologic and metamorphic characteristics, the complex can be divided into the Tailuko and Yuli belts. The Tailuko belt consists of marble, gneiss, and subordinate scattered metabasite; the Yuli belt is composed of greenschist, serpentinite, meta-tuff, meta-gabbro, metabasite, and glaucophane-schist blocks which enclosed by spotted schist of the host rocks. The metamorphic belts were inferred as a Mesozoic mélange. It's still controversial due to the difficulty of analyzing metamorphic rocks. In this study, we focus on the zircon U-Pb dating, geochemistry, and petrographic analysis of spotted schist, metabasite, meta-gabbro, and meta-tuff in order to constrain the formation and crystallization ages and interpret its tectonic setting. Based on zircon U-Pb dating, the host rocks of spotted schist and the exotic blocks of meta-tuff, meta-gabbro (the peak age of 14.4, 15.8, and 16.7 Ma), and metabasite occurred at Miocene. Geochemical characteristics for metabasite and meta-gabbro blocks show Ta-Nd-Ti depletion and LREE depletion in spidergram occurring volcanic arc and N-MORB type affinities, respectively. Results as above mentioned, we suggest that the metamagmatic rocks in the Yuli belt occur within a mélange during the Eurasia continental margin subduction at the Middle-Late Miocene.

  1. Albedo Properties of Main Belt Asteroids Based on the Infrared All-Sky Survey of the Astronomical Satellite AKARI

    Usui, Fumihiko; Hasegawa, Sunao; Ishiguro, Masateru; Kuroda, Daisuke; Mueller, Thomas G; Ootsubo, Takafumi; Matsuhara, Hideo


    We present an analysis of the albedo properties of main belt asteroids detected by the All-Sky Survey of the infrared satellite AKARI. The characteristics of 5120 asteroids detected by the survey, including their sizes and albedos, were cataloged in the Asteroid Catalog Using AKARI (AcuA). Size and albedo measurements were based on the Standard Thermal Model, using inputs of infrared fluxes and absolute magnitudes. Main belt asteroids, which account for 4722 of the 5120 AcuA asteroids, have semimajor axes of 2.06 to 3.27 AU. AcuA provides a complete data set of all main belt asteroids brighter than the absolute magnitude of H 20 km. We confirmed that the albedo distribution of the main belt asteroids is strongly bimodal as was already known from the past observations, and that the bimodal distribution occurs not only in the total population, but also within inner, middle, and outer regions of the main belt. We found that the small asteroids have much more variety in albedo than the large asteroids. In spite ...

  2. Timing belts - development, milestones and innovations; Zahnriemen Entwicklungsmeilensteine und Innovationen

    Schulte, H. [Contitech Power Transmission Group (Germany)


    Contitech has much contributed to improve the characteristics of timing belts until today. In this article Contitech introduces some current developments and shows the advantages of belts compared to chain drives. (orig.)

  3. Transpressional granite-emplacement model: Structural and magnetic study of the Pan-African Bandja granitic pluton (West Cameroon)

    Sandjo, A. F. Yakeu; Njanko, T.; Njonfang, E.; Errami, E.; Rochette, P.; Fozing, E.


    The Pan-African NE-SW elongated Bandja granitic pluton, located at the western part of the Pan-African belt in Cameroon, is a K-feldspar megacryst granite. It is emplaced in banded gneiss and its NW border underwent mylonitization. The magmatic foliation shows NE-SW and NNE-SSW strike directions with moderate to strong dip respectively in its northern and central parts. This mostly, ferromagnetic granite displays magnetic fabrics carried by magnetite and characterized by (i) magnetic foliation with best poles at 295/34, 283/33 and 35/59 respectively in its northern, central and southern parts and (ii) a subhorizontal magnetic lineation with best line at 37/8, 191/9 and 267/22 respectively in the northern, central and southern parts. Magnetic lineation shows an `S' shape trend that allows to (1) consider the complete emplacement and deformation of the pluton during the Pan-African D 2 and D 3 events which occurred in the Pan-African belt in Cameroon and (2) reorganize Pan-African ages from Nguiessi Tchakam et al. (1997) compared with those of the other granitic plutons in the belt as: 686 ±17 Ma (Rb/Sr) for D 1 age of metamorphism recorded in gneiss; and the period between 604-557 Ma for D 2-D 3 emplacement and deformation age of the granitic pluton in a dextral ENE-WSW shear movement.

  4. Pervasive Palaeogene remagnetization of the central Taurides fold-and-thrust belt (southern Turkey) and implications for rotations in the Isparta Angle

    Meijers, Maud J. M.; van Hinsbergen, Douwe J. J.; Dekkers, Mark J.; Altıner, Demir; Kaymakcı, Nuretdin; Langereis, Cor G.


    The Turkish Anatolide-Tauride block rifted away from the northern margin of Gondwana in the Triassic, which gave way to the opening of the southern Neo-Tethys. By the late Palaeocene to Eocene, it collided with the southern Eurasian margin, leading to the closure of the northern Neo-Tethys ocean. To determine the position of the Anatolide-Tauride block with respect to the African and Eurasian margin we carried out a palaeomagnetic study in the central Taurides belt, which constitutes the eastern limb of the Isparta Angle. The sampled sections comprise Carboniferous to Palaeocene rocks (mainly limestones). Our data suggest that all sampled rocks are remagnetized during the late Palaeocene to Eocene phase of folding and thrusting event, related to the collision of the Anatolide-Tauride block with Eurasia. To further test the possibility of remagnetization, we use a novel end-member modelling approach on 174 acquired isothermal remanent magnetization (IRM) curves. We argue that the preferred three end-member model confirms the proposed remagnetization of the rocks. Comparing our data to the post-Eocene declination pattern in the central Tauride belt, we conclude that our clockwise rotations are in agreement with data from other studies. After combining our results with previously published data from the Isparta Angle (that includes our study area), we have reasons to cast doubt on the spatial and temporal extent of an earlier reported early to middle Miocene remagnetization event. We argue that the earlier reported remagnetized directions from Triassic rocks—in tilt corrected coordinates—from the southwestern Antalya Nappes (western Taurides), are in good agreement with other studies from the area that show a primary origin of their characteristic remanent magnetization. This implies that we document a clockwise rotation for the southwestern Antalya Nappes since the Triassic that is remarkably similar to the post-Eocene (˜40°) rotation of the central Taurides

  5. Composite Microdiscs with a Magnetic Belt

    Knaapila, Matti; Høyer, Henrik; Helgesen, Geir


    We describe an emulsion-based preparation of patchy composite particles (diameter of 100-500 mu m) consisting of a disclike epoxy core and a belt of porous polystyrene particles (diameter of 30 mu m) with magnetite within the pores. Compared to the magnetically uniform polystyrene particles, the...

  6. Middle ear infection (image)

    A middle ear infection is also known as otitis media. It is one of the most common of childhood infections. With this illness, the middle ear becomes red, swollen, and inflamed because of bacteria ...

  7. Middle Ear Infections

    ... Issues Listen Español Text Size Email Print Share Middle Ear Infections Page Content Article Body What are ... serious illness. What if a child with a middle ear infection is in great pain and discomfort? ...

  8. Imaging Jupiter Radiation Belts At Low Frequencies

    Girard, J. N.; de Pater, I.; Zarka, P.; Santos-Costa, D.; Sault, R.; Hess, S.; Cecconi, B.; Fender, R.; Pewg, Lofar


    The ultra-relativistic electrons, trapped in the inner radiation belts of Jupiter, generates a strong synchrotron radio emission (historically known as the jovian decimeter radiation (DIM)) which is beamed, polarized (~20% linear, ~1% circular) and broadband. It has been extensively observed by radio telescopes/ probes and imaged by radio interferometers over a wide frequency spectrum (from >300 MHz up to 22 GHz). This extended emission presents two main emission peaks constantly located on both sides of the planet close to the magnetic plane. High latitude emissions were also regularly observed at particular frequencies, times and in particular observational configurations. This region of the magnetosphere is "frozen" due to the strong magnetic field (~4.2 G as the equator) and therefore is forced to rotate at the planetary period (T≈9h55m). Due to the tilt (~ 10o) between the spin axis of the planet and the magnetic axis (which can be seen as dipolar in first approximation), the belts and the associated radio emission wobble around the planet center. The analysis of the flux at different frequencies highlighted spatial, temporal and spectral variabilities which origins are now partly understood. The emission varies at different time scales (short-time variations of hours to long-term variation over decades) due to the combination of visibility effect (wobbling, beaming, position of the observer in the magnetic rotating reference frame) [1], [2] and intrinsic local variations (interaction between relativistic electrons and satellites/dust, delayed effect of the solar wind ram pressure, impacts events) [3], [4], [5]. A complete framework is necessary to fully understand the source, loss and transport processes of the electrons originating from outside the belt, migrating by inward diffusion and populating the inner region of the magnetosphere. Only a few and unresolved measurements were made below 300 MHz and the nonsystematic observation of this radio emission

  9. African Peacekeepers in Africa

    Emmanuel, Nikolas G.


    peacekeeping operations in the region. It is important to add that the international community has frequently tried to facilitate the deployment of African armed forces with aid and training. From this reality, the following study goes beyond the current literature by focusing on the international factors...... behind African participation in United Nations (UN) peacekeeping operations in Africa. In doing so, this research focuses on US military aid and foreign troop training from 2002 to 2012, and its impact on African deployments into UN peacekeeping missions in Africa. As can be expected, such third...

  10. Reading the African context

    Musonda Bwalya


    There is so much alienation, pain and suffering in our today�s world. In this vein, African Christianity, a voice amongst many voices, should seek to be a transformational religion for the whole of life, affecting all facets of human life towards a fuller life of all in Africa. This article sought to highlight and point to some of the major societal challenges in the African context which African Christianity, as a life-affirming religion, should continue to embrace, re-embrace and engag...

  11. Capitalism and African business cultures

    Taylor, Scott D.


    Scholars and practitioners once commonly linked 'African culture' to a distinctive 'African capitalism', at odds with genuine capitalism and the demands of modern business. Yet contemporary African business cultures reveal that a capitalist ethos has taken hold within both state and society. The success and visibility of an emergent, and celebrated, class of African big business reveals that business and profit are culturally acceptable. Existing theories of African capitalism are ill-equippe...

  12. Detecting Extrasolar Asteroid Belts Through Their Microlensing Signatures

    Lake, Ethan; Dong, Subo


    We propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called "pseudo-caustics", regions in the source plane where the magnification exhibits a finite but discontinuous jump. These features allow such systems to generate distinctive microlensing light curves across a wide region of belt parameter space and possess remarkably large lensing cross-sections. Sample light curves for a range of asteroid belt parameters are presented. In the near future, space-based microlensing surveys (e.g., WFIRST) may be able to discover extrasolar asteroid belts with masses of the order of $0.1 M_{\\oplus}$.

  13. Middle Ear Infections (For Parents)

    ... Story" 5 Things to Know About Zika & Pregnancy Middle Ear Infections KidsHealth > For Parents > Middle Ear Infections ... eventually leading to an ear infection. continue About Middle Ear Infections Inflammation in the middle ear area ...

  14. Seat Belt Use Among Adult Workers - 21 States, 2013.

    Boal, Winifred L; Li, Jia; Rodriguez-Acosta, Rosa L


    Roadway incidents involving motorized vehicles accounted for 24% of fatal occupational injuries in the United States during 2013 and were the leading cause of fatal injuries among workers.* In 2013, workers' compensation costs for serious, nonfatal injuries among work-related roadway incidents involving motorized land vehicles were estimated at $2.96 billion.(†) Seat belt use is a proven method to reduce injuries to motor vehicle occupants (1). Use of lap/shoulder seat belts reduces the risk for fatal injuries to front seat occupants of cars by 45% and the risk to light truck occupants by 60%.(§) To characterize seat belt use among adult workers by occupational group, CDC analyzed data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) and found that not always using a seat belt was significantly associated with occupational group after controlling for factors known to influence seat belt use. Occupational groups with the highest prevalences of not always using a seat belt included construction and extraction; farming, fishing, and forestry; and installation, maintenance, and repair. To increase seat belt use among persons currently employed, states can enact and enforce primary seat belt laws, employers can set and enforce safety policies requiring seat belt use by all vehicle occupants, and seat belt safety advocates can target interventions to workers in occupational groups with lower reported seat belt use. PMID:27309488


    薛河; 苏清祖; 马胜利


    The double drum drive is widely used on the mine belt conveyor, which are divided the rigid connected double drums and separately driving double drums according to connected method of two drums. Because of the change of real work condition, the load distribution is changed on the two drive drums, which may produce a slippage between a drum and belt. Slippage may intensify the wear of the drum, and sometimes causing the fire of the belt. This restricts the development toward narrow belt, high velocity and large power of belt conveyor. In this paper, the factors affecting the load distribution of two drums of double drum belt conveyor are'systematically analyzed and some computing formulas derived, by these formulas, the actual load distribution onthe two drums of rigid connected or separately driving belt conveyor can be separately calculated. These formulas also can be as the theory base for adjusting the driving force of two drums.

  16. The Color Differences of Kuiper Belt Objects in Resonance with Neptune

    Sheppard, Scott S


    (Abridged) New optical colors of 58 objects in mean motion resonances with Neptune show the various resonant populations have significantly different color distributions. The 5:3 and 7:4 resonances have semi-major axes near the middle of the main Kuiper Belt and both are dominated by ultra-red material. The 5:3 and 7:4 resonances have statistically the same color distribution as the low inclination "cold" classical belt. The inner 4:3 and distant 5:2 resonances have objects with mostly moderately red colors, similar to the scattered and detached disk populations. The 2:1 resonance, which is near the outer edge of the main Kuiper Belt, has a large range of colors with similar numbers of moderately red and ultra-red objects at all inclinations. The inner 3:2 resonance, like the outer 2:1, has a large range of objects from neutral to ultra-red. The Neptune Trojans (1:1 resonance) are only slightly red, similar to the Jupiter Trojans. The inner 5:4 resonance only has four objects with measured colors but shows eq...

  17. A six-part collisional model of the main asteroid belt

    Cibulková, Helena; Benavidez, Paula G


    In this work, we construct a new model for the collisional evolution of the main asteroid belt. Our goals are to test the scaling law of Benz and Asphaug (1999) and ascertain if it can be used for the whole belt. We want to find initial size-frequency distributions (SFDs) for the considered six parts of the belt (inner, middle, 'pristine', outer, Cybele zone, high-inclination region) and to verify if the number of synthetic asteroid families created during the simulation matches the number of observed families as well. We used new observational data from the WISE satellite (Masiero et al., 2011) to construct the observed SFDs. We simulate mutual collisions of asteroids with a modified version of the Boulder code (Morbidelli et al., 2009), where the results of hydrodynamic (SPH) simulations of Durda et al. (2007) and Benavidez et al. (2012) are included. Because material characteristics can significantly affect breakups, we created two models - for monolithic asteroids and for rubble-piles. To explain the obse...

  18. Geometry and Kinematics of the Lamu Basin Deep-Water Fold-and-Thrust Belt (East Africa)

    Barchi, Massimiliano R.; Cruciani, Francesco; Porreca, Massimiliano


    Even if most thin-skinned fold-and-thrust belt are generated at convergent plate boundaries, in the last decades advances in seismic exploration and acquisition of large datasets have shown that they are also notably widespread along continental passive margins, driven by gravity processes in deep-water areas. In this study a composite set of modern and vintage reprocessed seismic reflection profiles is used to investigate the internal structure and kinematic evolution of the Lamu Basin Deep-Water Fold-and-Trust Belt (DW-FTB). The Lamu Basin is an example of giant-scale, gravity driven compressional belt developed in Late Cretaceous-Early Tertiary along a still poorly explored sector of the East-African continental margin, at the Kenya-Somalia border. The compressional domain extends longitudinally for more than 450 km, is up to 180 km wide and shows remarkable structural complexity both along strike and along dip. The external part is dominated by ocean-verging imbricate thrusts, above a gently landward-dipping basal detachment. The internal part is characterised by almost symmetrical detachment folds and double verging structures, sustaining bowl-shaped syn-tectonic basins. Here the basal detachment surface is almost flat. The mean fold wavelength displays a progressive landward increase, from 2.5 km, at the toe of the belt, to about 10 km. This structural variability is thought to be related to the lateral variation of the section under shortening and particularly to the different thickness of the Early Cretaceous shaly unit involved in the deformations, increasing landward from about 400 m to more than 1 km. Through the sequential restoration of regional cross-sections, we evaluated that the northern portion of the thrust belt experienced a shortening of almost 50 km (corresponding to 20%), with a shortening rate (during the Late Cretaceous-Paleocene main event) of about 3.5 mm/yr. Under many respects, the dimensions and internal structure of this thrust belt

  19. The scramble for Africans: demography, globalisation and Africa’s informal labour markets

    Meagher, Kate


    Images of an 'African Boom' have presented us with labour markets full of dynamic potential: a declining dependency ratio, low levels of unemployment, and a vibrant middle class. This buoyant view of African labour markets conceals a less encouraging reality of catastrophic youth unemployment and expanding informality, creating a 'youth bulge' that is more of a threat than an opportunity. How does the continent with the largest share of informal labour in the world become a beacon of prosperi...

  20. Ionic composition of the earth's radiation belts

    Spjeldvik, W. N.


    Several different ion species have been positively identified in the earth's radiation belts. Besides protons, there are substantial fluxes of helium, carbon and oxygen ions, and there are measurable quantities of even heavier ions. European, American and Soviet space experimenters have reported ion composition measurements over wide ranges of energies: at tens of keV (ring-current energies) and below, and at hundreds of keV and above. There is still a gap in the energy coverage from several tens to several hundreds of keV where little observational data are available. In this review emphasis is placed on the radiation belt ionic structure above 100 keV. Both quiet time conditions and geomagnetic storm periods are considered, and comparison of the available space observations is made with theoretical analysis of geomagnetically trapped ion spatial, energy and charge state distributions.

  1. A belted kingfisher flies above KSC


    A belted kingfisher soars over the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The pigeon-sized, blue-gray male is identified by the blue-gray breast band; females show a chestnut belly band. The belted kingfisher ranges throughout the United States and Canada, wintering south to Panama and the West Indies. They dive into the water for fish and may also take crabs, crayfish, salamanders, lizards, mice and insects. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

  2. Virtual Universities for African and Arab Countries

    Wolfram LAASER


    Full Text Available Internet development in Africa is constrained by poor telephone infrastructure, low international bandwidth and high dials up tariffs levied on internet users. This means in Africa we find actually app. 1% of worldwide internet users whereas population share of world population may be around 13%. Nearly half of the internet users are concentrated in South Africa. Another one percent of world users is located in the Middle East. Therefore it is understandable that Africa and the Arab world are latecomers in developing net based educational systems. However today donor organizations put strong emphasis on creating Virtual Campuses for African States (EC, Word Bank and Mediterranean countries or plan to incorporate selected African States to other institutional arrangements (Commonwealth of Nations, UNESCO. In what follows we will discuss five of these projects differing in scope, structure and funding namely the Virtual African University, the Avicenna Project, the Virtual Arab University, the Syrian Open University and the proposal for a Virtual University for the Small States. From the analysis of the respective projects some tentative conclusions will be derived.

  3. Alien Asteroid Belt Compared to our Own


    [figure removed for brevity, see original site] Figure 1: Band of Light Comparison This artist's concept illustrates what the night sky might look like from a hypothetical alien planet in a star system with an asteroid belt 25 times as massive as the one in our own solar system (alien system above, ours below; see Figure 1). NASA's Spitzer Space Telescope found evidence for such a belt around the nearby star called HD 69830, when its infrared eyes spotted dust, presumably from asteroids banging together. The telescope did not find any evidence for a planet in the system, but astronomers speculate one or more may be present. The movie begins at dusk on the imaginary world, when HD 69830, like our Sun, has begun to set over the horizon. Time is sped up to show the onset of night and the appearance of a brilliant band of light. This light comes from dust in a massive asteroid belt, which scatters sunlight. In our solar system, anybody observing the skies on a moonless night far from city lights can see the sunlight that is scattered by dust in our asteroid belt. Called zodiacal light and sometimes the 'false dawn,' this light appears as a dim band stretching up from the horizon when the Sun is about to rise or set. The light is faint enough that the disk of our Milky Way galaxy remains the most prominent feature in the sky. (The Milky Way disk is shown perpendicular to the zodiacal light in both pictures.) In contrast, the zodiacal light in the HD 69830 system would be 1,000 times brighter than our own, outshining even the Milky Way.

  4. The East African rift system

    Chorowicz, Jean


    ), its almost 1000 km diameter panache weakening the lithosphere and preparing the later first rifting episode along a preexisting weak zone, a Pan-African suture zone bordering the future Afar region. From the Afar, the rift propagated afterward from north to south on the whole, with steps of local lithospheric failure nucleations along preexisting weak zones. These predisposed lines are mainly suture zones, in which partial activation of low angle detachment faults reworked former thrust faults verging in opposite directions, belonging to double verging ancient belts. This is responsible for eventual reversal in rift asymmetry from one basin to the next. Supposing the plume migrated southward, or other plumes emplaced, the rift could propagate following former weaknesses, even outside areas influenced by plumes. This view of rift formation reconciles the classical models: active plume effect triggered the first ruptures; passive propagations of failure along lithospheric scale weak zones were responsible for the onset of the main rift segments. Various other aspects are shortly considered, such as tectonics and sedimentation, and relationships of the 'cradle of Mankind' with human evolution. By its size, structure and occurrence of oceanic lithosphere in the Afar, the EARS can be taken as a model of the prelude of oceanic opening inside a continent.

  5. Understanding quaternions and the Dirac belt trick

    The Dirac belt trick is often employed in physics classrooms to show that a 2π rotation is not topologically equivalent to the absence of rotation whereas a 4π rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors has been achieved, or if the trick is just an amusing analogy. The goal of this paper is to demystify the belt trick and to show that it suggests an underlying four-dimensional parameter space for rotations that is simply connected. An investigation into the geometry of this four-dimensional space leads directly to the system of quaternions, and to an interpretation of three-dimensional vectors as the generators of rotations in this larger four-dimensional world. The paper also shows why quaternions are the natural extension of complex numbers to four dimensions. The level of the paper is suitable for undergraduate students of physics.

  6. The atmospheric implications of radiation belt remediation

    C. J. Rodger


    Full Text Available High altitude nuclear explosions (HANEs and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1 MeV trapped electron fluxes can shorten the operational lifetime of low Earth orbiting satellites, threatening a large, valuable population. Therefore, studies are being undertaken to bring about practical human control of the radiation belts, termed "Radiation Belt Remediation" (RBR. Here we consider the upper atmospheric consequences of an RBR system operating over either 1 or 10 days. The RBR-forced neutral chemistry changes, leading to NOx enhancements and Ox depletions, are significant during the timescale of the precipitation but are generally not long-lasting. The magnitudes, time-scales, and altitudes of these changes are no more significant than those observed during large solar proton events. In contrast, RBR-operation will lead to unusually intense HF blackouts for about the first half of the operation time, producing large scale disruptions to radio communication and navigation systems. While the neutral atmosphere changes are not particularly important, HF disruptions could be an important area for policy makers to consider, particularly for the remediation of natural injections.

  7. Substyles of belting: phonatory and resonatory characteristics.

    Sundberg, Johan; Thalén, Margareta; Popeil, Lisa


    Belting has been described as speechlike, yell-like, or shouting voice production commonly used in contemporary commercial music genres and substantially differing from the esthetic of the Western classical voice tradition. This investigation attempts to describe phonation and resonance characteristics of different substyles of belting (heavy, brassy, ringy, nasal, and speechlike) and the classical style. A professional singer and voice teacher, skilled in these genres, served as the single subject. The recorded material was found representative according to a classification test performed by an expert panel. Subglottal pressure was measured as the oral pressure during the occlusion for the consonant /p/. The voice source and formant frequencies were analyzed by inverse filtering the audio signal. The subglottal pressure and measured flow glottogram parameters differed clearly between the styles heavy and classical assuming opposite extremes in most parameters. The formant frequencies, by contrast, showed fewer less systematic differences between the substyles but were clearly separated from the classical style with regard to the first formant. Thus, the differences between the belting substyles mainly concerned the voice source. PMID:21439776

  8. Araguaia fold belt, new geochronological data

    The northern part of the Araguaia Fold Belt (AFB) outcrops in a N-S direction for about 400 km in the state of Tocantins. Dome-like structures occur in this fold belt also in a N-S direction. Both deformation and metamorphism increase from the West to the East. The basement of the AFB consist of Colmeia complex and Cantao gneiss, which crop out mainly in the core of the dome-like structures. The supracrustals rocks of the fold belt belongs to the Baixo Araguaia supergroup which is divided into the lower Estrondo group and the upper Tocantins group. Preliminary Sm-Nd data from the Colmeia complex (Grota Rica dome) gave Archean model ages of 2.8 Ga (TNd sub(DM)) while Rb-Sr data in the same rocks give an age of 2530 ± 200 Ma. In the others dome-like structures, the Rb-Sr systematics gave ages for the Colmeia a complex of 2239 ± 47 Ma (Colmeia structure) and 1972 ± 46 Ma (Lontra structure). These younger ages are believed to represent partial to total isotopic resetting of the Rb-Sr system during the Transamazonian Event. The Rb-Sr studies of the Cantao gneiss gave an age of 1774 ± 31 Ma. (author)

  9. Seat belt use during pregnancy in Iran: attitudes and practices

    Mojgan Karbakhsh; Zahra Ershadi; Ali Khaji; Fatemeh Rahimi-Sharbaf


    Objective: Seat belt use during pregnancy reduces injury to the mother and her fetus. During recent years, the use of seat belts has been mandated by law in Iran. The purpose of this study was to determine the attitudes and practices of pregnant women regarding seat belt use.Methods: In this cross-sectional study, we asked 335 pregnant women at a hospital-based prenatal care clinic on the use of safety belt before and during pregnancy. SPSS version 13.0 was used for data analysis.Results: The mean age of study subjects was 27.3 years±5.3 years with the median of 27 years. Compared with the seat belt use before pregnancy, no change was detected in 48.7% of the women; seat belt use had increased in 17.5 %of them and decreased in 33.8 %. Eighty-one percent of women knew the correct placing of both lap belt and shoulder belt. Only 4% of women had received education on proper restraint use during pregnancy.Conclusions: The prevalence of seat belt use during pregnancy is lower than reports which are mostly from developed nations. The fact that about one-third of women have decreased their seat belt usage during pregnancy highlights the importance of education of mothers on this topic.

  10. Human-Related Forest Fires in the Subalpine Belt of the Spanish Pyrenees

    Sanjuán, Yasmina; María García-Ruiz, José; Beguería, Santiago; Serrano-Muela, María Pilar; González-Sampériz, Penélope; Valero-Garcés, Blas; Arnáez, José


    The subalpine belt of the Central Pyrenees ranges approximately between 1700 and 2200 m a.s.l. This area should be covered with dense forests of Pinus sylvestris and P. uncinata, with increasingly open formations towards the upper forest limit. At present, most of the subalpine belt is occupied with grasslands due to human-induced deforestation for enlarging the area occupied by summer pastures. Two are the most important scientific problems related to deforestation of the subalpine belt: (i) the timing of deforestation, and (ii) the geomorphic consequences of a sudden substitution of forests by grasslands. Up to now, intense deforestation is clearly recorded in regional palaeoenvironmental sequences since the Middle Ages and, traditionally, this practice was usually attributed to large fires with the purpose of balance the winter and summer pasture resources. Nevertheless, the presence of abundant remnants of prehistoric monuments (dolmens, cromlechs, tumulus) in the subalpine belt induced to think in a previous seasonal presence of human populations, most probably practicing some primitive type of transhumance. This would only be possible if part of the subalpine forests would be burnt to allow a limited expansion of grasslands, despite the consequences in the landscape of this kind of practices were not permanent in time. We present here new dates of fire occurrence from charcoal obtained from soils in the hillslopes and from lacustrine sediments. Two periods of human-induced fires have been identified: (i) between 2500 and 2000 cal. yr BP, and (ii) between 1100 and 900 cal yr BP. The consequences of deforestation can be easily observed in the landscape, particularly shallow landslide activity, gelifluction, solifluction and the rapid development of parallel incisions in the steepest slopes.

  11. A remarkable illaenid trilobite from the Middle Ordovician of Morocco

    Rábano, I.; Gutiérrez-Marco, J. C.; García-Bellido, D.C.


    Illaenid trilobites were relatively scarce in south-polar peri-Gondwanan areas during the Ordovician, with all their African occurrences restricted to the Middle and Upper Ordovician of Morocco. At a specific level, only the Bohemian form Ectillaenus benignensis (Novák) has been positively identified from the Middle Ordovician of that region. In the present work we add the discovery of the new form Caudillaenus nicolasi gen. et sp. nov., occurring in a single bed of late Darriwilian 2 age wit...

  12. Mental illness and lost income among adult South Africans

    Lund, Crick; Myer, Landon; Dan J Stein; Williams, David R.; Flisher, Alan J


    Purpose Little is known regarding the links between mental disorder and lost income in low- and middle-income countries. The purpose of this study was to investigate the association between mental disorder and lost income in the first nationally representative psychiatric epidemiology survey in South Africa. Methods A probability sample of South African adults was administered the World Health Organization Composite International Diagnostic Interview schedule to assess the presence of mental ...

  13. Fostering a Middle Class



    Though there is no official definition of "middle class" in China,the tag has become one few Chinese people believe they deserve anyway.In early August,the Chinese Academy of Social Sciences released a report on China's urban development,saying China had a middle-class population of 230 million in 2009,or 37 percent of its urban residents.It also forecast half of city dwellers in China would be part of the middle class by 2023.

  14. School Adjustment and the Academic Success of Rural African American Early Adolescents in the Deep South

    Leung, M.-C.


    Full Text Available This study examined the relationship between end-of-year grades and the academic, behavioral, and social characteristics of rural African American youth. Participants included 392 7th and 8th grade students from 2 rural middle schools in the south. Participants were African American and were from 2 communities that have child poverty rates exceeding 50% for public school students. Girls were more likely to have positive characteristics than boys. Academic, behavioral, and social difficulties were linked to low end-of-year grades, and positive characteristics were linked to high grades. Implications for supporting low-achieving African American students from low-resource communities are discussed.

  15. Polycyclic orogeny in Central Ogcheon metamorphic belt, Korea: evidence from 40Ar/39Ar hornblende ages

    Full text: The Ogcheon fold-thrust belt is one of the key Phanerozoic belts for delineating the regional correlation in East Asia including mainland China and Japan. This NE-trending belt consists of the Ogcheon metamorphic belt (OMB) in the southwest and the Taebaeksan sedimentary zone in the northeast. The OMB comprises Late (?) Proterozoic to Paleozoic metasedimentary and metavolcanic sequences intruded by Mesozoic granitoids. The age of initial intracontinental rifting is constrained to be earlier than 756 Ma by the U-Pb zircon age of a felsic metavolcanic rock (Lee et al., 1998, Precamb. Res. 89, 47-57). Polyphase tectonism in the OMB is characterised by the Middle Paleozoic Ogcheon orogeny responsible for the ductile stacking of thrust nappes and the Triassic Songrim orogeny occurring at shallower depths under the brittle-ductile transitional regime (Cluzel et al., 1990, Tectonophysics, 183, 41-56). Peak metamorphic conditions of the former are in the range of 5-8 kbar and 520-590 deg C, whereas those of the latter are 1-3 kbar and 350-500 deg C (Min and Cho, 1998, Lithos, 43, 31-51). Major ambiguity in the polycyclic model of the OMB results from the lack of isotopic age data. In order to determine the age of peak metamorphism, we analysed hornblende crystals of quartzose amphibole schists in central OMB, using the 40Ar/39Ar dating technique. Mineral assemblages of amphibole schists are represented by calcic amphiboles + plagioclase + epidote ± garnet + quartz + titanite + Fe-Ti oxide (magnetite or ilmenite). Amphibole separates commonly display discordant age spectra. Nevertheless, amphiboles of five analysed samples yield 40Ar/39Ar intercept dates ranging from 432±4 Ma to 499±10 Ma. Three of them yield plateau dates of 440-492 Ma, defined by more than three contiguous steps accounting for >50% of the total 39ArK released. Two of these plateau dates (465±4 Ma and 492±4 Ma) are from hornblende fractions of different grain size in a garnet

  16. Characterizing the admixed African ancestry of African Americans

    Zakharia, Fouad; Basu, Analabha; Absher, Devin; Assimes, Themistocles L.; Go, Alan S.; Hlatky, Mark A.; Iribarren, Carlos; Knowles, Joshua W.; Li, Jun; Narasimhan, Balasubramanian; Sidney, Steven; Southwick, Audrey; Myers, Richard M.; Quertermous, Thomas; Risch, Neil


    Abstract Background Accurate, high-throughput genotyping allows the fine characterization of genetic ancestry. Here we applied recently developed statistical and computational techniques to the question of African ancestry in African Americans by using data on more than 450,000 single-nucleotide polymorphisms (SNPs) genotyped in 94 Africans of diverse geographic origins included in the...

  17. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: an important control on shelf mud belts?

    Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.


    Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9–33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9–16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9–16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This “updraft” event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.

  18. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: An important control on shelf mud belts?

    Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.


    Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9-33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9-16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9-16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This "updraft" event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.

  19. North African Jewish and non-Jewish populations form distinctive, orthogonal clusters.

    Campbell, Christopher L; Palamara, Pier F; Dubrovsky, Maya; Botigué, Laura R; Fellous, Marc; Atzmon, Gil; Oddoux, Carole; Pearlman, Alexander; Hao, Li; Henn, Brenna M; Burns, Edward; Bustamante, Carlos D; Comas, David; Friedman, Eitan; Pe'er, Itsik; Ostrer, Harry


    North African Jews constitute the second largest Jewish Diaspora group. However, their relatedness to each other; to European, Middle Eastern, and other Jewish Diaspora groups; and to their former North African non-Jewish neighbors has not been well defined. Here, genome-wide analysis of five North African Jewish groups (Moroccan, Algerian, Tunisian, Djerban, and Libyan) and comparison with other Jewish and non-Jewish groups demonstrated distinctive North African Jewish population clusters with proximity to other Jewish populations and variable degrees of Middle Eastern, European, and North African admixture. Two major subgroups were identified by principal component, neighbor joining tree, and identity-by-descent analysis-Moroccan/Algerian and Djerban/Libyan-that varied in their degree of European admixture. These populations showed a high degree of endogamy and were part of a larger Ashkenazi and Sephardic Jewish group. By principal component analysis, these North African groups were orthogonal to contemporary populations from North and South Morocco, Western Sahara, Tunisia, Libya, and Egypt. Thus, this study is compatible with the history of North African Jews-founding during Classical Antiquity with proselytism of local populations, followed by genetic isolation with the rise of Christianity and then Islam, and admixture following the emigration of Sephardic Jews during the Inquisition. PMID:22869716

  20. Portfolio allocations in the Middle East and North Africa

    Thomas Lagoarde-Segot; Brian M. Lucey


    We examine the issue of possible portfolio diversification benefits into seven Middle-Eastern and North African (MENA) stock markets. We construct international portfolios in dollars and local currencies. We compute the ex-ante weights by plugging five optimization models and two risk measures into a rolling block-bootstrap methodology. This allows us to derive 48 monthly rebalanced ex-post portfolio returns. We analyze the out-of-sample performance based on Sharpe and Sortino ratios and the ...

  1. Economic Research on the Arab world and the Middle East

    Wippel, Steffen


    The article gives an overview of the Development of contemporary research on Middle Eastern and North African economies in Germany. It includes the most important institutions and central research topics and approaches, underlining that this field is, in fact, multidisciplinary. The article also...... points out some of its most salient structural, conceptual, and methodological problems. Referring to research on regionalization processes, the author advocates an open, transregional and transdisciplinary approach closely based on empirical findings....

  2. African-Americans and Alzheimer's

    ... Share Plus on Google Plus African-Americans and Alzheimer's | IHaveAlz Introduction 10 Warning Signs Brain ... African-Americans are at a higher risk for Alzheimer's disease. Many Americans dismiss the warning signs of ...

  3. African American Men’s Perspectives on Promoting Physical Activity: “We’re Not That Difficult to Figure out!”

    Friedman, Daniela B.; Hooker, Steven P.; Wilcox, Sara; Burroughs, Ericka L.; Rheaume, Carol E.


    African American men report poorer health than do White men and have significantly greater odds for developing chronic diseases partly because of limited physical activity. Understanding how to encourage healthy behaviors among African American men will be critical in the development of effective physical activity messages and programs. Guided by principles of cultural sensitivity and social marketing, this research examined middle-aged and older African American men’s recommended strategies ...

  4. Shoshonitic intrusion magmatism in Pajeu-Paraiba belt: the Bom Jardim complex

    The Bom Jardim complex is a multi phase intrusion emplaced within the basement of the Pajeu-Paraiba belt, in the Borborema province, N.E., Brazil, during the Pan African (Brasiliano) orogeny, 600 Ma ago. The Bom Jardim complex is primarily composed of monzonites and syenites with subordinated granites. The major and trace elements geochemistry has established a shoshonitic affinity for the monzonite-syenite assemblages, whereas the granites are clearly of a high-K calc-alkaline character. The main geochemical trends determined for the complex are the result of fractionation of mainly amphibole, biotite, alkali feldspar ±clinopyroxene within the developing magmas. The enrichment in transition metal elements, LILE and high LILE/HSFE ratios, coupled with an initial Sr sup(87)/Sr sup(86) ratio of 0.70709 is consistent with a subduction related magma source. (author)

  5. African Cultural Astronomy

    Holbrook, Jarita C; Medupe, R. Thebe; Current Archaeoastronomy and Ethnoastronomy research in Africa


    Astronomy is the science of studying the sky using telescopes and light collectors such as photographic plates or CCD detectors. However, people have always studied the sky and continue to study the sky without the aid of instruments this is the realm of cultural astronomy. This is the first scholarly collection of articles focused on the cultural astronomy of Africans. It weaves together astronomy, anthropology, and Africa. The volume includes African myths and legends about the sky, alignments to celestial bodies found at archaeological sites and at places of worship, rock art with celestial imagery, and scientific thinking revealed in local astronomy traditions including ethnomathematics and the creation of calendars. Authors include astronomers Kim Malville, Johnson Urama, and Thebe Medupe; archaeologist Felix Chami, and geographer Michael Bonine, and many new authors. As an emerging subfield of cultural astronomy, African cultural astronomy researchers are focused on training students specifically for do...

  6. Health Monitoring for Coated Steel Belts in an Elevator System

    Yimei Mao; Zuoying Huang; Guiyun Tian; Hui Zhao; Huaming Lei


    This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of ...

  7. Device for continuous tare measurement at belt weighers

    The described device can be used for belt weighers connected with a computing unit. Its development has been aimed at measuring the weight of the belt without standstill. This could be achieved by arranging radiation sources and detectors over the whole width of the belt and transforming the radiation attenuation into weight equivalents with the aid of an evaluation unit connected to the computing unit

  8. African names for American plants

    Andel, van T.R.


    African slaves brought plant knowledge to the New World, sometimes applying it to related plants they found there and sometimes bringing Old World plants with them. By tracing the linguistic parallels between names for plants in African languages and in communities descended from African slaves, pie

  9. The Struggles over African Languages

    Maseko, Pam; Vale, Peter


    In this interview, African Language expert Pam Maseko speaks of her own background and her first encounter with culture outside of her mother tongue, isiXhosa. A statistical breakdown of South African languages is provided as background. She discusses Western (originally missionary) codification of African languages and suggests that this approach…

  10. Car safety belts: a study of two models adapted for people with arthritis.

    Arie, E


    People with arthritis find car seat belts difficult to use. Sixteen arthritic patients and 19 healthy volunteers completed a comparative study of one standard inertia-reel belt and two adapted inertia-reel belts with reduced retraction forces. Those with arthritis were strong enough to use the standard belt but both adapted belts had features making them easier to use. PMID:3708235