Science.gov

Sample records for ivory coast tektites

  1. New data on selected Ivory Coast tektites

    USGS Publications Warehouse

    Cuttitta, F.; Carron, M.K.; Annell, C.S.

    1972-01-01

    Fourteen Ivory Coast tektites exhibit a range of bulk indices of refraction of 1.5156 to 1.5217 ?? 0.0004 and of bulk specific gravities of 2.428 to 2.502 ??0.005. Seven of these Ivory Coast (IVC) tektites were analyzed for major and minor element content. Compared to tektites from other strewn fields, their SiO2 content is low (67.2-69.1 %), A12O3 relatively high (15.8-16.8 %), and total iron relatively high but with a more restricted range (6.3-6.8 % as FeO). Their lime content is low (0.71-1.35%) compared to Australasian tektites but their MgO CaO ratio (about 3.1) is unusually high. All other tektite groups have Na2O K2O ratios less than unity, but the Na2O K2O ratio of the IVC tektites is slightly greater than unity. Their K Rb ratios range from 200 to 256 and average 227, which is higher than those determined for Australasian tektites, but similar to some obtained for moldavites. The Li content (41-48 ppm) is about the same as that of the Australasian tektites, but the Cs and Rb are lower, being 1.9 to 2.9 and 57 to 86 ppm, respectively. The IVC tektites are high in Cr (260-375 ppm), Co (19-25 ppm) and Ni (101-167 ppm), and particularly in Pb (<10-18 ppm), Cu (13-21 ppm) and Ga (14-23 ppm). The high Cr Ni ratios of the IVC tektites (range 2-3.6) are similar to those found for australites, philippinites and thailandites, but not the javanites and indochinites. Evaluation of these and other reported data show that compositional similarities between the IVC tektites and green or black Bosumtwi Crater glasses strongly support the hypothesis of a common impact origin-i.e. the Bosumtwi Crater site. Comparison of the IVC tektite composition with those of returned lunar materials (gabbros, basalts, breccia and soils) do not support a lunar origin for the Ivory Coast tektites. ?? 1972.

  2. New data on selected Ivory Coast tektites.

    NASA Technical Reports Server (NTRS)

    Cuttitta, F.; Carron, M. K.; Annell, C. S.

    1972-01-01

    Fourteen Ivory Coast tektites exhibit a range of bulk indices of refraction of 1.5156 to 1.5217 plus or minus 0.0004 and of bulk specific gravities of 2.428 to 2.502 plus or minus 0.005. Seven of these Ivory Coast (IVC) tektites were analyzed for major and minor element content. Compared to tektites from other strewn fields, their SiO2 content is low (67.2-69.1%), Al2O3 relatively high (15.8-16.8%), and total iron relatively high but with a more restricted range (6.3-6.8% as FeO). Their lime content is low (0.71-1.35%) compared to Australasian tektites but their MgO/CaO ratio (about 3.1) is unusually high. All other tektite groups have Na2O/K2O ratios less than unity, but the Na2O/K2O ratio of the IVC tektites is slightly greater than unity. Their K/Rb ratios range from 200 to 256 and average 227.

  3. Oxygen isotopes as tracers of tektite source rocks: An example from the Ivory Coast tektites and Lake Bosumtwi Crater

    NASA Technical Reports Server (NTRS)

    Blum, Joel D.; Koeberl, Christian; Chamberlain, C. Page

    1993-01-01

    Oxygen isotope studies of tektites and impact glasses provide an important tool to help in identifying the target lithologies for terrestrial impacts, including the K-T boundary impact. However, such studies may be complicated by modification of the original oxygen isotope values of some source rocks during the tektite formation process either by vapor fractionation or incorporation of meteoric water. To further investigate the relationship between the oxygen isotopic composition of tektites and their source rocks, Ivory Coast tektites and samples of impact glasses and bedrock lithologies from the Bosumtwi Crater in Ghana--which is widely believed to be the source crater for the Ivory Coast tektites--were studied. Our preliminary results suggest that the phyllites and metagraywackes from the Bosumtwi Crater were the predominant source materials for the impact glasses and tektites and that no significant oxygen isotope modification (less than 1 percent delta(O-18)) took place during impact melting. This contrasts with previous studies of moldavites and Australasian tektites and their sedimentary source materials which suggests a 4 to 5 percent lowering of delta(O-18) due to meteoric water incorporation during impact melting.

  4. Osmium isotopes in Ivory Coast tektites: Confirmation of a meteoritic component and rhenium depletion

    NASA Technical Reports Server (NTRS)

    Koeberl, Christian; Shirey, Steven B.

    1993-01-01

    The sensitive negative thermal ionization mass spectrometry method was used for the measurement of concentrations and isotopic ratios of osmium and rhenium in four Ivory Coast tektites. These tektites have crustal major and trace element composition, as well as large negative epsilon(sub Nd)(-20) and positive epsilon(sub Sr)(+260 to +300) which are characteristic for old continental crust. Os concentrations ranging from 0.09 to 0.30 ppb were found, clearly much higher than average crustal values, Os-187/Os-186 ratios of about 1.2-1.7, and low Re-187/Os-186 ratios. These results show unambiguously the existence of a meteoritic component (on the order of 0.06%) in the Ivory Coast tektites. Low Re abundances are the result of fractionation of Re during the impact.

  5. Trace Elements in Ivory Coast Tektites, Microtektites, and Fallback Particles of the Lake Bosumtwi Impact Crater, Ghana: A LA-ICP-MS Study

    NASA Astrophysics Data System (ADS)

    Luetke, S.; Deutsch, A.; Berndt, J.; Langenhorst, F.

    2008-03-01

    LA-ICP-MS trace element data of Ivory Coast tektites, microtektites, and glassy fallback particles indicate a soil contribution to the precursor materials of the tektites. A variable Ni/Co ratio seems to be characteristic of the fallback particles.

  6. Ivory Coast.

    PubMed

    1985-07-01

    Since the Ivory Coast's independence (1960), the population has increased from 3.7 million to 9.7 million, representing a growth rate of up to 4.2%. The country's 5th 5-Year Plan (1981-85) has 4 priorities: 1) agricultural modernization, 2) traditional industry and crafts modernization, 3) human resources enhancement, and 4) continued economic growth. Population objectives include 1) increasing peasant aid, 2) making education more development oriented, 3) making health care more accessible, and 4) finding solutions to employment and unemployment problems. The government wants to increase population size because it needs labor for economic development. Programs 1) develop areas with high out-migration, 2) reduce maternal and child mortality, and 3) support family planning only to benefit family well being. Although the Ivory Coast's population will reach 15 million by the year 2000, and population density has tripled since 1950, the country is still thinly populated. The current population policy strives to 1) reduce infant mortality, 2) maintain fertility, and 3) diminish immigration and emigration. Life expectancy is 47 years, infant mortality is 122/1000, and most rural people have no health services. The government considers the total fertility rate of 6.7 satisfactory. Abortion for contraceptive purposes and sterilization are illegal; access to contraception is limited. The Ivory Coast, because of rapid economic growth, attracts immigrants from neighboring countries; at present 1/3 of the population is foreign-born. The government is trying to integrate natives more fully into the labor force. There is little emigration, but internal migration involves almost half of the population. The government attempts to 1) slow down and redirect rural to urban migration to small and medium sized towns and 2) slow rural to rural migration from the savannah to the forest zone. PMID:12314235

  7. Ivory coast microtektites and geomagnetic reversals

    NASA Astrophysics Data System (ADS)

    Schneider, David A.; Kent, Dennis V.

    1990-02-01

    The reported association of the Ivory Coast microtektite occurrence with the onset of the Jaramillo normal polarity subchron has given support to the notion that impact events can give rise to geomagnetic reversals. We re-evaluate the paleomagnetic stratigraphy of two critical deep-sea sediment cores bearing Ivory Coast microtektites (K9-57 and V27-239) and show that this event likely occurred during the Jaramillo subchron approximately 30 kY after its onset and 40 kY before its termination. This new result thus argues against any causal relationship between the Ivory Coast tektite-producing event and a geomagnetic polarity reversal.

  8. Single crystal U-Pb zircon age and Sr-Nd isotopic composition of impactites from the Bosumtwi impact structure, Ghana: Comparison with country rocks and Ivory Coast tektites.

    PubMed

    Ferrière, Ludovic; Koeberl, Christian; Thöni, Martin; Liang, Chen

    2010-08-01

    The 1.07 Myr old Bosumtwi impact structure (Ghana), excavated in 2.1-2.2 Gyr old supracrustal rocks of the Birimian Supergroup, was drilled in 2004. Here, we present single crystal U-Pb zircon ages from a suevite and two meta-graywacke samples recovered from the central uplift (drill core LB-08A), which yield an upper Concordia intercept age of ca. 2145 ± 82 Ma, in very good agreement with previous geochronological data for the West African Craton rocks in Ghana. Whole rock Rb-Sr and Sm-Nd isotope data of six suevites (five from inside the crater and one from outside the northern crater rim), three meta-graywacke, and two phyllite samples from core LB-08A are also presented, providing further insights into the timing of the metamorphism and a possibly related isotopic redistribution of the Bosumtwi crater rocks. Our Rb-Sr and Sm-Nd data show also that the suevites are mixtures of meta-greywacke and phyllite (and possibly a very low amount of granite). A comparison of our new isotopic data with literature data for the Ivory Coast tektites allows to better constrain the parent material of the Ivory Coast tektites (i.e., distal impactites), which is thought to consist of a mixture of metasedimentary rocks (and possibly granite), but with a higher proportion of phyllite (and shale) than the suevites (i.e., proximal impactites). When plotted in a Rb/Sr isochron diagram, the sample data points (n = 29, including literature data) scatter along a regression line, whose slope corresponds to an age of 1846 ± 160 Ma, with an initial Sr isotope ratio of 0.703 ± 0.002. However, due to the extensive alteration of some of the investigated samples and the lithological diversity of the source material, this age, which is in close agreement with a possible "metamorphic age" of ∼ 1.8-1.9 Ga tentatively derived from our U-Pb dating of zircons, is difficult to consider as a reliable metamorphic age. It may perhaps reflect a common ancient source whose Rb-Sr isotope systematics has not basically been reset on the whole rock scale during the Bosumtwi impact event, or even reflect another unknown geologic event. PMID:21037794

  9. Single crystal UPb zircon age and SrNd isotopic composition of impactites from the Bosumtwi impact structure, Ghana: Comparison with country rocks and Ivory Coast tektites

    PubMed Central

    Ferrire, Ludovic; Koeberl, Christian; Thni, Martin; Liang, Chen

    2010-01-01

    The 1.07Myr old Bosumtwi impact structure (Ghana), excavated in 2.12.2Gyr old supracrustal rocks of the Birimian Supergroup, was drilled in 2004. Here, we present single crystal UPb zircon ages from a suevite and two meta-graywacke samples recovered from the central uplift (drill core LB-08A), which yield an upper Concordia intercept age of ca. 214582Ma, in very good agreement with previous geochronological data for the West African Craton rocks in Ghana. Whole rock RbSr and SmNd isotope data of six suevites (five from inside the crater and one from outside the northern crater rim), three meta-graywacke, and two phyllite samples from core LB-08A are also presented, providing further insights into the timing of the metamorphism and a possibly related isotopic redistribution of the Bosumtwi crater rocks. Our RbSr and SmNd data show also that the suevites are mixtures of meta-greywacke and phyllite (and possibly a very low amount of granite). A comparison of our new isotopic data with literature data for the Ivory Coast tektites allows to better constrain the parent material of the Ivory Coast tektites (i.e., distal impactites), which is thought to consist of a mixture of metasedimentary rocks (and possibly granite), but with a higher proportion of phyllite (and shale) than the suevites (i.e., proximal impactites). When plotted in a Rb/Sr isochron diagram, the sample data points (n=29, including literature data) scatter along a regression line, whose slope corresponds to an age of 1846160Ma, with an initial Sr isotope ratio of 0.7030.002. However, due to the extensive alteration of some of the investigated samples and the lithological diversity of the source material, this age, which is in close agreement with a possible metamorphic age of ?1.81.9Ga tentatively derived from our UPb dating of zircons, is difficult to consider as a reliable metamorphic age. It may perhaps reflect a common ancient source whose RbSr isotope systematics has not basically been reset on the whole rock scale during the Bosumtwi impact event, or even reflect another unknown geologic event. PMID:21037794

  10. Tektites and their origin

    NASA Technical Reports Server (NTRS)

    Okeefe, J. A.

    1976-01-01

    Questions concerning the tektite distribution are examined, taking into account the Australasian strewn field, the Ivory Coast strewn field, the Moldavite strewn field, the North American strewn field, the Libyan desert glass, the Aouelloul crater glass, and amerikanites. Attention is given to the shapes of tektites, the internal structure of tektites, the physical properties of tektite glass, the chemical composition of tektites, isotopes, fission tracks, cosmic ray tracks, and arguments in favor and against the terrestrial origin of tektites. It is concluded that tektites cannot be terrestrial in origin. They are probably volcanic ejects, of geologically recent epochs, from one or a number of lunar volcanoes.

  11. Glassy Objects (Microtektites?) from Deep-Sea Sediments near the Ivory Coast.

    PubMed

    Glass, B P

    1968-08-30

    Glassy objects of spherical, oval, dumbbell, teardrop, and irregular shapes have been found in a deep-sea sediment core taken off the Ivory Coast. They occur in a layer of sediment that was apparently deposited about 800,000 years ago. Their geographic location, appearance, and physical properties suggest that they are microtektites and that they are related to the tektite-strewn field of the Ivory Coast. PMID:17812117

  12. North-American Microtektites are More Oxidised than Tektites

    NASA Astrophysics Data System (ADS)

    Giuli, G.; Cicconi, M. R.; Eeckhout, S. G.; Koeberl, C.; Glass, B. P.; Pratesi, G.; Paris, E.

    2012-09-01

    North American (NA) microtektites display Fe3+/Fetot ratios from 0 to 0.75, much higher than microtektites from Ivory Coast and Australasian strewn fields. FTIR determined water content compare well with NA tektites, suggesting lack of alteration.

  13. Phillips goes subsea trees in Ivory Coast

    SciTech Connect

    Bryngelson, R.H.

    1982-11-15

    Describes installation of 3 wet, diver-assist trees, in the Espoir field offshore Ivory Coast, as part of Phillips Petroleum's plans to use 5 satellite wells with downhole completion equipment and subsea production trees. Simplicity in design and attention to training has resulted in an installation time of about 3 weeks for one of the largest subsea trees in the industry. Presents diagram showing the converted jackup, Dan Duke drilling unit, which supports equipment to handle production from subsea wells.

  14. [The migration policy of the Ivory Coast].

    PubMed

    Brou, K; Charbit, Y

    1994-01-01

    Migration policies adopted by the Ivory Coast at independence were essentially a continuation of colonial policies aimed at providing manpower for the coffee and cacao plantations of the south, whose exports were to form the basis of the national development strategy. Instead of forced labor, the government facilitated installation of migrants in agricultural areas by means of laws assuring their access to lands not currently in use. Massive immigration of workers resulted in an age and sex distribution favorable to the needs of the plantation economy. The concentration of development efforts in the forest zone of the south, including Abidjan, encouraged thousands of workers from the savannah to migrate south in search of higher incomes and better living conditions. Bilateral accords with the former Upper Volta and with France and multilateral accords with the Economic Community of the West African states regulated the migratory movement. The Ivory Coast's migration policy succeeded in populating the forest zone and permitted the Ivory Coast to construct a powerful economy. But the policy produced sometimes violent opposition among natives overwhelmed by foreigners in search of lands. The loss of labor force in the savannah threatened the nation's food supply and demographic balance. In the forest zone itself, many of the immigrant workers left the plantations to seek greater success in the cities, swelling the ranks of the urban unemployed and leaving much of the rural area short of labor. In prosperous times, when prices for southern goods were high, the system worked reasonably well. When economic conditions worsened, the inefficiency of the policy became clear. At those times the international conventions failed to control the influx because of the conflicting interests of the countries. Ethnic and regional tensions mounted, the rural exodus continued despite attempts to encourage regional development, and conflicts over land tenure intensified. PMID:12290034

  15. [Waterworks and public health in Ivory Coast].

    PubMed

    Koffi, J K; Koffi, M K; Danguy, E; Adjorlolo, C A; Guessennd, G

    1986-01-01

    In Ivory Coast, the provision for good drinking water has received priority attention since 1973. The National Water-works Programme which started in 1975, is progressing satisfactorily. All over the country, villages and towns are being equipped with hydraulic machines and other structures for the production and distribution of good drinking water. This has contributed in no small way to the control of certain diseases related to water pollution. The authors think however that a lot still needs to be done especially to inform and to educate the village communities and to control the quality of the drinking water. These actions should check water pollution and encourage people in the rural areas to drink portable pipe-borne water. PMID:3014261

  16. Infrasound from lightning measured in Ivory Coast

    NASA Astrophysics Data System (ADS)

    Farges, T.; Matoza, R. S.

    2011-12-01

    It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 lightning flashes are produced per second over the globe. More than two thirds (42) of the infrasound stations of the International Monitoring System (IMS) of the CTBTO (Comprehensive nuclear Test Ban Treaty Organisation) are now certified and routinely measure signals due to natural activity (e.g., airflow over mountains, aurora, microbaroms, surf, volcanoes, severe weather including lightning flashes, ...). Some of the IMS stations are located where worldwide lightning detection networks (e.g. WWLLN) have a weak detection capability but lightning activity is high (e.g. Africa, South America). These infrasound stations are well localised to study lightning flash activity and its disparity, which is a good proxy for global warming. Progress in infrasound array data processing over the past ten years makes such lightning studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure lightning infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from lightning can be detected when the thunderstorm is within about 75 km from the station. The motion of the squall zone is very well measured inside this zone. Up to 25% of lightning flashes can be detected with this technique, giving better results locally than worldwide lightning detection networks. An IMS infrasound station has been installed in Ivory Coast for 8 years. The optical space-based instrument OTD measured a rate of 10-20 flashes/km^2/year in that country and showed strong seasonal variations (Christian et al., 2003). Ivory Coast is therefore a good place to study infrasound data associated with lightning activity and its temporal variation. First statistical results will be presented in this paper based on 3 years of data (2005-2008).

  17. Onchocerciasis in expatriates on the Ivory Coast.

    PubMed

    Mahoney, J L

    1981-03-01

    Six cases of onchocerciasis were diagnosed in expatriates working on a hydroelectric dam project in Taabo (Ivory Coast) between 1977 and 1978. Taabo is in the forest area of the Bandama River, where onchocerciasis is hyperendemic. The six patients had lived in the area from 20 months to four years. In the early 1970s four of them had worked at the Kossou Dam, a similar project 125 miles up the Bandama River. Diagnoses were confirmed by demonstrating microfilariae in biopsy specimens taken from the skin overlying the iliac crest. A seventh case was diagnosed clinically as tropical filarial pulmonary eosinophilia. The six patients with microfilariae in the skin were treated successfully with diethylcarbamazine (Notezine, Hetrazan) and suramin (Moranyl). The patient with pulmonary involvement responded dramatically to treatment with diethylcarbamazine. The overall effects of onchocerciasis are poorly understood, though it is now one of the major tropical diseases, affecting millions of people living in central and western Africa, Yemen, and Central America. Medical treatment is successful, but few preventive measures are available for the disease; larvicides are subject to resistance, and their effects are transient. PMID:6261401

  18. The oldest rock of Ivory Coast

    NASA Astrophysics Data System (ADS)

    Kouamelan, Alain Nicaise; Djro, Sagbrou Chrubin; Allialy, Marc Ephrem; Paquette, Jean-Louis; Peucat, Jean-Jacques

    2015-03-01

    The tonalitic gneiss of Balmer (TGB), in the SASCA area of south-western Ivory Coast, previously dated at 3141 2 Ma using the single zircon evaporation method, is regarded as a relic of Archean rock within the Paleoproterozoic (Birimian) formation of the West African Craton (WAC). We present new geochronological data for the TGB using the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method. We obtain a U-Pb age of 3207 7 Ma for abundant zircons extracted from the tonalitic gneiss, and interpret this age as that of the magmatic protolith because of the igneous-type homogeneous zircon population. Certain magmatic zircon edges and some round zircons define an upper intercept age of 3155 17 Ma which could represent overgrowths during gneissification. It appears that the TGB was not affected by the events posterior to its genesis, i.e. the Liberian (2.9-2.7 Ga) and Eburnean (2.4-2.0 Ga) events. Additionally, the TGB proves to be a juvenile Leonian rock, as indicated by the Nd model age of 3456 Ma, and could also constitute the protolith of the granulitic grey gneisses and charnockites of the Man area, which are 150-400 Ma younger.

  19. Phillips goes subsea trees in Ivory Coast

    SciTech Connect

    Bryngelson, R.H.

    1982-11-15

    Describes installation of 3 satellite subsea trees in 500 ft of water from a semisubmersible drilling rig. These wet, diver-assist trees are part of Phillips Petroleum's early development and production program (EDPP) for the Espoir field offshore Ivory Coast, with plans calling for 5 satellite wells with downhole completion equipment and subsea production trees. Diagram shows how a converted jackup, Dan Duke, supports equipment to handle production from subsea wells. Table gives time breakdown of subsea tree installation. Before mobilizing the subsea trees, control system, and tubulars to the rig, a study of deck layout, payloads, and traffic patterns was performed. Concludes that, based on experience in this project and the cost differences between purchase and installation costs, final success is 90% dependent on informed and trained field personnel after engineering, design, and manufacturing; attention to installation procedures and training of field and operational personnel are as critical or more critical than design changes to equipment; and selection of a supplier for high technology equipment, based on a low bid alone, may not translate into lower installation costs.

  20. Infrasound from lightning measured in Ivory Coast

    NASA Astrophysics Data System (ADS)

    Farges, T.; Millet, C.; Matoza, R. S.

    2012-04-01

    It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 lightning flashes are produced per second over the globe. More than two thirds (42) of the infrasound stations of the International Monitoring System (IMS) of the CTBTO (Comprehensive nuclear Test Ban Treaty Organisation) are now certified and routinely measure signals due to natural activity (e.g., airflow over mountains, aurora, microbaroms, surf, volcanoes, severe weather including lightning flashes, ). Some of the IMS stations are located where worldwide lightning detection networks (e.g. WWLLN) have a weak detection capability but lightning activity is high (e.g. Africa, South America). These infrasound stations are well localised to study lightning flash activity and its disparity, which is a good proxy for global warming. Progress in infrasound array data processing over the past ten years makes such lightning studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure lightning infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from lightning can be detected when the thunderstorm is within about 75 km from the station. The motion of the squall zone is very well measured inside this zone. Up to 25% of lightning flashes can be detected with this technique, giving better results locally than worldwide lightning detection networks. An IMS infrasound station has been installed in Ivory Coast for 9 years. The lightning rate of this region is 10-20 flashes/km2/year from space-based instrument OTD (Christian et al., 2003). Ivory Coast is therefore a good place to study infrasound data associated with lightning activity and its temporal variation. First statistical results will be presented in this paper based on 4 years of data (2005-2009). For short lightning distances (less than 20 km), up to 60 % of lightning detected by WWLLN has been one-to-one correlated. Moreover, numerous infrasound events which have the infrasound from lightning signature could not be correlated when thunderstorms were close to the station. Statistical analyses of all correlated infrasound events show an exponential decrease of the infrasound amplitude with the distance of one order of magnitude per 50 km. These analyses show also that the relative position of lightning is important: the detection limit is higher when lightning occur at the East of the station than when they occur at the West. The dominant wind (the Easterlies) could be responsible of this dissymmetry. It also exists a high variability of detection efficiency with the seasons (better efficiency in fall than in spring). Finally, these statistics show clearly a structure inside the shadow zone (from 70 to 200 km away from the station). These results will be compared with intensive numerical simulations. The simulations are separated into two parts: the simulation of the near-field blast wave generated by a lightning and the simulation of the non-linear propagation of the shock front through a realistic atmosphere. By comparing our numerical results to recorded data over a full 1-year period, we aim to show that dominant features of statistics at the IMS station may be explained by the meteorological variability.

  1. Nd and Sr isotopic evidence for the origin of tektite material from DSDP site 612 off the New Jersey coast

    NASA Technical Reports Server (NTRS)

    Stecher, O.; Ngo, H. H.; Papanastassiou, D. A.; Wasserburg, G. J.

    1989-01-01

    The Sr and Nd isotopic composition was analyzed for samples from the Late Eocene tektite material from DSDP site 612 off the New Jersey coast, to determine whether these tektites may be assigned to the North-American-tektite group. It was found that the ranges of the Sr-87/Sr-86 and the Nd-143/Nd-144 ratios were much wider than in the 612-tectite material than in the tightly constrained group of North American tektites and microtektites and were significantly different from ratios in other groups of tektites. Results indicate that the DSDP tektites were formed from a chemically and isotopically heterogeneous material, in a regime that was different from that of other groups of tektites. It is suggested that the 612-tectites and the North American tektites were either formed by impacts of several bolides in the same general area or by a single impact event that sampled different layers.

  2. Secondary School Alternatives in the Ivory Coast: Considerations.

    ERIC Educational Resources Information Center

    McAnany, Emile G.

    Intended to provide information for Ivorian decision makers, this paper presents an overview of technological alternatives for the delivery of instruction at the post-primary level and their accompanying costs. Five alternatives for regular secondary education as it now exists in the Ivory Coast are reviewed: traditional, audiovisual-traditional,

  3. What it is like to live in the Ivory Coast

    SciTech Connect

    Liddell, W.W.

    1981-09-01

    Exploration and production activity is increasing in the Ivory Coast on the strength of a small discovery by Exxon in 1977 and unofficial reports that Phillips has found a field in deep water which approaches Prudhoe Bay in size. Phillips is bringing five offshore rigs into Ivoirian waters.

  4. North-American Microtektites are More Oxidised than Tektites

    NASA Astrophysics Data System (ADS)

    Giuli, G.; Cicconi, M. R.; Eeckhout, S. G.; Koeberl, C.; Glass, B. P.; Pratesi, G.; Paris, E.

    2012-03-01

    Microtektites from the Australasian and Ivory Coast strewn fields (SF) show low values of the Fe^3^+/Fe_t_o_t ratio, comparable to tektites from the same SF. In contrast, microtektites from the North American SF show a wider range (from 0 to 0.75).

  5. Isotopic fractionation of zinc in tektites

    NASA Astrophysics Data System (ADS)

    Moynier, Frederic; Beck, Pierre; Jourdan, Fred; Yin, Qing-Zhu; Reimold, Uwe; Koeberl, Christian

    2009-01-01

    Tektites are terrestrial natural glasses produced during a hypervelocity impact of an extraterrestrial projectile onto the Earth's surface. The similarity between the chemical and isotopic compositions of tektites and terrestrial upper continental crust implies that the tektites formed by fusion of such target rock. Tektites are among the driest rocks on Earth. Although volatilization at high temperature may have caused this extreme dryness, the exact mechanism of the water loss and the behavior of other volatile species during tektite formation are still debated. Volatilization can fractionate isotopes, therefore, comparing the isotope composition of volatile elements in tektites with that of their source rocks may help to understand the physical conditions during tektite formation. For this study, we have measured the Zn isotopic composition of 20 tektites from four different strewn fields. Almost all samples are enriched in heavy isotopes of Zn compared to the upper continental crust. On average, the different groups of tektites are isotopically distinct (listed from the isotopically lightest to the heaviest): Muong-Nong type indochinites ( ?66/64Zn = 0.61 0.30); North American bediasites ( ?66/64Zn = 1.61 0.49); Ivory Coast tektites ( ?66/64Zn = 1.66 0.18); the Australasian tektites (others than the Muong Nong-type indochinites) ( ?66/64Zn = 1.84 0.42); and Central European moldavites ( ?66/64Zn = 2.04 0.19). These results are contrasted with a narrow range of ?66/64Zn = 0-0.7 for a diverse spectrum of upper continental crust materials. The elemental abundance of Zn is negatively correlated with ?66/64Zn, which may reflect that isotopic fractionation occurred by evaporation during the heating event upon tektite formation. Simple Rayleigh distillation predicts isotopic fractionations much larger than what is actually observed, therefore, such a model cannot account for the observed Zn isotope fractionation in tektites. We have developed a more realistic model of evaporation of Zn from a molten sphere: during its hypervelocity trajectory, the molten surface of the tektite will be entrained by viscous coupling with air that will then induce a velocity field inside the molten sphere. This velocity field induces significant radial chemical mixing within the tektite that accelerates the evaporation process. Our model, albeit parameter dependent, shows that both the isotopic composition and the chemical abundances measured in tektites can be produced by evaporation in a diffusion-limited regime.

  6. The Influence of Predisposing, Enabling and Need Factors on Condom Use in Ivory Coast

    ERIC Educational Resources Information Center

    Ngamini Ngui, Andre

    2010-01-01

    The main objective of this study was to identify key determinants of condom use in Ivory Coast. Data stem from Ivory Coast Demographic Health Survey (DHS) conducted by ORC Macro in 2005 among a representative sample of 9,686 persons aged 15 - 49. Following the behavioral model, we use logistic regression to assess the effect of predisposing,…

  7. Detection of Mycobacterium ulcerans DNA in the Environment, Ivory Coast

    PubMed Central

    Tian, Roger Bi Diangoné; Niamké, Sébastian; Tissot-Dupont, Hervé; Drancourt, Michel

    2016-01-01

    Background Ivory Coast is a West African country with the highest reported cases of Buruli ulcer, a disabling subcutaneous infection due to Mycobacterium ulcerans. However, the prevalence of environmental M. ulcerans is poorly known in this country. Methods We collected 496 environmental specimens consisting of soil (n = 100), stagnant water (n = 200), plants (n = 100) and animal feces (n = 96) in Ivory Coast over five months in the dry and wet seasons in regions which are free of Buruli ulcer (control group A; 250 specimens) and in regions where the Buruli ulcer is endemic (group B; 246 specimens). After appropriate total DNA extraction incorporating an internal control, the M. ulcerans IS2404 and KR-B gene were amplified by real-time PCR in samples. In parallel, a calibration curve was done for M. ulcerans Agy99 IS2404 and KR-B gene. Results Of 460 samples free of PCR inhibition, a positive real-time PCR detection of insertion sequence IS2404 and KR-B gene was observed in 1/230 specimens in control group A versus 9/230 specimens in group B (P = 0.02; Fisher exact test). Positive specimens comprised seven stagnant water specimens, two feces specimens confirmed to be of Thryonomys swinderianus (agouti) origin by real-time PCR of the cytb gene; and one soil specimen. Extrapolation from the calibration curves indicated low inoculums ranging from 1 to 102 mycobacteria/mL. Conclusion This study confirms the presence of M. ulcerans in the watery environment surrounding patients with Buruli ulcer in Ivory Coast. It suggests that the agouti, which is in close contacts with populations, could play a role in the environmental cycle of M. ulcerans, as previously suggested for the closely related possums in Australia. PMID:26982581

  8. [Toxic waste and health effects in Abidjan City, Ivory Coast].

    PubMed

    Bohand, X; Monpeurt, C; Bohand, S; Cazoulat, A

    2007-12-01

    Accidental chemical pollution can have serious effects on human health. In 2006, the tanker vessel Probo Koala discharged hundreds of tons of toxic waste at many sites in Abidjan City, Ivory Coast. In the following days and weeks, thousands of people presented signs of poisoning. Analysis of the waste demonstrated the presence of toxic chemicals such as mercaptans and hydrogen sulfide. The final toll was 8 dead, dozens hospitalized, and about 100,000 seeking medical advice. This event provides evidence that, like international immigration, exportation of industrial waste can result in serious public health hazards. PMID:18300527

  9. Tektite origin by hypervelocity asteroidal or cometary impact: The quest for the source craters

    NASA Technical Reports Server (NTRS)

    Koeberl, Christian

    1992-01-01

    Tektites are natural glasses that are chemically homogeneous, often spherically symmetrical objects several centimeters in size, and occur in four known strewn fields on the surface of the Earth: the North American, moldavite (or Central European), Ivory Coast, and Australasian strewn fields. Tektites found within such strewn fields are related to each other with respect to their petrological, physical, and chemical properties as well as their age. A theory of tektite origin needs to explain the similarity of tektites in respect to age and certain aspects of isotopic and chemical composition within one strewn field, as well as the variety of tektite materials present in each strewn field. In addition to tektites on land, microtektites (which are generally less than 1 mm in diameter) have been found in deep-sea cores. Tektites are classified into three groups: (1) normal or splash-form tektites, (2) aerodynamically shaped tektites, and (3) Muong Nong-type tektites (sometimes also called layered tektites). The aerodynamic ablation results from partial remelting of glass during atmospheric passage after it was ejected outside the terrestrial atmosphere and quenched from a hot liquid. Aerodynamically shaped tektites are known mainly from the Australasian strewn field where they occur as flanged-button australites. The shapes of splash-form tektites (spheres, droplets, teardrops, dumbbells, etc., or fragments thereof) are the result of the solidification of rotating liquids in the air or vacuum. Mainly due to chemical studies, it is now commonly accepted that tektites are the product of melting and quenching of terrestrial rocks during hypervelocity impact on the Earth. The chemistry of tektites is in many respects identical to the composition of upper crustal material.

  10. Nd and Sr isotopic compositions of tektite material from Barbados and their relationship to North American tektites

    NASA Technical Reports Server (NTRS)

    Ngo, H. H.; Wasserburg, J.; Glass, B. P.

    1985-01-01

    The isotopic composition of microtektites from Barbados was determined to establish their possible source and their relationship to known tektite strewn fields. Analyzed samples included microtektites and tektite fragments from the Barbados oceanic beds, samples of deep sea ooze, in which they occur, and of underlying volcanic ash, as well as glass beads from Lake Wanapitei Crater. Isotope ratios (Sr-87/Sr-86, Nd-143/Nd-144, Rb-87/Sr-86, and Sm-147/Nd-144) were determined, and the epsilon values for Sr and Nd plotted on the diagram available for the fields of North America, Australia, Ivory Coast, and Moldavite tektites. The epsilon coordinates of all Barbados microtektite and bulk tektite samples plot precisely within the narrow field determined by North American tektites (epsilon Sr, 111; epsilon Nd, -6.2), yield an Nd model age of 0.6 AE, and are distinct from all other fields. The isotopic signatures of samples from sea ooze, ash layer, and of the Lake Wanapitei glass beads are clearly different from all known tektite classes. It is concluded that the Barbados tektites are of the same source and temporal event as the North American tektites.

  11. Innovative production system goes in off Ivory Coast

    SciTech Connect

    Childers, M.; Barnes, J. |

    1995-07-17

    The phased field development of the Lion and Panthere fields, offshore the Ivory Coast, includes a small floating production, storage, and offloading (FPSO) tanker with minimal processing capability as an early oil production system (EPS). For the long-term production scheme, the FPSO will be replaced by a converted jack up mobile offshore production system (MOPS) with full process equipment. The development also includes guyed-caisson well platforms, pipeline export for natural gas to fuel an onshore power plant, and a floating storage and offloading (FSO) tanker for oil export. Pipeline export for oil is a future possibility. This array of innovative strategies and techniques seldom has been brought together in a single project. The paper describes the development plan, early oil, jack up MOPS, and transport and installation.

  12. [Traditional health practitioners and epilepsies in Ivory Coast].

    PubMed

    François, A A; Elisée, B K; Christian, T A; Armel, K H; Any, G; Tchwa, A M; Constance, Y A

    2014-01-01

    We report the results of a descriptive 3-month observational study concerning the experience and knowledge about epilepsy of 30 traditional health practitioners in the Ivory Coast. Most respondents were men over 30 years of age. They had an average of 14.3 years of professional experience. More than half of respondents (54%) had not attended school. All traditional practitioners knew that epilepsy was a brain disease. For 83.3% of them, the disease was supernatural, due to a curse. These traditional healers knew all the clinical manifestations of generalized tonico-clonic seizure. For over 72% of them, noise, presence of a public, nervousness and coffee consumption were factors favoring seizures. Sixty percent of the traditional healers still believed in the contagiousness of epilepsy, and all claimed to cure it by traditional treatment. Most all healers (97%) used plant products, but only 10% released the name of the plants used (Rubiaceae or Lamiaceae families). This survey highlights the urgency of awareness campaigns and the need for training of Ivorian traditional healers and the necessity to improve the collaboration between modern and traditional medicine. PMID:25193012

  13. Energy assessment of Ivory Coast, Morocco, Nigeria, and Senegal

    SciTech Connect

    Ghirardi, A.; Sathaye, J.; Goering, P.

    1986-11-01

    This report is an overview of the energy market in four West African countries: The Ivory Coast, Morocco, Nigeria, and Senegal. We feel these countries are representative of the West African region. Together they account for 75% of the total energy use in West Africa, 78% of GDP, and 76% of population. The purpose of the study is to analyze the evolution of energy demand in the context of the general socio-economic background of the region. The study also examines energy supply and trade related to the energy sector. The analysis focuses on the study of commercial fuels. Although we have reviewed studies of wood, solar, wind, and agricultural residues, we leave out detailed discussions of these non-commercial energy forms. The first part of the report is an assessment of the trends in energy demand in the four study countries. We discuss the main factors driving energy demand sector by sector. This is followed by a review of the primary energy resources of the countries, and of the capacity for production of secondary fuels. The last section looks at energy trade, with particular emphasis on the role of the United States.

  14. Ivory Coast-Ghana margin: model of a transform margin

    SciTech Connect

    Mascle, J.; Blarez, E.

    1987-05-01

    The authors present a marine study of the eastern Ivory Coast-Ghana continental margins which they consider one of the most spectacular extinct transform margins. This margin has been created during Early-Lower Cretaceous time and has not been submitted to any major geodynamic reactivation since its fabric. Based on this example, they propose to consider during the evolution of the transform margin four main and successive stages. Shearing contact is first active between two probably thick continental crusts and then between progressively thinning continental crusts. This leads to the creation of specific geological structures such as pull-apart graben, elongated fault lineaments, major fault scarps, shear folds, and marginal ridges. After the final continental breakup, a hot center (the mid-oceanic ridge axis) is progressively drifting along the newly created margin. The contact between two lithospheres of different nature should necessarily induce, by thermal exchanges, vertical crustal readjustments. Finally, the transform margin remains directly adjacent to a hot but cooling oceanic lithosphere; its subsidence behavior should then progressively be comparable to the thermal subsidence of classic rifted margins.

  15. On the occurrence of gold mineralizations in southeastern Ivory Coast

    NASA Astrophysics Data System (ADS)

    Kadio, E.; Coulibaly, Y.; Allialy, M. E.; Kouamelan, A. N.; Pothin, K. B. K.

    2010-07-01

    Gold mineralizations are known to occur in the Paleoproterozoic (Birimian) formations of the Aboisso area, southeastern Ivory Coast. These formations, which have been structured during the Eburnean orogeny, mainly consist of volcanic, volcaniclastic and sedimentary rocks intruded by granitic, basic and ultrabasic plutons. Exploration of these terranes has revealed numerous gold mineralizations, the most significant of which are located in the Afma shear zone. Four distinct types of mineralizations can be distinguished based on the typology of the host rocks. These include mineralizations enclosed in highly silicified volcanic rocks (type 1), mineralizations closely related to intense silicification of metasedimentary rocks (type 2), mineralizations associated with silicified polygenic conglomerates (type 3), and mineralizations encountered in brecciated and silicified zones within a metadiorite sill (type 4). Gold is observed either as free gold, or in association with pyrite, arsenopyrite, sphalerite, chalcopyrite, pyrrhotite, galena, anatase, monazite, magnetite. Gold and the various sulfides are mostly of hydrothermal epigenetic origin. The fact that the gold mineralizations occurs in brecciated and silicified zones around granitoid intrusions clearly indicates that post-magmatic hydrothermal activity and tectonics exerted a major control during the mineralization process.

  16. Zhamanshin and Aouelloul - Craters produced by impact of tektite-like glasses?

    NASA Technical Reports Server (NTRS)

    O'Keefe, John A.

    1987-01-01

    It is shown that the enhanced abundance of siderophile elements and chromium in tektite-like glasses from the two impact craters of Zhamanshin and Aouelloul cannot be explained as a result of contamination of the country rock by meteorites nor, probably, comets. The pattern is, however, like that found in certain Australasian tektites, and in Ivory Coast tektites. It is concluded, in agreement with earlier suggestions by Campbell-Smith and Hey, that these craters were formed by the impact of large masses of tektite-like glass, of which the glasses which were studied are fragments. It follows that it is necessary, in considering an impact crater, to bear in mind that the projectile may have been a glass.

  17. Zhamanshin and Aouelloul - Craters produced by impact of tektite-like glasses?

    NASA Astrophysics Data System (ADS)

    O'Keefe, John A.

    1987-09-01

    It is shown that the enhanced abundance of siderophile elements and chromium in tektite-like glasses from the two impact craters of Zhamanshin and Aouelloul cannot be explained as a result of contamination of the country rock by meteorites nor, probably, comets. The pattern is, however, like that found in certain Australasian tektites, and in Ivory Coast tektites. It is concluded, in agreement with earlier suggestions by Campbell-Smith and Hey, that these craters were formed by the impact of large masses of tektite-like glass, of which the glasses which were studied are fragments. It follows that it is necessary, in considering an impact crater, to bear in mind that the projectile may have been a glass.

  18. Fragmentation and hydration of tektites and microtektites

    USGS Publications Warehouse

    Glass, B.P.; Muenow, D.W.; Bohor, B.F.; Meeker, G.P.

    1997-01-01

    An examination of data collected over the last 30 years indicates that the percent of glass fragments vs. whole splash forms in the Cenozoic microtektite strewn fields increases towards the source crater (or source region). We propose that this is due to thermal stress produced when tektites and larger microtektites fall into water near the source crater while still relatively hot (>1150 ??C). We also find evidence (low major oxide totals, frothing when melted) for hydration of most of the North American tektite fragments and microtektites found in marine sediments. High-temperature mass spectrometry indicates that these tektite fragments and microtektites contain up to 3.8 wt% H2O. The H2O-release behavior during the high-temperature mass-spectrometric analysis, plus high Cl abundances (???0.05 wt%), indicate that the North. American tektite fragments and microtektites were hydrated in the marine environment (i.e., the H2O was not trapped solely on quenching from a melt). The younger Ivory Coast and Australasian microtektites do not exhibit much evidence of hydration (at least not in excess of 0.5 wt% H2O); this suggests that the degree of hydration increases with age. In addition, we find that some glass spherules (with 65 wt% SiO2 can undergo simple hydration in the marine environment, while impact glasses (with <65 wt% SiO2) can also undergo palagonitization.

  19. Lassa virus isolates from Mali and the Ivory Coast represent an emerging fifth lineage

    PubMed Central

    Manning, John T.; Forrester, Naomi; Paessler, Slobodan

    2015-01-01

    Previous imported cases of Lassa fever (LF) into the United Kingdom from the Ivory Coast and Mali, as well as the detection of Lassa virus (LASV) among the Mastomys natalensis population within Mali has led to the suggestion that the endemic area for LF is expanding. Initial phylogenetic analyses arrange isolates from Mali and the Ivory Coast separately from the classical lineage IV isolates taken from Sierra Leone, Guinea, and Liberia. The availability of full genome sequences continues to increase, allowing for a more complete phylogenetic comparison of the isolates from Mali and the Ivory Coast to the other existing isolates. In this study, we utilized a Bayesian approach to infer the demographic histories of each LASV isolate for which the full sequence was available. Our results indicate that the isolates from Mali and the Ivory Coast group separately from the isolates of lineage IV, comprising a distinct fifth lineage. The split between lineages IV and V is estimated to have occurred around 200–300 years ago, which coincides with the colonial period of West Africa. PMID:26483768

  20. Lassa virus isolates from Mali and the Ivory Coast represent an emerging fifth lineage.

    PubMed

    Manning, John T; Forrester, Naomi; Paessler, Slobodan

    2015-01-01

    Previous imported cases of Lassa fever (LF) into the United Kingdom from the Ivory Coast and Mali, as well as the detection of Lassa virus (LASV) among the Mastomys natalensis population within Mali has led to the suggestion that the endemic area for LF is expanding. Initial phylogenetic analyses arrange isolates from Mali and the Ivory Coast separately from the classical lineage IV isolates taken from Sierra Leone, Guinea, and Liberia. The availability of full genome sequences continues to increase, allowing for a more complete phylogenetic comparison of the isolates from Mali and the Ivory Coast to the other existing isolates. In this study, we utilized a Bayesian approach to infer the demographic histories of each LASV isolate for which the full sequence was available. Our results indicate that the isolates from Mali and the Ivory Coast group separately from the isolates of lineage IV, comprising a distinct fifth lineage. The split between lineages IV and V is estimated to have occurred around 200-300 years ago, which coincides with the colonial period of West Africa. PMID:26483768

  1. [History of an epidemiological route between Ivory Coast and Burkina Faso: the case of the Koudougou sleeping sickness foci].

    PubMed

    Kiendrbogo, D; Kambir, R; Jamonneau, V; Lingu, K; Solano, P; Courtin, F

    2012-11-01

    In the first half of the XXth century, while Upper-Volta (now Burkina Faso) was suffering a terrible epidemic of sleeping sickness, the French colonial administration encouraged the movement of people from Upper-Volta to Ivory Coast to meet their demands for labour. This led to the establishment of Mossi villages, such as those of Koudougou, in the Ivorian forest with populations originating from areas of Upper-Volta that were not only densely populated but also severely affected by sleeping sickness. Since 2000, most cases of sleeping sickness in the Koudougou district of Burkina Faso have been in people originally from Ivory Coast. Who are they? Where did they settle in Burkina Faso? Where do they come from in Ivory Coast? After having retraced the epidemiological history of Koudougou villages in Burkina Faso and Ivory Coast, the history of ten cases of sleeping sickness detected passively at Koudougou hospital since 2000 were analysed. All cases originated from the forest area of Ivory Coast. Understanding the spread of sleeping sickness between Burkina Faso and Ivory Coast will assist in the identification of areas of disease risk. PMID:23193525

  2. Genetic population study of Y-chromosome markers in Benin and Ivory Coast ethnic groups.

    PubMed

    Fortes-Lima, Cesar; Brucato, Nicolas; Croze, Myriam; Bellis, Gil; Schiavinato, Stephanie; Massougbodji, Achille; Migot-Nabias, Florence; Dugoujon, Jean-Michel

    2015-11-01

    Ninety-six single nucleotide polymorphisms (SNPs) and seventeen short tandem repeat (STRs) were investigated on the Y-chromosome of 288 unrelated healthy individuals from populations in Benin (Bariba, Yoruba, and Fon) and the Ivory Coast (Ahizi and Yacouba). We performed a multidimensional scaling analysis based on FST and RST genetic distances using a large extensive database of sub-Saharan African populations. There is more genetic homogeneity in Ivory Coast populations compared with populations from Benin. Notably, the Beninese Yoruba are significantly differentiated from neighbouring groups, but also from the Yoruba from Nigeria (FST>0.05; P<0.01). The Y-chromosome dataset presented here provides new valuable data to understand the complex genetic diversity and human male demographic events in West Africa. PMID:26275614

  3. [The Senegalese community in the Ivory Coast and national immigration policy redefined].

    PubMed

    Bredeloup, S

    1996-03-01

    "International economic crisis has increased constraints from which Senegalese migrants were already suffering both in their country of origin and in the receiving countries.... Since 1991, the introduction of compulsory residence permits for foreign workers...[bears] witness to the degrading conditions for those entering the Ivory Coast and also reveals that agreements of free movement were in fact not working." (SUMMARY IN ENG) PMID:12320683

  4. Reasons for blood donation deferral in sub-Saharan Africa: experience in Ivory Coast

    PubMed Central

    Kouao, Maxime Diane; Dembel, Bamory; NGoran, Landry Kouassi; Konat, Seidou; Bloch, Evan; Murphy, Edward L.; Lefrre, Jean-Jacques

    2013-01-01

    INTRODUCTION Blood donor selection is important to ensure the safety of both donors and recipients. There is a paucity of data on reasons for blood donor deferral in Ivory Coast. The aim of this study was to identify the reasons for predonation deferral at a blood collection site at General Hospital, Yopougon Atti in Abidjan. MATERIALS AND METHODS The investigators conducted a retrospective audit of data pertaining to donor deferral for blood donors that presented to the general hospital of Yopugon Atti from January 1, 2006 to December 31, 2008. RESULTS A total of 10,694 prospective blood donors, presented over the study period, and 24,363 attempts to donate were registered. The majority were repeat blood donors (77.4%). A total of 2618 (10.8%) donors were deferred. The most frequent reason for deferral was a low hemoglobin level (42.5%), with females constituting the majority of those deferred. The second most frequent reason for deferral was a reported change of or new sexual partner (34.3%); male donors were predominant in this group. Additional reasons for deferral included short interdonation interval (4.6%) and reactivity for a screened biomarker (2.3%). CONCLUSION Although the rates for permanent and temporary deferral rates are similar between the Ivory Coast and high-middle income countries, the causes and demographics differ. The reasons for exclusion are preventable through awareness and education of prospective blood donors. PMID:22780941

  5. ACE and LRPAP1 insertion-deletion polymorphisms in a northern Ivory Coast population.

    PubMed

    Santovito, A; Burgarello, C; Bulgarello, C; Caravatti, G A; Ouattar, M; Cervella, P; Pisano, G; Salvarani, B; Delpero, M

    2007-12-01

    The ACE and the LRPAP1 gene insertion-deletion polymorphisms were determined in 133 healthy individuals sampled from Ouangolodougou, a village located in northern Ivory Coast. No sex differences were found in ACE and LRPAP1 gene frequencies. The ACE insertion and deletion alleles had frequencies of 0.346 and 0.654, respectively. The ACE gene was not in Hardy-Weinberg equilibrium because of an excess of heterozygote genotypes and a deficiency of I/I genotypes compared to the expected values. Statistical analysis showed a significantly lower frequency of I/I genotypes in the Ivory Coast population compared to Sudan, Kenya, African Americans, and African Brazilians (p < 0.05), whereas no differences were found with respect to Somalia. Conversely, the frequencies of the insertion and deletion alleles in the Ivorian population did not differ from those of other African populations. The LRPAP1 insertion and deletion allele frequencies found in our study (0.192 and 0.808, respectively) did not differ significantly from the Czech and Spanish populations, the only two populations previously characterized for this polymorphism. However, the frequency of the I/I genotype was significantly lower than the frequencies observed in the European samples. Because of the limited information on the LRPAP1 gene polymorphism distribution in worldwide populations, it was not possible to draw any conclusion. PMID:18494379

  6. Evolution of a Paleoproterozoic weak type orogeny in the West African Craton (Ivory Coast)

    NASA Astrophysics Data System (ADS)

    Vidal, M.; Gumiaux, C.; Cagnard, F.; Pouclet, A.; Ouattara, G.; Pichon, M.

    2009-11-01

    The Paleoproterozoic domain of the Ivory Coast lies in the central part of the West African Craton (WAC) and is mainly constituted by TTG, greenstones, supracrustal rocks and leucogranites. A compilation of metamorphic and radiometric data highlights that: i) metamorphic conditions are rather homogeneous through the domain, without important metamorphic jumps, ii) HP-LT assemblages are absent and iii) important volumes of magmas emplaced during the overall Paleoproterozoic orogeny suggesting the occurrence of long-lived rather hot geotherms. Results of the structural analysis, focused on three areas within the Ivory Coast, suggest that the deformation is homogeneous and distributed through the Paleoproterozoic domain. In details, results of this study point out the long-lived character of vertical movements during the Eburnean orogeny with a two folds evolution. The first stage is characterized by the development of "domes and basins" geometries without any boundary tectonic forces and the second stage is marked by coeval diapiric movements and horizontal regional-scale shortening. These features suggest that the crust is affected by vertical movements during the overall orogeny. The Eburnean orogen can then be considered as an example of long-lived Paleoproterozoic "weak type" orogen.

  7. [Malaria in military personnel: the case of the Ivory Coast in 2002-2003].

    PubMed

    Migliani, R; Josse, R; Hovette, P; Keundjian, A; Pages, F; Meynard, J-B; Ollivier, L; Sbai Idrissi, K; Tifratene, K; Orlandi, E; Rogier, C; Boutin, J-P

    2003-01-01

    French troops were sent to the Ivory Coast on September 22, 2002 within the framework of Operation Unicorn in response to the political unrest. From September 22 to October 20, a total of 37 cases of malaria were reported, i.e., 35.7 cases per 1000 man-months. As of October 11, the central headquarters of the Armed Services Health Corps decided to use doxycycline as the exclusive agent for drug prophylaxis in military personnel on duty in the Ivory Coast and to enhance vector control measures. The incidence of malaria decreased to 2 cases per 1000 man-months at the sixth month. A recrudescence of malaria to 15 cases per 1000 man-months was observed with the rainy season in April. During this period one person presenting severe malaria with coma required emergency evacuation to France. In May 2003, several studies were undertaken to determine the factors that caused this recrudescence. These studies included surveys to evaluate awareness concerning malaria and monitor compliance with drug prophylaxis and tolerance of doxycycline, a case-control study to identify factors related to malarious episodes and an entomological study. Awareness of malaria was high with 75% of the 477 respondents stating that malaria could be transmitted by single mosquito bite. The case-control study showed a correlation between occurrence of malarious bouts and non-compliance with drug prophylaxis (p < 10(-5)). The odds-ratio was 3.05 (95% confidence interval, 1.52-6.14) for subjects claiming zero to one incident of non-compliance per week and 7.51 (IC95%, 3.24-17.40) for those claiming more than one incident of non-compliance per week. Tolerance of doxycyline was good since 72% of respondents reported no adverse effects. The main vector was Anopheles gambiae. The number of bites per man per night ranged from 25 to 2 and the number of infected bites ranged from 2 to 3 per week. Treatment was initiated promptly using quinine at a total dose of 25 mg/kg in 3 daily doses for 7 days by the intravenous then oral route. This experience shows that malaria remains a major concern for military forces, that standardization of preventive measures in emergency situations is needed, and that enhanced vector control, verification of compliance with drug prophylaxis and prompt treatment based on the presence of a physician in each emergency outpost is crucial. These recommendation must be applied to all French military personnel in the Ivory Coast. PMID:14579467

  8. Sonomorphologic evaluation of goiter in an iodine deficiency area in the Ivory Coast.

    PubMed Central

    Franke, D; Filler, G; Zivicnjak, M; Kouam, P; Ohde, I; Eckhardt, L; Doehring, E; Ehrich, J H

    1999-01-01

    OBJECTIVES: This study evaluated the extent of thyroid abnormalities in a remote iodine-deficient area of the Ivory Coast. METHODS: Ultrasonography was used in detecting the presence of goiter. RESULTS: The overall prevalence rates of goiter were 64.7% among females and 53.3% among males. In children aged 6 to 15 years (n = 314), the prevalence of goiter was 62% regardless of sex. Thyroid volume increased steadily with age, with significantly larger goiters in women 25 years and older. Frequency of cysts and calcifications did not correlate with sex. CONCLUSIONS: Especially in developing countries, prophylaxis of iodine deficiency disorders must be improved in iodine-deficient areas to prevent substantial morbidity, which is more severe in women and elderly persons. PMID:10589317

  9. Allele and haplotype diversity of X-chromosomal STRs in Ivory Coast.

    PubMed

    Pasino, Serena; Caratti, Stefano; Del Pero, Massimiliano; Santovito, Alfredo; Torre, Carlo; Robino, Carlo

    2011-09-01

    Twenty-one X-chromosomal short tandem repeat (STR) loci, including the six clusters of linked markers DXS10148-DXS10135-DXS8378 (Xp22), DXS7132-DXS10079-DXS10074 (Xq12), DXS6801-DXS6809-DXS6789 (Xq21), DXS7424-DXS101 (Xq22), DXS10103-HPRTB-DXS10101 (Xq26), DXS8377-DXS10146-DXS10134-DXS7423 (Xq28) and the loci DXS6800, GATA172D05 and DXS10011 were typed in a population sample from Ivory Coast (n=125; 51 men and 74 women). Allele and haplotype frequencies as well as linkage disequilibrium data for kinship calculations are provided. On the whole, no significant differences in the genetic variability of X-STR markers were observed between Ivorians and other sub-Saharan African populations belonging to the Niger-Kordofanian linguistic group. PMID:21717153

  10. Mineralogical, crystallographic and morphological characteristics of natural kaolins from the Ivory Coast (West Africa)

    NASA Astrophysics Data System (ADS)

    Sei, J.; Morato, F.; Kra, G.; Staunton, S.; Quiquampoix, H.; Jumas, J. C.; Olivier-Fourcade, J.

    2006-10-01

    Thirteen clay samples from four deposits in the Ivory Coast (West Africa) were studied using X-ray diffraction, thermogravimetric analysis and chemical analysis. Mineralogical, crystallographic and morphological characteristics of these samples are given. Kaolinite is the principal mineral but other minerals are present in small quantities: illite, quartz, anatase and iron oxides (oxides and oxyhydroxides). The crystallographic, morphological and surface characteristics are influenced by the presence of these impurities. In particular, the presence of iron oxides was associated with reduced structural ordering and thermal stability of kaolinite and increased specific surface area. These clays could be used in the ceramics industry to make tiles and bricks, and also in agronomy as supports for chemical fertilizers or for environmental protection by immobilising potentially toxic waste products.

  11. [Bone manifestations of multiple myeloma in the Ivory Coast. Apropos of 27 cases].

    PubMed

    Leleu, J P; Toutou, T; Soubeyrand, J; Rain, J D; Beda, Y B

    1983-01-01

    Report on 27 cases of multiple myeloma recorded in 10 years and 24000 in-patients of Treichville University Hospital in Abidjan (Republic of Ivory Coast). The sex-ratio is 70% of males versus 30% of females and the frequency ranges from 25 years to a maximum between 55 and 75 years. First warning symptoms are pains (70%) then fractures (14,1%), biologic disorders (11,1%) and tumors (7,4%). Vertebrae and flat bones are most often affected with a special frequency for skull and jaw. Radiological aspects and biological changes are reviewed; a high blood sedimentation rate, rather common in Africans, has not the same value as in Caucasians. PMID:6310313

  12. Phenetic and genetic structure of tsetse fly populations (Glossina palpalis palpalis) in southern Ivory Coast

    PubMed Central

    2012-01-01

    Background Sleeping sickness, transmitted by G. p. palpalis, is known to be present in the Ivory Coast. G. p. palpalis has recently been reported to occur in several places within the town of Abidjan, including: (i) the Banco forest, (ii) the Abobo Adjam University campus and (iii) the zoological park. Could these three places be treated sequentially, as separate tsetse populations, or should they be taken as one area comprising a single, panmictic population? Methods The amount of gene flow between these places provides strategic information for vector control. It was estimated by the use of both microsatellite DNA and morphometric markers. The idea was to assess the interest of the faster and much less expensive morphometric approach in providing relevant information about population structure. Thus, to detect possible lack of insect exchange between these neighbouring areas of Abidjan, we used both genetic (microsatellite DNA) and phenetic (geometric morphometrics) markers on the same specimens. Using these same markers, we also compared these samples with specimens from a more distant area of south Ivory Coast, the region of Aniassu (186 km north from Abidjan). Results Neither genetic nor phenetic markers detected significant differentiation between the three Abidjan G. p. palpalis samples. Thus, the null hypothesis of a single panmictic population within the city of Abidjan could not be rejected, suggesting the control strategy should not consider them separately. The markers were also in agreement when comparing G. p. palpalis from Abidjan with those of Aniassu, showing significant divergence between the two sites. Conclusions Both markers suggested that a successful control of tsetse in Abidjan would require the three Abidjan sites to be considered together, either by deploying control measures simultaneously in all three sites, or by a continuous progression of interventions following for instance the "rolling carpet" principle. To compare the geometry of wing venation of tsetse flies is a cheap and fast technique. Agreement with the microsatellite approach highlights its potential for rapid assessment of population structure. PMID:22846152

  13. Female genital mutilation and intimate partner violence in the Ivory Coast

    PubMed Central

    2014-01-01

    Background Serious forms of violence against women include Female Genital Mutilation (FGM) and Intimate Partner Violence (IPV). The aim of this study was to determine if FGM is associated with IPV, using data obtained from the Demographic and Health Survey (DHS) 2012 in Ivory Coast. Methods Participants for this study were drawn from the 2011-12 Ivory Coast Demographic and Health Survey (CDHS), a nationally representative sample of 10060 women aged 15 to 49 years. The analysis of this paper is restricted to the sample of women who responded to the FGM and domestic violence modules (N?=?5005). Results The lifetime prevalence of physical violence was 24.8%, sexual violence, 5.7%, and emotional violence, 19.0%, and the prevalence of any lifetime IPV was 32.1%. In all, 40.6% reported female genital cutting or mutilation (FGM). Women reporting FGM were two times as likely to experience sexual IPV (AOR: 1.96, CI: 1.29-2.98), while other subtypes of IPV were higher in women reporting FGM but they were not significant. Of the socio-demographic covariates, urban residence and having a primary education were associated with most subtypes of IPV, while being a Muslim seemed protective from any type, sexual and emotional IPV. Having seen the father beating the mother was positively associated with most IPV subtypes, and having been diagnosed with a sexually transmitted infection (STI) in the previous 12 months was associated with physical and sexual IPV. Conclusion Significant rates of FGM and IPV were found among this sample of Ivorian women calling for the need for multiple strategies to reduce FGM and IPV. PMID:24451017

  14. [Stegomyian indices and epidemiological status of yellow fever in a rural area of the Ivory Coast].

    PubMed

    Zeze, D G; Koffi, A A

    1994-01-01

    The M'bahiakro region, located in the center of Ivory Coast and inhabited by the N'gain, has been the scene of a yellow fever epidemic since 1982. This region reunites all the conditions for cyclic emergence of the flavivirus given the current epidemiologic pattern of yellow fever in Africa. In view of this situation ORSTOM, in collaboration with the Pasteur Institute of Ivory Coast, has created a pilot zone for epidemiologic surveillance of yellow fever in this region. The N'gain region which has a total population of 12,000 living in 20 villages with between 100 and 2000 inhabitants is located in a preforest area with an attenuated transitional climate characterized by a dry season and a rainy season with two peak periods of precipitation (May and October) but a low mean annual rainfall (1172 mm). There are few springs, wells and rivers and maintaining water supplies is difficult. As a result villagers stockpile rainwater in various types of containers. Inspections were carried out from February to July in the 20 villages of the region. Each room of every dwelling was registered and visited. Water reserves were inspected and those containing pre-imaginal stage Culicidae were counted as positive. Nymphs and larva were sometimes collected. Nymphs were raised and larva preserved. Species identification by the laboratory was based on these larva and imagos obtained by raising the nymphs. Correspondence tables established by the World Health Organization between stegomiyan indices (dwelling), container, BRETEAU) and flavivirus in the population were used to exploit the results.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7746124

  15. Origins and dispersal of the mitochondrial DNA region V 9 bp deletion and insertion in Nigeria and the Ivory Coast

    SciTech Connect

    Merriwether, D.A.; Huston, S.L.; Bunker, C.A.

    1994-09-01

    An intergenic region V Mitochondrial DNA (mtDNA) 9 bp deletion located between the genes for tRNA{sup LYS} and cytochrome oxidase II was discovered in a small percentage of Nigerian and Ivory Coast natives. Previously this deletion has been described as Asian-specific and has been reported throughout the New World, Asia, S.E. Asia, and the Pacific Islands at frequencies ranging from 0% to 100%. In the New World and the Pacific Islands, the deletion is almost always accompanied by an Hae III restriction site gain at nt 16517. All 9 occurrences of the deletion observed in Africa (from four different populations) co-occur with the Hae III 16517 site gain, indicating that the African deletion probably shares a common origin with the deletion described as {open_quotes}Asian-specific{close_quotes}. The deletion was found in Benin and Sokoto, Nigeria in 2/54 Edo Bini, 1/2 Edo Ishan, 3/99 Hausa, 0/18 Fulani, and 0/16 other Nigerians. The deletion was also detected in 3/115 Ivory Coast natives from Abidjan. A 9 bp insertion (triplication) was observed in 1/115 Ivory Coast natives. The triplicated individual also possessed the Hae III 16517 site gain. The fragment containing the African deletion was sequenced and found to be identical in sequence to the Asian deletion region. D-loop sequence of nts 15975 to 00048 revealed that 2 of the 3 Ivory Coast deleted individuals and 1 of the 6 Nigerians deleted (Hausa) had a T-C transition at nt position 16189 which is common in New World-deleted individuals. These results raise the possibility that the occurrence of this deletion predates the separation of Asian and African populations from a common ancestral populations, or that the deletion has occurred more than once in human evolution. Either explanation requires that caution be exercised when using the 9 bp deletion as a population marker.

  16. The spatiotemporal pattern of earthworm community in the grass savannas of Lamto (Ivory Coast)

    PubMed Central

    Lavelle, Patrick

    2015-01-01

    Abstract Background The impact of earthworms on both soil physical properties and soil organic matter dynamics has been well documented (Lavelle and Spain 2001). There is a wealth of literature dedicated to the biological mechanisms at work or to empirical approaches based on field data. Assessing the functional role of a species or community implies establishing both time and space scales at which it is effectively the primary determinant of the process(es) at hand. In that context, space-time data analyses are powerful tools to process community data collected on numerous occasions but are, however, not widely disseminated in the community of ecologists. Although computer resources are available, one difficulty is that ad hoc field data are not always easily available which hinders the percolation of the methods. New information We provide the results of a 5 dates survey of earthworm community in a grass savanna of Lamto (Ivory Coast) conducted between 1995 and 1997. At each sampling date, earthworm community was assessed by hand-sorting a set of 100 soil monoliths distributed on a regular grid of 5 m mesh. These data were analyzed in Rossi (2003a) and are published here with the aim that they could be reanalyzed using new statistical tools (e.g. MEM analyses see Jiménez et al. 2014) or serve as example for researchers that train on space-time statistical methods. PMID:26696763

  17. The Sefwi-Como belt Ghana/Ivory Coast : a major crustal shear zone ?

    NASA Astrophysics Data System (ADS)

    Jessell, Mark

    2010-05-01

    The Palaeoproterozoic Sefwi-Como region that straddles Ghana and the Ivory Coast in West Africa has been characterised as resulting from a combination of compression and simple shear during late synkinematic leucogranite intrusion. The analysis of regional geophysical datasets allows us to better define the geometry of the major lithostratigraphic packages and their structural contacts in this region. This analysis reveals a series of well defined leucogranites intrusions enveloped by high strain zones. Recent finite element modelling of two-phase aggregates has shown that we can analyse the geometry of these systems both in terms of their finite defomation and their mechanical contrast. We interpret the geometries we see in the Sefwi-Como region as reflecting the activity of a major crustal deformation zone which was dominated by simple shear. The comparison with the modelling suggests a finite shear strain of approximately 5 gamma, which in turn implies a lateral displacement of 400 km across the belt. Our analysis suggests that the leucogranites were already acting as more rigid bodies during the (dextral?) shearing, suggesting that their emplacement was predominantly pre-kinematic, and which has implications for their potential subsequent remobilization by gravitational forces.

  18. Three-dimensional seismic interpretation: Espoir Field area, offshore Ivory Coast

    SciTech Connect

    Grillot, L.R.; Anderton, P.W.; Haselton, T.M.; Dermargne, J.F.

    1986-05-01

    The Espoir oil field, located approximately 13 km offshore Ivory Coast, was discovered in 1980 by a joint venture comprised of Phillips Petroleum Company, AGIP, SEDCO Energy, and PETROCI. Following the discovery, a three-dimensional seismic survey was recorded by GSI in 1981-1982 to provide detailed seismic coverage of Espoir field and adjacent features. The seismic program consisted of 7700 line-km of data acquired in a single survey area that is located on the edge of the continental shelf and extends into deep water. In comparison with previous two-dimensional seismic surveys, the three-dimensional data provided several improvements in interpretation and mapping including: (1) sharper definition of structural features, (2) reliable correlations of horizons and fault traces between closely spaced tracks, (3) detailed time contour maps from time-slice sections, and (4) improved velocity model for depth conversion. The improved mapping helped us identify additional well locations; the results of these wells compared favorably with the interpretation made prior to drilling.

  19. Regulation of business activities of petroleum contractors in Cameroon, Congo, Gabon, and Ivory Coast

    SciTech Connect

    Frilet, M.; Newman, J.

    1982-03-01

    Foreign companies engaging in business in Cameroon, Congo, Gabon, and Ivory Coast are subject to a broad range of regulations. This article deals only with those aspects of the regulations that are most important to petroleum contractors intending to engage in business in these countries. The regulator scheme actually applicable in a given case will depend on the legal structure through which a corporation operates. An American corporation may envisage engaging in business on a long-term basis through a local subsidiary or branch. On the other hand, it may wish only to perform temporary activities pursuant to one or more fixed-duration contracts with petroleum companies operating in one of countries. Each of these situations is dealt with. Common features of each area of regulation were described and the differences in regulations were presented. These topics were included: exchange control regulation, corporate forms of business association, authorization to engage in business, requirement of government or local participation in capital, investment code incentives, labor law requirements, taxation of corporations, taxation of profits, taxation of income from movable capital, taxation of amounts paid abroad as technical assistance fees, royalties and similar compensation, turnover taxes, payroll taxes, taxation of business performed without forming a local company or branch, taxation of employees and Social Security contributions. (DP)

  20. The Ivory Coast-Ghana transform margin: A marginal ridge structure deduced from seismic data

    NASA Astrophysics Data System (ADS)

    Basile, C.; Mascle, J.; Popoff, M.; Bouillin, J. P.; Mascle, G.

    1993-06-01

    The Ivory Coast-Ghana (ICG) marginal ridge is a prominent feature of the ICG transform margin and includes a fossil ridge partially buried by a thick, undeformed sedimentary cover. The fossil ICG ridge is 130 km long and 25 km wide, and towers over the adjacent rifted basin (deep Ivorian basin, DIB) and the oceanic crust by 1.3 km and more than 4 km, respectively. It formed in three successive stages. (1) During the rifting of the DIB, both vertical and horizontal motions between the DIB and the South American plate varied along the plate boundary. This relative motion occurred in an accommodation zone that tilted the northern slope of the ICG ridge along en-chelon, mainly strike-slip, faults. (2) After the rifting of the DIB, the relative motion remained constant along the transform plate boundary. At this time strike-slip deformation was localized into a narrow and highly deformed belt that truncated the accommodation zone. (3) Finally, the transform motion occurred between the DIB and an occanic plate. Thermal exchanges between the two adjacent plates induced thermal uplift of the ICG ridge that amplified previous tectonic tilting.

  1. Characterisation of Kaolinitic Clays from the Ivory Coast: Identification of Structural Fe

    NASA Astrophysics Data System (ADS)

    Sei, J.; Abba Tour, A.; Olivier-Fourcade, J.; Quiquampoix, H.; Staunton, S.; Jumas, J. C.; Womes, M.

    2004-09-01

    Five clays from four different deposits in the Ivory Coast (Adatti, Nieki, Grand-Bassam, Nigui-Saff) were studied by 57Fe Mssbauer spectroscopy and electron paramagnetic resonance (EPR) at room temperature. Their chemical compositions were determined by X-ray fluorescence and the most important crystalline phases were identified by X-ray diffraction. In these natural clays, kaolinite is the dominant mineral phase with minor amounts of other minerals including quartz, haematite, goethite, lepidocrocite and illite. Room-temperature 57Fe Mssbauer spectra of the samples from Nieki, Adatti and Nigui-Saff show mainly a broad quadrupole-split doublet which indicates that iron is essentially present as Fe(III). Samples from Grand-Bassam contain important amounts of goethite (?-FeOOH) and lepidocrocite (?-FeOOH). Some samples from Nigui-Saff contain large amounts of haematite. Clays from Nieki and Adatti are characterised by very low concentrations of iron oxides or hydroxides, and by small amounts of structural Fe(II) in the kaolinite lattice. Oxidation states and lattice sites of structural iron in the kaolinites were determined by 57Fe Mssbauer spectra recorded after iron extraction with dithionite-citrate-bicarbonate (DCB). The results were confirmed by electron paramagnetic resonance (EPR) measurements.

  2. Lithium in tektites and impact glasses: Implications for sources, histories and large impacts

    NASA Astrophysics Data System (ADS)

    Magna, T.; Deutsch, A.; Mezger, K.; Skla, R.; Seitz, H.-M.; Mizera, J.; ?anda, Z.; Adolph, L.

    2011-04-01

    Lithium (Li) abundances and isotope compositions were determined in a representative suite of tektites (moldavites, Muong Nong-type tektites and an australite, Ivory Coast tektites and bediasites), impact-related glasses (Libyan Desert Glass, zhamanshinites and irghizites), a glass fragment embedded in the suevite from the Ries impact crater and sedimentary materials in order to test a possible susceptibility of Li to fractionation during hypervelocity impact events and to de-convolve links to their potential parental sources. The overall data show a large spread in Li abundance (4.7-58 ppm Li) and ? 7Li values (-3.2 to 26.0) but individual groups of tektites and impact glasses have distinctive Li compositions. Most importantly, any significant high-temperature Li isotope fractionation can be excluded by comparing sedimentary lithologies from central Europe with moldavites. Instead, we suggest that Li isotope compositions in tektites and impact-related glasses are probably diagnostic of the precursor materials and their pre-impact geological histories. The Muong Nong-type tektites and australite specimen are identical in terms of Li concentrations and ? 7Li and we tentatively endorse their common origin in a single impact event. Evidence for low-temperature Rayleigh fractionation, which must have operated prior to impact-induced melting and solidification, is provided for a subset of Muong Nong-type tektites. Although Li isotope variations in most tektites are broadly similar to those of the upper continental crust, Libyan Desert Glass carries high ? 7Li ?24.7, which appears to mirror the previous fluvial history of parental material that was perhaps deposited in lacustrine environment or coastal seawater. Lithium isotopes in impact-related glasses from the Zhamanshin crater define a group distinct from all other samples and point to melting of chemically less evolved mafic lithologies, which is also consistent with their major and trace element patterns. Extreme shock pressures and the related extreme post-shock temperatures alone appear not to have any effect on the Li isotope systematics; therefore, useful information on parental lithologies and magmatic processes may be retrieved from analyses of Martian and lunar meteorites. Moreover, lack of significant Li depletion in tektites provides further constraints on the loss of moderately volatile elements during the Moon-forming impact.

  3. Impact of vertical structure on water mass circulation in a tropical lagoon (Ebri, Ivory Coast)

    NASA Astrophysics Data System (ADS)

    Brenon, Isabelle; Audouin, Olivier; Pouvreau, Nicolas; Maurin, Jean-Christophe

    2009-09-01

    A one-dimensional vertical model has been developed to simulate the water mass circulation along the vertical structure in all deep coastal areas. The model has hydrodynamic and transport components solved using finite difference scheme. The one-dimensional vertical model results are coupled to the vertically averaged two-dimensional model results at each point of a horizontal grid. A theoretical salinity profile is introduced for each vertically integrated value obtained from the 2DH model results. A viscosity profile, simulating a viscosity value close to zero at the surface and with large viscosity gradients, is applied along the water column. The model is applied to the Vridi channel, connecting the Ebri lagoon to the sea (Ivory Coast). The response of the Ebri lagoon is studied in terms of inflow and outflow of water in the system through the Vridi channel. Due to the abrupt variation of the surface slope, vertical velocities along the water column show an anticlockwise spiral from bottom to surface during a tidal cycle. Due to the bottom friction and to the vertical viscosity profile, velocities decrease from surface to bottom. However, the freshwater inflow slows down the tidal propagation during the flood and causes the surface velocity to be smaller than the bottom velocity at mid-tide. Close to the bottom, velocities follow an anticlockwise movement due to the tidal propagation. At the water surface, velocities follow only an alternative movement of either ebb or flood, along the channel direction. No cross shore velocities can develop at the surface in the channel.

  4. Survey of drug and phage resistance and colicin and hemolysin production among coliforms isolated in the Ivory Coast.

    PubMed Central

    Trudel, L; Arriaga-Alba, M; Lavoie, M C

    1984-01-01

    Analysis of 178 strains isolated as total and fecal coliforms in the Ivory Coast revealed that (i) hemolytic activity was scarce (0.6%) among this bacterial population; (ii) the most prevalent colicins detected were, in decreasing order, E, I, A, and G; (iii) the frequency of coliphage and drug resistance was similar to that observed in other countries, except for those of drug-resistant strains in animal feces, which were lower than in countries where animals are antibiotic fed; and (iv) one of the drug resistance plasmids seemed to possess a restriction-modification system and another seemed to code for capsular material. PMID:6095758

  5. Tektite controversy

    SciTech Connect

    Davis, J.

    1981-04-01

    Clues as to the possible origin of tektites are found by studying the chemical composition, sites where they are found, and shapes. An important chemical fact of tektites is that they are extremel dry. Tektites lie in four major areas and in three isolated regions. They are distributed as if they fell from the skies. By studying the flanged shapes of the australites, it was concluded that their shape was due to a fast, hot trip through the atmosphere. Tektites show no cosmic ray tracks which implies their space exposure time was short. This rules out the possibility that they are a form of meteorite with these clues in mind, four theories on their possible origin are discussed in this paper. The theories are: (1) terrestial impact by meteorite or comet; (2) lunar impact; (3) terrestial volcanoes; and (4) lunar volcanoes. This article rules out the first three theories for reasons which are given and leans toward the fourth theory as the most probable of the four. (SC)

  6. Living Kidney Donor Transplantation in a Resource-limited Country: The Ivory Coast Experience.

    PubMed

    Ackoundou-N'Guessan, C; Hoang, A D; Ben Abdallah, T; Gnionsahe, D A; Dollo, I; Ripoche, C; Coulibaly, N; Aye, D Y; N'Guessan, F Y; Diby Kouame, B; Guei, C M; Tia, M W; Amekoudji, Y; Lagou, D A

    2015-01-01

    Renal transplantation that offers a good quality of life still is not performed by the majority of countries of black Africa. We started a pilot project of renal transplantation in Ivory Coast 2 years ago. The present paper reports the preliminary results, difficulties related to the program, and perspectives regarding its expansion. Ten living related kidney transplantations have been performed over a 2-year period. Recipients and their respective donors were male. The mean age of the recipients was 42.8 years (22-57), and the mean age of the donors was 29.4 years (22-43). The mean number of mismatches was 3.2 (0-6). None was immunized. Recipients and donors were all EBV IgG positive and CMV IgG positive. All but 1 case were induced with basiliximab. The mean graft and patient survival time was 16.6 months (6-26). The mean cold ischemic time was 2.27 hours (1-3.32). The mean serum creatinine at discharge was 241.87 ?mol/L (115.18-1063.2), at 6 months was 117.20 ?mol/l (95.6-139.9), at 12 months was 104.55 ?mol/L (62.02-132.9), and at 24 months was 104.55 ?mol/L (62.02-132.9). The mean cyclosporine through level (C0) at 6 months was 137.57 ng/mL (70-366), at 12 months was 117.33 ng/mL (62-197), and at 24 months was 78 ng/mL. The mean cyclosporine 2-hour post-administration concentration levels (C2) at 6 months was 764.9 ng/mL (430-1421), at 12 months was 937.17 ng/mL (483-1292), and at 24 months was 690.66 ng/mL (488-853). Main complications were sepsis, adenovirus hemorrhagic cystitis, new-onset diabetes after transplantation, delayed graft function, polycythemia, and cytomegalovirus infection. No clinical rejection was diagnosed over the 2-year period. Patient and graft survival was 100% at a mean post-transplantation time of approximately 16.6 months. PMID:26293016

  7. Cost Analysis of Non-Formal ETV Systems: A Case Study of the "Extra-Scolaire" System in the Ivory Coast.

    ERIC Educational Resources Information Center

    Klees, Steven J.

    Building on previous evaluations of the ETV systems--both formal and informal--of the Ivory Coast, this study examines the system costs of the "Extra Scolaire" (E/S) program for rural adults. Educational television is utilized through the Ivorian primary system, and battery operated televisions have been widely distributed to schools in rural

  8. Sex, fertility and menstruation among the Beng of the Ivory Coast: a symbolic analysis.

    PubMed

    Gottlieb, A

    1982-01-01

    An attempt is made in this discussion to relocate the topic of menstruation in a new framework, one not directly defined by gender and not restricted to the view that menstrual blood and menstrual pollution are by definition viewed negatively. The Beng (Ivory Coast) notions of menstruation are explored as they relate to wider concepts of pollution and fertility. The analysis demonstrates how menstrual pollution among the Beng forms part of another type of pollution--the spatio symbolic pollution of human fertility when it is removed from its proper place--and how, rather than debasing women, menstruation serves to have added value to a major aspect of women's labor--that of cooking. There are 3 rules which Beng observe concerning menstruation: no initiated, married, or previously married woman who is menstruating may set foot in the forest for any reason other than to defecate; a menstruating woman may not touch a corpse; and a man may not eat food cooked by his wife during the days she is menstruating, nor may a Master of the Earth eat food cooked by any menstruating woman. At first, these taboos appear to be another case of the pollution of women through menstruation and another instance of women's oppression. When explored, the Master of Earth explained that menstrual blood is considered as special because it carries in it a living being and that menstrual blood is like the flower which must emerge before the fruit--the baby--can be born. No answer was provided to the question of pollution. There seemed to be no other rules specifying what activities a woman should or should not pursue during menstruation. She is not isolated from the flux of social life, and sexual activiity during menstruation, though not commonly done, is not taboo. The fact that it is only working in the forest, and not other activities, that is prohibited to menstruating women reveals that menstruation is not regarded as dangerous to men or as polluting in general. Rather, menstrual blood is seen as a symbol of human fertility, and for this reason is not allowed to touch the forest/fields, which are viewed as a form of Earth fertility. Forest/field fertility and village fertility must be conceptually kept apart, according to the Beng view of the world. Similarly, Beng husbands may not eat food cooked by their menstruating wives for a related reason. Menstruating women who cook are handling crops produced in the forest/fields, and their husbands, with whom they produce (village) children, must therefore avoid contact with such food, lest the 2 realms of village and forest fertility be mixed. Food cooked by menstruating women is agreed by all Beng to be the most delicious of all Beng food, thus giving positive value to an activity of menstruating women. PMID:12264952

  9. Cuban tektite revisited

    SciTech Connect

    Koeberl, C.

    1988-06-01

    Major-element and trace-element analyses were performed on the Cuban tectite, found about 20 years ago at Columbia University and classified by Garlick et al. (1971) as belonging to the North American tectite strewn field. The results indicate that the Cuban tektite is a North American tektite, but different from both bediasites and Georgia tektites, although with some similarities to bediasites. This tektite also has some similarities to the Barbados tektites, and, thus, may comprise its own distinct subgroup, probably related to the Barbados occurrence and belonging to a Caribbean substrewn field. It is concluded that the Cuban tektite really originated from Cuba. 32 references.

  10. Ivory Basements and Ivory Towers

    ERIC Educational Resources Information Center

    Fitzgerald, Tanya

    2012-01-01

    The metaphors of the ivory tower and ivory basement are used in this chapter to reflect how many women understand and experience the academy. The ivory tower signifies a place that is protected, a place of privilege and authority and a place removed from the outside world (and consequently the rigours of the market place). The ivory tower, by

  11. Prevalence of Newcastle disease virus and infectious bronchitis virus in avian influenza negative birds from live bird markets and backyard and commercial farms in Ivory-Coast.

    PubMed

    Kouakou, A V; Kouakou, V; Kouakou, C; Godji, P; Kouassi, A L; Krou, H A; Langeois, Q; Webby, R J; Ducatez, M F; Couacy-Hymann, E

    2015-10-01

    Newcastle disease (ND) and infectious bronchitis (IB) are two major viral diseases affecting the respiratory tracts of birds and whose impact on African poultry is still poorly known. In the present study we aimed at assessing NDV and IBV prevalences in Ivory-Coast by molecular screening of >22,000 avian swabs by nested PCR and by serology testing of close to 2000 avian sera from 2010 through 2012. The NDV and IBV seroprevalences over the study period reached 22% and 72%, respectively. We found 14.7% pooled swabs positive by PCR for NDV and 14.6% for IBV. Both pathogens are therefore endemic in Ivory-Coast. Economic losses associated with NDV and IBV infections still need to be evaluated. PMID:26412525

  12. A Cuban tektite

    USGS Publications Warehouse

    Garlick, G.D.; Naeser, C.W.; O'Neil, J.R.

    1971-01-01

    A large tektite from Cuba is classified with other North American tektites on the basis of its age. The major-element chemistry, oxygen isotopic composition, refractive index and density of the Cuban tektite are within the ranges exhibited by bediasites. ?? 1971.

  13. Effectiveness of hepatitis-B vaccination in Ivory Coast: the case of the Grand Bassam health district.

    PubMed

    Magoni, M; Ekra, K D; Aka, L N; Sita, K S; Kanga, K

    2009-09-01

    Ivory Coast has a high prevalence of infection with hepatitis B virus (HBV). The effects of a control programme based on the anti-HBV vaccine, which has formed part of the national Expanded Programme on Immunization (EPI) since 2000, have recently been evaluated in the country, for the first time. In this, cross-sectional investigation, two-stage cluster sampling stratified by age was used to assess the impact of the programme of universal childhood HBV vaccination in the Grand Bassam health district. The seroprevalences of carriage of the HBV surface antigen (HBsAg) and of antibodies to this antigen (HBsAb) and to the core antigen of HBV (HBcAb) were estimated among children aged 12-59 months and their mothers. Serology was successful for 1038 children (of 1172 in the original sample) and 836 mothers. Of the children enrolled, 46.8% had had a standard vaccination (completed before the age of 6 months, with the correct schedule), 4.6% had had no vaccination against HBV, and the rest had received incomplete or incorrectly timed vaccination. The prevalence of HBsAg carriage was 0.7% among the tested children and 9.9% among the tested mothers. The prevalence of seroprotection (i.e. an HBsAb titre of >10 mIU/ml), which was 74.2% overall, was strongly correlated with the number of vaccination doses, ranging from 16.7% in the unvaccinated infants to 85.5% in the children who had each received four doses. Circulation of the virus (indicated by seropositivity for HBcAb) was much higher among the unvaccinated children (10.4%) than the fully vaccinated ones (2.9%). The prevalences of both HBsAg and HBcAb were higher in rural areas, where vaccine coverage was relatively low, than in the urban areas. It appears that HBV vaccine is highly effective within the framework of the EPI in Ivory Coast, where it has already had a positive impact in reducing HBsAg carriage among children under 5 years of age. Improving vaccination coverage in the rural areas of the country is now a public-health priority. PMID:19695157

  14. [Specific diversity and culicidian nuisance in the villages of N'gatty and Allaba in laguna area of Ivory Coast].

    PubMed

    Fofana, D; Konan, K L; Djohan, V; Konan, Y L; Kon, A B; Doannio, J M C; N'goran, K E

    2010-12-01

    Entomological surveys were undertaken between June and December 2006 in N'gatty and Allaba. These villages are located in southern Ivory Coast in a laguna area in Dabou department. In these villages, there are large swampy areas, which have caused the multiplication of anthropophilic Culicidae. Mosquitoes have been collected at preimaginal stage at the time of the larval prospecting and at adult stage through human landing catch. Larval collections have been made using the classic method of "dipping". Larvae have been identified to the genus level. Then, they have been bred in the laboratory to identify adults. Adults collection has been made once a month during three consecutive nights by human landing catch inside houses. Adults have been identified to the specific level. Eight genera of mosquitoes have been collected in these two villages: Aedes, Anopheles, Coquillettidia, Culex, Eretmapodites, Mansonia, Toxorhynchites and Uranotaenia. Twenty-four species have been listed during this stu y. The genus Mansonia is the most predominant with 86% (N = 15,811) and 80% (N = 1,385), respectively, in N'gatty and Allaba. The average biting rate per day varies between N'gatty and Allaba. It is estimated to 308 bites per human per night (b/h/n) in N'gatty and 72 b/h/n in Allaba. In these villages, mosquito nuisance is mainly due to Mansonia with 264 b/h/n and 58 b/h/n, respectively, in N'gatty and Allaba. However, Anopheles gambiae s.l. average rate was 12 b/h/n in N'gatty and 2 b/h/n in Allaba. PMID:20632142

  15. Seasonal variability of carbon dioxide and methane in the rivers and lagoons of Ivory Coast (West Africa)

    NASA Astrophysics Data System (ADS)

    Kon, Y. J. M.; Abril, G.; Delille, B.; Borges, A. V.

    2009-04-01

    We report a data-set of carbon dioxide (CO2) and dissolved methane (CH4) in three rivers (Bia, Tano and Como) and five lagoons (Tendo, Aby, Ebri, Potou and Grand-Lahou) of Ivory Coast (West Africa), during the four main climatic seasons (high dry season, high rainy season, low dry season and low rainy season). The surface waters of the three rivers were oversaturated in CO2 and CH4 with respect to atmospheric equilibrium, the seasonal variability of CO2 and CH4 seemed to be largely controlled by dilution during the flooding period. The strong correlation of CH4 concentrations with the partial pressure of CO2 (pCO2) confirm the dominance of a continental sources (from soils) for both CO2 and CH4 in these rivers. The largest CH4 over-saturations and diffusive air-water CH4 fluxes were observed in the Tendo and Aby lagoons that are permanently stratified systems (unlike the other 3 lagoons), leading to anoxic bottom waters favorable for a large CH4 production. In addition, these two stratified lagoons showed low pCO2 values due to high primary production, which suggests an efficient transfer of organic matter across the pycnocline. As a result, the stratified Tendo and Aby lagoons were respectively, a low source of CO2 to the atmosphere and a sink of atmospheric CO2 while the other 3 well-mixed lagoons were strong sources of CO2 to the atmosphere but lower sources of CH4 to the atmosphere.

  16. Tektite Process Constraints

    NASA Astrophysics Data System (ADS)

    Harris, T. H. S.

    2015-07-01

    Shock accounts for only half of "australite" tektites 10 km/s morphologically derived speed. 5,000 m/s delta V remains unaccounted. In perspective, this is equivalent to ~50 years of geosynchronous station keeping budget, and 3/4 of the tektite's KE.

  17. Gases in Tektite Bubbles.

    PubMed

    O'keefe, J A; Lowman, P D; Dunning, K L

    1962-07-20

    Spectroscopic analysis of light produced by electrodeless discharge in a tektite bubble showed the main gases in the bubble to be neon, helium, and oxygen. The neon and helium have probably diffused in from the atmosphere, while the oxygen may be atmospheric gas incorporated in the tektite during its formation. PMID:17801113

  18. Palaeoclimatic and deforestation effect on the coastal fresh groundwater resources of SE Ivory Coast from isotopic and chemical evidence

    NASA Astrophysics Data System (ADS)

    Adiaffi, Bernard; Marlin, Christelle; Oga, Y Marie Solange; Massault, Marc; Noret, Aurelie; Biemi, Jean

    2009-05-01

    SummaryIn the South-east of the Ivory Coast, two aquifer systems have been studied in the sedimentary deposits at the South and in the fractured bedrock at the North of the study area (5-6N, 2.40-4.40W) : (1) the Continental Terminal (CT) and (2) the Paleoproterozoc Bedrock (PB). In the studied area, the vegetation cover has undergone significant changes since 1955 in addition to climate change. Rainforests have gradually disappeared due to natural and anthropological deforestation. The impact of deforestation on groundwater of the PB and on the CT has been studied by a geochemical approach. Stable isotopes ( 18O, 2H and 13C) contents, radiocarbon ( 14C) contents and chemical data (major ions) have been measured on a set of 25 groundwater samples. The residence time of the groundwaters is estimated with the 14C using two models: (i) the model of well-mixed reservoir (WMR model) and (ii) the piston flow model (PF model). The range of the PB groundwater residence time (15,200-8300 to 300-100 a BP) for both models shows that the recharge has started at the beginning of the post-glacial period whereas the CT aquifer recharge is much more recent (from 300 a BP to today). The PB groundwater provides information about paleoclimatic conditions that occurred over the studied area during the late Pleistocene. The low contents indicate cold and/or more humid conditions of recharge. During that period, the low content of 13C is consistent with a vegetation cover dominated by rainforest (C 3 plants). After the 20th century, the progressive evolution of vegetation cover from forest to cultivated plants and grasses is shown by the enrichment of groundwater in 13C (C 3 plants to C 4 plants). The relatively high mineralization level (mean of 143.7 mg L -1) and high ?18O- ?2H values of modern PB groundwater reflect of a recharge process that is slowed by a thick layer (16.3-72.5 m) of weathered formations above the PB formations. Groundwaters of the CT aquifer are constantly supplied by the fast infiltration of rainfall towards the water-table, explaining their very low total dissolved solids (TDS) of 20.1 mg L -1, their high 14C activities and their non-evaporated characteristics.

  19. Groundwater Pathways In Fractured Heterogeneous Granitic Aquifers - A Hydrochemistry Survey In The Sassandra Watershed (Inland Ivory Coast

    NASA Astrophysics Data System (ADS)

    Yao, T.; Fouche, O.

    2008-12-01

    Hydrogeochemical data and Landsat images are used to characterize the groundwater flow in a complex fractured granitic aquifer system located at the South-West of Ivory Coast (West Africa). The specific processing of the Landsat ETM+ images allows producing a detailed map of faults having length more than 3 km. The map is integrated with other data sources into a geographical information system (GIS) in order to identify areas favourable to groundwater sampling in fractured rock. The results of statistical analyses, as applied to hydrochemical data set clearly indicate that the groundwater of the study region is principally of Ca-Mg-HCO3 and Na-K-HCO3 types. The Ca-HCO3 type waters occur in areas of recharge (generally topographically higher area) i.e. where recharge occurs relatively fast. These waters generally have lower pH and EC values. The recharge occurs through preferential pathways such as alongside dykes and sills and the various fracture and joint patterns that transect the study area. The Na- HCO3 and Na-SO4 type waters occur in discharging and static regimes (the lower lying areas) where evaporation and cation exchange are the dominant processes. Ground waters are mostly oxidizing in character, and clearly unsaturated with respect to calcite, reflecting the small amount of carbonate in the aquifer. A few samples are reducing, with low NO3 and high dissolved Fe2+ and Mn2+ concentration and occur in the valley area. These reducing waters are thought to have experienced a deeper circulation and longer residence time in which reducing reactions have proceeded, with groundwater discharge along the valleys bottom. The chemistry of major ions, here applied to fractured aquifers, turns to be a powerful tool when carefully compared with a map of fault traces. We obtain a sufficient knowledge of the aquifer heterogeneity prior to realize a zoning of the region, based on cells with homogeneous hydrodynamic behaviour in which local permeability ellipses are computed. Thus, we characterize the geographical variability of the permeability anisotropy in this segment of the Sassandra watershed.

  20. Origin of tektites

    NASA Technical Reports Server (NTRS)

    O'Keefe, John A.

    1994-01-01

    The origin of tektites has been obscure because of the following dilemma. The application of physical principles to the data available on tektites points strongly to origin from one or more lunar volcanoes; but few glasses of tektite composition have hitherto been reported from the lunar samples. Instead, the lunar silicic glasses consist chiefly of a material very rich in K2O and poor in MgO. The ratio of K2O/MgO is higher in these glasses than in any tektites reported. The solution of the dilemma seems to come from the study of some recently discovered terrestrial deposits of tektite glass with high values of K2O/MgO at the Cretaceous Tertiary boundary. These glasses are found to be very vulnerable to crystallization into sandine or to alteration to smectite. These end products are known and are more abundant than any terrestrial deposits of tektite glass. It seems possible that, in fact, the moon produces tektite glass, mostly of the high K2O-low MgO type; but on Earth these deposits are destroyed. The much less abundant deposits with lower K and higher Mg are observed because they survive. Other objections to the lunar origin hypothesis appear to be answerable.

  1. Trace Element Data help Understanding the Origin of Lake Bosumtwi Crater Related Glass (Ivory Coast Tektites, Microtektites, Fall-Back Particles, Suevite Glass)

    NASA Astrophysics Data System (ADS)

    Deutsch, A.; Langenhorst, F.; Berndt, J.

    2015-09-01

    We report for the four internally rather homogeneous groups of glass (IVC, IVC-MT, BOT 12 [suevite], FBG) concentrations of major and 42 minor elements (in-situ data with LA-ICP-MS) as well as Sr-Nd, and DEGAS data.

  2. The tektite problem

    NASA Technical Reports Server (NTRS)

    Okeefe, J. A.

    1978-01-01

    Small glassy pebbles, called tektites, are found in widely scattered locations around the world. These tektites appear much like volcanic glass obsidian, but their chemical composition is different from that of any terrestrial lava and they contain far less water and none of obsidian's characteristic microcrystals. No one has ever found the mother lode of a field of tektites. They cannot, therefore, be the product of terrestrial volcanism. Recently acquired knowledge about the moon's surface confirms earlier indications that tektites cannot be bits of lunar soil propelled to the earth by the impact of meteorites on the moon. According to one of two remaining possibilities tektites are bits of terrestrial sedimentary rock excavated by meteorites striking the earth's surface, melted by the heat of impact, and congealed into glass as they travel above the atmosphere to the scattered sites where they are found. The other possibility is that tektites are the remains of gobs of lava fired at the earth by volcanic activity on the moon.

  3. The role of savannas in the terrestrial Si cycle: A case-study from Lamto, Ivory Coast

    NASA Astrophysics Data System (ADS)

    Alexandre, A. E.; Abbadie, L.

    2011-12-01

    Savannas currently occupy a fifth of the earth's land surface and are predicted to expand in the next few centuries at the expense of tropical forests, mainly as a result of deforestation and human fires. Can such a vegetation trend impact, through changes in plant Si cycling, the lithogenic silicon (LSi) release into soils (through chemical weathering) and the net dissolved Si (DSi) outputs from soils to stream water (through chemical denudation)? The first step of an investigation requires quantifying the net Si fluxes involved in the plant/soil system. Here, a schematic steady-state Si cycle, established for a tropical humid savanna (Lamto, Ivory Coast) that developed on a ferruginous soil and is subjected to annual fires, is presented. Erosion was assumed to be insignificant. LSi and biogenic Si (BSi under the form of phytoliths) pools were measured, and Si fluxes were estimated from Si concentrations and mass balance calculation. Identification of plant and soil phytoliths indicated that the soil BSi pool is in equilibrium with the current BSi input by the savanna. In the soil column, mixing between a young rapidly recycled BSi pool and an old stable BSi pool is attested by a mixing line equation. Storage of the old BSi pool is assimilated as a BSi output from the plant/soil system. A BSi output additionally occurs after annual fires, when ashes are exported. Both BSi outputs decrease as much the BSi dissolution. In order to uptake constant DSi flux, the savanna increases by three to eight times the net LSi release, depending upon the post-fire ash exportation scenario. A comparison between savanna and rainforest Si cycles that maximizes the differences in plant/soil systems and minimizes differences in climate is presented. The comparison revealed that BSi storage is higher in the savanna soil than in the rainforest soil, mainly due to BSi production that is twice higher in the savanna (127 vs 67 kg/ha/yr). The resulting LSi release that is enhanced by plant uptake is more than 1.5 higher in the savanna than in the rainforest (from 33 to 85 kg/ha/yr in the savanna vs 21 kg/ha/yr in the rainforest). On the contrary, DSi output from soils to stream water, which is not controlled by plant Si cycling but more likely by the soil hydrological regime (or meteoric weathering), is close to twice as high in the rainforest/ferrallitic soil ecosystem (16 vs 9 kg/ha/yr). This case study suggests that the predicted expansion of savannas at the expense of forests should significantly increase DSi uptake by plants, BSi storage in soils, BSi output with ash exportation, and, hence, LSi release through chemical weathering, without direct impact on DSi outputs from soils to stream water. Tracks for further assessing the role of plant Si cycling on chemical weathering, Si and C cycles were suggested: 1) estimates of BSi fluxes that were wrongly based on the assumption that the amount of DSi leached out from soils is linked to the magnitude of plant Si cycling and/or to BSi concentration in soils should be reappraised and 2) changes in the magnitude of plant Si cycling should be accounted in geochemical carbon cycle models, for one of the plant-induced weathering mechanisms.

  4. The role of savannas in the terrestrial Si cycle: A case-study from Lamto, Ivory Coast

    NASA Astrophysics Data System (ADS)

    Alexandre, Anne; Bouvet, Mickael; Abbadie, Luc

    2011-08-01

    Savannas currently occupy a fifth of the earth's land surface and are predicted to expand in the next few centuries at the expense of tropical forests, mainly as a result of deforestation and human fires. Can such a vegetation trend impact, through changes in plant Si cycling, the lithogenic silicon (LSi) release into soils (through chemical weathering) and the net dissolved Si (DSi) outputs from soils to stream water (through chemical denudation)? The first step of an investigation requires quantifying the net Si fluxes involved in the plant/soil system. Here, a schematic steady-state Si cycle, established for a tropical humid savanna (Lamto, Ivory Coast) that developed on a ferruginous soil and is subjected to annual fires, is presented. Erosion was assumed to be insignificant. LSi and biogenic Si (BSi under the form of phytoliths) pools were measured, and Si fluxes were estimated from Si concentrations and mass balance calculation. Identification of plant and soil phytoliths indicated that the soil BSi pool is in equilibrium with the current BSi input by the savanna. In the soil column, mixing between a young rapidly recycled BSi pool and an old stable BSi pool is attested by a mixing line equation. Storage of the old BSi pool is assimilated as a BSi output from the plant/soil system. A BSi output additionally occurs after annual fires, when ashes are exported. Both BSi outputs decrease as much the BSi dissolution. In order to uptake constant DSi flux, the savanna increases by three to eight times the net LSi release, depending upon the post-fire ash exportation scenario. A comparison between savanna and rainforest Si cycles that maximizes the differences in plant/soil systems and minimizes differences in climate is presented. The comparison revealed that BSi storage is higher in the savanna soil than in the rainforest soil, mainly due to BSi production that is twice higher in the savanna (127 vs 67 kg/ha/yr). The resulting LSi release that is enhanced by plant uptake is more than 1.5 higher in the savanna than in the rainforest (from 33 to 85 kg/ha/yr in the savanna vs 21 kg/ha/yr in the rainforest). On the contrary, DSi output from soils to stream water, which is not controlled by plant Si cycling but more likely by the soil hydrological regime (or meteoric weathering), is close to twice as high in the rainforest/ferrallitic soil ecosystem (16 vs 9 kg/ha/yr). This case study suggests that the predicted expansion of savannas at the expense of forests should significantly increase DSi uptake by plants, BSi storage in soils, BSi output with ash exportation, and, hence, LSi release through chemical weathering, without direct impact on DSi outputs from soils to stream water. Tracks for further assessing the role of plant Si cycling on chemical weathering, Si and C cycles were suggested: 1) estimates of BSi fluxes that were wrongly based on the assumption that the amount of DSi leached out from soils is linked to the magnitude of plant Si cycling and/or to BSi concentration in soils should be reappraised and 2) changes in the magnitude of plant Si cycling should be accounted in geochemical carbon cycle models, for one of the plant-induced weathering mechanisms.

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

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

    The character of mountain building processes in the Palaeoproterozoic times is subject to much debate. The local observation of Barrovian-type assemblages and high-pressure granulite relics in the Man Rise (Cte d'Ivoire), led some authors to argue that Eburnean (Palaeoproterozoic) reworking of the Archaean basement was achieved by modern-style thrust-dominated tectonics (e.g., Feybesse & Milsi, 1994). However, it has been suggested that crustal thickening and subsequent exhumation of high-pressure crustal rocks can be achieved by virtue of homogeneous, fold-dominated deformation of hot crustal domains even in Phanerozoic orogenic belts (e.g., Schulmann et al., 2002; 2008). We describe a mafic granulite of the Kouibli area (Archaean part of the Man Rise, western Ivory Coast) that displays a primary assemblage (M1) containing garnet, diopsidic clinopyroxene, red-brown pargasitic amphibole, plagioclase (andesine), rutile, ilmenite and quartz. This assemblage is associated with a subvertical regional foliation. Symplectites that develop at the expense of the M1 assemblage contain orthopyroxene, clinopyroxene, plagioclase (bytownite), green pargasitic amphibole, ilmenite and magnetite (M2). Multiequilibrium thermobarometric calculations and P-T pseudosections calculated with THERMOCALC suggest granulite-facies conditions of ca. 13 kbar, 850C and <7 kbar, 700-800C for M1 and M2, respectively. In agreement with the qualitative information obtained from reaction textures and chemical zoning of minerals, this suggests an evolution dominated by decompression accompanied by moderate cooling. A Sm-Nd garnet - whole-rock age of 2.03 Ga determined on this sample indicates that this evolution occurred during the Palaeoproterozoic. We argue that from the geodynamic point of view the observed features are best explained by homogeneous thickening of the margin of the Archaean craton, re-heated and softened due to the accretion of hot, juvenile Palaeoproterozoic crust, as well as coeval intrusion of juvenile magmas. Crustal shortening was mainly accommodated by transpressive shear zones and by lateral crustal spreading rather than large-scale thrust systems. The occurrence of high-pressure granulites does not imply thrust-dominated tectonics. Feybesse, J.-L. & Milsi, J.-P., 1994. The Archean/Proterozoic contact zone in West Africa: a mountain belt of dcollement thrusting and folding on a continental margin related to 2.1 Ga convergence of Archean cratons? Precambrian Research, 69, 199-227. Schulmann, K., Schaltegger, U., Jeek, J., et al. 2002. Rapid burial and exhumation during orogeny: thickening and synconvergent exhumation of thermally weakened and thinned crust (Variscan orogen in Western Europe). American Journal of Science, 302, 856-879. Schulmann, K., Lexa, O., tpsk, P. et al., 2008. Vertical extrusion and horizontal channel flow of orogenic lower crust: key exhumation mechanisms in large hot orogens? Journal of Metamorphic Geology, 26(2), 273-297.

  6. Phylogeny of the genus Willemia (Collembola: Hypogastruridae) and biogeography of the W. buddenbrocki-group with description of a new species from Ivory Coast (western Africa).

    PubMed

    Zon, Serge Dmango; Bedos, Anne; D'Haese, Cyrille A

    2015-01-01

    Willemia tondoh sp. nov. from the Ivory Coast (western Africa) is described and illustrated. The new species is the 14th in the buddenbrocki-group and is defined with two large globular sensilla placed in a cavity and covered in part by tegumental fold on antennal segment IV, 7 chaetae on antennal segment I, postantennal organ with 9 vesicles, s-chaetae subcylindrical and acuminate on abdominal terga and chaetae a1 absent on abdominal sternum IV. A phylogeny for all the 46 species of the genus Willemia is proposed. Based on the phylogentic framework, the biogeography of the buddenbrocki-group is discussed. An identification key for all 46 known species of the genus is provided. PMID:26249949

  7. Detrital Mineral Grains in Tektites.

    PubMed

    Bairnes, V E

    1963-12-27

    Abundant detrital crystalline mineral grains have been found in layered Muong Nong-type indochinite tektites from Nong Sapong, northeastern Thailand. These grains are an integral part of some tektite layers, and their presence furnishes strong presumptive evidence that indochinites, as well as other tektite groups in which layered specimens occur, formed from surficial earth materials. PMID:17834370

  8. Ivory Snowmen

    ERIC Educational Resources Information Center

    Mueller, Ann

    2005-01-01

    Recalling memories from her own third grade art classes, Ann Mueller, recreated an updated version for her students showing her students how to make snow scenes from Ivory Snow flakes. She showed students the video, The Snowman based on Raymond Briggs's book of the same name. Its beautiful images spur the imagination, and the musical score is

  9. Ivory Snowmen

    ERIC Educational Resources Information Center

    Mueller, Ann

    2005-01-01

    Recalling memories from her own third grade art classes, Ann Mueller, recreated an updated version for her students showing her students how to make snow scenes from Ivory Snow flakes. She showed students the video, The Snowman based on Raymond Briggs's book of the same name. Its beautiful images spur the imagination, and the musical score is…

  10. Origin of Tektites.

    PubMed

    O'keefe, J A; Shute, B E

    1963-03-29

    A comet of the size recently postulated by H. C. Urey would leave a large crater. It is shown, from aerodynamic theory, from observations of distribution around terrestrial impact craters, and from experimental nuclear explosions, that the observed distribution of tektites cannot be the result of impact on the earth, whether cometary or meteoritic. It is further shown, from aerodynamic theory, from observation of a meteor shower, and from study of the breakup of artificial satellites, that the distribution of tektites can be accounted for as a result of fusion stripping of a satellite, as originally suggested by Suess. PMID:17757065

  11. Assessment of Mycotoxin Exposure in Cte divoire (Ivory Coast) Through Multi-Biomarker Analysis and Possible Correlation with Food Consumption Patterns

    PubMed Central

    Kouadio, James Halbin; Lattanzio, Veronica M. T.; Ouattara, Djeneba; Kouakou, Brou; Visconti, Angelo

    2014-01-01

    Scope: The aim of the presented study was to investigate the mycotoxin exposure of Ivorian population related to the consumption patterns of maize, peanuts, millet, and cassava product (attik). Materials and Methods: Maize flour samples (n = 51) were purchased from all Abidjan local markets, in the south of Ivory Coast, and urine (n = 99) was collected during the same reference period (JulySeptember 2011) from volunteers living in Abidjan and Daloa cities. Reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC-ESI-MS/MS) was used to analyze aflatoxins (AFB1, AFB2, AFG1, and AFG2), ochratoxin A (OTA), fumonisins (FB1, FB2), deoxynivalenol (DON), zearalenone (ZEA), and T-2 and HT-2 toxins in maize flour samples, and their relevant biomarkers (AFM1, DON, DON + de-epoxydeoxynivalenol (DOM-1), FB1, ?-zearalenol (ZOL), ?-ZOL, and OTA) in urine samples. Results: Critical maize contamination was observed by AFs occurrence (total AFs 4.5 330.0 ?g/kg) while OTA was found in 13% of samples analyzed. AFM1 was detected in 40% of urines samples (0.06 14.11 ng/ml), OTA in 37% (0.01 0.42 ng/ml), FB1 in 27% (0.07 to 15.31 ng/ml) and, DON was found in 21% of samples at levels up to 10.0 ng/ml. The correlation coefficients (R2) obtained by plotting the percentage of biomarker occurrence (positive samples) versus the frequency of food consumption revealed maize, peanuts, millet and attik were strongly linked to AFB1 and OTA exposure with values of R2 ranged from 0.462 to 0.956. Conclusion: The present study provided data on mycotoxin risk in Ivory Coast, revealing a frequent co-exposure to the major mycotoxins such as AFs, OTA, and fumonisins, which appeared to be related to the frequency of peanuts, maize, millet and attik consumption. PMID:25948962

  12. Paleoclimatic and deforestation effect on the chemical and isotopic composition of the coastal fresh groundwater resources of South-east Ivory Coast

    NASA Astrophysics Data System (ADS)

    Adiaffi, B.; Marlin, C.; Yei, O. M.-S.; Massault, M.; Noret, A.; Biemi, J.

    2009-04-01

    Since a half of century, the forest surface area of the South Ivory Coast has been decreased for the benefit of agriculture (15 000 km2 in 1993 versus 83 000 km2 in 1955-1958). This area also undergoes climate change. Vegetation cover has gradually changed from rainforests (C3 plants) to savanna (C4 plants) and agricultural plants. In the Abidjan area (5.00-6.00N, 2.40-4.40W), the mean rainfall amount and temperature value evolve during the 20th century (1912 mm/year and 26.3C/year during the first decennial to 1613 mm/year and 26.9C/year during the last ten years). The Paleoproterozoc fractured bedrock (PB) and the Continental Terminal (CT) deposits groundwater are studied to show the climate change and deforestation effect on the area groundwater resources using stable isotopes (18O, 2H and 13C) contents, radiocarbon (14C) contents and chemical data on a set of 25 groundwater samples. The residence time of the groundwaters is estimated by the 14C using two models: (i) the model of well-mixed reservoir (WMR model) and (ii) the piston flow model (PF model). The range of the PB groundwater residence time (15 000 - 8 000 to ~ 300 - 100 a BP) for both models shows that the recharge has started at the beginning of the post-glacial period whereas the CT aquifer recharge is much more recent (from 300 a BP to today). The PB groundwater provides information about paleoclimatic conditions that occurred over the studied area during the late Pleistocene. It is demonstrated, through this study, that the evolution of vegetation cover (from forests to savanna and agriculture plants) is shown in groundwater by the trend in 13C content from old groundwater (confined bedrock groundwater: residence time of ~ 15 000 a BP) to the recent groundwater (unconfined bedrock groundwater and CT groundwater: residence times: ~ 300 a BP and lower than 100 a BP, respectively). The ?18O and ?2H values also increase with time from the beginning of the post-glacial period (~ 15 000 a BP) to the present day (< 100 a BP), showing the evolution of the climate from cold to warm conditions. This study has shown the paleoclimate effect on the water resources in Ivory Coast and are consistent with the results obtained by some authors in Western Africa (Ghana, Liberia, Mali and Niger).

  13. Layered tektites - A multiple impact origin for the Australasian tektites

    NASA Astrophysics Data System (ADS)

    Wasson, J. T.

    1991-02-01

    The mechanisms proposed for the origin of tektites from the Australasian field are examined using neutron activation data for twenty layered tektites and six splash tektites of known and widely separated sites of a field greater than 1140 km in length. Evidence is presented indicating that the layered tektites formed as sheets or pools of melt. It is argued that their distribution across a field greater than 1140 km in length is inconsistent with their formation in a single crater, and that many impact craters are required to account for their distribution across such a large field.

  14. Sensitivity and Specificity of Human Immunodeficiency Virus Rapid Serologic Assays and Testing Algorithms in an Antenatal Clinic in Abidjan, Ivory Coast

    PubMed Central

    Koblavi-Dème, Stéphania; Maurice, Chantal; Yavo, Daniel; Sibailly, Toussaint S.; N′guessan, Kabran; Kamelan-Tano, Yvonne; Wiktor, Stefan Z.; Roels, Thierry H.; Chorba, Terence; Nkengasong, John N.

    2001-01-01

    To evaluate serologic testing algorithms for human immunodeficiency virus (HIV) based on a combination of rapid assays among persons with HIV-1 (non-B subtypes) infection, HIV-2 infection, and HIV-1–HIV-2 dual infections in Abidjan, Ivory Coast, a total of 1,216 sera with known HIV serologic status were used to evaluate the sensitivity and specificity of four rapid assays: Determine HIV-1/2, Capillus HIV-1/HIV-2, HIV-SPOT, and Genie II HIV-1/HIV-2. Two serum panels obtained from patients recently infected with HIV-1 subtypes B and non-B were also included. Based on sensitivity and specificity, three of the four rapid assays were evaluated prospectively in parallel (serum samples tested by two simultaneous rapid assays) and serial (serum samples tested by two consecutive rapid assays) testing algorithms. All assays were 100% sensitive, and specificities ranged from 99.4 to 100%. In the prospective evaluation, both the parallel and serial algorithms were 100% sensitive and specific. Our results suggest that rapid assays have high sensitivity and specificity and, when used in parallel or serial testing algorithms, yield results similar to those of enzyme-linked immunosorbent assay-based testing strategies. HIV serodiagnosis based on rapid assays may be a valuable alternative in implementing HIV prevention and surveillance programs in areas where sophisticated laboratories are difficult to establish. PMID:11325995

  15. Sex and age differences in the diet and ingestive behaviors of sooty mangabeys (Cercocebus atys) in the Tai Forest, Ivory Coast.

    PubMed

    McGraw, W Scott; Vick, Anna E; Daegling, David J

    2011-01-01

    Members of the Cercocebus-Mandrillus clade are united by several morphological features, including expanded premolars which are argued to be associated with a preponderance of hard objects in the diet. We test the association between premolar expansion and hard object feeding by examining how different dental regions are used during food processing. We examined the diet and oral processing activities of sooty mangabeys (Cercocebus atys) in the Ivory Coast's Tai forest from August 2008 to September 2009. In addition to compiling diet profiles, we recorded the frequency that individuals performed four activities: 1) incising, 2) canine puncturing/scraping, 3) postcanine crushing (i.e., isometric biting), and 4) routine mastication (chewing cycles). Sooty mangabeys have a relatively narrow diet that consists largely of nuts/seeds, fruits, and invertebrates. While there are age and sex differences in diet, the most frequently consumed foods are similar across age and sex classes. The most frequently consumed foods are seeds of Sacoglottis gabonensis which are the hardest items in the sooty mangabey diet. Patterns of ingestive behavior vary with food type, but adults and nonadults (excluding infants dependent on mothers) of both sexes process similar foods. Premolar expansion in Cercocebus atys is associated with powerful crushing of hard objects of specific size and durophagy is a constant feature of sooty mangabey feeding ecology throughout ontogeny. PMID:20925080

  16. [Control of the quality of water in the framework of a national rural water program on the Ivory Coast. Preliminary results].

    PubMed

    Viens, P; Lavoie, M

    1982-01-01

    In the framework of a National Hydraulic Village Program (NHVP) which aim is to equip each village of the Ivory Coast with wells or drillings, a water quality control service was designed, directly on the field, at the Health Rural Sector Bases. The standards of drinkability were revised according to the NHVP constraints. The technics used were adapted to local conditions. Sanitary education was part of the technics used by the field agents. 1,553 wells were analysed by the end of 1978, 17.7% of which were "polluted". Pollution was transient without treatment in 68% of the above cases. The most polluted cases had a rate of fecal coliforms a 1,000 time inferior to the average traditional wells. The drillings were less polluted (10%) than the large diameter wells (24%): in the latter there was a direct correlation between rain fall and pollution. The technical visits by the agents in the villages represented privileged moments of sensibilisation and education of the villagers. PMID:6286162

  17. Emissions and concentrations of hydrogen sulfide in the air of the tropical forest of the Ivory Coast and of temperate regions in France

    SciTech Connect

    Delmas, R.; Baudet, J.; Servant, J.; Baziard, Y.

    1980-08-20

    Atmospheric H/sub 2/S was measured by a fluorometric method (sensitivity 10 ng). In France, for aerated soils the emissions were between 0.8 and 27 ..mu..g m/sup -2/ h/sup -1/ H/sub 2/S (average 5 ..mu..g m/sup -2/ h/sup -1/). The soil temperature is an important factor governing this emission. The H/sub 2/S concentrations in the air ranged from 0.017 to 0.17 ..mu..g m/sup -3/ (average 0.080 ..mu..g m/sup -3/). In the Ivory Coast the H/sub 2/S emissions were estimated between 30 and 300 ..mu..g m/sup -2/ h/sup -1/. The measured concentrations of H/sub 2/S in the air at ground level ranged from 0.10 to 8.7 ..mu..g m/sup -3/. The relative importance of the measured emissions for anoxic soils of the humid equatorial forests in the global S cycle is discussed.

  18. Australasian tektites: source parameters and crater location reviewed

    NASA Astrophysics Data System (ADS)

    Stecher, O.; Storey, M.; Hopper, J. R.

    2009-12-01

    Tektites of the Australasian strewn field cover an area from SE-Asia, through the Southwestern part of the Pacific Ocean and parts of the Indian Ocean, down to Australia. The impact crater has until now not been positively located, but it is generally assumed to be located somewhere in Indochina, where tektites also are more abundant and larger. 40Ar/39Ar dated Australasian tektites consistently give ages around 800 ka (1,2), and our new laser step-heating determinations on a Thailand tektite are in agreement. Australasian tektites show a marked coherence in physical, chemical and isotopic parameters. Refractive indices of tektite fragments, numbers of vesicles, abundance of relict minerals, tektite mass/m2, major elements compositions from tektites covering the whole strewn field can be contoured with more or less elliptical curves with slightly varying center positions, located within a few 100 km of the Cambodia, Laos, Vietnam junction. Isotope data suggest that sediments of the impact area consisted of ~1500 Ma old denudation material (Nd-isotope data (3,4)) and that this material was eroded within the last 170 Ma (Sr-isotope data (3,4)). Fine-grained minerals and particularly soils are effective scavengers of cosmogenic 10Be, and the high values reported for Australasian tektites (5) suggest that clay minerals are a significant and variable component in the target material. The highest 10Be-values are from tektites found furthest from the impact site. In the impact process, the top layer of the target - with its young sedimentation ages and higher 10Be values - will be projected the furthest away from the impact site. The next layer down consists of slightly older material with lower 10Be, and the impact process will propel these tektites to areas closer to the impact site. The 10Be distribution in tektites shows this variation and defines a broad center (~17N, ~107E) off the coast of Vietnam (5). La-ICPMS Pb/Pb-isotope data from tektites show small progressive variations from Australia over Java to Thailand, and when these data are compared to determined Pb/Pb-isotope data from sediments from the Pearl River (S. China) and the Mekong River (S.Vietnam)(6) the data project towards the Mekong River suggesting that the crater could be found nearer to the Mekong River delta. Schnetzler et al. (7) using early Seasat/Geos3 satellite data first reported the possibility of a large crater off the coast of Vietnam (~13.8N, ~110.6 E). We have examined satellite bathymetry and gravity data for a large section of off-shore Vietnam, and we located a near circular feature at essentially the same position. The structure has a diameter of approximately 100 km, with a center at (~13.6N, ~111.2 E), and a peak rises more than 500 m above the crater floor. We concur with Schnetzler et al. (7) that this structure is most likely the impact site for Australasian tektites. (1) Yamei et al., Science 287, p1622 (2000) (2) Lo et al., MAPS, 37, p1555 (2002)) (3) Blum et al., GCA 56, p483 (1992) (4) Shaw and Wasserburg, EPSL 60, p155 (1982) (5) Ma et al., GCA 68, p3883 (2004) (6) Millot et al., Chem Geol, 203, p75 (2004) (7) Schnetzler et al., GRL 15, p357 (1988)

  19. The Origin of Tektites

    NASA Technical Reports Server (NTRS)

    OKeefe, J. A.

    1960-01-01

    Tektites are probably extraterrestrial, rather than the result of heating some terrestrial materials, because they are a chemically homogeneous group with definite peculiarities (high silica, excess of alkaline earths over alkalis, excess of potash over soda, absence of water), and because some of them (the australites) appear to have undergone ablation in flight through the atmosphere. Since comparatively slow heating is required to explain the liquefaction of the tektite material, it is suggested that the tektites arrived along orbits which were nearly parallel to the surface of the earth, and which resulted from the decay of the orbit of a natural satellite. The great meteor procession of February 9, 1913, is an example of such an object. Comparison with the reentry phenomena of the artificial satellite 1957 Beta suggests that the 1913 shower consisted of a single large stone weighing about 400 kilograms, and a few dozen smaller bodies weighing about 40 grams each, formed by ablation from the larger body. It is shown that under the observed conditions considerable liquid flow would be expected in the stone, which would be heated to about 2100 K. Objects falling from such a shower near the perigee point of the orbit would have a considerable distribution along the orbit as a result of slight variations in height or drag coefficient. The distribution in longitude would be made wider by the turning of the earth under the orbit during the time of fall. The ultimate source of the body which produces a tektite shower is probably the moon, which appears, by virtue of its polarization and the phase distribution of the returned light, to contain high-silica materials. It is suggested that the Igast object alleged to have fallen in 1855 is in fact genuine and represents an unmelted portion of the lunar crust.

  20. Beryllium-10 in Australasian tektites: Constraints on the location of the source crater

    NASA Astrophysics Data System (ADS)

    Ma, P.; Aggrey, K.; Tonzola, C.; Schnabel, C.; de Nicola, P.; Herzog, G. F.; Wasson, J. T.; Glass, B. P.; Brown, L.; Tera, F.; Middleton, R.; Klein, J.

    2004-10-01

    By using accelerator mass spectrometry we have measured the 10Be concentrations of 86 Australasian tektites. Corrected to the time of tektite production ˜0.8 My ago, the 10Be concentrations (10 6 atom/g) range from 59 for a layered tektite from Huai Sai, Thailand, to 280 for an australite from New South Wales, Australia. The average value is 143 ± 50. When tektites are sorted by country, their average measured 10Be concentrations increase slowly with increasing distance from Southeast Asia, the probable location of the tektite producing event, from 59 ± 9 for 6 layered tektites from Laos to 136 ± 20 for 20 splash-form tektites from Australia. The lowest 10Be concentrations for tektites fall on or within a contour centered off the shore of Vietnam, south of the Gulf of Tonkin (107°E; 17°N), but also encompassing two other locations in the area of northeastern Thailand previously proposed for the site of a single tektite-producing impact. The 10Be concentrations of layered tektites show only a weak anticorrelation (R ˜ -0.3) with the numbers of relict crystalline inclusions. Loosely consolidated, fine-grained terrestrial sediments or recently consolidated sedimentary rocks are the most likely precursor materials. Dilution of sediments with other kinds of rock raises problems in mixing and is not supported by petrographic data. Sedimentary columns that have the right range of 10Be concentrations occur off the coasts of places where sedimentation rates are high relative to those in the deep sea. A single impact into such a region, 15 to 300 m thick, could have propelled near-surface, high- 10Be material farthest—to Australia—while keeping the deeper-lying, low- 10Be layers closer to home. We do not rule out, however, other proposed mechanisms for tektite formation.

  1. Tektite glass in apollo 12 sample.

    PubMed

    O'keefe, J A

    1970-06-01

    The glassy portion of lunar sample 12013 from Apollo 12 is chemically more like some tektites from Java than like any terrestrial igneous rock. It satisfies all the chemical criteria for a tektite. Tektites are relatively recent and acid rocks, whereas the moon is chiefly ancient and basaltic; hence, tektites are probably ejected volcanically, rather than by impact, from the moon. PMID:17843588

  2. Georgiaites: Tektites in Central Georgia.

    ERIC Educational Resources Information Center

    Albin, Edward F.

    1991-01-01

    Information is provided about the origin, the features, and the availability of tektites which are odd and very rare types of transparent glass theorized to be from a common, yet unknown, origin. The basis for this article is the Howard collection of tektites found in a small region of central Georgia. (seven references) (JJK)

  3. Comparison of the bacterial species diversity of spontaneous cocoa bean fermentations carried out at selected farms in Ivory Coast and Brazil.

    PubMed

    Papalexandratou, Zoi; Camu, Nicholas; Falony, Gwen; De Vuyst, Luc

    2011-08-01

    To compare the spontaneous cocoa bean fermentation process carried out in different cocoa-producing regions, heap and box (one Ivorian farm) and box (two Brazilian farms) fermentations were carried out. All fermentations were studied through a multiphasic approach. In general, the temperature inside the fermenting mass increased throughout all fermentations and reached end-values of 42-48 C. The main end-products of pulp carbohydrate catabolism were ethanol, lactic acid, acetic acid, and/or mannitol. In the case of the fermentations on the selected Ivorian farm, the species diversity of lactic acid bacteria (LAB) and acetic acid bacteria (AAB) was restricted. Lactobacillus fermentum and Leuconostoc pseudomesenteroides were the predominant LAB species, due to their ethanol and acid tolerance and citrate consumption. The levels of mannitol, ascribed to growth of L. fermentum, were fermentation-dependent. Also, enterobacterial species, such as Erwinia soli and Pantoea sp., were among the predominating microbiota during the early stages of both heap and box fermentations in Ivory Coast, which could be responsible for gluconic acid production. Consumption of gluconic acid at the initial phases of the Ivorian fermentations could be due to yeast growth. A wider microbial species diversity throughout the fermentation process was seen in the case of the box fermentations on the selected Brazilian farms, which differed, amongst other factors, regarding pod/bean selection on these farms as compared to fermentations on the selected Ivorian farm. This microbiota included Lactobacillus plantarum, Lactobacillus durianis, L. fermentum, Lactobacillus mali, Lactobacillus nagelii, L. pseudomesenteroides, and Pediococcus acidilactici, as well as Bacillus subtilis that was present at late fermentation, when the temperature inside the fermenting mass reached values higher than 50 C. Moreover, AAB seemed to dominate the Brazilian box fermentations studied, explaining higher acetic acid concentrations in the pulp and the beans. To conclude, it turned out that the species diversity and community dynamics, influenced by local operational practices, in particular pod/bean selection, impact the quality of fermented cocoa beans. PMID:21569940

  4. Tektite 2 habitability research program

    NASA Technical Reports Server (NTRS)

    Nowlis, D. P.; Wortz, E. C.; Watters, H.

    1972-01-01

    Multi-level parameters relating to perceived life quality in an isolated research and residence quarters were measured using a variety of tests. The habitat under study, emplaced beneath the sea off the coast of St. John's Island as a part of the Tektite II program, was being used for marine research. The crew for each of the 10 missions consisted of one engineer and 4 scientists. One mission had an all-female crew. Mission length was either 14 or 20 days, and 4 engineers, in covering 6 missions, stayed in the habitat for periods of 30 days each. A personality test was taken before confinement in the habitat. Two attitude tests were filled out by the aquanauts while they were still in the habitat. Daily moods were monitored during all missions. Special observations were made of leisure time use. Standardized private debriefings were administered at the end of each mission to each aquanaut. Other behavioral observations made by another research team were intercorrelated with the other measures described above.

  5. Tektite ablation - Some confirming calculations.

    NASA Technical Reports Server (NTRS)

    O'Keefe, J. A., III; Silver, A. D.; Cameron, W. S.; Adams , E. W.; Warmbrod, J. D.

    1973-01-01

    The calculation of tektite ablation has been redone, taking into account transient effects, internal radiation, melting and nonequilibrium vaporization of the glass, and the drag effect of the flanges. It is found that the results confirm the earlier calculations of Chapman and his group and of Adams and his co-workers. The general trend of the results is not sensitive to reasonable changes of the physical parameters. The ablation is predominantly by melting rather than by vaporization at all velocities up to 11 km/sec; this is surprising in view of the lack of detectable melt flow in most tektites. Chemical effects have not been considered.

  6. Tektites and their origin. [properties and distribution

    NASA Technical Reports Server (NTRS)

    Okeefe, J. A.

    1975-01-01

    A study was conducted of the literature pertaining to the origin and characteristics of tektites. Topics discussed include tektite distribution in geographical locations, shapes of tektites, internal structure of tektites, physical properties, mechanical properties, optical properties, chemical composition, and comparisons with compositions of impact materials. Various arguments are presented on the terrestrial origin of tektites. It was found that some lunar craters of considerable size must be the products of volcanism which occurred during the past few million years, and that the moon must have within it a reservoir of rock which is considerably more like the mantle of the earth than like the rocks from which the basalts of the lunar crust are derived.

  7. Submicroscopic spherules and color of tektites

    USGS Publications Warehouse

    Thorpe, A.N.; Senftle, F.E.

    1964-01-01

    Magnetic susceptibility measurements of 18 tektites from various strewn fields have been made as a function of temperature from 77??K to room temperature. A relatively large temperature-independent component of the magnetic susceptibility was observed in all cases, and an analysis of the data shows that this component is the result of submicroscopic iron spherules in the tektites. An analysis of the color of tektites in terms of the magnetic measurements and also of the optical absorption spectra suggests that the basic color of all tektites is green or greenish-blue, and that the brown to black coloration in some tektites is due to finely dispersed Fe2O3 and/or many metallic spherules, both probably of colloidal size. ?? 1964.

  8. Fe-57 Moessbauer study of tektites

    NASA Technical Reports Server (NTRS)

    Evans, B. J.; Leung, L. K.

    1976-01-01

    Moessbauer measurements were made on selected moldavite, australite, philippinite, and Georgia tektites. The spectra consist of two apparent lines, but at least two quadrupole doublets can be fitted to these spectra. The Moessbauer parameters for these doublets indicate that they arise from Fe2+ ions with local environments, which are relatively rich and relatively poor in calcium, respectively, similar to those in clinopyroxenes. No evidence for Fe3+/Fe2+ ratios above 0.01 (estimated detection limit) have been found in any tektite. Tektites are considerably more reduced than previously believed, and the extent of the reduction shows little or no variation among different types of tektites. These results limit the source materials of tektites to minerals in which the iron is uniformly highly reduced and in which the iron is contained clinopyroxene-like phases.

  9. An Ordinary Chondrite Impactor Composition for the Bosumtwi Impact Structure, Ghana, West Africa: Discussion of Siderophile Element Contents and Os and Cr Isotope Data

    NASA Technical Reports Server (NTRS)

    Koeberl, Christian; Shukolyukov, Alex; Lugmair, Guenter

    2004-01-01

    Osmium isotope data had shown that Ivory Coast tektites contain an extraterrestrial component, but do not allow distinction between chondritic and iron meteorite contamination. PGE abundances of Ivory Coast tektites and impactites and target rocks from the Bosumtwi crater, the source crater of the Ivory Coast tektites, were all relatively high and did not allow to resolve the presence, or identify the nature, of the meteoritic component. However, Cr isotope analyses of an Ivory Coast tektite yielded a distinct 53Cr excess of 0.30+/-0.06, which indicates that the Bosumtwi impactor was an ordinary chondrite.

  10. Chemical systematics among the moldavite tektites

    NASA Technical Reports Server (NTRS)

    Delano, J. W.; Lindsley, D. H.

    1982-01-01

    The compositional variations that occur among the moldavite tektites are caused principally by incomplete mixing of two components during fusion. With the possible exception of silica, there is no evidence for significant losses of volatile species by fractional vaporization. Chemical constraints have been calculated for the two source-materials that contributed to the moldavites. If these tektites were formed by impact fusion, as is commonly believed, then the compositional systematics preserved within the moldavites suggest that hypersonic flow and ejection of impact melts are orderly processes. Insights gained from the study of tektites should prove useful in interpreting the chemistries of impact glasses from other bodies in the solar system.

  11. Muong-Nong-type tektites -- zhamanshinites: The longest differentiated tektite series

    NASA Astrophysics Data System (ADS)

    Izokh, E. P.

    1994-07-01

    Coexistence of three unmixed types of melted glasses (basic impactites, tektites-irghizites associated with microtektites, and multiple-layered Muong-Nong (MN)-type tektites - zhamanshinites) is a unique feature of the Zhamanshin impact crater. The crater represents the best test ground for solving the old tektite puzzle. MN-zhamanshinites can be arranged into the distinctly differentiated series, the longest tektite series recorded. Its acid make-up (70-85% SiO), composed of black glass is undistinguishable from the MN tektites common in Vietnam and Thailand. The middle part of the series (63-70% SiO) consists of yellow glass and pumice often interlaced with black acid glass. Close analogs of these black-yellow-layered MN tektites are found in Vietnam and Thailand. The low-silica part (50-60% SiO) consists of dark pumice unusually rich in AlO. All three members of the MN tektite series can be observed within large blocks more than 50 kg in weight, the fragments of some larger bodies like lava flows or extrusives unknown within the crater. The arguments in favor of extraterrestrial origin of the Zhamanshin MN tektite series are the age paradox; the absence of target rock compositional analogs, especially for the basic and intermediate part of the series; and findings of the MN-type zhamanshinites partially remelted during the last stages of the impact event. Evidence of volcanic origin is well-ordered differentiation trends typical of igneous rock series but not of impact melts; features of long-time multiphase formation of the layered MN tektites; distinct subseries or tektite families as possible products of different volcanic phases or impulses; and accumulation of glasses with various radiogenic ages in one place, impossible for an impact process but common for long-time volcanic activity. MN-type zhamanshinites are erroneously nominated as impactites by the advocates of the earth impact theory of tektite origin.

  12. Study of the ablative effects on tektite

    NASA Technical Reports Server (NTRS)

    Chen, K. K.

    1975-01-01

    The tumbling and surface roughness effects on the trajectory of entry tektite are studied in both free molecular and continuum flows. It was concluded that, while surface roughness has negligible effect on trajectory, the tumbling may play an important role in tektite trajectory and the consequent ablation, provided the body shape is different from a sphere. A shape factor was a good parameter for correlations between body shape and tumbling effects.

  13. Search for carbon 14 in tektites.

    NASA Technical Reports Server (NTRS)

    Boeckl, R. S.

    1972-01-01

    An attempt was made to detect cosmic-ray produced C-14 in australites and far-east tektites. No C-14 activity was found outside of statistical fluctuations. If a terrestrial age of 10 thousand years is assumed for australites, a maximum cosmic-ray exposure time of one thousand years is obtained for these tektites on the basis of a 2-sigma statistical error.

  14. Comparison of the effect of two excipients (karite nut butter and vaseline) on the efficacy of Cocos nucifera, Elaeis guineensis and Carapa procera oil-based repellents formulations against mosquitoes biting in Ivory Coast.

    TOXLINE Toxicology Bibliographic Information

    Konan YL; Sylla MS; Doannio JM; Traoré S

    2003-06-01

    Repellents in the form of dermal pomades are recommended as a protection against awakening and bedtime mosquito bites. If synthesis repellents are available, they are nevertheless not common and the prices remain out of reach for the communities concerned. The people therefore have to resort more and more to traditional concoctions, some of which have been shown to be effective. After demonstrating that oil-based formulations (lotions, creams, pomades) of Cocos nucifera (coconut), Elaeis guineensis (oil palm) and Carapa procera (gobi) were effective against mosquitoes, it became necessary to study the impact of the two excipients used in their manufacture, on the effectiveness of the repellents. Experiments were carried with Anopheles gambiae and Aedes aegypti under lobaratory conditions and any other mosquitoes collected under field conditions in Ivory Coast. The laboratory results indicate that the average protection times obtained with formulations with karite nut butter as excipient (54.8 +/- 37.0 mn and 74.6 +/- 26.4 mn respectively on An. gambiae and Ae. aegypti) are higher than those recorded with vaseline as excipient (respectively 42.7 +/- 30.0 mn and 60.8 +/- 33.9 mn). On the other hand, under field conditions, the biting rate percentage reduction obtained with the products with karite nut butter and vaseline excipient were similar (respectively 29.8% and 35.9% for all mosquitoes collected and 45.7% and 47.4% against An. gambiae). Nevertheless, the use of karite nut butter on repellent products should be encouraged because its sale price is very lower (10 time less) than the vaseline's.

  15. Comparison of the effect of two excipients (karite nut butter and vaseline) on the efficacy of Cocos nucifera, Elaeis guineensis and Carapa procera oil-based repellents formulations against mosquitoes biting in Ivory Coast.

    PubMed

    Konan, Y L; Sylla, M S; Doannio, J M; Traor, S

    2003-06-01

    Repellents in the form of dermal pomades are recommended as a protection against awakening and bedtime mosquito bites. If synthesis repellents are available, they are nevertheless not common and the prices remain out of reach for the communities concerned. The people therefore have to resort more and more to traditional concoctions, some of which have been shown to be effective. After demonstrating that oil-based formulations (lotions, creams, pomades) of Cocos nucifera (coconut), Elaeis guineensis (oil palm) and Carapa procera (gobi) were effective against mosquitoes, it became necessary to study the impact of the two excipients used in their manufacture, on the effectiveness of the repellents. Experiments were carried with Anopheles gambiae and Aedes aegypti under lobaratory conditions and any other mosquitoes collected under field conditions in Ivory Coast. The laboratory results indicate that the average protection times obtained with formulations with karite nut butter as excipient (54.8 +/- 37.0 mn and 74.6 +/- 26.4 mn respectively on An. gambiae and Ae. aegypti) are higher than those recorded with vaseline as excipient (respectively 42.7 +/- 30.0 mn and 60.8 +/- 33.9 mn). On the other hand, under field conditions, the biting rate percentage reduction obtained with the products with karite nut butter and vaseline excipient were similar (respectively 29.8% and 35.9% for all mosquitoes collected and 45.7% and 47.4% against An. gambiae). Nevertheless, the use of karite nut butter on repellent products should be encouraged because its sale price is very lower (10 time less) than the vaseline's. PMID:12847928

  16. The oxidation state of iron in tektite glass

    NASA Technical Reports Server (NTRS)

    Fudali, R. F.; Dyar, M. Darby; Griscom, David L.; Schreiber, Henry D.

    1987-01-01

    The reported extremes in Fe(3+)/Fe(2+) ratios of tektites are evaluated and alternative methods of analysis (wet chemical and instrumental) are explored. It is believed that most if not all Fe(3+)/Fe(2+) ratios in tektites fall within the 0.02-0.12 range. The findings suggest that tektites are not of lunar volcanic origin and that special formation conditions specific to Muong Nong tektites need not be postulated.

  17. Structure of ivory.

    PubMed

    Locke, Michael

    2008-04-01

    Profiles with all orientations have been used to visualize the 3D structure of ivory from tusks of elephant, mammoth, walrus, hippopotamus, pig (bush, boar, and warthog), sperm whale, killer whale, and narwhal. Polished, forming, fractured, aged, and stained surfaces were prepared for microscopy using epi-illumination. Tusks have a minor peripheral component, the cementum, a soft derivative of the enamel layer, and a main core of dentine=ivory. The dentine is composed of a matrix of particles 5-20 microm in diameter in a ground substance containing dentinal tubules about 5 microm in diameter with a center to center spacing of 10-20 microm. Dentinal tubules may be straight (most) or curly (pigs). The main findings relate to the way that dentinal tubules align in sheets to form microlaminae in the length of the tusk. Microlaminae are sheets of laterally aligned dentinal tubules. They are axial but may be radial (most), angled to the forming face (pigs and hippopotamus canines), or radial but helical (narwhals). Within the microlaminae the dentinal tubules may be radial, angled to the axis (whales, walrus, and pigs), or may change their orientation from one microlamina to the next in helicoids (canines of hippopotamuses, incisors of proboscidea). In the nonbanded, featureless ivories from the hippopotamus incisors, the dentinal tubules form radial microlamina from which the arrangements in other ivories can be derived. In the canines of hippopotamuses and incisors of proboscidea, the dentinal tubule orientation changes incrementally from one microlamina to the next in a helicoid, a stack of dentinal tubules that change their orientation by 180 degrees anticlockwise. Dentinal tubules having different orientations are laid down concurrently, not layer by layer as in most examples of helicoidal architecture (e.g., insect cuticle). In proboscidean ivory, the microlaminae are radial, normal to the banding of growth layers marking the plane of deposition. They form radial segments with each 180 degrees turn in the orientation of their constituent dentinal tubules. Below the cementum they are almost complete 180 degrees helicoids, but nearer to the core they become narrower with the loss of radially oriented dentinal tubules. These truncated helicoidal patterns appear in longitudinal profile as VVVV feather patterns rather than intersection intersection intersection intersection, each V or intersection being the side view of a partial or complete helicoid. The Schreger pattern in proboscidean ivory consists of these helicoids divided tangentially into columns in the length of the tusk. Narwhals have the most abundant matrix particles with their radial/helical dentinal tubules having a twist opposite to that in the cementum. PMID:18157860

  18. Mechanism of Muong Nong-type tektite formation and speculation on the source of Australasian tektites

    NASA Technical Reports Server (NTRS)

    Schnetzler, C. C.

    1992-01-01

    The source crater of the youngest and largest of the tektite strewnfields, the Australasian strewnfield, has not been located. A number of lines of evidence indicate that the Muong Nong-type tektites, primarily found in Indochina, are more primitive than the much more abundant and widespread splash-form tektites, and are proximal to the source. In this study the spatial distribution of Muong Nong-type tektite sites and chemical character have been used to indicate the approximate location of the source. The variation of Muong Nong-type tektite chemical composition appears to be caused by mixing of two silicate rock end-members and a small amount of limestone, and not by vapor fractionation. The variation in composition is not random, and does not support in situ melting or multiple impact theories. The distribution of both Muong Nong and splash-form tektite sites suggest the source is in a limited area near the southern part of the Thailand-Laos border.

  19. Constraints on the formation of layered tektites from the excavation and analysis of layered tektites from northeast Thailand

    NASA Astrophysics Data System (ADS)

    Fiske, Peter S.

    1996-01-01

    The size, shape, composition, and vesicle content of 6 kg of layered tektite fragments, excavated near the town of Huai Sai, Thailand, place some constraints on the formation of layered tektites. The mass, shape, and distribution of the fragments are not consistent with an origin as a "puddle" of impact melt but suggest that they were derived from a single equant block. The presence of vesicles up to 7 mm in mean diameter within the tektite fragments suggests that the material was too viscous to allow for significant gravity-driven flow. These results suggest that layered tektites may be analogous to lava bombs, which may have been stretched and deformed in flight but underwent little flow after landing. Rather than being a product of "unusual circumstances," such as multiple impacts, layered tektites may differ from splash-form tektites only in initial temperature of formation, speed of ejection, and small differences in initial composition.

  20. Study of the ablative effects on tektites: Atmosphere entry of a swarm of tektites. [shielding by hypersonic wake

    NASA Technical Reports Server (NTRS)

    Sepri, P.; Chen, K. K.

    1977-01-01

    The large variety of ablation markings observed on recovered tektites lead to the previously proposed swarm wake model which states that the lead peripheral tektites bore the blunt of aerodynamic heating upon entry, and that the bulk of tektites in the wake enjoyed partial shielding at the expense of the leaders. Further considerations are presented in support of this model. Quantitative assessments indicate that wake shielding might indeed have provided for substantially less heating than would have been experienced by a tektite entering an undisturbed atmosphere along a similar trajectory. For the case of strong wake shielding it is even possible that the surface temperature of a falling tektite had barely reached its melting point. In the distribution of tektites, there is a size band (near R = 0.5 cm) which is least susceptible to melting.

  1. Volatile fractionation and tektite source material

    NASA Technical Reports Server (NTRS)

    Walter, Louis S.

    1989-01-01

    The arguments used by Love and Woronow (1988) to assess the role played in the origin of bediasites by extensive volatile fractionation are critically examined. Using the ratios of 'refractory' oxides, CaO, Al2O3, and MgO, to the 'volatile' oxides, Na2O and K2O, these authors concluded that vapor fractionation did not play a significant role. In this paper, experimental evidence is presented that shows that the assumption of volatility for the alkali elements (as least with respect to silica) to be not valid under the conditions under which tektites formed. It is shown that the results of vapor fractionation in experiments on glasses of tektite composition are approximately parallel the trends seen in bediasite analysis.

  2. Tektites - Volcanic ejecta from the moon

    NASA Technical Reports Server (NTRS)

    Cameron, W. S.; Lowrey, B. E.

    1975-01-01

    The possibility is considered that tektites are lunar volcanic ejecta, and lunar regions are examined from which tektites could be ejected with the necessary velocities and trajectories to reach the earth. The examined regions include areas around the Lunar Transient Phenomena sites near Censorinus, Messier, Messier A, and Taruntius, the area of Mare Foecunditatis near Secchi X, areas near Cauchy and Capella, and the eastern part of Mare Tranquillitatis. Evidence of acidic volcanic activity in these regions is described in detail, including possible calderas, mudflows, and endogenous domes. It is suggested that the moon is still gently degassing and that more violent eruptions of material may still occur on rare occasions. Remotely-sensed evidence of recent lunar internal activity is noted.

  3. Origin of tektites: an alternative to terrestrial impact theory.

    PubMed

    Izokh, E P

    1996-01-01

    The Terrestrial Impact Theory (TIT) has won a complete victory over O'Keefe's lunar volcanic theory, but only because the Moon appears to be the wrong place for tektites. Indeed, the TIT ignores strong evidence of their volcanic origin--far from the Moon. The Extraterrestrial Volcanic Comet Theory proposes an alternative to both of these theories. Major arguments for an extraterrestrial tektite source are paradoxical: a great time difference between tektite formation and their arrival on Earth, and also forms, plastic deformations, ice collision marks, vacuum voids, etc. indicating specific conditions of tektite formation such as low gravitational field, lack of atmosphere, interaction of hot plastic tektites with ice, etc. Major evidence of volcanic origin includes: close analogy between shaped tektites and small volcanic bombs, and between layered tektites and lava or tuff-lava flows or huge bombs; analogy between flanged tektites and volcanic bombs ablated by gasjets: long-time, multistage formation of some tektites that corresponds to wide variations in their radiometric ages; well-ordered long compositional trends (series) typical of magmatic differentiation; different compositional tektite families (subseries) comparable to different stages (phases) of the volcanic process. Thus, different types of volcanic eruptions under extraterrestrial conditions could be reconstructed based on tektite properties. It is presumed that tektites were transported to the Earth by specific eruptive comets, i.e. in the form of ice-tektite agglomerates launched into space by volcanic explosion. Major arguments favouring comets include: ice collision marks and imprints as mentioned above; linear band-like sculpture of the Australasian strewn field as evidence of comet fragmentation and slope or skipping trajectory of separate fragments; compact coincidence of the Zhamanshin impact crater with small tektite strewn field as evidence of steep trajectory of separate comet fragments that disintegrated while entering the atmosphere. The comet-Earth collision under consideration happened 10,000 years ago and caused the global catastrophe marked by the sharp Pleistocene-Holocene boundary, i.e. by abrupt climatic changes, the end of glaciation, mass extinction, etc. This event can be compared with the "dinosaur" catastrophe at the K/T boundary 65 Ma, which was also accompanied by tektite fall. PMID:11541098

  4. [The spectrum characteristic analysis of mammoth ivory].

    PubMed

    Yin, Zuo-wei; Luo, Qin-feng; Zheng, Chen; Bao, De-qing; Li, Xiao-lu; Li, Yu-ling; Chen, Quan-li

    2013-09-01

    Due to the similarities between mammoth ivory ornaments and modern elephant ivory ones in the market, the spectral properties of the two kinds of ivories were analyzed and compared in the present paper through the gemological tests, infrared spectrum and X-ray powder diffraction, etc. The research found that the refractive index and specific gravity of the two ivories are very similar. The refractive index of mammoth ivory is 1.52-1.53 whereas that of elephant ivory is 1.54-1.55. The specific gravity of mammoth ivory is 1.77 and that of elephant ivory is 1.72. It should be careful that Schreger angles are used to distinguish the two kinds of ivories, because the angles of inner and middle layers in the two kinds of tusks are similar except the angles of elephant tusk out-layers are larger than those of mammoth (The Schreger angle of the sample mammoth ivory belonging to out-layer tusks is 100 degrees nd that of elephant ivory is 115 degrees). In addition, the out-layer Schreger angles of Asian elephants are normally less than 120 degrees, while those of Africa elephants are bigger than 120 degrees (This can be used to identify Asian and Africa elephant ivories). The infrared spectroscopy test shows that the water-molecule-related absorption peaks of 3319, 1642 and 1557 cm(-1) are more obvious in the modern elephant ivory samples than in the mammoth ivory samples; the collagen-related absorption peaks of 2927and 2855 cm(-1) are obvious in the modern elephant ivory but extremely weak in the mammoth ivory. The results indicate that collagen and crystallized water in mammoth ivory reduced to a very low level after having been buried for a long period. X-ray powder diffraction results show that the diffraction peak splits of mammoth ivories are more obvious and sharp than that of elephant ivories, which means hydroxyapatites crystallized better despite being buried for thousands of years. Hence, it is an important reference for identifying the two kinds of ivories that the ivory organic matter was losing and inorganic matter crystallized better at same time after having been buried. PMID:24369627

  5. A 10.8-kg layered (Muong-Nong-type) tektite from Wenchang, Hainan, China

    NASA Technical Reports Server (NTRS)

    Futrell, Darryl S.; Wasson, John T.

    1993-01-01

    A 10.79-kg layered tektite from Hainan is the largest tektite from China, and the fifth largest reported to date. It, together with a 1.9-kg Hainan tektite described by Yuan (1981), greatly extends the area of the Australasian field within which layered tektites having masses greater than 1 kg have been found.

  6. Field recovery of layered tektites in northeast Thailand

    SciTech Connect

    Wasson, J.T.; Pitakpaivan, K.; Putthapiban, P.

    1995-07-25

    The authors recovered Australasian tektites in place throughout a 40 X 130 km region in northeast Thailand extending from the Laotian border westward to a line connecting Na Pho Klang in the northeast through Det Udom to Nam Yun in the south. With two exceptions, in sites near the western edge of this region, all fragments are layered (muong-Nong-type) tektites. It appears that large layered tektites are mainly found by rice farmers in fields that were forested until the recent past. The presence of layered tektites in this 40 X 130 km area implies that impact melt that fell in these areas was hot enough to flow if it was deposited on a sloping surface. The absence of splash-form tektites from the region indicates that the layer was still molten when masses having shapes (teardrops, dumbbells, etc.) produced by spinning reached the ground. To account for this and to allow time for the melt to flow a few tens of centimeters requires that the atmosphere remained hot (>2300 K) for a few minutes. Tektites that are in place are almost always associated with a widespread 10-cm to meter-thick layer of laterite. In two cases (one involving layered, one involving splash-form tektites), where accurate stratigraphic control demonstrated that the tektites were still in section, they were sited on top of the laterite layer just below a layer of aeolian sand. 27 refs., 1 fig., 1 tab.

  7. Tektite-like bodies at Lonar Crater, India - Implications for the origin of tektites

    NASA Technical Reports Server (NTRS)

    Murali, A. V.; Zolensky, M. E.; Blanchard, D. P.

    1987-01-01

    Homogeneous dense glass bodies (both irregular and splash form) with high silica contents (about 67 pct SiO2) occur in the vicinity of Lonar Crater, India. Their lack of microlites and mineral remnants and their uniform chemical composition virtually preclude a volcanic origin. They are similar to tektites reported in the literature. While such a close association of tektite-like bodies with impact craters is already known (Aouelloul Crater, Mauritania; Zhamanshin Crater, U.S.S.R.), the tektite-like bodies at Lonar Crater are unique in that they occur in an essentially basaltic terrain. Present geochemical data are consistent with these high silica glass bodies being impact melt products of two-thirds basalt and one-third local intertrappean sediment (chert). The tektite-like bodies of the impact craters Lonar, Zhamanshin, and Aouelloul are generally similar. Strong terrestrial geochemical signatures reflect the target rock REE patterns and abundance ratios and demonstrate their terrestrial origin resulting from meteorite impact, as has been suggested by earlier workers.

  8. Annual Movement Patterns of Endangered Ivory Gulls: The Importance of Sea Ice

    PubMed Central

    Spencer, Nora C.; Gilchrist, H. Grant; Mallory, Mark L.

    2014-01-01

    The ivory gull (Pagophila eburnea) is an endangered seabird that spends its entire year in the Arctic environment. In the past three decades, threats from various sources have contributed to a >70% decline in Canada. To assess the annual habitat needs of this species, we attached satellite transmitters to 12 ivory gulls on Seymour Island, Nunavut in 2010, which provided up to four breeding seasons of tracking data. Analysis of migratory behaviour revealed considerable individual variation of post-breeding migratory route selection. Ivory gulls traveled a median of 74 days during post-breeding migration, but only 18 days during pre-breeding migration. In contrast to predictions, ivory gulls did not use the Greenland coast during migratory periods. Ivory gulls overwintered near the ice edge in Davis Strait, but also used the Labrador Sea in late February and March. We suggest that the timing of formation and recession and extent of sea ice plays a large role in ivory gull distribution and migratory timing. PMID:25551556

  9. A New Tektite Discovery in the Guangdong Province, China, and the Search for the Source Crater of the Australasian Tektite Strewn Field

    NASA Astrophysics Data System (ADS)

    Kenkmann, T.; Maier, R. V.; Sturm, S.; Zhu, Meng-Hua.

    2014-09-01

    A new tektite location in South China is presented that belongs to the Australasian tektite strewnfield. We also investigated a 30 km circular structure in the Guangdong and Guangxi Province that might be related to the Australasian impact event.

  10. Viscous flow and crystallization behavior of tektite glasses

    NASA Technical Reports Server (NTRS)

    Klein, L. C.; Yinnon, H.; Uhlmann, D. R.

    1980-01-01

    The variation of viscosity with temperature was determined in the 200-2000 K range for a Muong Nong tektite material. The viscosity at the liquidus temperature of 1320 C is 20,000 P; treatments between 900 and 1300 C do not result in significant crystallization in the natural sample except when the sample is heated in contact with a synthetic tektite composition. Two synthetic microtektite with lower SiO2 contents than the Muong Nong material were also examined; heat flow calculations were performed for 2.5 to 10 cm spheres of tektite when cooling by radiation.

  11. 3-D laser images of splash-form tektites and their use in aerodynamic numerical simulations of tektite formation

    NASA Astrophysics Data System (ADS)

    Samson, C.; Butler, S.; Fry, C.; McCausland, P. J. A.; Herd, R. K.; Sharomi, O.; Spiteri, R. J.; Ralchenko, M.

    2014-05-01

    Ten splash-form tektites from the Australasian strewn field, with masses ranging from 21.20 to 175.00 g and exhibiting a variety of shapes (teardrop, ellipsoid, dumbbell, disk), have been imaged using a high-resolution laser digitizer. Despite challenges due to the samples' rounded shapes and pitted surfaces, the images were combined to create 3-D tektite models, which captured surface features with a high fidelity (?30 voxel mm-2) and from which volume could be measured noninvasively. The laser-derived density for the tektites averaged 2.41 0.11 g cm-3. Corresponding densities obtained via the Archimedean bead method averaged 2.36 0.05 g cm-3. In addition to their curational value, the 3-D models can be used to calculate the tektites' moments of inertia and rotation periods while in flight, as a probe of their formation environment. Typical tektite rotation periods are estimated to be on the order of 1 s. Numerical simulations of air flow around the models at Reynolds numbers ranging from 1 to 106 suggest that the relative velocity of the tektites with respect to the air must have been <10 m s-1 during viscous deformation. This low relative velocity is consistent with tektite material being carried along by expanding gases in the early time following the impact.

  12. The problem of the origin of tektites from Zhamanshin astrobleme

    NASA Astrophysics Data System (ADS)

    Takhauov, Artur; Anoshin, Dmitriy; Plotnikova, Irina

    2013-04-01

    Tektites (from Greek. Tekts - molten, melted) - are natural glassy formations of yellow, green, but mostly black color, completely fused, that may have different shape and size. According to their composition tektites are high-silicon (acidic) glasses. The content of SiO may reach 88,5%, AlO - 20,5%, FeO - 11,5%, and CaO - 8,5%. The presence of Ni and relatively low content of water in comparison with other glasses (only 0.02%, which is 10 times less than in the volcanic glass) is of particular importance. The name to tektites was given by Austrian geologist E. Suess (1900). Tektites are often denominated according to their location: irgizites and zhamanshinites (river Irgiz and Zhamanshin hole in Kazakhstan), moldavites [river Moldava (modern Vltava, Czech Republic)] filippinites (Philippines), idoshinites (Indo-china), avstralites (Australia), etc. There is still no generally accepted hypothesis about the origin of tektites: some consider them to be a part of meteorites, others suggest that tektites are the result of the explosion and melting of terrestrial matter that happens when meteorites, asteroids or comets fall down on Earth. The aim of the present work is to conduct analytic studies of tektites from Zhamanshin crater. We examined 50 samples that are part of the collection from the Zhamanshin crater gathered in 1979 by I.N. Plotnikova during her student field expedition led by P.V. Florenskiy. For the convenience of the research of tektites during its early stages the authors compiled a morphological classification of the given samples. On the basis of the visual inspection by the help of a magnifying glass we distinguished the following groups of tektites, which are characterized by certain morphological features: 1. Porous (cavernous), black, isometric shape 2. Porous (cavernous), yellowish-brown, isometric shape 3. Elongated, torose 4. Elongated, with glassy luster 5. Elongated, twisted 6. worm-shaped 7. Vitreous, glassy 8. Deformated The vast majority of researchers believe that the surface of tektites reflects the dynamic resistance of the medium (air) that they were experiencing in their movement. Visual examination of the samples confirms that, and looking at the most tektites, it is difficult not to agree with this idea. Consequently, we can make an assumption that the morphology of tektites depends on the conditions of the genesis (in particular, on the distance and the expansion velocity of tektites). Aubrey Whymark, a famous contemporary specialist in tektites, also believes that the morphology is associated with the range of expansion of tektites from an impact crater, which, according to his theory, are formed as a result of impact metamorphism. This opinion is shared by many scientists involved in the research of tektites. In the next phase of the research the samples of all the morphological groups were examined using electron microscopy. During this analysis, we have found non-melted areas of the rock in 3 out of 50 samples (these were the rocks of the 2nd and the 7th groups from our classification). We also detected the features of the surface patterns that testify the impact formation of tektites.

  13. Jetting and the origin of tektites

    NASA Technical Reports Server (NTRS)

    Vickery, A. M.

    1991-01-01

    The scientific consensus is that tektites were produced by impacts on the Earth, but the exact mechanism by impacts might form tektites is still unclear. The most widely cited mechanism is jetting, which results from the extremely high pressures generated at the intersection of two bodies whose surfaces converge obliquely at high speed. Theory of jetting for thin plates is extended to the case of the impact of the sphere onto a half-space. The calculations are done for the impact of a silicate sphere onto a silicate target for impact speeds of 15, 20, and 25 km/sec, spanning the range of reasonable impact speeds for asteroids. The angle of impact is varied from 0 to 75 deg. The mass jetted, the jet velocity, projectile fraction in the jet, azimuthal distribution of the jet, and the phase of the jetted material are calculated as functions of time. The total mass jetted and the overall mass-averages of jet velocity, etc. are also calculated.

  14. Diminished tektite ablation in the wake of a swarm

    NASA Technical Reports Server (NTRS)

    Sepri, P.; Chen, K. K.; Okeefe, J. A.

    1981-01-01

    Observations of ablation markings on tektite surfaces reveal that a large variation in aerodynamic heating must have occurred among the members of a swarm during atmospheric entry. In a few cases, the existence of jagged features indicates that these tektite surfaces may have barely reached the melting temperature. Such an observation seems to be incompatible with the necessarily large heating rates suffered by other tektites which exhibit the ring wave melt flow. A reconciliation is proposed in the form of a wake shielding model which is a natural consequence of swarm entry. Calculations indicate that the observed ablation variations are actually possible for swarm entry at greater than escape velocity. This aerodynamic conclusion provides support for the arguments favoring extraterrestrial origin of tektites.

  15. Study of the ablative effects on tektite. [reentry trajectories

    NASA Technical Reports Server (NTRS)

    Chen, K. K.

    1975-01-01

    The tumbling and surface roughness effects on the trajectory of entry tektite were studied in both free molecular and continuum flows. It is shown that, while surface roughness has negligible effect on trajectory, the tumbling may play an important role in tektite trajectory and the consequent ablation, provided the body shape is different from a sphere. A shape factor B was proposed to measure the shape irregularity and is found to be a good parameter for correlations between body shape and tumbling effects.

  16. The oxidation state of iron in tektite glass

    SciTech Connect

    Fudali, R.F. ); Dyar, M.D. ); Griscom, D.L. ); Schreiber, H.D. )

    1987-10-01

    Fe{sup 3+}/Fe{sup 2+} ratios in tektite glass have the potential for constraining the f{sub O{sub 2}}-T conditions associated with tektite melts prior to quenching. But even discounting older analyses, values of Fe{sup 3+}/Fe{sup 2+} in the literature range from zero to 0.82. The authors have analyzed five tektites from populations that have been reported to have Fe{sup 3+}/Fe{sup 2+} ratios both of zero and also a range of ratios up to 0.67. The authors employed several wet chemical techniques and two instrumental techniques - Moessbauer and Electron Spin Resonance - for all five samples and failed to confirm either extreme. The range they found of 0.02-0.12 is in excellent agreement with the literature values that they consider to be consistently most reliable and they believe that most if not all Fe{sup 3+}/Fe{sup 2+} ratios in tektites fall within this range. The obvious presence of systematic errors in their data set strongly suggests the true range is narrower than their reported range. Additional standardization work is need to address these systematic errors. Nevertheless, the authors present accuracy is sufficient to demonstrate that there is no need to invoke a lunar volcanic origin for tektites or to postulate special formation conditions specific to Muong Nong tektites.

  17. Healdsburgite - a New Tektite and Associated Tektite Strewnfield in North Central California

    NASA Astrophysics Data System (ADS)

    Erickson, R. C.; Deino, A. L.; Norwick, S. A.; Byrd, C.

    2012-12-01

    Erickson, Rolfe; Norwick, Steven; and Byrd, Caitlin, Sonoma State University; Deino, Alan, Berkeley Geochronology Center. I A Distinctive Glass Clast Population In numerous locations in Sonoma and Solano Counties in north central California, over an area of ~ 200 km2, distinctive ~ 1-5 cm dominantly ovoid glass clasts are found as part of the pebble population in young sediments. They are composed of black massive aphyric nonvesicular glass whose surfaces are totally covered with a texture of adjoining small deep pits and grooves. The pits are hemispherical, 1-10 mm across, and join at sharp edges composed of straight segments. The grooves, where present, are the width and depth of the pits and may be up to several cm long and vermicular. Some clasts have internal layering resembling flow textures. These glass objects were brought to our attention by a local resident, Ms. Diane Moore, about 20 years ago. Four of these glass clasts from widely separated locations in the exposure area have been dated by the laser incremental-heating Ar39/Ar40 method at the Berkeley Geochronology Center, with an age of ~ 2.81 Ma (upper Pliocene). The four samples have mutually overlapping ages at one sigma. Chemical analyses of the 10 major and 50 minor elements, of four widely separated clasts, were obtained at commercial laboratories. The clasts are all rhyolites and cluster tightly on the TAS diagram of Le Maitre et al (2002). All available data show that all these pitted and grooved clasts are part of a single population. II. The Clasts are Tektites We believe these distinctive glass clasts to be tektites for the following reasons: 1. Pits are always present and wholly cover the clast surface. Perhaps half the clasts also have distinctive irregular vermicular grooves superimposed on the pitted surface. This surface pattern is like those on other long-recognized 'classic' tektites, like indochinites. The clasts look like tektites; compare McCall (2001, Figure 2.30) for example. 2. The clasts show no significant weathering. Once cleaned of adhering sediment, they are solid and vitreous. There are also no cases of partial development of the distinctive surface texture, as might be expected if it were a consequence of in situ weathering. 3. The clasts do not have a detrital origin; they are not obsidian pebbles. The pit and groove pattern, which is uniformly well developed on clasts throughout the distribution area, is fragile and could not have survived much transport. 4. The clasts are not volcanic in origin (i.e., 'apache tears'). The pit and groove pattern contrasts with the relatively smooth surface of apache tears, and the clasts bear no resemblance to lapilli. Their distinctive appearance and uniform age and chemistry suggests that these objects are tektites in a strewnfield, only a small part of which has been identified to date. No related impact site has been identified, but clast composition suggests a continental target. We suggest these clasts, heretofore informally called Healdsburg glass, be recognized as tektites and called healdsburgites, in the manner of other tektites. A public domain PDF format copy of this poster will be available for download in the digital archive in the Sonoma State University library.

  18. Seconds After Impact: Insights from Diffusion Between Lechatelierite and Host Glass in Tektites and Experiments

    NASA Astrophysics Data System (ADS)

    Macris, C. A.; Badro, J.; Asimow, P. D.; Eiler, J. M.; Stolper, E. D.

    2014-09-01

    This study exploits the presence of lechatelierites in tektites to extract information about their thermal histories by investigating chemical diffusion between molten silica inclusions and surrounding felsic melt in natural tektites and experiments.

  19. New estimates of area and mass for the North American tektite strewn field

    NASA Technical Reports Server (NTRS)

    Koeberl, C.

    1989-01-01

    A revised estimate is given for the total mass of the North American tektite material, which is based on a concept of patches or rays of distribution rather than on a continuous tektite and microtektite blanket. This concept yields a total mass of about 3 x 10 to the 14th g, which is less than a third of previous estimates. The shape of the North American tektite strewn field is in agreement with other tektite strewn fields.

  20. Optical magnetic, and electrical properties of tektites, meteorites, and other space related materials

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The scope of the project is reported to study the infrared absorption of water and the magnetic properties of the iron in tektites. Subsequently, the work was expanded to include the other properties of tektites and lunar materials. When the lunar samples became available, the emphasis of the research shifted from tektites to lunar samples.

  1. Source of Australasian tektites: Investigating possible impact sites in Laos

    NASA Astrophysics Data System (ADS)

    Schnetzler, C. C.; McHone, J. F.

    1996-01-01

    The site of an impact event that spread ejecta in the form of tektites and microtektites over 5 107 km2 of the southern Pacific and Indian Ocean area has not yet been discovered. A number of lines of evidence point toward a source in eastern Indochina. From an examination of a digital topographic data set and Landsat imagery, we identified four candidate structures in southern Laos, and we visited these sites in 1995 February. No evidence of impact origin of these structures could be found; flat-lying, undisturbed Mesozoic sedimentary rocks similar to those on Thailand's Khorat Plateau were found over the region. Small layered tektite fragments are relatively common in a lateritic horizon that is characterized by the presence of quartz pebbles. This scene is identical to the situation found several hundred kilometers to the southeast in Thailand. New tektite sites identified on this trip support a previous suggestion that there is a large region in southern NE Thailand and Laos that is rich in Muong Nong-type (layered) tektites but seemingly devoid of the splash-form type tektites.

  2. Magnetic susceptibility of tektites and some other glasses

    USGS Publications Warehouse

    Senftle, F.E.; Thorpe, A.

    1959-01-01

    The magnetic susceptibility at several magnetic field strengths of about thirty tektites from various localities have been measured. The susceptibility ranges from 2 ?? 10-6 to about 7.9 ?? 10-6 e.m.u./g. Tektites from a given locality have similar susceptibilities. The intensity of magnetization of all the tektites measured is zero or very small. For comparison, the same measurements have been made on about thirty obsidians. The magnetic susceptibilities cover approximately the same range, but the intensity of magnetization of the impurity was found to be much higher. By heating the obsidians to 1450??C the intensity of magnetization was reduced to zero. From the above data, it is shown that the tektites must have been heated well above 1400??C, and that essentially all the iron is in solution. On the other hand, the evidence shows that obsidians have not been heated much above this temperature, and that there is a significant amount of undissolved iron in the glass, probably as magnetite. Further, if tektites are extraterrestrial, they probably entered the earth's atmosphere as a glass. ?? 1959.

  3. The water, deuterium, gas and uranium content of tektites

    USGS Publications Warehouse

    Friedman, I.

    1958-01-01

    The water content, deuterium concentration of the water, total gas and uranium contents were determined on tektite samples and other glass samples from Texas, Australia, Philippine Islands, Java, French Indo-China, Czechoslovakia, Libyan Desert, Billiton Island, Thailand, French West Africa, Peru, and New Mexico. The water content ranges from 0.24 per cent for the Peru tektite, to 0.0002 per cent for a moldavite. The majority of the tektites have less than 0.05 per cent water, and average 0.005 per cent H2O by weight. No other gases were detected, the lower detection limit being about 1 p.p.m. by weight. The deuterium content of the water in tektites is in the same range as that in terrestrial waters, and varies from 0.010 mole per cent to 0.0166 mole per cent deuterium. The uranium content is about from 1 to 3 p.p.m. The possible origin of tektites is discussed. The experimental data presented favour their being originally terrestrial, but produced by some catastrophic event. An extra-terrestrial source is not ruled out. ?? 1958.

  4. Beryllium-10 in Australasian tektites - Evidence for a sedimentary precursor

    NASA Technical Reports Server (NTRS)

    Pal, D. K.; Moniot, R. K.; Kruse, T. H.; Herzog, G. F.; Tuniz, C.

    1982-01-01

    Each of seven Australasian tektites contains about 100 micron atoms of beryllium-10 (half-life, 1.53 million years) per gram. Cosmic-ray bombardment of the australites cannot have produced the measured amounts of beryllium-10 either at the earth's surface or in space. The beryllium-10 contents of these australites are consistent with a sedimentary precursor that adsorbed from precipitation beryllium-10 produced in the atmosphere. The sediments must have spent several thousand years at the earth's surface within a few million years of the tektite-producing event.

  5. Beryllium-10 in australasian tektites: evidence for a sedimentary precursor.

    PubMed

    Pal, D K; Tuniz, C; Moniot, R K; Kruse, T H; Herzog, G F

    1982-11-19

    Each of seven Australasian tektites contains about 1 x l0(8) atoms of beryllium-10 (half-life, 1.53 x 10(6) years) per gram. Cosmic-ray bombardment of the australites cannot have produced the measured amounts of beryllium-10 either at the earth's surface or in space. The beryllium-10 contents of these australites are consistent with a sedimentary precursor that adsorbed from precipitation beryllium-10 produced in the atmosphere. The sediments must have spent several thousand years at the earth's surface within a few million years of the tektite-producing event. PMID:17771035

  6. A possible tektite strewn field in the Argentinian Pampa.

    PubMed

    Bland, P A; de Souza Filho, C R; Jull, A J T; Kelley, S P; Hough, R M; Artemieva, N A; Pierazzo, E; Coniglio, J; Pinotti, L; Evers, V; Kearsley, A T

    2002-05-10

    Impact glass associated with 11 elongate depressions in the Pampean Plain of Argentina, north of the city of Rio Cuarto, was suggested to be proximal ejecta related to a highly oblique impact event. We have identified about 400 additional elongate features in the area that indicate an aeolian, rather than an impact, origin. We have also dated fragments of glass found at the Rio Cuarto depressions; the age is similar to that of glass recovered 800 kilometers to the southeast. This material may be tektite glass from an impact event around 0.48 million years ago, representing a new tektite strewn field. PMID:12004127

  7. Beryllium-10 in Australasian tektites: evidence for a sedimentary precursor

    SciTech Connect

    Pal, D.K.; Tuniz, C.; Moniot, R.K.; Kruse, T.H.; Herzog, G.F.

    1982-11-19

    Each of seven Australasian tektites contains about 1 x 10/sup 8/ atoms of beryllium-10 (half-life, 1.53 x 10/sup 6/ years) per gram. Cosmic-ray bombardment of the australites cannot have produced the measured amounts of beryllium-10 either at the earth's surface or in space. The beryllium-10 contents of these australites are consistent with a sedimentary precursor that adsorbed from precipitation beryllium-10 produced in the atmosphere. The sediments must have spent several thousand years at the earth's surface within a few million years of the tektite-producing event.

  8. Metallic spherules in tektites from Isabela, Philippine Islands

    USGS Publications Warehouse

    Chao, E.C.T.; Adler, I.; Dwornik, E.J.; Littler, J.

    1962-01-01

    Iron-nickel spherules, as much as 0.5 mm in diameter, have been found completely embedded in some philippinites. The spherules consist mainly of kamacite with unidentified pink inclusions. The meteoritic origin of these spherules seems reasonable, suggesting that the tektites containing them were formed by asteroidal or meteoritic impact.

  9. Magnetic properties of tektites and other related impact glasses

    NASA Astrophysics Data System (ADS)

    Rochette, P.; Gattacceca, J.; Devouard, B.; Moustard, F.; Bezaeva, N. S.; Cournède, C.; Scaillet, B.

    2015-12-01

    We present a comprehensive overview of the magnetic properties of the four known tektite fields and related fully melted impact glasses (Aouelloul, Belize, Darwin, Libyan desert and Wabar glasses, irghizites, and atacamaites), namely magnetic susceptibility and hysteresis properties as well as properties dependent on magnetic grain-size. Tektites appear to be characterized by pure Fe2+ paramagnetism, with ferromagnetic traces below 1 ppm. The different tektite fields yield mostly non-overlapping narrow susceptibility ranges. Belize and Darwin glasses share similar characteristics. On the other hand the other studied glasses have wider susceptibility ranges, with median close to paramagnetism (Fe2+ and Fe3+) but with a high-susceptibility population bearing variable amounts of magnetite. This signs a fundamental difference between tektites (plus Belize and Darwin glasses) and other studied glasses in terms of oxygen fugacity and heterogeneity during formation, thus bringing new light to the formation processes of these materials. It also appears that selecting the most magnetic glass samples allows to find impactor-rich material, opening new perspectives to identify the type of impactor responsible for the glass generation.

  10. Soret diffusion: A possible cause of compositional heterogeneity within tektites

    NASA Technical Reports Server (NTRS)

    Delano, J. W.; Liu, Y.-G.; Schmitt, R. A.

    1993-01-01

    Although a terrestrial origin for tektites is well-established on geochemical evidence, the physical processes involved in tektite formation have been largely ignored by geochemists and petrologists. For example, two observations that potentially bear on the physics of their origin are the following: (1) The flange of an australite is often more heterogeneous than its core; and (2) microtektites are compositionally more diverse than tektites. The first observation contradicts the traditional view of flange formation since a second heating to super-liquidus temperatures during atmospheric re-entry should, by chemical diffusion and mixing, have tended to homogenize the melt as it flowed off the leading edge of the core to form the flange. Analyses of an australite flange have been performed by electron microprobe. The results of those analyses emphasize the magnitude of the heterogeneity, as well as the well-defined elemental correlations that may constrain the process responsible for it. The second observation that the bulk compositions of microtektites are more divers than the tektites within the same strewnfield is a well-known characteristic, for which no quantitative explanation has been offered. The current investigation has involved the analysis of 43 Australasian microtektites from the Wharton Basin by electron microprobe, as well as trace-element abundances on fifteen of these microtecktites by INAA.

  11. Dissecting the illegal ivory trade: an analysis of ivory seizures data.

    PubMed

    Underwood, Fiona M; Burn, Robert W; Milliken, Tom

    2013-01-01

    Reliable evidence of trends in the illegal ivory trade is important for informing decision making for elephants but it is difficult to obtain due to the covert nature of the trade. The Elephant Trade Information System, a global database of reported seizures of illegal ivory, holds the only extensive information on illicit trade available. However inherent biases in seizure data make it difficult to infer trends; countries differ in their ability to make and report seizures and these differences cannot be directly measured. We developed a new modelling framework to provide quantitative evidence on trends in the illegal ivory trade from seizures data. The framework used Bayesian hierarchical latent variable models to reduce bias in seizures data by identifying proxy variables that describe the variability in seizure and reporting rates between countries and over time. Models produced bias-adjusted smoothed estimates of relative trends in illegal ivory activity for raw and worked ivory in three weight classes. Activity is represented by two indicators describing the number of illegal ivory transactions--Transactions Index--and the total weight of illegal ivory transactions--Weights Index--at global, regional or national levels. Globally, activity was found to be rapidly increasing and at its highest level for 16 years, more than doubling from 2007 to 2011 and tripling from 1998 to 2011. Over 70% of the Transactions Index is from shipments of worked ivory weighing less than 10 kg and the rapid increase since 2007 is mainly due to increased consumption in China. Over 70% of the Weights Index is from shipments of raw ivory weighing at least 100 kg mainly moving from Central and East Africa to Southeast and East Asia. The results tie together recent findings on trends in poaching rates, declining populations and consumption and provide detailed evidence to inform international decision making on elephants. PMID:24250744

  12. Dissecting the Illegal Ivory Trade: An Analysis of Ivory Seizures Data

    PubMed Central

    Underwood, Fiona M.; Burn, Robert W.; Milliken, Tom

    2013-01-01

    Reliable evidence of trends in the illegal ivory trade is important for informing decision making for elephants but it is difficult to obtain due to the covert nature of the trade. The Elephant Trade Information System, a global database of reported seizures of illegal ivory, holds the only extensive information on illicit trade available. However inherent biases in seizure data make it difficult to infer trends; countries differ in their ability to make and report seizures and these differences cannot be directly measured. We developed a new modelling framework to provide quantitative evidence on trends in the illegal ivory trade from seizures data. The framework used Bayesian hierarchical latent variable models to reduce bias in seizures data by identifying proxy variables that describe the variability in seizure and reporting rates between countries and over time. Models produced bias-adjusted smoothed estimates of relative trends in illegal ivory activity for raw and worked ivory in three weight classes. Activity is represented by two indicators describing the number of illegal ivory transactions – Transactions Index – and the total weight of illegal ivory transactions – Weights Index – at global, regional or national levels. Globally, activity was found to be rapidly increasing and at its highest level for 16 years, more than doubling from 2007 to 2011 and tripling from 1998 to 2011. Over 70% of the Transactions Index is from shipments of worked ivory weighing less than 10 kg and the rapid increase since 2007 is mainly due to increased consumption in China. Over 70% of the Weights Index is from shipments of raw ivory weighing at least 100 kg mainly moving from Central and East Africa to Southeast and East Asia. The results tie together recent findings on trends in poaching rates, declining populations and consumption and provide detailed evidence to inform international decision making on elephants. PMID:24250744

  13. Vector diagram of the chemical compositions of tektites and earth lavas

    NASA Technical Reports Server (NTRS)

    Kvasha, L. G.; Gorshkov, G. S.

    1978-01-01

    The chemical compositions of tektites and various volcanic glasses, similar in composition to tektites are compared by a petrochemical method. The advantage of the method is that a large number of chemical analyses of igneous rocks can be graphically compared with the help of vectors, plotted in relation to six parameters. These parameters, calculated from ratios of the main oxides given by silicate analysis, reflect the chief characteristics of igneous rock. Material for the study was suppled by data from chemical analysis characterizing tektites of all known locations and data from chemical analyses of obsidians similar in chemical composition to tektites of various petrographical provinces.

  14. Zircon and chromite crystals in a muong nong-type tektite.

    PubMed

    Glass, B P

    1970-08-21

    Chromite, zircon, and quartz crystals (identified by x-ray diffraction) have been recovered from a 2.07-gram sample of Muong Nong-type tektite. The absence of eskolaite (Cr(2)O(3)) and baddeleyite (ZrO(2)) supports a previous conclusion that Muong Nong-type tektites were not heated as intensely as other tektite groups. X-ray asterism studies indicate that the crystals are shocked, which supports an impact origin. The presence of chromite and zircon together suggests that the Muong Nong-type tektite was produced from sedimentary material. PMID:17820307

  15. Taking the Plunge off the Ivory Tower.

    ERIC Educational Resources Information Center

    Mauzerall, Jorgette

    1997-01-01

    Relates the experiences of a white academic teaching in a black rural state college--a plunge into the world of black experience which shocked the academic. States that everything was different--students' names, their manner of dress, their reaction to the O.J. Simpson verdict. Finds that leaving the ivory tower was not easy, but the job exceeded

  16. Post-Primary Options in the Ivory Coast.

    ERIC Educational Resources Information Center

    Daniere, Andre; Orivel, Francois

    Designed to provide information for decision-making by Ivorian authorities in the planning of post-primary education over the coming decade, this study compares the implications of alternative policies or scenarios in terms of social impact, technological alternatives, enrollment, and costs. Two parallel channels are assumed open to students under

  17. Cote D'Ivoire (Ivory Coast): World Oil Report 1991

    SciTech Connect

    Not Available

    1991-08-01

    This paper reports on the country's limited oil reserves which are almost exhausted meaning difficult times in the future. New terms for an offer of 11 offshore blocks allow for a negotiable split of cost oil and profit oil linked to either daily production or the ratio between accumulated net revenues and accumulated revenue.

  18. [Necrotizing external otitis in children in Abidjan (Ivory Coast)].

    PubMed

    Akre, E Ette; Akre, A; Tanon, M J; Boguifo, F; N'Guessan, L; Koffi-Aka, V; Adjoua, R P; Kouassi, B; Bamba, M

    2002-01-01

    Necrotizing external otitis (NEO) is a fulminant Pseudomonas infection of the external auditory canal affecting mainly elderly diabetic patients. Since the early descriptions, many authors have related cases of NEO in non diabetic patients. We report eight cases of NEO in young children. They are less than two years old, they are undernourished and non diabetics. We get a good evolution in spite of our modest therapeutic ways. Emphasis is placed on efficiency of local remedy with colistine. PMID:12723486

  19. [Chronic lymphoid leukemia in the Ivory Coast. (69 cases)].

    PubMed

    Toutoukpo, Y; Tea, N; Rain, J D

    1991-01-01

    We report on sixty-nine cases of chronic lymphocytic leukaemia. This report describes the result over a period of eleven years. We have pointed out that chronic lymphocytic leukaemia is most frequent in adults. It occurs on adult (mean age fifty years) with a maximum between forty-one and fifty years old. It is in agreement with others series described elsewhere in Africa. We have noted a predominance in women. The splenomegalia is the predominant clinical sign as it was related also in Africa countries. PMID:1666168

  20. Study of the ablative effects on tektites. [wake shielding during atmospheric entry

    NASA Technical Reports Server (NTRS)

    Sepri, P.; Chen, K. K.

    1976-01-01

    Equations are presented which provide approximate parameters describing surface heating and tektite deceleration during atmosphere passage. Numerical estimates of these parameters using typical initial and ambient conditions support the conclusion that the commonly assumed trajectories would not have produced some of the observed surface markings. It is suggested that tektites did not enter the atmosphere singly but rather in a swarm dense enough to afford wake shielding according to a shock envelope model which is proposed. A further aerodynamic mechanism is described which is compatible with hemispherical pits occurring on tektite surfaces.

  1. Discovery of the most distal Ries tektites found in Lower Silesia, southwestern Poland

    NASA Astrophysics Data System (ADS)

    Brachaniec, Tomasz; Szopa, Krzysztof; Karwowski, ?Ukasz

    2014-08-01

    We report the first occurrence of moldavites in Poland. This discovery confirms the hypothesis that moldavites could have been distributed up to 500 km from the Ries crater in Germany. The tektites were reworked from Middle Miocene sediments and redeposited in Late Miocene (Pannonian) fluvial deposits of the Gozdnicka Formation in Lower Silesia. The Polish moldavites are represented by nine (<8 mm) fragments with a total of 0.471 g. The lack of the autochthonous tektites indicates that tektites investigated here had to be redeposited in a fluvial environment, probably from the Lusatian area. The chemical composition of the Polish moldavites plots in the same area with those from other localities.

  2. New approach to the origin of the tektite in China

    NASA Technical Reports Server (NTRS)

    Qin-Wen, Zhang; Dao-Yi, XU; Zheng, Yan

    1988-01-01

    The tektites in China are distributed on the north part of Australia - Southeastern Asia strewfield of tektite: Leizhou Peninsula of Guangdong Province and Hainan Island, and located exactly at the boundary between Zanjiang Formation and Beihai Formation. A new hypothesis is suggested: During the end of Lower Pleistocene, a comet of special components from the outer part of the Solar System approached the Earth, and then it was captured by the Earth, when it came approximately to the Roche's limet. It was crushed into countless fragments, detritus and dusts, which rotated around the Earth, probably far above the Earth's atmosphere, as a cloud ring. Under the action of crushing energy they could be in the situation of liquid-melt drop in the almost vacuum circumstances and the flow and bubble structure were formed. During their rotation the climate became anomalous and the violet Fe-Si concentration were formed on the surface of sediments. After a rather short time of rotation the unstable ring was broken and the fragments impacted on the hard ground instantaneously.

  3. [Diagnosis of ivory vertebra. Bibliographic study, report of 2 cases of pagetic ivory vertebra].

    PubMed

    Durot, J F; Gatfosse, M; Lerais, J M; Baudrillard, J C; Auquier, F

    1986-04-01

    Two cases are reported of ivory vertebra, an isolated lesion difficult to diagnose clinically or radiologically. Tomographic and if necessary computed tomographic analysis should provide a precise diagnosis of a Paget's disease origin, biopsy being reserved for cases for which a doubt exists. PMID:3761238

  4. Geographic variation of stable isotopes in African elephant ivory

    NASA Astrophysics Data System (ADS)

    Ziegler, S.; Merker, S.; Jacob, D.

    2012-04-01

    In 1989, the international community listed the African elephant in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) thus prohibiting commercial ivory trade. Recent surveillance data show that the illegal trade in ivory has been growing worldwide. Long-term preservation of many of the African elephant populations can be supported with a control mechanism that helps with the implementation of remedial conservation action. Therefore, setting up a reference database that predicts the origin of ivory specimens can assist in determining smuggling routes and the provenance of illegal ivory. Our research builds on earlier work to seek an appropriate method for determining the area of origin for individual tusks. Several researchers have shown that the provenance of elephant ivory can be traced by its isotopic composition, but this is the first attempt to produce an integrated isotopic reference database of elephant ivory provenance. We applied a combination of various routine geochemical analyses to measure the stable isotope ratios of hydrogen, carbon, nitrogen, oxygen, and sulphur. Up to now, we analysed 606 ivory samples of known geographical origin from African range states, museums and private collections, comprising 22 African elephant range states. The isotopic measurements were superimposed with data layers from vegetation, geology and climate. A regression function for the isotope composition of the water isotopes in precipitation and collagen in ivory was developed to overcome the problem of imprecise origin of some of the sampled material. Multivariate statistics, such as nearest neighborhood and discriminate analysis were applied to eventually allow a statistical determination of the provenance for ivory of unknown origin. Our results suggest that the combination of isotopic parameters have the potential to provide predictable and complementary markers for estimating the origin of seized elephant ivory.

  5. XAFS study on Ca local structure in natural glasses and tektite

    NASA Astrophysics Data System (ADS)

    Tobase, T.; Wang, L.; Yoshiasa, A.; Okube, M.; Nakatani, T.; Hayasaka, Y.; Isobe, H.

    2013-04-01

    The local structures of tektite and natural glasses were studied by Ca K-edge X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) in order to provide quantitative data on bonding distances and coordination numbers. The pre-edge peak intensities of tektites are 10.7-11.7%, and those of peudotachylite, Kirauea volcanic glass, impactite, pitchstone and perlite are 6.7-10.9%. The main peak shoulder intensities of tektites are 68.3-70.7%, and other natural glasses are 63.0-63.9%. XAFS analysis indicated all tektites possess 7-coordinated Ca, but natural glasses possess 6-, 7- and 8- coordinated Ca. This study indicated that different petrogenesis of natural glasses gives different local structures of calcium.

  6. Magnetic Properties of Tektites and Related Glasses: Discriminating Among Different Fields and Impactor Component

    NASA Astrophysics Data System (ADS)

    Rochette, P.; Moustard, F.; Gattacceca, J.; Devouard, B.

    2014-09-01

    Magnetic susceptibility of tektites and related glass is a good proxy for total amount of iron, as well as impactor contamination. We present new data from bediasites, ivoirites, atacamaites, Darwin, LDG and Wabar glasses.

  7. Weathering and polymerization of tektites: an x-ray photoelectron spectroscopy (XPS) investigation

    NASA Astrophysics Data System (ADS)

    Biino, Giuseppe G.; Groening, Pierangelo; Meisel, Thomas

    1998-01-01

    Tektites are natural glasses formed from terrestrial material that was melted and displaced by the impact of an extraterrestrial body. The surface and near-surface compositions of tektite glass results from fractionation during impact and ejection, and/or post solidification weathering. The first goal of this study was to characterise the surface and near-surface (in the order of tens of) chemical composition of two tektites by X-ray photoelectron spectroscopy (XPS), and to estimate the importance of weathering versus fractionation during flying. In order to separate the chemical modification due to weathering from that due to fractionation during ballistic flight, we studied two samples from the Australasian tektite strewn field. One of them was collected in a hot desert area (Nullarbor Plain, Australia), the other in humid climate (Thailand). Our study reveals the presence of well-developed leached layers in both tektites. In the Australian tektite, Al is depleted in the top-most layers (a few tens of ). A more complex chemical zoning is defined in the tektite from Thailand. These leached layers are comparable to that observed in weathered glasses, and therefore we conclude that weathering is responsible for the chemical composition of the surface and near-surface. The second goal was to investigate the chemical environment of O, N and C in the glass. The oxygen peak was resolved into two bridging oxygen components (Si-O-Si and Al-O-Si) which are comparable to O environments in artificial glasses. The binding energy of the C1s electron is typical for C-C and C-H bonds in hydrocarbons; minor organic acid components are also present. Nitrogen is only observed on the surface of the Thailand tektite. The binding energy of N1s is comparable to that of ammonia, and the surface enrichment in N is interpreted as due to sorption related to interactions between glass and fluid buffered by the organic material in the soil.

  8. Report of centimeter-sized tektites in Pima County, Arizona, cannot be verified

    NASA Technical Reports Server (NTRS)

    Kring, David A.; Hildebrand, Alan R.; Drake, Michael J.; Melosh, H. Jay; Vickery, Ann M.

    1995-01-01

    Glassy objects reportedly found in Pima County, Arizona, have been identified as tektites. A field survey of the area where they were said to occur, however, did not produce any other tektites, nor did it reveal any other geologic features that might indicate a nearby impact crater. The major-, minor-, and trace-element composition of one specimen is similar to those measured in indochinites, which suggests the objects reportedly from Pima County were instead transported to southern Arizona from Indochina by people.

  9. Nickel-iron spherules in tektites - Non-meteoritic in origin

    NASA Technical Reports Server (NTRS)

    Ganapathy, R.; Larimer, J. W.

    1983-01-01

    The concentrations of several diagnostic trace elements were determined in two comparatively large NiFe spherules extracted from tektites. The purpose of the study was to obtain some clues about the chemistry of the projectile that is presumed responsible for the formation of these tektites. However, the trace element pattern is distinctly terrestrial implying that the spherules are the result of in-situ reduction of the host rock and are not meteoritic in origin.

  10. In search of the Australasian tektite source crater: The Tonle Sap hypothesis

    NASA Astrophysics Data System (ADS)

    Hartung, Jack; Koeberl, Christian

    1994-05-01

    The source crater for Australasian tektites remains to be positively identified. We suggest that Tonle Sap, a roughly oval lake in south-central Cambodia, may represent the remnant of that crater. The size of the lake (about 100 km x 35 km), location (Indochina), inferred geologic age (recent), and orientation of the lake, as well as the geographical distribution of tektites, are consistent with this suggestion. The elongated shape of the lake with its long axis pointing toward Australia may be the result of an oblique impact of a NW to SE-moving object a few km in diameter. The absence of a raised rim and a central peak may be related to a low impact angle, soft target rocks, or high post-impact erosion and sedimentation rates. The scarcity of Muong Nong-type (layered) tektites near Tonle Sap may be due to extensive post-impact alluvial deposition, which buried the tektites. The chemical composition of Upper Indosinias formation sandstones from Phnom Batheay was determined. There are significant differences between the composition of indochinite tektites and these rocks, which are thus unlikely to represent tektite source rocks.

  11. North American tektite debris and impact ejecta from DSDP Site 612

    SciTech Connect

    Glass, B.P. )

    1989-12-01

    A layer of tektite glass and shock-metamorphosed grains found in an upper Eocene section of core 21 from DSDP Site 612 taken on the continental slope off New Jersey may belong to the North American tektite strewn field. In order to better define the layer, a series of samples was taken continuously through the layer at 1 cm intervals. Tektite fragments are in an 8 cm thick layer; microtektites are concentrated in the upper 4 cm, while spherules with crystalline textures (microkrystites) are concentrated in the lower half of the layer. Millimeter-size splash forms are mostly in the lower part of the tektite-bearing layer. Rock and mineral grains showing evidence of shock metamorphism are abundant in the upper half of the tektite-bearing layer. Coesite is abundant, and stishovite was found in one rock fragment. The size and abundance of the tektite glass and the abundance of shocked debris indicate that Site 612 is relatively close to the source crater, which may be to the north of Site 612 on the coastal plain or adjacent continental shelf. 40 refs.

  12. Aerodynamic Analysis of Tektites and Their Parent Bodies

    NASA Technical Reports Server (NTRS)

    Adams, E. W.; Huffaker, R. M.

    1962-01-01

    Experiment and analysis indicate that the button-type australites were derived from glassy spheres which entered or re-entered the atmosphere as cold solid bodies; in case of average-size specimens, the entry direction was nearly horizontal and the entry speed between 6.5 and 11.2 km/sec. Terrestrial origin of such spheres is impossible because of extremely high deceleration rates at low altitudes. The limited extension of the strewn fields rules out extraterrestrial origin of clusters of such spheres because of stability considerations for clusters in space. However, tektites may have been released as liquid droplets from glassy parent bodies ablating in the atmosphere of the earth. The australites then have skipped together with the parent body in order to re-enter as cold spheres. Terrestrial origin of a parent body would require an extremely violent natural event. Ablation analysis shows that fusion of opaque siliceous stone into glass by aerodynamic heating is impossible.

  13. Triple-Oxygen Isotope Composition of Moldavites and Irghizites: Clues for Source Materials of Tektites and Other Impact-related Glasses

    NASA Astrophysics Data System (ADS)

    Magna, T.; k, K.; Pack, A.; Ackerman, L.; Skla, R.; Jonov, .; ?uriov, .; ?anda, Z.; Mizera, J.

    2014-09-01

    High-precision triple-oxygen isotope data for tektite-like glassy irghizites indicate clear addition of meteoritic component, paralleled by high Ni, whilst moldavite tektites have terrestrial oxygen isotope systematics.

  14. Ivory identification by DNA profiling of cytochrome b gene.

    PubMed

    Lee, James Chun-I; Hsieh, Hsing-Mei; Huang, Li-Hung; Kuo, Yi-Chen; Wu, Jane-Hong; Chin, Shih-Chien; Lee, An-Hsing; Linacre, Adrian; Tsai, Li-Chin

    2009-03-01

    Ivory can be visually identified in its native form as coming from an elephant species; however, determining from which of the three extant elephant species a section of ivory originates is more problematic. We report on a method that will identify and distinguish the protected and endangered elephant species, Elephas maximus or Loxodonta sp. To identify the species of elephant from ivory products, we developed three groups of nested PCR amplifications within the cytochrome b gene that generate amplification products using highly degraded DNA isolated from confiscated ivory samples dating from 1995. DNA from a total of 382 out of 453 ivory samples were successfully isolated and amplified leading to species identification. All sequences were searched against GenBank and found to match with E. maximus and Loxodonta sp. with at least 99% similarity. The samples that were tested came from eight Asian elephants, 14 African forest elephants (Loxodonta cyclotis), and 360 African savannah elephants (Loxodonta africana). This study demonstrates a high success rate in species identification of ivory by a nested PCR approach within the cytochrome b gene which provides the necessary information for the protection of endangered species conservation. PMID:18612647

  15. 75 FR 53012 - Culturally Significant Object Imported for Exhibition Determinations: “Ivory Mirror Case”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Object Imported for Exhibition Determinations: ``Ivory Mirror Case'' SUMMARY: Notice..., I hereby determine that the object to be included in the exhibition ``Ivory Mirror Case,''...

  16. 40Ar/39Ar age of Cretaceous-Tertiary boundary tektites from Haiti

    USGS Publications Warehouse

    Izett, G.A.; Dalrymple, G.B.; Snee, L.W.

    1991-01-01

    40Ar/39Ar dating of tektites discovered recently in Cretaceous-Tertiary (K-T) boundary marine sedimentary rocks on Haiti indicates that the K-T boundary and impact event are coeval at 64.5 ?? 0.1 million years ago. Sanidine from a bentonite that lies directly above the K-T boundary in continental, coal-bearing, sedimentary rocks of Montana was also dated and has a 40Ar/39Ar age of 64.6 ?? 0.2 million years ago, which is indistinguishable statistically from the age of the tektites.

  17. Fission track ages and ages of deposition of deep-sea microtektites.

    PubMed

    Gentner, W; Glass, B P; Storzer, D; Wagner, G A

    1970-04-17

    The Australasian and Ivory Coast deep-sea microtektites have fission track ages of 0.71 and 1.09 million years, respectively. These ages are in good agreement with the ages of deposition of the microtektites determined from paleomagnetic data. Both the fission track ages and ages of deposition of the microtektites agree with the potassium/ argon and fission track ages of tektites from the respective tektite strewn fields. PMID:17809131

  18. Artificial tektites: an experimental technique for capturing the shapes of spinning drops

    NASA Astrophysics Data System (ADS)

    Baldwin, Kyle A.; Butler, Samuel L.; Hill, Richard J. A.

    2015-01-01

    Determining the shapes of a rotating liquid droplet bound by surface tension is an archetypal problem in the study of the equilibrium shapes of a spinning and charged droplet, a problem that unites models of the stability of the atomic nucleus with the shapes of astronomical-scale, gravitationally-bound masses. The shapes of highly deformed droplets and their stability must be calculated numerically. Although the accuracy of such models has increased with the use of progressively more sophisticated computational techniques and increases in computing power, direct experimental verification is still lacking. Here we present an experimental technique for making wax models of these shapes using diamagnetic levitation. The wax models resemble splash-form tektites, glassy stones formed from molten rock ejected from asteroid impacts. Many tektites have elongated or `dumb-bell' shapes due to their rotation mid-flight before solidification, just as we observe here. Measurements of the dimensions of our wax `artificial tektites' show good agreement with equilibrium shapes calculated by our numerical model, and with previous models. These wax models provide the first direct experimental validation for numerical models of the equilibrium shapes of spinning droplets, of importance to fundamental physics and also to studies of tektite formation.

  19. Tektites: Origin as melts produced by the impact of small projectiles onto dry targets

    NASA Technical Reports Server (NTRS)

    Wasson, John T.

    1988-01-01

    The formation of tektites in general and layered tektites in particular seems to require a very special kind of cratering event. Evidence for the formation of pools of melt free of unmelted clasts has not been reported for the well-studied terrestrial craters such as Manicouagan or Ries. It is suggested that large amounts of relict-free melt were produced only when a sizeable fraction of the cratered target consisted of dry, high-porosity materials such as aeolian sediments. Since dry, high-porosity target materials are always confined to the outer 100 to 200 m of the Earth, the fraction of melt produced melt is probably higher in small (radius 50 to 500 m) craters than in large (r greater than 1 km) craters. Another reason to infer that the Southeast Asian tektites were produced in a multitude of small craters is the wide distribution of layered tektites. The file spans at least 1200 km, which would require ballistic ejection at velocities greater than 2 km s(-1) if all melt was generated in a single crater. It seems impossible to devise a scenario that would lead to the deposition of primary melt as a crystal-free pool at a distance of 600 km from the crater.

  20. Artificial tektites: an experimental technique for capturing the shapes of spinning drops

    PubMed Central

    Baldwin, Kyle A.; Butler, Samuel L.; Hill, Richard J. A.

    2015-01-01

    Determining the shapes of a rotating liquid droplet bound by surface tension is an archetypal problem in the study of the equilibrium shapes of a spinning and charged droplet, a problem that unites models of the stability of the atomic nucleus with the shapes of astronomical-scale, gravitationally-bound masses. The shapes of highly deformed droplets and their stability must be calculated numerically. Although the accuracy of such models has increased with the use of progressively more sophisticated computational techniques and increases in computing power, direct experimental verification is still lacking. Here we present an experimental technique for making wax models of these shapes using diamagnetic levitation. The wax models resemble splash-form tektites, glassy stones formed from molten rock ejected from asteroid impacts. Many tektites have elongated or ‘dumb-bell' shapes due to their rotation mid-flight before solidification, just as we observe here. Measurements of the dimensions of our wax ‘artificial tektites' show good agreement with equilibrium shapes calculated by our numerical model, and with previous models. These wax models provide the first direct experimental validation for numerical models of the equilibrium shapes of spinning droplets, of importance to fundamental physics and also to studies of tektite formation. PMID:25564381

  1. Tektite 1, Man-in-the-Sea Project: Marine Science Program

    ERIC Educational Resources Information Center

    Clifton, H. Edward; And Others

    1970-01-01

    Describes Project Tektite 1, during which a team of four scientists spent 60 days approximately 15 meters beneath the surface of the sea. Describes the "habitat" in which the men lived, reports biological and geological research carried out, and concludes that this research method has many advantages and potentialities. (EB)

  2. Titanium local structure in tektite probed by X-ray absorption fine structure spectroscopy.

    PubMed

    Wang, Ling; Yoshiasa, Akira; Okube, Maki; Takeda, Takashi

    2011-11-01

    The local structure of titanium in tektites from six strewn fields was studied by Ti K-edge X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) in order to provide quantitative data on Ti-O distance and Ti coordination number. The titanium in tektites possessed different coordination environment types. XANES spectra patterns revealed resemblance to high-temperature TiO(2)-SiO(2) glass and TiO(2) anatase. All samples showed that the valence of Ti is 4+. Based on the Ti-O distances, coordination numbers and radial distribution function determined by EXAFS analyses, the tektites were classified into three types: type I, Ti occupies a four-coordinated tetrahedral site with Ti-O distances of 1.84-1.79?; type II, Ti occupies a five-coordinated trigonal bipyramidal or tetragonal pyramidal site with Ti-O distances of 1.92-1.89?; type III, Ti occupies a six-coordinated octahedral site with Ti-O distances of 2.00-1.96?. Although Ti occupies the TiO(6) octahedral site in most titanium minerals under ambient conditions, some tektites have four- and five-coordinated Ti. This study indicated that the local structure of Ti might change in impact events and the following stages. PMID:21997913

  3. Artificial tektites: an experimental technique for capturing the shapes of spinning drops.

    PubMed

    Baldwin, Kyle A; Butler, Samuel L; Hill, Richard J A

    2015-01-01

    Determining the shapes of a rotating liquid droplet bound by surface tension is an archetypal problem in the study of the equilibrium shapes of a spinning and charged droplet, a problem that unites models of the stability of the atomic nucleus with the shapes of astronomical-scale, gravitationally-bound masses. The shapes of highly deformed droplets and their stability must be calculated numerically. Although the accuracy of such models has increased with the use of progressively more sophisticated computational techniques and increases in computing power, direct experimental verification is still lacking. Here we present an experimental technique for making wax models of these shapes using diamagnetic levitation. The wax models resemble splash-form tektites, glassy stones formed from molten rock ejected from asteroid impacts. Many tektites have elongated or 'dumb-bell' shapes due to their rotation mid-flight before solidification, just as we observe here. Measurements of the dimensions of our wax 'artificial tektites' show good agreement with equilibrium shapes calculated by our numerical model, and with previous models. These wax models provide the first direct experimental validation for numerical models of the equilibrium shapes of spinning droplets, of importance to fundamental physics and also to studies of tektite formation. PMID:25564381

  4. Multicomponent Diffusion between Felsic and Silicic Melts: Insights from Tektites and Experiments

    NASA Astrophysics Data System (ADS)

    Macris, C. A.; Asimow, P. D.; Zhang, Y.; Badro, J.; Stolper, E. M.; Eiler, J. M.

    2014-12-01

    Tektites (natural glasses formed as quenched impact melt ejecta) commonly contain inclusions of nearly pure silica glass ("lechatelierite") thought to be quenched from molten silica produced by melting of quartz grains. We investigated chemical diffusion between lechatelierite (~100% SiO2) and surrounding felsic glass (~73% SiO2) in a natural indochinite tektite and in experimental analogues. We discovered concentration profiles of major elements across lechatelierite-felsic glass contacts that reflect diffusion between the two melts at high T as the they followed a ballistic trajectory prior to quenching. The profiles provide information on multicomponent diffusion at the high-silica end of composition space and on the thermal histories of tektites. To reproduce the profiles, we undertook a series of high T melting experiments using an aerodynamic levitation laser furnace. A starting mixture of powdered natural tektite plus quartz grains was exposed to temperatures of 1800-2400?C for 1-120 s. Direct comparison of concentration profiles between the indochinite and experiments reveals a best match at 2200?C and 50 s. This experiment successfully reproduced all major aspects of the concentration profiles observed in the natural sample including diffusion length scale, asymmetry, order of steepness of major element profiles, and uphill diffusion of K2O. Not enough information is available to model the full multicomponent diffusion problem, but SiO2 and Al2O3 concentration profiles from lechatelierite to surrounding felsic glass in the experiments can be fit well as a diffusion couple between silica melt and adjacent felsic melt using an effective binary diffusion approach and assuming that the effective binary SiO2 and Al2O3 diffusivities depend exponentially on SiO2 concentration. Further quantification of the diffusion behavior should allow constraints on the thermal histories of tektites.

  5. Lithium and Magnesium Isotopes in Sediments of the Ries Area: Constraints on the Sources of Moldavite Tektites

    NASA Astrophysics Data System (ADS)

    Magna, T.; k, K.; Farka, J.; Truba?, J.; Rodovsk, Z.; ime?ek, M.; Skla, R.; ?anda, Z.; Mizera, J.

    2014-09-01

    New Li and Mg isotope data is presented for sediments from the Ries area, considered sources of moldavite tektites. No direct link can be found between Li and specific lithologies while Mg is isotopically lighter in carbonate-rich samples.

  6. Search for the 700,000-year-old source crater of the Australasian tektite strewn field

    NASA Technical Reports Server (NTRS)

    Schnetzler, C. C.; Garvin, J. B.

    1992-01-01

    Many tektite investigations have hypothesized that the impact crater that was the source of the extensive Australasian strewn field lies somewhere in or near Indochina. This is due to variations in abundance and size of tektites across the strewn field, variation of thickness of microtektite layers in ocean cores, nature and ablation characteristics across the field, and, above all, the occurrence of the large, blocky, layered Muong Nong-type tektites in Indochina. A recent study of the location and chemistry of Muong Nong-type and splash-form tektites suggests that the source region can be further narrowed to a limited area in eastern Thailand and southern Loas. Satellite multispectral imagery, a digital elevation dataset, and maps showing drainage patterns were used to search within this area for possible anomalous features that may be large degraded impact craters. Four interesting structures were identified from these datasets, and they are presented.

  7. Illegal killing for ivory drives global decline in African elephants.

    PubMed

    Wittemyer, George; Northrup, Joseph M; Blanc, Julian; Douglas-Hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P

    2014-09-01

    Illegal wildlife trade has reached alarming levels globally, extirpating populations of commercially valuable species. As a driver of biodiversity loss, quantifying illegal harvest is essential for conservation and sociopolitical affairs but notoriously difficult. Here we combine field-based carcass monitoring with fine-scale demographic data from an intensively studied wild African elephant population in Samburu, Kenya, to partition mortality into natural and illegal causes. We then expand our analytical framework to model illegal killing rates and population trends of elephants at regional and continental scales using carcass data collected by a Convention on International Trade in Endangered Species program. At the intensively monitored site, illegal killing increased markedly after 2008 and was correlated strongly with the local black market ivory price and increased seizures of ivory destined for China. More broadly, results from application to continental data indicated illegal killing levels were unsustainable for the species between 2010 and 2012, peaking to ∼ 8% in 2011 which extrapolates to ∼ 40,000 elephants illegally killed and a probable species reduction of ∼ 3% that year. Preliminary data from 2013 indicate overharvesting continued. In contrast to the rest of Africa, our analysis corroborates that Central African forest elephants experienced decline throughout the last decade. These results provide the most comprehensive assessment of illegal ivory harvest to date and confirm that current ivory consumption is not sustainable. Further, our approach provides a powerful basis to determine cryptic mortality and gain understanding of the demography of at-risk species. PMID:25136107

  8. Illegal killing for ivory drives global decline in African elephants

    PubMed Central

    Wittemyer, George; Northrup, Joseph M.; Blanc, Julian; Douglas-Hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P.

    2014-01-01

    Illegal wildlife trade has reached alarming levels globally, extirpating populations of commercially valuable species. As a driver of biodiversity loss, quantifying illegal harvest is essential for conservation and sociopolitical affairs but notoriously difficult. Here we combine field-based carcass monitoring with fine-scale demographic data from an intensively studied wild African elephant population in Samburu, Kenya, to partition mortality into natural and illegal causes. We then expand our analytical framework to model illegal killing rates and population trends of elephants at regional and continental scales using carcass data collected by a Convention on International Trade in Endangered Species program. At the intensively monitored site, illegal killing increased markedly after 2008 and was correlated strongly with the local black market ivory price and increased seizures of ivory destined for China. More broadly, results from application to continental data indicated illegal killing levels were unsustainable for the species between 2010 and 2012, peaking to ?8% in 2011 which extrapolates to ?40,000 elephants illegally killed and a probable species reduction of ?3% that year. Preliminary data from 2013 indicate overharvesting continued. In contrast to the rest of Africa, our analysis corroborates that Central African forest elephants experienced decline throughout the last decade. These results provide the most comprehensive assessment of illegal ivory harvest to date and confirm that current ivory consumption is not sustainable. Further, our approach provides a powerful basis to determine cryptic mortality and gain understanding of the demography of at-risk species. PMID:25136107

  9. Domestication of the Ivory Tower: Institutional Adaptation to Cultural Distance.

    ERIC Educational Resources Information Center

    Barnhardt, Ray

    2002-01-01

    Examines the experiences of Native and non-Native Alaskan teacher educators in rural Alaska, describing opportunities for capitalizing on field settings available to faculty at any university. Discusses reasons for putting faculty in the field, looking at field-based training for Native teachers, the "ivory tower" versus the real world,

  10. Artificial tektites: an experimental technique for capturing the shapes of spinning drops

    NASA Astrophysics Data System (ADS)

    Baldwin, K. A.

    2014-12-01

    Tektites are small stones formed from rapidly cooling drops of molten rock ejected from high velocity asteroid impacts with the Earth, that freeze into a myriad of shapes during flight. Many splash-form tektites have an elongated or dumb-bell shape owing to their rotation prior to solidification[1]. Here we present a novel method for creating 'artificial tektites' from spinning drops of molten wax, using diamagnetic levitation to suspend the drops[2]. We find that the solid wax models produced this way are the stable equilibrium shapes of a spinning liquid droplet held together by surface tension. In addition to the geophysical interest in tektite formation, the stable equilibrium shapes of liquid drops have implications for many physical phenomena, covering a wide range of length scales, from nuclear physics (e.g. in studies of rapidly rotating atomic nuclei), to astrophysics (e.g. in studies of the shapes of astronomical bodies such as asteroids, rapidly rotating stars and event horizons of rotating black holes). For liquid drops bound by surface tension, analytical and numerical methods predict a series of stable equilibrium shapes with increasing angular momentum. Slowly spinning drops have an oblate-like shape. With increasing angular momentum these shapes become secularly unstable to a series of triaxial pseudo-ellipsoids that then evolve into a family of two-lobed 'dumb-bell' shapes as the angular momentum is increased still further. Our experimental method allows accurate measurements of the drops to be taken, which are useful to validate numerical models. This method has provided a means for observing tektite formation, and has additionally confirmed experimentally the stable equilibrium shapes of liquid drops, distinct from the equivalent shapes of rotating astronomical bodies. Potentially, this technique could be applied to observe the non-equilibrium dynamic processes that are also important in real tektite formation, involving, e.g. viscoelastic effects, non-uniform solidification, surface wrinkling (Schlieren), and rapid separation/fission of dumb-bells via the Rayleigh-Plateau instability. [1] M. R. Stauffer and S. L. Butler, Earth Moon Planets, 107, 169 (2009). [2] R. J. A. Hill and L. Eaves, Phys. Rev. Lett. 101, 234501 (2008).

  11. Ti K-edge EXAFS and XANES study on tektites from different strewnfields

    NASA Astrophysics Data System (ADS)

    Wang, L.; Furuta, T.; Okube, M.; Yoshiasa, A.

    2011-12-01

    The concentration and local structure of each element may have various kinds of information about the asteroid impact and mass extinction. Farges and Brown have discussed about the Ti local structure by XANES, and concluded that Ti in tektite occupies 4-coordinated site. EXAFS can be analyzed to give precise information about the distance from Ti to near neighbors. The XAFS measurement of Ti local structure was preformed at the beamline 9C of the Photon Factory in KEK, Tsukuba, Japan. The specimens of tektites are from different strewnfields, they are: indochinite, bediasite, hainanite, philippinite, australite and moldavite. Sample for comparison are Libya desert glass and suevite. The k3?(k) function was transformed into the radial structure function (RSF) for Ti K-edge of six tektites. The RSF for the Ti atom in indochinite and bediasite are similar; hainanite, australite and philippinite are similar; and moldavite is discriminated from others. It indicates that they have the same local atomic environmental around the Ti atoms and extended structure respectively. Coordination numbers and radial structure function are determined by EXAFS analyses (Table 1). We classified the tektites in three types: in indochinite and bediasite, Ti occupies 4-coordinated tetrahedral site and Ti-O distances are 1.84-1.81 ; in hainanite, australite and philippinite, Ti occupies 5-coordinated trigonal bi-pyramidal or tetragonal pyramidal site and Ti-O distances are 1.92-1.87 ; in moldavite, Ti occupies the 6-coordinated octahedral site and Ti-O distance is 2.00-1.96 . Formation of tektites is related to the impact process. It is generally recognized that tektites were formed under higher temperature and high pressure. But through this study, local structures of Ti are differing in three strewnfields and even different locations of the same strewnfield. What caused the various local structures will be another topic of tektite studies. Local structure of Ti may be changed in the impact event and the following stage. Tektites splashed to the space and travel in several kinds of processes and routes, which lead to different temperature and pressure history. Local structure of Ti should be related with the temperature, pressure, quenching rate, sizes of impact meteorite and size of falling melts. [1] Koeberl. Ann.Rev.Earth Planet.Sci. 14, 323-350 (1986) [2] Franois Farges & Gordon E. Brown Jr Geochim. Cosmo. Acta.61, 1863-1870 (1997). [3]Paris, E., Dingwell, D., Seifert, F., Mottana, A. & Romano, C. (1994). Phys. Chem. Miner. 21, 520-525.
    Table 1 Structure parameters determined by EXAFS

  12. Source of the Australasian tektite strewn field - A possible off-shore impact site

    NASA Technical Reports Server (NTRS)

    Schnetzler, C. C.; Walter, L. S.; Marsh, J. G.

    1988-01-01

    Although there is a preponderance of evidence that tektites were formed by asteroid impacts on the earth, no source crater has been found for the largest and youngest of the strewn fields - the Austalasian strewn field. A combined Seasat/Geos 3 altimeter data set of sea surface heights in the northern portion of the Australasian strewn field has been examined for negative gravity anomalies on the continental shelf and slope which might be related to the source crater for these tektites. A large negative anomaly called the Qui Nhon Slope Anomaly is a sea surface depression of approximately 1.5 meters over an area of 100 km diameter. It corresponds to a gravity anomaly of about -50 mgal. It is proposed that this anomaly may be due to the impact structure that produced the Australasian strewn field.

  13. Fourier-transform Raman spectroscopy of ivory: II. Spectroscopic analysis and assignments

    NASA Astrophysics Data System (ADS)

    Edwards, H. G. M.; Farwell, D. W.; Holder, J. M.; Lawson, E. E.

    1997-11-01

    The FT-Raman spectra of African and Asian elephant and woolly mammoth ivory are reported and comprehensive molecular vibrational assignments are proposed. Since ivory is composed of proteinaceous collagen embedded in an inorganic matrix of carbonated hydroxyapatite, the Raman spectrum of pure natural collagen recorded under similar conditions aids the identification of the vibrational modes. Several bands are identified which could be used for the Raman spectroscopic characterisation of the mammalian ivories studied.

  14. Comment on "Ivory-billed woodpecker (Campephilus principalis) persists in continental North America".

    PubMed

    Sibley, David A; Bevier, Louis R; Patten, Michael A; Elphick, Chris S

    2006-03-17

    We reanalyzed video presented as confirmation that an ivory-billed woodpecker (Campephilus principalis) persists in Arkansas (Fitzpatrick et al., Reports, 3 June 2005, p. 1460). None of the features described as diagnostic of the ivory-billed woodpecker eliminate a normal pileated woodpecker (Dryocopus pileatus). Although we support efforts to find and protect ivory-billed woodpeckers, the video evidence does not demonstrate that the species persists in the United States. PMID:16543443

  15. Fourier-transform Raman spectra of ivory III: identification of mammalian specimens

    NASA Astrophysics Data System (ADS)

    Edwards, H. G. M.; Farwell, D. W.; Holder, J. M.; Lawson, E. E.

    1997-11-01

    The FT-Raman spectra of six mammalian ivories, other than elephant and mammoth, are presented and spectral differences formulated into a protocol for the identification of animal species from the ivory samples. In this study, sperm whale, walrus, wart hog, narwhal, hippopotamus and domestic pig are considered. The results, which are obtained non-destructively from a variety of specimens, suggest that FT-Raman spectroscopy provides a potentially useful method for the identification of mammalian ivory.

  16. The chemical durability of tektites - A laboratory study and correlation with long-term corrosion behavior

    NASA Astrophysics Data System (ADS)

    Barkatt, A.; Boulos, M. S.; Barkatt, A.; Sousanpour, W.; Boroomand, M. A.; Macedo, P. B.; O'Keefe, J. A.

    1984-02-01

    Leach tests carried out on tektite specimens (indochinites and australites) under high-dilution conditions show a common behavior characterized by low leach rates (0.00018 g/sq m per d, or 7.2 x 10 to the -12th m/d at 23 C) and an activation energy of (79,600 + or - 700 J/mol). The extent of selective leaching is very small, of the order of 10 to the -8th m. Extrapolation of test results over the lifetime of the tektites gives an excellent agreement with field observations on the extent of corrosion, and this is an important step in establishing the validity of laboratory tests as a basis for the development of models and predictions concerning long-term durabilities at least in the limiting case of high dilution or rapid flow. The results are also shown to be in agreement with various previous observations on the corrosion resistance of tektites. The chemical durability of tektites is observed to be consistent with their composition, highlighting requirements of high corrosion resistance in glasses; these requirements include a silica content in excess of 67 mol percent, an extremely low water content, and an alkali content which is low both absolutely and relative to the di- and poly-valent metal oxide levels. It is shown that artificial glasses which fulfil these criteria are no less corrosion-resistant than the corresponding natural glasses. These conclusions have bearing on the development, as well as on the evaluation, of glasses intended for very long service, such as radioactive waste vitrification media.

  17. Vapor pressure and vapor fractionation of silicate melts of tektite composition

    USGS Publications Warehouse

    Walter, Louis S.; Carron, M.K.

    1964-01-01

    The total vapor pressure of Philippine tektite melts of approximately 70 per cent silica has been determined at temperatures ranging from 1500 to 2100??C. This pressure is 190 ?? 40 mm Hg at 1500??C, 450 ?? 50 mm at 1800??C and 850 ?? 70 mm at 2100?? C. Determinations were made by visually observing the temperature at which bubbles began to form at a constant low ambient pressure. By varying the ambient pressure, a boiling point curve was constructed. This curve differs from the equilibrium vapor pressure curve due to surface tension effects. This difference was evaluated by determining the equilibrium bubble size in the melt and calculating the pressure due to surface tension, assuming the latter to be 380 dyn/cm. The relative volatility from tektite melts of the oxides of Na, K, Fe, Al and Si has been determined as a function of temperature, total pressure arid roughly, of oxygen fugacity. The volatility of SiO2 is decreased and that of Na2O and K2O is increased in an oxygen-poor environment. Preliminary results indicate that volatilization at 2100??C under atmospheric pressure caused little or no change in the percentage Na2O and K2O. The ratio Fe3 Fe2 of the tektite is increased in ambient air at a pressure of 9 ?? 10-4 mm Hg (= 106.5 atm O2, partial pressure) at 2000??C. This suggests that tektites were formed either at lower oxygen pressures or that they are a product of incomplete oxidation of parent material with a still lower ferricferrous ratio. ?? 1964.

  18. The chemical durability of tektites - A laboratory study and correlation with long-term corrosion behavior

    NASA Technical Reports Server (NTRS)

    Barkatt, A.; Boulos, M. S.; Barkatt, A.; Sousanpour, W.; Boroomand, M. A.; Macedo, P. B.; Okeefe, J. A.

    1984-01-01

    Leach tests carried out on tektite specimens (indochinites and australites) under high-dilution conditions show a common behavior characterized by low leach rates (0.00018 g/sq m per d, or 7.2 x 10 to the -12th m/d at 23 C) and an activation energy of (79,600 + or - 700 J/mol). The extent of selective leaching is very small, of the order of 10 to the -8th m. Extrapolation of test results over the lifetime of the tektites gives an excellent agreement with field observations on the extent of corrosion, and this is an important step in establishing the validity of laboratory tests as a basis for the development of models and predictions concerning long-term durabilities at least in the limiting case of high dilution or rapid flow. The results are also shown to be in agreement with various previous observations on the corrosion resistance of tektites. The chemical durability of tektites is observed to be consistent with their composition, highlighting requirements of high corrosion resistance in glasses; these requirements include a silica content in excess of 67 mol percent, an extremely low water content, and an alkali content which is low both absolutely and relative to the di- and poly-valent metal oxide levels. It is shown that artificial glasses which fulfil these criteria are no less corrosion-resistant than the corresponding natural glasses. These conclusions have bearing on the development, as well as on the evaluation, of glasses intended for very long service, such as radioactive waste vitrification media.

  19. Backscattering Mssbauer MIMOS II and XRF studies on tektites from different strewn fields

    NASA Astrophysics Data System (ADS)

    Costa, B. F. O.; Klingelhfer, G.; Panthfer, M.; Alves, E. I.

    2014-04-01

    Room temperature 57Fe Mssbauer spectroscopy has been used to obtain information on the redox and coordination of iron in tektites. A MIMOS II spectrometer in backscattering geometry has been used in the study, so that no sample preparation at all was required. X-ray fluorescence has been used to determine the composition of the tektites. Mssbauer spectra have been deconvoluted using three extended Voigt-based profiles to allow quantitative analysis of iron atoms valence and coordination. In all tektites, the Fesites have been distinguished in Fe with octahedral and tetrahedral coordination. The Feoctahedral sites show a region of isomer shift (IS) and quadrupole splitting (QS), IS 1.02-1.14 mm/s and QS 1.82-2.12 mm/s, relative to -Fe. The Fetetrahedral sites show a region of hyperfine parameters of IS = 0.59-0.89 mm/s and QS = 1.14-1.60 mm/s. The Fe3+sites show IS = 0.11-0.33 mm/s and QS = 0.02-0.04 mm/s. The Fe3+/Fe2+ ratio was found to be 0.025-0.149.

  20. Preliminary discussion on the origin of Lei-gong-mo (tektites)

    NASA Technical Reports Server (NTRS)

    Baoyin, Y.

    1983-01-01

    The specimens of lei-gong-mo (tektites) were collected from Hainan Island and Leizhow Peninsula during the period from 1963 to 1975. The distribution, forms, sculpture, abration surface (bald spot), internal structure and chemical composition of lei-gong-mo are discussed. Studies of these materials lead to the following conclusions: (1) the specimens of lei-gong-mo can be morphologically divided into eight types; (2) the sculptures on the surface of lei-gong-mo are probably due to the corrosion effect of volcanic gas, and the abration surface due to the aerodynamic corrosion; (3) the folded structures in the layered lei-gong-mo (Muong Nong-type tektite) seem hardly to be formed by an impact of meteorites, but they might be produced in the magma flow process when the lei-gong-mo was melting within the crater vent; and (4) the comparison of its chemical composition with that of basalt from Hainan Island does not show that lei-gong-mo came from the local volcano. The hypothesis of the lunar volcanic origin of tektites is examined.

  1. Age and provenance of the target materials for tektites and possible impactites as inferred from Sm-Nd and Rb-Sr systematics

    NASA Technical Reports Server (NTRS)

    Shaw, H. F.; Wasserburg, G. J.

    1982-01-01

    Chemical, trace element, and isotopic compositions of tektites are consistent with production by melting of sediments derived from the old terrestrial continental crust. Each tektite group is characterized by a uniform Nd model age, interpreted as the time of formation of the crustal segment which weathered to form the parent sediment for the tektites. Sr model ages are variable within each group, reflecting Rb-Sr fractionation, and, in the favorable limit of very high Rb/Sr ratios, approach the time of sedimentation of the parent material which melted to form the tektites. Unlike tektites, which are dense homogeneous objects, sanidine spherules are porous, fine grained inhomogeneous objects. The leaching experiment employed by the present study shows that the sanidine spherules could have been formed by an oceanic impact involving basaltic crust and overlying sediments or seawater.

  2. 76 FR 15047 - Port of Ivory, LLC-Operation Exemption-Line of Railroad in Tulare County, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... Surface Transportation Board Port of Ivory, LLC--Operation Exemption--Line of Railroad in Tulare County, CA Port of Ivory, LLC (Port), a limited liability company and noncarrier, has filed a verified notice... Valley Railroad Company (SJVR) at a point known as Ivory (milepost 232.3 on SJVR's Exeter...

  3. Chemical composition of sawdust from lunar rock 12013 and comparison of a Java tektite with the rock.

    NASA Technical Reports Server (NTRS)

    Showalter, D. L.; Wakita, H.; Schmitt, R. A.; Gillum, D. E.; Ehmann, W. D.; Smith, R. H.

    1972-01-01

    Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements shows that no fragment of sawdust or rock 12013 that has been analyzed to date is chemically similar to tektite glass. Rock sawdust is representative of ?whole rock' composition only if the amount of contamination from the sawing process is known. After appropriate correction for saw wire contamination, analyses of sawdust yield fairly accurate averaged elemental compositions of complex clastic lunar and other rocks.

  4. Chemical composition of sawdust from lunar rock 12013 and comparison of a java tektite with the rock.

    PubMed

    Showalter, D L; Wakita, H; Smith, R H; Schmitt, R A; Gillum, D E; Ehmann, W D

    1972-01-14

    Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements shows that no fragment or sawdust of rock 12013 that has been analyzed to date is chemically similar to tektite glass. Rock sawdust is representative of "whole rock" composition only if the amount of contamination from the sawing process is known. After appropriate correction for saw wire contamination, analyses of sawdust yield fairly accurate averaged elemental compositions of complex clastic lunar and other rocks. PMID:17771802

  5. Tektites in Cretaceous-Tertiary boundary rocks on Haiti and their bearing on the Alvarez impact extinction hypothesis

    USGS Publications Warehouse

    Izett, G.A.

    1991-01-01

    Relic tektites are associated with a Pt-group metal abundance anomaly and shocked minerals in a thin marl bed that marks the K-T boundary on Haiti. The presence of these three impact-produced materials at the precise K-T boundary enormously strengthens the Alvarez impact extinction hypothesis. The Haitian tektites are the first datable impact products in K-T boundary rocks, and 40Ar-39Ar ages of the glass show that the K-T boundary and impact event are coeval at 64.5 ?? 0.1 Ma. -from Author

  6. Durabiliy of two simulated nuclear waste glasses, a frit glass, and tektite in aqueous solutions: Final report, Volume I

    SciTech Connect

    Hagen, D.A.; Altstetter, C.J.; Brown, S.D.

    1988-05-01

    High level nuclear waste is commonly incorporated into glass for disposal. Therefore the long term aqueous durability of the waste glass is important. The leaching behavior of three simulated nuclear waste glasses (AH10, AH165, and Frit 165) and a natural glass (tektite) were examined using nuclear reaction analysis, leachate solution analysis, and microscopy. The three simulated waste glasses developed hydrated layers which increased in thickness by t/sup /1/2//. The hydrated layer in Frit 165 reached a constant thickness of about one micron. Alkali were preferentially removed from the Frit 165 and AH10. The tektite corroded by slow uniform dissolution. 94 refs., 68 figs., 13 tabs.

  7. Field recovery of layered tektites in northeast Thailand: Evidence of a large-scale melt sheet

    NASA Astrophysics Data System (ADS)

    Wasson, J. T.; Pitakpaivan, K.; Fiske, P.; Puttapiban, P.; Salapongse, S.; Thapthimthong, B.; McHone, J. F.

    1994-07-01

    Field searches and interrogation of farmers in Thailand has led to the recovery of layered Australasian tektites in-situ throughout a region extending from the Laotian border westward to a line connecting Ban Pho Klang near the Mekong River in the northeast through Det Udom to Nam Yun in the south. With two exceptions in sites near the western edge of this region, all recovered fragments are layered. The layering of layered tektites appears to have formed by downslope flow. The structures closely resemble layering found in obsidian flows, and the 20 deg dip of the magnetic remanence relative to the layering shows that the glass masses were in-situ on the Earth's surface when they cooled through the Curie temperature. This seems to require that the region was continuously heated by radiation associated with the accretion of extraterrestrial material until the melt had rained out onto the surface; to achieve the observed amount of flow a mean radiation temperature of approximately 2200 K was required. The highly luminous sky was partly produced by fireballs above the parental impact craters, but also by Tunguska-like atmospheric phenomena produced by infalling projectiles that released their entire energy in the atmosphere and left no crater record. We suggest that the investigated region was covered with a melt sheet. A rough estimate is that the mean thickness of the layer was approximately 4 mm, corresponding to a surface density of 10 kg/sq m. An equally rough estimate of the density of tektites that survived weathering and is still present in pristine regions is approximately 30 g/sq m.

  8. Tektite 2 habitability research program: Day-to-day life in the habitat

    NASA Technical Reports Server (NTRS)

    Nowlis, D. P.

    1972-01-01

    Because it is widely agreed that the field of environmental psychology is quite young, it was determined that a sample of recorded observations from a representative mission should be included in the report on Tektite to give the professional reader a better feeling of normal day-to-day life in the isolated habitat. Names of the crew members have been replaced with numbers and some off-color words have been replaced by more acceptable slang; some remarks have been omitted that might lead to easy identification of the subjects. Otherwise, the following pages are exactly as transcribed during the late afternoons and the evenings of the mission.

  9. Theory of Tumbling Bodies Entering Planetary Atmospheres with Application to Probe Vehicles and the Australian Tektites

    NASA Technical Reports Server (NTRS)

    Tobak, Murray; Peterson, Victor L.

    1964-01-01

    The tumbling motion of aerodynamically stable bodies entering planetary atmospheres is analyzed considering that the tumbling, its arrest, and the subsequent oscillatory motion are governed by the equation for the fifth Painleve' transcendent. Results based on the asymptotic behavior of the transcendent are applied to study (1) the oscillatory behavior of planetary probe vehicles in relation to aerodynamic heating and loads and (2) the dynamic behavior of the Australian tektites on entering the Earth's atmosphere, under the hypothesis that their origin was the Moon.

  10. Some alkali and titania analyses of tektites before and after G-1 precision monitoring

    USGS Publications Warehouse

    Tatlock, D.B.

    1966-01-01

    A comparison of 55 older analyses of Australasian tektites with 110 modern precisely monitored analyses suggests that more than half of the older alkali and titania determinations are decidedly inaccurate and misleading. Deviations of the older analyses from the restricted values of the modern analyses are comparable to the imprecisions shown by early analyses of G-1 granite and W-1 diabase. This suggests that a high percentage of older alkali and titania analyses, such as those of Washington's tables, are of questionable quality. ?? 1966.

  11. Meteoroid mayhem in Ole Virginny: source of the North American tektite strewn field

    USGS Publications Warehouse

    Poag, C.W.; Powars, D.S.; Poppe, L.J.; Mixon, R.B.

    1994-01-01

    New seismic reflection data from Chesapeake Bay reveal a buried, 85-km-wide, 1.5-2.0-km-deep, peak-ring impact crater, carved through upper Eocene to Lower Cretaceous sedimentary strata and into underlying pre-Mesozoic crystalline basement rocks. A polymictic, late Eocene impact breccia, composed mainly of locally derived sedimentary debris (determined from four continuous cores), surrounds and partly fills the crater. Structural and sedimentary characteristics of the Chesapeake Bay crater closely resemble those of the Miocene Ries peak-ring crater in southern Germany. It is speculated that the Chesapeake Bay crater is the source of the North American tektite strewn field. -Authors

  12. Impact origin of the Chesapeake Bay structure and the source of the North American tektites

    USGS Publications Warehouse

    Koeberl, C.; Poag, C.W.; Reimold, W.U.; Brandt, D.

    1996-01-01

    Seismic profiles, drill core samples, and gravity data suggest that a complex impact crater ???35.5 million years old and 90 kilometers in diameter is buried beneath the lower Chesapeake Bay. The breccia that fills the structure contains evidence of shock metamorphism, including impact melt breccias and multiple sets of planar deformation features (shock lamellae) in quartz and feldspar. The age of the crater and the composition of some breccia clasts are consistent with the Chesapeake Bay impact structure being the source of the North American tektites.

  13. Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field

    USGS Publications Warehouse

    Poag, C. Wylie; Powars, David S.; Poppe, Lawrence J.; Mixon, Robert B.

    1994-01-01

    New seismic reflection data from Chesapeake Bay reveal a buried, 85-km-wide, 1.5-2.0-km-deep, peak-ring impact crater, carved through upper Eocene to Lower Cretaceous sedimentary strata and into underlying pre-Mesozoic crystalline basement rocks. A polymictic, late Eocene impact breccia, composed mainly of locally derived sedimentary debris (determined from four continuous cores), surrounds and partly fills the crater. Structural and sedimentary characteristics of the Chesapeake Bay crater closely resemble those of the Miocene Ries peakring crater in southern Germany. We speculate that the Chesapeake Bay crater is the source of the North American tektite strewn field.

  14. Histogenesis of the unique morphology of proboscidean ivory.

    PubMed

    Virg, Attila

    2012-12-01

    The chequered pattern (often called Schreger pattern), which can be seen by unaided eye on transverse profiles of several proboscidean tusks and which can be emphasized by the spreading pattern of the cracks or by mineral discoloration, is an autapomorph feature of the clade Elephantoidea. The pattern differs among proboscidean taxa; therefore, it allows the coarse differentiation of elephants, mammoths, and some other basal groups. Such identification methods could facilitate efforts concerned with protection of the remaining elephant populations through ivory trade restrictions, since the tooth dentine from extinct Mammuthusprimigenius and from extant Loxodontaafricana and Elephasmaximus are the most common raw materials of the ivory carvings. The aim of this study was to show the internal structure of proboscidean ivory and to revise the existing theories on the aforementioned pattern of the elephantoids with reflections on the events which lead to the development of this microstructure. Thin sections and natural crack surfaces with various orientations of M.primigenius, Elephasantiquus, Prodeinotherium, and Deinotherium tusk fragments were used to produce a three-dimensional model which explains the features on all profiles. The "phase shift" model is introduced, which assumes a sinusoid undulation of the dentinal tubules in radial profiles in the case of elephantoids. The model was confirmed by photomicrographs, scanning electron microscopic images, interpretation of natural crack surfaces, and radial displacement analysis of the dentinal tubules. The latter proved that the adjacent waves are not in the same phase. Several new nondestructive distinguishing methods are described here on the basis of the correlation between some microscopic and macroscopic features related to the Schreger pattern. PMID:22949298

  15. Biodegradation of ivory (natural apatite): possible involvement of fungal activity in biodeterioration of the Lewis Chessmen.

    PubMed

    Pinzari, Flavia; Tate, James; Bicchieri, Marina; Rhee, Young Joon; Gadd, Geoffrey Michael

    2013-04-01

    Fungal biodeterioration of ivory was investigated with in vitro inoculation of samples obtained from boar and walrus tusks with the fungi Aspergillus niger and Serpula himantioides, species of known geoactive abilities. A combination of light and scanning electron microscopy together with associated analytical techniques was used to characterize fungal interactions with the ivory, including changes in ivory composition, dissolution and tunnelling, and the formation of new biominerals. The research was aimed at providing further understanding of the potential roles of fungi in the colonization and deterioration of ivory in terrestrial environments, but also contributes to our knowledge regarding the possible origins of the surface damage observed on early medieval sculptures made largely from walrus tusks, referred to as 'the Lewis hoard of gaming pieces', that were presumably produced for playing chess. The experiments have shown that the possibility of damage to ivory being caused by fungi is realistic. Scanning electron microscopy revealed penetration of fungal hyphae within cracks in the walrus tusk that showed also widespread tunnelling by fungal hyphae as well as 'fungal footprints' where the surface was etched as a consequence of mycelial colonization. Similar phenomena were observed with boar tusk ivory, while production of metabolites could lead to complete dissolution of the sample. Colonization of ivory and/or exposure to fungal activity lead to extensive secondary biomineral formation, and this was identified as calcium oxalate, mainly as the monohydrate, whewellite. PMID:23157656

  16. Comparison of the magnetic properties and Mossbauer analysis of glass from the Cretaceous-Tertiary boundary, Beloc, Haiti, with tektites

    NASA Technical Reports Server (NTRS)

    Thorpe, A. N.; Senftle, F. E.; May, L.; Barkatt, A.; Adel-Hadadi, M. A.; Marbury, G. S.; Izett, G. A.; Maurrasse, F. R.

    1994-01-01

    The magnetic properties of black Beloc glass have been measured. The Curie constant, the magnetization, and the magnetic susceptibility of the Beloc glass fall within the known ranges observed for tektites. However, the temperature-independent component of the magnetic susceptibility is slightly higher than that found for tektites. Moreover, it is not possible to match the experimental magnetic data for the Beloc glass with the calculated values using the previously reported Fe(3+)/Fe(2+) ratio of 0.7. The oxidation state of Fe was therefore redetermined by Mossbauer measurements, and the Fe(3+)/Fe(2+) ratio was found to be 0.024 plus or minus 0.015. Using the redetermined value of the ratio, the magnetic parameters were again calculated using formulas that are applicable to tektites, and good agreement was found between the calculated and experimental values. The experimental magnetic measurements and the redetermined Fe(3+)/Fe(2+) ratio of the Beloc glass specimens are essentially the same as those found for tektite glass.

  17. Using DNA to track the origin of the largest ivory seizure since the 1989 trade ban

    PubMed Central

    Wasser, Samuel K.; Mailand, Celia; Booth, Rebecca; Mutayoba, Benezeth; Kisamo, Emily; Clark, Bill; Stephens, Matthew

    2007-01-01

    The illegal ivory trade recently intensified to the highest levels ever reported. Policing this trafficking has been hampered by the inability to reliably determine geographic origin of contraband ivory. Ivory can be smuggled across multiple international borders and along numerous trade routes, making poaching hotspots and potential trade routes difficult to identify. This fluidity also makes it difficult to refute a country's denial of poaching problems. We extend an innovative DNA assignment method to determine the geographic origin(s) of large elephant ivory seizures. A Voronoi tessellation method is used that utilizes genetic similarities across tusks to simultaneously infer the origin of multiple samples that could have one or more common origin(s). We show that this joint analysis performs better than sample-by-sample methods in assigning sample clusters of known origin. The joint method is then used to infer the geographic origin of the largest ivory seizure since the 1989 ivory trade ban. Wildlife authorities initially suspected that this ivory came from multiple locations across forest and savanna Africa. However, we show that the ivory was entirely from savanna elephants, most probably originating from a narrow east-to-west band of southern Africa, centered on Zambia. These findings enabled law enforcement to focus their investigation to a smaller area and fewer trade routes and led to changes within the Zambian government to improve antipoaching efforts. Such outcomes demonstrate the potential of genetic analyses to help combat the expanding wildlife trade by identifying origin(s) of large seizures of contraband ivory. Broader applications to wildlife trade are discussed. PMID:17360505

  18. Legal ivory trade in a corrupt world and its impact on African elephant populations.

    PubMed

    Bennett, Elizabeth L

    2015-02-01

    Illegal hunting of African elephants (Loxodonta africana) for ivory is causing rapid declines in their populations. Since 2007, illegal ivory trade has more than doubled. African elephants are facing the most serious conservation crisis since 1989, when international trade was banned. One solution proposed is establishment of a controlled legal trade in ivory. High prices for ivory mean that the incentives to obtain large quantities are high, but the quantity of tusks available for trade are biologically constrained. Within that context, effective management of a legal ivory trade would require robust systems to be in place to ensure that ivory from illegally killed elephants cannot be laundered into a legal market. At present, that is not feasible due to corruption among government officials charged with implementing wildlife-related legislation. With organized criminal enterprises involved along the whole commodity chain, corruption enables the laundering of illegal ivory into legal or potentially legal markets. Poachers and traffickers can rapidly pay their way out of trouble, so the financial incentives to break the law heavily outweigh those of abiding by it. Maintaining reliable permitting systems and leak-proof chains of custody in this context is challenging, and effective management breaks down. Once illegal ivory has entered the legal trade, it is difficult or impossible for enforcement officers to know what is legal and illegal. Addressing corruption throughout a trade network that permeates countries across the globe will take decades, if it can ever be achieved. That will be too late for wild African elephants at current rates of loss. If we are to conserve remaining wild populations, we must close all markets because, under current levels of corruption, they cannot be controlled in a way that does not provide opportunities for illegal ivory being laundered into legal markets. PMID:25103555

  19. Using DNA to track the origin of the largest ivory seizure since the 1989 trade ban.

    PubMed

    Wasser, Samuel K; Mailand, Celia; Booth, Rebecca; Mutayoba, Benezeth; Kisamo, Emily; Clark, Bill; Stephens, Matthew

    2007-03-01

    The illegal ivory trade recently intensified to the highest levels ever reported. Policing this trafficking has been hampered by the inability to reliably determine geographic origin of contraband ivory. Ivory can be smuggled across multiple international borders and along numerous trade routes, making poaching hotspots and potential trade routes difficult to identify. This fluidity also makes it difficult to refute a country's denial of poaching problems. We extend an innovative DNA assignment method to determine the geographic origin(s) of large elephant ivory seizures. A Voronoi tessellation method is used that utilizes genetic similarities across tusks to simultaneously infer the origin of multiple samples that could have one or more common origin(s). We show that this joint analysis performs better than sample-by-sample methods in assigning sample clusters of known origin. The joint method is then used to infer the geographic origin of the largest ivory seizure since the 1989 ivory trade ban. Wildlife authorities initially suspected that this ivory came from multiple locations across forest and savanna Africa. However, we show that the ivory was entirely from savanna elephants, most probably originating from a narrow east-to-west band of southern Africa, centered on Zambia. These findings enabled law enforcement to focus their investigation to a smaller area and fewer trade routes and led to changes within the Zambian government to improve antipoaching efforts. Such outcomes demonstrate the potential of genetic analyses to help combat the expanding wildlife trade by identifying origin(s) of large seizures of contraband ivory. Broader applications to wildlife trade are discussed. PMID:17360505

  20. Trace-element composition of Chicxulub crater melt rock, K/T tektites and Yucatan basement

    NASA Technical Reports Server (NTRS)

    Hildebrand, A. R.; Gregoire, D. C.; Attrep, M., Jr.; Claeys, P.; Thompson, C. M.; Boynton, W. V.

    1993-01-01

    The Cretaceous/Tertiary (K/T) boundary Chicxulub impact is the best preserved large impact in the geologic record. The Chicxulub crater has been buried with no apparent erosion of its intracrater deposits, and its ejecta blanket is known and is well preserved at hundreds of localities globally. Although most of the molten material ejected from the crater has been largely altered, a few localities still preserve tektite glass. Availability of intra- and extracrater impact products as well as plausible matches to the targeted rocks allows the comparison of compositions of the different classes of impact products to those of the impacted lithologies. Determination of trace-element compositions of the K/T tektites, Chicxulub melt rock, and the targeted Yucatan silicate basement and carbonate/evaporite lithologies have been made using instrumental neutron activation analysis (INAA) and inductively coupled plasma mass spectrometry (ICP-MS). Some sample splits were studied with both techniques to ensure that inter-laboratory variation was not significant or could be corrected. The concentration of a few major and minor elements was also checked against microprobe results. Radiochemical neutron activation analysis (RNAA) was used to determine Ir abundances in some samples.

  1. Masses of the Impactor, the Australasian Tektites, and Size Estimates of the Main Source Crater

    NASA Astrophysics Data System (ADS)

    Schmidt, G.; Wasson, J. T.

    1993-07-01

    New estimates of the total masses of tektites and Ir fallout in the Australasian strewnfield offer information about the crater diameter of the large source crater or craters that launched Australasian tektites and Australasian microtektites into extra-atmospheric trajectories 0.77 Ma ago. Australasian microtektites (<1 mm diameter) have been found in many deep-sea sediments, though generally at moderate fluences (only one value >200 cm^-2) [1]. Recently, cores having exceptionally high microtektite fluences (>1000 cm^-2) have been discovered: ODP hole 758B [2] and ODP holes 767B and 769A [3]. Analyses of sediments from ODP 758B (Eastern Indian Ocean) and from ODP 769A (Sulu Sea) near SE Asia show small Ir enhancements associated with the microtektites. We determined a net Ir fluence of 2.0 +- 0.5 ng cm^-2 in 758B and a less well-defined value of 1.3 +- 0.6 ng cm^-2 in 769A [4]. Addition of the new cores to the set studied by Burns [4] yields a microtektite distribution that exponentially decreases outward from southeast Asia, the fluence dropping a factor of 2 in ~400 km. In southeast Asia the trend merges with a roughly estimated mass fluence of ~0.9 g cm^-2 inferred from evidence of a melt sheet in NE Thailand. Integration of the inferred distribution yields a total mass of Australasian tektites of 2.7 x 10^16 g, 270X greater than the Glass et al. value of 10^14 g commonly cited in the literature. We can use the Ir fluence of 2.0 ng cm^2 in the main peak of core 758B and the assumption that the fallout pattern was the same as that of the tektites to estimate the mass of the impacting body. The microtektite fluence in the main peak in 758B is 3970 cm^2 corresponding to a mass fluence of 7.94 x 10^-2 g cm^2. Multiplying the Ir/microtektite mass ratio times the integrated tektite mass of 2.7 x 10^16 g yields an Ir mass of 6.8 x 10^17 ng. Assuming that the non-icy part of the projectile consisted of chondritic matter having an Ir concentration of 600 ng/g, we calculate the mass of the impacting body to be 1.1 x 10^15 g. A typical density of 3.6 g cm^-3 yields a volume of 3.1 x 10^14 cm^3 and thus a sphere with a radius of 420 m. A mean Ir content of KT boundary sediments of 80 ng cm^2 corresponds to a mass of the KT impactor of 6.8 x 10^17 g of CM-chondrite-like material, 620X greater than our inferred mass of the Australasian impactor. The inferred mass of the body responsible for the Eltanin impact is 2.5 x 10^14 g, 4X smaller than that calculated for the Australasian impactor. If, as numerous people have suggested, the projectile that produced the tektites was a comet, the chondritic matter would have been accompanied by a roughly equal mass of H2O ice and the total volume was 1.4 x 10^15 cm^3, corresponding to a sphere of radius 700 m. The collision of such bodies with the Earth at an asteroidal (as opposed to cometary velocity) of 20 km s^-1 would release of 2.2 x 10^20 J (chondrite) or 4.4 x 10^20 J (comet), sufficient to excavate craters having diameters 14 and 17 km, respectively, assuming a simple scaling relationship. The approximate mass required to produce a 10-km crater is one-half and one- quarter, respectively, of our estimated masses for the chondritic and cometary projectiles. Thus the formation of a crater large enough to launch tektites through the atmosphere is consistent with the formation of a multitude of smaller craters required to account for the layered tektites [5]. The most probable location of the missing large crater is in the Mekong Valley, in mountainous areas experiencing high erosion rates, or buried beneath Mekong sediments. References: [1] Burns (1990) Ph.D. thesis, Univ. of Delaware. [2] Smit et al. (1991) Proc. ODP, Sci. Res., 121, 489-503. [3] Schneider et al. (1992) EPSL, 111, 395-405; [4] Schmidt et al. (1993) GCA, submitted; [5] Wasson (1991) EPSL, 102, 95-109.

  2. Petrographic and petrological studies of lunar rocks. [Apollo 15 breccias and Russian tektites

    NASA Technical Reports Server (NTRS)

    Winzer, S. R.

    1978-01-01

    Clasts, rind glass, matrix glass, and matrix minerals from five Apollo 15 glass-coated breccias (15255, 15286, 15465, 15466, and 15505) were studied optically and with the SEM/microprobe. Rind glass compositions differ from sample to sample, but are identical, or nearly so, to the local soil, suggesting their origin by fusion of that soil. Most breccia samples contain green or colorless glass spheres identical to the Apollo 15 green glasses. These glasses, along with other glass shards and fragments, indicate a large soil component is present in the breccias. Clast populations include basalts and gabbros containing phases highly enriched in iron, indicative of extreme differentiation or fractional crystallization. Impact melts, anorthosites, and minor amounts of ANT suite material are also present among the clasts. Tektite glasses, impact melts, and breccias from the Zhamanshin structure, USSR, were also studied. Basic tektite glasses were found to be identical in composition to impact melts from the structure, but no satisfactory parent material has been identified in the limited suite of samples available.

  3. Isotopic signatures of black tektites from the K-T boundary on Haiti - Implications for the age and type of source material

    NASA Technical Reports Server (NTRS)

    Premo, W. R.; Izett, G. A.

    1992-01-01

    An isotopic study was carried out to characterize the type of black tektites from the Cretaceous-Tertiary (K-T) boundary on Haiti (the first reasonably well-preserved impact-derived material recovered from the K-T boundary), in order to help characterize the tektite source material (i.e., the type of rocks that were melted and ejected during the impact event(s) at around 64.5 Ma). Results show that the isotopic data and all of the element concentration data obtained are consistent with an andesitic-dacitic composition for the tektites and their source material. The Nd isotopic data suggest that the source rocks were not older than Silurian (T(chur) = 400 Ma) in age, and were composed largely of young (less than 1080 Ma) crustal material. Of the suspected K-T boundary impact sites, both the Manson (Iowa) and Chicxulub (Yucatan) structures occur in suitable lithologies to yield the Haitian black tektites.

  4. Accretionary lapilli, tektites, or concretions: the ubiquitous spherules of Meridiani Planum

    NASA Astrophysics Data System (ADS)

    DiGregorio, Barry E.

    2004-11-01

    One of the most enigmatic discoveries made by the NASA Mars Exploration Rover Opportunity (MER-B) at the Meridiani Planum landing site are the ubiquitous spherules referred to as "blueberries" by the science team. They cover the entire landing area and can be seen in every direction within view of the rover cameras. Subsequent analysis of a small grouping of the spherules laying on top of a rock outcrop by Mossbauer spectroscopy showed an intense hematite signature not found on the rock or in the surrounding basaltic soils. Spherules were also found attached to and embedded within sedimentary sulfate rock outcrops found at the landing area that have been determined by the MER science team as having been formed in an acidic liquid water environment. The appearance of most of the Meridiani spherules is strikingly similar to the morphology and size of terrestrial accretionary lapilli and show similarities to terrestrial tektites. Accretionary lapilli are spherical balls and fragments with a concentric layered structure that are formed by a variety of mechanisms including hydrovolcanic eruptions, geysers and large meteorite impacts in water. Tektites are glassy impact spherules that form as a result of large meteorite impacts and also seem apparent in some of the rover images. Tektites can be perfectly spherical or have teardrop and dumbbell shapes. A lack of a visible volcanic source capable of producing high volumes of accretionary lapilli as seen in the MER-B images, in combination with the strong spectral signature of hematite, that some of the spherules display, led the MER science team to favor a concretion hypothesis thus far. All of these types of spherules involve interaction of with surface water or ice to form. Problems exist in explaining how the Martian "concretions", if that is indeed what they are, are of such uniform size and have such a wide distribution. Evidence from Martian orbit and on the surface indicate that the Meridiani Planum landing ellipse is located within an ancient 800 km diameter impact structure with another 140 km crater under the site. Estimated hydrothermal output from this size of an impact would be equivalent to 38 times Yellowstone over a 15,000 year time period. Life as we understand it is dependent on a source of liquid water, energy, and nutrients. Hydrothermal energy can originate from either internal volcanic sources or through the action of large bolide impact. A 25 km diameter fluidized ejecta (rampart) crater named Victoria is located 50 km to the southwest of the Opportunity rover landing site and might explain how the Meridiani Planum region is covered with such an enormous abundance of spherules.

  5. Tektite 1, man-in-the-sea project: Marine Science Program

    USGS Publications Warehouse

    Clifton, H.E.; Mahnken, C.V.W.; Van Derwalker, J. C.; Waller, R.A.

    1970-01-01

    The Tektite experiment was designed to provide data for a number of behavioral, biomedical, and engineering studies in addition to the marine sciences program. Conditions for some of these studies were not altogether compatible with the program for the marine sciences. For example, isolation imposed by human behavioral studies precluded physical contact with the surface team, even though such contact was physically possible and desirable for the conduct of the marine sciences program. Isolation also imposed on the scientific team the duty of all in-habitat maintenance, both scheduled and unscheduled, thereby taking substantial time from scientific research. In addition, between 10 and 20 percent of the waking time was devoted to performance of psychological tests required for the biomedical studies. Most of the experiments were directed toward detecting potentially adverse changes and thus were accepted as necessary and desirable. The only health problem to affect the scientific program during the dive was a minor external ear infection contracted by all the divers. Nonetheless, the experiment demon. strated, at least to our satisfaction, the advantages of underwater habitation and saturation diving for biological and geological research. A major advantage is the opportunity for continuous monitoring of organisms or processes. In addition, underwater habitation provides for considerably more research time in the water than surface diving or intermittent bottom dwelling, and this advantage increases greatly as the depth of habitation increases. Even in the relatively shallow depths at which Tektite 1 was conducted, the undersea team could spend appreciably more time at work in the water than their colleagues on the surface. Finally, Tektite 1 demonstrated that the scientist who lives in the sea need not have the extensive qualifications of a professional diver. Of the four scientists of the in-habitat team, only Crew Chief Waller was so qualified; the other three had used scuba as a research tool, but on a relatively limited basis. Any healthy, well-conditioned marine scientist with a basic diving background is capable of extending his research into the shallow sea on a full-time basis. It is hoped that many such scientists will in the future be able to utilize the undersea laboratory.

  6. The diffraction grating in the Ivory optomechanical modeling tools

    NASA Astrophysics Data System (ADS)

    Hatheway, Alson E.

    2013-09-01

    In imaging spectrometers it is important that both the image of the far-field object and the image of the slit be stable on the detector plane. Lenses and mirrors contribute to the motions of these images but motions of the diffraction grating also have their own influences on these image motions. This paper develops the vector equations for the images (spectra) of the diffraction grating and derives their optomechanical influence coefficients from them. The Ivory Optomechanical Modeling Tools integrates the diffraction grating into the larger optical imaging system and formats the whole system's influence coefficients suitably for both spreadsheet and finite element analysis methods. Their application is illustrated in an example of a spectrometer exposed to both static and dynamic disturbances.

  7. Chemical variability of Cleistopholis patens (Benth.) Engl. et Diels leaf oil from ivory coast.

    PubMed

    Ouattara, Zana Adama; Boti, Jean Brice; Attioua, Koffi Barthelemy; Ahibo, Antoine Coffy; Casanova, Joseph; Tomi, Félix; Bighelli, Ange

    2013-11-01

    The chemical composition of 48 leaf oil samples isolated from individual plants of Cleistopholis patens (Benth.) Engl. et Diels harvested in four Ivoirian forests was investigated by GC-FID (determination of retention indices), GC/MS, and (13) C-NMR analyses. The main components identified were β-pinene (traces-59.1%), sabinene (traces-54.2%), (E)-β-caryophyllene (0.3-39.3%), linalool (0.1-38.5%), (E)-β-ocimene (0.1-33.2%), germacrene D (0.0-33.1%), α-pinene (0.1-32.3%), and germacrene B (0-21.2%). The 48 oil compositions were submitted to hierarchical clustering and principal components analyses, which allowed the distinction of three groups within the oil samples. The oil composition of the major group (GroupI, 33 samples) was dominated by (E)-β-caryophyllene and linalool. The oils of Group II (eight samples) contained mainly β-pinene and α-pinene, while those of Group III (seven samples) were dominated by sabinene, limonene, and β-phellandrene. Moreover, the compositions of the Ivoirian C. patens leaf oils differed from those of Nigerian and Cameroonian origins. PMID:24243614

  8. Television for the Rural African Village: Studies of Audiences and Impact in the Ivory Coast.

    ERIC Educational Resources Information Center

    Seya, Pierre Thizier; Yao, Faustin Kouadjo

    The two surveys described in this report were conducted for the Out of School Television (OSTV) unit in order to learn more about the context in which its series of weekly programs for rural adults (Tele Pour Tous or Television for Everybody--TVE) operates, and to study audience reactions to a specific series. Individual interviews with selected

  9. [Protein profile and vitamin A in children of school age in Ivory Coast].

    PubMed

    Yapi, H F; Ahiboh, H; Ago, K; Aké, M; Monnet, D

    2005-01-01

    The purpose of this transverse prospective study was to determine blood nutritional, immunity and inflammatory proteins change in vitamin A deficiency in children of school-age (262 children, aged 7 to 15 years). Blood vitamin A has been determined by HPLC with UV detection. Proteins have been measured by radial immunodiffusion according to Mancini. Results showed that 96 children (36.6%) presented a vitamin A deficiency (vitamin A < 200 microg/L with a retinol binding protein/transthyretin molar ratio = 0.29 +/- 0.06) while 166 (63.3%) children presented normal blood concentrations of vitamin A (vitamin A > or = 200 microg/L with a Retinol Binding Protein/Transthyretin molar ratio = 0.40 +/- 0.08). This study showed that the retinol binding protein and the immunoglobulin A are lower in children with vitamin A deficiency. On the other hand, an isolated increase of alpha-1 glycoprotein acid has been observed in boys with vitamin A deficiency. The vitamin A deficiency observed in this survey is due to a micronutrients deficiency in the diet which is essentially based on glucides. The positive correlation between vitamin A and immunoglobulin A concentrations might be the result of the vitamin A inductive effect during immunoglobulins A synthesis. The isolated increasing of alpha-1 glycoprotein acid in boys with vitamin A deficiency has been assigned to the ecosensitiveness of the unfavourable environment. We therefore concluded that, in Ivorian primary-school-aged children with vitamin A deficiency, nutritional, immunity and inflammatory proteins which are modified are respectively retinol binding protein, immunoglobulin A and alpha-1 glycoprotein acid. PMID:15951260

  10. [Surveillance of enteroviruses in the waste water of the Ivory Coast].

    PubMed

    Gershy-Damet, G M; Lanusse, A; Dosso, M

    1987-01-01

    Viral water contamination is on the increase all over the world and one is concerned by the dangers to which it exposes health and preoccupied with the search for effective solutions. This study, which was conducted in a year in Cte-d'Ivoire, enabled us to examine the degree of viral pollution from waste water collected from a lagune. It allowed us to follow the distribution of enteroviruses and their fluctuations during the year. 164 waste water samples were tested and 93 enterovirus strains isolated. 67.89% showed polioviruses and 32.11% coxsackieviruses. Seasonal fluctuations of the virus concentration in the lagune water were shown from statistical analysis of the data collected. Concentration was high during the rainy season and definitely lower during the dry season with the rise in water temperature. PMID:3038356

  11. Integrated water pollution assessment of the Ebri Lagoon, Ivory Coast, West Africa

    NASA Astrophysics Data System (ADS)

    Scheren, P. A. G. M.; Kroeze, C.; Janssen, F. J. J. G.; Hordijk, L.; Ptasinski, K. J.

    2004-01-01

    An environmental pollution assessment of the Ebri lagoon, the largest coastal ecosystem in Western Africa, was executed by applying the Driving force-Pressure-State-Impacts-Response (DPSIR) framework. The domestic and industrial activities in Abidjan and agricultural activities in the wider catchment area were identified as the main driving forces. Two-thirds of Biological Oxygen Demand (BOD) loads and 95% of total nitrogen (N) and phosphorous (P) loads of Abidjan are from domestic effluents, with industry making up the rest. Outside of the direct influence of Abidjan, nutrient levels in the lagoon are governed by the influx of nutrients from the rivers Como, M and Agnby, with nutrient land runoff as the key factors. Total annual N loads to the lagoon for 2000 are estimated at 33 kt, of which 45% from urban sources, 42% from land runoff and 13% from atmospheric deposition. Estimates for P are 2.5 kt, 39%, 48% and 13%, respectively. Scenario analysis has shown that autonomous growth, without pollution reduction measures, would result in an estimated five-fold increase in nutrient inputs to the lagoon over the period 1980-2050. Nutrient concentrations in the lagoon would consequently increase by a factor of 3 1/2, which could escalate to a dramatic level of eutrophication for the complete system. Pollution reduction policies aimed at non-point sources would be most effective in reducing nutrient concentrations. Point-source pollution reduction would improve conditions around Abidjan, but not substantially in the other sections of the lagoon. The approach taken in this study has proven efficient under conditions of relative data scarceness, and sufficiently reliable to allow for policy level conclusions to be drawn.

  12. Life promises and 'failed' family ties: expectations and disappointment within a clinical trial (Ivory Coast).

    PubMed

    Marcis, F Le

    2015-12-01

    Building on fieldwork carried out in a clinical trial looking at early antiretroviral treatment for HIV in Abidjan, this paper aims to analyse the way relations emerge during trials and the consequences of the end of participation. Instead of discussing it using the register of ethics, understood as a universal set of principles, the trial is analysed for what it means locally for its actors, mainly patients. From this standpoint, the trial can be defined as both a promise of life and of new possibilities embodied in what is often described as new family ties. How are such ties formed and what does it mean when these ties are broken at the end of patient participation? Discussing the failure of family ties commented upon by patients and dealt by physician researcher is a way to look at ethics from below. PMID:26361643

  13. Draft genome sequences of two closely-related aflatoxigenic Aspergillus species obtained from the Ivory Coast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genomes of the A. ochraceoroseus and A. rambellii type strains were sequenced using a personal genome machine, followed by annotation of their genes. The genome size for A. ochraceoroseus was found to be approximately 23 Mb and contained 7,837 genes, while the A. rambellii genome was found to be...

  14. [Evaluation of multidrug-resistant tuberculosis treatment in Ivory Coast from 2008 to 2010].

    PubMed

    Ahui, B J-M; Horo, K; Bakayoko, A S; Kouassi, A B; Anon, J C; Brou-Gode, V C; Koffi, M O; Itchy, M V; N'Gom, A S; N'Goran, N B; Aka-Danguy, E

    2013-12-01

    This is a retrospective study conducted from January 2008 to December 2010 on sectional descriptive analysis of records of patients treated for MDR-TB and whose follow-up was in the thoracic department of Centre Hospitalier Universitaire (CHU) of Cocody in Abidjan Cte d'Ivoire. We selected eight patients who met the inclusion criteria of 21MDR-TB patients registered during the study period. The average age was 29.25years ranging from 21 to 39. Males accounted for 75% of the patients (6 males and 2 females). The students represented the professional social layer most affected with 37.5% of the patients. All patients had a history of tuberculosis and only one patient was HIV positive under anti-retroviral (zidovudin, lamivudin and efavirenz). All cultures found Mycobacterium tuberculosis. The resistance profile in addition to isoniazid and rifampicin, found two cases of resistance to ethambutol and streptomycin. The chest radiograph at the time of initiation of second-line treatment showed essentially excavations in 75% of cases and infiltrates in 25%. The lesions were bilateral in 7 of 8 patients (87.5%). The main side effects observed during treatment were limited to cochleovestibular disorders (2patients) and neuropsychiatric disorders (2patients) and digestive disorders in half of the patients with removal of the offending molecule kanamycin. After 24months of treatment, it was numbered five cures (62.5%), two failures and one death. PMID:24183291

  15. [Antimalarial guidelines and therapy practices of the population of Bouake, Ivory Coast].

    PubMed

    Dossou-Yovo, J; Amalaman, K; Carnevale, P

    2001-01-01

    This survey of 162 households in the city of Bouaké, Côte d'Ivoire was undertaken to study the behavior of the population in diagnosing and treating malaria. Findings indicate that awareness of symptoms and ability to evaluate the severity of malaria is high. In most cases, mild malaria is treated at home. In case of presumptive diagnosis of malaria, 87.6% of households undertake self-treatment, 9.3% seek institutional healthcare, 1.2% go to traditional healers, and 1.9% use traditional remedies. The most frequent drug for primary treatment is chloroquine (68.3%) which is generally obtained from pharmacies (98.8%). However, proper dosages are rarely used. If primary treatment fails, behavior is complex depending on the estimated severity of disease. Although many causes of malaria are mentioned, most people implicate mosquitoes (75.6%). In 95.1% of households surveyed, chloroquine prophylaxis was used for newborns. Most households (89.5%) practice mosquito bite protection but use of mosquito nets is low (4.9%). These results showing the preference for family-based management suggest that informational campaigns are needed to promote effective and consistent home treatment. Education is also needed to increase knowledge about mosquito nets and insecticides. PMID:11980399

  16. 57FE Mssbauer spectroscopy studies of Tektites from Khon Kaen, Ne Thailand

    NASA Astrophysics Data System (ADS)

    Costa, B. F. O.; Klingelhfer, G.; Alves, E. I.

    2014-01-01

    Room temperature 57Fe Mssbauer effect spectroscopy has been used to investigate the local Fe environment in a set of indochinite tektites from Thailand. A MIMOS II spectrometer in backscattering geometry has been used in the study, so that no sample preparation at all was required. The spectra have been analysed in terms of discrete spectral components using Voigt functions. The results are similar to those obtained with analysis done with quadrupole splitting distributions. In all cases the Mssbauer spectra show a broadened asymmetric quadrupole split doublet. The Fe 2+ sites have been distinguished in Fe with octahedral and tetrahedral coordination. The Fe3+ /Fe2+ and Fe2+ tetrahedral/octahedral ratios have been determined from the relative areas of the various spectral components. Their values have been discussed in the light of actual literature.

  17. Some effects of gas adsorption on the high temperature volatile release behavior of a terrestrial basalt, tektite and lunar soil

    NASA Technical Reports Server (NTRS)

    Graham, D. G.; Muenow, D. W.; Gibson, E. K., Jr.

    1979-01-01

    Mass pyrograms obtained from high-temperature, mass psectrometric pyrolysis of a glassy theoleiitic submarine basalt and a tektite, ground in air to less than 64 microns, have shown N2 and SO release patterns very similar to those from the pyrolysis of mature lunar soil fines. The N2 and CO release behavior from the terrestrial samples reproduces the biomodal, high-temperature (approximately 700 and 1050 C) features from the lunar samples. Unground portions of the basalt and tektite show no release of N2 and CO during pyrolysis. Grinding also alters the release behavior and absolute amounts of H2O and CO2. It is suggested that adsorption of atmospheric gases in addition to solar wind implantation of ions may account for the wide range of values in previously reported concentrations of carbon and nitrogen from lunar fines.

  18. Science education in rural America: Adaptations for the ivory tower

    NASA Astrophysics Data System (ADS)

    van Doren, Gregory S.

    This thesis illustrated what can happen when academic culture disconnects from the cultures surrounding it. It showed that formal school environments are not always the best places to learn. A discussion of the debate between coherence and fragmentation learning theories illustrated academic chasms and a mindset that science education must originate from within ivory towers to be valued. Rationales for place-based science education were developed. Two National Science Foundation initiatives were compared and contrasted for relevance to Native Science education (a) Informal Science Education and (b) Science Education for New Civic Engagement and Responsibilities. A National Science Foundation instrument, known as the Self-Assessment of Learning Gains, was selected to field-test measures of learning science outside of university science courses. Principles of chemistry were taught in community workshops, and those participant self-assessments were compared to self-assessments of students in introductory chemistry courses at two universities. University students consistently claimed the greatest learning gains, in the post-course survey, for the same areas that they claimed to have the greatest understanding, in the pre-course survey. The workshop participant responses differed, depending upon location of the learning environment. When held in a university laboratory, ideas were not related to other cultures, even when a Native Elder was present to describe those relationships. When held in a cultural center, those relationships were among the highest learning gains claimed. One of the instrument's greatest assets was the ability to measure reactions, level 4 of Bennett's (1976) hierarchy of evidence for program evaluation. A long-term commitment to informal science education (not short-term exhibits or programs), combined with negotiated place-based education was recommended as a crucially needed initiative, if relationships between universities and Native American communities are to improve. Some chasms created within ivory towers may never be bridged. Yet, those ideological chasms do not have to exist everywhere. The realities of working in the natural world and the practice of addressing multitudes of community challenges can alter perspectives, when horizons change from the edge of one's desk to those that meet the sea or sky.

  19. Coast Guard

    SciTech Connect

    Meed, R.M.

    1991-10-01

    This paper testifies that water pollution by oil remains significant, and noncompliance with federal regulations to prevent oil pollution continues to be great in the four ports GAO visited. Additionally, the impact of the Coast Guard's efforts to reduce oil spill in unknown because the agency does not compile and analyze inspection and spill data needed to make this determination. Further, the Coast Guard has not been inspecting portions of pipes that transport oil between docks and storage tanks. Coast Guard officials now acknowledge this responsibility.

  20. Mid-Pleistocene divergence of Cuban and North American ivory-billed woodpeckers.

    PubMed

    Fleischer, Robert C; Kirchman, Jeremy J; Dumbacher, John P; Bevier, Louis; Dove, Carla; Rotzel, Nancy C; Edwards, Scott V; Lammertink, Martjan; Miglia, Kathleen J; Moore, William S

    2006-09-22

    We used ancient DNA analysis of seven museum specimens of the endangered North American ivory-billed woodpecker (Campephilus principalis) and three specimens of the species from Cuba to document their degree of differentiation and their relationships to other Campephilus woodpeckers. Analysis of these mtDNA sequences reveals that the Cuban and North American ivory bills, along with the imperial woodpecker (Campephilus imperialis) of Mexico, are a monophyletic group and are roughly equidistant genetically, suggesting each lineage may be a separate species. Application of both internal and external rate calibrations indicates that the three lineages split more than one million years ago, in the Mid-Pleistocene. We thus can exclude the hypothesis that Native Americans introduced North American ivory-billed woodpeckers to Cuba. Our sequences of all three woodpeckers also provide an important DNA barcoding resource for identification of non-invasive samples or remains of these critically endangered and charismatic woodpeckers. PMID:17148432

  1. Obsidians and tektites: Natural analogues for water diffusion in nuclear waste glasses

    SciTech Connect

    Mazer, J.J.; Bates, J.K.; Bradley, C.R.; Stevenson, C.M.

    1991-11-01

    Projected scenarios for the proposed Yucca Mountain repository include significant periods of time when high relative humidity atmospheres will be present, thus the reaction processes of interest will include those known to occur under these conditions. The ideal natural analog for the proposed Yucca Mountain repository would consist of natural borosilicate glasses exposed to expected repository conditions for thousands of years; however, the prospects for identifying such an analog are remote, but an important caveat for using natural analog studies is to relate the reaction processes in the analog to those in the system of interest, rather than a strict comparison of the glass compositions. In lieu of this, identifying natural glasses that have reacted via reaction processes expected in the repository is the most attractive option. The goal of this study is to quantify molecular water diffusion in the natural analogs obsidian and tektites. Results from this study can be used in assessing the importance of factors affecting molecular water diffusion in nuclear waste glasses, relative to other identified reaction processes. In this way, a better understanding of the long-term reaction mechanism can be developed and incorporated into performance assessment models. 17 refs., 4 figs.

  2. Coast Guard

    SciTech Connect

    Not Available

    1990-02-01

    GAO found the situation in the Philadelphia and New York ports similar to that in Prince William Sound-neither industry nor the Coast Guard are prepared to respond to major oil spills. This report discusses how this unpreparedness is due to a lack of specificity in the industry and Coast Guard's plan on how to deal with spills of various sizes and Coast Guard authority to require ship owners and operators to have contingency plans or to require changes in existing plans. On the basic of recent experiences, GAO believes that prevention of oil spills rather than responding to them should be the main priority. Experiences in Price William Sound and in Philadelphia, however, show that much needs to be done to improve prevention measures like monitoring and guiding ship movements and using harbor pilots or vessel escorts.

  3. Coast Guard

    SciTech Connect

    Not Available

    1991-09-01

    The 11-million gallon Exxon Valdez oil spill highlighted deficiencies in the nation's ability to contain and recover spilled oil. The Oil Pollution Act of 1990 represents a major effort by Congress to address these deficiencies and to clarify the roles and responsibilities of the private sector and the federal government in preventing, preparing for, and responding to oil spills. This report examines the Coast Guard's efforts to avoid unnecessary and wasteful duplication by coordinating with the private sector and others, including federal and state agencies, its plans to buy oil spill response equipment and the new responsibilities the act places on the private sector and the Coast Guard and if these responsibilities call for a shift in emphasis in Coast Guard oil spill response activities.

  4. California Coast

    Atmospheric Science Data Center

    2014-05-15

    ... the top. The left image is a color composite generated using data from the blue, green, and red bands of the vertical (nadir) camera. The ... stratus cloud layer; to their west at the edge of the cloud bank is San Nicolas Island, and further up the coast are the Channel Islands. ...

  5. Geochemistry and ND-SR isotope signature of tektite-like objects from Siberia (urengoites, south-Ural glass)

    NASA Astrophysics Data System (ADS)

    Deutsch, Alexander; Ostermann, Markus; Masaitis, Victor L.

    1997-09-01

    We report Sr-Nd isotope parameters, REE, and major element data for isolated findings of tektite-like objects from Western Siberia (urengoites, South-Ural glass), as well as for two indochinites. The latter were recovered in Vietnam and their overall geochemical characteristics equal those of other tektites from the indochinite subgroup of the Australasian strewn field. The three about 24 Ma urengoites are extremely silica-rich (89 to 96 wt% SiO2); and their REE abundances vary between 45 and 76 ppm. With LaN/YbN ranging from 7.6 to 10.4, and EuN/Eu between 0.69 and 0.75, their REE distribution patterns match that of average upper crust. The urengoites have present day Sr of +155 to +174, and Nd ranging from -18 to -23. Their model ages in [Ma] are: TSrUR = 1200 up to 4060 and TNdCHUR = 1570 up to 2070. Data points for the urengoites plot colinear in the Rb-Sr evolution diagram. The age corresponding to the slope is 183 30 Ma (2), indistinguishable from the intercept age of 211 Ma in the TSrUR vs. 1/fRb diagram. Rb-Sr and Sm-Nd systematics of the urengoites indicate a heterogeneous precursor material, derived from Paleoproterozoic continental crust, which underwent Rb/Sr fractionation and partial Sr isotope homogenization in Jurassic times. Any relation between the urengoites and the Haughton impact crater, having within 2 ( errors an identical age, can be excluded on the basis of isotope relationships and geochemical data. The only known, about 6.2 Ma South-Ural glass is characterized by intermediate SiO2 (65 wt%), high Al2O3 (14 wt%) and CaO (12 wt%), and low FeOTOT (0.4 wt%) contents. This unique tektite-like object contains 110 ppm REE displaying a steeply negative C1 normalized distribution with LaN/YbN of 17, and EuN/Eu of 0.71. Rb abundance (10 ppm) and Rb/Sr ratio are low, and combined with a "crustal" 87Sr/86Sr ratio of 0.722, yielding an unrealistic TSrUR age of 2.5 Ga. The Rb-Sr systematics imply a rather recent parent/daughter element decoupling. The TNd CHUR age of the South-Ural glass is about 1690 Ma. Geochemical data suggest that urengoites and the South-Ural glass belong to two discrete groups of tektites, whose source craters remain to be discovered.

  6. Unusual appearance of Schreger-like pattern in Hippopotamus amphibius ivory: wildlife forensics investigation of a netsuke.

    PubMed

    Sims, Margaret E

    2010-07-15

    The National Fish and Wildlife Forensics Laboratory routinely receives confiscated wildlife parts and products (including ivory) for identification purposes as part of wildlife law enforcement casework. Identification of evidentiary ivory typically involves a detailed and comprehensive visual and microscopic examination of the objects, as well as observation with ultraviolet light. Of thousands of ivory objects examined at the Lab, the author has observed unusual non-Proboscidean (elephant) objects with Schreger-like (cross-hatched) pattern. One of these objects was a small well-polished netsuke carved from a hippopotamus canine. PMID:20451339

  7. 75 FR 41886 - Recovery Plan for the Ivory-billed Woodpecker (Campephilus principalis)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    .... The draft recovery plan was completed and released for public comment on August 22, 2007 (72 FR 47064... Fish and Wildlife Service Recovery Plan for the Ivory-billed Woodpecker (Campephilus principalis...-billed Woodpecker (Campephilus principalis). This final recovery plan includes criteria and measures...

  8. Dating ivory by determination of 14C, 90Sr and 228/232Th.

    PubMed

    Schmied, Stefanie A K; Brunnermeier, Matthias J; Schupfner, Robert; Wolfbeis, Otto S

    2012-09-10

    A method is described to determine the time of death of elephants. This is accomplished by analysis of the radionuclides 14C, 90Sr and 228/232Th in known samples of ivory, and in samples of unknown age. The reliability of this method is considerably increased by multi nuclide analysis. PMID:22717552

  9. Nurturing and Validating Indigenous Epistemologies in Higher Education: Comment on "Domestication of the Ivory Tower."

    ERIC Educational Resources Information Center

    Romero, Mary Eunice

    2002-01-01

    Responds to a paper that focused on the "domestication of the ivory tower" and that highlighted indigenous, field-based education associated with higher education institutions in Alaska. Shares two stories that illustrate what indigenous students often encounter in higher education, places of learning that frequently devalue or ignore their world

  10. Asians in the Ivory Tower: Dilemmas of Racial Inequality in American Higher Education. Multicultural Education Series

    ERIC Educational Resources Information Center

    Teranishi, Robert T.

    2010-01-01

    Highly respected scholar Robert Teranishi draws on his vast research to present this timely and compelling examination of the experience of Asian Americans in higher education. "Asians in the Ivory Tower" explores why and how Asian Americans and Pacific Islanders (AAPIs) are important to our nation's higher education priorities and places the

  11. Combating the illegal trade in African elephant ivory with DNA forensics.

    PubMed

    Wasser, Samuel K; Joseph Clark, William; Drori, Ofir; Stephen Kisamo, Emily; Mailand, Celia; Mutayoba, Benezeth; Stephens, Matthew

    2008-08-01

    International wildlife crime is burgeoning in this climate of global trade. We contend that the most effective way to contain this illegal trade is to determine where the wildlife is being removed. This allows authorities to direct law enforcement to poaching hot spots, potentially stops trade before the wildlife is actually killed, prevents countries from denying their poaching problems at home, and thwarts trade before it enters into an increasingly complex web of international criminal activity. Forensic tools have been limited in their ability to determine product origin because the information they can provide typically begins only at the point of shipment. DNA assignment analyses can determine product origin, but its use has been limited by the inability to assign samples to locations where reference samples do not exist. We applied new DNA assignment methods that can determine the geographic origin(s) of wildlife products from anywhere within its range. We used these methods to examine the geographic origin(s) of 2 strings of seizures involving large volumes of elephant ivory, 1 string seized in Singapore and Malawi and the other in Hong Kong and Cameroon. These ivory traffickers may comprise 2 of the largest poaching rings in Africa. In both cases all ivory seized in the string had common origins, which indicates that crime syndicates are targeting specific populations for intense exploitation. This result contradicts the dominant belief that dealers are using a decentralized plan of procuring ivory stocks as they became available across Africa. Large quantities of ivory were then moved, in multiple shipments, through an intermediate country prior to shipment to Asia, as a risk-reduction strategy that distances the dealer from the poaching locale. These smuggling strategies could not have been detected by forensic information, which typically begins only at the shipping source. PMID:18786100

  12. Coast Guard

    SciTech Connect

    Not Available

    1991-06-01

    This paper reports that about 16,000 oil spills involving the release of more than 46 million gallons of oil took place in U.S. navigable waters in 1988; spills at water-front facilities, where vessels load and unload oil, accounted for about half of the oil spilled. While the Coast Guard acknowledges its responsibility for regulating and inspecting waterfront facilities, it efforts in this area have fallen short because it has not been inspecting portions of intrafacility pipes that transport oil between docks and storage tanks. Water pollution and noncompliance with federal oil pollution prevention regulations continue to be high at waterfront facilities. Yet the Coast Guard cannot determine how effective its inspection program has been in reducing the risk of oil spills because information on program results, such as the types, severity, and frequency of deficiencies found by inspectors, is not compiled an linked with information on the causes of oil spills found by investigators. Until the Coast Guard collects this type of information, it will not be in a position to establish measurable goals.

  13. Re-Evaluation of the Chesapeake Bay Crater Impact Age: New ^4^0Ar-^3^9Ar Step-Heating Results for North American Tektites

    NASA Astrophysics Data System (ADS)

    Fernandes, V. A.; Hopp, J.; Schwarz, W.; Trieloff, M.; Reimold, W. U.

    2012-03-01

    Reevaluation of Chesapeake Bay crater impact age is being undertaken by ^4^0Ar-^3^9Ar step-heating of NA tektites and impact melt found within the USGS-ICDP drill core Eyreville-B. Initial results suggest a slightly younger age than the accepted 35.3 Ma.

  14. Neodymium and strontium isotopic study of Australasian tektites - New constraints on the provenance and age of target materials

    NASA Technical Reports Server (NTRS)

    Blum, Joel D.; Papanastassiou, D. A.; Wasserburg, G. J.; Koeberl, C.

    1992-01-01

    The Nd and Sr isotopic compositions of Australasian tectites (including two flanged Australian tectites, two low-SiO2 Muong Nong-type tectites, and three high-SiO2 Muong Nong-type tectites) and the Nd, Sm, Sr, and Rb concentrations were investigated by isotope-dilution thermal ionization mass spectrometry, and the Sm-Nd and Rb-Sr isotope systematics were used to study the characteristics of the parental material. It is shown that the Nd and Sr isotopic data provide evidence that all Australasian tektites were derived from a single sedimentary formation with a narrow range of stratigraphic ages close to 170 Ma. It is suggested that all of the Australasian tektites were derived from a single impact event and that the australites represent the upper part of a melt sheet ejected at high velocity, whereas the indochinites represent melts formed at a lower level in the target material distributed closer to the area of the impact.

  15. Heat induced transformation of fossil mastodon ivory into turquoise 'odontolite'. Structural and elemental characterisation

    NASA Astrophysics Data System (ADS)

    Reiche, I.; Vignaud, C.; Menu, M.

    2000-10-01

    The present work deals with the structural and elemental analysis of turquoise mineral imitations as 'odontolite' or bone turquoise by transmission electron microscopy (TEM), scanning electron microscopy (SEM-EDX) and particle induced X-ray and γ-ray emission (PIXE-PIGE). The aim of the work is to evidence the former deliberate transformation of fossilised ivory by man in order to transform them into semi-precious stones. We show that the crystal structure of 'odontolite' artefacts consisting of fluorapatite (Ca 5(PO 4) 3F) corresponds to that of heated fossil mastodon ivory (12-15 million years old). Metallic traces detected by PIXE-PIGE in these 'odontolites' are discussed in order to explain their role for coloration. Other more greenish turquoise imitations have a bone-like structure and composition, and carbonate-hydroxylapatite. The presence of copper salts at the surface is responsible for their green coloration.

  16. A Sustainable Substitute for Ivory: the Jarina Seed from the Amazon

    PubMed Central

    Chu, Yinghao; Meyers A, Marc A.; Wang, Bin; Yang, Wen; Jung, Jae-Young; Coimbra, Carlos F. M.

    2015-01-01

    The dried endosperm of the seed of Phytelephas sp is widely used for artisanal work in the Amazon region due to its favorable mechanical properties and pleasant appearance that resemble elephant ivory. While the seeds have enjoyed popularity and limited use by selected industries (e.g., military uniform buttons and piano keys) and handicraft applications, little is known about the mechanical properties and structure of this sustainable material. This work is the first to characterize the dried Jarina endosperm and to investigate its functionality as a viable substitute for elephant ivory. Structural analysis of typical seeds reveals the prevalence of tubules that align in rings and radiate from the (usually hollow) core of the seed. This seed, in the absence of a reinforcement structure or mineral phase, possesses mechanical properties slightly inferior to elephant ivory and selected plastics, while retaining the visual appeal of a naturally occurring material. A synthetic structure inspired on the seed is created and suggestions for further development are discussed. PMID:26399626

  17. A Sustainable Substitute for Ivory: the Jarina Seed from the Amazon.

    PubMed

    Chu, Yinghao; Meyers, A Marc A; Wang, Bin; Yang, Wen; Jung, Jae-Young; Coimbra, Carlos F M

    2015-01-01

    The dried endosperm of the seed of Phytelephas sp is widely used for artisanal work in the Amazon region due to its favorable mechanical properties and pleasant appearance that resemble elephant ivory. While the seeds have enjoyed popularity and limited use by selected industries (e.g., military uniform buttons and piano keys) and handicraft applications, little is known about the mechanical properties and structure of this sustainable material. This work is the first to characterize the dried Jarina endosperm and to investigate its functionality as a viable substitute for elephant ivory. Structural analysis of typical seeds reveals the prevalence of tubules that align in rings and radiate from the (usually hollow) core of the seed. This seed, in the absence of a reinforcement structure or mineral phase, possesses mechanical properties slightly inferior to elephant ivory and selected plastics, while retaining the visual appeal of a naturally occurring material. A synthetic structure inspired on the seed is created and suggestions for further development are discussed. PMID:26399626

  18. A Sustainable Substitute for Ivory: the Jarina Seed from the Amazon

    NASA Astrophysics Data System (ADS)

    Chu, Yinghao; Meyers A, Marc A.; Wang, Bin; Yang, Wen; Jung, Jae-Young; Coimbra, Carlos F. M.

    2015-09-01

    The dried endosperm of the seed of Phytelephas sp is widely used for artisanal work in the Amazon region due to its favorable mechanical properties and pleasant appearance that resemble elephant ivory. While the seeds have enjoyed popularity and limited use by selected industries (e.g., military uniform buttons and piano keys) and handicraft applications, little is known about the mechanical properties and structure of this sustainable material. This work is the first to characterize the dried Jarina endosperm and to investigate its functionality as a viable substitute for elephant ivory. Structural analysis of typical seeds reveals the prevalence of tubules that align in rings and radiate from the (usually hollow) core of the seed. This seed, in the absence of a reinforcement structure or mineral phase, possesses mechanical properties slightly inferior to elephant ivory and selected plastics, while retaining the visual appeal of a naturally occurring material. A synthetic structure inspired on the seed is created and suggestions for further development are discussed.

  19. The identification of elephant ivory evidences of illegal trade with mitochondrial cytochrome b gene and hypervariable D-loop region.

    PubMed

    Lee, Eun-jung; Lee, Yang-han; Moon, Seo-hyun; Kim, Nam-ye; Kim, Soon-hee; Yang, Moon-sik; Choi, Dong-ho; Han, Myun-soo

    2013-04-01

    DNA analysis of elephant ivory of illegal trade was handled in this work. The speciation and geographical origin of nine specimens of elephant ivory were requested by the police. Without national authorization, the suspect had purchased processed ivory seals from January to May, 2011 by Internet transactions from a site in a neighboring country. The DNA of decalcified ivory evidences was isolated with QIAGEN Micro Kit. The total 844-904 base pair sized sequences of mitochondrial cytochrome b and D-loop region could be acquired using direct sequencing analysis. They were compared with the sequences registered in GenBank. It was confirmed that most specimens were likely from African forest elephants (Loxodonta cyclotis), one from African savanna elephant (Loxodonta africana) and one from Asian elephant (Elephas maximus). Analysis of the mitochondrial hypervariable D-loop region sequence of elephants verified that one African savanna elephant might be from South Africa and one Asian elephant from Laos. Cytochrome b and D-loop region located in the mitochondrial DNA resulted in the successful determination of elephant DNA from nine processed ivory specimens. PMID:23472798

  20. Nondestructive discrimination of ivories and prediction of their specific gravity by Fourier-transform Raman spectroscopy and chemometrics.

    PubMed

    Shimoyama, Masahiko; Ninomiya, Toshio; Ozaki, Yukihiro

    2003-07-01

    Fourier-transform (FF) Raman spectroscopy and chemometrics were used for nondestructive analysis of ivories. The discrimination of five kinds of ivories, two subspecies of African elephant, mammoth, hippopotamus, and sperm whale, was investigated, and a calibration model for predicting their specific gravity was developed. FT-Raman spectra were measured in situ for them and chemometrics analyses were carried out for the 3050-350 cm(-1) region. The five kinds of ivories were clearly discriminated from each other on the scores plots of two or three principal components (PCs) obtained by principal component analysis (PCA). The loadings plot for PC 1 shows that the discrimination relies on the content ratio of organic collagenous protein and inorganic hydroxyapatite of ivories. The loadings plot for PC 2 shows that bands due to the CH3 and CH2 stretching modes of the protein also play a role in the discrimination. Using partial least squares regression (PLSR), we developed a calibration model that predicts the specific gravity of the ivories from the FT-Raman spectra. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.980 and 0.024, respectively. PMID:12894836

  1. Levels and trends of organochlorines and brominated flame retardants in ivory gull eggs from the Canadian Arctic, 1976 to 2004.

    PubMed

    Braune, Birgit M; Mallory, Mark L; Grant Gilchrist, H; Letcher, Robert J; Drouillard, Ken G

    2007-06-01

    The ivory gull (Pagophila eburnea) is a circumpolar marine bird which has recently been listed as an endangered species in Canada. To determine whether contaminants may be playing a role in the population decline of this species, ivory gull eggs collected in 1976, 1987 and 2004 from Seymour Island in the Canadian Arctic were analyzed for organochlorines, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and non-ortho PCBs. This study also provides the first account of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and polybrominated biphenyls (PBBs) in ivory gulls. The most quantitatively abundant legacy organochlorines found in the ivory gull eggs were p,p'-DDE, SigmaPCB and oxychlordane. Concentrations of the organochlorines analyzed either decreased or showed little change between 1976 and 2004. Concentrations of SigmaPCDD in ivory gull eggs were greater than SigmaPCDF, and the non-ortho PCBs (primarily PCB-126) contributed the largest fraction to the total TEQ value in all years sampled. Concentrations of PCDDs, PCDFs and SigmaTEQ decreased from 1976 to 2004. In contrast, concentrations of the PBDEs steadily increased between 1976 and 2004 driven primarily by increases in BDE-47. Although concentrations of the persistent chlorinated compounds (i.e. organochlorine pesticides, PCBs, PCDDs, PCDFs) reported in this study were below published toxicological threshold values for eggs of wild birds, we cannot rule out the possibility of synergistic/additive, sublethal effects. Very few studies have been carried out to evaluate the exposure-effect relationship of the persistent brominated compounds in avian species. Given the scarcity of information on toxicity threshold levels for PBBs and PBDEs in avian species, coupled with the trend toward increasing concentrations in ivory gulls, continued monitoring and further toxicological studies of these compounds are warranted. PMID:17412396

  2. Parametric study of the impact of waste pollutants on groundwater: the case of Abidjan District (Ivory Coast)

    NASA Astrophysics Data System (ADS)

    Agnès Kouamé, Amenan; Jaboyedoff, Michel; Tacher, Laurent; Derron, Marc-Henri; Franz, Martin

    2015-04-01

    Abidjan like numerous African cities is experiencing a significant and uncontrolled population growth. The annual growth rate is estimated at 3.99% by the National Institute of Statistics. This rapid population growth also generates growing needs in general and especially for drinking water and economic activities. In the District of Abidjan, groundwater comes from the Mio-Pliocene age aquifer called "Continental Terminal". This unconfined aquifer is the main source of water supply. Its lithology consists of four levels. Actually only the two upper levels outcrop and constitute the main part of the Continental Terminal aquifer. Some recent studies report a potential overexploitation and pollution of Abidjan groundwater (Jourda, 1986, Kouame 2007, Deh, 2013). This deterioration in water quality could be due to the release of domestic and industrial waste water, pesticide and fertilizer from crops and toxic waste sites containing high doses of organochlorines, of hydrogen sulfide and sulfides. This risk is also linked to the economic activities such as car workshops, gas stations and the sand exploitation in the lagoon. To observe the likely evolution of such contaminants in the subsurface and we developed hydrogeological models that couple groundwater flow and transport with FEFLOW software. The model is composed of a sandy layer where two constant hydraulic heads of 55 m and 0.2 m are imposed on the north and the south respectively. We carried out grain size analysis of some samples (E2, E3, E4, E5, and E6) which shows particle size ranging between 0.0001 mm and 8 mm. This grain size analysis performed by sieving underwater and laser indicates that these five soils are: loamy sand with traces of clay and gravel for E2 and E5; Sandy loam with traces of clay for E3; Sand with traces of clay and gravel for E4 and Sand with traces of silt and clay for E6. Their porosity and average values of permeability coefficient K measured in the laboratory range from 0.2 to 0.4 and 2.9E-8 and 2.48E-5 m/s, respectively. These values of permeability are low. They were therefore multiplied by 10 in order to calibrate the model. This suggests that the environment of deposition of the sands is heterogeneous with coarse sand channels in places as it can be expected in such lagoon environment. The result of the model simulation in steady state indicates the groundwater flow direction (North-South) and the approach of pollutants plumes to some well fields after 20 years. References: Deh S. K. (2013). Contributions de l'évaluation de la vulnérabilité spécifique aux nitrates et d'un modèle de transport des organochlorés a la protection des eaux souterraines du district d'Abidjan (sud de la Côte d'Ivoire) 230p. Jourda J. P. (1987). Contribution à l'étude géologique et hydrogéologique de la région du Grand Abidjan (Côte d'Ivoire). Thèse de doctorat de 3ème cycle, Université scientifique, technique et médicale de Grenoble, 319p. Kouamé K. J. (2007). Contribution à la Gestion Intégrée des Ressources en Eaux (GIRE) du District d'Abidjan (Sud de la Côte d'Ivoire) : Outils d'aide à la décision pour la prévention et la protection des eaux souterraines contre la pollution, Thèse de doctorat unique de l'Université de Cocody, 229p.

  3. Genital ulcers associated with human immunodeficiency virus-related immunosuppression in female sex workers in Abidjan, Ivory Coast.

    PubMed

    Ghys, P D; Diallo, M O; Ettigne-Traor, V; Yebou, K M; Gnaor, E; Lorougnon, F; Kal, K; Van Dyck, E; Brettegaard, K; Hoyi, Y M

    1995-11-01

    A cross-sectional study among female sex workers in Abidjan was conducted to study the association between sexually transmitted diseases and human immunodeficiency virus (HIV) infection and HIV-related immunosuppression. Among 1209 women tested for HIV, 962 (80%) were seropositive. HIV infection was independently associated with a longer duration of sex work, a lower price for intercourse, being an immigrant, and having a positive Treponema pallidum hemagglutination test (P < .05). Genital ulcers (25% vs. 5%), genital warts (14% vs. 4%), Neisseria gonorrhoeae (32% vs. 16%), Trichomonas vaginalis (27% vs. 17%), and syphilis (27% vs. 17%) were more frequent (P < .05) in HIV-infected than -uninfected women. Among HIV-infected women, the proportions with a genital ulcer were 17%, 25%, and 36% for those with > 28%, 14%-28%, and < 14% CD4 cells, respectively (P < .001). This study suggests that genital ulcers are an opportunistic disease in female sex workers in Abidjan. PMID:7594681

  4. [Use of a questionnaire for quick identification of the principal foci of urinary bilharziasis in central Ivory Coast].

    PubMed

    N'Goran, E K; Utzinger, J; Traore, M; Lengeler, C; Tanner, M

    1998-01-01

    Simple questionnaires designed for use in schools have been used to identify communities at high risk for urinary schistosomiasis in several African countries but not in the Cote d'Ivoire. The primary purpose of this study was to assess the acceptance and feasibility of the school questionnaire approach in the Cote d'Ivoire. Questionnaires were distributed to 136 schools in central Cote d'Ivoire. Responses were obtained within 6 weeks from 124 schools (91.2%). A total of 12,479 school children were interviewed. At 60 schools, reagent stick tests were performed within two weeks to detect microhematuria by trained teachers. A biomedical team was sent to 14 selected schools to check results by reagent stick testing and urine filtration. Reagent stick tests showed high specificity (97%) and moderate sensitivity (67%). A strong statistical correlation was observed between responses to two key questions concerning "blood in urine" and "having had schistosomiasis" and the results of reagent stick testing (Spearman rank correlation, p < 0.0001). Our findings are in good agreement with previous reports. Using the data obtained, we were able to accurately map the distribution of urinary schistosomiasis in the study area. Use of this questionnaire for quick identification of high risk communities for urinary schistosomiasis was recommended as a preliminary step in the planned national control program and should allow better targeted of scarce resources. PMID:10088102

  5. [Mediastino-pulmonary sarcoidosis in Ivory Coast. Epidemiological and clinical significance of sixteen new cases observed in Abidjan (author's transl)].

    PubMed

    Roudaut, M; Tiendrebeogo, H; Pigearias, B; Rain, B; Schmidt, D; Coulibaly, N; Delormas, P

    1980-01-01

    Sixteen cases of mediastion-pulmonary sarcoïdosis are reported, half of them presenting extra-thoracic associated lesions. The clinical and epidemiological study of these cases, compared to the previously published ones, demonstrates that the clinical features are similar in Africans and Black Americans and that the disease in coming out in Africa South of the Sahara. PMID:6247599

  6. CONSERVATION. Genetic assignment of large seizures of elephant ivory reveals Africa's major poaching hotspots.

    PubMed

    Wasser, S K; Brown, L; Mailand, C; Mondol, S; Clark, W; Laurie, C; Weir, B S

    2015-07-01

    Poaching of elephants is now occurring at rates that threaten African populations with extinction. Identifying the number and location of Africa's major poaching hotspots may assist efforts to end poaching and facilitate recovery of elephant populations. We genetically assign origin to 28 large ivory seizures (≥0.5 metric tons) made between 1996 and 2014, also testing assignment accuracy. Results suggest that the major poaching hotspots in Africa may be currently concentrated in as few as two areas. Increasing law enforcement in these two hotspots could help curtail future elephant losses across Africa and disrupt this organized transnational crime. PMID:26089357

  7. Intrinsic oxygen fugacity measurements on seven chondrites, a pallasite, and a tektite and the redox state of meteorite parent bodies

    USGS Publications Warehouse

    Brett, R.; Sato, M.

    1984-01-01

    Intrinsic oxygen-fugacity (fO2) measurements were made on five ordinary chondrites, a carbonaceous chondrite, an enstatite chondrite, a pallasite, and a tektite. Results are of the form of linear log fO2 - 1 T plots. Except for the enstatite chondrite, measured results agree well with calculated estimates by others. The tektite produced fO2 values well below the range measured for terrestrial and lunar rocks. The lowpressure atmospheric regime that is reported to follow large terrestrial explosions, coupled with a very high temperature, could produce glass with fO2 in the range measured. The meteorite Salta (pallasite) has low fO2 and lies close to Hvittis (E6). Unlike the other samples, results for Salta do not parallel the iron-wu??stite buffer, but are close to the fayalite-quartz-iron buffer in slope. Minor reduction by graphite appears to have taken place during metamorphism of ordinary chondrites. fO2 values of unequilibrated chondrites show large scatter during early heating suggesting that the constituent phases were exposed to a range of fO2 conditions. The samples equilibrated with respect to fO2 in relatively short time on heating. Equilibration with respect to fO2 in ordinary chondrites takes place between grades 3 and 4 of metamorphism. Application of P - T - fO2 relations in the system C-CO-CO2 indicates that the ordinary chondrites were metamorphosed at pressures of 3-20 bars, as it appears that they lay on the graphite surface. A steep positive thermal gradient in a meteorite parent body lying at the graphite surface will produce thin reduced exterior, an oxidized near-surface layer, and an interior that is increasingly reduced with depth; a shallow thermal gradient will produce the reverse. A body heated by accretion on the outside will have a reduced exterior and oxidized interior. Meteorites from the same parent body clearly are not required to have similar redox states. ?? 1984.

  8. Non-destructive analysis of the two subspecies of African elephants, mammoth, hippopotamus, and sperm whale ivories by visible and short-wave near infrared spectroscopy and chemometrics.

    PubMed

    Shimoyama, Masahiko; Morimoto, Susumu; Ozaki, Yukihiro

    2004-06-01

    Visible (VIS) and short-wave near infrared (SW-NIR) spectroscopy was used for non-destructive analysis of ivories. VIS-SW-NIR (500-1000 nm) spectra were measured in situ for five kinds of ivories, that is two subspecies of African elephants, mammoth, hippopotamus, and sperm whale. Chemometrics analyses were carried out for the spectral data from 500 to 1000 nm region. The five kinds of ivories were clearly discriminated from each other on the scores plot of two principal components (PCs) obtained by principal component analysis (PCA). It was noteworthy that the ivories of the two subspecies of African elephants were discriminated by the scores of PC 1. The loadings plot for PC 1 showed that the discrimination relies on the intensity changes in bands due to collagenous proteins and water interacting with proteins. It was found that the scores plot of PC 2 is useful to distinguish between the ivories of the two subspecies of African elephants and the other ivories. We also developed a calibration model that predicted the specific gravity of five kinds of ivories from their VIS-SW-NIR spectral data using partial least squares (PLS)-1 regression. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.960 and 0.037, respectively. PMID:15152335

  9. Assigning African elephant DNA to geographic region of origin: Applications to the ivory trade

    PubMed Central

    Wasser, Samuel K.; Shedlock, Andrew M.; Comstock, Kenine; Ostrander, Elaine A.; Mutayoba, Benezeth; Stephens, Matthew

    2004-01-01

    Resurgence of illicit trade in African elephant ivory is placing the elephant at renewed risk. Regulation of this trade could be vastly improved by the ability to verify the geographic origin of tusks. We address this need by developing a combined genetic and statistical method to determine the origin of poached ivory. Our statistical approach exploits a smoothing method to estimate geographic-specific allele frequencies over the entire African elephants' range for 16 microsatellite loci, using 315 tissue and 84 scat samples from forest (Loxodonta africana cyclotis) and savannah (Loxodonta africana africana) elephants at 28 locations. These geographic-specific allele frequency estimates are used to infer the geographic origin of DNA samples, such as could be obtained from tusks of unknown origin. We demonstrate that our method alleviates several problems associated with standard assignment methods in this context, and the absolute accuracy of our method is high. Continent-wide, 50% of samples were located within 500 km, and 80% within 932 km of their actual place of origin. Accuracy varied by region (median accuracies: West Africa, 135 km; Central Savannah, 286 km; Central Forest, 411 km; South, 535 km; and East, 697 km). In some cases, allele frequencies vary considerably over small geographic regions, making much finer discriminations possible and suggesting that resolution could be further improved by collection of samples from locations not represented in our study. PMID:15459317

  10. Circumpolar contamination in eggs of the high-Arctic ivory gull Pagophila eburnea.

    PubMed

    Lucia, Magali; Verboven, Nanette; Strøm, Hallvard; Miljeteig, Cecilie; Gavrilo, Maria V; Braune, Birgit M; Boertmann, David; Gabrielsen, Geir W

    2015-07-01

    The ivory gull Pagophila eburnea is a high-Arctic species threatened by climate change and contaminants. The objective of the present study was to assess spatial variation of contaminant levels (organochlorines [OCs], brominated flame retardants [BFRs], perfluorinated alkyl substances [PFASs], and mercury [Hg]) in ivory gulls breeding in different areas across the Arctic region as a baseline for potential future changes associated with climate change. Contaminants were already determined in eggs from Canada (Seymour Island; except PFASs), Svalbard in Norway (Svenskøya), and 3 sites in Russia (Nagurskoe, Cape Klyuv, and Domashny). New data from Greenland allowed the investigation of a possible longitudinal gradient of contamination. The most quantitatively abundant OCs were p,p'-dichlorodiphenyldichloroethylene (DDE) and polychlorobiphenyls. Mercury concentrations were higher in Canada compared with other colonies. Eggs from Nagurskoe often were characterized by higher OC and BFR concentrations. Concentrations gradually decreased in colonies situated east of Nagurskoe. In contrast, PFAS concentrations, especially perfluorooctanoate and perfluorononanoate, were higher in Greenland. Some of the contaminants, especially Hg and p,p'-DDE, exceeded published thresholds known to disrupt the reproductive success of avian species. Overall, the levels of OCs, BFRs, and PFASs did not suggest direct lethal exposure to these compounds, but their potential synergetic/additive sublethal effects warrant monitoring. PMID:25677940

  11. The Case of the Ivory-Billed Woodpecker: The Scientific Process and How It Relates to Everyday Life

    ERIC Educational Resources Information Center

    Stanger-Hall, Kathrin; Merriam, Jennifer; Greuling, Ruth Ann

    2007-01-01

    In this case study, based on the reported rediscovery of the Ivory-billed Woodpecker in April 2005, students examine a real-world example of the scientific process and explore the practical implications of their conclusions. The case tells the story of Brad Murky, a student and research assistant who must decide whether the available evidence is…

  12. The Case of the Ivory-Billed Woodpecker: The Scientific Process and How It Relates to Everyday Life

    ERIC Educational Resources Information Center

    Stanger-Hall, Kathrin; Merriam, Jennifer; Greuling, Ruth Ann

    2007-01-01

    In this case study, based on the reported rediscovery of the Ivory-billed Woodpecker in April 2005, students examine a real-world example of the scientific process and explore the practical implications of their conclusions. The case tells the story of Brad Murky, a student and research assistant who must decide whether the available evidence is

  13. How Much Ivory Does This Tower Need? What We Spend on, and Get from, Higher Education. Policy Analysis. No. 686

    ERIC Educational Resources Information Center

    McCluskey, Neal

    2011-01-01

    It is commonly asserted, especially by people within higher education, that the American Ivory Tower is strapped for cash and tightfisted taxpayers are to blame. Taxpayer support for postsecondary education has long been in decline, this narrative goes, and has forced schools to continually raise tuition to make up for the losses. Tallying

  14. Eggshell thinning and decreased concentrations of vitamin E are associated with contaminants in eggs of ivory gulls.

    PubMed

    Miljeteig, Cecilie; Gabrielsen, Geir Wing; Strm, Hallvard; Gavrilo, Maria V; Lie, Elisabeth; Jenssen, Bjrn Munro

    2012-08-01

    The ivory gull is a high Arctic seabird species threatened by climate change and contaminant exposure. High levels of contaminants have been reported in ivory gull Pagophila eburnea eggs from Svalbard and the Russian Arctic. The present study investigated associations between high levels of contaminants (organochlorinated pesticides (OCPs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs), perfluorinated alkyl substances (PFASs) and mercury (Hg)) and three response variables: eggshell thickness, retinol (vitamin A) and ?-tocopherol (vitamin E). Negative associations were found between levels of OCPs, PCBs and BFRs and eggshell thickness (p<0.021) and ?-tocopherol (p<0.023), but not with retinol (p>0.1). There were no associations between PFASs and mercury and the three response variables. Furthermore, the eggshell thickness was 7-17% thinner in the present study than in archived ivory gull eggs (?1930). In general, a thinning above 16 to 20% has been associated with a decline in bird populations, suggesting that contaminant-induced eggshell thinning may constitute a serious threat to ivory gull populations globally. PMID:22673175

  15. Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico

    NASA Technical Reports Server (NTRS)

    Smit, J.; Montanari, A.; Swinburne, N. H.; Alvarez, W.; Hildebrand, A. R.; Margolis, S. V.; Claeys, P.; Lowrie, W.; Asaro, F.

    1992-01-01

    The hypothesis of Cretaceous-Tertiary (K-T) boundary impact on Yucatan, Mexico, predicts that nearby sites should show evidence of proximal impact ejecta and disturbance by giant waves. An outcrop along the Arroyo el Mimbral in northeastern Mexico contains a layered clastic unit up to 3 m thick that interrupts a biostratigraphically complete pelagic-marl sequence deposited at more than 400 m water depth. The marls were found to be unsuitable for determining magnetostratigraphy, but foraminiferal biostratigraphy places the clastic unit precisely at the K-T boundary. We interpret this clastic unit as the deposit of a megawave or tsunami produced by an extraterrestrial impact. The clastic unit comprises three main subunits. (1) The basal "spherule bed" contains glass in the form of tektites and microtektites, glass spherules replaced by chlorite-smectite and calcite, and quartz grains showing probable shock features. This bed is interpreted as a channelized deposit of proximal ejecta. (2) A set of lenticular, massive, graded "laminated beds" contains intraclasts and abundant plant debris, and may be the result of megawave backwash that carried coarse debris from shallow parts of the continental margin into deeper water. (3) At the top, several thin "ripple beds" composed of fine sand are separated by clay drapes; they are interpreted as deposits of oscillating currents, perhaps a seiche. An iridium anomaly (921 +/- 23 pg/g) is observed at the top of the ripple beds. Our observations at the Mimbral locality support the hypothesis of a K-T impact on nearby Yucatan.

  16. Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico

    SciTech Connect

    Smit, J. ); Montanari, A.; Swinburne, N.H.M.; Alvarez, W. ); Hildebrand, A.R. ); Margolis, S.V.; Claeys, P. ); Lowrie, W. ); Asaro, F. )

    1992-02-01

    The hypothesis of Cretaceous-Tertiary (K-T) boundary impact on Yucatan, Mexico, predicts that nearby sites should show evidence of proximal impact ejecta and disturbance by giant waves. An outcrop along the Arroyo el Mimbral in northeastern Mexico contains a layered clastic unit up to 3 m thick that interrupts a biostratigraphically complete pelagic-marl sequence deposited at more than 400 m water depth. The marls were found to be unsuitable for determining magnetostratigraphy, but foraminiferal biostratigraphy places the clastic unit precisely at the K-T boundary. The authors interpret this clastic unit as the deposit of a megawave or tsunami produced by an extraterrestrial impact. The clastic unit comprises three main subunits. (1) The basal 'spherule bed' contains glass in the form of tektites and microtektites, glass spherules replaced by chlorite-smectite and calcite, and quartz grains showing probable shock features. This bed is interpreted as a channelized deposit of proximal ejecta. (2) A set of lenticular, massive, graded 'laminated beds' contains intraclasts can abundant plant debris, and may the result of megawave backwash that carried coarse debris from shallow parts of the continental margin into deeper water. (3) At the top, several thin 'ripple beds' composed of fine sand are separated by clay drapes; they are interpreted as deposits of oscillating currents, perhaps a seiche. An iridium anomaly (921 {plus minus} 23 pg/g) is observed at the top of the ripple beds. Their observations at the Mimbral locality support the hypothesis of a K-T impact on nearby Yucatan.

  17. Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico.

    PubMed

    Smit, J; Montanari, A; Swinburne, N H; Alvarez, W; Hildebrand, A R; Margolis, S V; Claeys, P; Lowrie, W; Asaro, F

    1992-02-01

    The hypothesis of Cretaceous-Tertiary (K-T) boundary impact on Yucatn, Mexico, predicts that nearby sites should show evidence of proximal impact ejecta and disturbance by giant waves. An outcrop along the Arroyo el Mimbral in northeastern Mexico contains a layered clastic unit up to 3 m thick that interrupts a biostratigraphically complete pelagic-marl sequence deposited at more than 400 m water depth. The marls were found to be unsuitable for determining magnetostratigraphy, but foraminiferal biostratigraphy places the clastic unit precisely at the K-T boundary. We interpret this clastic unit as the deposit of a megawave or tsunami produced by an extraterrestrial impact. The clastic unit comprises three main subunits. (1) The basal "spherule bed" contains glass in the form of tektites and microtektites, glass spherules replaced by chlorite-smectite and calcite, and quartz grains showing probable shock features. This bed is interpreted as a channelized deposit of proximal ejecta. (2) A set of lenticular, massive, graded "laminated beds" contains intraclasts and abundant plant debris, and may be the result of megawave backwash that carried coarse debris from shallow parts of the continental margin into deeper water. (3) At the top, several thin "ripple beds" composed of fine sand are separated by clay drapes; they are interpreted as deposits of oscillating currents, perhaps a seiche. An iridium anomaly (921 +/- 23 pg/g) is observed at the top of the ripple beds. Our observations at the Mimbral locality support the hypothesis of a K-T impact on nearby Yucatn. PMID:11537752

  18. Specimen-based modeling, stopping rules, and the extinction of the Ivory-billed Woodpecker.

    PubMed

    Gotelli, Nicholas J; Chao, Anne; Colwell, Robert K; Hwang, Wen-Han; Graves, Gary R

    2012-02-01

    Assessing species survival status is an essential component of conservation programs. We devised a new statistical method for estimating the probability of species persistence from the temporal sequence of collection dates of museum specimens. To complement this approach, we developed quantitative stopping rules for terminating the search for missing or allegedly extinct species. These stopping rules are based on survey data for counts of co-occurring species that are encountered in the search for a target species. We illustrate both these methods with a case study of the Ivory-billed Woodpecker (Campephilus principalis), long assumed to have become extinct in the United States in the 1950s, but reportedly rediscovered in 2004. We analyzed the temporal pattern of the collection dates of 239 geo-referenced museum specimens collected throughout the southeastern United States from 1853 to 1932 and estimated the probability of persistence in 2011 as <6.4 10(-5) , with a probable extinction date no later than 1980. From an analysis of avian census data (counts of individuals) at 4 sites where searches for the woodpecker were conducted since 2004, we estimated that at most 1-3 undetected species may remain in 3 sites (one each in Louisiana, Mississippi, Florida). At a fourth site on the Congaree River (South Carolina), no singletons (species represented by one observation) remained after 15,500 counts of individual birds, indicating that the number of species already recorded (56) is unlikely to increase with additional survey effort. Collectively, these results suggest there is virtually no chance the Ivory-billed Woodpecker is currently extant within its historical range in the southeastern United States. The results also suggest conservation resources devoted to its rediscovery and recovery could be better allocated to other species. The methods we describe for estimating species extinction dates and the probability of persistence are generally applicable to other species for which sufficient museum collections and field census results are available. PMID:21797923

  19. Coeval Ar-40/Ar-39 ages of 65.0 million years ago from Chicxulub crater melt rock and Cretaceous-Tertiary boundary tektites

    NASA Technical Reports Server (NTRS)

    Swisher, Carl C., III; Grajales-Nishimura, Jose M.; Montanari, Alessandro; Margolis, Stanley V.; Claeys, Philippe; Alvarez, Walter; Renne, Paul; Cedillo-Pardo, Esteban; Maurrasse, Florentin J.-M. R.; Curtis, Garniss H.

    1992-01-01

    Ar-40/Ar-39 dating of drill-core samples of a glassy melt rock recovered from beneath a massive impact breccia contained with the 180-kilometer subsurface Chicxulub crater yields well-behaved incremental heating spectra with a mean plateau age of 64.98 +/- 0.05 million years ago (Ma). The glassy melt rock of andesitic composition was obtained from core 9 (1390 to 1393 meters) in the Chicxulub 1 well. The age of the melt rock is virtually indistinguishable from Ar-40/Ar-39 ages obtained on tektite glass from Beloc, Haiti, and Arroyo el Mimbral, northeastern Mexico, of 65.01 +/- 0.08 Ma (mean plateau age for Beloc) and 65.07 +/- 0.10 Ma (mean total fusion age for both sites). The Ar-40/Ar-39 ages, in conjunction with geochemical and petrological similarities, strengthen the suggestion that the Chicxulub structure is the source for the Haitian and Mexican tektites and is a viable candidate for the Cretaceous-Tertiary boundary impact site.

  20. Coeval 40Ar/39Ar Ages of 65.0 Million Years Ago from Chicxulub Crater Melt Rock and Cretaceous-Tertiary Boundary Tektites.

    PubMed

    Swisher, C C; Grajales-Nishimura, J M; Montanari, A; Margolis, S V; Claeys, P; Alvarez, W; Renne, P; Cedillo-Pardoa, E; Maurrasse, F J; Curtis, G H; Smit, J; McWilliams, M O

    1992-08-14

    (40)Ar/(39)Ar dating of drill core samples of a glassy melt rock recovered from beneath a massive impact breccia contained within the 180-kilometer subsurface Chicxulub crater in Yucatn, Mexico, has yielded well-behaved incremental heating spectra with a mean plateau age of 64.98 +/- 0.05 million years ago (Ma). The glassy melt rock of andesitic composition was obtained from core 9 (1390 to 1393 meters) in the Chicxulub 1 well. The age of the melt rock is virtually indistinguishable from (40)Ar/(39)Ar ages obtained on tektite glass from Beloc, Haiti, and Arroyo el Mimbral, northeastern Mexico, of 65.01 +/- 0.08 Ma (mean plateau age for Beloc) and 65.07 +/- 0.10 Ma (mean total fusion age for both sites). The (40)Ar/(39)Ar ages, in conjunction with geochemical and petrological similarities, strengthen the recent suggestion that the Chicxulub structure is the source for the Haitian and Mexican tektites and is a viable candidate for the Cretaceous-Tertiary boundary impact site. PMID:17789640

  1. Scientists Explore Alaska's Coast

    USGS Multimedia Gallery

    This oblique aerial photograph is of Flaxman Island off the Alaska coast and shows a tapped thermokarst lakes, caribou tracks and ice-rich bluffs that are eroding. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important f...

  2. Scientists Explore Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows snow and ice melt along the rolling hills and coastal bluffs near Cape Sabine on the western Chukchi Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energ...

  3. Caribou Along Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows three caribou escape the mosquitos on the mudflats of Kasegaluk Lagoon on the Chukchi Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, nat...

  4. California Coast Seafloor

    USGS Multimedia Gallery

    Photograph showing the seafloor off the California coast. This photograph supports the California Seafloor Mapping Program (CSMP), which was initiated in 2007 by the California Ocean Protection Council. Data collected during this project reveal the seafloor offshore of the California coast in unprec...

  5. The retrieval of fingerprint friction ridge detail from elephant ivory using reduced-scale magnetic and non-magnetic powdering materials.

    PubMed

    Weston-Ford, Kelly A; Moseley, Mark L; Hall, Lisa J; Marsh, Nicholas P; Morgan, Ruth M; Barron, Leon P

    2016-01-01

    An evaluation of reduced-size particle powdering methods for the recovery of usable fingermark ridge detail from elephant ivory is presented herein for the first time as a practical and cost-effective tool in forensic analysis. Of two reduced-size powder material types tested, powders with particle sizes?40?m offered better chances of recovering ridge detail from unpolished ivory in comparison to a conventional powder material. The quality of developed ridge detail of these powders was also assessed for comparison and automated search suitability. Powder materials and the enhanced ridge detail on ivory were analysed by scanning electron microscopy and energy dispersive X-ray spectroscopy and interactions between their constituents and the ivory discussed. The effect of ageing on the quality of ridge detail recovered showed that the best quality was obtained within 1week. However, some ridge detail could still be developed up to 28days after deposition. Cyanoacrylate and fluorescently-labelled cyanoacrylate fuming of ridge detail on ivory was explored and was less effective than reduced-scale powdering in general. This research contributes to the understanding and potential application of smaller scale powdering materials for the development of ridge detail on hard, semi-porous biological material typically seized in wildlife-related crimes. PMID:26746820

  6. Phagocytosis and respiratory burst activity of haemocytes from the ivory snail, Babylonia areolata.

    PubMed

    Di, Guilan; Zhang, Zhaoxia; Ke, Caihuan

    2013-08-01

    Haemocytes from the ivory snail, Babylonia areolata phagocytized Saccharomyces cerevisiae and Vibrio parahaemolyticus after 30 min. Haemocytes phagocytized V. parahaemolyticus at a greater rate than they phagocytized S. cerevisiae. The phagocytic rate (PP) of V. parahaemolyticus by granulocytes to was a little higher than that of S. cerevisiae. The phagocytic index (PI) of V. parahaemolyticus by granulocytes was significantly higher than that of S. cerevisiae. The same was true of hyalinocytes. The PP of granulocytes was significantly higher than that of hyalinocytes for each pathogen. No difference in PI was observed in granulocytes and hyalinocytes. Two defense mechanisms of B. areolata were quantified using flow cytometry. Haemocyte phagocytosis was quantified using fluorescent microbeads and respiratory burst activity was measured using H2O2 increases detected by 2', 7'-dichlorofluorescein diacetate. Both phagocytosis and respiratory burst activity of the haemocytes increased over time. After 90 min the phagocytic rate no longer increased. In the case of respiratory burst, the greatest increase in fluorescence occurred between 30 and 120 min, no further increase was seen after 120 min. These results showed unequivocally that a native (unstimulated) haemocyte oxidative burst was active in B. areolata. The aim of this study was to further the knowledge of immunology in gastropods. PMID:23664911

  7. African elephants show high levels of interest in the skulls and ivory of their own species.

    PubMed

    McComb, Karen; Baker, Lucy; Moss, Cynthia

    2006-03-22

    An important area of biology involves investigating the origins in animals of traits that are thought of as uniquely human. One way that humans appear unique is in the importance they attach to the dead bodies of other humans, particularly those of their close kin, and the rituals that they have developed for burying them. In contrast, most animals appear to show only limited interest in the carcasses or associated remains of dead individuals of their own species. African elephants (Loxodonta africana) are unusual in that they not only give dramatic reactions to the dead bodies of other elephants, but are also reported to systematically investigate elephant bones and tusks that they encounter, and it has sometimes been suggested that they visit the bones of relatives. Here, we use systematic presentations of object arrays to demonstrate that African elephants show higher levels of interest in elephant skulls and ivory than in natural objects or the skulls of other large terrestrial mammals. However, they do not appear to specifically select the skulls of their own relatives for investigation so that visits to dead relatives probably result from a more general attraction to elephant remains. PMID:17148317

  8. African elephants show high levels of interest in the skulls and ivory of their own species

    PubMed Central

    McComb, Karen; Baker, Lucy; Moss, Cynthia

    2005-01-01

    An important area of biology involves investigating the origins in animals of traits that are thought of as uniquely human. One way that humans appear unique is in the importance they attach to the dead bodies of other humans, particularly those of their close kin, and the rituals that they have developed for burying them. In contrast, most animals appear to show only limited interest in the carcasses or associated remains of dead individuals of their own species. African elephants (Loxodonta africana) are unusual in that they not only give dramatic reactions to the dead bodies of other elephants, but are also reported to systematically investigate elephant bones and tusks that they encounter, and it has sometimes been suggested that they visit the bones of relatives. Here, we use systematic presentations of object arrays to demonstrate that African elephants show higher levels of interest in elephant skulls and ivory than in natural objects or the skulls of other large terrestrial mammals. However, they do not appear to specifically select the skulls of their own relatives for investigation so that visits to dead relatives probably result from a more general attraction to elephant remains. PMID:17148317

  9. Mapping Potential Ivory Billed Woodpecker Habitat using Lidar and Hyperspectral Data Fusion

    NASA Astrophysics Data System (ADS)

    Swatantran, A.; Dubayah, R.; Hofton, M.; Blair, J. B.; Handley, L.

    2008-12-01

    Multisensor fusion is a powerful approach towards characterizing forest structure for effective management of wildlife habitats. The rediscovery of the Ivory Billed Woodpecker in 2005 reinforced the need to map and conserve suitable habitat for the previously thought extinct bird. In this study we fused waveform lidar and hyperspectral data to map potential habitat for the woodpecker along the Lower Mississippi Valley of Arkansas. Laser Vegetation Imaging Sensor (LVIS) data was processed to produce high-resolution forest structure maps. We used multiple endmember spectral mixture analysis (MESMA) to map stressed and dead vegetation from the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data. LVIS and AVIRIS maps were fused to identify habitat hot-spots based on historical records of habitat preferences of the bird. Results indicate several small hotspots in the bottomland hardwood forests, but very few large and continuous patches qualify as potential woodpecker habitat. Results from this study are expected to aid search efforts for the woodpecker and also provide useful insights into lidar fusion for large scale habitat mapping.

  10. Gulf Coast Wetlands

    Atmospheric Science Data Center

    2014-05-15

    article title:  Wetlands of the Gulf Coast     View Larger Image ... SpectroRadiometer (MISR) highlights coastal areas of four states along the Gulf of Mexico: Louisiana, Mississippi, Alabama and part of ...

  11. Tektite Suborbital Science

    NASA Astrophysics Data System (ADS)

    Harris, T. H. S.

    2015-07-01

    The australite fall sites in S. Australia at 10 km/s require loft times of 7.5 hrs from Indochina and 112.5 deg Earth spin, inconsistent with a launch from that same hemisphere. Alternative AA source regions must explain these imprint elements.

  12. South Oregon Coast Reinforcement.

    SciTech Connect

    United States. Bonneville Power Administration.

    1998-05-01

    The Bonneville Power Administration is proposing to build a transmission line to reinforce electrical service to the southern coast of Oregon. This FYI outlines the proposal, tells how one can learn more, and how one can share ideas and opinions. The project will reinforce Oregon`s south coast area and provide the necessary transmission for Nucor Corporation to build a new steel mill in the Coos Bay/North Bend area. The proposed plant, which would use mostly recycled scrap metal, would produce rolled steel products. The plant would require a large amount of electrical power to run the furnace used in its steel-making process. In addition to the potential steel mill, electrical loads in the south Oregon coast area are expected to continue to grow.

  13. Impact of Tributyltin and Triphenyltin on Ivory Shell (Babylonia japonica) Populations

    PubMed Central

    Horiguchi, Toshihiro; Kojima, Mitsuhiro; Hamada, Fumihiko; Kajikawa, Akira; Shiraishi, Hiroaki; Morita, Masatoshi; Shimizu, Makoto

    2006-01-01

    We histopathologically examined gonads and chemically determined organotin compounds in tissues of the ivory shell, Babylonia japonica. Imposex (a superimposition of male-type genital organs on females) occurred in approximately 8090% of B. japonica specimens that we examined, with the penis and vas deferens both well developed. No oviduct blockage by vas deferens formation was observed. Ovarian spermatogenesis and suppressed ovarian maturation were observed in the females that exhibited imposex, although no histopathological abnormalities were found in males. Tissue distributions of organotin compounds [tributyltin (TBT), triphenyltin (TPhT), and their metabolites] were different for butyltins and phenyltins; a remarkably high accumulation of TBT was observed in the ctenidium, osphradium, and heart, whereas high concentrations of TPhT were detected in the ovary and digestive gland. More than one-third of TBT accumulated in the digestive glands of both males and females, followed by the testis, ctenidium, muscle, and heart tissues in males and in the muscle, ovary, ctenidium, and head tissues (including the central nervous system ganglia) in females. In both males and females, more than half of total TPhT accumulated in the digestive glands, followed by the gonads. The next highest values were in the muscle, ctenidium, and heart tissues in males and in the muscle, oviduct, and head tissues in females. Both TBT and TPhT concentrations in the gonads were positively correlated with penis length in females. Our findings strongly suggest that reproductive failure in adult females accompanied by imposex, possibly induced by TBT and TPhT from antifouling paints, may have caused the marked decline of B. japonica populations in Japan. PMID:16818241

  14. Welcoming Blue-Collar Scholars into the Ivory Tower: Developing Class-Conscious Strategies for Student Success. Series on Special Student Populations

    ERIC Educational Resources Information Center

    Soria, Krista M.

    2015-01-01

    "Welcoming Blue-Collar Scholars Into the Ivory Tower" is the first volume in a new book series designed to explore how institutional policies, practices, and cultures shape learning, development, and success for students who have been historically underserved or given limited consideration in the design of higher education contexts.

  15. Non-invasive quantitative micro-PIXE-RBS/EBS/EBS imaging reveals the lost polychromy and gilding of the Neo-Assyrian ivories from the Louvre collection.

    PubMed

    Albéric, Marie; Müller, Katharina; Pichon, Laurent; Lemasson, Quentin; Moignard, Brice; Pacheco, Claire; Fontan, Elisabeth; Reiche, Ina

    2015-05-01

    Antique objects are known to have been brightly colored. However, the appearance of these objects has changed over time and paint traces are rarely preserved. The surface of ivory objects (8th century B.C., Syria) from the Louvre museum collection (Paris) have been non-invasively studied by simultaneous particle-induced X-ray emission (PIXE) and Rutherford and elastic backscattering spectrometry (RBS/EBS) micro-imaging at the AGLAE facility (C2RMF, Paris). Qualitative 2D chemical images of elements ranging from Na to Pb on the surface of the ancient ivory carvings provide evidence of lost polychromy and gilding. Quantitative PIXE data of specific areas allow discrimination between traces of sediments and former polychromy. Different shades of blue can be differentiated from particular Pb/Cu ratios. The characterization of gilding based on RBS data demonstrates the exceptional technological skills of the Phoenician craftsmen supposed to have carved the Arslan Tash ivories. More precise reconstructions of the original polychromy compared to previous studies and a criterion for the authentication of ancient gilded ivory object are proposed. PMID:25770612

  16. Age assessment of ivory by analysis of 14C and 90Sr to determine whether there is an antique on hand.

    PubMed

    Schmied, Stefanie A K; Brunnermeier, Matthias J; Schupfner, Robert; Wolfbeis, Otto S

    2011-04-15

    A method is described to determine whether an elephant has died before 1955 or not. This is accomplished by determination of the radionuclides (14)C and (90)Sr in artifacts made of ivory. The reliability of this method is considerably increased by double nuclide analysis and therefore is applicable for judicial expert opinions. PMID:21371831

  17. The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education. Counterpoints: Studies in the Postmodern Theory of Education. Volume 401

    ERIC Educational Resources Information Center

    Breault, Donna Adair; Callejo Perez, David M.

    2012-01-01

    "The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education" critically analyzes the operational behaviors of prestigious and prestige-seeking universities, particularly within the context of budget shortfalls and increasing competition. The book challenges entrepreneurial activities within universities by exploring…

  18. Welcoming Blue-Collar Scholars into the Ivory Tower: Developing Class-Conscious Strategies for Student Success. Series on Special Student Populations

    ERIC Educational Resources Information Center

    Soria, Krista M.

    2015-01-01

    "Welcoming Blue-Collar Scholars Into the Ivory Tower" is the first volume in a new book series designed to explore how institutional policies, practices, and cultures shape learning, development, and success for students who have been historically underserved or given limited consideration in the design of higher education contexts.…

  19. The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education. Counterpoints: Studies in the Postmodern Theory of Education. Volume 401

    ERIC Educational Resources Information Center

    Breault, Donna Adair; Callejo Perez, David M.

    2012-01-01

    "The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education" critically analyzes the operational behaviors of prestigious and prestige-seeking universities, particularly within the context of budget shortfalls and increasing competition. The book challenges entrepreneurial activities within universities by exploring

  20. Lava Reaching the Coast

    USGS Multimedia Gallery

    View looking south toward active flows on the coastal flats near Kalapana Gardens subdivision. The new flows entered the area from right center, crossing the end of Hwy 130, and burning through forest adjacent to the coast. The burned remains of trees and brush cover the surface of the new flows at ...

  1. Northwest Coast Indian Art.

    ERIC Educational Resources Information Center

    Manning, Thomas; Knecht, Elizabeth

    The visual art forms of the Northwest Coast Indian Tribes of Alaska (Haida, Tlingit, and Tsimshian) share common distinctive design elements (formline, ovoid, U-form, and curvilinear shapes) which are referred to as the "Northern Style." Designs represent events or characters taken from the oral tradition of song and legend. Characteristics of…

  2. Coast Salish Canoe Journey

    USGS Multimedia Gallery

    Coast Salish Canoe Journey 2009 landing in Pillar Point, WA.  Each year Northwest Indian tribes collaborate with USGS to measure salinity, temperature, pH, and dissolved oxygen in the Salish Sea.  The Swinomish Tribe was recently awarded national recognition for their leadership in buildin...

  3. Alaskan Coast Seafloor

    USGS Multimedia Gallery

    This photograph shows USGS scientists collecting data off the Arctic Coastal Plain of northern Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreline habitats an...

  4. California Coast Seafloor

    USGS Multimedia Gallery

    This photograph is of the seafloor off the California coast and shows rock outcrop, encrusting sponge, cup corals, red sea star and a female kelp greenling. This photograph supports the California Seafloor Mapping Program (CSMP), which was initiated in 2007 by the California Ocean Protection Council...

  5. Northwest Coast Indian Art.

    ERIC Educational Resources Information Center

    Manning, Thomas; Knecht, Elizabeth

    The visual art forms of the Northwest Coast Indian Tribes of Alaska (Haida, Tlingit, and Tsimshian) share common distinctive design elements (formline, ovoid, U-form, and curvilinear shapes) which are referred to as the "Northern Style." Designs represent events or characters taken from the oral tradition of song and legend. Characteristics of

  6. Coast Guard Firefighting Module

    NASA Technical Reports Server (NTRS)

    1977-01-01

    NASA and the U.S. Coast Guard are jointly developing a lightweight, helicopter-transportable, completely self-contained firefighting module for combating shipboard and dockside fires. The project draws upon NASA technology in high-capacity rocket engine pumps, lightweight materials and compact packaging.

  7. California Coast Seafloor

    USGS Multimedia Gallery

    This photograph is of the seafloor off the California coast and shows jellyfish in a water column. This photograph supports the California Seafloor Mapping Program (CSMP), which was initiated in 2007 by the California Ocean Protection Council. Data collected during this project reveal the seafloor o...

  8. California Coast Seafloor

    USGS Multimedia Gallery

    This photograph is of the seafloor off the California coast and shows coarse sand, shells and a sunflower sea star. This photograph supports the California Seafloor Mapping Program (CSMP), which was initiated in 2007 by the California Ocean Protection Council. Data collected during this project reve...

  9. Multi-component diffusion between molten SiO2 inclusions and surrounding felsic melt in an indochinite: Tektites as natural laboratories

    NASA Astrophysics Data System (ADS)

    Macris, C. A.; Eiler, J. M.; Asimow, P. D.; Stolper, E. M.

    2013-12-01

    Tektites are natural glasses thought to have formed as a result of melting and quenching of distally ejected terrestrial material upon hypervelocity (>11 km/s) impact on Earth. Some tektites contain inclusions of lechatelierite (nearly pure SiO2 glass; 99-100 wt. % SiO2), generally thought to be the amorphous relicts of partially digested quartz grains (Koeberl, 1994). Electron and ion microprobe analyses of major and minor elements were performed on transects between lechatelierite inclusions and the surrounding felsic glass in an indochinite (sample from Newman et al., 1995). The surrounding glass is peraluminous with an average composition of 73.4 wt.% SiO2, 12.8 wt.% Al2O3, 4.5 wt. % FeO, 2.3 wt.% K2O, and < 2 wt.% (each) CaO, MgO, Na2O, and TiO2. The boundary between the lechatelierite and felsic glass is broad (~30 ?m), with complex concentration profiles reflecting diffusion between the two melts at high temperatures (>2200 C for formation of lechatelierite; Bunch et al., 2012) prior to quenching. Although all components except SiO2 are pinned to near zero at the same point at the lechatelierite end of the profiles, the shapes of the oxide concentration profiles differ, with Ca and Mg falling off from their far-field values first, followed in order by Fe, Ti, Al, Na, and K. K has apparently propagated the longest distance, diffusing faster than other components from the surrounding melt toward the lechatelierite. Furthermore, concentration profiles of K2O systematically increase, reach a maximum, then decrease closest to lechatelierite, indicating uphill diffusion of K against its concentration gradient. All concentration profiles are asymmetric, becoming steepest towards the most silicic portions of the interdiffusion zone approaching lechatelierite, likely due to the sharp compositional contrast between matrix glass and inclusions. Sato (1974) observed similar alkali enrichment in coronas around quartz xenocrysts in basalt and andesite, where K, and to a lesser degree Na, diffused against their concentration gradients. The uphill diffusion of alkalis in corona glass surrounding quartz was interpreted by Sato (1974) with a diffusion model assuming non-ideality of alkali elements in silicate melt, in which diffusion occurs according to the chemical potential gradient of each species. Preliminary calculations using the MELTS (Ghiorso and Sack, 1995) activity-composition model to transform the composition profiles across lechatelierite and felsic glass into chemical potential profiles (at 2200 C) indicate that all components, including K2O, diffuse down their own chemical potential gradients. We will investigate these phenomena further in attempt to model the observed profiles. A deeper understanding of this problem may inform the factors controlling diffusion coefficients in silicate melts derived from crustal material, as well as the thermal histories of tektites. Bunch T.E. et al. (2012) P NATL ACAD SCI 109:1903-1912 Ghiorso M.S., Sack R.O. (1995) CONTRIB MINERAL PETR 119:197-212 Koeberl C. (1994) GEOL S AM S 133-151 Newman S. et al. (1995) LPS XXVI 26:1039-1040 Sato H. (1974) CONTRIB MINERAL PETROL 50:49-64

  10. Northeast Coast, Hokkaido, Japan

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The northeast coast of Hokkaido and Kunashir Island, Japan (44.0N, 143.0E) are seen bordered by drifting sea ice. The sea ice has formed a complex pattern of eddies in response to surface water currents and winds. Photos of this kind aid researchers in describing local ocean current patterns and the effects of wind speed and direction on the drift of surface material, such as ice floes or oil. Kunashir is the southernmost of the Kuril Islands.

  11. Maine coast winds

    SciTech Connect

    Avery, Richard

    2000-01-28

    The Maine Coast Winds Project was proposed for four possible turbine locations. Significant progress has been made at the prime location, with a lease-power purchase contract for ten years for the installation of turbine equipment having been obtained. Most of the site planning and permitting have been completed. It is expect that the turbine will be installed in early May. The other three locations are less suitable for the project, and new locations are being considered.

  12. Poetry Expressed: Dance Diversity in the African Subcontinent--Perceptions, Misperceptions, and Preservation (with a Focus on the Ivory Coast and Mali)

    ERIC Educational Resources Information Center

    Doumbia, Kadidia

    2013-01-01

    In this article, the author explains how African dances are created in many social venues as a form of communicating within specific societies. However, from her travels, she has discovered that there are many misconceptions outside of the continent, and many people who view African dances as exotic or as only entertainment. The article discusses

  13. Characterization of weathering profile in granites and volcanosedimentary rocks in West Africa under humid tropical climate conditions. Case of the Dimbokro Catchment (Ivory Coast)

    NASA Astrophysics Data System (ADS)

    Koita, M.; Jourde, H.; Koffi, K. J. P.; da Silveira, K. S.; Biaou, A.

    2013-06-01

    In granitic rocks, various models of weathering profile have been proposed, but never for the hard rocks of West Africa. Besides, in the literature there is no description of the weathering profile in volcanosedimentrary rocks. Therefore, we propose three models describing the weathering profiles in granites, metasediments, and volcanic rocks for hard rock formations located in West Africa. For each of these models proposed for granitic and volcanosedimentary rocks of the Dimbokro catchment, vertical layered weathering profiles are described, according to the various weathering and erosion cycles (specific to West Africa) that the geological formations of the Dimbokro catchment experienced from the Eocene to the recent Quaternary period. The characterization of weathering profiles is based on: i) bedrocks and weathering profile observations at outcrop, and ii) interpretation and synthesis of geophysical data and lithologs from different boreholes. For each of the geological formations (granites, metasediments, and volcanic rocks), their related weathering profile model depicted from top to bottom comprises four separate layers: alloterite, isalterite, fissured layer, and fractured fresh basement. These weathering profiles are systematically covered by a soil layer. Though granites, metasediments and volcanic rocks of the Dimbokro catchment experience the same weathering and erosion cycles during the palaeoclimatic fluctuations from Eocene to recent Quaternary period, they exhibit differences in thickness. In granites, the weathering profile is relatively thin due to the absence of iron crust which protects weathering products against dismantling. In metasediments and volcanic rocks iron crusts develop better than in granites; in these rocks the alterite are more resistant to dismantling.

  14. The Economic Value of Breastfeeding (With Results from Research Conducted in Ghana and the Ivory Coast). Cornell International Nutrition Monograph Series Number 6.

    ERIC Educational Resources Information Center

    Greiner, Ted; And Others

    This monograph focuses attention on economic considerations related to infant feeding practices in developing countries. By enlarging on previous methodologies, this paper proposes to improve the accuracy of past estimates of the economic value of human milk, or more specifically, the practice of breastfeeding. The theoretical model employed…

  15. The Economic Value of Breastfeeding (With Results from Research Conducted in Ghana and the Ivory Coast). Cornell International Nutrition Monograph Series Number 6.

    ERIC Educational Resources Information Center

    Greiner, Ted; And Others

    This monograph focuses attention on economic considerations related to infant feeding practices in developing countries. By enlarging on previous methodologies, this paper proposes to improve the accuracy of past estimates of the economic value of human milk, or more specifically, the practice of breastfeeding. The theoretical model employed

  16. Can the Language of Rights Get Hold of the Complex Realities of Child Domestic Work?: The Case of Young Domestic Workers in Abidjan, Ivory Coast

    ERIC Educational Resources Information Center

    Jacquemin, Melanie

    2006-01-01

    This review examines refractions of children's rights in development practice from an anthropological point of view and considers the case of young domestic girls working in Abidjan. The author argues that child labour legislation and the children's rights perspective in Abidjan is permeated by patriarchal values that mask the exploitation of work

  17. Coasts in Crisis

    SciTech Connect

    Hinrichsen, D.

    1996-11-01

    Coastal areas are staggering under an onslaught of human activity. We are presently in the process of destroying 70 percent of the world`s 600,000 square kilometers of coral reefs, an ecosystem containing some 200,000 different species and rivaling tropical rain forests in biodiversity. A combination of pollution, habitat destruction, and gross overfishing has led to the collapse of major fisheries and paved the way for malnutrition and disease in regions where people fish for subsistence. Globally, little is being done to manage the crisis of our coasts. Management strategies, if they exist at all, often deal with economic development along a wafer-thin strip of coastal land. Resource degradation is ignored, and watershed management is mostly rhetoric. Although some 55 countries have drawn up coastal management plans, only a handful have been properly implemented. Coasts must be managed in an integrated manner that takes into account the full range of human activities. Initiating this process is costly, time-consuming, and difficult. Yet we have more than three decades of accumulated experience to draw on.

  18. 40Ar-39Ar step-heating of impact glasses from the Nrdlinger Ries impact craterImplications on excess argon in impact melts and tektites

    NASA Astrophysics Data System (ADS)

    Schwarz, Winfried H.; Lippolt, Hans J.

    2014-06-01

    Seven impact melts from various places in the Nrdlinger Ries were dated by 40Ar-39Ar step-heating. The aim of these measurements was to increase the age data base for Ries impact glasses directly from the Ries crater, because there is only one Ar-Ar step-heating spectrum available in the literature. Almost all samples display saddle-shaped age spectra, indicating the presence of excess argon in most Ries glass samples, most probably inherited argon from incompletely degassed melt and possibly also excess argon incorporated during cooling from adjacent phases. In contrast, moldavites usually contain no inherited argon, probably due to their different formation process implying solidification during ballistic transport. The plateau age of the only flat spectrum is 14.60 0.16 (0.20) Ma (2?), while the total age of this sample is 14.86 0.20 (0.22) Ma (isochron age: 14.72 0.18 [0.22] Ma [2?]), proofing the chronological relationship of the Ries impact and moldavites. The total ages of the other samples range between 15.77 0.52 and 20.4 1.0 Ma (2?), implying approximately 2-40% excess 40Ar (compared to the nominal age of the Ries crater) in respective samples. Thus, the age of 14.60 0.16 (0.20) (2?) (14.75 0.16 [0.20 Ma] [2?], calculated using the most recent suggestions for the K decay constants) can be considered as reliable and is within uncertainties indistinguishable from the most recent compilation for the age of the moldavite tektites.

  19. Eroding Shoreline Along Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows ice-wedge polygons and an eroding shoreline at Cape Halkett on the Beaufort Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shore...

  20. Polar Bear Along Alaska's Coast

    USGS Multimedia Gallery

    A polar bear stands on a low-lying barrier shoal near the Huluhula River on the Beaufort Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreline habi...

  1. Grizzly Bears Along Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows two grizzly bears frolic on the tundra near the Avak River on the Chukchi Sea coast of Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreli...

  2. Princess Astrid Coast, Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The continent of Antarctica is almost completely covered by a thick blanket of ice, punctuated only by steep mountain peaks and a handful of dry valleys. Antarctica is also ringed by a permanent ice shelf, and that is surrounded by seasonal sea ice. The image above, acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) on September 26, 2001, shows many of the types of ice found in Antarctica. At the bottom of the image is the ice of the continental glacier, which is up to 4,000 meters thick in the interior. These thick glaciers are held in place by coastal mountain ranges. Some ice does flow through the mountains, spilling onto the relatively flat land of the Princess Astrid Coast. Cold air also spills over the mountains, creating very strong and persistent 'katabatic' winds. These scour the snow off the tops of the glaciers, leaving pale blue patches of bare ice. Above the coastline is the ice shelf, which is much smoother. There, glacial ice actually floats on the sea surface. Beyond that is the chaotic surface of the sea ice, which has been solidifying all winter long. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  3. Andrew spares Florida Coast

    NASA Astrophysics Data System (ADS)

    Bush, Susan

    When geologists heard of the intensity of Hurricane Andrew, which struck the Florida coast on August 25 and then moved on to southern Louisiana, they were expecting the same kinds of coastal damage that Hurricane Hugo brought to the Caribbean and Carolina shores in 1989. Both storms were category 4 hurricanes, having winds of 131-155 mph and surges of 13-18 feet. However, the coastal damage never materialized, leaving geologists to analyze the factors that lessened the impact of the storm. For minimum coastal damage, you couldn't have designed a better storm, said Orrin Pilkey, director of the Program for the Study of Developed Shorelines (PSDS) in Durham, N.C. This was due in part to the nature of the storm itself and where it hit land, and in part to the regional geology, said Rob Thieler of PSDS. Despite the huge amounts of damage to buildings, there was virtually no evidence of coastal process destruction, he said.

  4. Upper Texas Gulf Coast, USA

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The upper Texas Gulf Coast (29.0N, 95.5W), though mostly cloud covered in this view, is still readily identifiable because of the distinctive features of the Texas Gulf Coast. Galveston Island, Galveston Bay and the coastal prairie are in the clear. Most of the city of Houston is cloud covered but the Gulf Freeeway connecting Houston and Galveston can be traced for most of it's route.

  5. Honduras: Caribbean Coast.

    PubMed

    Harborne, A R; Afzal, D C; Andrews, M J

    2001-12-01

    The coast of Honduras, Central America, represents the southern end of the Mesoamerican Barrier Reef System, although its marine resources are less extensive and studied than nearby Belize and Mexico. However, the coastal zone contains mainland reef formations, mangroves, wetlands, seagrass beds and extensive fringing reefs around its offshore islands, and has a key role in the economy of the country. Like most tropical areas, this complex of benthic habitats experiences limited annual variation in climatic and oceanographic conditions but seasonal and occasional conditions, particularly coral bleaching and hurricanes, are important influences. The effects of stochastic factors on the country's coral reefs were clearly demonstrated during 1998 when Honduras experienced a major hurricane and bleaching event. Any natural or anthropogenic impacts on reef health will inevitably affect other countries in Latin America, and vice versa, since the marine resources are linked via currents and the functioning of the system transcends political boundaries. Much further work on, for example, movement of larvae and transfer of pollutants is required to delineate the full extent of these links. Anthropogenic impacts, largely driven by the increasing population and proportion of people living in coastal areas, are numerous and include key factors such as agricultural run-off, over-fishing, urban and industrial pollution (particularly sewage) and infrastructure development. Many of these threats act synergistically and, for example, poor watershed management via shifting cultivation, increases sedimentation and pesticide run-off onto coral reefs, which increases stress to corals already affected by decreasing water quality and coral bleaching. Threats from agriculture and fishing are particularly significant because of the size of both industries. The desire to generate urgently required revenue within Honduras has also led to increased tourism which provides an overarching stress to marine resources since most tourists spend time in the coastal zone. Hence the last decade has seen a dramatic increase in coastal development, a greater requirement for sewage treatment and more demand for freshwater, particularly in the Bay Islands. Although coastal zone management is relatively recent in Honduras, it is gaining momentum from both large-scale initiatives, such as the Ministry of Tourism's 'Bay Islands Environmental Management Project', and national and international NGO projects. For example, a series of marine protected areas and legislative regulations have been established, but management capacity, enforcement and monitoring are limited by funding, expertise and training. Existing and future initiatives, supported by increased political will and environmental awareness of stakeholders, are vital for the long-term economic development of the country. PMID:11827108

  6. Resource Wars and Conflict Ivory: The Impact of Civil Conflict on Elephants in the Democratic Republic of Congo - The Case of the Okapi Reserve

    PubMed Central

    Beyers, Rene L.; Hart, John A.; Sinclair, Anthony R. E.; Grossmann, Falk; Klinkenberg, Brian; Dino, Simeon

    2011-01-01

    Human conflict generally has substantial negative impacts on wildlife and conservation. The recent civil war (1995-2006) in the Democratic Republic of Congo (DRC) resulted in a significant loss of wildlife, including elephants, due to institutional collapse, lawlessness and unbridled exploitation of natural resources such as minerals, wood, ivory and bushmeat. We used data from distance sampling surveys conducted before and after the war in a protected forest, the Okapi Faunal Reserve, to document changes in elephant abundance and distribution. We employed Generalized Additive Models to relate changes in elephant distribution to human and environmental factors. Populations declined by nearly fifty percent coinciding with a major increase in elephant poaching as indicated by reports of ivory trade during the war. Our results suggest that humans influenced elephant distribution far more than habitat, both before and after the war, but post-war models explained more of the variation. Elephant abundance declined more, closer to the park boundary and to areas of intense human activity. After the war, elephant densities were relatively higher in the centre of the park where they were better protected, suggesting that this area may have acted as a refuge. In other sites in Eastern DRC, where no protection was provided, elephants were even more decimated. Post-war dynamics, such as weakened institutions, human movements and availability of weapons, continue to affect elephants. Survival of remaining populations and recovery will be determined by these persistent factors and by new threats associated with growing human populations and exploitation of natural resources. Prioritizing wildlife protection, curbing illegal trade in ivory and bushmeat, and strengthening national institutions and organizations in charge of conservation will be crucial to counter these threats. PMID:22096529

  7. Resource wars and conflict ivory: the impact of civil conflict on elephants in the Democratic Republic of Congo--the case of the Okapi Reserve.

    PubMed

    Beyers, Rene L; Hart, John A; Sinclair, Anthony R E; Grossmann, Falk; Klinkenberg, Brian; Dino, Simeon

    2011-01-01

    Human conflict generally has substantial negative impacts on wildlife and conservation. The recent civil war (1995-2006) in the Democratic Republic of Congo (DRC) resulted in a significant loss of wildlife, including elephants, due to institutional collapse, lawlessness and unbridled exploitation of natural resources such as minerals, wood, ivory and bushmeat. We used data from distance sampling surveys conducted before and after the war in a protected forest, the Okapi Faunal Reserve, to document changes in elephant abundance and distribution. We employed Generalized Additive Models to relate changes in elephant distribution to human and environmental factors. Populations declined by nearly fifty percent coinciding with a major increase in elephant poaching as indicated by reports of ivory trade during the war. Our results suggest that humans influenced elephant distribution far more than habitat, both before and after the war, but post-war models explained more of the variation. Elephant abundance declined more, closer to the park boundary and to areas of intense human activity. After the war, elephant densities were relatively higher in the centre of the park where they were better protected, suggesting that this area may have acted as a refuge. In other sites in Eastern DRC, where no protection was provided, elephants were even more decimated. Post-war dynamics, such as weakened institutions, human movements and availability of weapons, continue to affect elephants. Survival of remaining populations and recovery will be determined by these persistent factors and by new threats associated with growing human populations and exploitation of natural resources. Prioritizing wildlife protection, curbing illegal trade in ivory and bushmeat, and strengthening national institutions and organizations in charge of conservation will be crucial to counter these threats. PMID:22096529

  8. Using Lidar-derived 3-D Vegetation Structure Maps to Assist in the Search for the Ivory- billed Woodpecker

    NASA Astrophysics Data System (ADS)

    Hofton, M. A.; Blair, J. B.; Rabine, D.; Dubayah, R.; Greim, H.

    2006-12-01

    Averaging about 20 inches in length, the ivory-billed woodpecker is among the world's largest woodpeckers. It once ranged through swampy forests in the southeastern and lower Mississippi valley states, and until recently was believed to have become extinct in the 1940's when commercial logging destroyed its last known habitat. Recent sightings however, may indicate the birds' survival in remaining bottomland hardwood forest adjacent to the Cache and White Rivers in Arkansas. In June-July 2006, NASA's Laser Vegetation Imaging Sensor (LVIS) was used to map approximately 5000 km2 of the White River National Wildlife Refuge in Arkansas, including sites where recent possible sightings of the bird occurred. LVIS is an airborne, medium- footprint (5- to 25-meter diameter), full waveform-recording, airborne, scanning lidar system which has been used extensively for mapping forest structure, habitat, carbon and natural hazards. The system digitally records the shape of the returning laser echo, or waveform, after its interaction with the various reflecting surfaces of the earth (leaves, branches, ground, etc.), providing a true 3-dimensional record of the surface structure. Data collected included ground elevation and canopy height measurements for each laser footprint, as well as the vertical distribution of intercepted surfaces (the return waveform). Experimental metrics such as canopy structure metrics based on energy quartiles, as well as ground energy/canopy cover and waveform complexity metrics will be derived from each waveform. The project is a collaborative effort between the University of Maryland, NASA, USGS, and the US Fish and Wildlife Service. The LVIS-generated data of the 3- D vegetation structure and underlying terrain will be used as a means to guide local, ground-based search efforts in the upcoming field season as well as identify the remaining areas of habitat suitable for protection should the bird be found.

  9. Real-time PCR detection and quantification of elephantid DNA: species identification for highly processed samples associated with the ivory trade.

    PubMed

    Wozney, Kristyne Michelle; Wilson, Paul J

    2012-06-10

    The ivory industry is the single most serious threat to global elephant populations. A highly sensitive, species-specific real-time PCR assay has been developed to detect and quantify African elephant (Loxodonta africana), Asian elephant (Elephas maximus) and Woolly Mammoth (Mammuthus primigenius) mitochondrial DNA from highly processed samples involved in the international ivory trade. This assay is especially useful for highly processed samples where there are no distinguishing morphological features to identify the species of origin. Using species-specific Taqman() probes targeting a region of the mitochondrial cytochrome b gene, we developed an assay that can be used to positively identify samples containing elephant or Woolly mammoth DNA faster and more cost-effectively than traditional sequencing methods. Furthermore, this assay provides a diagnostic result based on probe hybridization that eliminates ambiguities associated with traditional DNA sequence protocols involving low template DNA. The real-time method is highly sensitive, producing accurate and reproducible results in samples with as few as 100 copies of template DNA. This protocol can be applied to the enforcement of the Convention on the International Trade of Endangered Species (CITES), when positive identification of species from illegally traded products is required by conservation officers in wildlife forensic cases. PMID:22257967

  10. Bryan Coast, English Coast, Alexander Island, Fallieres Coast, and Bellingshausen Sea, Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image of Antarctica shows the Bryan Coast (lower left), the English Coast (lower central), Alexander Island (middle right), the Fallieres Coast (top right), and the Bellingshausen Sea. The entire continent has been dedicated to peaceful scientific investigation since 1961, with the signing of the Antarctic Treaty.The waters surrounding Antarctica are intensely cold. Salt water freezes at -2C, allowing sea ice to form. The middle left portion of the image shows quite a lot of sea ice in the Bellingshausen Sea. During the Antarctic winter, when data for this image was acquired, Antarctica doubles in size to about 28.5 million square km (or about 11 million square miles), and temperatures in the -60C range are common.This true-color image was compiled from MODIS data gathered March 29, 2002. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  11. Caribou Tracks Along Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows caribou tracks on ice-wedge polygons near Garry Creek in Alaska. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense and energy purposes, natural shoreline habitats and nearby Native ...

  12. Chalk coast dynamics: Implications for understanding rock coast evolution

    NASA Astrophysics Data System (ADS)

    Moses, Cherith; Robinson, David

    2011-12-01

    Rock cliffs and shore platforms are linked components of the world's coastal zone. Understanding of the dynamics of their relationships has been hindered by the often imperceptible changes that occur within human time scales. The Cretaceous Chalk coasts of northwest Europe, and particularly those of southeast England, are among the most dynamic, and most intensively studied, cliffed rock coasts in the world. Perceptible changes to both cliffs and platforms have been measured on monthly, seasonal, annual and decadal time scales. Through a review of previously published data and the addition of data not previously published, average cliff retreat rates are calculated as 0.49 0.38 m y - 1 and platform erosion rates 3.999 3.208 mm y - 1 . This paper highlights some of the interactions over time and space between process and measurement that continue to limit our understanding of the dynamics of rock coasts; in particular the link between rates of cliff retreat and platform erosion. It concludes by identifying fruitful areas for future research.

  13. California coast nearshore processes study

    NASA Technical Reports Server (NTRS)

    Pirie, D. M.; Steller, D. D. (principal investigators)

    1973-01-01

    The author has identified the following significant results. During the period 1 May to 30 June 1973 material was processed and interpreted for use in analyzing the three ocean seasons along the California coast. ERTS imagery from the first season of the year, called the Davidson Current period, was mosaiced and analyzed. The second season of the year, the Upwelling period, was mosaiced and interpretation was initiated. Imagery for the third ocean season, the Oceanic period, is being collected for future study.

  14. Red Tide off Texas Coast

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Red tides (algae) bloomed late this summer along a 300-mile stretch of Texas' Gulf Coast, killing millions of fish and shellfish as well as making some people sick. State officials are calling this the worst red tide bloom in 14 years. The algae produces a poison that paralyzes fish and prevents them from breathing. There is concern that the deadly algae could impact or even wipe out this year's oyster harvest in Texas, which usually peaks during the Thanksgiving and Christmas holidays. The red tides were first observed off the Texas coast in mid-August and have been growing steadily in size ever since. Red tides tend to bloom and subside rapidly, depending upon changes in wind speed and direction, water temperature, salinity, and rainfall patterns (as the algae doesn't do as well in fresher water). This true-color image of the Texas Gulf Coast was acquired on September 29, 2000, by the Moderate-resolution Imaging Spectroradiometer (MODIS) flying aboard NASA's Terra spacecraft. The red tide can be seen as the dark reddish discoloration in the ocean running southwest to northeast along the coast. In this scene, the bloom appears to be concentrated north and east of Corpus Christi, just off Matagorda Island. The image was made at 500-meter resolution using a combination of MODIS' visible bands 1 (red), 4 (green), and 3 (blue). The city of Houston can be seen clearly as the large, greyish cluster of pixels to the north and west of Galveston Bay, which is about mid-way up the coastline in this image. Also visible in this image are plumes of smoke, perhaps wildfires, both to the north and northeast of Houston. For more information about red tides, refer to the Texas Red Tide Web site. Image courtesy Andrey Savtchenko, MODIS Data Support Team, and the MODIS Ocean Team, NASA's Goddard Space Flight Center

  15. Meteoritic material at five large impact craters

    NASA Technical Reports Server (NTRS)

    Palme, H.; Janssens, M.-J.; Takahashi, H.; Anders, E.; Hertogen, J.

    1978-01-01

    The paper analyzes the meteoritic material at five multikilometer craters: Clearwater (Lac a l'Eau Claire) East and West (22 and 32 km), Manicouagan (70 km) and Mistastin (28 km), all in Canada; and Lake Bosumtwi (10.5 km), Ghana, which is associated with Ivory Coast tektites. Radiochemical neutron activation analysis is applied to 16 crater samples for the siderophile trace elements Ir, Os, Pd, Ni, Ge, and Re, which are depleted to varying degrees in the earth's crust but are abundant in all meteorites except achondrites. It is found that only two samples, both from Clearwater, exhibit a strong meteoritic signal. The remaining ones fall within or slightly above the range for terrestrial rocks, and therefore at best contain only small meteoritic components. Clearwater East is the first terrestrial impact crater to be associated with a stony meteorite (a C1 or C2 chondrite).

  16. Time-resolved microscopy reveals the driving mechanism of particle formation during ultrashort pulse laser ablation of dentin-like ivory

    NASA Astrophysics Data System (ADS)

    Domke, Matthias; Gavrilova, Anna; Rapp, Stephan; Frentzen, Matthias; Meister, Joerg; Huber, Heinz P.

    2015-07-01

    In dental health care, the application of ultrashort laser pulses enables dental tissue ablation free from thermal side effects, such as melting and cracking. However, these laser types create undesired micro- and nanoparticles, which might cause a health risk for the patient or surgeon. The aim of this study was to investigate the driving mechanisms of micro- and nanoparticle formation during ultrashort pulse laser ablation of dental tissue. Time-resolved microscopy was chosen to observe the ablation dynamics of mammoth ivory after irradiation with 660 fs laser pulses. The results suggest that nanoparticles might arise in the excited region. The thermal expansion of the excited material induces high pressure in the surrounding bulk tissue, generating a pressure wave. The rarefaction wave behind this pressure wave causes spallation, leading to ejection of microparticles.

  17. Time-resolved microscopy reveals the driving mechanism of particle formation during ultrashort pulse laser ablation of dentin-like ivory.

    PubMed

    Domke, Matthias; Gavrilova, Anna; Rapp, Stephan; Frentzen, Matthias; Meister, Joerg; Huber, Heinz P

    2015-07-01

    In dental health care, the application of ultrashort laser pulses enables dental tissue ablation free from thermal side effects, such as melting and cracking. However, these laser types create undesired micro- and nanoparticles, which might cause a health risk for the patient or surgeon. The aim of this study was to investigate the driving mechanisms of micro- and nanoparticle formation during ultrashort pulse laser ablation of dental tissue. Time-resolved microscopy was chosen to observe the ablation dynamics of mammoth ivory after irradiation with 660 fs laser pulses. The results suggest that nanoparticles might arise in the excited region. The thermal expansion of the excited material induces high pressure in the surrounding bulk tissue, generating a pressure wave. The rarefaction wave behind this pressure wave causes spallation, leading to ejection of microparticles. PMID:26172613

  18. Traditional West Coast Native Medicine

    PubMed Central

    Deagle, George

    1988-01-01

    An important part of the complex culture of the Native people of Canada's Pacific coast is the traditional system of medicine each culture has developed. Population loss from epidemics and the influence of dominant European cultures has resulted in loss of many aspects of traditional medicine. Although some Native practices are potentially hazardous, continuation of traditional approaches to illness remains an important part of health care for many Native people. The use of devil's club plant by the Haida people illustrates that Native medicine has both spiritual and physical properties. Modern family practice shares many important foundations with traditional healing systems. PMID:21253031

  19. 47 CFR 80.1119 - Receipt and acknowledgement of distress alerts by coast stations and coast earth stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... by coast stations and coast earth stations. 80.1119 Section 80.1119 Telecommunication FEDERAL... § 80.1119 Receipt and acknowledgement of distress alerts by coast stations and coast earth stations. (a... for coast stations.) (b) Coast earth stations in receipt of distress alerts must ensure that they...

  20. 47 CFR 80.1119 - Receipt and acknowledgement of distress alerts by coast stations and coast earth stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... by coast stations and coast earth stations. 80.1119 Section 80.1119 Telecommunication FEDERAL... § 80.1119 Receipt and acknowledgement of distress alerts by coast stations and coast earth stations. (a... for coast stations.) (b) Coast earth stations in receipt of distress alerts must ensure that they...

  1. 47 CFR 80.1119 - Receipt and acknowledgement of distress alerts by coast stations and coast earth stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... by coast stations and coast earth stations. 80.1119 Section 80.1119 Telecommunication FEDERAL... § 80.1119 Receipt and acknowledgement of distress alerts by coast stations and coast earth stations. (a... for coast stations.) (b) Coast earth stations in receipt of distress alerts must ensure that they...

  2. 47 CFR 80.1119 - Receipt and acknowledgement of distress alerts by coast stations and coast earth stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... by coast stations and coast earth stations. 80.1119 Section 80.1119 Telecommunication FEDERAL... § 80.1119 Receipt and acknowledgement of distress alerts by coast stations and coast earth stations. (a... for coast stations.) (b) Coast earth stations in receipt of distress alerts must ensure that they...

  3. 47 CFR 80.1119 - Receipt and acknowledgement of distress alerts by coast stations and coast earth stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... by coast stations and coast earth stations. 80.1119 Section 80.1119 Telecommunication FEDERAL... § 80.1119 Receipt and acknowledgement of distress alerts by coast stations and coast earth stations. (a... for coast stations.) (b) Coast earth stations in receipt of distress alerts must ensure that they...

  4. Ebony and Ivory

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image from the Mars Exploration Rover Opportunity's front hazard-avoidance camera focuses on a target called 'Goal 5.' Goal 5, examined during the 'Eagle Crater' soil survey, is a wind-rippled spot on the upper part of the crater , which the miniature thermal emission spectrometer shows is higher in hematite content compared to other soils within the crater. The light soil in the center of the image is referred to as 'Lanikai' -- an inspiration from the white sand beaches of Hawaii. The dark soil is referred to as 'Punaluu' after the black sand Hawaiian beaches.

  5. No Ivory Tower.

    ERIC Educational Resources Information Center

    Doti, James L.

    2002-01-01

    Measured the impact of economic cycles on independent colleges and universities, using a national tuition discounting survey. Found that economic cycles and pricing pressures have measurable and predictable effects on independent higher education. (EV)

  6. Scaling the Ivory Tower

    ERIC Educational Resources Information Center

    Watson, Jamal Eric

    2011-01-01

    It used to be that newly minted Ph.D.s had to establish themselves and cut their academic teeth at less competitive colleges and universities. That was certainly true for young Black scholars. The prospects of landing a coveted teaching position at one of the nation's eight Ivy League institutions were dim. In the years leading up to the Civil…

  7. Scaling the Ivory Tower

    ERIC Educational Resources Information Center

    Watson, Jamal Eric

    2011-01-01

    It used to be that newly minted Ph.D.s had to establish themselves and cut their academic teeth at less competitive colleges and universities. That was certainly true for young Black scholars. The prospects of landing a coveted teaching position at one of the nation's eight Ivy League institutions were dim. In the years leading up to the Civil

  8. Leaving the Ivory Tower

    ERIC Educational Resources Information Center

    DeCarlo, Carmine

    2010-01-01

    It all began with casual conversation between a university supervisor and classroom teachers and approval to use an unused classroom at a local elementary school. The space became the hub of an exciting professional development (PD) opportunity for classroom teachers. This article describes how hosting an on-site university science methods course

  9. Phytoplankton bloom along the coast of Namibia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This MODIS true-color image, acquired March 4, 2002, shows a phytoplankton bloom along the coast of Namibia. Phytoplankton is a microscopic organism that utilizes chlorophyll, which sunlight reflects off of to create this intense blue-green color in the water. Also prominent in this image is the Skeleton Coast Game Park, which runs along Namibia's northern coast and here glows a beautiful coral-orange color.

  10. West Coast Tsunami: Cascadia's Fault?

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Bernard, E. N.; Titov, V.

    2013-12-01

    The tragedies of 2004 Sumatra and 2011 Japan tsunamis exposed the limits of our knowledge in preparing for devastating tsunamis. The 1,100-km coastline of the Pacific coast of North America has tectonic and geological settings similar to Sumatra and Japan. The geological records unambiguously show that the Cascadia fault had caused devastating tsunamis in the past and this geological process will cause tsunamis in the future. Hypotheses of the rupture process of Cascadia fault include a long rupture (M9.1) along the entire fault line, short ruptures (M8.8 - M9.1) nucleating only a segment of the coastline, or a series of lesser events of M8+. Recent studies also indicate an increasing probability of small rupture occurring at the south end of the Cascadia fault. Some of these hypotheses were implemented in the development of tsunami evacuation maps in Washington and Oregon. However, the developed maps do not reflect the tsunami impact caused by the most recent updates regarding the Cascadia fault rupture process. The most recent study by Wang et al. (2013) suggests a rupture pattern of high- slip patches separated by low-slip areas constrained by estimates of coseismic subsidence based on microfossil analyses. Since this study infers that a Tokohu-type of earthquake could strike in the Cascadia subduction zone, how would such an tsunami affect the tsunami hazard assessment and planning along the Pacific Coast of North America? The rapid development of computing technology allowed us to look into the tsunami impact caused by above hypotheses using high-resolution models with large coverage of Pacific Northwest. With the slab model of MaCrory et al. (2012) (as part of the USGS slab 1.0 model) for the Cascadia earthquake, we tested the above hypotheses to assess the tsunami hazards along the entire U.S. West Coast. The modeled results indicate these hypothetical scenarios may cause runup heights very similar to those observed along Japan's coastline during the 2011 Japan tsunami,. Comparing to a long rupture, the Tohoku-type rupture may cause more serious impact at the adjacent coastline, independent of where it would occur in the Cascadia subduction zone. These findings imply that the Cascadia tsunami hazard may be greater than originally thought.

  11. Greenland's Coast in Holiday Colors

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Vibrant reds, emerald greens, brilliant whites, and pastel blues adorn this view of the area surrounding the Jakobshavn Glacier on the western coast of Greenland. The image is a false-color (near-infrared, green, blue) view acquired by the Multi-angle Imaging SpectroRadiometer's nadir camera. The brightness of vegetation in the near-infrared contributes to the reddish hues; glacial silt gives rise to the green color of the water; and blue-colored melt ponds are visible in the bright white ice. A scattering of small icebergs in Disco Bay adds a touch of glittery sparkle to the scene.

    The large island in the upper left is called Qeqertarsuaq. To the east of this island, and just above image center, is the outlet of the fast-flowing Jakobshavn (or Ilulissat) glacier. Jakobshavn is considered to have the highest iceberg production of all Greenland glaciers and is a major drainage outlet for a large portion of the western side of the ice sheet. Icebergs released from the glacier drift slowly with the ocean currents and pose hazards for shipping along the coast.

    The Multi-angle Imaging SpectroRadiometer views the daylit Earth continuously and the entire globe between 82 degrees north and 82 degrees south latitude is observed every 9 days. These data products were generated from a portion of the imagery acquired on June 18, 2003 during Terra orbit 18615. The image cover an area of about 254 kilometers x 210 kilometers, and use data from blocks 34 to 35 within World Reference System-2 path 10.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  12. 77 FR 56749 - Gulf Coast Ecosystem Restoration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ... HOUSE, Washington, September 10, 2012. [FR Doc. 2012-22807 Filed 9-12-12; 11:15 am] Billing code 3295-F2... Documents#0;#0; ] Executive Order 13626 of September 10, 2012 Gulf Coast Ecosystem Restoration By the..., Executive Order 13554 established a Gulf Coast Ecosystem Restoration Task Force (Task Force) to...

  13. 27 CFR 9.30 - North Coast.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false North Coast. 9.30 Section 9.30 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas 9.30 North Coast. (a) Name. The name of the viticultural...

  14. 27 CFR 9.104 - South Coast.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false South Coast. 9.104 Section 9.104 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas 9.104 South Coast. (a) Name. The name of the...

  15. Discovering the "-Ologies" on the Jurassic Coast

    ERIC Educational Resources Information Center

    Peacock, Alan

    2007-01-01

    The Jurassic Coast is Britain's only natural World Heritage site, a tangible time-line that takes one through 185 million years of history in 95 miles of coast. It provides individuals with a world-famous educational resource and an unrivalled outdoor classroom that has played a key role in the study of earth sciences. The author is keen to ignite

  16. Birds Take Flight on Alaska's Coast

    USGS Multimedia Gallery

    This photograph shows birds taking flight near Icy Cape on the Chukchi Sea coast of Alaska, an area that provides habitat for a variety of avian species. Coastal erosion along the Arctic coast is chronic, widespread and potentially accelerating, posing threats to infrastructure important for defense...

  17. Discovering the "-Ologies" on the Jurassic Coast

    ERIC Educational Resources Information Center

    Peacock, Alan

    2007-01-01

    The Jurassic Coast is Britain's only natural World Heritage site, a tangible time-line that takes one through 185 million years of history in 95 miles of coast. It provides individuals with a world-famous educational resource and an unrivalled outdoor classroom that has played a key role in the study of earth sciences. The author is keen to ignite…

  18. Systems Engineering of Coast Guard Aviator Training.

    ERIC Educational Resources Information Center

    Hall, Eugene R.; Caro, Paul W.

    This paper describes a total-program application of the systems engineering concept of the U.S. Coast Guard aviation training programs. The systems approach used treats all aspects of the training to produce the most cost-effective integration of academic, synthetic, and flight training for the production of graduate Coast Guard aviators. The…

  19. 33 CFR 23.15 - Coast Guard ensign.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard ensign. 23.15 Section 23.15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.15 Coast Guard ensign. The Coast Guard...

  20. 33 CFR 23.15 - Coast Guard ensign.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Coast Guard ensign. 23.15 Section 23.15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.15 Coast Guard ensign. The Coast Guard...

  1. 33 CFR 23.15 - Coast Guard ensign.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Coast Guard ensign. 23.15 Section 23.15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.15 Coast Guard ensign. The Coast Guard...

  2. 33 CFR 23.15 - Coast Guard ensign.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Coast Guard ensign. 23.15 Section 23.15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.15 Coast Guard ensign. The Coast Guard...

  3. 76 FR 7123 - Eleventh Coast Guard District Annual Marine Events

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-09

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Eleventh Coast Guard District Annual Marine Events AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY: The Coast Guard proposes to update and consolidate the list of marine events occurring annually within the Eleventh Coast...

  4. 76 FR 53329 - Eleventh Coast Guard District Annual Marine Events

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-26

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Eleventh Coast Guard District Annual Marine Events AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: The Coast Guard is updating and consolidating the list of marine events occurring annually within the Eleventh Coast Guard District. These...

  5. 76 FR 30575 - Eleventh Coast Guard District Annual Marine Events

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-26

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Eleventh Coast Guard District Annual Marine Events AGENCY: Coast Guard, DHS. ACTION: Supplemental notice of proposed rulemaking. SUMMARY: The Coast Guard... regulated area. DATES: Comments and related material must be received by the Coast Guard on or before...

  6. 33 CFR 23.15 - Coast Guard ensign.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Coast Guard ensign. 23.15 Section 23.15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.15 Coast Guard ensign. The Coast Guard...

  7. Ctenophores from the Oaxaca coast, including a checklist of species from the Pacific coast of Mexico.

    PubMed

    Ruiz-Escobar, Fernando; Valadez-Vargas, Diana K; Oliveira, Otto M P

    2015-01-01

    Ctenophores are poorly known in the tropical eastern Pacific, including the southern coast of Mexico. Previous records of ctenophores along the Pacific coast have been provided mainly from northern waters. For the coast of Oaxaca state, their occurrence has only been mentioned before at phylum level. In this paper, we provide the first three records of ctenophores for the Oaxacan coast, which represent new records of Beroe forskalii and Bolinopsis vitrea as well as the first record of Ocyropsis maculata in the tropical eastern Pacific. Descriptions of these three species, as well as a checklist of the ctenophores from the west coast of Mexico are provided. PMID:25947447

  8. Southwest coast of Greenland and Davis Strait

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image was taken by MODIS as it passed over the southwest coast of Greenland (right) and the Davis Strait (center and left). The Davis Strait connects Baffin Bay to the north and the Labrador Sea to the south, and separates Greenland from Baffin Island, Canada. The Davis Strait is part of the Northwest Passage, a navigable seaway connecting the Atlantic Ocean and the Pacific Ocean. The image shows the prevailing currents in the area, with the warm water of a branch of the North Atlantic Drift flowing northward along the Greenland coast, and the cold, iceberg-filled Labrador Current flowing southward along the Baffin Island coast.

  9. The Coast Guard Comes to Class.

    ERIC Educational Resources Information Center

    Fawcett, Paul

    2002-01-01

    Focuses on Sea Partners, by the United States Coast Guard, that enables students to understand how pollution affects the marine environment. Correlates the activities with the National Science Education Standards. (DDR)

  10. Eighteenth annual West Coast theoretical chemistry conference

    SciTech Connect

    1997-05-01

    Abstracts are presented from the eighteenth annual west coast theoretical chemistry conference. Topics include molecular simulations; quasiclassical simulations of reactions; photodissociation reactions; molecular dynamics;interface studies; electronic structure; and semiclassical methods of reactive systems.

  11. Hurricane Linda Off the Baja Coast

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Quick Time movie captures Hurricane Linda moving off the Baja California coast in September 1997. The strongest hurricane on record for the eastern Pacific at that time, Hurricane Linda invaded Southern California with winds that had gusted to 105 mph (174 kph). While off the coast of Mexico, her winds gusted up to 220 mph (354 kph). Earth science and weather studies are an important ongoing function of NASA and its affiliates.

  12. Fluctuations of cambial activity in relation to precipitation result in annual rings and intra-annual growth zones of xylem and phloem in teak (Tectona grandis) in Ivory Coast

    PubMed Central

    Di, Agathe; Kitin, Peter; Kouam, Franois N'Guessan; Van den Bulcke, Jan; Van Acker, Joris; Beeckman, Hans

    2012-01-01

    Background and Aims Teak forms xylem rings that potentially carry records of carbon sequestration and climate in the tropics. These records are only useful when the structural variations of tree rings and their periodicity of formation are known. Methods The seasonality of ring formation in mature teak trees was examined via correlative analysis of cambial activity, xylem and phloem formation, and climate throughout 15 years. Xylem and phloem differentiation were visualized by light microscopy and scanning electron microscopy. Key Results A 3 month dry season resulted in semi-deciduousness, cambial dormancy and formation of annual xylem growth rings (AXGRs). Intra-annual xylem and phloem growth was characterized by variable intensity. Morphometric features of cambium such as cambium thickness and differentiating xylem layers were positively correlated. Cambium thickness was strongly correlated with monthly rainfall (R2 = 07535). In all sampled trees, xylem growth zones (XGZs) were formed within the AXGRs during the seasonal development of new foliage. When trees achieved full leaf, the xylem in the new XGZs appeared completely differentiated and functional for water transport. Two phloem growth rings were formed in one growing season. Conclusions The seasonal formation pattern and microstructure of teak xylem suggest that AXGRs and XGZs can be used as proxies for analyses of the tree history and climate at annual and intra-annual resolution. PMID:22805529

  13. [In vitro activity of different fungicides on the growth in Mycosphaerella fijiensis var. difformis Stover and Dickson, Cladosporium musae Morelet and Deightoniella torulosa (Syd.) Ellis, isolated parasites of the banana phyllosphere in the Ivory Coast].

    PubMed

    Kon, Daouda; Badou, Odjochoumou Jean; Bomisso, Edson Lezin; Camara, Brahima; Ake, Sverin

    2009-05-01

    In Cte-d'Ivoire, banana leaf surfaces are attacked by Mycosphaerella fijiensis var. difformis, Cladosporium musae, and Deigthonielle torulosa. Control is based on fungicides recommanded for Mycosphaerella fijiensis. Fungicides belonging to triazoles and strobilurines types were added, at different concentrations, to the PDA medium, using this PDA medium containing no fungicide as the control. Mycelium disc and spores of Cladosporium musae, Mycosphaerella fijiensis and Deightoniella torulosa were put on the different media. Total inhibition of mycelium growth of every fungus on the PDA amended with propiconazole was observed. The fungicides used show different activities according to their concentration and their mode of action. The application of a fungicide should talke into account the pathogenic fungus involved in the leaf attacked. Against Mycosphaerella fijiensis var. difformis, the Ci(50) are different according to the concentrations (0.44 to 1.06 ppm). Correlations ranked from 0.71 to 0.91 are also different according to fungicide used. The Ci(50) of Cladosporium musae (0.10 to 2.44 ppm) and Deightoniella torulosa (0.26 to 0.52 ppm) are different and their correlations are respectively 0.78 to 0.99 and 0.86 to 0.95. An assessment of the sensitivity of parasitic fungi of banana can be made by mycelium growth measurement of fungi isolated from resistance zones. PMID:19393976

  14. The Reception and Animation of Out-of-School Educational Television Programs in the Ivory Coast: A Case Study of Four Villages. An English Summary by L. Theresa Silverman.

    ERIC Educational Resources Information Center

    Benveniste, Annie

    This impact study for a series of Out of School Television (OSTV--Tele Pour Tous) broadcasts on village water supplies presents a qualitative examination of some of the problems encountered in the organization of viewing groups in four selected villages. The research techniques used included questionnaires and feedback sheets on demographics, the

  15. Serum lactate levels in infants exposed peripartum to antiretroviral agents to prevent mother-to-child transmission of HIV: Agence Nationale de Recherches Sur le SIDA et les Hpatites Virales 1209 study, Abidjan, Ivory Coast

    PubMed Central

    Ekouevi, Didier Koumavi; Tour, Ramata; Becquet, Renaud; Viho, Ida; Sakarovitch, Charlotte; Rouet, Franois; Towne-Gold, Besigin; Fassinou, Patricia; Leroy, Valriane; Blanche, Stphane; Dabis, Franois

    2006-01-01

    Background Mitochondrial toxicity was described in infants exposed to long-term antiretroviral regimens (ARVs) containing nucleoside analogues for the prevention of mother-to-child transmission of HIV (PMTCT). We measured the serum lactate levels in children born to HIV-1 infected (HIV+) African women receiving short-term ARV PMTCT regimens. Methods A prospective study was conducted in women-child pairs from the third trimester of pregnancy to three months of life. The exposed group was formed by children exposed in utero to nucleoside analogue ARVs, zidovudine (ZDV) or ZDV + lamivudine (3TC) from 3236 weeks of amenorrhea until delivery. All these women received nevirapine single-dose (NVPsd) at the beginning of labor. The children received ZDV during the first 7 days of life and a NVPsd at day 3. The control group was formed by infants born to HIV+ women who had received NVPsd only and not exposed to nucleoside analogue ARVs. Serum lactate levels were measured at 4, 6 and 12 weeks of life by Cobas Integra 400. Results A total of 836 blood samples from 338 infants were collected (262 exposed and 76 controls). Median lactacidemia was 1.8 mmol/l, Interquartile Range [1.22.7 mmol/l]). Overall serum lactate levels ?2.5 mmol/l, defining hyperlactatemia were observed in 39 of the 292 infants who had at least two serum lactate measurements, 13.4%, 95% confidence Interval [9.617.8%]. The three-month period prevalence of hyperlactatemia did not differ between the exposed group (13.1%) and the control group (14.3%) (p=0.84). All serum lactate levels returned to normal values in all subsequent samples No case of symptomatic hyperlactatemia was detected during the study period. Conclusion Increased lactate levels were identified equally in infants whose mother received a short-term of nucleoside analogues or NVPsd for PMTCT. Although not rare, hyperlactatemia was not related to short-term exposure to nucleoside analogue ARVs PMID:16950945

  16. 33 CFR 23.12 - Coast Guard identifying insignia.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Coast Guard identifying insignia. 23.12 Section 23.12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.12 Coast Guard identifying...

  17. 33 CFR 23.20 - Coast Guard commission pennant.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Coast Guard commission pennant. 23.20 Section 23.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.20 Coast Guard commission...

  18. 33 CFR 52.42 - Views of the Coast Guard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Views of the Coast Guard. 52.42 Section 52.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Submissions by the Coast Guard and Other...

  19. 46 CFR 4.03-20 - Coast Guard district.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Coast Guard district. 4.03-20 Section 4.03-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Definitions § 4.03-20 Coast Guard district. A Coast Guard district is one of the...

  20. 46 CFR 90.10-9 - Coast Guard District Commander.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Coast Guard District Commander. 90.10-9 Section 90.10-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 90.10-9 Coast Guard District Commander. This term means an officer of the Coast...

  1. 49 CFR 850.30 - Procedures for Coast Guard investigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Procedures for Coast Guard investigation. 850.30... TRANSPORTATION SAFETY BOARD COAST GUARD-NATIONAL TRANSPORTATION SAFETY BOARD MARINE CASUALTY INVESTIGATIONS § 850.30 Procedures for Coast Guard investigation. (a) The Coast Guard conducts an investigation...

  2. 33 CFR 23.12 - Coast Guard identifying insignia.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard identifying insignia. 23.12 Section 23.12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.12 Coast Guard identifying...

  3. 33 CFR 52.42 - Views of the Coast Guard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Views of the Coast Guard. 52.42 Section 52.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Submissions by the Coast Guard and Other...

  4. 46 CFR 50.10-25 - Coast Guard Symbol.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard Symbol means that impression stamped on the...

  5. The U.S. Coast Guard Academy Curricula; An Evaluation.

    ERIC Educational Resources Information Center

    Powers, Theodore R.; And Others

    This report presents the results of research that had as its objective the evaluation of the curricula of the U.S. Coast Guard Academy. Over 125 Coast Guard officers and men were interviewed to gather detailed background information about the Coast Guard, the Coast Guard Academy, and job requirements of Academy graduates. These data were developed…

  6. 33 CFR 23.10 - Coast Guard emblem.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Coast Guard emblem. 23.10 Section 23.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The...

  7. 33 CFR 173.83 - Availability of Coast Guard forms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Availability of Coast Guard forms. 173.83 Section 173.83 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Number § 173.83 Availability of Coast Guard forms. In a State where the Coast Guard is the...

  8. 33 CFR 23.20 - Coast Guard commission pennant.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Coast Guard commission pennant. 23.20 Section 23.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.20 Coast Guard commission...

  9. 33 CFR 23.20 - Coast Guard commission pennant.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Coast Guard commission pennant. 23.20 Section 23.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.20 Coast Guard commission...

  10. 46 CFR 50.10-25 - Coast Guard Symbol.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard...

  11. 46 CFR 50.10-25 - Coast Guard Symbol.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard...

  12. 49 CFR 850.30 - Procedures for Coast Guard investigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Procedures for Coast Guard investigation. 850.30... TRANSPORTATION SAFETY BOARD COAST GUARD-NATIONAL TRANSPORTATION SAFETY BOARD MARINE CASUALTY INVESTIGATIONS § 850.30 Procedures for Coast Guard investigation. (a) The Coast Guard conducts an investigation...

  13. 46 CFR 50.10-25 - Coast Guard Symbol.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard...

  14. 49 CFR 850.30 - Procedures for Coast Guard investigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Procedures for Coast Guard investigation. 850.30... TRANSPORTATION SAFETY BOARD COAST GUARD-NATIONAL TRANSPORTATION SAFETY BOARD MARINE CASUALTY INVESTIGATIONS § 850.30 Procedures for Coast Guard investigation. (a) The Coast Guard conducts an investigation...

  15. 46 CFR 50.10-30 - Coast Guard number.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Coast Guard number. 50.10-30 Section 50.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-30 Coast Guard number. (a) The Coast Guard number means that number assigned to boilers and...

  16. 33 CFR 52.42 - Views of the Coast Guard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Views of the Coast Guard. 52.42 Section 52.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Submissions by the Coast Guard and Other...

  17. 33 CFR 173.83 - Availability of Coast Guard forms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Availability of Coast Guard forms. 173.83 Section 173.83 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Number § 173.83 Availability of Coast Guard forms. In a State where the Coast Guard is the...

  18. 33 CFR 173.83 - Availability of Coast Guard forms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Availability of Coast Guard forms. 173.83 Section 173.83 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Number § 173.83 Availability of Coast Guard forms. In a State where the Coast Guard is the...

  19. 49 CFR 850.30 - Procedures for Coast Guard investigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Procedures for Coast Guard investigation. 850.30... TRANSPORTATION SAFETY BOARD COAST GUARD-NATIONAL TRANSPORTATION SAFETY BOARD MARINE CASUALTY INVESTIGATIONS § 850.30 Procedures for Coast Guard investigation. (a) The Coast Guard conducts an investigation...

  20. 46 CFR 50.10-30 - Coast Guard number.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Coast Guard number. 50.10-30 Section 50.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-30 Coast Guard number. (a) The Coast Guard number...

  1. 33 CFR 173.83 - Availability of Coast Guard forms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Availability of Coast Guard forms. 173.83 Section 173.83 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Number § 173.83 Availability of Coast Guard forms. In a State where the Coast Guard is the...

  2. 46 CFR 4.03-20 - Coast Guard district.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Coast Guard district. 4.03-20 Section 4.03-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Definitions § 4.03-20 Coast Guard district. A Coast Guard district is one of the...

  3. 46 CFR 50.10-30 - Coast Guard number.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Coast Guard number. 50.10-30 Section 50.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-30 Coast Guard number. (a) The Coast Guard number...

  4. 33 CFR 52.42 - Views of the Coast Guard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Views of the Coast Guard. 52.42 Section 52.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Submissions by the Coast Guard and Other...

  5. 33 CFR 173.83 - Availability of Coast Guard forms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Availability of Coast Guard forms. 173.83 Section 173.83 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Number § 173.83 Availability of Coast Guard forms. In a State where the Coast Guard is the...

  6. 33 CFR 23.20 - Coast Guard commission pennant.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard commission pennant. 23.20 Section 23.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.20 Coast Guard commission...

  7. 46 CFR 4.03-20 - Coast Guard district.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Coast Guard district. 4.03-20 Section 4.03-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Definitions § 4.03-20 Coast Guard district. A Coast Guard district is one of the...

  8. 46 CFR 50.10-30 - Coast Guard number.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Coast Guard number. 50.10-30 Section 50.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-30 Coast Guard number. (a) The Coast Guard number...

  9. 5. AERIAL VIEW TO NORTHEAST OF ENTIRE COAST GUARD AIR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. AERIAL VIEW TO NORTHEAST OF ENTIRE COAST GUARD AIR STATION SAN FRANCISCO. 8X10 black and white silver gelatin print. United States Coast Guard Official Photograph, 12th Coast Guard District, San Francisco. 1960. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

  10. 33 CFR 23.10 - Coast Guard emblem.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Coast Guard emblem. 23.10 Section 23.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The...

  11. 46 CFR 4.03-20 - Coast Guard district.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Coast Guard district. 4.03-20 Section 4.03-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Definitions § 4.03-20 Coast Guard district. A Coast Guard district is one of the...

  12. 46 CFR 50.10-30 - Coast Guard number.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Coast Guard number. 50.10-30 Section 50.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-30 Coast Guard number. (a) The Coast Guard number...

  13. 46 CFR 4.03-20 - Coast Guard district.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Coast Guard district. 4.03-20 Section 4.03-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Definitions § 4.03-20 Coast Guard district. A Coast Guard district is one of the...

  14. 49 CFR 850.30 - Procedures for Coast Guard investigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Procedures for Coast Guard investigation. 850.30... TRANSPORTATION SAFETY BOARD COAST GUARD-NATIONAL TRANSPORTATION SAFETY BOARD MARINE CASUALTY INVESTIGATIONS § 850.30 Procedures for Coast Guard investigation. (a) The Coast Guard conducts an investigation...

  15. 33 CFR 52.42 - Views of the Coast Guard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Views of the Coast Guard. 52.42 Section 52.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Submissions by the Coast Guard and Other...

  16. 33 CFR 23.12 - Coast Guard identifying insignia.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Coast Guard identifying insignia. 23.12 Section 23.12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.12 Coast Guard identifying...

  17. 33 CFR 23.10 - Coast Guard emblem.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Coast Guard emblem. 23.10 Section 23.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The...

  18. 33 CFR 23.20 - Coast Guard commission pennant.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Coast Guard commission pennant. 23.20 Section 23.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.20 Coast Guard commission...

  19. 33 CFR 23.12 - Coast Guard identifying insignia.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Coast Guard identifying insignia. 23.12 Section 23.12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.12 Coast Guard identifying...

  20. 33 CFR 23.10 - Coast Guard emblem.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Coast Guard emblem. 23.10 Section 23.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The...

  1. 46 CFR 50.10-25 - Coast Guard Symbol.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard...

  2. 33 CFR 23.10 - Coast Guard emblem.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard emblem. 23.10 Section 23.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The...

  3. 33 CFR 23.12 - Coast Guard identifying insignia.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Coast Guard identifying insignia. 23.12 Section 23.12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.12 Coast Guard identifying...

  4. FutureCoast: "Listen to your futures"

    NASA Astrophysics Data System (ADS)

    Pfirman, S. L.; Eklund, K.; Thacher, S.; Orlove, B. S.; Diane Stovall-Soto, G.; Brunacini, J.; Hernandez, T.

    2014-12-01

    Two science-arts approaches are emerging as effective means to convey "futurethinking" to learners: systems gaming and experiential futures. FutureCoast exemplifies the latter: by engaging participants with voicemails supposedly leaking from the cloud of possible futures, the storymaking game frames the complexities of climate science in relatable contexts. Because participants make the voicemails themselves, FutureCoast opens up creative ways for people to think about possibly climate-changed futures and personal ways to talk about them. FutureCoast is a project of the PoLAR Partnership with a target audience of informal adult learners primarily reached via mobile devices and online platforms. Scientists increasingly use scenarios and storylines as ways to explore the implications of environmental change and societal choices. Stories help people make connections across experiences and disciplines and link large-scale events to personal consequences. By making the future seem real today, FutureCoast's framework helps people visualize and plan for future climate changes. The voicemails contributed to FutureCoast are spread through the game's intended timeframe (2020 through 2065). Based on initial content analysis of voicemail text, common themes include ecosystems and landscapes, weather, technology, societal issues, governance and policy. Other issues somewhat less frequently discussed include security, food, industry and business, health, energy, infrastructure, water, economy, and migration. Further voicemail analysis is examining: temporal dimensions (salient time frames, short vs. long term issues, intergenerational, etc.), content (adaptation vs. mitigation, challenges vs. opportunities, etc.), and emotion (hopeful, resigned, etc. and overall emotional context). FutureCoast also engaged audiences through facilitated in-person experiences, geocaching events, and social media (Tumblr, Twitter, Facebook, YouTube). Analysis of the project suggests story-based games such as FutureCoast can serve as effective, accessible tools for engaging diverse audiences in thinking and talking about future "what if?" scenarios related to climate change and its impacts.

  5. 33 CFR 334.783 - Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area. 334.783 Section 334.783 Navigation and... RESTRICTED AREA REGULATIONS § 334.783 Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast.... Government vessels include U.S. Coast Guard vessels, Department of Defense vessels, state and local...

  6. 33 CFR 334.783 - Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area. 334.783 Section 334.783 Navigation and... RESTRICTED AREA REGULATIONS § 334.783 Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast.... Government vessels include U.S. Coast Guard vessels, Department of Defense vessels, state and local...

  7. 33 CFR 334.783 - Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area. 334.783 Section 334.783 Navigation and... RESTRICTED AREA REGULATIONS § 334.783 Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast.... Government vessels include U.S. Coast Guard vessels, Department of Defense vessels, state and local...

  8. 33 CFR 334.783 - Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area. 334.783 Section 334.783 Navigation and... RESTRICTED AREA REGULATIONS § 334.783 Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast.... Government vessels include U.S. Coast Guard vessels, Department of Defense vessels, state and local...

  9. 33 CFR 334.783 - Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Guard Base Mobile, Mobile, Alabama, Coast Guard restricted area. 334.783 Section 334.783 Navigation and... RESTRICTED AREA REGULATIONS § 334.783 Arlington Channel, U.S. Coast Guard Base Mobile, Mobile, Alabama, Coast.... Government vessels include U.S. Coast Guard vessels, Department of Defense vessels, state and local...

  10. Climate change sensitivity of the African ivory nut palm, Hyphaene petersiana Klotzsch ex Mart. (Arecaceae) - a keystone species in SE Africa

    NASA Astrophysics Data System (ADS)

    Blach-Overgaard, A.; Svenning, J.-C.; Balslev, H.

    2009-11-01

    Africa is the most vulnerable continent to future climate change. Profound changes are projected for southwestern Africa with increased drying, notably with delayed onset of the rainy season in September-November, and temperature increases in all seasons. The projected climate changes combined with land-use changes are thought to constitute the main threats to biodiversity in the 21st century. To be able to predict the potential impact on biodiversity, it is crucial to achieve a better insight into the controls of contemporary species ranges. Using species distribution modeling, we assessed the climate sensitivity of the key-stone palm species Hyphaene petersiana (African ivory nut palm) in southern Africa. We tested the relative roles of climate vs. non-climatic range-controls and found that climate had a clear effect on the range of H. petersiana and that especially water-related variables (annual precipitation and precipitation driest quarter) were of high importance. Nevertheless, latitude was the overall most dominant variable, reflecting spatial constraints on the continental-scale distribution. Of the remaining non-climatic factors, soil type and human influence were as important as the climatic factors. A future decrease in annual precipitation below 400 mm and hydrological changes towards drier conditions could cause a dramatic decline in H. petersiana populations, while the influence of temperature changes is less clear. The ongoing, unsustainable utilization pressures on this palm species by humans and livestock are likely to exacerbate the negative effect of future climate changes on its populations, especially, given the expected human population increase in Africa.

  11. Hydrocarbon frontier on the East Coast

    SciTech Connect

    Bowman, H.E.; Sheppard, R.C.; Ziegler, D.G.

    1987-10-12

    This article states that numerous buried Mesozoic basins can be found beneath the Atlantic Coastal Plain sediments. A data acquisition program is being done by Teledyne Exploration Company to provide stratigraphically placed seismic reflection profiles across some of the basins. This article describes what Teledyne is doing. The early Mesozoic rift system, a hydrocarbon frontier on the East Coast, provides promise of a major oil and gas producing province stretching 900 miles along the East Coast. Data at hand now give support to the key elements required, namely, source, reservoir, traps, and seal. Technology has improved to where seismic data resolution now distinctly maps attitudes of beds within these basins in spite of the drastic velocity change at the postrift unconformity of the buried basins and man-made noise and population density. With the continuing risk of energy shortfalls either by reserve, supply, or transportation deficiencies, the authors believe the East Coast is a good place to be.

  12. Gulf Coast Clean Energy Application Center

    SciTech Connect

    Dillingham, Gavin

    2013-09-30

    The Gulf Coast Clean Energy Application Center was initiated to significantly improve market and regulatory conditions for the implementation of combined heat and power technologies. The GC CEAC was responsible for the development of CHP in Texas, Louisiana and Oklahoma. Through this program we employed a variety of outreach and education techniques, developed and deployed assessment tools and conducted market assessments. These efforts resulted in the growth of the combined heat and power market in the Gulf Coast region with a realization of more efficient energy generation, reduced emissions and a more resilient infrastructure. Specific t research, we did not formally investigate any techniques with any formal research design or methodology.

  13. Chalk play tops Gulf Coast horizontal scene

    SciTech Connect

    Not Available

    1991-11-18

    This paper reports on horizontal drilling in the Cretaceous Austin chalk of Texas which dominates news of U.S. Gulf Coast horizontal action. In spite of a significant decline in horizontal drilling in Texas-the Texas Railroad Commission reported a 15 unit decline in the number of permits to drill horizontal wells during the third quarter-operators in East and South Texas continue to expand plays and develop new ones. The Cretaceous Bruda may be gaining some respect as a horizontal target in Texas. Elsewhere on the Gulf Coast, Mississippi soon will see more action on the horizontal drilling front.

  14. SOUTH COAST SCHOOL BUS IDLING STUDY

    EPA Science Inventory

    The Natural Resources Defense Council (NRDC) and Coalition for Clean Air (CCA) conducted this study to provide information useful for estimating exposure of children in the South coast air basin to diesel exhaust while buses are loading and unloading at shcool sites. It was foun...

  15. General Education at the Coast Guard Academy.

    ERIC Educational Resources Information Center

    Sanders, William A.

    In seeking the most effective presentation of the liberal arts in curricula such as the heavily technical and professional curricula at the U.S. Coast Guard Academy, which leave little room for general education, general education course design must capture the imagination of students and motivate them for continuing self-education. Development of

  16. Coast Guard's Response to Spilled Oil

    ERIC Educational Resources Information Center

    Ard, R. W., Jr.

    1976-01-01

    The Coast Guard utilizes a number of monitoring detectors, sensors, and techniques to find, recover and identify oil spills. Discussed in this article are in-situ and airborne sensors, systems developed to provide clean-up capability such as air deployable anti-pollution transfer system (ADAPTS), and techniques which will determine the source of a

  17. Human Dimensions of our Estuaries and Coasts

    EPA Science Inventory

    The connection between humans and the sea via the coastal margin is well understood. Many of our major cities are built in the coastal zone, and 44 % of the world’s population lives within 150 km of the coast (United Nations 2014a). This tight connection is driven by the benefits...

  18. 27 CFR 9.104 - South Coast.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false South Coast. 9.104 Section 9.104 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF...). (v) Then southward along the San Bernardino Meridian to the Riverside County-San Diego County...

  19. METRO EAST COAST ASSESSMENT: FINAL ASSESSMENT REPORT

    EPA Science Inventory

    The Metropolitan East Coast Regional Assessment is one of eighteen regional components of The U.S. National Assessment of the Potential Consequences of Climate Variability and Change, organized by the U.S. Global Change Research Program. The goal of each regional assessment is to...

  20. Human Dimensions of our Estuaries and Coasts

    EPA Science Inventory

    The connection between humans and the sea via the coastal margin is well understood. Many of our major cities are built in the coastal zone, and 44 % of the worlds population lives within 150 km of the coast (United Nations 2014a). This tight connection is driven by the benefits...

  1. CONTAMINATION OF ATLANTIC COAST COMMERCIAL SHELLFISH

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shellfish (oysters and/or clams) were obtained from 37 commercial harvesting sites in 12 Atlantic coast states from Maine to Florida and 1 site in New Brunswick, Canada. Gill washings from 25 shellfish at each site were examined by immunofluorescence microscopy (IFA) for oocysts of Cryptosporidium. ...

  2. Coast Guard's Response to Spilled Oil

    ERIC Educational Resources Information Center

    Ard, R. W., Jr.

    1976-01-01

    The Coast Guard utilizes a number of monitoring detectors, sensors, and techniques to find, recover and identify oil spills. Discussed in this article are in-situ and airborne sensors, systems developed to provide clean-up capability such as air deployable anti-pollution transfer system (ADAPTS), and techniques which will determine the source of a…

  3. General Education at the Coast Guard Academy.

    ERIC Educational Resources Information Center

    Sanders, William A.

    In seeking the most effective presentation of the liberal arts in curricula such as the heavily technical and professional curricula at the U.S. Coast Guard Academy, which leave little room for general education, general education course design must capture the imagination of students and motivate them for continuing self-education. Development of…

  4. GULF COAST REGIONAL ASSESSMENT: PROJECT DESCRIPTION

    EPA Science Inventory

    As part of the USGCRP's First National Assessment effort, EPA is sponsoring the Gulf Coast Regional Assessment. Southern University and A&M College and its collaborators are analyzing and evaluating the potential consequences of climate variability and change for the region in th...

  5. 1. General view of guard house and entrance to Coast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view of guard house and entrance to Coast Guard Base from La Putilla Street, looking southwest - U.S. Coast Guard Base, San Juan, Guard House, La Puntilla Finalle, San Juan, San Juan Municipio, PR

  6. 50 CFR 600.1102 - Pacific Coast groundfish fee.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Pacific Coast groundfish fee. 600.1102... Fishing Capacity Reduction Regulations 600.1102 Pacific Coast groundfish fee. (a) Purpose. This section implements the fee for repaying the reduction loan financing the Pacific Coast Groundfish Program...

  7. 50 CFR 600.1102 - Pacific Coast groundfish fee.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Pacific Coast groundfish fee. 600.1102... Fishing Capacity Reduction Regulations 600.1102 Pacific Coast groundfish fee. (a) Purpose. This section implements the fee for repaying the reduction loan financing the Pacific Coast Groundfish Program...

  8. 50 CFR 600.1102 - Pacific Coast groundfish fee.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Pacific Coast groundfish fee. 600.1102... Fishing Capacity Reduction Regulations 600.1102 Pacific Coast groundfish fee. (a) Purpose. This section implements the fee for repaying the reduction loan financing the Pacific Coast Groundfish Program...

  9. USGS with U.S. and Canadian Coast Guard

    USGS Multimedia Gallery

    Waiting to board the Canadian helicopter from U.S. Coast Guard Cutter Healy and visit Canadian Coast Guard Ship Louis S. St. Laurent. From left to right: USGS scientist Jonathan Childs, chief scientist for this expedition on Healy; U.S. Coast Guard Lieutenant Commander Douglas Petrusa; Canadian Coas...

  10. 50. Elevation view underway, showing "new" coast guard paint scheme ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. Elevation view underway, showing "new" coast guard paint scheme and A-frame crane. Note crews quarters expanded over turtle deck at stern. - U.S. Coast Guard Cutter WHITE SUMAC, U.S. Coast Guard 8th District Base, 4640 Urquhart Street, New Orleans, Orleans Parish, LA

  11. 46 CFR 90.10-9 - Coast Guard District Commander.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Coast Guard District Commander. 90.10-9 Section 90.10-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 90.10-9 Coast Guard District Commander. This...

  12. 33 CFR 174.125 - Coast Guard address.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Coast Guard address. 174.125 Section 174.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY STATE NUMBERING AND CASUALTY REPORTING SYSTEMS State Reports § 174.125 Coast Guard...

  13. 46 CFR 14.103 - Addresses of Coast Guard.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Addresses of Coast Guard. 14.103 Section 14.103 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS General § 14.103 Addresses of Coast Guard. (a) U.S. postal mail: U.S....

  14. 33 CFR 100.10 - Coast Guard-State agreements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Coast Guard-State agreements. 100.10 Section 100.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.10 Coast Guard-State agreements....

  15. 46 CFR 107.117 - Coast Guard addresses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Coast Guard addresses. 107.117 Section 107.117 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION General § 107.117 Coast Guard addresses. When approval of the Commandant is required under...

  16. 33 CFR 64.33 - Marking by the Coast Guard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Marking by the Coast Guard. 64.33 Section 64.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Marking by the Coast Guard. (a) The District Commander may mark for the protection of maritime...

  17. 33 CFR 174.125 - Coast Guard address.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Coast Guard address. 174.125 Section 174.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY STATE NUMBERING AND CASUALTY REPORTING SYSTEMS State Reports § 174.125 Coast Guard...

  18. 33 CFR 118.30 - Action by Coast Guard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Action by Coast Guard. 118.30 Section 118.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.30 Action by Coast Guard. (a) The District Commander receiving...

  19. 33 CFR 173.35 - Coast Guard validation sticker.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Coast Guard validation sticker. 173.35 Section 173.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... number issued by the Coast Guard unless it has the validation sticker issued with the certificate...

  20. 33 CFR 118.30 - Action by Coast Guard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Action by Coast Guard. 118.30 Section 118.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.30 Action by Coast Guard. (a) The District Commander receiving...

  1. 33 CFR 66.01-15 - Action by Coast Guard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Action by Coast Guard. 66.01-15 Section 66.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Coast Guard. (a) The District Commander receiving the application will review it for completeness...

  2. 33 CFR 66.01-15 - Action by Coast Guard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Action by Coast Guard. 66.01-15 Section 66.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Coast Guard. (a) The District Commander receiving the application will review it for completeness...

  3. 46 CFR 14.103 - Addresses of Coast Guard.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Addresses of Coast Guard. 14.103 Section 14.103 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS General § 14.103 Addresses of Coast Guard. (a) U.S. postal mail: U.S....

  4. 33 CFR 174.125 - Coast Guard address.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Coast Guard address. 174.125 Section 174.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY STATE NUMBERING AND CASUALTY REPORTING SYSTEMS State Reports § 174.125 Coast Guard...

  5. 33 CFR 100.10 - Coast Guard-State agreements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Coast Guard-State agreements. 100.10 Section 100.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.10 Coast Guard-State agreements....

  6. 33 CFR 64.33 - Marking by the Coast Guard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Marking by the Coast Guard. 64.33 Section 64.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Marking by the Coast Guard. (a) The District Commander may mark for the protection of maritime...

  7. 33 CFR 66.01-15 - Action by Coast Guard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Action by Coast Guard. 66.01-15 Section 66.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Coast Guard. (a) The District Commander receiving the application will review it for completeness...

  8. 1. AERIAL VIEW TO WEST OF COAST GUARD AIR STATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. AERIAL VIEW TO WEST OF COAST GUARD AIR STATION SAN FRANCISCO, SHOWING ALL MAJOR BUILDINGS. 8X10 black and white silver gelatin print. United States Coast Guard, February 1962. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

  9. 46 CFR 14.103 - Addresses of Coast Guard.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Addresses of Coast Guard. 14.103 Section 14.103 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS General § 14.103 Addresses of Coast Guard. (a) U.S. postal mail: U.S....

  10. 46 CFR 167.05-15 - Coast Guard District Commander.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Coast Guard District Commander. 167.05-15 Section 167.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-15 Coast Guard District Commander. This term means an officer of...

  11. 33 CFR 118.30 - Action by Coast Guard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Action by Coast Guard. 118.30 Section 118.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.30 Action by Coast Guard. (a) The District Commander receiving...

  12. 28. VIEW OF WHITE SAGE PRIOR TO BEING PAINTED COAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. VIEW OF WHITE SAGE PRIOR TO BEING PAINTED COAST GUARD COLORS OF BLACK AND WHITE. NOTE ALSO THE PHOTOGRAPH WAS TAKEN PRIOR TO THE INSTALLATION OF A-FRAME MAST AND BOOM AND TO THE CONSTRUCTION OF TURTLE DECK. - U.S. Coast Guard Cutter WHITE SAGE, U.S. Coast Guard 1st District Base, 1 Thames Street, Bristol, Bristol County, RI

  13. 33 CFR 100.10 - Coast Guard-State agreements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Coast Guard-State agreements. 100.10 Section 100.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.10 Coast Guard-State agreements....

  14. 46 CFR 14.103 - Addresses of Coast Guard.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Addresses of Coast Guard. 14.103 Section 14.103 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS General § 14.103 Addresses of Coast Guard. (a) U.S. postal mail: U.S....

  15. 46 CFR 14.103 - Addresses of Coast Guard.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Addresses of Coast Guard. 14.103 Section 14.103 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS General § 14.103 Addresses of Coast Guard. (a) U.S. postal mail: U.S....

  16. 46 CFR 167.05-15 - Coast Guard District Commander.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Coast Guard District Commander. 167.05-15 Section 167.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-15 Coast Guard District Commander. This term means an officer of...

  17. 33 CFR 64.33 - Marking by the Coast Guard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Marking by the Coast Guard. 64.33 Section 64.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Marking by the Coast Guard. (a) The District Commander may mark for the protection of maritime...

  18. 46 CFR 167.05-15 - Coast Guard District Commander.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Coast Guard District Commander. 167.05-15 Section 167.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-15 Coast Guard District Commander. This term means an officer of...

  19. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  20. 33 CFR 64.33 - Marking by the Coast Guard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Marking by the Coast Guard. 64.33 Section 64.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Marking by the Coast Guard. (a) The District Commander may mark for the protection of maritime...

  1. 46 CFR 107.117 - Coast Guard addresses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Coast Guard addresses. 107.117 Section 107.117 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION General § 107.117 Coast Guard addresses. When approval of the Commandant is required under...

  2. 33 CFR 64.33 - Marking by the Coast Guard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Marking by the Coast Guard. 64.33 Section 64.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Marking by the Coast Guard. (a) The District Commander may mark for the protection of maritime...

  3. 33 CFR 118.30 - Action by Coast Guard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Action by Coast Guard. 118.30 Section 118.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.30 Action by Coast Guard. (a) The District Commander receiving...

  4. Family moves and depression among Coast Guard wives.

    PubMed

    McGarigal, Alyssa; Jablonski, Jessica; Ferri, Christine; Lester, David

    2009-12-01

    A comparison of 78 Coast Guard wives' and 30 firefighters' wives' scores on Zung's self-rating scale for depression showed no differences, but the Coast Guard wives had more often been prescribed antidepressants. Scores on a scale to assess the negative effects of moving were positively associated with current depression for the Coast Guard wives. PMID:20099556

  5. 33 CFR 100.10 - Coast Guard-State agreements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Coast Guard-State agreements. 100.10 Section 100.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.10 Coast Guard-State agreements....

  6. 46 CFR 167.05-15 - Coast Guard District Commander.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Coast Guard District Commander. 167.05-15 Section 167.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-15 Coast Guard District Commander. This term means an officer of...

  7. 46 CFR 167.05-15 - Coast Guard District Commander.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Coast Guard District Commander. 167.05-15 Section 167.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Definitions § 167.05-15 Coast Guard District Commander. This term means an officer of...

  8. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  9. 33 CFR 100.10 - Coast Guard-State agreements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard-State agreements. 100.10 Section 100.10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.10 Coast Guard-State agreements....

  10. 46 CFR 107.117 - Coast Guard addresses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Coast Guard addresses. 107.117 Section 107.117 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION General § 107.117 Coast Guard addresses. When approval of the Commandant is required under...

  11. 46 CFR 90.10-9 - Coast Guard District Commander.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Coast Guard District Commander. 90.10-9 Section 90.10-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 90.10-9 Coast Guard District Commander. This...

  12. 4. AERIAL VIEW TO SOUTHEAST OF ENTIRE COAST GUARD AIR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. AERIAL VIEW TO SOUTHEAST OF ENTIRE COAST GUARD AIR STATION SAN FRANCISCO. 8X10 black and white silver gelatin print. United States Coast Guard Official Photograph, 12th District, File No. 62751-22 A.S. Date unknown. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

  13. 33 CFR 173.35 - Coast Guard validation sticker.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Coast Guard validation sticker. 173.35 Section 173.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... number issued by the Coast Guard unless it has the validation sticker issued with the certificate...

  14. 46 CFR 90.10-9 - Coast Guard District Commander.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Coast Guard District Commander. 90.10-9 Section 90.10-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 90.10-9 Coast Guard District Commander. This...

  15. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  16. 2. AERIAL VIEW TO SOUTHEAST OF COAST GUARD AIR STATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. AERIAL VIEW TO SOUTHEAST OF COAST GUARD AIR STATION SAN FRANCISCO, SHOWING ALL MAJOR BUILDINGS. 8X10 black and white silver gelatin print. United States Coast Guard, February 1962. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

  17. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  18. 46 CFR 107.117 - Coast Guard addresses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Coast Guard addresses. 107.117 Section 107.117 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION General § 107.117 Coast Guard addresses. When approval of the Commandant is required under...

  19. 33 CFR 173.35 - Coast Guard validation sticker.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Coast Guard validation sticker. 173.35 Section 173.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... number issued by the Coast Guard unless it has the validation sticker issued with the certificate...

  20. 33 CFR 174.125 - Coast Guard address.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Coast Guard address. 174.125 Section 174.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY STATE NUMBERING AND CASUALTY REPORTING SYSTEMS State Reports § 174.125 Coast Guard...