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Sample records for african gaboon viper

  1. [Some African gregarines (Ivory Coast, Gaboon) (author's transl)].

    PubMed

    Théodoridès, J; Desportes, I; Mateu, J

    1976-01-01

    We study in the present paper two collections of Gregarines (all parasite of terrestrial arthropods) from the Ivory Coast and the Gaboon. Among the 17 species studied, three are new for science: Gregarina darchenae, Gregarina pycnoceri and Gigaductus africanus. The other species have been already found in closely related hosts.

  2. Viral Association with the Elusive Rickettsia of Viper Plague from Ghana, West Africa

    DTIC Science & Technology

    2008-12-01

    quently infected and killed at least 22 snakes , in- cluding Gaboon vipers, rhinoceros vipers (Bitis nasicornis), a Sri Lankan cobra (Naja naja polycel...lata), a monocellate cobra (Naja naja kaouthia), a black-necked cobra (Naja nigricollis), and bull- snakes (Pituophis melanoleucus sayi). The out...arrows) in Russell’s viper spleen cells (VSW; A and B) and heart cells (VH2; C), infected with serum from bull snake , and in bovine endothelial cells

  3. Emerging tick-borne disease in African vipers caused by a Cowdria-like organism.

    PubMed

    Kiel, Johnathan L; Alarcon, Rodolfo M; Parker, Jill E; Vivekananda, Jeeva; Gonzalez, Yvette B; Stribling, Lucille J V; Andrews, Carrie J

    2006-10-01

    Heartwater is a tick-borne infectious disease caused by the rickettsial organism Cowdria ruminantium, currently Ehrlichia ruminantium. It poses an imminent threat to the Western Hemisphere, where it could cause mortality in cattle and other ruminant livestock in excess of 70%. It has been reported in the Caribbean; and its vector, Amblyomma sparsum, has been found on imported African spurred tortoises (Geochelone sulcata) and leopard tortoises (Geochelone pardalis) in southern Florida in the United States, leading to an importation ban on these reptiles. Symptoms have not been previously reported in reptiles. Here, we report peracute and acute deaths in African vipers imported from Africa through Florida. Signs included vomiting mucoid fluid, diarrhea, emaciation, convulsions, and death. Postmortem showed few gross lesions. The most consistent peracute and acute lesions were the pulmonary lesions and pericarditis with considerable bloody fluid in the pericardial sac (hydropericardium). These lesions strongly resembled the lesions of heartwater and a coccobacillus of less than 1-micron diameter was isolated in viper cell culture. The outbreak was brought to a halt by tick control and treatment of all exposed snakes with tetracycline. This isolation, tetracycline sensitivity, clinical signs, preliminary results with polymerase chain reaction of pCS20 ORF, and the viper preference of the disease may indicate a Cowdria-related attenuated species that has adapted to infect reptiles or an emerging new form of this group of microbes.

  4. Characterization of a new polyvalent antivenom (Antivipmyn Africa) against African vipers and elapids.

    PubMed

    Ramos-Cerrillo, Blanca; de Roodt, Adolfo R; Chippaux, Jean-Philippe; Olguín, Laura; Casasola, Andrea; Guzmán, Guadalupe; Paniagua-Solís, Jorge; Alagón, Alejandro; Stock, Roberto P

    2008-12-15

    As a response to the antivenom shortage in Sub-Saharan Africa, evident for well over a decade, we developed a new polyvalent anti-ophidian antivenom (Antivipmyn((R)) Africa) designed for use in the region. We report a detailed characterization of its biochemical composition (protein content and profiling by size-exclusion chromatography and electrophoresis) as well as the specific and para-specific neutralization potencies (as median effective dose in the mouse lethality test). Additionally, we studied the neutralization of hemorrhagic, anti-hemostatic and necrotic activities of Echis ocellatus venom, responsible for a majority of severe envenomations in the continent according to existing epidemiological data. The antivenom is currently under production and has already been employed in the field in a pragmatic Phase III clinical trial in the Republic of Benin. It is a purified lyophilized polyvalent equine F(ab')(2)-based product obtained by immunization with the venoms of eleven species of African snakes of the Genera Echis, Bitis, Naja and Dendroaspis. The criteria for its design are discussed, particularly in terms of the implementation of realistic public health policies targeting mostly rural populations in the continent.

  5. Evolutionary relationships among cyst-forming coccidia Sarcocystis spp. (Alveolata: Apicomplexa: Coccidea) in endemic African tree vipers and perspective for evolution of heteroxenous life cycle.

    PubMed

    Slapeta, Jan R; Modrý, David; Votýpka, Jan; Jirků, Milan; Lukes, Julius; Koudela, Bretislav

    2003-06-01

    Cyst-forming coccidia of the genus Sarcocystis (Alveolata: Apicomplexa: Coccidea) parasitize vertebrates worldwide. Data from the small subunit rRNA genes (SSU) and the D2 domain of the large subunit rRNA genes were used to reconstruct phylogeny for all species in the Sarcocystidae for which sequences are currently available. We have focused on the evolutionary history of species that circulate between snakes as definitive hosts and rodents as intermediate hosts. Trees were reconstructed using maximum parsimony, minimum evolution, maximum likelihood and the bayesian phylogenetics. Our reconstructions support monophyly of Sarcocystidae but fail to robustly resolve the relationship within clades. Using a concatenated dataset of available rDNAs, the "isosporoid" coccidia Neospora, Toxoplasma, Besnoitia, Isospora and Hyaloklossia form a sister group to the monophyletic Sarcocystis. Moreover, we show that Sarcocystis from arboreal vipers of the genus Atheris, which are endemic to the mountain rain forests of the Equatorial Africa, are monophyletic, with sister species parasitizing the desert viper Pseudocerastes persicus from the Near East. We report the co-evolution of Sarcocystis spp. with their final snake hosts. The geological history of the African continent, mountain ranges, forests and general SSU rDNA rates were used to construct a linearized tree. Possible origin of the heteroxenous life cycle of Sarcocystis is discussed.

  6. VIPER project

    NASA Technical Reports Server (NTRS)

    Kershaw, John

    1990-01-01

    The VIPER project has so far produced a formal specification of a 32 bit RISC microprocessor, an implementation of that chip in radiation-hard SOS technology, a partial proof of correctness of the implementation which is still being extended, and a large body of supporting software. The time has now come to consider what has been achieved and what directions should be pursued in the future. The most obvious lesson from the VIPER project was the time and effort needed to use formal methods properly. Most of the problems arose in the interfaces between different formalisms, e.g., between the (informal) English description and the HOL spec, between the block-level spec in HOL and the equivalent in ELLA needed by the low-level CAD tools. These interfaces need to be made rigorous or (better) eliminated. VIPER 1A (the latest chip) is designed to operate in pairs, to give protection against breakdowns in service as well as design faults. We have come to regard redundancy and formal design methods as complementary, the one to guard against normal component failures and the other to provide insurance against the risk of the common-cause failures which bedevil reliability predictions. Any future VIPER chips will certainly need improved performance to keep up with increasingly demanding applications. We have a prototype design (not yet specified formally) which includes 32 and 64 bit multiply, instruction pre-fetch, more efficient interface timing, and a new instruction to allow a quick response to peripheral requests. Work is under way to specify this device in MIRANDA, and then to refine the spec into a block-level design by top-down transformations. When the refinement is complete, a relatively simple proof checker should be able to demonstrate its correctness. This paper is presented in viewgraph form.

  7. Snake bite: pit vipers.

    PubMed

    Peterson, Michael E

    2006-11-01

    Pit vipers are the largest group of venomous snakes in the United States and are involved in an estimated 150,000 bites annually of dogs and cats. The severity of any pit viper bite is related to the volume and toxicity of the venom injected as well as the location of the bite, which may influence the rate of venom uptake. The toxicity of rattlesnake venom varies widely. It is possible for pit vipers' venom to be strictly neurotoxic with virtually no local signs of envenomation. Venom consists of 90% water and has a minimum of 10 enzymes and 3 to 12 nonenzymatic proteins and peptides in any individual snake. The onset of clinical signs after envenomation may be delayed for several hours. The presence of fang marks does not indicate that envenomation has occurred, only that a bite has taken place. Systemic clinical manifestations encompass a wide variety of problems including pain, weakness, dizziness, nausea, severe hypotension, and thrombocytopenia. The victim's clotting abnormalities largely depend upon the species of snake involved. Venom induced thrombocytopenia occurs in approximately 30% of envenomations. Many first aid measures have been advocated for pit viper bite victims, none has been shown to prevent morbidity or mortality. Current recommendations for first aid in the field are to keep the victim calm, keep the bite site below heart level if possible, and transport the victim to a veterinary medical facility for primary medical intervention. The patient should be hospitalized and monitored closely for a minimum of 8 hours for the onset of signs of envenomation. The only proven specific therapy against pit viper envenomation is the administration of antivenin. The dosage of antivenin needed is calculated relative to the amount of venom injected, the body mass of the victim, and the bite site. The average dosage in dogs and cats is 1 to 2 vials of antivenin.

  8. Viper. [Design modification

    NASA Technical Reports Server (NTRS)

    Gilbert, L. E. Paul; Berry, Cassie; Lamborn, Dana; Murphy, Jack; Okelly, Chris

    1993-01-01

    A Viper aircraft was redesigned with a new airfoil and engine to verify if improvements can be made to the baseline configuration. The two major redesigning processes were: replacing the baseline aircraft's NACA 652-415 airfoil with an NLF 0414 Natural Laminar Flow airfoil, and the baseline aircraft's Lycoming 0-235 engine with a Teledyne Continental GR-36 rotary combustion engine. As a result of these changes: (1) the Viper aircraft becomes smaller in most respects (gross weight, wing platform area, and horizontal tail area); (2) overall drag of the aircraft decreased (due to reduction in area and the reduced drug of the new airfoil); (3) cruise velocity, the maximum rate of climb at sea level, and takeoff distance (but not landing distance) decreased; and (4) cost increased. Although the overall drag decreased, the performance remained about the same due to the reduced horsepower available from the Teledyne Continental engine.

  9. Taming the Viper: Software Upgrade for VFAUser and Viper

    SciTech Connect

    DORIN,RANDALL T.; MOSER III,JOHN C.

    2000-08-08

    This report describes the procedure and properties of the software upgrade for the Vibration Performance Recorder. The upgrade will check the 20 memory cards for proper read/write operation. The upgrade was successfully installed and uploaded into the Viper and the field laptop. The memory checking routine must run overnight to complete the test, although the laptop need only be connected to the Viper unit until the downloading routine is finished. The routine has limited ability to recognize incomplete or corrupt header and footer files. The routine requires 400 Megabytes of free hard disk space. There is one minor technical flaw detailed in the conclusion.

  10. Comparison of the adjuvant activity of emulsions with different physicochemical properties on the antibody response towards the venom of West African carpet viper (Echis ocellatus).

    PubMed

    Valverde, Juan Manuel; Rodríguez, Karina; Herrera, María; Segura, Álvaro; Vargas, Mariángela; Villalta, Mauren; Montero, Mavis; Gutiérrez, Jose María; León, Guillermo

    2017-03-01

    Adjuvant emulsions are widely used to enhance the antibody response of the animals used as immunoglobulin source for producing antivenoms. Usually, the adjuvant activity of emulsions is attributed both to their ability to trigger "danger" signals from cells in which they induce death, and to form depots from which immunogens are slowly released. However, there is contradictory evidence suggesting that adjuvant activity of emulsions is independent of the dispersion type and the rate of immunogen release. In order to test how physical properties of emulsions, composed of mineral oil and water, affect their ability to enhance the antibody response towards snake venoms, we compared water-in-oil (W/O) emulsions prepared at volume ratios of 70/30, 50/50 or 30/70, a 50/50 oil-in-water (O/W) emulsion, and a water-in-oil-in-water (W/O/W) multiple emulsion. Comparison included their droplet-size, viscosity, rate of immunogen release and ability to enhance the antibody response of mice immunized with the venom of the African viperid snake Echis ocellatus. It was found that all emulsions released a low amount of venom, and that the 50/50 (W/O) and the multiple emulsion (W/O/W) were those that induced the higher anti-venom antibody response. Our results suggest that the ability of emulsions to enhance the anti-venom response is not associated to their ability to form depots from which the venom is slowly released.

  11. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Russell viper venom reagent. 864.8950 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper venom reagent is a device used to determine the cause of...

  12. Lessons Learned from Pit Viper System Deployment

    SciTech Connect

    Catalan, Michael A.; Bailey, Sharon A.; Alzheimer, James M.; Baker, Carl P.; Valdez, Patrick L.

    2002-08-08

    The Pit Viper is a tele-operated system intended to enhance worker safety while simultaneously improving the efficiency of pit operations at the Hanford Site. Commercial off-the-shelf (COTS) components were used in an attempt to increase system reliability and reduce integration difficulties. The Pit Viper, as is, provides significant improvement over the current baseline approach. During integration, multiple areas where technology development would enhance the effectiveness of the system were identified. Most notable of these areas were the manipulator control system, tool design, and tool handling. Various issues were identified regarding the interfacing of the Pit Viper with the Tank Farm environment and the maturity of remote/ robotic systems for unstructured environments.

  13. Predator facilitation or interference: a game of vipers and owls.

    PubMed

    Embar, Keren; Raveh, Ashael; Hoffmann, Ishai; Kotler, Burt P

    2014-04-01

    In predator-prey foraging games, the prey's reaction to one type of predator may either facilitate or hinder the success of another predator. We ask, do different predator species affect each other's patch selection? If the predators facilitate each other, they should prefer to hunt in the same patch; if they interfere, they should prefer to hunt alone. We performed an experiment in a large outdoor vivarium where we presented barn owls (Tyto alba) with a choice of hunting greater Egyptian gerbils (Gerbillus pyramidum) in patches with or without Saharan horned vipers (Cerastes cerastes). Gerbils foraged on feeding trays set under bushes or in the open. We monitored owl location, activity, and hunting attempts, viper activity and ambush site location, and the foraging behavior of the gerbils in bush and open microhabitats. Owls directed more attacks towards patches with vipers, and vipers were more active in the presence of owls. Owls and vipers facilitated each other's hunting through their combined effect on gerbil behavior, especially on full moon nights when vipers are more active. Owls forced gerbils into the bushes where vipers preferred to ambush, while viper presence chased gerbils into the open where they were exposed to owls. Owls and vipers took advantage of their indirect positive effect on each other. In the foraging game context, they improve each other's patch quality and hunting success.

  14. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper...

  15. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper...

  16. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper...

  17. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper...

  18. VIPERS: Galaxy morphology at z ˜ 1

    NASA Astrophysics Data System (ADS)

    Krywult, Janusz; Pollo, Agnieszka; Vipers Team

    2014-12-01

    We use spectroscopic VIPERS data to analyze morphological properties of galaxies at z ˜ 1. To determine galaxy morphologies, we estimate their Sérsic index. Then, we correlate it with galaxy rest-frame colors, and other physical properties. We find that the distribution of Sérsic index of our sample is bimodal, and well correlated with the color-bimodality of the galaxy distribution. So-called green valley (i.e. intermediate colour) galaxies often have intermediate values of Sérsic index which may support the hypothesis that at least a part of this population are galaxies in the transition phase.

  19. Morphology and evolution of VIPERS galaxies

    NASA Astrophysics Data System (ADS)

    Krywult, Janusz; Pollo, Agnieszka

    2016-06-01

    Using the spectroscopic and photometric data from the VIMOS Public Extragalactic Redshift Survey (VIPERS), together with the CFHTLS T0006 CCD images, we analyze co-evolution of rest-frame colours and Sérsic indices of the early and late-type galaxies in the redshift range 0.5 < z < 1.0. We find a strong Gaussian bimodality of both the galaxy rest-frame colour and Sérsic index distribution in the redshift - luminosity plane. We propose a new empirical model of galaxy colour and Sérsic index dependence on redshift and luminosity, to study the dynamical and chemical evolution of galaxies.

  20. Genomic and phylogenetic evidence of VIPER retrotransposon domestication in trypanosomatids

    PubMed Central

    Ludwig, Adriana; Krieger, Marco Aurelio

    2016-01-01

    Transposable elements are important residents of eukaryotic genomes and eventually the host can domesticate them to serve cellular functions. We reported here a possible domestication event of the vestigial interposed retroelement (VIPER) in trypanosomatids. We found a large gene in a syntenic location in Leishmania braziliensis, L. panamensis, Leptomanas pyrrhocoris, and Crithidia fasciculata whose products share similarity in the C-terminal portion with the third protein of VIPER. No remnants of other VIPER regions surrounding the gene sequence were found. We hypothesise that the domestication event occurred more than 50 mya and the conservation of this gene suggests it might perform some function in the host species. PMID:27849219

  1. VIPER: Virtual Intelligent Planetary Exploration Rover

    NASA Technical Reports Server (NTRS)

    Edwards, Laurence; Flueckiger, Lorenzo; Nguyen, Laurent; Washington, Richard

    2001-01-01

    Simulation and visualization of rover behavior are critical capabilities for scientists and rover operators to construct, test, and validate plans for commanding a remote rover. The VIPER system links these capabilities. using a high-fidelity virtual-reality (VR) environment. a kinematically accurate simulator, and a flexible plan executive to allow users to simulate and visualize possible execution outcomes of a plan under development. This work is part of a larger vision of a science-centered rover control environment, where a scientist may inspect and explore the environment via VR tools, specify science goals, and visualize the expected and actual behavior of the remote rover. The VIPER system is constructed from three generic systems, linked together via a minimal amount of customization into the integrated system. The complete system points out the power of combining plan execution, simulation, and visualization for envisioning rover behavior; it also demonstrates the utility of developing generic technologies. which can be combined in novel and useful ways.

  2. VIPERS: Stellar population properties of early-type galaxies

    NASA Astrophysics Data System (ADS)

    Siudek, Małgorzata; Malek, Katarzyna; Garilli, Bianka; Scodeggio, Marco; Fritz, Alexander; Pollo, Agnieszka

    2016-06-01

    We present stellar population properties of early-type galaxies from the VIMOS Public Extragalactic Redshift Survey (VIPERS) based on the spectral measurements of ˜ 4000 galaxies with stellar masses from 10^{10} to 10^{12} {[M_{⊙}]} in the redshift range 0.4 < z < 1.0. We quantify relations between their age, stellar metallicity, duration of star burst, and stellar mass. We compare the properties of VIPERS intermediate redshift galaxies with galaxies found in the Local Universe.

  3. Antipredatory function of head shape for vipers and their mimics.

    PubMed

    Valkonen, Janne K; Nokelainen, Ossi; Mappes, Johanna

    2011-01-01

    Most research into the adaptive significance of warning signals has focused on the colouration and patterns of prey animals. However, behaviour, odour and body shape can also have signal functions and thereby reduce predators' willingness to attack defended prey. European vipers all have a distinctive triangular head shape; and they are all venomous. Several non-venomous snakes, including the subfamily Natricinae, commonly flatten their heads (also known as head triangulation) when disturbed. The adaptive significance of this potential behavioural mimicry has never been investigated.We experimentally tested if the triangular head shape typical of vipers offers protection against predation. We compared the predation pressure of free-ranging predators on artificial snakes with triangular-shaped heads against the pressure on replicas with narrow heads. Snakes of both head types had either zigzag patterned bodies, typical of European vipers, or plain (patternless) bodies. Plain snakes with narrower Colubrid-like heads suffered significantly higher predation by raptors than snakes with triangular-shaped heads. Head shape did not, however, have an additive effect on survival in zigzag-patterned snakes, suggesting that species which differ from vipers in colouration and pattern would benefit most from behavioural mimicry. Our results demonstrate that the triangular head shape typical of vipers can act as a warning signal to predators. We suggest that head-shape mimicry may be a more common phenomenon among more diverse taxa than is currently recognised.

  4. Palestine Saw-scaled Vipers hunt disadvantaged avian migrants.

    PubMed

    Yosef, Reuven; Zduniak, Piotr

    2015-11-01

    The selection of an ambush-cum-foraging site and proper prey are indispensable for maintaining an adequate energy intake by sit-and-wait predators to optimize survival and future fitness. This is important for snakes, where an ambush site has suitable ambience. We studied the foraging strategy of the Palestine Saw-scaled Viper (Echis coloratus) at an avian migratory stopover site. Following initial observations, we hypothesized that vipers are able to discern the body mass of a perched bird and hunt accordingly. We implemented an experiment where vipers chose between four groups of migratory Blackcaps with different body mass. Prey choice by vipers of both age classes was not random and adults focused on Blackcaps with the lightest body mass. Juveniles displayed a variability of prey choice but selected mainly birds from the lightest categories. We concluded that Saw-scaled Vipers hunt prey based on thermal cues; juveniles practice on different prey groups prior to perfecting their foraging techniques i.e., hunting is a learned process; and that they prefer birds with the lowest body mass. The last because Blackcaps, when on migration, save energy by entering a state of deep torpor in which they sacrifice their vigilance capabilities.

  5. Debunking the viper's strike: harmless snakes kill a common assumption.

    PubMed

    Penning, David A; Sawvel, Baxter; Moon, Brad R

    2016-03-01

    To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move.

  6. Debunking the viper's strike: harmless snakes kill a common assumption

    PubMed Central

    Sawvel, Baxter; Moon, Brad R.

    2016-01-01

    To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. PMID:26979562

  7. Report on the formal specification and partial verification of the VIPER microprocessor

    NASA Technical Reports Server (NTRS)

    Brock, Bishop; Hunt, Warren A., Jr.

    1991-01-01

    The formal specification and partial verification of the VIPER microprocessor is reviewed. The VIPER microprocessor was designed by RSRE, Malvern, England, for safety critical computing applications (e.g., aircraft, reactor control, medical instruments, armaments). The VIPER was carefully specified and partially verified in an attempt to provide a microprocessor with completely predictable operating characteristics. The specification of VIPER is divided into several levels of abstraction, from a gate-level description up to an instruction execution model. Although the consistency between certain levels was demonstrated with mechanically-assisted mathematical proof, the formal verification of VIPER was never completed.

  8. Factors influencing habitat selection by arboreal pit vipers.

    PubMed

    Sawant, Nitin S; Jadhav, Trupti D

    2013-01-01

    We studied factors influencing habitat selection by two arboreal species of pit viper, namely Trimeresurus malabaricus (Malabar pit viper) and T. gramineus (Bamboo pit viper). The macrohabitat of these species was classified as forest, forest edge, or open habitat. To determine microhabitat selection, a variety of features at every other snake location were measured. Whether or not the animal was found in a tree, the tree species, its height of perch, position on the branch (distal/ apical/middle), diameter of the branch, the tree canopy (thick/sparse) and vegetation of the area (thick/sparse) were recorded. Assessment of habitat was done to determine how patterns of habitat use vary seasonally. Shaded ambient (air) temperatures and humidity were recorded. Data pertaining to 90 individuals of T. malabaricus and 100 individuals of T. gramineus were recorded. Trimeresurus malabaricus selected home ranges that included areas with thick vegetation and were encountered at regions of higher altitude. Neither of the species was found in open habitats. Both of the species preferred diverse habitats and were spread over the entire available space during the monsoon; they did not show any preference for the perch height during different seasons. Males had a positive correlation between body mass and preferred perch diameter. The present study suggests that several factors play an important role in habitat selection by these arboreal pit vipers, thus making them highly habitat-specific.

  9. [Infections and deaths of horned vipers, Cerastes cerastes (L., 1758) and lebetin vipers, Vipera lebetina (L., 1758) caused by Pseudomonas aeruginosa (Schröeter, 1885)].

    PubMed

    Slavtchev, R S; Chadli, A

    1984-12-01

    The authors present some data about the buccal and intestinal microflora of Ophidian Reptiles schooling in the vivaria of the Institute Pasteur of Tunis. They describe two cases of infestation and dead, chiefly symptomatology, of a horned Viper, Cerastes cerastes (L. 1758) and a lebetin Viper, Vipera lebetina (L., 1758) by Pseudomonas aeruginosa Schröeter, 1885.

  10. A case study for the real-time experimental evaluation of the VIPER microprocessor

    NASA Technical Reports Server (NTRS)

    Carreno, Victor A.; Angellatta, Rob K.

    1991-01-01

    An experiment to evaluate the applicability of the Verifiable Integrated Processor for Enhanced Reliability (VIPER) microprocessor to real time control is described. The VIPER microprocessor was invented by the Royal Signals and Radar Establishment (RSRE), U.K., and is an example of the use of formal mathematical methods for developing electronic digital systems with a high degree of assurance on the system design and implementation correctness. The experiment consisted of selecting a control law, writing the control law algorithm for the VIPER processor, and providing real time, dynamic inputs into the processor and monitoring the outputs. The control law selected and coded for the VIPER processor was the yaw damper function of an automatic landing program for a 737 aircraft. The mechanisms for interfacing the VIPER Single Board Computer to the VAX host are described. Results include run time experiences, performance evaluation, and comparison of VIPER and FORTRAN yaw damper algorithm output for accuracy estimation.

  11. A case study for the real-time experimental evaluation of the VIPER microprocessor

    NASA Astrophysics Data System (ADS)

    Carreno, Victor A.; Angellatta, Rob K.

    1991-09-01

    An experiment to evaluate the applicability of the Verifiable Integrated Processor for Enhanced Reliability (VIPER) microprocessor to real time control is described. The VIPER microprocessor was invented by the Royal Signals and Radar Establishment (RSRE), U.K., and is an example of the use of formal mathematical methods for developing electronic digital systems with a high degree of assurance on the system design and implementation correctness. The experiment consisted of selecting a control law, writing the control law algorithm for the VIPER processor, and providing real time, dynamic inputs into the processor and monitoring the outputs. The control law selected and coded for the VIPER processor was the yaw damper function of an automatic landing program for a 737 aircraft. The mechanisms for interfacing the VIPER Single Board Computer to the VAX host are described. Results include run time experiences, performance evaluation, and comparison of VIPER and FORTRAN yaw damper algorithm output for accuracy estimation.

  12. Envenoming by European vipers antivenom treatment--influence on morbidity.

    PubMed

    Persson, H

    2001-01-01

    The incidence of venomous viper bites in Europe is difficult to assess. Mortality after bites by European vipers is nowadays low, but morbidity is by no means negligible. Serious and life-threatening reactions occur, especially in small children and elderly people. The critically ill can nowadays be managed with symptomatic and supportive care in an astonishing way, but antivenom treatment may reduce the extent of such treatment and also reduced the overall risk for the patient. In particular, the only way to prevent extensive swelling and related complications is to give antivenom. The aim of this study was to test efficacy and safety of ovine Fab (a new specific ovine Fab fragments against various snake venoms) as an alternative to equine F(ab)2 antibodies in patients presenting with moderate and severe envenoming.

  13. Bionic research of pit vipers on infrared imaging.

    PubMed

    Zhang, Zhigang; Zhang, Yong; Zhang, Qingchuan; Cheng, Teng; Wu, Xiaoping

    2015-07-27

    The members of viperidae crotalinae (pit viper) family have special pit organs to detect infrared radiation in normal room conditions, whereas most artificial uncooled infrared focal plane arrays (FPAs) operate only in a vacuum chamber. Dissection shows that the pit membrane is a unique substrate-free structure. The temperature rise advantage of this pit organ was verified in comparison with an assumed substrate pit organ (as an artificial FPA structure). Inspired by the pit viper, we introduced this structure to infrared FPA, replacing the conventional substrate FPA. The substrate-free FPA was fabricated by micro-elctromechanical systems (MEMS) process and placed into an infrared imaging system to obtain thermal images of the human body in atmosphere and vacuum working conditions. We show that the infrared capability of the substrate-free pit organ was achieved.

  14. Measuring the VIPERS galaxy power spectrum at z∼1

    NASA Astrophysics Data System (ADS)

    Rota, Stefano; Bel, Julien; Granett, Ben; Guzzo, Luigi

    2016-10-01

    The VIMOS Public Extragalactic Redshift Survey [VIPERS, Guzzo et al. 2014] is using the VIMOS spectrograph at the ESO VLT to measure redshifts for ~ 100,000 galaxies with IAB < 22.5 and 0.5 < z < 1.2, over an area of 24 deg2 (split over the W1 and W4 fields of CFHTLS). VIPERS currently provides, at such redshifts, the best compromise between volume, number of galaxies and dense spatial sampling. We present here the first estimate of the power spectrum of the galaxy distribution, P(k), at redshifts z ~ 0.75 and z ~ 1, obtained from the ~ 55,000 redshifts of the PDR-1 data release. We discuss first constraints on cosmological quantities, as the matter density and the baryonic fraction, obtained for the first time at an epoch when the Universe was about half its current age.

  15. Bilateral Pulmonary Embolism Following a Viper Envenomation in France

    PubMed Central

    Bart, Géraldine; Pineau, Samuel; Biron, Charlotte; Connault, Jérôme; Artifoni, Mathieu

    2016-01-01

    Abstract Complications following snake bites are not common in France. We report the case of a bilateral pulmonary embolism following a viper envenomation in France. A healthy 72-year-old female presented with a lower limb hematoma following a viper bite. She was admitted at the hospital 2 days later and received low-molecular-weight heparin because of bed rest. Seven days later, she complained of thoracic pain and respiratory failure, and a bilateral pulmonary was diagnosed, without biological sign of neither disseminated intravascular coagulation nor coagulation trouble. Repeated lower limbs Doppler ultrasound were normal. This case is particularly interesting because it is only the 7th reported case of pulmonary embolism following a snake envenomation; moreover, it happened in France where poisonous snakes are very rare. Several hypotheses have been made to explain this late localized coagulopathy: an increased level of unstable fibrin produced by thrombin-like glycoproteins from the venom is one of them. PMID:27175626

  16. Formal verification of a microcoded VIPER microprocessor using HOL

    NASA Technical Reports Server (NTRS)

    Levitt, Karl; Arora, Tejkumar; Leung, Tony; Kalvala, Sara; Schubert, E. Thomas; Windley, Philip; Heckman, Mark; Cohen, Gerald C.

    1993-01-01

    The Royal Signals and Radar Establishment (RSRE) and members of the Hardware Verification Group at Cambridge University conducted a joint effort to prove the correspondence between the electronic block model and the top level specification of Viper. Unfortunately, the proof became too complex and unmanageable within the given time and funding constraints, and is thus incomplete as of the date of this report. This report describes an independent attempt to use the HOL (Cambridge Higher Order Logic) mechanical verifier to verify Viper. Deriving from recent results in hardware verification research at UC Davis, the approach has been to redesign the electronic block model to make it microcoded and to structure the proof in a series of decreasingly abstract interpreter levels, the lowest being the electronic block level. The highest level is the RSRE Viper instruction set. Owing to the new approach and some results on the proof of generic interpreters as applied to simple microprocessors, this attempt required an effort approximately an order of magnitude less than the previous one.

  17. Clustering-based redshift estimation: application to VIPERS/CFHTLS

    NASA Astrophysics Data System (ADS)

    Scottez, V.; Mellier, Y.; Granett, B. R.; Moutard, T.; Kilbinger, M.; Scodeggio, M.; Garilli, B.; Bolzonella, M.; de la Torre, S.; Guzzo, L.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Branchini, E.; Cappi, A.; Cucciati, O.; Davidzon, I.; Fritz, A.; Franzetti, P.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Bel, J.; Coupon, J.; De Lucia, G.; Ilbert, O.; McCracken, H. J.; Moscardini, L.

    2016-10-01

    We explore the accuracy of the clustering-based redshift estimation proposed by Ménard et al. when applied to VIMOS Public Extragalactic Redshift Survey (VIPERS) and Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) real data. This method enables us to reconstruct redshift distributions from measurement of the angular clustering of objects using a set of secure spectroscopic redshifts. We use state-of-the-art spectroscopic measurements with iAB < 22.5 from the VIPERS as reference population to infer the redshift distribution of galaxies from the CFHTLS T0007 release. VIPERS provides a nearly representative sample to a flux limit of iAB < 22.5 at a redshift of >0.5 which allows us to test the accuracy of the clustering-based redshift distributions. We show that this method enables us to reproduce the true mean colour-redshift relation when both populations have the same magnitude limit. We also show that this technique allows the inference of redshift distributions for a population fainter than the reference and we give an estimate of the colour-redshift mapping in this case. This last point is of great interest for future large-redshift surveys which require a complete faint spectroscopic sample.

  18. Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences.

    PubMed

    Lenk, P; Kalyabina, S; Wink, M; Joger, U

    2001-04-01

    Nucleotide sequences of mitochondrial cytochrome b and 16S rRNA genes, totaling 946 bp, were used to reconstruct a molecular phylogeny of 42 species of the subfamily Viperinae representing 12 of the 13 recognized genera. Maximum-parsimony and maximum-likelihood were used as methods for phylogeny reconstruction with and without a posteriori weighting. When representatives of the Causinae were taken as outgroup, five major monophyletic groups were consistently identified: Bitis, Cerastes, Echis, the Atherini (Atheris s.l.), and the Eurasian viperines. Proatheris was affiliated with Atheris, and Adenorhinos clustered within Atheris. The African Bitis consisted of at least three monophyletic groups: (i) the B. gabonica group, (ii) the B. caudalis group, and (iii) the B. cornuta group. B. worthingtoni and B. arietans are not included in any of these lineages. Eurasian viperines could be unambiguously devided into four monophyletic groups: (i) Pseudocerastes and Eristicophis, (ii) European vipers (Vipera s.str.), (iii) Middle East Macrovipera plus Montivipera (Vipera xanthina group), and (iv) North African Macrovipera plus Vipera palaestinae and Daboia russelii. These evolutionary lineages are consistent with historical biogeographical patterns. According to our analyses, the viperines originated in the Oligocene in Africa and successively underwent a first radiation leading to the five basal groups. The radiation might have been driven by the possession of an effective venom apparatus and a foraging startegy (sit-wait-strike) superior in most African biomes and might have been adaptive. The next diversifications led to the Proatheris-Atheris furcation, the basal Bitis splitting, and the emergence of the basal lineages within the Eurasian stock. Thereafter, lineages within Echis, Atheris, and Cerastes evolved. The emergence of three groups within Vipera s.l. might have been forced by the existence of three land masses during the early Miocene in the area of the

  19. Alleviation of viper venom induced platelet apoptosis by crocin (Crocus sativus): implications for thrombocytopenia in viper bites.

    PubMed

    Santhosh, M Sebastin; Thushara, R M; Hemshekhar, M; Sunitha, K; Devaraja, S; Kemparaju, K; Girish, K S

    2013-11-01

    Viper envenomations are characterized by prominent local and systemic manifestations including hematological alterations. Snake venom metalloproteinases (SVMPs) and phospholipase A2 (PLA2) plays crucial role in the pathophysiology of hemorrhage by targeting/altering the platelets function which may result in thrombocytopenia. Platelets undergo the classic events of mitochondria-mediated apoptotic pathway due to augmented endogenous reactive oxygen species (ROS) levels. The observed anticoagulant effects during viper envenomations could be due to exacerbated platelet apoptosis and thrombocytopenia. Moreover, antivenin treatments are ineffective against the venom-induced oxidative stress; therefore, it necessitates an auxiliary therapy involving antioxidants which can effectively scavenge the endothelium-generated/endogenous ROS and protect the platelets. The present study explored the effects of viper venom on platelet apoptosis and its amelioration by a phytochemical crocin. The study evaluated the Vipera russelli venom-induced apoptotic events including endogenous ROS generation, intracellular Ca(2+) mobilization, mitochondrial membrane depolarization, cyt-c translocation, caspase activation and phosphatidylserine externalization which were effectively mitigated when the venom was pre-treated with crocin. The study highlights one of the less studied features of venom-induced secondary complications i.e. platelet apoptosis and sheds light on the underlying basis for venom-induced thrombocytopenia, systemic hemorrhage and in vivo anticoagulant effect.

  20. The VIPER elements of trypanosomes constitute a novel group of tyrosine recombinase-enconding retrotransposons.

    PubMed

    Lorenzi, Hernan A; Robledo, German; Levin, Mariano J

    2006-02-01

    VIPER was initially characterized as a 2326bp LTR-like retroelement associated to SIRE, a short interspersed repetitive element specific of Trypanosoma cruzi. It carried a single ORF that coded for a putative reverse transcriptase-RNAse H protein, suggesting that it could be a truncated copy of a longer retroelement. Herein we report the identification and characterization of a complete 4480bp long VIPER in the T. cruzi genome. The complete VIPER harbored three non-overlapped domains encoding for a GAG-like, a tyrosine recombinase and a reverse transcriptase-RNAse H proteins. VIPER elements were also found in the genomes of Trypanosoma brucei and Trypanosoma vivax, but not in Leishmania sp. On the basis of its reverse transcriptase phylogeny, VIPER was classified as an LTR retroelement. However, VIPER was structurally related to the tyrosine recombinase encoding retroelements, DIRS and Ngaro. Phylogenetic analysis showed that VIPER's tyrosine recombinase grouped with the transposases RCI1 of Escherichia coli and Ye24 and Ye72 of Haemophilus influenzae within a major branch of prokaryotic recombinases. Taken together, VIPER's structure, the nature of its tyrosine recombinase, the unique features of its reverse transcriptase catalytic consensus motif and the fact that it was found in Trypanosomes, an early branching eukaryote, suggest that VIPER may be the closest relative of the founder element of the tyrosine recombinase encoding retrotransposons known up to date. Our analysis revealed that tyrosine recombinase-encoding retroelements were originated as early in evolution as non-LTR retroelements and suggests that VIPER, Ngaro and DIRS elements may constitute a third group of retrotransposons, distinct from both LTR and non-LTR retroelements.

  1. Infrared imaging in vipers: differential responses of crotaline and viperine snakes to paired thermal targets.

    PubMed

    Safer, Adam B; Grace, Michael S

    2004-09-23

    Pit vipers use infrared-sensitive pit organs to accurately target homeothermic prey even in the absence of visual cues. It has been suggested that other vipers, including large ambush predators of the genus Bitis, also may use radiant infrared information for predatory targeting. We compared behavioral responses of pit vipers and snakes of the viperine genus Bitis to paired targets of different temperatures (i.e. cool and warm balloons), some scented with rodent odors. The rates of tongue flicking, head turning and approaches by pit vipers (Agkistrodon contortrix and Crotalus atrox) were significantly higher toward warm targets than toward cool ones. Moreover, they all were significantly higher in pit vipers than in the vipers Bitis arietans, Bitis gabonica, and Bitis nasicornis. Bitis sp. exhibited no significant differences in their behaviors toward warm versus cool targets. Pit vipers often struck at targets (always the warm target even when paired with a prey-scented cool target), but Bitis sp. never struck at either warm or cool targets. These results show that the behavioral correlates of infrared-based predatory and/or defensive targeting differ significantly between these two groups of viperid snakes, and suggest that the neural substrates of infrared imaging in crotaline snakes are either absent or functionally distinct in viperine snakes of the genus Bitis.

  2. A high-dimensional look at VIPERS galaxies

    NASA Astrophysics Data System (ADS)

    Granett, Benjamin R.; Aff002

    2014-05-01

    We investigate how galaxies in VIPERS (the VIMOS Public Extragalactic Redshift Survey) inhabit the cosmological density field by examining the correlations across the observable parameter space of galaxy properties and clustering strength. The high-dimensional analysis is made manageable by the use of group-finding and regression tools. We find that the major trends in galaxy properties can be explained by a single parameter related to stellar mass. After subtracting this trend, residual correlations remain between galaxy properties and the local environment pointing to complex formation dependencies. As a specific application of this work we build subsamples of galaxies with specific clustering properties for use in cosmological tests.

  3. Viral association with the elusive rickettsia of viper plague from Ghana, West Africa.

    PubMed

    Kiel, Johnathan L; Gonzalez, Yvette; Parker, Jill E; Andrews, Carrie; Martinez, Dominique; Vachiéry, Nathalie; Lefrançois, Thierry

    2008-12-01

    We previously reported a rickettsial heartwater-like disease in vipers from Ghana that resembled heartwater in its gross lesions, was apparently transmitted by ticks (Aponomma and Amblyomma), and responded clinically favorably to early treatment with tetracycline. Cell culture showed consistent cytopathic effects in bovine endothelial cells, viper cells, and mouse cells, and inhibition of cytopathic effect by tetracycline in vitro. A type D retrovirus was observed in vacuoles in all infected cells. The virus and rickettsia infection was associated with transfer of cytopathic effect, regardless of cell species. Close association of virus and rickettsia may indicate a dual infection etiology of viper plague.

  4. VIPERS: in search for the solution of the riddle of dark energy (and many others)

    NASA Astrophysics Data System (ADS)

    Pollo, Agnieszka; Krywult, Janusz; Małek, Katarzyna; Solarz, Aleksandra; Vipers Team

    2014-12-01

    We present the "VIMOS Public Extragalactic Redshift Survey" (VIPERS). We discuss the present status of the survey, the data which are already open to the public, and review first scientific results of the project.

  5. A disease resembling inclusion body disease of boid snakes in captive palm vipers (Bothriechis marchi).

    PubMed

    Raymond, J T; Garner, M M; Nordhausen, R W; Jacobson, E R

    2001-01-01

    Between April 1998 and June 1999, 8 palm vipers (Bothriechis marchi) were diagnosed with a disease similar to inclusion body disease (IBD) of boids. Six palm vipers were captive bred, and 2 were wild caught. All of the vipers were adults at the time of death. Three palm vipers were found dead with no premonitory clinical signs, and 5 had anorexia plus possibly 1 of the following clinical signs: regurgitation, paresis, and dehydration. Histologically, all snakes had intracytoplasmic, round to oval, single to multiple eosinophilic inclusion bodies in hepatocytes and renal tubular epithelial cells. Inclusion bodies were distributed among other organs with varying frequency. Common concurrent histologic lesions were urate nephrosis, septic thrombi, and hepatocellular degeneration. Ultrastructurally, inclusions had features similar to inclusions in boid snakes with IBD.

  6. Report on the formal specification and partial verification of the VIPER microprocessor

    NASA Technical Reports Server (NTRS)

    Brock, Bishop; Hunt, Warren A., Jr.

    1991-01-01

    The VIPER microprocessor chip is partitioned into four levels of abstractions. At the highest level, VIPER is described with decreasingly abstract sets of functions in LCF-LSM. At the lowest level are the gate-level models in proprietary CAD languages. The block-level and gate-level specifications are also given in the ELLA simulation language. Among VIPER's deficiencies are the fact that there is no notion of external events in the top-level specification, and it is impossible to use the top-level specifications to prove abstract properties of programs running on VIPER computers. There is no complete proof that the gate-level specifications implement the top-level specifications. Cohn's proof that the major-state machine correctly implements the top-level specifications has no formal connection with any of the other proof attempts. None of the latter address resetting the machine, memory timeout, forced error, or single step modes.

  7. Myocarditis along with acute ischaemic cerebellar, pontine and lacunar infarction following viper bite.

    PubMed

    Bhatt, Alok; Menon, Aravind Ajakumar; Bhat, Rama; Ramamoorthi, Kusugodlu

    2013-09-06

    Cerebrovascular complications are rare following viper bites. A 65-year-old man presented with loss of consciousness and developed haemiparesis following a viper bite. Coagulation parameters were severely deranged. MRI showed acute ischaemic infarction on the left side in the precentral and postcentral gyrus, hemipons and cerebellum. Troponin T was elevated and transient left bundle branch block was seen. The patient had a good outcome following treatment with Anti Snake Venom and supportive therapy. Possible mechanisms of infarction are discussed.

  8. VizieR Online Data Catalog: VIPERS: galaxy colours and luminosity function (Fritz+, 2014)

    NASA Astrophysics Data System (ADS)

    Fritz, A.; Scodeggio, M.; Ilbert, O.; Bolzonella, M.; Davidzon, I.; Coupon, J.; Garilli, B.; Guzzo, L.; Zamorani, G.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Cucciati, O.; de Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Granett, B. R.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fevre, O.; Maccagni, D.; Malek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-11-01

    Completeness numbers, redshifts, colour intercept evolution, dispersion, Schechter parameters and number densities of the luminosity function are presented for ~45000 galaxies between 0.4VIPERS). In addition, redshifts, Schechter parameters and number densities of the luminosity function are presented for the sub-samples of Red and Red-SED galaxies. Completeness numbers are given for both the parent photometric sample and the spectroscopic VIPERS sample. (3 data files).

  9. Envenomation by a juvenile Malayan pit viper (Agkistrodon rhodostoma).

    PubMed

    Vest, D K; Kardong, K V

    1980-05-01

    Following an accidental bite inflicted by a juvenile Malayan pit viper (Agkistrodon rhodostoma), the progress of envenomation was carefully monitored and subsequent laboratory work performed to determine the amount and quality of venom injected. Even a very small amount of venom from this species is capable of inducing noticeable local symptoms including edema, subcutaneous bleeding, and throbbing. Constitutional symptoms were present but minimal. The extent of inflammation present at any given time following envenomation was found to be a more accurate diagnostic signal than the speed with which it developed. This case is similar to that of bites by juveniles of other species of viperines and crotalines and may serve to aid in the diagnosis and treatment of bites by juvenile specimens of serpents in these families.

  10. Improved correction of VIPERS angular selection effects in clustering measurements

    NASA Astrophysics Data System (ADS)

    Pezzotta, A.; Granett, B. R.; Bel, J.; Guzzo, L.; de la Torre, S.; Aff004

    2016-10-01

    Clustering estimates in galaxy redshift surveys need to account and correct for the way targets are selected from the general population, as to avoid biasing the measured values of cosmological parameters. The VIMOS Public Extragalactic Redshift Survey (VIPERS) is no exception to this, involving slit collisions and masking effects. Pushed by the increasing precision of the measurements, e.g. of the growth rate f, we have been re-assessing these effects in detail. We present here an improved correction for the two-point correlation function, capable to recover the amplitude of the monopole of the two-point correlation function ξ(r) above 1 h-1 Mpc to better than 2.

  11. Easylife: The Data Reduction and Survey Handling System for VIPERS

    NASA Astrophysics Data System (ADS)

    Garilli, B.; Paioro, L.; Scodeggio, M.; Franzetti, P.; Fumana, M.; Guzzo, L.

    2012-11-01

    We present Easylife, the software environment developed within the framework of the VIPERS project for automatic data reduction and survey handling. Easylife is a comprehensive system to automatically reduce spectroscopic data, to monitor the survey advancement at all stages, to distribute data within the collaboration, and to release data to the whole community. It is based on the OPTICON-founded project FASE, and inherits the FASE capabilities of modularity and scalability. After describing the software architecture, the main reduction and quality control features, and the main services made available, we show its performance in terms of reliability of results. We also show how it can be ported to other projects with different characteristics.

  12. Diversification in vipers: Phylogenetic relationships, time of divergence and shifts in speciation rates.

    PubMed

    Alencar, Laura R V; Quental, Tiago B; Grazziotin, Felipe G; Alfaro, Michael L; Martins, Marcio; Venzon, Mericien; Zaher, Hussam

    2016-12-01

    Snakes of the cosmopolitan family Viperidae comprise around 329 venomous species showing a striking heterogeneity in species richness among lineages. While the subfamily Azemiopinae comprises only two species, 70% of all viper species are arranged in the subfamily Crotalinae or the "pit vipers". The radiation of the pit vipers was marked by the evolution of the heat-sensing pits, which has been suggested to be a key innovation for the successful diversification of the group. Additionally, only crotalines were able to successfully colonize the New World. Here, we present the most complete molecular phylogeny for the family to date that comprises sequences from nuclear and mitochondrial genes representing 79% of all living vipers. We also investigated the time of divergence between lineages, using six fossils to calibrate the tree, and explored the hypothesis that crotalines have undergone an explosive radiation. Our phylogenetic analyses retrieved high support values for the monophyly of the family Viperidae, subfamilies Viperinae and Crotalinae, and 22 out of 27 genera, as well as well-supported intergeneric relationships throughout the family. We were able to recover a strongly supported sister clade to the New World pit vipers that comprises Gloydius, Ovophis, Protobothrops and Trimeresurus gracilis. Our results agree in many aspects with other studies focusing on the phylogenetics of vipers, but we recover new relationships as well. Despite the addition of new sequences we were not able to resolve some of the poor supported relationships previously suggested. Time of divergence estimates suggested that vipers started to radiate around the late Paleocene to middle Eocene with subfamilies most likely dating back to the Eocene. The invasion of the New World might have taken place sometime close to the Oligocene/Miocene boundary. Diversification analyses suggested a shift in speciation rates during the radiation of a sub-clade of pit vipers where speciation rates

  13. Functional and numerical responses of predators: where do vipers fit in the traditional paradigms?

    PubMed

    Nowak, Erika M; Theimer, Tad C; Schuett, Gordon W

    2008-11-01

    Snakes typically are not considered top carnivores, yet in many ecosystems they are a major predatory influence. A literature search confirmed that terrestrial ectotherms such as snakes are largely absent in most discussions of predator-prey dynamics. Here, we review classical functional and numerical responses of predator-prey relationships and then assess whether these traditional views are consistent with what we know of one group of snakes (true vipers and pitvipers: Viperidae). Specifically, we compare behavioural and physiological characteristics of vipers with those of more commonly studied mammalian (endothermic) predators and discuss how functional and numerical responses of vipers are fundamentally different. Overall, when compared to similar-sized endotherms, our analysis showed that vipers have: (i) lower functional responses owing primarily to longer prey handling times resulting from digestive limitations of consuming large prey and, for some adults, tolerance of fasting; (ii) stronger numerical responses resulting from higher efficiency of converting food into fitness currency (progeny), although this response often takes longer to be expressed; and (iii) reduced capacity for rapid numerical responses to short-term changes in prey abundance. Given these factors, the potential for viperids to regulate prey populations would most likely occur when prey populations are low. We provide suggestions for future research on key issues in predator-prey relationships of vipers, including their position within the classical paradigms of functional and numerical responses.

  14. Acute Myocardial Infarction following a possible direct intravenous bite of Russell’s viper (Daboia russelli)

    PubMed Central

    2012-01-01

    Background Russell’s viper (Daboia russelli) bites lead to high morbidity and mortality in South Asia. Although variety of clinical manifestations is reported in viper bite victims, myocardial ischemic events are rare. Case presentation We report a unique case of inferior wall ST elevation myocardial infarction due to a Russell’s viper bite over a vein with possible direct intravenous envenoming, in a young male with no past history or family history suggestive of ischemic cardiac disease, from Sri Lanka. In addition, the possible mechanisms of myocardial ischemia in snake bite victims are also briefly discussed. Conclusion Importance of the awareness of physicians on the rare, yet fatal manifestations of snake envenoming is highlighted. PMID:22971617

  15. Antiphospholipid syndrome: analysis of dilute Russell's viper venom time titer.

    PubMed

    Martinez, Alan P; Cunningham, Mark T

    2016-07-01

    To evaluate the characteristic features of the dilute Russell's viper venom time (DRVVT) titer in the antiphospholipid syndrome (APS). The medical record of 3660 consecutive patients with DRVVT orders between 2006 and 2015 were examined for criteria satisfying the diagnosis of APS. DRVVT titer was studied as a function of titer distribution, titer stability, and clinicopathologic features. Twenty-six patients were diagnosed with APS based on a persistently positive DRVVT and a history of arterial or venous thrombosis. DRVVT titer was mostly of low magnitude (65-77% of patients), was of similar value between initial and repeat testing (mean DRVVT titer 1.40 vs. 1.38; P = 0.858; mean time interval 216 days), and was positively associated with anticardiolipin antibodies (IgG and IgM) and antibeta-2-glycoprotein I antibodies (IgG and IgM) (P < 0.020). Low titer and moderate/high titer DRVVT were associated with a triple positive antiphospholipid antibody profile in 0 and 62% of patients, respectively (P < 0.020). DRVVT titer in APS was predominantly low in magnitude, stable over time, and associated with specific antiphospholipid antibody profiles.

  16. Galaxy Clusters and Properties in the CFHTLS/VIPERS Survey

    NASA Astrophysics Data System (ADS)

    Gallego Gallego, Sofia Carolina; Murphy, David; Hyazinth Puzia, Thomas

    2015-08-01

    We present our analysis of clusters in the CFHTLS Wide fields using a red-sequence based cluster finding code. The deep five-band photometry and panoramic coverage permits detection of galaxy clusters between z=0 and z~1 over 132 square degrees. We present a cluster catalogue and optical richness estimates as mass proxies, derived cluster properties from a novel template-fitting analysis and cluster redshift measurements utilizing data from the VLT/VIPERS spectroscopic survey.We complement our analysis with studies of mock cluster catalogues generated from N-body simulation lightcones featuring semi-analytic prescriptions of galaxy formation. These provide us with an insight into the performance of the cluster-finding technique, uncertainties in the derived properties of the detected cluster populations and an important comparison of the popular “lambda” optical richness estimator to known dark matter halo properties.This study serves as the perfect precursor to LSST-depth cluster science, providing an important input into how models describe the evolution of clusters and their members as a function of redshift and mass, and the role high-density environments play in galaxy evolution over half the Hubble time.

  17. Lessons Learned from Pit Viper Integration into Hanford Tank Farm Reality

    SciTech Connect

    Catalan, Michael A.; Bailey, Sharon A.; Alzheimer, James M.; Niebuhr, Daniel P.

    2002-05-11

    The Pit Viper is a tele-operated system intended to enhance worker safety while simultaneously improving the efficiency of pit operations at the Hanford Site. Commercial off-the-shelf (COTS) components were used in an attempt to increase system efficiency. During preparation for initial deployment, the Pit Viper team identified multiple areas where more advanced technology offers substantial improvement in system capabilities. The team also ensured that the system as is, was capable of fulfilling its mission. However, there are valid concerns of the reliability of the technology. Areas where improvement are desired include; operator feedback, manipulator dexterous envelope, and system reliability.

  18. VizieR Online Data Catalog: VIPERS Multi-Lambda Survey (Moutard+, 2016)

    NASA Astrophysics Data System (ADS)

    Moutard, T.; Arnouts, S.; Ilbert, O.; Coupon, J.; Hudelot, P.; Vibert, D.; Comte, V.; Conseil, S.; Davidzon, I.; Guzzo, L.; Llebaria, A.; Martin, C.; McCracken, H. J.; Milliard, B.; Morrison, G.; Schiminovich, D.; Treyer, M.; van Werbaeke, L.

    2016-05-01

    The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) is an imaging survey performed with Mega-Cam in five optical bands u*, g, r, i, z. we use the images and photometric catalogues of the W1 and W4 fields from the worldwide T00073 release produced by TERAPIX4. Since 2010, we have conducted a Ks-band follow-up of the VIPERS fields with the WIRCam instrument at CFHT. The original motivation was to guarantee an almost complete detection in Ks band of the VIPERS spectroscopic galaxies. (2 data files).

  19. A mitochondrial DNA phylogeny of the endangered vipers of the Vipera ursinii complex.

    PubMed

    Gvoždík, Václav; Jandzik, David; Cordos, Bogdan; Rehák, Ivan; Kotlík, Petr

    2012-03-01

    The last two populations of the Hungarian meadow viper Vipera ursinii rakosiensis were thought to persist in the steppe fragments of Hungary until meadow vipers were discovered in central Romania (Transylvania), suggesting a possible existence of remnant populations elsewhere. We assessed the phylogenetic position of the Transylvanian vipers using 2030 bp of mitochondrial DNA sequence. We showed that they were closely related to the Hungarian vipers, while those from northeastern Romania (Moldavia) and Danube Delta belonged to the subspecies Vipera ursinii moldavica. Montane subspecies from Europe (Vipera ursinii ursinii and Vipera ursinii macrops) formed a sister clade to the two lowland subspecies. Vipera renardi formed a sister clade to V. ursinii, with populations from the Greater Caucasus (Vipera renardi lotievi) and Tien Shan (Vipera renardi tienshanica) as the sister group to Vipera renardi renardi, and Vipera renardi eriwanensis from the Lesser Caucasus as the most basal taxon in the species. Our results illustrate that the divergence between the lowland and montane populations occurred separately in each species and several times in V. renardi. We demonstrated that the recently discovered Transylvanian population is the third surviving population of V. u. rakosiensis and the only known population outside of Hungary.

  20. Revisiting Russell's Viper (Daboia russelii) Bite in Sri Lanka: Is Abdominal Pain an Early Feature of Systemic Envenoming?

    PubMed Central

    Kularatne, Senanayake A. M.; Silva, Anjana; Weerakoon, Kosala; Maduwage, Kalana; Walathara, Chamara; Paranagama, Ranjith; Mendis, Suresh

    2014-01-01

    The Russell's viper (Daboia russelii) is responsible for 30–40% of all snakebites and the most number of life-threatening bites of any snake in Sri Lanka. The clinical profile of Russell's viper bite includes local swelling, coagulopathy, renal dysfunction and neuromuscular paralysis, based on which the syndromic diagnostic tools have been developed. The currently available Indian polyvalent antivenom is not very effective in treating Russell's viper bite patients in Sri Lanka and the decision regarding antivenom therapy is primarily driven by clinical and laboratory evidence of envenoming. The non-availability of early predictors of Russell's viper systemic envenoming is responsible for considerable delay in commencing antivenom. The objective of this study is to evaluate abdominal pain as an early feature of systemic envenoming following Russell's viper bites. We evaluated the clinical profile of Russell's viper bite patients admitted to a tertiary care centre in Sri Lanka. Fifty-five patients were proven Russell's viper bite victims who produced the biting snake, while one hundred and fifty-four were suspected to have been bitten by the same snake species. Coagulopathy (159, 76.1%), renal dysfunction (39, 18.7%), neuromuscular paralysis (146, 69.9%) and local envenoming (192, 91.9%) were seen in the victims, ranging from mono-systemic involvement to various combinations. Abdominal pain was present in 79.5% of these patients, appearing 5 minutes to 4 hours after the bite. The severity of the abdominal pain, assessed using a scoring system, correlated well with the severity of the coagulopathy (p<0.001) and the neurotoxicity (p<0.001). Its diagnostic validity to predict systemic envenoming is – Sensitivity 81.6%, Specificity 82.4%, Positive predictive value 91.2%. Thus, abdominal pain is an early clinical feature of systemic Russell's viper bite envenoming in Sri Lanka. However, it is best to judge abdominal pain together with other clinical manifestations on

  1. Emerging Tick-Borne Disease in African Vipers Caused by a Cowdria-like Organism

    DTIC Science & Technology

    2006-01-01

    Postmortem showed few gross lesions. The most consistent peracute and acute lesions were the pulmonary lesions and pericarditis with considerable...and pericarditis with considerable bloody fluid in the pericardial sac (hy- dropericardium). These lesions strongly resembled the lesions of heart...Department of Agriculture and Consumer Services passed an emergency rule restricting the importation into the State of all wildlife without an official Cer

  2. Microstructure-mediated Optical Effects in Southern African Snakes

    NASA Astrophysics Data System (ADS)

    Singh, Ishan; Alexander, Graham

    2017-03-01

    The scales of the African Viper Bitis arietans were tested for optical effects. Spectral intensity was recorded at incident angles over the visible spectrum for dark, pale, and ventral scale regions. The lowest spectral intensity recordings were associated with scales which have the greatest level of micro-structuring. Our results indicate that scale appearance in B. arietans is a product of microstructure-mediated optical effects. The optical effect may play a role in improving the ecological performance of the snake in its natural environment.

  3. The VIMOS Public Extragalactic Survey (VIPERS). First Data Release of 57 204 spectroscopic measurements

    NASA Astrophysics Data System (ADS)

    Garilli, B.; Guzzo, L.; Scodeggio, M.; Bolzonella, M.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fritz, A.; Fumana, M.; Granett, B. R.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zamorani, G.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-02-01

    We present the first Public Data Release (PDR-1) of the VIMOS Public Extragalactic Survey (VIPERS). It comprises 57 204 spectroscopic measurements together with all additional information necessary for optimal scientific exploitation of the data, in particular the associated photometric measurements and quantification of the photometric and survey completeness. VIPERS is an ESO Large Programme designed to build a spectroscopic sample of ≃100 000 galaxies with iAB < 22.5 and 0.5 < z < 1.2 with high sampling rate (≃45%). The survey spectroscopic targets are selected from the CFHTLS-Wide five-band catalogues in the W1 and W4 fields. The final survey will cover a total area of nearly 24 deg2, for a total comoving volume between z = 0.5 and 1.2 of ≃4 × 107 h-3 Mpc3 and a median galaxy redshift of z ≃ 0.8. The release presented in this paper includes data from virtually the entire W4 field and nearly half of the W1 area, thus representing 64% of the final dataset. We provide a detailed description of sample selection, observations and data reduction procedures; we summarise the global properties of the spectroscopic catalogue and explain the associated data products and their use, and provide all the details for accessing the data through the survey database (vipers.inaf.it">http://vipers.inaf.it) where all information can be queried interactively. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on

  4. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings.

    PubMed Central

    Wüster, Wolfgang; Allum, Christopher S. E.; Bjargardóttir, I. Birta; Bailey, Kimberley L.; Dawson, Karen J.; Guenioui, Jamel; Lewis, John; McGurk, Joe; Moore, Alix G.; Niskanen, Martti; Pollard, Christopher P.

    2004-01-01

    Predator avoidance of noxious prey, aposematism and defensive mimicry are normally associated with bright, contrasting patterns and colours. However, noxious prey may be unable to evolve conspicuous coloration because of other selective constraints, such as the need to be inconspicuous to their own prey or to specialist predators. Many venomous snakes, particularly most vipers, display patterns that are apparently cryptic, but nevertheless highly characteristic, and appear to be mimicked by other, non-venomous snakes. However, predator avoidance of viper patterns has never been demonstrated experimentally. Here, the analysis of 813 avian attacks on 12,636 Plasticine snake models in the field shows that models bearing the characteristic zigzag band of the adder (Vipera berus) are attacked significantly less frequently than plain models. This suggests that predator avoidance of inconspicuously but characteristically patterned noxious prey is possible. Our findings emphasize the importance of mimicry in the ecological and morphological diversification of advanced snakes. PMID:15590601

  5. Dilute Russell's viper venom and activated partial thromboplastin time in lupus anticoagulant diagnosis: is mixing essential?

    PubMed

    Chandrashekar, Vani

    2016-06-01

    Dilute Russell's viper venom (DRVV) testing and activated partial thromboplastin time (APTT) have been effectively used in combination for lupus anticoagulant testing. The purpose of our study was to evaluate the role of mixing in activated partial thromboplastin and dilute Russell's viper venom testing for evaluation of lupus anticoagulants. Citrated blood from patients who were not on oral anticoagulant therapy was studied. Mixing study with 1 : 1 normal plasma for elevated APTT and also few samples with elevated screen time was carried out. Elevated APTT was seen in only 48.1% of patients with lupus anticoagulant. Correction of APTT was seen in 27.8% of lupus anticoagulant-positive patients. DRVV test on mixing resulted in 83.8% false-negative values. Integrated DRVV test could be a standalone test for testing lupus anticoagulant. Mixing study may be restricted for patients on oral anticoagulants or patients with strong lupus anticoagulant.

  6. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings.

    PubMed

    Wüster, Wolfgang; Allum, Christopher S E; Bjargardóttir, I Birta; Bailey, Kimberley L; Dawson, Karen J; Guenioui, Jamel; Lewis, John; McGurk, Joe; Moore, Alix G; Niskanen, Martti; Pollard, Christopher P

    2004-12-07

    Predator avoidance of noxious prey, aposematism and defensive mimicry are normally associated with bright, contrasting patterns and colours. However, noxious prey may be unable to evolve conspicuous coloration because of other selective constraints, such as the need to be inconspicuous to their own prey or to specialist predators. Many venomous snakes, particularly most vipers, display patterns that are apparently cryptic, but nevertheless highly characteristic, and appear to be mimicked by other, non-venomous snakes. However, predator avoidance of viper patterns has never been demonstrated experimentally. Here, the analysis of 813 avian attacks on 12,636 Plasticine snake models in the field shows that models bearing the characteristic zigzag band of the adder (Vipera berus) are attacked significantly less frequently than plain models. This suggests that predator avoidance of inconspicuously but characteristically patterned noxious prey is possible. Our findings emphasize the importance of mimicry in the ecological and morphological diversification of advanced snakes.

  7. Molecular cloning of phospholipases A(2) from venom glands of Echis carpet vipers.

    PubMed

    Bharati, K; Hasson, S S; Oliver, J; Laing, G D; Theakston, R D G; Harrison, R A

    2003-06-01

    Venom toxin-specific antibodies offer a more rational treatment of snake envenoming than conventional antivenom. Here, we describe novel cDNAs encoding phospholipase A(2) (PLA(2)) isoforms from venom gland RNA of Echis pyramidum leakeyi (Epl), Echis sochureki (Es) and Echis ocellatus (Eo). The deduced amino acid sequences of these cDNAs encoded proteins with high overall sequence identity to the viper group II PLA(2) protein family, including the 14 cysteine residues capable of forming seven disulphide bonds that characterize this group of PLA(2) enzymes. Comparison of the PLA(2) sequences from Echis with those from related vipers failed to make significant geographic, taxonomic or PLA(2)-function distinctions between these Echis PLA(2) isoforms. However, their deduced hydrophilicity profiles revealed a conserved tertiary structure that we will exploit, by epidermal DNA immunization, to generate PLA(2)-neutralizing antibodies with polyspecific potential.

  8. Probing the accelerating Universe with redshift-space distortions in VIPERS

    NASA Astrophysics Data System (ADS)

    de la Torre, Sylvain

    2016-10-01

    We present the first measurement of the growth rate of structure at z=0.8. It has been obtained from the redshift-space distortions observed in the galaxy clustering pattern in the VIMOS Public Redshift survey (VIPERS) first data release. VIPERS is a large galaxy redshift survey probing the large-scale structure at 0.5 < z < 1.2 with an unprecedented accuracy. This measurement represents a new reference in the distant Universe, which has been poorly explored until now. We obtain σ8 = 0.47 +/- 0.08 at z = 0.8 that is consistent with the predictions of standard cosmological models based on Einstein gravity. This measurement alone is however not accurate enough to allow the detection of possible deviations from standard gravity.

  9. Pneumonia in Ottoman vipers (Vipera xanthena xanthena) associated with a parainfluenza 2-like virus.

    PubMed

    Potgieter, L N; Sigler, R E; Russell, R G

    1987-07-01

    A paramyxovirus related to parainfluenza 2 (PI2) virus was recovered from the lungs of two dead Ottoman vipers from a zoological collection. Snakes of other species in the collection were unaffected. Histologic examination of the vipers' lungs revealed interstitial pneumonia, and degeneration and hyperplasia of bronchial and atrial epithelia. Scattered vacuoles, some of which contain eosinophilic inclusion bodies, were seen in the cytoplasm of several cells of affected epithelial tissues. The virus recovered from pulmonary tissues of the snakes replicated optimally at 30 C in a variety of cell cultures and hemagglutinated chicken erythrocytes. Viral hemagglutination was inhibited by PI2 virus antiserum, but not by antisera to PI1, PI3, respiratory syncytial, and canine distemper viruses. Indirect immunofluorescence with PI2 antiserum specifically stained inclusions in the epithelial cells of respiratory tissues and infected cell cultures.

  10. Lethal herpesvirosis in 16 captive horned vipers (Vipera ammodytes ammodytes): pathological and ultrastructural findings.

    PubMed

    Catoi, C; Gal, A F; Taulescu, M A; Palmieri, C; Catoi, A F

    2014-01-01

    Sixteen captive adult horned vipers (Vipera ammodytes ammodytes) were submitted for necropsy examination following a 2-week history of lethargy, anorexia and dyspnoea. Gross lesions included widespread haemorrhage, serosanguineous effusions in the body cavities and multiple pinpoint white to yellow foci in the liver. Microscopically, there was multifocal hepatic coagulative necrosis associated with intranuclear acidophilic inclusion bodies in sinusoidal endothelial cells. Similar endothelial lesions were observed in the myocardium, fat bodies, kidneys and spleen. Transmission electron microscopy revealed numerous virions (100-110 nm) in the nuclei of endothelial cells and intracytoplasmic enveloped virions (140-150 nm) were also found. The gross and histological findings and the ultrastructural features of the intranuclear inclusions and viral particles were consistent with herpesviral infection. To the best of our knowledge, these are the first reported cases of a lethal herpesvirosis in horned vipers and the second report in snakes.

  11. Asp Viper (Vipera aspis) Envenomation: Experience of the Marseille Poison Centre from 1996 to 2008

    PubMed Central

    de Haro, Luc; Glaizal, Mathieu; Tichadou, Lucia; Blanc-Brisset, Ingrid; Hayek-Lanthois, Maryvonne

    2009-01-01

    A retrospective case review study of viper envenomations collected by the Marseille’s Poison Centre between 1996 and 2008 was performed. Results: 174 cases were studied (52 grade 1 = G1, 90 G2 and 32 G3). G1 patients received symptomatic treatments (average hospital stay 0.96 day). One hundred and six (106) of the G2/G3 patients were treated with the antivenom Viperfav* (2.1+/-0.9 days in hospital), while 15 of them received symptomatic treatments only (plus one immediate death) (8.1+/-4 days in hospital, 2 of them died). The hospital stay was significantly reduced in the antivenom treated group (p < 0.001), and none of the 106 antivenom treated patients had immediate (anaphylaxis) or delayed (serum sickness) allergic reactions. Conclusion: Viperfav* antivenom was safe and effective for treating asp viper venom-induced toxicity. PMID:22069534

  12. The VIMOS Public Extragalactic Redshift Survey (VIPERS): spectral classification through principal component analysis

    NASA Astrophysics Data System (ADS)

    Marchetti, A.; Granett, B. R.; Guzzo, L.; Fritz, A.; Garilli, B.; Scodeggio, M.; Abbas, U.; Adami, C.; Arnouts, S.; Bolzonella, M.; Bottini, D.; Cappi, A.; Coupon, J.; Cucciati, O.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fevre, O.; Maccagni, D.; Malek, K.; Marulli, F.; McCracken, H. J.; Meneux, B.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Bel, J.; Bersanelli, M.; Blaizot, J.; Branchini, E.; Burden, A.; Davidzon, I.; Di Porto, C.; Guennou, L.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Schimd, C.; Wolk, M.; Zamorani, G.

    2013-01-01

    We develop a Principal Component Analysis aimed at classifying a subset of 27 350 spectra of galaxies in the range 0.4 < z < 1.0 collected by the VIMOS Public Extragalactic Redshift Survey (VIPERS). We apply an iterative algorithm to simultaneously repair parts of spectra affected by noise and/or sky residuals, and reconstruct gaps due to rest-frame transformation, and obtain a set of orthogonal spectral templates that span the diversity of galaxy types. By taking the three most significant components, we find that we can describe the whole sample without contamination from noise. We produce a catalogue of eigencoefficients and template spectra that will be part of future VIPERS data releases. Our templates effectively condense the spectral information into two coefficients that can be related to the age and star formation rate of the galaxies. We examine the spectrophotometric types in this space and identify early, intermediate, late and starburst galaxies.

  13. Bilateral Pulmonary Embolism Following a Viper Envenomation in France: A Case Report and Review.

    PubMed

    Bart, Géraldine; Pineau, Samuel; Biron, Charlotte; Connault, Jérôme; Artifoni, Mathieu

    2016-05-01

    Complications following snake bites are not common in France. We report the case of a bilateral pulmonary embolism following a viper envenomation in France.A healthy 72-year-old female presented with a lower limb hematoma following a viper bite. She was admitted at the hospital 2 days later and received low-molecular-weight heparin because of bed rest. Seven days later, she complained of thoracic pain and respiratory failure, and a bilateral pulmonary was diagnosed, without biological sign of neither disseminated intravascular coagulation nor coagulation trouble. Repeated lower limbs Doppler ultrasound were normal.This case is particularly interesting because it is only the 7th reported case of pulmonary embolism following a snake envenomation; moreover, it happened in France where poisonous snakes are very rare.Several hypotheses have been made to explain this late localized coagulopathy: an increased level of unstable fibrin produced by thrombin-like glycoproteins from the venom is one of them.

  14. Resembling a viper: implications of mimicry for conservation of the endangered smooth snake.

    PubMed

    Valkonen, Janne K; Mappes, Johanna

    2014-12-01

    The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should

  15. Unusual venom phospholipases A2 of two primitive tree vipers Trimeresurus puniceus and Trimeresurus borneensis.

    PubMed

    Wang, Ying-Ming; Peng, Hao-Fan; Tsai, Inn-Ho

    2005-06-01

    To explore the venom diversity of Asian pit vipers, we investigated the structure and function of venom phospholipase A2 (PLA2) derived from two primitive tree vipers Trimeresurus puniceus and Trimeresurus borneensis. We purified six novel PLA2s from T. puniceus venom and another three from T. borneensis venom. All cDNAs encoding these PLA2s except one were cloned, and the molecular masses and N-terminal sequences of the purified enzymes closely matched those predicted from the cDNA. Three contain K49 and lack a disulfide bond at C61-C91, in contrast with the D49-containing PLA2s in both venom species. They are less thermally stable than other K49-PLA2s which contain seven disulfide bonds, as indicated by a decrease of 8.8 degrees C in the melting temperature measured by CD spectroscopy. The M110D mutation in one of the K49-PLA2s apparently reduced its edematous potency. A phylogenetic tree based on the amino-acid sequences of 17 K49-PLA2s from Asian pit viper venoms illustrates close relationships among the Trimeresurus species and intergeneric segregations. Basic D49-PLA2s with a unique Gly6 substitution were also purified from both venoms. They showed edema-inducing and anticoagulating activities. It is notable that acidic PLA2s from both venoms inhibited blood coagulation rather than platelet aggregation, and this inhibition was only partially dependent on enzyme activity. These results contribute to our understanding of the evolution of Trimeresurus pit vipers and the structure-function relationships between various subtypes of crotalid venom PLA2.

  16. VIPERS view of the star formation history of early-type galaxies

    NASA Astrophysics Data System (ADS)

    Siudek, M.; Malek, K.; Garilli, B.; Scodeggio, M.; Fritz, A.; Pollo, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Granett, B. R.; Guzzo, L.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.; Zamorani, G.

    2015-09-01

    We present studies over the relations between stellar mass, redshift and star formation history for a high quality sample of early-type galaxies (ETGs) observed by the by the VIMOS Public Extragalactic Redshift Survey (VIPERS). VIPERS is an ongoing Large Programme to map in detail the large-scale distribution of galaxies at 0:5 < z < 1:2 with a unique volume (24 deg2) and sampling rate (~= 45%). At this redshift, IPERS fills a unique niche in galaxy surveys, provides a exceptional opportunity to study galaxies and their evolution at an epoch when the Universe had approximately half its current age. VIPERS data set will become the z ~ 1 equivalent of current state-of-the-art local (z < 0:2) surveys, allowing us to compare measurements at these two different epochs on equal statistical footing. The final sample of this survey is going to reach nearly 100,000 galaxies. As the VIPERS sample contains ~ 15% of the early type galaxies with known spectroscopic redshift and a very good quality spectra, it is a perfect sample to study the star formation history based on their spectroscopic features. We show that there the age of stellar population is depending on the stellar mass and the redshift. Our results show that lower mass galaxies have young stellar populations, while higher mass ETGs are populated with old stars. This suggest that marginal star formation occurs in massive galaxies. This result is consistent with the observations of the local Universe. Moreover, this trend of evolution is preserved for the different redshift range between 0:4 < z < 1:2.

  17. Chronic Pituitary Failure Resembling Sheehan's Syndrome Following a Bite of Russell's Viper. A Case Report.

    PubMed

    Srinivasan, K G; Srividya, S; Usha Nandhini, K P; Ramprabananth, S

    2010-03-01

    Hypopituitarism can be the sequela of a variety of causes like postpartum pituitary necrosis or Sheehan's syndrome, lymphocytic hypophysitis, trauma and encephalitis. A very rare cause is envenomation by a bite of a Russell's viper. Very few cases with documented imaging findings of chronic pituitary failure resulting from snake bite have been reported. We describe a case of hypopituitarism with clinical, endocrine and magnetic resonance (MR) imaging studies occurring as a delayed complication of snake bite.

  18. Snake Venom Metalloproteinases and Their Peptide Inhibitors from Myanmar Russell’s Viper Venom

    PubMed Central

    Yee, Khin Than; Pitts, Morgan; Tongyoo, Pumipat; Rojnuckarin, Ponlapat; Wilkinson, Mark C.

    2016-01-01

    Russell’s viper bites are potentially fatal from severe bleeding, renal failure and capillary leakage. Snake venom metalloproteinases (SVMPs) are attributed to these effects. In addition to specific antivenom therapy, endogenous inhibitors from snakes are of interest in studies of new treatment modalities for neutralization of the effect of toxins. Two major snake venom metalloproteinases (SVMPs): RVV-X and Daborhagin were purified from Myanmar Russell’s viper venom using a new purification strategy. Using the Next Generation Sequencing (NGS) approach to explore the Myanmar RV venom gland transcriptome, mRNAs of novel tripeptide SVMP inhibitors (SVMPIs) were discovered. Two novel endogenous tripeptides, pERW and pEKW were identified and isolated from the crude venom. Both purified SVMPs showed caseinolytic activity. Additionally, RVV-X displayed specific proteolytic activity towards gelatin and Daborhagin showed potent fibrinogenolytic activity. These activities were inhibited by metal chelators. Notably, the synthetic peptide inhibitors, pERW and pEKW, completely inhibit the gelatinolytic and fibrinogenolytic activities of respective SVMPs at 5 mM concentration. These complete inhibitory effects suggest that these tripeptides deserve further study for development of a therapeutic candidate for Russell’s viper envenomation. PMID:28042812

  19. Lessons Learned from Pit Viper Integration into Hanford Tank Farm Reality

    SciTech Connect

    Catalan, Michael A.; Bailey, Sharon A.; Alzheimer, James M.; Niebuhr, Daniel P.

    2002-05-11

    Application of the As Low As Reasonably Achievable (ALARA) principle to many tasks across the Department of Energy (DOE) complex logically leads to the realization that remotely operated equipment is highly desirable. The Pit Viper is a tele-operated system intended for pit operations at the Hanford Site. Commercial off-the-shelf (COTS) components were used in an attempt to reduce integration hurdles and increase reliability. One key factor is that only a limited number of available, off-the-shelf robotic manipulator systems are available and all of them have some characteristics that present interfacing challenges. The state-of-the-art in remote technology is not as mature as many might hope. This paper describes the issues (and proposed improvements) that surfaced during the development and first deployment of the Pit Viper System. Important areas are contamination control, operator interface and operator training, adaptation of tools, and workspace interfaces. The Pit Viper, as is, provides significant improvement over the current baseline approaches.

  20. Quantitation of venom antigens from European vipers in human serum or urine by ELISA.

    PubMed

    Audebert, F; Grosselet, O; Sabouraud, A; Bon, C

    1993-01-01

    We describe an enzyme-linked immunosorbent assay (ELISA) to quantitate venom antigens in human serum and urine, and thus to help evaluate the severity of envenomation due to viper bites. This assay, which is performed with commercially available polyclonal Fab'2s in a double-sandwich method, is rapid, simple, and specific for antigens of European vipers (Vipera aspis, Vipera berus, and Vipera ammodytes). No cross-reactivity was observed with other snake venoms or human serum proteins. It showed a good linear response over a wide range of concentrations of venom antigens (from 1 to 100 ng/mL). It was very sensitive, with detection limits of 7 and 2 ng/mL for Vipera aspis venom in serum and urine, respectively. This ELISA is also easily reproducible; the coefficients of variation determined at different concentrations of venom (50, 25, and 5 ng/mL) did not exceed 10% in serum and 14% in urine samples collected from different donors. This test was applied to determine the concentrations of venom in the serum of patients bitten by a viper in France and to follow its elimination as a function of time. The method is adaptable to other venoms by using other specific immunoglobulins.

  1. VizieR Online Data Catalog: VIMOS Public Extragalactic Survey (VIPERS) DR1 (Garilli+, 2014)

    NASA Astrophysics Data System (ADS)

    Garilli, B.; Guzzo, L.; Scodeggio, M.; Bolzonella, M.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; de Lucia, G.; de la Torre, S.; Franzetti, P.; Fritz, A.; Fumana, M.; Granett, B. R.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fevre, O.; Maccagni, D.; Malek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zamorani, G.; Zanichelli, A.; Burden, A.; di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-09-01

    We present the first Public Data Release (PDR-1) of the VIMOS Public Extragalactic Survey (VIPERS). It comprises 57204 spectroscopic measurements together with all additional information necessary for optimal scientific exploitation of the data, in particular the associated photometric measurements and quantification of the photometric and survey completeness. VIPERS is an ESO Large Programme designed to build a spectroscopic sample of =~100000 galaxies with iAB<22.5 and 0.5vipers.inaf.it) where all information can be queried interactively. (4 data files).

  2. Snake velvet black: Hierarchical micro- and nanostructure enhances dark colouration in Bitis rhinoceros

    PubMed Central

    Spinner, Marlene; Kovalev, Alexander; Gorb, Stanislav N.; Westhoff, Guido

    2013-01-01

    The West African Gaboon viper (Bitis rhinoceros) is a master of camouflage due to its colouration pattern. Its skin is geometrically patterned and features black spots that purport an exceptional spatial depth due to their velvety surface texture. Our study shades light on micromorphology, optical characteristics and principles behind such a velvet black appearance. We revealed a unique hierarchical pattern of leaf-like microstructures striated with nanoridges on the snake scales that coincides with the distribution of black colouration. Velvet black sites demonstrate four times lower reflectance and higher absorbance than other scales in the UV – near IR spectral range. The combination of surface structures impeding reflectance and absorbing dark pigments, deposited in the skin material, provides reflecting less than 11% of the light reflected by a polytetrafluoroethylene diffuse reflectance standard in any direction. A view-angle independent black structural colour in snakes is reported here for the first time. PMID:23677278

  3. Snake velvet black: Hierarchical micro- and nanostructure enhances dark colouration in Bitis rhinoceros

    NASA Astrophysics Data System (ADS)

    Spinner, Marlene; Kovalev, Alexander; Gorb, Stanislav N.; Westhoff, Guido

    2013-05-01

    The West African Gaboon viper (Bitis rhinoceros) is a master of camouflage due to its colouration pattern. Its skin is geometrically patterned and features black spots that purport an exceptional spatial depth due to their velvety surface texture. Our study shades light on micromorphology, optical characteristics and principles behind such a velvet black appearance. We revealed a unique hierarchical pattern of leaf-like microstructures striated with nanoridges on the snake scales that coincides with the distribution of black colouration. Velvet black sites demonstrate four times lower reflectance and higher absorbance than other scales in the UV - near IR spectral range. The combination of surface structures impeding reflectance and absorbing dark pigments, deposited in the skin material, provides reflecting less than 11% of the light reflected by a polytetrafluoroethylene diffuse reflectance standard in any direction. A view-angle independent black structural colour in snakes is reported here for the first time.

  4. Clinical and Pharmacological Investigation of Myotoxicity in Sri Lankan Russell’s Viper (Daboia russelii) Envenoming

    PubMed Central

    Johnston, Christopher; Kuruppu, Sanjaya; Kneisz, Daniela; Maduwage, Kalana; Kleifeld, Oded; Smith, A. Ian; Siribaddana, Sisira; Buckley, Nicholas A.; Hodgson, Wayne C.; Isbister, Geoffrey K.

    2016-01-01

    Background Sri Lankan Russell’s viper (Daboia russelii) envenoming is reported to cause myotoxicity and neurotoxicity, which are different to the effects of envenoming by most other populations of Russell’s vipers. This study aimed to investigate evidence of myotoxicity in Russell’s viper envenoming, response to antivenom and the toxins responsible for myotoxicity. Methodology and Findings Clinical features of myotoxicity were assessed in authenticated Russell’s viper bite patients admitted to a Sri Lankan teaching hospital. Toxins were isolated using high-performance liquid chromatography. In-vitro myotoxicity of the venom and toxins was investigated in chick biventer nerve-muscle preparations. Of 245 enrolled patients, 177 (72.2%) had local myalgia and 173 (70.6%) had local muscle tenderness. Generalized myalgia and muscle tenderness were present in 35 (14.2%) and 29 (11.8%) patients, respectively. Thirty-seven patients had high (>300 U/l) serum creatine kinase (CK) concentrations in samples 24h post-bite (median: 666 U/l; maximum: 1066 U/l). Peak venom and 24h CK concentrations were not associated (Spearman’s correlation; p = 0.48). The 24h CK concentrations differed in patients without myotoxicity (median 58 U/l), compared to those with local (137 U/l) and generalised signs/symptoms of myotoxicity (107 U/l; p = 0.049). Venom caused concentration-dependent inhibition of direct twitches in the chick biventer cervicis nerve-muscle preparation, without completely abolishing direct twitches after 3 h even at 80 μg/ml. Indian polyvalent antivenom did not prevent in-vitro myotoxicity at recommended concentrations. Two phospholipase A2 toxins with molecular weights of 13kDa, U1-viperitoxin-Dr1a (19.2% of venom) and U1-viperitoxin-Dr1b (22.7% of venom), concentration dependently inhibited direct twitches in the chick biventer cervicis nerve-muscle preparation. At 3 μM, U1-viperitoxin-Dr1a abolished twitches, while U1-viperitoxin-Dr1b caused 70% inhibition of

  5. Prey envenomation does not improve digestive performance in Taiwanese pit vipers (Trimeresurus gracilis and T. stejnegeri stejnegeri).

    PubMed

    Chu, Chia-Wei; Tsai, Tein-Shun; Tsai, Inn-Ho; Lin, Yao-Sung; Tu, Ming-Chung

    2009-04-01

    It has been a common belief that snake venom may help in the digestion of its prey, although direct examples and supporting evidence have not been sufficient. To address this, the present study examined whether preinjecting natural amounts of pit viper venom into experimental mice may accelerate their digestion by the snakes or gain energy benefit as compared to the control without the envenomation. Live adults of two Asian pit viper species Trimeresurus gracilis and T. stejnegeri stejnegeri, which inhabit the cold and warm environment respectively, were the subjects studied herein. A natural dose of 1.2 mg of each of the pit viper venom in phosphate-buffered saline (PBS) was injected into the mouse (about 10% of the snake mass) before it was being fed to the same species of vipers, while the pit vipers in control group were given mouse injected with sterile PBS. The snakes were kept at 14 degrees C or 24 degrees C, and parameters of gut passage time, costs of digestion, and/or digestive efficiency were measured. The results did not support the hypotheses that envenomation facilitates prey digestion. The venom in fact caused longer first defecation time and lower assimilation energy at 14 degrees C. Besides, the time to reach the oxygen consumption peak, and the first defecation time of T. s. stejnegeri were longer than that of T. gracilis.

  6. Acute pituitary insufficiency and hypokalaemia following envenoming by Russell's viper (Daboia russelii) in Sri Lanka: Exploring the pathophysiological mechanisms.

    PubMed

    Jeevagan, Vijayabala; Katulanda, Prasad; Gnanathasan, Christeine Ariaranee; Warrell, David A

    2013-03-01

    Russell's viper envenoming is associated with a high incidence of morbidity and mortality. Hypopituitarism following envenoming by Russell's vipers is a well recognized sequel in Burma and parts of India but has been reported only once in Sri Lanka. Hypokalaemia following envenoming by Russell's viper has not been described. Here we describe the association of acute pituitary insufficiency and hypokalaemia following Russell's viper envenoming in Sri Lanka and review the literature in order to understand its pathophysiological basis. A previously healthy 21-year-old man was envenomed by a Russell's viper and treated with antivenom. Ten hours after the bite, he developed persistent hypotension, which responded promptly to intravenous dexamethasone. His hormone profiles were consistent with hypocortisolism secondary to acute pituitary insufficiency. He also developed hypokalaemia. Analysis of urine and serum electrolytes suggested redistribution of potassium in to the cells rather than renal loss. Hypotension and hypoglycaemic coma are life-threatening manifestations of acute pituitary insufficiency. Therefore prompt steroid administration in these setting is life saving. Awareness of these complications among physicians would help to make prompt diagnosis and initiate immediate life saving treatment.

  7. Development of VIPER: a simulator for assessing vision performance of warfighters

    NASA Astrophysics Data System (ADS)

    Familoni, Jide; Thompson, Roger; Moyer, Steve; Mueller, Gregory; Williams, Tim; Nguyen, Hung-Quang; Espinola, Richard L.; Sia, Rose K.; Ryan, Denise S.; Rivers, Bruce A.

    2016-05-01

    Background: When evaluating vision, it is important to assess not just the ability to read letters on a vision chart, but also how well one sees in real life scenarios. As part of the Warfighter Refractive Eye Surgery Program (WRESP), visual outcomes are assessed before and after refractive surgery. A Warfighter's ability to read signs and detect and identify objects is crucial, not only when deployed in a military setting, but also in their civilian lives. Objective: VIPER, a VIsion PERformance simulator was envisioned as actual video-based simulated driving to test warfighters' functional vision under realistic conditions. Designed to use interactive video image controlled environments at daytime, dusk, night, and with thermal imaging vision, it simulates the experience of viewing and identifying road signs and other objects while driving. We hypothesize that VIPER will facilitate efficient and quantifiable assessment of changes in vision and measurement of functional military performance. Study Design: Video images were recorded on an isolated 1.1 mile stretch of road with separate target sets of six simulated road signs and six objects of military interest, separately. The video footage were integrated with customdesigned C++ based software that presented the simulated drive to an observer on a computer monitor at 10, 20 or 30 miles/hour. VIPER permits the observer to indicate when a target is seen and when it is identified. Distances at which the observer recognizes and identifies targets are automatically logged. Errors in recognition and identification are also recorded. This first report describes VIPER's development and a preliminary study to establish a baseline for its performance. In the study, nine soldiers viewed simulations at 10 miles/hour and 30 miles/hour, run in randomized order for each participant seated at 36 inches from the monitor. Relevance: Ultimately, patients are interested in how their vision will affect their ability to perform daily

  8. Venomics of New World pit vipers: Genus-wide comparisons of venom proteomes across Agkistrodon

    PubMed Central

    Lomonte, Bruno; Tsai, Wan-Chih; Ureña-Diaz, Juan Manuel; Sanz, Libia; Mora-Obando, Diana; Sánchez, Elda E.; Fry, Bryan G.; Gutiérrez, José María; Gibbs, H. Lisle; Sovic, Michael G.; Calvete, Juan J.

    2015-01-01

    We report a genus-wide comparison of venom proteome variation across New World pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venoms of Agkistrodon bilineatus subspecies showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes. Biological significance A deep understanding of the structural and functional profiles of venoms and of the principles governing the evolution of venomous systems is a goal of venomics. Isolated proteomics analyses have been conducted on venoms from many species of vipers and pit vipers. However, making sense of these large inventories of data requires the integration of this information across multiple species to identify evolutionary and ecological trends. Our genus-wide venomics study provides a comprehensive overview of the toxic arsenal across

  9. Identification of single copy nuclear DNA markers for North American pit vipers.

    PubMed

    Gibbs, H Lisle; Diaz, Jose

    2010-01-01

    We describe 18 single copy nuclear DNA loci (10 loci cloned from a Sistrurus catenatus catenatus genomic library and eight intron-based loci amplified using conserved primers) that detect sequence variation in species from all genera (Sistrurus, Agkistrodon and Crotalus) of North American pit viper snakes. These loci (mean size in bp ± SE: 433 ± 51) show large numbers of phylogenetically informative sites across species (mean + SE: 10.2 ± 1.5), but limited variation within subspecies suggesting that they will be most useful for multilocus species-level phylogenetic analyses in these snakes.

  10. Herpes labialis in patients with Russell's viper bite and acute kidney injury: a single center experience.

    PubMed

    Waikhom, Rajesh; Sapam, Ranjeeta; Patil, Krishna; Jadhav, Jaya Prada; Sircar, Dipankar; Roychowdhury, Arpita; Dasgupta, Sanjay; Pandey, Rajendra

    2011-06-01

    Snake bite is an important health hazard in tropical countries and is associated with significant morbidity and mortality. Herpes labialis is a common ailment caused by the Herpes simplex virus. There is no published data showing any association between the snake bite and development of Herpes labialis. Here, we present a series of patients who developed Herpes labialis after Russell's viper bite and had acute kidney injury. We attempted to find whether snake bite is an immunosuppressed state and whether it could have pre-disposed the patients to the development of these lesions.

  11. Psychosis in Secondary Empty Sella Syndrome following a Russell's Viper Bite

    PubMed Central

    Ratnakaran, Badr; Punnoose, Varghese P.; Das, Soumitra; Kartha, Arjun

    2016-01-01

    Hypopituitarism can present with psychiatric symptoms. We report a unique case of psychosis in clear consciousness in a case of hypopituitarism due to the secondary empty sella syndrome following a Russell's viper bite which was untreated and presented with psychotic symptoms for past 13 years following the snake bite. After the diagnosis of psychosis due to hypopituitarism was made, the patient was treated with levothyroxine and prednisolone supplements and his psychotic symptoms subsided without any psychotropic drugs. Vasculotoxic snake bites can cause hypopituitarism and can present with psychosis. Further research will be needed into the prevalence of this phenomenon. PMID:27335524

  12. Structural and pharmacological comparison of daboiatoxin from Daboia russelli siamensis with viperotoxin F and vipoxin from other vipers.

    PubMed

    Gopalan, Gayathri; Thwin, Maung-Maung; Gopalakrishnakone, Ponnampalam; Swaminathan, Kunchithapadam

    2007-06-01

    Russell's viper (Vipera russelli, also known as Daboia russelli) is one of the major causes of fatal snakebites. To date, five Daboia russelli subspecies have been recognized. Daboiatoxin (DbTx) is the main lethal phospholipase A(2) (PLA(2)) toxin in the venom of D. russelli siamensis (Myanmar viper) and has strong neurotoxic, myotoxic and cytotoxic activities. DbTx and its homologous neurotoxins viperotoxin F from D. russelli formosensis (Taiwan viper) and vipoxin from the Bulgarian sand viper V. ammodytes meridionalis consist of complexes between a nontoxic acidic PLA(2) protein and an enzymatically active basic PLA(2). DbTx and viperotoxin F are presynaptic toxins, while vipoxin is postsynaptic. The two chains of DbTx have been separated and their PLA(2) enzymatic activity has been measured using the secretory PLA(2) assay kit. The enzymatic activity of DbTx chain B is reduced by 30% of its original activity by chain A in a unimolar ratio, thus indicating that DbTx chain A acts as an inhibitor. The lethal activity of the two chains has also been studied in male albino mice and chain A is less lethal than chain B. The crystal structure of DbTx has also been determined and its structural details are compared with those of the two homologues. Furthermore, an attempt is made to correlate the sequence and structural determinants of these toxins with their enzymatic activities and their pharmacological effects.

  13. Toxicity of venoms from vipers of Pelias group to crickets Gryllus assimilis and its relation to snake entomophagy.

    PubMed

    Starkov, Vladislav G; Osipov, Alexey V; Utkin, Yuri N

    2007-06-01

    The existing data indicate that snake venom is most toxic towards the natural vertebrate preys. Several species of snake include arthropods in their food. However, there is no available data on the toxicity of venom from entomophagous snakes towards their prey. We have studied the toxicity of venom from vipers of Pelias group towards crickets Gryllus assimilis. The Pelias group includes several closely related viper species inhabiting mainly the South European part of Russia, and they differ in their feeding preferences. Snakes from the Vipera renardi, Vipera lotievi, Vipera kaznakovi, and Vipera orlovi species feed on wide range of animals including insects, whereas snakes from Vipera berus and Vipera nikolskii species do not include insects in their diet. We have found that the venom from vipers that include insects in their diet possesses greater toxicity towards crickets. The greatest toxicity was observed for the venom from V. lotievi, which displays a preference for insects in its diet. Therefore, based on our data, we suggest that the viper entomophagy is not a result of behavior plasticity, but is probably determined at a genetic level.

  14. Structural and Pharmacological Comparison of Daboiatoxin from Badoia russelli siamensis with Viperotoxing F and Vipoxin from Other Vipers

    SciTech Connect

    Gopolan,G.; Thwin, M.; Gopalakrishnakone, P.; Swaminathan, K.

    2007-01-01

    Russell's viper (Vipera russelli, also known as Daboia russelli) is one of the major causes of fatal snakebites. To date, five Daboia russelli subspecies have been recognized. Daboiatoxin (DbTx) is the main lethal phospholipase A{sub 2} (PLA{sub 2}) toxin in the venom of D. russelli siamensis (Myanmar viper) and has strong neurotoxic, myotoxic and cytotoxic activities. DbTx and its homologous neurotoxins viperotoxin F from D. russelli formosensis (Taiwan viper) and vipoxin from the Bulgarian sand viper V. ammodytes meridionalis consist of complexes between a nontoxic acidic PLA2 protein and an enzymatically active basic PLA2. DbTx and viperotoxin F are presynaptic toxins, while vipoxin is postsynaptic. The two chains of DbTx have been separated and their PLA2 enzymatic activity has been measured using the secretory PLA2 assay kit. The enzymatic activity of DbTx chain B is reduced by 30% of its original activity by chain A in a unimolar ratio, thus indicating that DbTx chain A acts as an inhibitor. The lethal activity of the two chains has also been studied in male albino mice and chain A is less lethal than chain B. The crystal structure of DbTx has also been determined and its structural details are compared with those of the two homologues. Furthermore, an attempt is made to correlate the sequence and structural determinants of these toxins with their enzymatic activities and their pharmacological effects.

  15. VizieR Online Data Catalog: VIPERS. Searching for cosmic voids (Micheletti+, 2014)

    NASA Astrophysics Data System (ADS)

    Micheletti, D.; Hawken, A.; Iovino, A. J.; Granett, B.; Bolzonella, M.; Cappi, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Coupon, J.; Cucciati, O.; Davidzon, I.; de Lucia, G.; de la Torre, S.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Guzzo, L.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fevre, O.; Maccagni, D.; Malek, K.; Marulli, F.; McCracken, H. J.; Polletta, M.; Pollo, A.; Schimd, C.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moutard, T.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Zamorani, G.

    2014-09-01

    File voidtable.dat lists the catalogue of maximal spheres detected in VIPERS samples, divided in groups corresponding to individual voids. The spheres have been associated with larger under-densities using the percolation method, thus we associate each sphere with a void index indicating larger empty regions. The identification number (ID) of each maximal sphere is composed of: the VIPERS field to which the maximal sphere belongs (W1 or W4); a void index indicating to which void the sphere belongs (VVVV); a sphere index SSSS indicating the size rank of the sphere relative to other maximal spheres within the same void. The complete ID has the form Wx.VVVV.SSSS. For each maximal sphere of our catalogue we provide: its ID; its comoving radius in Mpc (Ωm=0.27, ΩΛ=0.73 and H0=70km/s/Mpc); the right ascension, declination, and redshift of the sphere's centre; a p-value giving the detection significance with respect to a Poisson distribution. Voids are sorted in ascending redshift order, with the redshift associated with each void being that of its largest sphere. Spheres inside each void are sorted in decreasing radius order. (1 data file).

  16. Haemostasis disorders caused by envenomation by Cerastes cerastes and Macrovipera mauritanica vipers.

    PubMed

    Fahmi, Laila; Makran, Bouchra; Boussadda, Lotfi; Lkhider, Mustapha; Ghalim, Noreddine

    2016-06-15

    Viper venoms are a real source of proteolytic enzymes causing clotting, bleeding, edema, necrosis, hemorrhage, pain at the bite site and systemic changes. This study was conducted to evaluate the changes induced in hematological and haemostatic parameters in rabbits after 1, 3, 6 and 24 h post-venom of subcutaneously administration of a sublethal dose of Cerastes cerastes and Macrovipera mauritanica venoms. Our results indicated that most hematological and haemostatic parameters showed significant changes 3 and 6 h after envenomation. The hemoglobin, hematocrit, red blood cells, platelets and prothrombin time were reduced significantly 3 h after envenomation. A very significant increase in the levels of white blood cells, lymphocytes, monocytes, activated thromboplastin time and fibrinogen were recorded 6 h following envenomation. However, no significant difference was found for the mean corpuscular volume, corpuscular hemoglobin content and mean corpuscular hemoglobin concentration throughout the whole duration of the experiment. These results suggest that severe hematological and haemostatic changes may be initiated during the early stages of envenomation leading to local and systemic hemorrhages and coagulopathies which are the main cause of death in case of vipers envenomation.

  17. Snake venomics of the Armenian mountain vipers Macrovipera lebetina obtusa and Vipera raddei.

    PubMed

    Sanz, Libia; Ayvazyan, Naira; Calvete, Juan J

    2008-07-21

    Venoms from the Armenian mountain vipers Macrovipera lebetina obtusa and Vipera raddei were analyzed by RP-HPLC, N-terminal sequencing, MALDI-TOF mass fingerprinting and CID-MS/MS. The venom proteins of M.l. obtusa and V. raddei belong to 9 and 11 families, respectively. The two mountain viper venoms share bradykinin-potentiating/C-natriuretic peptides, and proteins from the dimeric distegrin, DC-fragment, CRISP, PLA(2), serine proteinase, C-type lectin-like, L-amino acid oxidase, and Zn(2+)-dependent metalloproteinase families, albeit each species exhibits distinct relative abundances. M.l. obtusa and V. raddei venoms contain unique components, e.g. the short disintegrin obtustatin in M.l. obtusa, and Kunitz-type serine proteinase inhibitor and VEGF-like molecules in V. raddei. The toxin formulation of M.l. obtusa and V. raddei venoms may be related to their adaptation to rocky mountain ecosystems. On the other hand, the possibility that the VEGF-like proteins from V. raddei underlie the reported potential therapeutic value of V. raddei venom for regenerating damaged peripheral nerves deserves further investigations. Using a similarity coefficient, we estimate that the similarity of venom proteins between M. l. obtusa and M. l. transmediterranea is less than 4%. Although this result would support the classification of M.l. obtusa and M.l. transmediterranea as different species, additional detailed genomic analyses are also required.

  18. Purification of hemorrhagic SVMPs from venoms of three vipers of Egypt.

    PubMed

    Wahby, A F; Abdel-Aty, Azza M; El-Kady, E M

    2012-02-01

    Three viper P-III hemorrhagic SVMPs: EpyHTI (60 kDa), EcoHTI (60 kDa) and CcHTI (58 kDa) of the most dangerous vipers Echis pyramidum, Echis coloratus and Cerastes cerastes, respectively were purified and characterized in a set of biochemical assays. The SVMPs were purified by applying a protocol of three successive chromatographic steps. The enzymatic activity of the purified SVMPs was stimulated by the divalent cations Ca2+, Mg2+ and inhibited by metalloproteinase inhibitors and (Zn2+, Mn2+, Ni2+, Co2+, Cu2+ and Hg2), whereas inhibitors of serine and cysteine proteinases had no effect. The digestion of the BM proteins by purified SVMPs was much different, indicating different cleavage specificity for each of the purified SVMPs. Based on their intense hemorrhagic activity and molecular masses, the purified enzymes were hypothesized to belong to the P-III class of SVMPs. The three SVMPs possess close biochemical properties, but are different with respect to cleavage site, (fibronectin and fibrinogen). Furthermore, the described purification procedure allows simple preparation of appreciable quantities of the three SVMPs for further studies.

  19. Reduced performance of prey targeting in pit vipers with contralaterally occluded infrared and visual senses.

    PubMed

    Chen, Qin; Deng, Huanhuan; Brauth, Steven E; Ding, Li; Tang, Yezhong

    2012-01-01

    Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers. Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons. A series of ocular and pit organ occlusion experiments using the short-tailed pit viper (Gloydius brevicaudus) were conducted to investigate the role of visual and IR information during prey targeting. Compared with unoccluded controls, snakes with either both eyes or pit organs occluded performed more poorly in hunting prey although such subjects still captured prey on 75% of trials. Subjects with one eye and one pit occluded on the same side of the face performed as well as those with bilateral occlusion although these subjects showed a significant targeting angle bias toward the unoccluded side. Performance was significantly poorer when only a single eye or pit was available. Interestingly, when one eye and one pit organ were occluded on opposite sides of the face, performance was poorest, the snakes striking prey on no more than half the trials. These results indicate that, visual and infrared information are both effective in prey targeting in this species, although interference between the two modalities occurs if visual and IR information is restricted to opposite sides of the brain.

  20. Evolutionary trajectories of snake genes and genomes revealed by comparative analyses of five-pacer viper

    PubMed Central

    Yin, Wei; Wang, Zong-ji; Li, Qi-ye; Lian, Jin-ming; Zhou, Yang; Lu, Bing-zheng; Jin, Li-jun; Qiu, Peng-xin; Zhang, Pei; Zhu, Wen-bo; Wen, Bo; Huang, Yi-jun; Lin, Zhi-long; Qiu, Bi-tao; Su, Xing-wen; Yang, Huan-ming; Zhang, Guo-jie; Yan, Guang-mei; Zhou, Qi

    2016-01-01

    Snakes have numerous features distinctive from other tetrapods and a rich history of genome evolution that is still obscure. Here, we report the high-quality genome of the five-pacer viper, Deinagkistrodon acutus, and comparative analyses with other representative snake and lizard genomes. We map the evolutionary trajectories of transposable elements (TEs), developmental genes and sex chromosomes onto the snake phylogeny. TEs exhibit dynamic lineage-specific expansion, and many viper TEs show brain-specific gene expression along with their nearby genes. We detect signatures of adaptive evolution in olfactory, venom and thermal-sensing genes and also functional degeneration of genes associated with vision and hearing. Lineage-specific relaxation of functional constraints on respective Hox and Tbx limb-patterning genes supports fossil evidence for a successive loss of forelimbs then hindlimbs during snake evolution. Finally, we infer that the ZW sex chromosome pair had undergone at least three recombination suppression events in the ancestor of advanced snakes. These results altogether forge a framework for our deep understanding into snakes' history of molecular evolution. PMID:27708285

  1. The VIMOS Public Extragalactic Redshift Survey (VIPERS). A support vector machine classification of galaxies, stars, and AGNs

    NASA Astrophysics Data System (ADS)

    Małek, K.; Solarz, A.; Pollo, A.; Fritz, A.; Garilli, B.; Scodeggio, M.; Iovino, A.; Granett, B. R.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Guzzo, L.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fevre, O.; Maccagni, D.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.; Zamorani, G.

    2013-09-01

    Aims: The aim of this work is to develop a comprehensive method for classifying sources in large sky surveys and to apply the techniques to the VIMOS Public Extragalactic Redshift Survey (VIPERS). Using the optical (u∗,g',r',i') and near-infrared (NIR) data (z', Ks), we develop a classifier, based on broad-band photometry, for identifying stars, active galactic nuclei (AGNs), and galaxies, thereby improving the purity of the VIPERS sample. Methods: Support vector machine (SVM) supervised learning algorithms allow the automatic classification of objects into two or more classes based on a multidimensional parameter space. In this work, we tailored the SVM to classifying stars, AGNs, and galaxies and applied this classification to the VIPERS data. We trained the SVM using spectroscopically confirmed sources from the VIPERS and VVDS surveys. Results: We tested two SVM classifiers and concluded that including NIR data can significantly improve the efficiency of the classifier. The self-check of the best optical + NIR classifier has shown 97% accuracy in the classification of galaxies, 97% for stars, and 95% for AGNs in the 5-dimensional colour space. In the test of VIPERS sources with 99% redshift confidence, the classifier gives an accuracy equal to 94% for galaxies, 93% for stars, and 82% for AGNs. The method was applied to sources with low-quality spectra to verify their classification, hence increasing the security of measurements for almost 4900 objects. Conclusions: We conclude that the SVM algorithm trained on a carefully selected sample of galaxies, AGNs, and stars outperforms simple colour-colour selection methods and can be regarded as a very efficient classification method particularly suitable for modern large surveys. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programme 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint

  2. The VIMOS Public Extragalactic Redshift Survey (VIPERS). PCA-based automatic cleaning and reconstruction of survey spectra

    NASA Astrophysics Data System (ADS)

    Marchetti, A.; Garilli, B.; Granett, B. R.; Guzzo, L.; Iovino, A.; Scodeggio, M.; Bolzonella, M.; de la Torre, S.; Abbas, U.; Adami, C.; Bottini, D.; Cappi, A.; Cucciati, O.; Davidzon, I.; Franzetti, P.; Fritz, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Arnouts, S.; Bel, J.; Branchini, E.; Coupon, J.; De Lucia, G.; Ilbert, O.; Moutard, T.; Moscardini, L.; Zamorani, G.

    2017-03-01

    Context. Identifying spurious reduction artefacts in galaxy spectra is a challenge for large surveys. Aims: We present an algorithm for identifying and repairing spurious residual features in sky-subtracted galaxy spectra by using data from the VIMOS Public Extragalactic Redshift Survey (VIPERS) as a test case. Methods: The algorithm uses principal component analysis (PCA) applied to the galaxy spectra in the observed frame to identify sky line residuals imprinted at characteristic wavelengths. We further model the galaxy spectra in the rest-frame using PCA to estimate the most probable continuum in the corrupted spectral regions, which are then repaired. Results: We apply the method to 90 000 spectra from the VIPERS survey and compare the results with a subset for which careful editing was performed by hand. We find that the automatic technique reproduces the time-consuming manual cleaning in a uniform and objective manner across a large data sample. The mask data products produced in this work are released together with the VIPERS second public data release (PDR-2). based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA at the Canada-France-Hawaii Telescope (CFHT), that is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, which is a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/.

  3. Bites by Russell's vipers (Daboia russelii siamensis) in Myanmar: effect of the snake's length and recent feeding on venom antigenaemia and severity of envenoming.

    PubMed

    Tun-Pe; Ba-Aye; Aye-Aye-Myint; Tin-Nu-Swe; Warrell, D A

    1991-01-01

    An improved enzyme immunoassay technique (EIA) was used in the diagnosis of 311 suspected Russell's viper bite cases in Myanmar [Burma], 181 of whom (58%) had systemic envenoming. Russell's viper venom was detected in the sera of 175 (56.3%), cobra or green pit viper venoms in 4 (1.3%), and no venom in the remaining 132 (42.4). Among 175 of these patients who failed to bring the dead snake, EIA achieved a specific diagnosis of Russell's viper envenoming in 101 (58%). The serum venom antigen concentration was higher in patients with systemic envenoming than in those with local or no envenoming and it increased with the development of coagulopathy. Stomach contents were examined in 101 Russell's vipers responsible for bites. The presence of prey, usually a rodent, in the snake's stomach, indicating that it had eaten recently, did not influence the severity of envenoming, the initial venom level, or the percentage circumference increase and the extent of local swelling in the bitten limb. One hundred and fifty-five Russell's vipers responsible for bites showed a bimodal distribution of total lengths. The smaller snakes had probably been born that year. Longer snakes were responsible for more severe envenoming, a shorter interval between the bite and the detection of incoagulable blood, and more extensive local swelling with a greater percentage circumference increase of the bitten limb; but their bites were not associated with higher initial venom antigenaemia or a greater risk of developing acute renal failure.

  4. Venom phospholipases of Russell's vipers from Myanmar and eastern India--cloning, characterization and phylogeographic analysis.

    PubMed

    Tsai, Inn-Ho; Tsai, Hsin-Yu; Wang, Ying-Ming; Tun-Pe; Warrell, David A

    2007-08-01

    Venoms of Russell's vipers (genus Daboia) are known for their deadly coagulopathic and other effects. We herein studied various isoforms of venom phospholipases A(2) (PLAs) from two Daboia species at their geographic boundary. From Myanmar Daboia siamensis venom (designated as DsM), four PLAs (designated DsM-aI, aI', aII' and bI') were purified, and the cDNAs encoding two acidic (DsM-aI and aII) and two basic PLAs (DsM-bI and S1) were also cloned from its venom-glands. DsM-S1 is identical to the major venom PLA of southern India Daboia russelii, but the protein is absent from the venom. Additionally, four PLAs (designated DrK-aI, aII, bI and bII) were cloned from cDNA obtained from venom glands of a Kolkata D. russelii, and the PLAs were purified from the pooled venom (designated as DrK). The acidic DrK-aI is the most neurotoxic and lethal among these PLAs; DsM-aI which differs from DrK-aI by only the Phe2 substitution shows greatly reduced enzymatic activity and lethality. Both acidic PLAs do not form dimeric complex with basic PLAs in the same venoms. DsM-bI' is neurotoxic and lethal but its orthologous DrK-bI (97% identical to DsM-bI') is a much weaker toxin. Given the fact that most of the orthologous PLAs of DrK and DsM share 97-100% sequence identity, Daboia vipers of Myanmar and Kolkata must be closely related. Molecular phylogenetic analyses on 30 venom PLAs of Eurasian vipers' revealed co-evolution of five subtypes of venom PLAs in both Daboia and Vipera genera. Our results shed light on the intra- and inter-species variations and structure-function relationships of viperid venom PLAs.

  5. A phylogeny of the trimeresurus group of pit vipers: new evidence from a mitochondrial gene tree.

    PubMed

    Malhotra, A; Thorpe, R S

    2000-08-01

    The Trimeresurus group is an important radiation of over 40 Asian pit viper species. Once considered congeneric, four genera are generally currently recognized (Trimeresurus sensu stricto, Ovophis, Protobothrops, and Tropidolaemus) but relationships within and between these are still unclear. This study, based on mitochondrial cytochrome b sequences, is the first to include a large number of species (21) and demonstrates that the current taxonomy does not adequately represent either the relationships or the genetic diversity present in the complex. Although many deeper nodes are not strongly supported, the following novel conclusions are all well supported: (1) the paraphyly of Trimeresurus sensu stricto, (2) the presence of several divergent clades within Trimeresurus sensu stricto, (3) the paraphyly of some widespread, medically significant, species, (4) the nonmonophyly of Ovophis, and (5) the monophyly of Protobothrops. Mapping of morphological characters onto the mitochondrial tree further supports the four groups proposed for Trimeresurus sensu stricto.

  6. Comparative pathology of parasitic infections in free-ranging and captive pit vipers (Bothrops jararaca).

    PubMed

    Grego, K Fernandes; Gardiner, C H; Catão-Dias, J L

    2004-05-01

    Between June 1997 and May 1998, 47 pit vipers (Bothrops jararaca) (Group A) were euthanased when they were brought to the Instituto Butantan by farmers, and examined postmortem; during the same period, 91 snakes of the same species (group B) were examined after they had died in an outdoor serpentarium. The majority of the parasites encountered were nematodes; lungworms, Rhabdias vellardi, and the intestinal hookworm Kalicephalus inermis were the most common. Some of the snakes in group A were heavily infested, but their lesions were mild, whereas in group B the parasites were generally accompanied by severe lesions. The parasites with a direct life cycle were more common than those with obligatory intermediate hosts, and the snakes were more commonly infected during the hotter and more humid seasons.

  7. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Star formation history of passive red galaxies

    NASA Astrophysics Data System (ADS)

    Siudek, M.; Małek, K.; Scodeggio, M.; Garilli, B.; Pollo, A.; Haines, C. P.; Fritz, A.; Bolzonella, M.; de la Torre, S.; Granett, B. R.; Guzzo, L.; Abbas, U.; Adami, C.; Bottini, D.; Cappi, A.; Cucciati, O.; De Lucia, G.; Davidzon, I.; Franzetti, P.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Marchetti, A.; Marulli, F.; Polletta, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Arnouts, S.; Bel, J.; Branchini, E.; Ilbert, O.; Gargiulo, A.; Moscardini, L.; Takeuchi, T. T.; Zamorani, G.

    2017-01-01

    Aims: We trace the evolution and the star formation history of passive red galaxies, using a subset of the VIMOS Public Extragalactic Redshift Survey (VIPERS). The detailed spectral analysis of stellar populations of intermediate-redshift passive red galaxies allows the build up of their stellar content to be followed over the last 8 billion years. Methods: We extracted a sample of passive red galaxies in the redshift range 0.4 VIPERS survey. The sample was selected using an evolving cut in the rest-frame U-V color distribution and additional cuts that ensured high quality. The spectra of passive red galaxies were stacked in narrow bins of stellar mass and redshift. We use the stacked spectra to measure the 4000 Å break (D4000) and the Hδ Lick index (HδA) with high precision. These spectral features are used as indicators of the star formation history of passive red galaxies. We compare the results with a grid of synthetic spectra to constrain the star formation epochs of these galaxies. We characterize the formation redshift-stellar mass relation for intermediate-redshift passive red galaxies. Results: We find that at z 1 stellar populations in low-mass passive red galaxies are younger than in high-mass passive red galaxies, similar to what is observed at the present epoch. Over the full analyzed redshift range 0.4 < z < 1.0 and stellar mass range 10 < log (Mstar/M⊙) < 12, the D4000 index increases with redshift, while HδA gets lower. This implies that the stellar populations are getting older with increasing stellar mass. Comparison to the spectra of passive red galaxies in the SDSS survey (z 0.2) shows that the shape of the relations of D4000 and HδA with stellar mass has not changed significantly with redshift. Assuming a single burst formation, this implies that high-mass passive red galaxies formed their stars at zform 1.7, while low-mass galaxies formed their main stellar populations

  8. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Hierarchical scaling and biasing

    NASA Astrophysics Data System (ADS)

    Cappi, A.; Marulli, F.; Bel, J.; Cucciati, O.; Branchini, E.; de la Torre, S.; Moscardini, L.; Bolzonella, M.; Guzzo, L.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Granett, B. R.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Schimd, C.; Schlagenhaufer, H.; Wolk, M.; Zamorani, G.

    2015-07-01

    Aims: Building on the two-point correlation function analyses of the VIMOS Public Extragalactic Redshift Survey (VIPERS), we investigate the higher-order correlation properties of the same galaxy samples to test the hierarchical scaling hypothesis at z ~ 1 and the dependence on galaxy luminosity, stellar mass, and redshift. With this work we also aim to assess possible deviations from the linearity of galaxy bias independently from a previously performed analysis of our survey. Methods: We have measured the count probability distribution function in spherical cells of varying radii (3 ≤ R ≤ 10 h-1 Mpc), deriving σ8g (the galaxy rms at 8 h-1 Mpc), the volume-averaged two-, three-, and four-point correlation functions and the normalized skewness S3g and kurtosis S4g for different volume-limited subsamples, covering the following ranges: -19.5 ≤ MB(z = 1.1) - 5log (h) ≤ -21.0 in absolute magnitude, 9.0 ≤ log (M∗/M⊙h-2) ≤ 11.0 in stellar mass, and 0.5 ≤ z< 1.1 in redshift. Results: We have performed the first measurement of high-order correlation functions at z ~ 1 in a spectroscopic redshift survey. Our main results are the following. 1) The hierarchical scaling between the volume-averaged two- and three-point and two- and four-point correlation functions holds throughout the whole range of scale and redshift we could test. 2) We do not find a significant dependence of S3g on luminosity (below z = 0.9 the value of S3g decreases with luminosity, but only at 1σ-level). 3) We do not detect a significant dependence of S3g and S4g on scale, except beyond z ~ 0.9, where S3g and S4g have higher values on large scales (R ≥ 10 h-1 Mpc): this increase is mainly due to one of the two CFHTLS Wide Fields observed by VIPERS and can be explained as a consequence of sample variance, consistently with our analysis of mock catalogs. 4) We do not detect a significant evolution of S3g and S4g with redshift (apart from the increase of their values with scale in the

  9. VIPERS: An Unprecedented View of Galaxies and Large-scale Structure Halfway Back in the Life of the Universe

    NASA Astrophysics Data System (ADS)

    Guzzo, L.; The Vipers Team

    2013-03-01

    The VIMOS Public Extragalactic Redshift Survey (VIPERS) is an ongoing Large Programme to map in detail the large-scale distribution of galaxies at 0.5 < z <1.2. With a combination of volume and sampling density that is unique for these redshifts, it focuses on measuring galaxy clustering and related cosmological quantities as part of the grand challenge of understanding the origin of cosmic acceleration. Moreover, VIPERS has been designed to guarantee a broader legacy, allowing detailed investigations of the properties and evolutionary trends of z ~ 1 galaxies. The survey strategy exploits the specific advantages of VIMOS, aiming at a final sample of nearly 100 000 galaxy redshifts to iAB = 22.5 mag, which represents the largest redshift survey ever performed with ESO telescopes. In this article we describe the survey construction, together with early results based on a first sample of 55000 galaxies.

  10. Detection and Differentiation of Herpes Simplex Viruses by Use of the Viper Platform: Advantages, Limitations, and Concerns

    PubMed Central

    Lang, Amanda L. S.; Roberts, Catherine; Mazzulli, Tony; Hatchette, Todd F.

    2014-01-01

    The Viper HSV-Qx assay was evaluated for the detection of herpes simplex virus 1 (HSV-1) and HSV-2 in specimens from oral, anogenital, and other miscellaneous sites. The HSV-Qx assay was found to be highly sensitive and accurate; however, a gray zone may be required for specimens with values falling between 50 and 800 maximum relative fluorescence units. PMID:24696023

  11. Detection and differentiation of herpes simplex viruses by use of the viper platform: advantages, limitations, and concerns.

    PubMed

    Lang, Amanda L S; Roberts, Catherine; Mazzulli, Tony; Hatchette, Todd F; LeBlanc, Jason J

    2014-06-01

    The Viper HSV-Q(x) assay was evaluated for the detection of herpes simplex virus 1 (HSV-1) and HSV-2 in specimens from oral, anogenital, and other miscellaneous sites. The HSV-Q(x) assay was found to be highly sensitive and accurate; however, a gray zone may be required for specimens with values falling between 50 and 800 maximum relative fluorescence units.

  12. The VIMOS Public Extragalactic Redshift Survey (VIPERS). On the recovery of the count-in-cell probability distribution function

    NASA Astrophysics Data System (ADS)

    Bel, J.; Branchini, E.; Di Porto, C.; Cucciati, O.; Granett, B. R.; Iovino, A.; de la Torre, S.; Marinoni, C.; Guzzo, L.; Moscardini, L.; Cappi, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bolzonella, M.; Bottini, D.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Marchetti, A.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2016-04-01

    We compare three methods to measure the count-in-cell probability density function of galaxies in a spectroscopic redshift survey. From this comparison we found that, when the sampling is low (the average number of object per cell is around unity), it is necessary to use a parametric method to model the galaxy distribution. We used a set of mock catalogues of VIPERS to verify if we were able to reconstruct the cell-count probability distribution once the observational strategy is applied. We find that, in the simulated catalogues, the probability distribution of galaxies is better represented by a Gamma expansion than a skewed log-normal distribution. Finally, we correct the cell-count probability distribution function from the angular selection effect of the VIMOS instrument and study the redshift and absolute magnitude dependency of the underlying galaxy density function in VIPERS from redshift 0.5 to 1.1. We found a very weak evolution of the probability density distribution function and that it is well approximated by a Gamma distribution, independently of the chosen tracers. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programmes 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/

  13. Immunological cross-reactivity and neutralisation of European viper venoms with the monospecific Vipera berus antivenom ViperaTAb.

    PubMed

    Casewell, Nicholas R; Al-Abdulla, Ibrahim; Smith, David; Coxon, Ruth; Landon, John

    2014-08-19

    Medically important cases of snakebite in Europe are predominately caused by European vipers of the genus Vipera. The mainstay of snakebite therapy is polyclonal antibody therapy, referred to as antivenom. Here we investigate the capability of the monospecific V. berus antivenom, ViperaTAb®, to cross-react with, and neutralise lethality induced by, a variety of European vipers. Using ELISA and immunoblotting, we find that ViperaTAb® antibodies recognise and bind to the majority of toxic components found in the venoms of the Vipera species tested at comparably high levels to those observed with V. berus. Using in vivo pre-clinical efficacy studies, we demonstrate that ViperaTAb® effectively neutralises lethality induced by V. berus, V. aspis, V. ammodytes and V. latastei venoms and at much higher levels than those outlined by regulatory pharmacopoeial guidelines. Notably, venom neutralisation was found to be superior to (V. berus, V. aspis and V. latastei), or as equally effective as (V. ammodytes), the monospecific V. ammodytes "Zagreb antivenom", which has long been successfully used for treating European snake envenomings. This study suggests that ViperaTAb® may be a valuable therapeutic product for treating snakebite by a variety of European vipers found throughout the continent.

  14. Impact of cool versus warm temperatures on gestation in the aspic viper (Vipera aspis).

    PubMed

    Michel, Catherine Louise; Pastore, Jean-Henri; Bonnet, Xavier

    2013-07-01

    Previous experimental data suggested that digestion and growth rates are not impaired under cool constant temperature (23°C) in a viviparous snake (Vipera aspis). These results challenged the widespread notion that both elevated temperatures (e.g. 30°C) and temperature fluctuations are required for digestion and growth in temperate climate reptiles. Here, we investigated the impact of constant cool temperatures on another physiological performance that is crucial to population persistence: gestation. At the time when reproductive females were midway through vitellogenesis, we placed ten reproductive and two non-reproductive female aspic vipers at each of two contrasted constant temperature conditions: cool (23°C) versus warm (28°C). Sixty percent of the females placed at 28°C gave birth to healthy offspring, suggesting that constant warm body temperatures were compatible with normal offspring production. Conversely, none of the cool females gave birth to healthy offspring. A blister disease affected exclusively cool pregnant females. Apparently, the combination of cool temperatures plus gestation was too challenging for such females. Our results suggest that reproduction is more thermally sensitive than digestion or growth, indeed gestation faltered under moderately cool thermal constraints. This sensitivity could be a crucial factor determining the capacity of this species to colonize different habitats.

  15. The life and viper of Dr Patrick Russell MD FRS (1727-1805): physician and naturalist.

    PubMed

    Hawgood, B J

    1994-11-01

    It is nearly two hundred years since the publication in 1796 of An Account of Indian Serpents collected on the Coast of Coromandel by Patrick Russell. Within the folio is a drawing and description of the venomous snake called Katuka Rekula Poda in the local Telugu language, whose venom was shown experimentally by Dr Russell to be nearly as lethal as that of Cobra de Capello. The snake is now known as Vipera russelli or Russell's viper. Dr Russell was representative of the naturalistic tendency of British medicine in the late 18th century. He was a keen observer and skilled doctor in clinical practice, particularly in Aleppo, Syria, during an outbreak of the plague, and indefatigable in his study of plant and animal life both in Aleppo and later in the Madras Province of India. As a physician as well as Naturalist to the East India Company in the Carnatic he was concerned with the problem of snakebite. His first aim was to find a means whereby the non-specialist could distinguish between poisonous and harmless snakes and so combat the terrible notion that all bites were mortal. His writing, encompassing social and natural histories and climaxed by a study of snakes, has left a rich legacy. Dr Patrick Russell was a man of the highest integrity and ability, a physician and naturalist par excellence.

  16. Clinical usefulness of the dilute Russell viper venom time test for patients taking warfarin.

    PubMed

    Kanouchi, Kazunori; Narimatsu, Hiroto; Ohnuma, Okio; Morikane, Keita; Fukao, Akira

    2017-04-07

    Warfarin use often causes false-positive results in the dilute Russell viper venom time test (DRVVT). Thus, three sets of guidelines-those presented by the International Society on Haemostasis and Thrombosis (ISTH), the British Committee for Standards in Haematology (BCSH), and the Clinical and Laboratory Standards Institute (CLSI)-are advocated. We evaluated the clinical usefulness of the testing methods recommended in these three guidelines using laboratory samples. Of the 242 samples from patients using warfarin, 38 were positive for lupus anticoagulant (LA). After adding normal pooled plasma (NPP) as recommended in the ISTH, BCSH, and CLSI guidelines, the number of samples testing positive for LA decreased to 13, 18, and 19, respectively. The number of samples with inconsistent results between the activated partial thromboplastin time and mixing test, and the DRVVT following the ISTH, BCSH, and CLSI guidelines were four of 205 (1.9%), 15 of 242 (6.2%), and 17 of 242 (7.0%), respectively. In patients with an international normalized ratio (INR) ≥3.0, 11 of 37 (29.7%) and 12 of 37 (32.4%) samples showed inconsistent results according to the BCSH and CLSI guidelines, respectively. The accuracy of the DRVVT result may thus decrease in markedly anticoagulated patients.

  17. Viper cabin-fuselage structural design concept with engine installation and wing structural design

    NASA Technical Reports Server (NTRS)

    Marchesseault, B.; Carr, D.; Mccorkle, T.; Stevens, C.; Turner, D.

    1993-01-01

    This report describes the process and considerations in designing the cabin, nose, drive shaft, and wing assemblies for the 'Viper' concept aircraft. Interfaces of these assemblies, as well as interfaces with the sections of the aircraft aft of the cabin, are also discussed. The results of the design process are included. The goal of this project is to provide a structural design which complies with FAR 23 requirements regarding occupant safety, emergency landing loads, and maneuvering loads. The design must also address the interfaces of the various systems in the cabin, nose, and wing, including the drive shaft, venting, vacuum, electrical, fuel, and control systems. Interfaces between the cabin assembly and the wing carrythrough and empennage assemblies were required, as well. In the design of the wing assemblies, consistency with the existing cabin design was required. The major areas considered in this report are materials and construction, loading, maintenance, environmental considerations, wing assembly fatigue, and weight. The first three areas are developed separately for the nose, cabin, drive shaft, and wing assemblies, while the last three are discussed for the entire design. For each assembly, loading calculations were performed to determine the proper sizing of major load carrying components. Table 1.0 lists the resulting margins of safety for these key components, along with the types of the loads involved, and the page number upon which they are discussed.

  18. The use of ground-borne vibrations for prey localization in the Saharan sand vipers (Cerastes).

    PubMed

    Young, Bruce A; Morain, Malinda

    2002-03-01

    Sand vipers of the genus Cerastes are specialized semi-fossorial snakes that launch predatory strikes at rodents and lizards while partially buried in the soft sand of the Saharan desert. This study attempted to document which environmental stimuli are used by these snakes as a trigger for the ambush behavior. Denervating the olfactory and vomeronasal organs produced no changes in prey capture behavior in Cerastes cerastes. Occluding the eyes of the denervated specimens resulted in significant decreases in strike distance, diversity of strike angle and strike accuracy, demonstrating the importance of visual stimuli for target acquisition in this species. Nevertheless, every olfactory-denervated, temporarily blinded specimen succeeded in capturing free-ranging mice in every trial. Presentation of chemosensory-neutral targets to the olfactory-denervated, temporarily blinded specimens resulted in similar predatory behaviors, whether the target was isothermic to the environment or heated to mammalian body temperature. Collectively, these results provide evidence for the importance of visual stimuli during foraging in C. cerastes, the first experimental evidence for foraging by vibration detection in snakes and the strongest evidence to date that snakes are capable of 'hearing' vibrational stimuli.

  19. A nesting of vipers: Phylogeny and historical biogeography of the Viperidae (Squamata: Serpentes).

    PubMed

    Wüster, Wolfgang; Peppin, Lindsay; Pook, Catharine E; Walker, Daniel E

    2008-11-01

    Despite their medical interest, the phylogeny of the snake family Viperidae remains inadequately understood. Previous studies have generally focused either on the pitvipers (Crotalinae) or on the Old World vipers (Viperinae), but there has been no comprehensive molecular study of the Viperidae as a whole, leaving the affinities of key taxa unresolved. Here, we infer the phylogenetic relationships among the extant genera of the Viperidae from the sequences of four mitochondrial genes (cytochrome b, NADH subunit 4, 16S and 12S rRNA). The results confirm Azemiops as the sister group of the Crotalinae, whereas Causus is nested within the Viperinae, and thus not a basal viperid or viperine. Relationships among the major clades of Viperinae remain poorly resolved despite increased sequence information compared to previous studies. Bayesian molecular dating in conjunction with dispersal-vicariance analysis suggests an early Tertiary origin in Asia for the crown group Viperidae, and rejects suggestions of a relatively recent, early to mid-Tertiary origin of the Caenophidia.

  20. Comparative proteomics and subtyping of venom phospholipases A2 and disintegrins of Protobothrops pit vipers.

    PubMed

    Tsai, Inn-Ho; Chen, Yi-Hsuan; Wang, Ying-Ming

    2004-10-01

    To explore the venom diversity and systematics of pit vipers under the genus Protobothrops, the venom phospholipases A2 (PLA2s) of P. mangshanensis, P. elegans and P. tokarensis were purified and characterized for the first time. The results were compared with the corresponding venom data of other co-generic species including P. mucrosquamatus, P. flavoviridis and P. jerdonii. Based on sequence features at the N-terminal regions, we identified five PLA2 subtypes, i.e., the Asp49-PLA2s with N6, E6 or R6 substitution and the Lys49-PLA2. However, not all subtypes were expressed in each of the species. Venom N6-PLA2s from P. mangshanensis and P. tokarensis venom were weakly neurotoxic toward chick biventer cervicis tissue preparations. The venoms of P. tokarensis and P. flavoviridis contained identical PLA2 isoforms. In most Protobothrop disintegrins, sequences flanking the RGD-motif are conserved. Phylogenetic analyses based on amino acid sequences of both families of the acidic PLA2s and the disintegrins clarify that these species could belong to a monophyletic group.

  1. The in vitro toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Hypnale).

    PubMed

    Maduwage, Kalana; Hodgson, Wayne C; Konstantakopoulos, Nicki; O'Leary, Margaret A; Gawarammana, Indika; Isbister, Geoffrey K

    2011-01-01

    Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopathy and acute renal failure. Currently there are three nominal species of this genus: H. hypnale, H. zara and H. nepa. This study investigates the biochemical and pharmacological properties of the venoms from the three Hypnale species in Sri Lanka. The three Hypnale venoms had similar chromatographic profiles using reverse phase high performance liquid chromatography and fractions with procoagulant activity were identified. Hypnale venoms had potent cytotoxicity in cultured rat aorta smooth muscle cells with similar IC(50) values. The venoms had weak neurotoxic and myotoxic activity in the isolated chick biventer muscle preparation. They had mild procoagulant activity with close MCC(5) values and also phospholipase activity. Locally available polyvalent antivenom did not neutralise any venom effects. The study demonstrates that the three Hypnale venoms are similar and cytotoxicity appears to be the most potent effect, although they have mild procoagulant activity. These findings are consistent with clinical reports.

  2. A comparative study of the biological properties of venoms of some old world vipers (subfamily viperinae).

    PubMed

    Tan, N H; Ponnudurai, G

    1992-02-01

    1. The hemorrhagic, procoagulant, anticoagulant, phosphodiesterase, hyaluronidase, alkaline phosphomonoesterase, 5'-nucleotidase, arginine ester hydrolase, phospholipase A, L-amino acid oxidase and protease activities of 30 samples of venoms from nine species (12 taxa) of the old world vipers (Subfamily Viperinae) including snakes from the genera Bitis, Causus, Cerastes, Echis, Eristicophis and Pseudocerastes, were determined and the Sephadex G-75 gel filtration patterns for some of the venoms were also examined. 2. Examination of the biological properties of the venoms of the Viperinae tested indicates the presence of common venom biological characteristics at the various phylogenic levels. 3. Venoms of most species of the Viperinae examined exhibited characteristic biological properties at the species level, and this allows the differentiation of the Viperinae species by differences in their biological properties. 4. Particularly useful for this purpose, are the effects of venom on kaolin-cephalin clotting time of platelet poor rabbit plasma and the Sephadex G-75 gel filtration pattern and arginine ester hydrolase activity of the venom.

  3. Hybridization at an ecotone: ecological and genetic barriers between three Iberian vipers.

    PubMed

    Tarroso, Pedro; Pereira, Ricardo J; Martínez-Freiría, Fernando; Godinho, Raquel; Brito, José C

    2014-03-01

    The formation of stable genetic boundaries between emerging species is often diagnosed by reduced hybrid fitness relative to parental taxa. This reduced fitness can arise from endogenous and/or exogenous barriers to gene flow. Although detecting exogenous barriers in nature is difficult, we can estimate the role of ecological divergence in driving species boundaries by integrating molecular and ecological niche modelling tools. Here, we focus on a three-way secondary contact zone between three viper species (Vipera aspis, V. latastei and V. seoanei) to test for the contribution of ecological divergence to the development of reproductive barriers at several species traits (morphology, nuclear DNA and mitochondrial DNA). Both the nuclear and mitochondrial data show that all taxa are genetically distinct and that the sister species V. aspis and V. latastei hybridize frequently and backcross over several generations. We find that the three taxa have diverged ecologically and meet at a hybrid zone coincident with a steep ecotone between the Atlantic and Mediterranean biogeographical provinces. Integrating landscape and genetic approaches, we show that hybridization is spatially restricted to habitats that are suboptimal for parental taxa. Together, these results suggest that niche separation and adaptation to an ecological gradient confer an important barrier to gene flow among taxa that have not achieved complete reproductive isolation.

  4. Results from flight noise tests on a Viper turbojet fitted with ejector/suppressor nozzle systems

    NASA Technical Reports Server (NTRS)

    Brooks, J. R.; Mckinnon, R. A.; Johnson, E. S.

    1980-01-01

    Noise tests have been performed on a range of advanced exhaust suppressors fitted to a Viper turbojet engine with the objective of evaluating systems potentially suitable for subsonic and supersonic aircraft. A key item in the suppressor systems was an acoustically lined ejector, and tests were made with and without this ejector. Flight tests were made using an HS-125 aircraft in England and were followed by outdoor static tests at NASA Ames Research Center. In addition, acoustic and propulsion measurements were made at static, and in simulated flight conditions, with the engine installed in the Ames 40- by 80-ft wind tunnel. The paper deals mainly with the flight test results. These show that the use of a lined ejector considerably increases the attenuation obtainable using a suppressor nozzle alone and largely confirm predictions made on the basis of previous model and static tests. The maximum measured attenuation adjusted to an altitude of 500 ft was 14 EPNdB at an ideal jet velocity of 2400 ft/sec using the suppressor/ejector design intended for supersonic application. Initial propulsion performance results from the Ames wind tunnel confirm previous smaller scale propulsion results from a Douglas facility.

  5. Reproductive biology of the horned viper, Cerastes cerastes gasperettii in the central region of Saudi Arabia

    PubMed Central

    Al-Sadoon, M.K.; Kandeal, S.A.

    2015-01-01

    The reproductive biology of the horned viper, Cerastes cerastes gasperettii, in Riyadh region of Saudi Arabia was investigated over a period of one year. Study of reproductive cycle of male and female C. c. gasperettii revealed that the breeding season is relatively short (April and May). Thereafter females laid eggs by mid of July and hatching probably had taken place by the end of September. No activity was observed during winter, this may indicate just a single clutch per year. Relative testis weight to body weight was drastically increased (X¯ = 0.88%) during the peak of reproductive activity (May) where maximal expansion of seminiferous tubules was also attained during April and May (X¯ = 209 μm and 191 μm, respectively). Likewise, the ovarian activity was the highest during May where ovarian parameters were greater in terms of relative ovarian weight to body weight and ova diameter being 0.46% and 2.29 mm, respectively. Fat body weight was increased drastically just before the peak of reproductive activity then started to decline during June. It could be concluded that the harsh desert conditions and similar environments certainly affect reproductive activity of Saudi Arabian reptiles including snakes. PMID:25972758

  6. Ecological aspects of the horned viper, Cerastes cerastes gasperettii in the central region of Saudi Arabia

    PubMed Central

    Al-Sadoon, Mohammad K.; Paray, Bilal Ahmad

    2015-01-01

    Feeding ecology of any species can help us to understand its natural history, ecological requirements and approaches involved in searching for food. Feeding ecology and sexual dimorphism in the horned viper, Cerastes cerastes gasperetti collected from the Al-Thumama area, central region of Saudi Arabia was described. The gut content of Cerastes c. gasperetti mainly consisted of rodents (70%) in addition to arthropods (15%) and lizards (10%). Least sexual size dimorphism was noticed in the species in terms of total length. Significant difference was noticed between males and females in terms of two correlation points vent tail length (VT) and total length (TL) with the males attaining a larger size (P < 0.05). The mean number of the dorsal body scales, ventrals and subcaudals for the females was 102, 156 and 33 scales respectively which were significantly different from respective ones in males 95, 160 and 38 scales. There are many aspects of the feeding of this snake that remain unknown and further studies are clearly needed. PMID:26858550

  7. Measuring Large-Scale Structure at z ~ 1 with the VIPERS galaxy survey

    NASA Astrophysics Data System (ADS)

    Guzzo, Luigi

    2016-10-01

    The VIMOS Public Extragalactic Redshift Survey (VIPERS) is the largest redshift survey ever conducted with the ESO telescopes. It has used the Very Large Telescope to collect nearly 100,000 redshifts from the general galaxy population at 0.5 < z < 1.2. With a combination of volume and high sampling density that is unique for these redshifts, it allows statistical measurements of galaxy clustering and related cosmological quantities to be obtained on an equal footing with classic results from local redshift surveys. At the same time, the simple magnitude-limited selection and the wealth of ancillary photometric data provide a general view of the galaxy population, its physical properties and the relation of the latter to large-scale structure. This paper presents an overview of the galaxy clustering results obtained so far, together with their cosmological implications. Most of these are based on the ~ 55,000 galaxies forming the first public data release (PDR-1). As of January 2015, observations and data reduction are complete and the final data set of more than 90,000 redshifts is being validated and made ready for the final investigations.

  8. Lys49 myotoxin from the Brazilian lancehead pit viper elicits pain through regulated ATP release.

    PubMed

    Zhang, Chuchu; Medzihradszky, Katalin F; Sánchez, Elda E; Basbaum, Allan I; Julius, David

    2017-03-21

    Pain-producing animal venoms contain evolutionarily honed toxins that can be exploited to study and manipulate somatosensory and nociceptive signaling pathways. From a functional screen, we have identified a secreted phospholipase A2 (sPLA2)-like protein, BomoTx, from the Brazilian lancehead pit viper (Bothrops moojeni). BomoTx is closely related to a group of Lys49 myotoxins that have been shown to promote ATP release from myotubes through an unknown mechanism. Here we show that BomoTx excites a cohort of sensory neurons via ATP release and consequent activation of P2X2 and/or P2X3 purinergic receptors. We provide pharmacological and electrophysiological evidence to support pannexin hemichannels as downstream mediators of toxin-evoked ATP release. At the behavioral level, BomoTx elicits nonneurogenic inflammatory pain, thermal hyperalgesia, and mechanical allodynia, of which the latter is completely dependent on purinergic signaling. Thus, we reveal a role of regulated endogenous nucleotide release in nociception and provide a detailed mechanism of a pain-inducing Lys49 myotoxin from Bothrops species, which are responsible for the majority of snake-related deaths and injuries in Latin America.

  9. Synthesis and characterization of chitosan tripolyphosphate nanoparticles and its encapsulation efficiency containing Russell's viper snake venom.

    PubMed

    Venkatesan, C; Vimal, S; Hameed, A S Sahul

    2013-08-01

    Chitosan Tripolyphosphate (CS/TPP) nanoparticle is a biodegradable and nontoxic polysaccharide, used as a carrier for drug delivery. The morphology and particle-size measurements of the nanoparticles were studied by field emission scanning electron microscopy and Fourier Transform Infrared Spectroscopy (FTIR). This study aims to evaluate the impact of Russell's viper venom encapsulation on various factors and loading capacity, in addition to explore the physicochemical structure of nanoparticles. FTIR confirmed that tripolyphosphoric groups of TPP linked with ammonium groups of CS in the nanoparticles. Our results showed that CS can react with TPP to form stable cationic nanoparticles. The results also showed that encapsulation efficiency of venom at different concentrations of 20, 40, 60, 500, and 1000 µg/mL were achieved for CS/TPP nanoparticles at different concentrations of 1.5, 2, and 3 mg/mL. The cytotoxicity of CS/TPP nanoparticles was evaluated by MTT (-3 (4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a tetrazole) assay.

  10. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Measuring non-linear galaxy bias at z ~ 0.8

    NASA Astrophysics Data System (ADS)

    Di Porto, C.; Branchini, E.; Bel, J.; Marulli, F.; Bolzonella, M.; Cucciati, O.; de la Torre, S.; Granett, B. R.; Guzzo, L.; Marinoni, C.; Moscardini, L.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Marchetti, A.; Martizzi, D.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Viel, M.; Wolk, M.; Zamorani, G.

    2016-10-01

    Aims: We use the first release of the VImos Public Extragalactic Redshift Survey of galaxies (VIPERS) of ~50 000 objects to measure the biasing relation between galaxies and mass in the redshift range z = [ 0.5,1.1 ]. Methods: We estimate the 1-point distribution function [PDF] of VIPERS galaxies from counts in cells and, assuming a model for the mass PDF, we infer their mean bias relation. The reconstruction of the bias relation is performed through a novel method that accounts for Poisson noise, redshift distortions, inhomogeneous sky coverage. and other selection effects. With this procedure we constrain galaxy bias and its deviations from linearity down to scales as small as 4 h-1 Mpc and out to z = 1.1. Results: We detect small (up to 2%) but statistically significant (up to 3σ) deviations from linear bias. The mean biasing function is close to linear in regions above the mean density. The mean slope of the biasing relation is a proxy to the linear bias parameter. This slope increases with luminosity, which is in agreement with results of previous analyses. We detect a strong bias evolution only for z> 0.9, which is in agreement with some, but not all, previous studies. We also detect a significant increase of the bias with the scale, from 4 to 8 h-1 Mpc , now seen for the first time out to z = 1. The amplitude of non-linearity depends on redshift, luminosity, and scale, but no clear trend is detected. Owing to the large cosmic volume probed by VIPERS, we find that the mismatch between the previous estimates of bias at z ~ 1 from zCOSMOS and VVDS-Deep galaxy samples is fully accounted for by cosmic variance. Conclusions: The results of our work confirm the importance of going beyond the over-simplistic linear bias hypothesis showing that non-linearities can be accurately measured through the applications of the appropriate statistical tools to existing datasets like VIPERS. Based on observations collected at the European Southern Observatory, Paranal, Chile

  11. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Never mind the gaps: comparing techniques to restore homogeneous sky coverage

    NASA Astrophysics Data System (ADS)

    Cucciati, O.; Granett, B. R.; Branchini, E.; Marulli, F.; Iovino, A.; Moscardini, L.; Bel, J.; Cappi, A.; Peacock, J. A.; de la Torre, S.; Bolzonella, M.; Guzzo, L.; Polletta, M.; Fritz, A.; Adami, C.; Bottini, D.; Coupon, J.; Davidzon, I.; Franzetti, P.; Fumana, M.; Garilli, B.; Krywult, J.; Małek, K.; Paioro, L.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Vergani, D.; Zanichelli, A.; Di Porto, C.; Zamorani, G.

    2014-05-01

    Aims: Non-uniform sampling and gaps in sky coverage are common in galaxy redshift surveys, but these effects can degrade galaxy counts-in-cells measurements and density estimates. We carry out a comparative study of methods that aim to fill the gaps to correct for the systematic effects. Our study is motivated by the analysis of the VIMOS Public Extragalactic Redshift Survey (VIPERS), a flux-limited survey at iAB < 22.5 consisting of single-pass observations with the VLT Visible Multi-Object Spectrograph (VIMOS) with gaps representing 25% of the surveyed area and an averagesampling rate of 35%. However, our findings are generally applicable to other redshift surveys with similar observing strategies. Methods: We applied two algorithms that use photometric redshift information and assign redshifts to galaxies based upon the spectroscopic redshifts of the nearest neighbours. We compared these methods with two Bayesian methods, the Wiener filter and the Poisson-Lognormal filter. Using galaxy mock catalogues we quantified the accuracy and precision of the counts-in-cells measurements on scales of R = 5 h-1 Mpc and 8 h-1 Mpc after applying each of these methods. We further investigated how these methods perform to account for other sources of uncertainty typical of spectroscopic surveys, such as the spectroscopic redshift error and the sparse, inhomogeneous sampling rate. We analysed each of these sources separately, then all together in a mock catalogue that mimicks the full observational strategy of a VIPERS-like survey. Results: In a survey such as VIPERS, the errors in counts-in-cells measurements on R < 10 h-1 Mpc scales are dominated by the sparseness of the sample due to the single-pass observing strategy. All methods under-predict the counts in high-density regions by 20-35%, depending on the cell size, method, and underlying overdensity. This systematic bias is similar to random errors. No method outperforms the others: differences are not large, and methods

  12. The VIPERS Multi-Lambda Survey. I. UV and near-IR observations, multi-colour catalogues, and photometric redshifts

    NASA Astrophysics Data System (ADS)

    Moutard, T.; Arnouts, S.; Ilbert, O.; Coupon, J.; Hudelot, P.; Vibert, D.; Comte, V.; Conseil, S.; Davidzon, I.; Guzzo, L.; Llebaria, A.; Martin, C.; McCracken, H. J.; Milliard, B.; Morrison, G.; Schiminovich, D.; Treyer, M.; Van Werbaeke, L.

    2016-05-01

    We present observations collected in the CFHTLS-VIPERS region in the ultraviolet with the GALEX satellite (far- and near-ultraviolet channels) and in the near-infrared with the CFHT/WIRCam camera (Ks band) over an area of 22 and 27 deg2, respectively. The depth of the photometry was optimised to measure the physical properties (e.g., star formation rate, stellar masses) of all the galaxies in the VIPERS spectroscopic survey. The large volume explored by VIPERS will enable a unique investigation of the relationship between the galaxy properties and their environment (density field and cosmic web) at high redshift (0.5 ≤ z ≤ 1.2). In this paper, we present the observations, the data reductions, and the build-up of the multi-colour catalogues. The CFHTLS-T0007 (gri-χ2) images are used as reference to detect and measure the Ks-band photometry, while the T0007 u∗-selected sources are used as priors to perform the GALEX photometry based on a dedicated software (EMphot). Our final sample reaches NUVAB ~ 25 (at 5σ) and KAB ~ 22 (at 3σ). The large spectroscopic sample (~51 000 spectroscopic redshifts) allows us to highlight the robustness of our star/galaxy separation and the reliability of our photometric redshifts with a typical accuracy of σz ≤ 0.04 and a fraction of catastrophic failures η ≤ 2% down to i ~ 23. We present various tests on the Ks-band completeness and photometric redshift accuracy by comparing our results with existing overlapping deep photometric catalogues. Finally, we discuss the BzK sample of passive and active galaxies at high redshift and the evolution of galaxy morphology in the (NUV-r) vs. (r-Ks) diagram at low redshift (z ≤ 0.25) based on the high image quality of the CFHTLS. The catalogue is available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/590/A102The images, catalogues, and photometric redshifts for 1.5 million sources (down to NUV

  13. LABORATORY STUDIES ON THE POSSIBILITY OF CULEX QUINQUEFASCIATUS TO HARBOR HEPATOZOON SP. INFECTING CERASTES CERASTES CERASTES VIPER IN EGYPT.

    PubMed

    Rashdan, Nagwa A; Galal, Fatma H; Gad-Allah, Alaa F

    2015-12-01

    A successful experimental infection of Culex quinquefasciatus with Hepatozoon sp. infecting Cerastes cerastes cerastes viper was carried out under laboratory conditions of 24 +/- 3 degrees C and 60-70% R. H. The period monitored for complete sporogonic cycle was 21 days. The effect of high parasitimic blood meal was nonsignificant (P>0.05) on preoviposition period and hatchability. Meanwhile a highly significant reduction was observed in oviposition rate, number of deposited eggs, number of hatched larvae and longevity (P<0.01). On the contrary moderate infection with Hepatozoon revealed a great significant increase in fecundity (P<0.01) and a nonsignificant decrease in longevity (P>0.05)

  14. Do snakes represent the principal predatory threat to callitrichids? Fatal attack of a viper (Bothrops leucurus) on a common marmoset (Callithrix jacchus) in the Atlantic Forest of the Brazilian Northeast.

    PubMed

    Ferrari, Stephen F; Beltrão-Mendes, Raone

    2011-07-01

    A juvenile common marmoset (Callithrix jacchus) was attacked by a whitetail lancehead viper (Bothrops leucurus) while playing with other group members close to the ground at a site in northeastern Brazil. The attack was almost immediately fatal, but the viper was unable to ingest the body of the marmoset. After approximately 10 min, during which it attempted to swallow the marmoset a number of times, the viper moved away, abandoning the body. While raptors are the principal predators of callitrichids, this record reinforces the relative vulnerability of these primates to snakes in comparison with other platyrrhines, although the small number of recorded events precludes a more definitive analysis of the phenomenon.

  15. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Environmental effects shaping the galaxy stellar mass function

    NASA Astrophysics Data System (ADS)

    Davidzon, I.; Cucciati, O.; Bolzonella, M.; De Lucia, G.; Zamorani, G.; Arnouts, S.; Moutard, T.; Ilbert, O.; Garilli, B.; Scodeggio, M.; Guzzo, L.; Abbas, U.; Adami, C.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; de la Torre, S.; Di Porto, C.; Fritz, A.; Franzetti, P.; Fumana, M.; Granett, B. R.; Guennou, L.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Mellier, Y.; Moscardini, L.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.

    2016-02-01

    We exploit the first public data release of VIPERS to investigate environmental effects in the evolution of galaxies between z ~ 0.5 and 0.9. The large number of spectroscopic redshifts (more than 50 000) over an area of about 10 deg2 provides a galaxy sample with high statistical power. The accurate redshift measurements (σz = 0.00047(1 + zspec)) allow us to robustly isolate galaxies living in the lowest and highest density environments (δ< 0.7 and δ> 4, respectively) as defined in terms of spatial 3D density contrast δ. We estimate the stellar mass function of galaxies residing in these two environments and constrain the high-mass end (ℳ ≳ 1011 ℳ⊙) with unprecedented precision. We find that the galaxy stellar mass function in the densest regions has a different shape than was measured at low densities, with an enhancement of massive galaxies and a hint of a flatter (less negative) slope at z< 0.8. We normalise each mass function to the comoving volume occupied by the corresponding environment and relate estimates from different redshift bins. We observe an evolution of the stellar mass function of VIPERS galaxies in high densities, while the low-density one is nearly constant. We compare these results to semi-analytical models and find consistent environmental signatures in the simulated stellar mass functions. We discuss how the halo mass function and fraction of central/satellite galaxies depend on the environments considered, making intrinsic and environmental properties of galaxies physically coupled, hence difficult to disentangle. The evolution of our low-density regions is described well by the formalism introduced by Peng et al. (2010, ApJ, 721, 193), and is consistent with the idea that galaxies become progressively passive because of internal physical processes. The same formalism could also describe the evolution of the mass function in the high density regions, but only if a significant contribution from dry mergers is considered. Based on

  16. Nervous control of blood flow microkinetics in the infrared organs of pit vipers.

    PubMed

    Goris, R; Nakano, M; Atobe, Y; Kadota, T; Funakoshi, K; Hisajima, T; Kishida, R

    2000-10-30

    The pit organ of pit vipers contains a membrane which serves as an infrared retina, processing infrared information by the degree to which the temperature of trigeminal nerve receptors (terminal nerve masses) is raised. The receptors are arranged in a monolayer array within the pit membrane and irrigated by a capillary network which both supplies energy to the terminal nerve masses and serves as a heat exchange mechanism. This mechanism maintains the receptors at a stable temperature level to increase or decrease their sensitivity and to reduce to a minimum the afterimage effect of a moving stimulus. We used a Doppler laser blood flow meter to measure the local changes in blood flow in response to a point heat source (a small soldering iron) and to direct stimuli (red and infrared lasers). Resection of any one of the trigeminal A-delta fiber trunks innervating the pit membrane abolished blood flow response in the area innervated, but resection of the main trunk between the primary neurons and the medulla left the response intact. In addition to the A-delta fibers the pit membrane contains autonomic and sensory C-fiber innervation, but preganglionic resection of parasympathetic neurons, and chemical blocking of postganglionic fibers with atropine and capsaicin had no influence on the blood flow changes. Therefore, on the basis of the rapid response time and the similarity of the blood flow curves to electrophysiological recordings from the receptors, we surmised that all blood flow changes were due to a vasomotor reaction, modulated by the terminal nerve masses directly, resulting in a change in local heat capacity that cools the stimulated receptors back to a basal temperature.

  17. Effect of ambient temperature in neonate aspic vipers: growth, locomotor performance and defensive behaviors.

    PubMed

    Aïdam, Aurélie; Michel, Catherine Louise; Bonnet, Xavier

    2013-07-01

    The impact of temperature during incubation and gestation has been tested in various reptiles; the postnatal period has been rarely investigated however. Three groups of newborn aspic vipers (Vipera aspis) were placed under contrasted thermal regimes during 7 months: (1) a cool 23°C constant regime, (2) a warm 28°C constant regime, and (3) an optimal regime with free-access to a wide range of temperatures. Later, all the snakes were placed under hibernation conditions (6°C) during 3 months. Finally all the snakes were placed in the optimal thermal regime during 2 additional months. The total duration of the experiment was of 12 months. Body mass and feeding rates were recorded weekly, body size was measured monthly. We also assessed locomotor performance and recorded several behavioral traits (e.g., defensive and predatory behaviors). As expected, snakes raised under cool temperatures exhibited low feeding rate, growth rate, body condition, and they exhibited poor locomotor performance; they also displayed marked defensive behaviors (e.g., high number of defensive bites) whilst hesitating during longer periods to bite a prey. Such behavioral effects were detected at the end of the experiment (i.e., 5 months after exposure to contrasted thermal treatments [3 months of hibernation plus 2 months of optimal regime]), revealing long term effects. Surprisingly, growth rate and locomotor performance were not different between the two other groups, warm constant 28°C versus optimal regimes (albeit several behavioral traits differed), suggesting that the access to a wide range of ambient temperatures was not a crucial factor.

  18. Upward Altitudinal Shifts in Habitat Suitability of Mountain Vipers since the Last Glacial Maximum.

    PubMed

    Yousefi, Masoud; Ahmadi, Mohsen; Nourani, Elham; Behrooz, Roozbeh; Rajabizadeh, Mehdi; Geniez, Philippe; Kaboli, Mohammad

    2015-01-01

    We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC) that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago) and under two scenarios in the future (to 2070). These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.

  19. Azemiopsin from Azemiops feae Viper Venom, a Novel Polypeptide Ligand of Nicotinic Acetylcholine Receptor*

    PubMed Central

    Utkin, Yuri N.; Weise, Christoph; Kasheverov, Igor E.; Andreeva, Tatyana V.; Kryukova, Elena V.; Zhmak, Maxim N.; Starkov, Vladislav G.; Hoang, Ngoc Anh; Bertrand, Daniel; Ramerstorfer, Joachim; Sieghart, Werner; Thompson, Andrew J.; Lummis, Sarah C. R.; Tsetlin, Victor I.

    2012-01-01

    Azemiopsin, a novel polypeptide, was isolated from the Azemiops feae viper venom by combination of gel filtration and reverse-phase HPLC. Its amino acid sequence (DNWWPKPPHQGPRPPRPRPKP) was determined by means of Edman degradation and mass spectrometry. It consists of 21 residues and, unlike similar venom isolates, does not contain cysteine residues. According to circular dichroism measurements, this peptide adopts a β-structure. Peptide synthesis was used to verify the determined sequence and to prepare peptide in sufficient amounts to study its biological activity. Azemiopsin efficiently competed with α-bungarotoxin for binding to Torpedo nicotinic acetylcholine receptor (nAChR) (IC50 0.18 ± 0.03 μm) and with lower efficiency to human α7 nAChR (IC50 22 ± 2 μm). It dose-dependently blocked acetylcholine-induced currents in Xenopus oocytes heterologously expressing human muscle-type nAChR and was more potent against the adult form (α1β1ϵδ) than the fetal form (α1β1γδ), EC50 being 0.44 ± 0.1 μm and 1.56 ± 0.37 μm, respectively. The peptide had no effect on GABAA (α1β3γ2 or α2β3γ2) receptors at a concentration up to 100 μm or on 5-HT3 receptors at a concentration up to 10 μm. Ala scanning showed that amino acid residues at positions 3–6, 8–11, and 13–14 are essential for binding to Torpedo nAChR. In biological activity azemiopsin resembles waglerin, a disulfide-containing peptide from the Tropidechis wagleri venom, shares with it a homologous C-terminal hexapeptide, but is the first natural toxin that blocks nAChRs and does not possess disulfide bridges. PMID:22613724

  20. Upward Altitudinal Shifts in Habitat Suitability of Mountain Vipers since the Last Glacial Maximum

    PubMed Central

    Yousefi, Masoud; Ahmadi, Mohsen; Nourani, Elham; Behrooz, Roozbeh; Rajabizadeh, Mehdi; Geniez, Philippe; Kaboli, Mohammad

    2015-01-01

    We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC) that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago) and under two scenarios in the future (to 2070). These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region. PMID:26367126

  1. Viper venom hyaluronidase and its potential inhibitor analysis: a multipronged computational investigation.

    PubMed

    Sivaramakrishnan, V; Ilamathi, M; Girish, K S; Kemparaju, K; Rangappa, K S; Dhananjaya, Bhadrapura Lakkappa

    2016-07-11

    Viper venom hyaluronidase (VV-HYA) inhibitors have long been used as therapeutic agents for arresting the local and systemic effects caused during its envenomation. Henceforth, to understand its structural features and also to identify the best potential inhibitor against it the present computational study was undertaken. Structure-based homology modeling of VV-HYA followed by its docking and free energy-based ranking analysis of ligand, the MD simulations of the lead complex was also performed. The sequence analysis and homology modeling of VV-HYA revealed a distorted (β/α)8 folding as in the case of hydrolases family of proteins. Molecular docking of the resultant 3D structure of VV-HYA with known inhibitors (compounds 1-25) revealed the importance of molecular recognition of hotspot residues (Tyr 75, Arg 288, and Trp 321) other than that of the active site residues. It also revealed that Trp 321 of VV-HYA is highly important for mediating π-π interactions with ligands. In addition, the molecular docking and comparative free energy binding analysis was investigated for the VV-HYA inhibitors (compounds 1-25). Both molecular docking and relative free energy binding analysis clearly confirmed the identification of sodium chromoglycate (compound 1) as the best potential inhibitor against VV-HYA. Molecular dynamics simulations additionally confirmed the stability of their binding interactions. Further, the information obtained from this work is believed to serve as an impetus for future rational designing of new novel VV-HYA inhibitors with improved activity and selectivity.

  2. Viperatoxin-II: A novel viper venom protein as an effective bactericidal agent.

    PubMed

    Samy, Ramar Perumal; Stiles, Bradley G; Chinnathambi, Arunachalam; Zayed, M E; Alharbi, Sulaiman Ali; Franco, Octavio Luiz; Rowan, Edward G; Kumar, Alan Prem; Lim, Lina H K; Sethi, Gautam

    2015-01-01

    Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have become a rising threat to public health. There is an urgent need for development of promising new therapeutic agents against drug resistant bacteria like S. aureus. This report discusses purification and characterization of proteins from Indian Russell's viper snake venom. Novel 15-kDa proteins called "Viperatoxin" (VipTx-I and VipTx-II) were extracted from the whole venom and evaluated using in vitro antimicrobial experiments. The N-terminal amino acid sequence of "Viperatoxin" showed high sequence homology to daboiatoxin isolated from the same venom and also matched phospholipase A2 (PLA2) enzymes isolated from other snake venoms. In an in vitro plate assay, VipTx-II but not VipTx-I showed strong antimicrobial effects against S. aureus and Burkholderia pseudomallei (KHW & TES), Proteus vulgaris and P. mirabilis. The VipTx-II was further tested by a broth-dilution assay at 100-3.1 μg/ml concentrations. The most potent bactericidal effect was found at the lowest dilutions (MICs of 6.25 μg/ml) against B. pseudomallei, S. aureus and P. vulgaris (MICs of 12.25 μg/ml). Electron microscopic investigation revealed that the protein-induced bactericidal potency was closely associated with pore formation and membrane damage, even at the lowest concentrations (<20 μg/ml). The toxin caused a low level of cytotoxic effects as observed in human (THP-1) cells at higher concentrations. Molecular weight determinations of VipTx-II by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed one major, along with a few minor bands. The results indicate that VipTx-II plays a significant role in bactericidal and membrane damaging effects in vitro. Non-cytotoxic properties on human cells highlight it as a promising candidate for further evaluation of antimicrobial potential in vivo.

  3. Frequent and potentially fatal envenoming by hump-nosed pit vipers (Hypnale hypnale and H. nepa) in Sri Lanka: lack of effective antivenom.

    PubMed

    Ariaratnam, C A; Thuraisingam, V; Kularatne, S A M; Sheriff, M H R; Theakston, R D G; de Silva, A; Warrell, D A

    2008-11-01

    In a prospective study of snake bites involving 10 hospitals in Sri Lanka, 302 (35%) of 860 patients with bites by identified snakes proved to have been bitten by hump-nosed pit vipers (301 by Hypnale hypnale and 1 by H. nepa). Most victims were males aged between 11 years and 50 years who had been bitten on their feet or ankles while walking at night close to their homes. There was local swelling in 276 (91%) and local necrosis in 48 (16%). Eleven (4%) required amputation of fingers or toes and 12 (4%) received skin grafts. In 117 patients (39%) blood incoagulability was first detected between 15 min and 48 h after the bite, and in 116 of them this was present on admission to hospital. Spontaneous systemic bleeding was observed in 55 patients (18%). Acute renal failure developed in 10%, five of whom died to give an overall case fatality rate of 1.7%. Thus, bites by hump-nosed pit vipers can cause debilitating local and fatal systemic envenoming. In Sri Lanka and southwestern India where bites by these snakes are common, the only available antivenoms (raised against cobra, krait, Russell's viper and saw-scaled viper venoms) are ineffective and carry a high risk of reactions.

  4. African Aesthetics

    ERIC Educational Resources Information Center

    Abiodun, Rowland

    2001-01-01

    No single traditional discipline can adequately supply answers to the many unresolved questions in African art history. Because of the aesthetic, cultural, historical, and, not infrequently, political biases, already built into the conception and development of Western art history, the discipline of art history as defined and practiced in the West…

  5. African Pentecostalism

    ERIC Educational Resources Information Center

    Garrard, David J.

    2009-01-01

    The diversity of African Pentecostalism, its early colonial and missionary history and its current characteristics are described and analysed. Reference is made to methods of training and forms of leadership, and suggestions are made about the reasons for its growth and persistence. (Contains 19 notes.)

  6. Live-birth in vipers (Viperidae) is a key innovation and adaptation to global cooling during the Cenozoic.

    PubMed

    Lynch, Vincent J

    2009-09-01

    The identification of adaptations and key innovations has long interested biologists because they confer on organisms the ability to exploit previously unavailable ecological resources and respond to novel selective pressures. Although it can be extremely difficult to test for the effects of a character on the rate of lineage diversification, the convergent evolution of a character in multiple lineages provides an excellent opportunity to test for the effect of that character on lineage diversification. Here, I examine the effect of parity mode on the diversification of vipers, which have independently evolved viviparity in at least 13 lineages. I find strong statistical evidence that viviparous species diversify at a greater rate than oviparous species and correlate major decreases in the diversification rate of oviparous species with periods of global cooling, such as the Oligocene. These results suggest that the evolution of viviparity buffered live-bearing species against the negative effects of global climate change during the Cenozoic, and was a key innovation in the evolution and diversification of live-bearing vipers.

  7. Venomics of Tropidolaemus wagleri, the sexually dimorphic temple pit viper: Unveiling a deeply conserved atypical toxin arsenal

    PubMed Central

    Tan, Choo Hock; Tan, Kae Yi; Yap, Michelle Khai Khun; Tan, Nget Hong

    2017-01-01

    Tropidolaemus wagleri (temple pit viper) is a medically important snake in Southeast Asia. It displays distinct sexual dimorphism and prey specificity, however its venomics and inter-sex venom variation have not been thoroughly investigated. Applying reverse-phase HPLC, we demonstrated that the venom profiles were not significantly affected by sex and geographical locality (Peninsular Malaya, insular Penang, insular Sumatra) of the snakes. Essentially, venoms of both sexes share comparable intravenous median lethal dose (LD50) (0.56–0.63 μg/g) and cause neurotoxic envenomation in mice. LCMS/MS identified six waglerin forms as the predominant lethal principles, comprising 38.2% of total venom proteins. Fourteen other toxin-protein families identified include phospholipase A2, serine proteinase, snaclec and metalloproteinase. In mice, HPLC fractions containing these proteins showed insignificant contribution to the overall venom lethality. Besides, the unique elution pattern of approximately 34.5% of non-lethal, low molecular mass proteins (3–5 kDa) on HPLC could be potential biomarker for this primitive crotalid species. Together, the study unveiled the venom proteome of T. wagleri that is atypical among many pit vipers as it comprises abundant neurotoxic peptides (waglerins) but little hemotoxic proteinases. The findings also revealed that the venom is relatively well conserved intraspecifically despite the drastic morphological differences between sexes. PMID:28240232

  8. Quantitative Proteomic Analysis of Venoms from Russian Vipers of Pelias Group: Phospholipases A2 are the Main Venom Components

    PubMed Central

    Kovalchuk, Sergey I.; Ziganshin, Rustam H.; Starkov, Vladislav G.; Tsetlin, Victor I.; Utkin, Yuri N.

    2016-01-01

    Venoms of most Russian viper species are poorly characterized. Here, by quantitative chromato-mass-spectrometry, we analyzed protein and peptide compositions of venoms from four Vipera species (V. kaznakovi, V. renardi, V. orlovi and V. nikolskii) inhabiting different regions of Russia. In all these species, the main components were phospholipases A2, their content ranging from 24% in V. orlovi to 65% in V. nikolskii. Altogether, enzyme content in venom of V. nikolskii reached ~85%. Among the non-enzymatic proteins, the most abundant were disintegrins (14%) in the V. renardi venom, C-type lectin like (12.5%) in V. kaznakovi, cysteine-rich venom proteins (12%) in V. orlovi and venom endothelial growth factors (8%) in V. nikolskii. In total, 210 proteins and 512 endogenous peptides were identified in the four viper venoms. They represented 14 snake venom protein families, most of which were found in the venoms of Vipera snakes previously. However, phospholipase B and nucleotide degrading enzymes were reported here for the first time. Compositions of V. kaznakovi and V. orlovi venoms were described for the first time and showed the greatest similarity among the four venoms studied, which probably reflected close relationship between these species within the “kaznakovi” complex. PMID:27077884

  9. The VIMOS Public Extragalactic Redshift Survey (VIPERS): galaxy segregation inside filaments at z ≃ 0.7

    NASA Astrophysics Data System (ADS)

    Malavasi, N.; Arnouts, S.; Vibert, D.; de la Torre, S.; Moutard, T.; Pichon, C.; Davidzon, I.; Kraljic, K.; Bolzonella, M.; Guzzo, L.; Garilli, B.; Scodeggio, M.; Granett, B. R.; Abbas, U.; Adami, C.; Bottini, D.; Cappi, A.; Cucciati, O.; Franzetti, P.; Fritz, A.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Polletta, M.; Pollo, A.; Tasca, L.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Bel, J.; Branchini, E.; Coupon, J.; De Lucia, G.; Dubois, Y.; Hawken, A.; Ilbert, O.; Laigle, C.; Moscardini, L.; Sousbie, T.; Treyer, M.; Zamorani, G.

    2017-03-01

    We present the first quantitative detection of large-scale filamentary structure at z ≃ 0.7 in the large cosmological volume probed by the VIMOS Public Extragalactic Redshift Survey (VIPERS). We use simulations to show the capability of VIPERS to recover robust topological features in the galaxy distribution, in particular the filamentary network. We then investigate how galaxies with different stellar masses and stellar activities are distributed around the filaments, and find a significant segregation, with the most massive or quiescent galaxies being closer to the filament axis than less massive or active galaxies. The signal persists even after downweighting the contribution of peak regions. Our results suggest that massive and quiescent galaxies assemble their stellar mass through successive mergers during their migration along filaments towards the nodes of the cosmic web. On the other hand, low-mass star-forming galaxies prefer the outer edge of filaments, a vorticity-rich region dominated by smooth accretion, as predicted by the recent spin alignment theory. This emphasizes the role of large-scale cosmic flows in shaping galaxy properties.

  10. Venomics of Tropidolaemus wagleri, the sexually dimorphic temple pit viper: Unveiling a deeply conserved atypical toxin arsenal.

    PubMed

    Tan, Choo Hock; Tan, Kae Yi; Yap, Michelle Khai Khun; Tan, Nget Hong

    2017-02-27

    Tropidolaemus wagleri (temple pit viper) is a medically important snake in Southeast Asia. It displays distinct sexual dimorphism and prey specificity, however its venomics and inter-sex venom variation have not been thoroughly investigated. Applying reverse-phase HPLC, we demonstrated that the venom profiles were not significantly affected by sex and geographical locality (Peninsular Malaya, insular Penang, insular Sumatra) of the snakes. Essentially, venoms of both sexes share comparable intravenous median lethal dose (LD50) (0.56-0.63 μg/g) and cause neurotoxic envenomation in mice. LCMS/MS identified six waglerin forms as the predominant lethal principles, comprising 38.2% of total venom proteins. Fourteen other toxin-protein families identified include phospholipase A2, serine proteinase, snaclec and metalloproteinase. In mice, HPLC fractions containing these proteins showed insignificant contribution to the overall venom lethality. Besides, the unique elution pattern of approximately 34.5% of non-lethal, low molecular mass proteins (3-5 kDa) on HPLC could be potential biomarker for this primitive crotalid species. Together, the study unveiled the venom proteome of T. wagleri that is atypical among many pit vipers as it comprises abundant neurotoxic peptides (waglerins) but little hemotoxic proteinases. The findings also revealed that the venom is relatively well conserved intraspecifically despite the drastic morphological differences between sexes.

  11. Quantitative Proteomic Analysis of Venoms from Russian Vipers of Pelias Group: Phospholipases A₂ are the Main Venom Components.

    PubMed

    Kovalchuk, Sergey I; Ziganshin, Rustam H; Starkov, Vladislav G; Tsetlin, Victor I; Utkin, Yuri N

    2016-04-12

    Venoms of most Russian viper species are poorly characterized. Here, by quantitative chromato-mass-spectrometry, we analyzed protein and peptide compositions of venoms from four Vipera species (V. kaznakovi, V. renardi, V. orlovi and V. nikolskii) inhabiting different regions of Russia. In all these species, the main components were phospholipases A₂, their content ranging from 24% in V. orlovi to 65% in V. nikolskii. Altogether, enzyme content in venom of V. nikolskii reached ~85%. Among the non-enzymatic proteins, the most abundant were disintegrins (14%) in the V. renardi venom, C-type lectin like (12.5%) in V. kaznakovi, cysteine-rich venom proteins (12%) in V. orlovi and venom endothelial growth factors (8%) in V. nikolskii. In total, 210 proteins and 512 endogenous peptides were identified in the four viper venoms. They represented 14 snake venom protein families, most of which were found in the venoms of Vipera snakes previously. However, phospholipase B and nucleotide degrading enzymes were reported here for the first time. Compositions of V. kaznakovi and V. orlovi venoms were described for the first time and showed the greatest similarity among the four venoms studied, which probably reflected close relationship between these species within the "kaznakovi" complex.

  12. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Ωm0 from the galaxy clustering ratio measured at z ~ 1

    NASA Astrophysics Data System (ADS)

    Bel, J.; Marinoni, C.; Granett, B. R.; Guzzo, L.; Peacock, J. A.; Branchini, E.; Cucciati, O.; de la Torre, S.; Iovino, A.; Percival, W. J.; Steigerwald, H.; Abbas, U.; Adami, C.; Arnouts, S.; Bolzonella, M.; Bottini, D.; Cappi, A.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Phleps, S.; Wolk, M.; Zamorani, G.

    2014-03-01

    We use a sample of about 22 000 galaxies at 0.65 < z < 1.2 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) Public Data Release 1 (PDR-1) catalogue, to constrain the cosmological model through a measurement of the galaxy clustering ratio ηg,R. This statistic has favourable properties, which is defined as the ratio of two quantities characterizing the smoothed density field in spheres of a given radius R: the value of its correlation function on a multiple of this scale, ξ(nR), and its variance σ2(R). For sufficiently large values of R, this is a universal number, which captures 2-point clustering information independently of the linear bias and linear redshift-space distortions of the specific galaxy tracers. In this paper, we discuss how to extend the application of ηg,R to quasi-linear scales and how to control and remove observational selection effects, which are typical of redshift surveys as VIPERS, in detail. We verify the accuracy and efficiency of these procedures using mock catalogues that match the survey selection process. These results show the robustness of ηg,R to non-linearities and observational effects, which is related to its very definition as a ratio of quantities that are similarly affected. At an effective redshift z = 0.93, we measured the value ηg,R(15) = 0.141 ± 0.013 at R = 5h-1 Mpc. Within a flat ΛCDM cosmology and by including the best available priors on H0, ns and baryon density, we obtain a matter density parameter at the current epoch Ωm,0 = 0.270-0.025+0.029. In addition to the great precision achieved on our estimation of Ωm using VIPERS PDR-1, this result is remarkable because it appears to be in good agreement with a recent estimate at z ≃ 0.3, which was obtained by applying the same technique to the SDSS-LRG catalogue. It, therefore, supports the robustness of the present analysis. Moreover, the combination of these two measurements at z ~ 0.3 and z ~ 0.9 provides us with a very precise estimate of Ωm,0

  13. Neurotoxicity in Sri Lankan Russell's Viper (Daboia russelii) Envenoming is Primarily due to U1-viperitoxin-Dr1a, a Pre-Synaptic Neurotoxin.

    PubMed

    Silva, Anjana; Kuruppu, Sanjaya; Othman, Iekhsan; Goode, Robert J A; Hodgson, Wayne C; Isbister, Geoffrey K

    2017-01-01

    Russell's vipers are snakes of major medical importance in Asia. Russell's viper (Daboia russelii) envenoming in Sri Lanka and South India leads to a unique, mild neuromuscular paralysis, not seen in other parts of the world where the snake is found. This study aimed to identify and pharmacologically characterise the major neurotoxic components of Sri Lankan Russell's viper venom. Venom was fractionated using size exclusion chromatography and reverse-phase high-performance liquid chromatography (RP-HPLC). In vitro neurotoxicities of the venoms, fractions and isolated toxins were measured using chick biventer and rat hemidiaphragm preparations. A phospholipase A2 (PLA2) toxin, U1-viperitoxin-Dr1a (13.6 kDa), which constitutes 19.2 % of the crude venom, was isolated and purified using HPLC. U1-viperitoxin-Dr1a produced concentration-dependent in vitro neurotoxicity abolishing indirect twitches in the chick biventer nerve-muscle preparation, with a t 90 of 55 ± 7 min only at 1 μM. The toxin did not abolish responses to acetylcholine and carbachol indicating pre-synaptic neurotoxicity. Venom, in the absence of U1-viperitoxin-Dr1a, did not induce in vitro neurotoxicity. Indian polyvalent antivenom, at the recommended concentration, only partially prevented the neurotoxic effects of U1-viperitoxin-Dr1a. Liquid chromatography mass spectrometry analysis confirmed that U1-viperitoxin-Dr1a was the basic S-type PLA2 toxin previously identified from this venom (NCBI-GI: 298351762; SwissProt: P86368). The present study demonstrates that neurotoxicity following Sri Lankan Russell's viper envenoming is primarily due to the pre-synaptic neurotoxin U1-viperitoxin-Dr1a. Mild neurotoxicity observed in severely envenomed Sri Lankan Russell's viper bites is most likely due to the low potency of U1-viperitoxin-Dr1a, despite its high relative abundance in the venom.

  14. African-American Biography.

    ERIC Educational Resources Information Center

    Martin, Ron

    1995-01-01

    Suggests sources of information for African American History Month for library media specialists who work with students in grades four through eight. Gale Research's "African-American Reference Library," which includes "African-America Biography,""African-American Chronology," and "African-American Almanac,"…

  15. African Trypanosomiasis

    DTIC Science & Technology

    2011-06-01

    infection by protozoan hemo- flagellates of the Trypanosoma brucei complex, 2 subspe- cies of which cause disease in humans: Trypanosoma bru- cei gambiense...public release; distribution unlimited 13. SUPPLEMENTARY NOTES See also ADA545141. Chapter 3 from e-book, Topics on the Pathology of Protozoan and...the brief ferry crossing. 2 3 • Topics on The paThology of proTozoan and invasive arThropod diseases Three severe epidemics of African trypanosomiasis

  16. Viperatoxin-II: A novel viper venom protein as an effective bactericidal agent

    PubMed Central

    Samy, Ramar Perumal; Stiles, Bradley G.; Chinnathambi, Arunachalam; Zayed, M.E.; Alharbi, Sulaiman Ali; Franco, Octavio Luiz; Rowan, Edward G.; Kumar, Alan Prem; Lim, Lina H.K.; Sethi, Gautam

    2015-01-01

    Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have become a rising threat to public health. There is an urgent need for development of promising new therapeutic agents against drug resistant bacteria like S. aureus. This report discusses purification and characterization of proteins from Indian Russell’s viper snake venom. Novel 15-kDa proteins called “Viperatoxin” (VipTx-I and VipTx-II) were extracted from the whole venom and evaluated using in vitro antimicrobial experiments. The N-terminal amino acid sequence of “Viperatoxin” showed high sequence homology to daboiatoxin isolated from the same venom and also matched phospholipase A2 (PLA2) enzymes isolated from other snake venoms. In an in vitro plate assay, VipTx-II but not VipTx-I showed strong antimicrobial effects against S. aureus and Burkholderia pseudomallei (KHW & TES), Proteus vulgaris and P. mirabilis. The VipTx-II was further tested by a broth-dilution assay at 100–3.1 μg/ml concentrations. The most potent bactericidal effect was found at the lowest dilutions (MICs of 6.25 μg/ml) against B. pseudomallei, S. aureus and P. vulgaris (MICs of 12.25 μg/ml). Electron microscopic investigation revealed that the protein-induced bactericidal potency was closely associated with pore formation and membrane damage, even at the lowest concentrations (<20 μg/ml). The toxin caused a low level of cytotoxic effects as observed in human (THP-1) cells at higher concentrations. Molecular weight determinations of VipTx-II by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed one major, along with a few minor bands. The results indicate that VipTx-II plays a significant role in bactericidal and membrane damaging effects in vitro. Non-cytotoxic properties on human cells highlight it as a promising candidate for further evaluation of antimicrobial potential in vivo. PMID:26793432

  17. Combined snake venomics and venom gland transcriptomic analysis of the ocellated carpet viper, Echis ocellatus.

    PubMed

    Wagstaff, Simon C; Sanz, Libia; Juárez, Paula; Harrison, Robert A; Calvete, Juan J

    2009-01-30

    Snakebite in Africa causes thousands of deaths annually and considerable permanent physical disability. The saw-scaled viper, Echis ocellatus, represents the single most medically important snake species in West Africa. To provide a detailed compositional analysis of the venom of E. ocellatus for designing novel toxin-specific immunotherapy and to delineate sequence structure-function relationships of individual toxins, we characterised the venom proteome and the venom gland transcriptome. Whole E. ocellatus venom was fractionated by reverse-phase HPLC, followed by analysis of each chromatographic fraction using a combination of SDS-PAGE, N-terminal sequencing, MALDI-TOF mass fingerprinting, and CID-MS/MS of tryptic peptides. This analysis identified around 35 distinct proteins of molecular masses in the range of 5.5-110 kDa belonging to 8 different toxin families (disintegrin, DC-fragment, phospholipase A(2), cysteine-rich secretory protein, serine proteinase, C-type lectin, l-amino acid oxidase, and Zn(2+)-dependent metalloprotease). Comparison of the toxin composition of E. ocellatus venom determined using a proteomic approach, with the predicted proteome derived from assembly of 1000 EST sequences from a E. ocellatus venom gland cDNA library, shows some differences. Most notably, peptides derived from 26% of the venom proteins could not be ascribed an exact match in the transcriptome. Similarly, 64 (67%) out of the 95 putative toxin clusters reported in the transcriptome did not match to peptides detected in the venom proteome. These data suggest that the final composition of venom is influenced by transcriptional and post-translational mechanisms that may be more complex than previously appreciated. This, in turn, emphasises the value of combining proteomic and transcriptomic approaches to acquire a more complete understanding of the precise composition of snake venom, than would be gleaned from using one analysis alone. From a clinical perspective, the large

  18. Pharmacokinetic behavior of enrofloxacin and its metabolite ciprofloxacin in urutu pit vipers (Bothrops alternatus) after intramuscular administration.

    PubMed

    Waxman, Samanta; Prados, Ana Paula; de Lucas, José Julio; San Andrés, Manuel Ignacion; Regner, Pablo; de Oliveira, Vanesa Costa; de Roodt, Adolfo; Rodríguez, Casilda

    2014-03-01

    Enrofloxacin is widely used in veterinary medicine and is an important alternative to treating bacterial infections, which play an important role as causes of disease and death in captive snakes. Its extralabel use in nontraditional species has been related to its excellent pharmacokinetic and antimicrobial characteristics. This can be demonstrated by its activity against gram-negative organisms implicated in serious infectious diseases of reptile species with a rapid and concentration-dependent bactericidal effect and a large volume of distribution. Pharmacokinetic parameters for enrofloxacin were investigated in seven urutu pit vipers (Bothrops alternatus), following intramuscular injections of 10 mg/kg. The plasma concentrations of enrofloxacin and its metabolite, ciprofloxacin, were measured using high-performance liquid chromatography. Blood samples were collected from the ventral coccygeal veins at 0.5, 1, 2, 4, 8, 12, 24, 36, 48, 72, 96, 108, and 168 hr. The kinetic behavior was characterized by a relatively slow absorption (time of maximal plasma concentration = 4.50 +/- 3.45 hr) with peak plasma concentration of 4.81 +/- 1.12 microg/ml. The long half-life during the terminal elimination phase (t1/2 lambda = 27.91 +/- 7.55 hr) of enrofloxacin after intramuscular administration, calculated in the present study, could suggest that the antibiotic is eliminated relatively slowly and/or the presence of a slow absorption in urutu pit vipers. Ciprofloxacin reached a peak plasma concentration of 0.35 microg/ml at 13.45 hr, and the fraction of enrofloxacin metabolized to ciprofloxacin was 13.06%. If enrofloxacin's minimum inhibitory concentration (MIC90) values of 0.5 microg/ml were used, the ratios AUC(e+c): MIC90 (276 +/- 67 hr) and Cmax(e+c): MIC90 (10 +/- 2) reach the proposed threshold values (125 hr and 10, respectively) for optimized efficacy and minimized resistance development when treating infections caused by Pseudomonas. The administration of 10 mg/kg of

  19. The formation and build-up of the red-sequence over the past 9 Gyr in VIPERS

    NASA Astrophysics Data System (ADS)

    Fritz, Alexander; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Branchini, E.; Burden, A.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Di Porto, C.; Franzetti, P.; Fumana, M.; Garilli, B.; Granett, B. R.; Guzzo, L.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marchetti, A.; Marinoni, C.; Marulli, F.; McCracken, H. J.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Paioro, L.; Peacock, J. A.; Percival, W. J.; Polletta, M.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zamorani, G.; Zanichelli, A.; VIPERS Team

    2015-02-01

    We present the Luminosity Function (LF) and Colour-Magnitude Relation (CMR) using ~45000 galaxies drawn from the VIMOS Public Extragalactic Redshift Survey (VIPERS). Using different selection criteria, we define several samples of early-type galaxies and explore their impact on the evolution of the red-sequence (RS) and the effects of dust. Our results suggest a rapid build-up of the RS within a short time scale. We find a rise in the number density of early-type galaxies and a strong evolution in LF and CMR. Massive galaxies exist already 9 Gyr ago and experience an efficient quenching of their star formation at z = 1, followed by a passive evolution with only limited merging activity. In contrast, low-mass galaxies indicate a different mass assembly history and cause a slow build-up of the CMR over cosmic time.

  20. Bacteriological studies of the venom and mouth cavities of wild Malayan pit vipers (Calloselasma rhodostoma) in southern Thailand.

    PubMed

    Theakston, R D; Phillips, R E; Looareesuwan, S; Echeverria, P; Makin, T; Warrell, D A

    1990-01-01

    Venom and oropharyngeal swabs from freshly captured Malayan pit vipers (Calloselasma rhodostoma) in southern Thailand and captive specimens in England were cultured aerobically and anaerobically to identify the bacterial flora which might contaminate wounds inflicted by bites of this species. The snakes' mouths contained a wider range of organisms than their venoms, especially gut-related Gram-negative rods such as Enterobacter and Pseudomonas species and some staphylococci and clostridia. There were fewer positive cultures from captive snakes. C. rhodostoma venom inhibited the growth of group A streptococci and, to a lesser extent, that of Staphylococcus aureus and Clostridium perfringens but not that of 2 Gram-negative organisms. Secondary bacterial infection is an important complication of snake bite, especially of necrotic wounds. A combination of gentamicin with benzyl penicillin would have prevented infection with, or treated, most of the bacteria isolated from snake venoms and mouths in Thailand.

  1. Vipericidins: a novel family of cathelicidin-related peptides from the venom gland of South American pit vipers.

    PubMed

    Falcao, C B; de La Torre, B G; Pérez-Peinado, C; Barron, A E; Andreu, D; Rádis-Baptista, G

    2014-11-01

    Cathelicidins are phylogenetically ancient, pleiotropic host defense peptides-also called antimicrobial peptides (AMPs)-expressed in numerous life forms for innate immunity. Since even the jawless hagfish expresses cathelicidins, these genetically encoded host defense peptides are at least 400 million years old. More recently, cathelicidins with varying antipathogenic activities and cytotoxicities were discovered in the venoms of poisonous snakes; for these creatures, cathelicidins may also serve as weapons against prey and predators, as well as for innate immunity. We report herein the expression of orthologous cathelicidin genes in the venoms of four different South American pit vipers (Bothrops atrox, Bothrops lutzi, Crotalus durissus terrificus, and Lachesis muta rhombeata)-distant relatives of Asian cobras and kraits, previously shown to express cathelicidins-and an elapid, Pseudonaja textilis. We identified six novel, genetically encoded peptides: four from pit vipers, collectively named vipericidins, and two from the elapid. These new venom-derived cathelicidins exhibited potent killing activity against a number of bacterial strains (S. pyogenes, A. baumannii, E. faecalis, S. aureus, E. coli, K. pneumoniae, and P. aeruginosa), mostly with relatively less potent hemolysis, indicating their possible usefulness as lead structures for the development of new anti-infective agents. It is worth noting that these South American snake venom peptides are comparable in cytotoxicity (e.g., hemolysis) to human cathelicidin LL-37, and much lower than other membrane-active peptides such as mastoparan 7 and melittin from bee venom. Overall, the excellent bactericidal profile of vipericidins suggests they are a promising template for the development of broad-spectrum peptide antibiotics.

  2. VIPERS: Unveiling the Combined Evolution of Galaxies and Large Scale Structure at 0.5≤z ≤1.2

    NASA Astrophysics Data System (ADS)

    Iovino, A.; Vipers Team

    2016-10-01

    The VIMOS Public Extragalactic Redshift Survey (VIPERS) is the largest redshift survey ever conducted with the ESO telescopes. It has used the Very Large Telescope to collect nearly 100,000 redshifts from the general galaxy population at 0.5≤ z ≤1.2. With a combination of volume and sampling density that is unique for these redshifts, VIPERS allows statistical measurements of galaxy clustering and related cosmological quantities to be obtained on an equal footing with classic results from local redshift surveys. At the same time, the broad selection function and ancillary photometric data provide detailed information on the physical properties of the galaxy population and their relation to large-scale structure. This talk presents an overview of the results obtained so far, mostly based on the ˜ 55,000 galaxies forming the first public data release (PDR-1).

  3. [Molecular cloning and analysis of cDNA sequences encoding serine proteinase and Kunitz type inhibitor in venom gland of Vipera nikolskii viper].

    PubMed

    Ramazanova, A S; Fil'kin, S Iu; Starkov, V G; Utkin, Iu N

    2011-01-01

    Serine proteinases and Kunitz type inhibitors are widely represented in venoms of snakes from different genera. During the study of the venoms from snakes inhabiting Russia we have cloned cDNAs encoding new proteins belonging to these protein families. Thus, a new serine proteinase called nikobin was identified in the venom gland of Vipera nikolskii viper. By amino acid sequence deduced from the cDNA sequence, nikobin differs from serine proteinases identified in other snake species. Nikobin amino acid sequence contains 15 unique substitutions. This is the first serine proteinase of viper from Vipera genus for which a complete amino acid sequence established. The cDNA encoding Kunitz type inhibitor was also cloned. The deduced amino acid sequence of inhibitor is homologous to those of other proteins from that snakes of Vipera genus. However there are several unusual amino acid substitutions that might result in the change of biological activity of inhibitor.

  4. African Outreach Workshop 1974.

    ERIC Educational Resources Information Center

    Schmidt, Nancy J.

    This report discusses the 1974 African Outreach Workshop planned and coordinated by the African Studies Program at the University of Illinois at Urbana-Champaign. Its major aim was to assist teachers in developing curriculum units on African using materials available in their local community. A second aim was for the African Studies Program to…

  5. Africans in America.

    ERIC Educational Resources Information Center

    Hart, Ayanna; Spangler, Earl

    This book introduces African-American history and culture to children. The first Africans in America came from many different regions and cultures, but became united in this country by being black, African, and slaves. Once in America, Africans began a long struggle for freedom which still continues. Slavery, the Civil War, emancipation, and the…

  6. The VIMOS Public Extragalactic Redshift Survey (VIPERS) . Galaxy clustering and redshift-space distortions at z ≃ 0.8 in the first data release

    NASA Astrophysics Data System (ADS)

    de la Torre, S.; Guzzo, L.; Peacock, J. A.; Branchini, E.; Iovino, A.; Granett, B. R.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Moscardini, L.; Paioro, L.; Percival, W. J.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Monaco, P.; Nichol, R. C.; Phleps, S.; Wolk, M.; Zamorani, G.

    2013-09-01

    We present the general real- and redshift-space clustering properties of galaxies as measured in the first data release of the VIPERS survey. VIPERS is a large redshift survey designed to probe in detail the distant Universe and its large-scale structure at 0.5 < z < 1.2. We describe in this analysis the global properties of the sample and discuss the survey completeness and associated corrections. This sample allows us to measure the galaxy clustering with an unprecedented accuracy at these redshifts. From the redshift-space distortions observed in the galaxy clustering pattern we provide a first measurement of the growth rate of structure at z = 0.8: fσ8 = 0.47 ± 0.08. This is completely consistent with the predictions of standard cosmological models based on Einstein gravity, although this measurement alone does not discriminate between different gravity models. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programmes 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/

  7. The short interspersed repetitive element of Trypanosoma cruzi, SIRE, is part of VIPER, an unusual retroelement related to long terminal repeat retrotransposons

    PubMed Central

    Vázquez, Martín; Ben-Dov, Claudia; Lorenzi, Hernan; Moore, Troy; Schijman, Alejandro; Levin, Mariano J.

    2000-01-01

    The short interspersed repetitive element (SIRE) of Trypanosoma cruzi was first detected when comparing the sequences of loci that encode the TcP2β genes. It is present in about 1,500–3,000 copies per genome, depending on the strain, and it is distributed in all chromosomes. An initial analysis of SIRE sequences from 21 genomic fragments allowed us to derive a consensus nucleotide sequence and structure for the element, consisting of three regions (I, II, and III) each harboring distinctive features. Analysis of 158 transcribed SIREs demonstrates that the consensus is highly conserved. The sequences of 51 cDNAs show that SIRE is included in the 3′ end of several mRNAs, always transcribed from the sense strand, contributing the polyadenylation site in 63% of the cases. This study led to the characterization of VIPER (vestigial interposed retroelement), a 2,326-bp-long unusual retroelement. VIPER's 5′ end is formed by the first 182 bp of SIRE, whereas its 3′ end is formed by the last 220 bp of the element. Both SIRE moieties are connected by a 1,924-bp-long fragment that carries a unique ORF encoding a complete reverse transcriptase-RNase H gene whose 15 C-terminal amino acids derive from codons specified by SIRE's region II. The amino acid sequence of VIPER's reverse transcriptase-RNase H shares significant homology to that of long terminal repeat retrotransposons. The fact that SIRE and VIPER sequences are found only in the T. cruzi genome may be of relevance for studies concerning the evolution and the genome flexibility of this protozoan parasite. PMID:10688909

  8. Purification, sequencing, and phylogenetic analyses of novel Lys-49 phospholipases A(2) from the venoms of rattlesnakes and other pit vipers.

    PubMed

    Tsai, I H; Chen, Y H; Wang, Y M; Tu, M C; Tu, A T

    2001-10-15

    Basic phospholipase A(2) homologs with Lys49 substitution at the essential Ca(2+)-binding site are present in the venom of pit vipers under many genera. However, they have not been found in rattlesnake venoms before. We have now screened for this protein in the venom of rattlesnakes and other less studied pit vipers. By gel filtration chromatography and RP-HPLC, Lys49-phospholipase-like proteins were purified from the venoms of two rattlers, Crotalus atrox and Crotalus m. molossus, and five nonrattlers, Porthidium nummifer, Porthidium godmani, Bothriechis schlegelii, Trimeresurus puniceus, and Trimeresurus albolabris. Their N-terminal amino acid sequences were shown to be characteristic for this phospholipase subfamily. The purified basic proteins from rattlesnakes caused myonecrosis and edema in experimental animals. We have also cloned the cDNAs and solved the complete sequences of four novel Lys49-phospholipases from the venom glands of C. atrox, P. godmani, B. schlegelii, and Deinagkistrodon acutus (hundred-pace). Phylogenetic analyses based on the amino acid sequences of 28 Lys49-phospholipases separate the pitviper of the New World from those of the Old World, and the arboreal Asiatic species from the terrestrial Asiatic species. The implications of the phylogeny tree to the systematics of pit vipers, and structure-function relationship of the Lys49-phospholipases are discussed.

  9. The VIMOS Public Extragalactic Redshift Survey (VIPERS). The coevolution of galaxy morphology and colour to z 1

    NASA Astrophysics Data System (ADS)

    Krywult, J.; Tasca, L. A. M.; Pollo, A.; Vergani, D.; Bolzonella, M.; Davidzon, I.; Iovino, A.; Gargiulo, A.; Haines, C. P.; Scodeggio, M.; Guzzo, L.; Zamorani, G.; Garilli, B.; Granett, B. R.; de la Torre, S.; Abbas, U.; Adami, C.; Bottini, D.; Cappi, A.; Cucciati, O.; Franzetti, P.; Fritz, A.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Polletta, M.; Tojeiro, R.; Zanichelli, A.; Arnouts, S.; Bel, J.; Branchini, E.; Coupon, J.; De Lucia, G.; Ilbert, O.; McCracken, H. J.; Moscardini, L.; Takeuchi, T. T.

    2017-02-01

    Context. The study of the separation of galaxy types into different classes that share the same characteristics, and of the evolution of the specific parameters used in the classification are fundamental for understanding galaxy evolution. Aims: We explore the evolution of the statistical distribution of galaxy morphological properties and colours combining high-quality imaging data from the CFHT Legacy Survey with the large number of redshifts and extended photometry from the VIPERS survey. Methods: Galaxy structural parameters were combined with absolute magnitudes, colours and redshifts in order to trace evolution in a multi-parameter space. Using a new method we analysed the combination of colours and structural parameters of early- and late-type galaxies in luminosity-redshift space. Results: We find that both the rest-frame colour distributions in the (U-B) vs. (B-V) plane and the Sérsic index distributions are well fitted by a sum of two Gaussians, with a remarkable consistency of red-spheroidal and blue-disky galaxy populations, over the explored redshift (0.5 < z < 1) and luminosity (-1.5 < B-B∗ < 1.0) ranges. The combination of the rest-frame colour and Sérsic index as a function of redshift and luminosity allows us to present the structure of both galaxy types and their evolution. We find that early-type galaxies display only a slow change in their concentrations after z = 1. Their high concentrations were already established at z 1 and depend much more strongly on their luminosity than redshift. In contrast, late-type galaxies clearly become more concentrated with cosmic time with only little evolution in colour, which remains dependent mainly on their luminosity. Conclusions: The combination of rest-frame colours and Sérsic index as a function of redshift and luminosity leads to a precise statistical description of the structure of galaxies and their evolution. Additionally, the proposed method provides a robust way to split galaxies into early

  10. African Americans and Glaucoma

    MedlinePlus

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

  11. Black African Traditional Mathematics

    ERIC Educational Resources Information Center

    Zaslavsky, Claudia

    1970-01-01

    Discusses the traditional number systems and the origin of the number names used by several African peoples living south of the Sahara. Also included are limitations in African mathematical development, and possible topics for research. (RP)

  12. Structural and functional characterization of complex formation between two Kunitz-type serine protease inhibitors from Russell's Viper venom.

    PubMed

    Mukherjee, Ashis K; Dutta, Sumita; Kalita, Bhargab; Jha, Deepak K; Deb, Pritam; Mackessy, Stephen P

    2016-01-01

    Snake venom Kunitz-type serine protease inhibitors (KSPIs) exhibit various biological functions including anticoagulant activity. This study elucidates the occurrence and subunit stoichiometry of a putative complex formed between two KSPIs (Rusvikunin and Rusvikunin-II) purified from the native Rusvikunin complex of Pakistan Russell's Viper (Daboia russelii russelii) venom (RVV). The protein components of the Rusvikunin complex were identified by LC-MS/MS analysis. The non-covalent interaction between two major components of the complex (Rusvikunin and Rusvikunin-II) at 1:2 stoichiometric ratio to form a stable complex was demonstrated by biophysical techniques such as spectrofluorometric, classical gel-filtration, equilibrium gel-filtration, circular dichroism (CD), dynamic light scattering (DLS), RP-HPLC and SDS-PAGE analyses. CD measurement showed that interaction between Rusvikunin and Rusvikunin-II did not change their overall secondary structure; however, the protein complex exhibited enhanced hydrodynamic diameter and anticoagulant activity as compared to the individual components of the complex. This study may lay the foundation for understanding the basis of protein complexes in snake venoms and their role in pathophysiology of snakebite.

  13. Occupational injuries with captive lance-headed vipers (Bothrops moojeni): experience from a snake farm in Brazil.

    PubMed

    Nishioka, S A; Silveira, P V; Peixoto-Filho, F M; Jorge, M T; Sandoz, A

    2000-07-01

    We studied occupational injuries with captive lance-headed vipers (Bothrops moojeni) that occurred in a snake farm in south-eastern Brazil from February 1981 to May 1999. The risk of injury, taking into account 13 cases of snake-associated injuries (12 of them snake bites) was 2.73 per 10,000 person-days of work, and 3.51 per 100,000 venom extractions. Thirteen cases of injury occurred in seven workers, whereas 18 workers were never injured, suggesting that some individuals have a higher risk of injury than others perhaps due to lack of concentration or overconfidence. Eight episodes of occupational injuries occurring in four technicians, including a case of eye injury due to splashed venom during extraction, are reported. Assessment of whether envenoming occurred was facilitated by knowledge of the snake species and size, history of recent venom extraction and snake feeding, and examination of snake venom glands. Hypersensitivity reactions (anaphylaxis and serum sickness) to antivenom are a risk particularly to those workers who were bitten more than once and medicated previously. Antivenom therefore should not be administered to these individuals unless there is clear evidence that envenoming occurred or is likely to have occurred. Hypersensitivity to the venom is also a health concern for workers from snake farms.

  14. Bioenergetic modeling reveals that Chinese green tree vipers select postprandial temperatures in laboratory thermal gradients that maximize net energy intake.

    PubMed

    Tsai, Tein-Shun; Lee, How-Jing; Tu, Ming-Chung

    2009-11-01

    With bioenergetic modeling, we tested the hypothesis that reptiles maximize net energy gain by postprandial thermal selection. Previous studies have shown that Chinese green tree vipers (Trimeresurus s. stejnegeri) have postprandial thermophily (mean preferred temperature T(p) for males =27.8 degrees C) in a linear thigmothermal gradient when seclusion sites and water existed. With some published empirical models of digestion associated factors for this snake, we calculated the average rate (E(net)) and efficiency (K(net)) of net energy gain from possible combinations of meal size, activity level, and feeding frequency at each temperature. The simulations consistently revealed that E(net) maximizes at the T(p) of these snakes. Although the K(net) peaks at a lower temperature than E(net), the value of K(net) remains high (>=0.85 in ratio to maximum) at the peak temperature of E(net). This suggested that the demands of both E(net) and K(net) can be attained by postprandial thermal selection in this snake. In conclusion, the data support our prediction that postprandial thermal selection may maximize net energy gain.

  15. Snake venomics of the pit vipers Porthidium nasutum, Porthidium ophryomegas, and Cerrophidion godmani from Costa Rica: toxicological and taxonomical insights.

    PubMed

    Lomonte, Bruno; Rey-Suárez, Paola; Tsai, Wan-Chih; Angulo, Yamileth; Sasa, Mahmood; Gutiérrez, José María; Calvete, Juan J

    2012-02-16

    Within the Neotropical pit vipers, a lineage of primarily Middle American snake species referred to as the "Porthidium group" includes the genera Atropoides, Cerrophidion, and Porthidium. In this study, the venom proteomes of Porthidium nasutum, P. ophryomegas, and Cerrophidion godmani from Costa Rica were analyzed, and correlated to their toxic and enzymatic activities. Their HPLC profiles revealed a higher similarity between the two Porthidium species than between these and C. godmani. Proteins belonging to nine (P. nasutum), eight (P. ophryomegas), and nine (C. godmani) families were identified by mass spectrometry or N-terminal sequencing. Final cataloging of proteins and their relative abundances confirmed the close relationship between venoms of P. nasutum and P. ophryomegas, departing from that of C. godmani. Since the latter species had been taxonomically classified as Porthidium godmani previously, our venomic analyses agree with its current generic status. Venoms of P. nasutum and P. ophryomegas, despite containing abundant metalloproteinases and serine proteinases, lack procoagulant activity on human plasma, in contrast to venom of C. godmani. The latter induced strong myotoxicity in mice, which correlates with its high proportion of phospholipases A(2), whereas venoms from the two Porthidium species, containing lower amounts of these enzymes, induced only mild muscle damage.

  16. The role of prednisolone in reducing limb oedema in children bitten by green pit vipers: a randomized, controlled trial.

    PubMed

    Nuchprayoon, I; Pongpan, C; Sripaiboonkij, N

    2008-10-01

    When green pit vipers (GPV), which are common venomous snakes in Thailand, bite humans they cause coagulopathy as well as local tissue oedema. The use of steroids to reduce such oedema is controversial. The role of low, oral doses of prednisolone in the treatment of GPV bites in children has therefore now been assessed, in a randomized, double-blinded, placebo-controlled, clinical trial in Bangkok. Overall, 43 children aged 3-15 years, each with a recent GPV bite to one limb, were randomly assigned to receive oral prednisolone (1 mg/kg.day) or placebo for 3 days, without antivenom or prophylactic antibiotics. The degree of limb oedema was assessed, immediately before the first dose and then daily, by measuring the limb circumference around the fang marks. By 72 h post-bite, both treatment groups showed significant decreases in the level of their limb oedema. Since, at each time-point, the patients in the two groups showed similar levels of limb oedema (and of reduction in such oedema), there appeared to be no benefit from the use of the prednisolone.

  17. Identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of New World Crotalinae pit vipers.

    PubMed

    Graham, Robert Leslie James; Graham, Ciaren; McClean, Stephen; Chen, Tianbao; O'Rourke, Martin; Hirst, David; Theakston, David; Shaw, Chris

    2005-12-23

    A novel undecapeptide has been isolated and structurally characterized from the venoms of three species of New World pit vipers from the subfamily, Crotalinae. These include the Mexican moccasin (Agkistrodon bilineatus), the prairie rattlesnake (Crotalus viridis viridis), and the South American bushmaster (Lachesis muta). The peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase HPLC. Automated Edman degradation sequencing and MALDI-TOF mass spectrometry established its peptide primary structure as: Thr-Pro-Pro-Ala-Gly-Pro-Asp-Val-Gly-Pro-Arg-OH, with a non-protonated molecular mass of 1063.18 Da. A synthetic replicate of the peptide was found to be an antagonist of bradykinin action at the rat vascular B2 receptor. This is the first bradykinin inhibitory peptide isolated from snake venom. Database searching revealed the peptide to be highly structurally related (10/11 residues) with a domain residing between the bradykinin-potentiating peptide and C-type natriuretic peptide domains of a recently cloned precursor from tropical rattlesnake (Crotalus durissus terrificus) venom gland. BIP thus represents a novel biological entity from snake venom.

  18. Complex longitudinal diversification across South China and Vietnam in Stejneger's pit viper, Viridovipera stejnegeri (Schmidt, 1925) (Reptilia: Serpentes: Viperidae).

    PubMed

    Guo, Peng; Liu, Qin; Zhu, Fei; Zhong, Guang H; Chen, Xin; Myers, Edward A; Che, Jing; Zhang, Liang; Ziegler, Thomas; Nguyen, Truong Q; Burbrink, Frank T

    2016-06-01

    Viridovipera stejnegeri is one of the most common pit vipers in Asia, with a wide distribution in southern China and Vietnam. We investigated historical demography and explored how the environment and climatic factors have shaped genetic diversity and the evolutionary history of this venomous snake. A total of 171 samples from 47 localities were sequenced and analysed for two mitochondrial gene fragments and three nuclear genes. Gene trees reveal the existence of two well-supported clades (Southwest China and Southeast China) with seven distinct and strongly supported, geographically structured subclades within V. stejnegeri. Estimation of divergence time and ancestral area suggests that V. stejnegeri originated at ~6.0 Ma in the late Miocene on the Yunnan-Guizhou Plateau. The estimated date of origin and divergence of the island populations of Taiwan and Hainan closely matches the geological origin of the both islands. The mtDNA gene tree reveals the presence of west-east diversification in V. stejnegeri populations. Complex orogenesis and heterogeneous habitats, as well as climate-mediated habitat differentiation including glacial cycles, all have influenced population structure and the distribution of this taxon. The validity of V. stejnegeri chenbihuii is questionable, and this subspecies most probably represents an invalid taxon.

  19. Multiple causation of phylogeographical pattern as revealed by nested clade analysis of the bamboo viper (Trimeresurus stejnegeri) within Taiwan.

    PubMed

    Creer, S; Malhotra, A; Thorpe, R S; Chou, W H

    2001-08-01

    In order to assess the utility of nested clade analysis, both standard phylogenetic algorithms and nested clade analysis were performed on a geographically widespread survey of mitochondrial DNA haplotypes of the bamboo viper, Trimeresurus stejnegeri, within Taiwan. Gross tree topologies were congruent for all analyses and indicated the presence of two geographically overlapping clades within Taiwan. The smaller lineage was restricted to the north and east coasts, whereas the larger lineage occupied all but the northern range of the species within Taiwan including the Pacific offshore populations of Green and Orchid Islands. The phylogeographical pattern supports the existence of at least one colonization event from the continent since the initial isolation of Taiwan from the mainland in the Pliocene. However, determining the exact number of colonization events was not possible due to the simultaneous vicariant forces of hypothesized continental landbridge connections and the occurrence of dramatic in situ orogenesis throughout the Pleistocene. Nested clade analysis provided multiple temporal and spatial population historical inferences that are not possible with standard analyses and therefore should become widely applied to future phylogeographical studies.

  20. Identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of New World Crotalinae pit vipers

    SciTech Connect

    James Graham, Robert Leslie . E-mail: rl.graham@ulster.ac.uk; Graham, Ciaren; McClean, Stephen; Chen, Tianbao; O'Rourke, Martin; Hirst, David; Theakston, David; Shaw, Chris

    2005-12-23

    A novel undecapeptide has been isolated and structurally characterized from the venoms of three species of New World pit vipers from the subfamily, Crotalinae. These include the Mexican moccasin (Agkistrodon bilineatus), the prairie rattlesnake (Crotalus viridis viridis), and the South American bushmaster (Lachesis muta). The peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase HPLC. Automated Edman degradation sequencing and MALDI-TOF mass spectrometry established its peptide primary structure as: Thr-Pro-Pro-Ala-Gly-Pro-Asp-Val-Gly-Pro-Arg-OH, with a non-protonated molecular mass of 1063.18 Da. A synthetic replicate of the peptide was found to be an antagonist of bradykinin action at the rat vascular B2 receptor. This is the first bradykinin inhibitory peptide isolated from snake venom. Database searching revealed the peptide to be highly structurally related (10/11 residues) with a domain residing between the bradykinin-potentiating peptide and C-type natriuretic peptide domains of a recently cloned precursor from tropical rattlesnake (Crotalus durissus terrificus) venom gland. BIP thus represents a novel biological entity from snake venom.

  1. The African Connection

    ERIC Educational Resources Information Center

    Oguntoyinbo, Lekan

    2012-01-01

    From student and faculty exchanges to joint research projects, U.S. universities maintain a broad spectrum of collaborative relationships with African universities. It's unclear how many U.S. colleges and universities have partnerships with African universities. The African Studies Association, an organization of scholars, doesn't keep that kind…

  2. Reproductive cycle of free-living male Saharan sand vipers, Cerastes vipera (Viperidae) in the Negev desert, Israel.

    PubMed

    Sivan, Jaim; Kam, Michael; Hadad, Shlomo; Allan Degen, A; Rozenboim, Israel; Rosenstrauch, Avi

    2012-11-01

    The Saharan sand viper, Cerastes vipera (Linnaeus, 1758), is distributed in all Saharan countries, being confined to sand and dune systems. This relatively small snake, up to 35 cm, is nocturnal, is active from spring to autumn (April to October) and hibernates during the winter (November to March). We predicted that C. vipera would have peak plasma testosterone concentration at mating and that the vas deferens would contain abundant spermatozoa at that time. To test our predictions, we collected information on the time of mating and measured monthly testosterone concentration, testes size and testicular activity in free-living male C. vipera during its active period from April to October. Mating occurred only during spring. The pattern of plasma testosterone concentration, testes volume, seminiferous tubule diameter and spermatogenesis all followed the general pattern of high values in autumn and spring and low values in early summer. Our predictions were partially supported. There was a high plasma testosterone concentration at mating in spring and the vas deferens contained abundant spermatozoa, as predicted, but there was also a high plasma testosterone concentration in autumn without mating. We concluded that: (1) males are both aestival in that they produce spermatozoa in autumn, which they store over the winter hibernation period, and vernal in that they produce spermatozoa in spring prior to mating; (2) matings are associated with spermatogenesis; and (3) the high plasma testosterone concentration is concomitant with both matings and spermatogenesis in spring and with spermatogenesis in autumn. We propose that C. vipera has a single peak of testicular activity and plasma testosterone concentration which start in autumn and end in spring. We also propose that spermatogenesis is prior to spring mating and, consequently, is prenuptial.

  3. Structural and evolutionary insights into endogenous alpha-phospholipase A2 inhibitors of Latin American pit vipers.

    PubMed

    Estevão-Costa, Maria Inácia; Fernandes, Carlos Alexandre H; Mudadu, Maurício de Alvarenga; Franco, Glória Regina; Fontes, Marcos Roberto M; Fortes-Dias, Consuelo Latorre

    2016-03-15

    Phospholipases A2 are major components of snake venoms (svPLA2s) and are able to induce multiple local and systemic deleterious effects upon envenomation. Several snake species are provided with svPLA2 inhibitors (sbPLIs) in their circulating blood, which confer a natural resistance against the toxic components of homologous and heterologous venoms. The sbPLIs belong to any of three structural classes named α, β and γ. In the present study, we identified, characterized and performed structural and evolutionary analyses of sbαPLIs transcripts and the encoded proteins, in the most common Latin American pit vipers belonging to Crotalus, Bothrops and Lachesis genera. Mutation data indicated that sbαPLIs from Latin American snakes might have evolved in an accelerated manner, similarly to that reported for sbαPLIs from Asian snakes, and possibly co-evoluted with svPLA2s in response to the diversity of target enzymes. The importance of sbαPLI trimerization for the effective binding and inhibition of acidic svPLA2s is discussed and conserved cationic residues located at the central pore of the inhibitor trimer are suggested to be a significant part of the binding site of sbαPLIs to acidic svPLA2s. Our data contribute to the current body of knowledge on the structural and evolutionary characteristics of sbPLIs, in general, and may assist in the future development of selective inhibitors for secretory PLA2 from several sources.

  4. The galaxy-halo connection from a joint lensing, clustering and abundance analysis in the CFHTLenS/VIPERS field

    NASA Astrophysics Data System (ADS)

    Coupon, J.; Arnouts, S.; van Waerbeke, L.; Moutard, T.; Ilbert, O.; van Uitert, E.; Erben, T.; Garilli, B.; Guzzo, L.; Heymans, C.; Hildebrandt, H.; Hoekstra, H.; Kilbinger, M.; Kitching, T.; Mellier, Y.; Miller, L.; Scodeggio, M.; Bonnett, C.; Branchini, E.; Davidzon, I.; De Lucia, G.; Fritz, A.; Fu, L.; Hudelot, P.; Hudson, M. J.; Kuijken, K.; Leauthaud, A.; Le Fèvre, O.; McCracken, H. J.; Moscardini, L.; Rowe, B. T. P.; Schrabback, T.; Semboloni, E.; Velander, M.

    2015-05-01

    We present new constraints on the relationship between galaxies and their host dark matter haloes, measured from the location of the peak of the stellar-to-halo mass ratio (SHMR), up to the most massive galaxy clusters at redshift z ˜ 0.8 and over a volume of nearly 0.1 Gpc3. We use a unique combination of deep observations in the CFHTLenS/VIPERS field from the near-UV to the near-IR, supplemented by ˜60 000 secure spectroscopic redshifts, analysing galaxy clustering, galaxy-galaxy lensing and the stellar mass function. We interpret our measurements within the halo occupation distribution (HOD) framework, separating the contributions from central and satellite galaxies. We find that the SHMR for the central galaxies peaks at M_{h, peak} = 1.9^{+0.2}_{-0.1}× 10^{12} M_{⊙} with an amplitude of 0.025, which decreases to ˜0.001 for massive haloes ({{{M}_h}}> 10^{14} M_{⊙}). Compared to central galaxies only, the total SHMR (including satellites) is boosted by a factor of 10 in the high-mass regime (cluster-size haloes), a result consistent with cluster analyses from the literature based on fully independent methods. After properly accounting for differences in modelling, we have compared our results with a large number of results from the literature up to z = 1: we find good general agreement, independently of the method used, within the typical stellar-mass systematic errors at low to intermediate mass (M_{star}<10^{11} M_{⊙}) and the statistical errors above. We have also compared our SHMR results to semi-analytic simulations and found that the SHMR is tilted compared to our measurements in such a way that they over- (under-) predict star formation efficiency in central (satellite) galaxies.

  5. Arboreal green pit vipers (genus Trimeresurus) of South-East Asia: bites by T. albolabris and T. macrops in Thailand and a review of the literature.

    PubMed

    Hutton, R A; Looareesuwan, S; Ho, M; Silamut, K; Chanthavanich, P; Karbwang, J; Supanaranond, W; Vejcho, S; Viravan, C; Phillips, R E

    1990-01-01

    In Thailand 29 patients were proved to have been bitten by arboreal green pit vipers: 24 by Trimeresurus albolabris and 5 by T. macrops. They were studied in order to define the clinical effects of envenoming, to characterize the haemostatic abnormalities and assess the efficacy of Thai Red Cross antivenom. T. macrops caused only local painful swelling, neutrophil leucocytosis and thrombocytopenia. T. albolabris caused more severe envenoming with local blistering and necrosis, shock, spontaneous systemic bleeding, defibrination, thrombocytopenia and leucocytosis. There was no evidence of disseminated intravascular coagulation, but fibrinolytic activity was increased. Platelet function was normal. The product of admission venom antigen concentration and the delay between bite and admission was significantly higher in defibrinated patients than in those without severe coagulopathy. Antivenom (5 ampoules intravenously) restored blood coagulability, but there was persistent venom antigenaemia, associated in some cases with recurrent coagulopathy. The literature on bites by south Asian green pit vipers of the genus Trimeresurus is reviewed; these bites are common medical problems and causes of morbidity. The identification of individual species is difficult, but may be important if antivenom is to be improved and used appropriately.

  6. In Vitro and In Vivo Evaluation of Polyherbal Formulation against Russell's Viper and Cobra Venom and Screening of Bioactive Components by Docking Studies

    PubMed Central

    Sakthivel, G.; Dey, Amitabha; Nongalleima, Kh.; Chavali, Murthy; Rimal Isaac, R. S.; Singh, N. Surjit; Deb, Lokesh

    2013-01-01

    The present study emphasizes to reveal the antivenom activity of Aristolochia bracteolata Lam., Tylophora indica (Burm.f.) Merrill, and Leucas aspera S. which were evaluated against venoms of Daboia russelli russelli (Russell's viper) and Naja naja (Indian cobra). The aqueous extracts of leaves and roots of the above-mentioned plants and their polyherbal (1 : 1 : 1) formulation at a dose of 200 mg/kg showed protection against envenomed mice with LD50 doses of 0.44 mg/kg and 0.28 mg/kg against Russell's viper and cobra venom, respectively. In in vitro antioxidant activities sample extracts showed free radical scavenging effects in dose dependent manner. Computational drug design and docking studies were carried out to predict the neutralizing principles of type I phospholipase A2 (PLA2) from Indian common krait venom. This confirmed that aristolochic acid and leucasin can neutralize type I PLA2 enzyme. Results suggest that these plants could serve as a source of natural antioxidants and common antidote for snake bite. However, further studies are needed to identify the lead molecule responsible for antidote activity. PMID:23533518

  7. Nuclear markers support the mitochondrial phylogeny of Vipera ursinii-renardi complex (Squamata: Viperidae) and species status for the Greek meadow viper.

    PubMed

    Mizsei, Edvárd; Jablonski, Daniel; Roussos, Stephanos A; Dimaki, Maria; Ioannidis, Yannis; Nilson, Göran; Nagy, Zoltán T

    2017-01-31

    Meadow vipers (Vipera ursinii-renardi complex) are small-bodied snakes that live in either lowland grasslands or montane subalpine-alpine meadows spanning a distribution from France to western China. This complex has previously been the focus of several taxonomic studies which were based mainly on morphological, allozyme or immunological characters and did not clearly resolve the relationships between the various taxa. Recent mitochondrial DNA analyses found unexpected relationships within the complex which had taxonomical consequences for the detected lineages. The most surprising was the basal phylogenetic position of Vipera ursinii graeca, a taxon described almost 30 years ago from the mountains of Greece. We present here new analyses of three nuclear markers (BDNF, NT3, PRLR; a first for studies of meadow and steppe vipers) as well as analyses of newly obtained mitochondrial DNA sequences (CYT B, ND4).Our Bayesian analyses of nuclear sequences are concordant with previous studies of mitochondrial DNA, in that the phylogenetic position of the graeca clade is a clearly distinguished and distinct lineage separated from all other taxa in the complex. These phylogenetic results are also supported by a distinct morphology, ecology and isolated distribution of this unique taxon. Based on several data sets and an integrative species concept we recommend to elevate this taxon to species level: Vipera graeca Nilson & Andrén, 1988 stat. nov.

  8. The African superswell

    NASA Technical Reports Server (NTRS)

    Nyblade, Andrew A.; Robinson, Scott W.

    1994-01-01

    Maps of residual bathymetry in the ocean basins around the African continent reveal a broad bathymetric swell in the southeastern Atlantic Ocean with an amplitude of about 500 m. We propose that this region of anomalously shallow bathymetry, together with the contiguous eastern and southern African plateaus, form a superswell which we refer to as the African superswell. The origin of the African superswell is uncertain. However, rifting and volcanism in eastern Africa, as well as heat flow measurements in southern Africa and the southeastern Atlantic Ocean, suggest that the superswell may be attributed, at least in part, to heating of the lithosphere.

  9. The VIMOS Public Extragalactic Redshift Survey (VIPERS). An unprecedented view of galaxies and large-scale structure at 0.5 < z < 1.2

    NASA Astrophysics Data System (ADS)

    Guzzo, L.; Scodeggio, M.; Garilli, B.; Granett, B. R.; Fritz, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Hudelot, P.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Peacock, J. A.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zamorani, G.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-06-01

    We describe the construction and general features of VIPERS, the VIMOS Public Extragalactic Redshift Survey. This ESO Large Programme is using the Very Large Telescope with the aim of building a spectroscopic sample of ~ 100 000 galaxies with iAB< 22.5 and 0.5 VIPERS is designed to address a broad range of problems in large-scale structure and galaxy evolution, thanks to a unique combination of volume (~ 5 × 107h-3 Mpc3) and sampling rate (~ 40%), comparable to state-of-the-art surveys of the local Universe, together with extensive multi-band optical and near-infrared photometry. Here we present the survey design, the selection of the source catalogue and the development of the spectroscopic observations. We discuss in detail the overall selection function that results from the combination of the different constituents of the project. This includes the masks arising from the parent photometric sample and the spectroscopic instrumental footprint, together with the weights needed to account for the sampling and the success rates of the observations. Using the catalogue of 53 608 galaxy redshifts composing the forthcoming VIPERS Public Data Release 1 (PDR-1), we provide a first assessment of the quality of the spectroscopic data. The stellar contamination is found to be only 3.2%, endorsing the quality of the star-galaxy separation process and fully confirming the original estimates based on the VVDS data, which also indicate a galaxy incompleteness from this process of only 1.4%. Using a set of 1215 repeated observations, we estimate an rms redshift error σz/ (1 + z) = 4.7 × 10-4 and calibrate the internal spectral quality grading. Benefiting from the combination of size and detailed sampling of this dataset, we conclude by presenting a map showing in unprecedented detail the large-scale distribution of galaxies between 5 and 8 billion years ago. Based on observations

  10. Understanding African American Males

    ERIC Educational Resources Information Center

    Bell, Edward Earl

    2010-01-01

    The purpose of this study was to assess the socialization skills, self-esteem, and academic readiness of African American males in a school environment. Discussions with students and the School Perceptions Questionnaire provided data for this investigation. The intended targets for this investigation were African American students; however, there…

  11. Africans Away from Home.

    ERIC Educational Resources Information Center

    Clarke, John Henrik

    Africans who were brought across the Atlantic as slaves never fully adjusted to slavery or accepted its inevitability. Resistance began on board the slave ships, where many jumped overboard or committed suicide. African slaves in South America led the first revolts against tyranny in the New World. The first slave revolt in the Caribbean occurred…

  12. Educating African American Males

    ERIC Educational Resources Information Center

    Bell, Edward E.

    2010-01-01

    Background: Schools across America spend money, invest in programs, and sponsor workshops, offer teacher incentives, raise accountability standards, and even evoke the name of Obama in efforts to raise the academic achievement of African American males. Incarceration and college retention rates point to a dismal plight for many African American…

  13. 16 Extraordinary African Americans.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    This collection for children tells the stories of 16 African Americans who helped make America what it is today. African Americans can take pride in the heritage of these contributors to society. Biographies are given for the following: (1) Sojourner Truth, preacher and abolitionist; (2) Frederick Douglass, abolitionist; (3) Harriet Tubman, leader…

  14. Keeping African Masks Real

    ERIC Educational Resources Information Center

    Waddington, Susan

    2012-01-01

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

  15. The VIPERS Multi-Lambda Survey. II. Diving with massive galaxies in 22 square degrees since z = 1.5

    NASA Astrophysics Data System (ADS)

    Moutard, T.; Arnouts, S.; Ilbert, O.; Coupon, J.; Davidzon, I.; Guzzo, L.; Hudelot, P.; McCracken, H. J.; Van Werbaeke, L.; Morrison, G. E.; Le Fèvre, O.; Comte, V.; Bolzonella, M.; Fritz, A.; Garilli, B.; Scodeggio, M.

    2016-05-01

    We investigate the evolution of the galaxy stellar mass function and stellar mass density from redshift z = 0.2 to z = 1.5 of a Ks < 22-selected sample with highly reliable photometric redshifts and over an unprecedentedly large area. Our study is based on near-infrared observations carried out with the WIRCam instrument at CFHT over the footprint of the VIPERS spectroscopic survey and benefits from the high-quality optical photometry from the CFHTLS and ultraviolet observations with the GALEX satellite. The accuracy of our photometric redshifts is σΔz/ (1 + z) < 0.03 and 0.05 for the bright (iAB< 22.5) and faint (iAB > 22.5) samples, respectively. The galaxy stellar mass function is measured with ~760 000 galaxies down to Ks ~ 22 and over an effective area of ~22.4 deg2, the latter of which drastically reduces the statistical uncertainties (i.e. Poissonian error and cosmic variance). We point out the importance of carefully controlling the photometric calibration, whose effect becomes quickly dominant when statistical uncertainties are reduced, which will be a major issue for future cosmological surveys with EUCLID or LSST, for instance. By exploring the rest-frame (NUV-r) vs. (r-Ks) colour-colour diagram with which we separated star-forming and quiescent galaxies, (1) we find that the density of very massive log (M∗/M⊙) > 11.5 galaxies is largely dominated by quiescent galaxies and increases by a factor 2 from z ~ 1 to z ~ 0.2, which allows for additional mass assembly through dry mergers. (2) We also confirm the scenario in which star formation activity is impeded above a stellar mass log(ℳ*SF/M⊙) = 10.64±0.01. This value is found to be very stable at 0.2

  16. Neotropical Africanized honey bees have African mitochondrial DNA.

    PubMed

    Smith, D R; Taylor, O R; Brown, W M

    1989-05-18

    Non-indigenous African honey bees have invaded most of South and Central America in just over 30 years. The genetic composition of this population and the means by which it rapidly colonizes new territory remain controversial. In particular, it has been unclear whether this 'Africanized' population has resulted from interbreeding between African and domestic European bees, or is an essentially pure African population. Also, it has not been known whether this population expanded primarily by female or by male migration. Restriction site mapping of 62 mitochondrial DNAs of African bees from Brazil, Venezuela and Mexico reveals that 97% were of African (Apis mellifera scutellata) type. Although neotropical European apiary populations are rapidly Africanized by mating with neotropical African males, there is little reciprocal gene flow to the neotropical African population through European females. These are the first genetic data to indicate that the neotropical African population could be expanding its range by female migration.

  17. Hypopituitarism following envenoming by Russell's vipers (Daboia siamensis and D. russelii) resembling Sheehan's syndrome: first case report from Sri Lanka, a review of the literature and recommendations for endocrine management.

    PubMed

    Antonypillai, C N; Wass, J A H; Warrell, D A; Rajaratnam, H N

    2011-02-01

    Russell's vipers (Daboia russelii and D. siamensis) inhabit 10 South and South East Asian countries. People envenomed by these snakes suffer coagulopathy, bleeding, shock, neurotoxicity, acute kidney injury and local tissue damage leading to severe morbidity and mortality. An unusual complication of Russell's viper bite envenoming in Burma (D. siamensis) and southern India (D. russelii) is hypopituitarism but until now it has not been reported elsewhere. Here, we describe the first case of hypopituitarism following Russell's viper bite in Sri Lanka, review the literature on this subject and make recommendations for endocrine investigation and management. A 49-year-old man was bitten and seriously envenomed by D. russelii in 2005. He was treated with antivenom but although he recovered from the acute effects he remained feeling unwell. Hypopituitarism, with deficiencies of gonadal, steroid and thyroid axes, was diagnosed 3 years later. He showed marked improvement after replacement of anterior pituitary hormones. We attribute his hypopituitarism to D. russelii envenoming. Russell's viper bite is known to cause acute and chronic hypopituitarism and diabetes insipidus, perhaps through deposition of fibrin microthrombi and haemorrhage in the pituitary gland resulting from the action of venom procoagulant enzymes and haemorrhagins. Forty nine cases of hypopituitarism following Russell's viper bite have been described in the English language literature. Patients with acute hypopituitarism may present with hypoglycaemia and hypotension during the acute phase of envenoming. Those with chronic hypopituitarism seem to have recovered from envenoming but present later with features of hypopituitarism. Over 85% of these patients had suffered acute kidney injury immediately after the bite. Steroid replacement in acute hypopituitarism is life saving. All 11 patients with chronic hypopituitarism in whom the outcome of treatment was reported, showed marked improvement with hormone

  18. The VIMOS Public Extragalactic Redshift Survey (VIPERS) . Luminosity and stellar mass dependence of galaxy clustering at 0.5 < z < 1.1

    NASA Astrophysics Data System (ADS)

    Marulli, F.; Bolzonella, M.; Branchini, E.; Davidzon, I.; de la Torre, S.; Granett, B. R.; Guzzo, L.; Iovino, A.; Moscardini, L.; Pollo, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Cappi, A.; Coupon, J.; Cucciati, O.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; McCracken, H. J.; Paioro, L.; Polletta, M.; Schlagenhaufer, H.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.; Zamorani, G.

    2013-09-01

    Aims: We investigate the dependence of galaxy clustering on luminosity and stellar mass in the redshift range 0.5 < z < 1.1, using the first ~ 55 000 redshifts from the VIMOS Public Extragalactic Redshift Survey (VIPERS). Methods: We measured the redshift-space two-point correlation functions (2PCF), ξ(s) and ξ(rp,π) , and the projected correlation function, wp(rp), in samples covering different ranges of B-band absolute magnitudes and stellar masses. We considered both threshold and binned galaxy samples, with median B-band absolute magnitudes - 21.6 ≲ MB - 5log (h) ≲ - 19.5 and median stellar masses 9.8 ≲ log (M⋆ [h-2 M⊙]) ≲ 10.7. We assessed the real-space clustering in the data from the projected correlation function, which we model as a power law in the range 0.2 < rp [h-1 Mpc ] < 20. Finally, we estimated the galaxy bias as a function of luminosity, stellar mass, and redshift, assuming a flat Λ cold dark matter model to derive the dark matter 2PCF. Results: We provide the best-fit parameters of the power-law model assumed for the real-space 2PCF - the correlation length, r0, and the slope, γ - as well as the linear bias parameter, as a function of the B-band absolute magnitude, stellar mass, and redshift. We confirm and provide the tightest constraints on the dependence of clustering on luminosity at 0.5 < z < 1.1. We prove the complexity of comparing the clustering dependence on stellar mass from samples that are originally flux-limited and discuss the possible origin of the observed discrepancies. Overall, our measurements provide stronger constraints on galaxy formation models, which are now required to match, in addition to local observations, the clustering evolution measured by VIPERS galaxies between z = 0.5 and z = 1.1 for a broad range of luminosities and stellar masses. Based on observations collected at the European Southern Observatory, Paranal, Chile, under programmes 182.A-0886 (LP) at the Very Large Telescope, and also based on

  19. Discovery of toxin-encoding genes from the false viper Macropisthodon rudis, a rear-fanged snake, by transcriptome analysis of venom gland.

    PubMed

    Zhang, Zhixiao; Zhang, Xi; Hu, Tingsong; Zhou, Weiguo; Cui, Qinghua; Tian, Jing; Zheng, Ying; Fan, Quanshui

    2015-11-01

    Although rear-fanged snakes are often considered as non-threatening to humans, some species are lethal or medically hazardous. The toxin components and bioactivities of front-fanged snakes have been extensively studied; however, only limited research has explored the venoms of rear-fanged snakes. The false viper, Macropisthodon rudis, is widespread in southern China, but little is known about the toxins that this snake produces. Here, we analyzed the transcriptome of the venom gland of M. rudis using high-throughput sequencing with an illumina HiSeq 2000. The raw data were assembled and annotated using public databases. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology (GO) were analyzed. Using sequence comparisons, snake venom metalloproteinases (SVMPs) and a phosphodiesterase (PDE) were discovered in the venom gland of M. rudis.

  20. African American Suicide

    MedlinePlus

    ... accounted for 83.8% of Caucasian elderly suicides. • Firearms were the predominant method of suicide among African ... per 100,000 annually. Source: Centers for Disease Control and Prevention. National Vital Statistics System. Mortality Data. ...

  1. Obesity and African Americans

    MedlinePlus

    ... and Management System Report to Congress Knowledge Center Capacity Building Information Services Events Calendar Resource Guide Justice ... Workforce Diversity Grants Youth Program Grants Other Grants Planning and Evaluation Grantee Best Practices Black/African American ...

  2. Visual PEF Reader - VIPER

    NASA Technical Reports Server (NTRS)

    Luo, Victor; Khanampornpan, Teerapat; Boehmer, Rudy A.; Kim, Rachel Y.

    2011-01-01

    This software graphically displays all pertinent information from a Predicted Events File (PEF) using the Java Swing framework, which allows for multi-platform support. The PEF is hard to weed through when looking for specific information and it is a desire for the MRO (Mars Reconn aissance Orbiter) Mission Planning & Sequencing Team (MPST) to have a different way to visualize the data. This tool will provide the team with a visual way of reviewing and error-checking the sequence product. The front end of the tool contains much of the aesthetically appealing material for viewing. The time stamp is displayed in the top left corner, and highlighted details are displayed in the bottom left corner. The time bar stretches along the top of the window, and the rest of the space is allotted for blocks and step functions. A preferences window is used to control the layout of the sections along with the ability to choose color and size of the blocks. Double-clicking on a block will show information contained within the block. Zooming into a certain level will graphically display that information as an overlay on the block itself. Other functions include using hotkeys to navigate, an option to jump to a specific time, enabling a vertical line, and double-clicking to zoom in/out. The back end involves a configuration file that allows a more experienced user to pre-define the structure of a block, a single event, or a step function. The individual will have to determine what information is important within each block and what actually defines the beginning and end of a block. This gives the user much more flexibility in terms of what the tool is searching for. In addition to the configurability, all the settings in the preferences window are saved in the configuration file as well

  3. Viper Plague Project

    DTIC Science & Technology

    2009-07-01

    as a diagnostic tool against rickettsial diseases by cross-reacting, through Weil-Felix reactions, with Spotted- Fever Group and Typhus Group...reactivity with the rickettsiae, namely the Spotted Fever Group and the Typhus Group rickettsiae. 10.2 Preliminary Testing Testing was...antigen of spotted fever and typhus class rickettsia were engineered that exhibited specific binding for the model target microbe that shares the

  4. Design project: Viper

    NASA Technical Reports Server (NTRS)

    Haithcock, Stephen; Koncak, Kyle; Neufang, Rich; Paufler, David; Snow, Russ; Wlad, Frank

    1992-01-01

    The design specification of the primary flight trainer are: must conform to F.A.R. 23, including the crashworthiness standards; is limited to two to four occupants; engine must be FAA certified; must comply with FAA standards for VFR and allow for upgrade to IFR flights; must be at least utility category with good spin recovery characteristics; must have a structural lifetime of at least 10,000 flight hours; capable of either of two training missions: climb to 5,000 ft., cruise 500 Nm. plus reserve, land, or climb to 1,000 ft. and descend ten cycles for landing practice, climb to 3,000 ft., maneuver at two g's for 15 minutes, cruise 100 Nm. and land; must have a cruise speed of at least 120 knots; must take-off or land on a runway no longer than 3,000 ft; and has a cost goal of $50,000, not including avionics, for production of 1,000 airplanes over a five year period.

  5. Coccidioidomycosis in African Americans

    PubMed Central

    Ruddy, Barbara E.; Mayer, Anita P.; Ko, Marcia G.; Labonte, Helene R.; Borovansky, Jill A.; Boroff, Erika S.; Blair, Janis E.

    2011-01-01

    Coccidioidomycosis is caused by Coccidioides species, a fungus endemic to the desert regions of the southwestern United States, and is of particular concern for African Americans. We performed a PubMed search of the English-language medical literature on coccidioidomycosis in African Americans and summarized the pertinent literature. Search terms were coccidioidomycosis, Coccidioides, race, ethnicity, African, black, and Negro. The proceedings of the national and international coccidioidomycosis symposia were searched. All relevant articles and their cited references were reviewed; those with epidemiological, immunologic, clinical, and therapeutic data pertaining to coccidioidomycosis in African Americans were included in the review. Numerous studies documented an increased predilection for severe coccidioidal infections, coccidioidomycosis-related hospitalizations, and extrapulmonary dissemination in persons of African descent; however, most of the published studies are variably problematic. The immunologic mechanism for this predilection is unclear. The clinical features and treatment recommendations are summarized. Medical practitioners need to be alert to the possibility of coccidioidomycosis in persons with recent travel to or residence in an area where the disease is endemic. PMID:21193657

  6. Mental Health and African Americans

    MedlinePlus

    ... Minority Population Profiles > Black/African American > Mental Health Mental Health and African Americans Poverty level affects mental health ... compared to 120% of non-Hispanic whites. 1 MENTAL HEALTH STATUS Serious psychological distress among adults 18 years ...

  7. The Struggles over African Languages

    ERIC Educational Resources Information Center

    Maseko, Pam; Vale, Peter

    2016-01-01

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

  8. Narcolepsy in African Americans

    PubMed Central

    Kawai, Makoto; O'Hara, Ruth; Einen, Mali; Lin, Ling; Mignot, Emmanuel

    2015-01-01

    Study Objectives: Although narcolepsy affects 0.02–0.05% of individuals in various ethnic groups, clinical presentation in different ethnicities has never been fully characterized. Our goal was to study phenotypic expression across ethnicities in the United States. Design/Setting: Cases of narcolepsy from 1992 to 2013 were identified from searches of the Stanford Center for Narcolepsy Research database. International Classification of Sleep Disorders, Third Edition diagnosis criteria for type 1 and type 2 narcolepsy were used for inclusion, but subjects were separated as with and without cataplexy for the purpose of data presentation. Information extracted included demographics, ethnicity and clinical data, HLA-DQB1*06:02, polysomnography (PSG), multiple sleep latency test (MSLT) data, and cerebrospinal fluid (CSF) hypocretin-1 level. Patients: 182 African-Americans, 839 Caucasians, 35 Asians, and 41 Latinos with narcolepsy. Results: Sex ratio, PSG, and MSLT findings did not differ across ethnicities. Epworth Sleepiness Scale (ESS) score was higher and age of onset of sleepiness earlier in African Americans compared with other ethnicities. HLA-DQB1*06:02 positivity was higher in African Americans (91.0%) versus others (76.6% in Caucasians, 80.0% in Asians, and 65.0% in Latinos). CSF hypocretin-1 level, obtained in 222 patients, was more frequently low (≤ 110 pg/ml) in African Americans (93.9%) versus Caucasians (61.5%), Asians (85.7%) and Latinos (75.0%). In subjects with low CSF hypocretin-1, African Americans (28.3%) were 4.5 fold more likely to be without cataplexy when compared with Caucasians (8.1%). Conclusions: Narcolepsy in African Americans is characterized by earlier symptom onset, higher Epworth Sleepiness Scale score, higher HLA-DQB1*06:02 positivity, and low cerebrospinal fluid hypocretin-1 level in the absence of cataplexy. In African Americans, more subjects without cataplexy have type 1 narcolepsy. Citation: Kawai M, O'Hara R, Einen M, Lin L

  9. The VIMOS Public Extragalactic Redshift Survey (VIPERS):. A quiescent formation of massive red-sequence galaxies over the past 9 Gyr

    NASA Astrophysics Data System (ADS)

    Fritz, A.; Scodeggio, M.; Ilbert, O.; Bolzonella, M.; Davidzon, I.; Coupon, J.; Garilli, B.; Guzzo, L.; Zamorani, G.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Cucciati, O.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Granett, B. R.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-03-01

    We explore the evolution of the colour-magnitude relation (CMR) and luminosity function (LF) at 0.4 < z < 1.3 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) using ~45 000 galaxies with precise spectroscopic redshifts down to i'AB < 22.5 over ~10.32 deg2 in two fields. From z = 0.5 to z = 1.3 the LF and CMR are well defined for different galaxy populations and M*B evolves by ~1.04(1.09) ± 0.06(0.10) mag for the total (red) galaxy sample. We compare different criteria for selecting early-type galaxies: (1) a fixed cut in rest-frame (U - V) colours, (2) an evolving cut in (U - V) colours, (3) a rest-frame (NUV - r') - (r' - K) colour selection, and (4) a spectral-energy-distribution classification. The completeness and contamination varies for the different methods and with redshift, but regardless of the method we measure a consistent evolution of the red-sequence (RS). Between 0.4 < z < 1.3 we find a moderate evolution of the RS intercept of Δ(U - V) = 0.28 ± 0.14 mag, favouring exponentially declining star formation (SF) histories with SF truncation at 1.7 ≤ z ≤ 2.3. Together with the rise in the number density of red galaxies by 0.64 dex since z = 1, this suggests a rapid build-up of massive galaxies (M⋆ > 1011 M⊙) and expeditious RS formation over a short period of ~1.5 Gyr starting before z = 1. This is supported by the detection of ongoing SF in early-type galaxies at 0.9 < z < 1.0, in contrast with the quiescent red stellar populations of early-type galaxies at 0.5 < z < 0.6. There is an increase in the observed CMR scatter with redshift, which is two times larger than observed in galaxy clusters and at variance with theoretical model predictions. We discuss possible physical mechanisms that support the observed evolution of the red galaxy population. Our findings point out that massive galaxies have experienced a sharp SF quenching at z ~ 1 with only limited additional merging. In contrast, less-massive galaxies experience a mix of SF

  10. The genetic structure and history of Africans and African Americans.

    PubMed

    Tishkoff, Sarah A; Reed, Floyd A; Friedlaender, Françoise R; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B; Awomoyi, Agnes A; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T; Kotze, Maritha J; Lema, Godfrey; Moore, Jason H; Mortensen, Holly; Nyambo, Thomas B; Omar, Sabah A; Powell, Kweli; Pretorius, Gideon S; Smith, Michael W; Thera, Mahamadou A; Wambebe, Charles; Weber, James L; Williams, Scott M

    2009-05-22

    Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (approximately 71%), European (approximately 13%), and other African (approximately 8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies.

  11. Elective: African Literature.

    ERIC Educational Resources Information Center

    Jenkins, Kenneth V.

    The make-up of a course in African literature for high school students is discussed. It is pointed out that the course can be constructed on already familiar lines. High school students will be able to describe clearly, for example, the relationship between environment and character or the dilemma of characters caught between traditional values…

  12. African Americans and Agriculture.

    ERIC Educational Resources Information Center

    Morgan, Joan

    2000-01-01

    Reviews the opportunities available in the field of agriculture for African American students and notes efforts of the 136 colleges of agriculture to publicize their offerings and recruit students. Profiles six black leaders in agriculture, highlighting their achievements in research and aid to developing countries. A table provides data on annual…

  13. African Literature: Selected Resources.

    ERIC Educational Resources Information Center

    Deschenes, Martin O.; Waters, Harold A.

    This bibliography of resources for the teaching of African literature includes over 100 citations of books, textbooks, anthologies, plays, novels, short stories, and periodicals in French and English. Publishing house addresses, audiovisual aids, professional organizations, and a course list are also cited. The books are listed under the following…

  14. Mitochondrial phylogeny shows multiple independent ecological transitions and northern dispersion despite of Pleistocene glaciations in meadow and steppe vipers (Vipera ursinii and Vipera renardi).

    PubMed

    Zinenko, Oleksandr; Stümpel, Nikolaus; Mazanaeva, Lyudmila; Bakiev, Andrey; Shiryaev, Konstantin; Pavlov, Aleksey; Kotenko, Tatiana; Kukushkin, Oleg; Chikin, Yury; Duisebayeva, Tatiana; Nilson, Göran; Orlov, Nikolai L; Tuniyev, Sako; Ananjeva, Natalia B; Murphy, Robert W; Joger, Ulrich

    2015-03-01

    The phylogeny and historical demography of small Eurasian vipers of the Vipera ursinii and V. renardi complexes were studied using mitochondrial DNA sequences analysed with Bayesian inference, Maximum Likelihood and Maximum Parsimony approaches, and mismatch distributions. Diversification in the group resulted from an initial dispersion in the later Pliocene - Pleistocene in two directions: north-westwards via the Balkans (V. ursinii complex) and north-eastwards from Asia Minor via the Caucasus (V. renardi complex). An independent, comparatively recent transition occurred from montane habitats to lowland grasslands in different mitochondrial lineages during the Late Pleistocene, when representatives of the both complexes had reached lowland steppes to the north. Effective population size showed clear signs of rapid growth in eastern V. renardi, triggered by colonization of vast lowland steppes, but in western V. ursinii complex grew during the Last Glaciation and experienced stabilization in Holocene. Expansion and population growth in lowland lineages of V. renardi was not strongly affected by Pleistocene climatic oscillations, when cold, dry conditions could have favoured species living in open grasslands. The high diversity of closely related haplotypes in the Caucasus and Tien-Shan could have resulted from repetitive expansion-constriction-isolation events in montane regions during Pleistocene climate fluctuations. The mitochondrial phylogeny pattern conflicts with the current taxonomy.

  15. Renal ischaemia, transient glomerular leak and acute renal tubular damage in patients envenomed by Russell's vipers (Daboia russelii siamensis) in Myanmar.

    PubMed

    Tin-Nu-Swe; Tin-Tun; Myint-Lwin; Thein-Than; Tun-Pe; Robertson, J I; Leckie, B J; Phillips, R E; Warrell, D A

    1993-01-01

    Fifty-two patients who had been bitten by Russell's vipers in Myanmar developed acute renal failure (serum creatinine exceeding 1.3 mg/dL). Thirty-four of them (65%) became oliguric, but the other 18 (35%) maintained a urine output of more than 400 mL/24 h. In oliguric patients, gastrointestinal haemorrhages, renal angle tenderness and conjunctival oedema occurred more commonly, and peak serum creatinine, blood urea nitrogen and the fractional excretion of sodium were significantly higher (P < 0.01) than in non-oliguric patients, indicating a greater degree of renal damage. Urinary concentrations of beta 2 microglobulin and retinol binding protein were raised in most of the patients indicating failure of proximal tubular reabsorption of these proteins, while high urinary N-acetyl glucosaminidase concentrations were consistent with renal tubular damage. Plasma concentrations of active renin were very high, suggesting that renal ischaemia, associated with activation of the renin-angiotensin system, was involved in the development of renal dysfunction.

  16. Stellar mass assembly and star formation history from z=0.2 out to z=6 in the COSMOS and VIPERS fields

    NASA Astrophysics Data System (ADS)

    Ilbert, Olivier

    2015-08-01

    A clear and comprehensive picture describing the physical processes which regulate the stellar mass assembly is still missing in galaxy formation scenario. I will present a measurement of the galaxy stellar mass function and stellar mass density from z=0.2 out to z=6. Our study relies on deep near-infrared imaging over wide fields: the WIRCAM/CFHT coverage of the 20 sq-deg VIPERS fields combined with the new IRAC/Spitzer coverage (the SPLASH survey) of the 2 sq-deg COSMOS field. Our analysis is based on photometric redshifts of 1,5 million of galaxies reaching a precision around 4% at 4

  17. Cytotoxic activities of [Ser⁴⁹]phospholipase A₂ from the venom of the saw-scaled vipers Echis ocellatus, Echis pyramidum leakeyi, Echis carinatus sochureki, and Echis coloratus.

    PubMed

    Conlon, J Michael; Attoub, Samir; Arafat, Hama; Mechkarska, Milena; Casewell, Nicholas R; Harrison, Robert A; Calvete, Juan J

    2013-09-01

    Fractionation by reversed-phase HPLC of venom from four species of saw-scaled viper: Echis ocellatus, Echis pyramidum leakeyi, Echis carinatus sochureki, and Echis coloratus led to identification in each sample of an abundant protein with cytotoxic activity against human non-small cell lung adenocarcinoma A549 cells. The active component in each case was identified by MALDI-TOF mass fingerprinting of tryptic digests as [Ser⁴⁹]phospholipase A₂ ([Ser⁴⁹]PLA₂). An isoform of [Ser⁴⁹]PLA₂ containing the single Ala¹⁸→ Val substitution and a partially characterized [Asp⁴⁹]PLA₂ were also present in the E. coloratus venom. LC₅₀ values against A549 cells for the purified [Ser⁴⁹]PLA₂ proteins from the four species are in the range 2.9-8.5 μM. This range is not significantly different from the range of LC₅₀ values against human umbilical vein endothelial HUVEC cells (2.5-12.2 μM) indicating that the [Ser⁴⁹]PLA₂ proteins show no differential anti-tumor activity. The LC₅₀ value for [Ser⁴⁹]PLA₂ from E. ocellatus against human erythrocytes is >100 μM and the MIC values against Escherichia coli and Staphylococcus aureus are >100 μM. It is suggested that the [Ser⁴⁹]PLA₂ proteins play a major role in producing local tissue necrosis and hemorrhage at the site of envenomation.

  18. Understanding traditional African healing

    PubMed Central

    MOKGOBI, M.G.

    2015-01-01

    Traditional African healing has been in existence for many centuries yet many people still seem not to understand how it relates to God and religion/spirituality. Some people seem to believe that traditional healers worship the ancestors and not God. It is therefore the aim of this paper to clarify this relationship by discussing a chain of communication between the worshipers and the Almighty God. Other aspects of traditional healing namely types of traditional healers, training of traditional healers as well as the role of traditional healers in their communities are discussed. In conclusion, the services of traditional healers go far beyond the uses of herbs for physical illnesses. Traditional healers serve many roles which include but not limited to custodians of the traditional African religion and customs, educators about culture, counselors, social workers and psychologists. PMID:26594664

  19. Ectoparasites of African Mammals.

    DTIC Science & Technology

    1976-11-30

    This study consisted of ectoparasites from approximately 100,000 African small mammals, representing probably more than 500 species of which many are...study of ectoparasites may provide information concerning interactions among animal reservoirs of disease, and (3) an understanding of ecological...parameters for ectoparasites and their hosts may enhance understanding of epidemiological patterns. Of the four major groups dealt with, considerably more

  20. The VIMOS Public Extragalactic Redshift Survey (VIPERS). A precise measurement of the galaxy stellar mass function and the abundance of massive galaxies at redshifts 0.5 < z < 1.3

    NASA Astrophysics Data System (ADS)

    Davidzon, I.; Bolzonella, M.; Coupon, J.; Ilbert, O.; Arnouts, S.; de la Torre, S.; Fritz, A.; De Lucia, G.; Iovino, A.; Granett, B. R.; Zamorani, G.; Guzzo, L.; Abbas, U.; Adami, C.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Cucciati, O.; Franzetti, P.; Fumana, M.; Garilli, B.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Peacock, J. A.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Moutard, T.; Nichol, R. C.; Percival, W. J.; Phleps, S.; Wolk, M.

    2013-10-01

    We measure the evolution of the galaxy stellar mass function from z = 1.3 to z = 0.5 using the first 53 608 redshifts of the ongoing VIMOS Public Extragalactic Survey (VIPERS). Thanks to its large volume and depth, VIPERS provides a detailed picture of the galaxy distribution at z ≃ 0.8, when the Universe was ≃7 Gyr old. We carefully estimate the uncertainties and systematic effects associated with the SED fitting procedure used to derive galaxy stellar masses. We estimate the galaxy stellar mass function at several epochs between z = 0.5 and 1.3, discussing the amount of cosmic variance affecting our estimate in detail. We find that Poisson noise and cosmic variance of the galaxy mass function in the VIPERS survey are comparable to the statistical uncertainties of large surveys in the local universe. VIPERS data allow us to determine with unprecedented accuracy the high-mass tail of the galaxy stellar mass function, which includes a significant number of galaxies that are too rare to detect with any of the past spectroscopic surveys. At the epochs sampled by VIPERS, massive galaxies had already assembled most of their stellar mass. We compare our results with both previous observations and theoretical models. We apply a photometric classification in the (U - V) rest-frame colour to compute the mass function of blue and red galaxies, finding evidence for the evolution of their contribution to the total number density budget: the transition mass above which red galaxies dominate is found to be about 1010.4 ℳ⊙ at z ≃ 0.55, and it evolves proportionally to (1 + z)3. We are able to separately trace the evolution of the number density of blue and red galaxies with masses above 1011.4 ℳ⊙, in a mass range barely studied in previous work. We find that for such high masses, red galaxies show a milder evolution with redshift, when compared to objects at lower masses. At the same time, we detect a population of similarly massive blue galaxies, which are no

  1. Diversity among African Pygmies

    PubMed Central

    Ramírez Rozzi, Fernando V.; Sardi, Marina L.

    2010-01-01

    Although dissimilarities in cranial and post-cranial morphology among African pygmies groups have been recognized, comparative studies on skull morphology usually pull all pygmies together assuming that morphological characters are similar among them and different with respect to other populations. The main aim of this study is to compare cranial morphology between African pygmies and non-pygmies populations from Equatorial Africa derived from both the Eastern and the Western regions in order to test if the greatest morphological difference is obtained in the comparison between pygmies and non-pygmies. Thirty three-dimensional (3D) landmarks registered with Microscribe in four cranial samples (Western and Eastern pygmies and non-pygmies) were obtained. Multivariate analysis (generalized Procrustes analysis, Mahalanobis distances, multivariate regression) and complementary dimensions of size were evaluated with ANOVA and post hoc LSD. Results suggest that important cranial shape differentiation does occur between pygmies and non-pygmies but also between Eastern and Western populations and that size changes and allometries do not affect similarly Eastern and Western pygmies. Therefore, our findings raise serious doubt about the fact to consider African pygmies as a homogenous group in studies on skull morphology. Differences in cranial morphology among pygmies would suggest differentiation after divergence. Although not directly related to skull differentiation, the diversity among pygmies would probably suggest that the process responsible for reduced stature occurred after the split of the ancestors of modern Eastern and Western pygmies. PMID:21049030

  2. Human African trypanosomiasis.

    PubMed

    Lejon, Veerle; Bentivoglio, Marina; Franco, José Ramon

    2013-01-01

    Human African trypanosomiasis or sleeping sickness is a neglected tropical disease that affects populations in sub-Saharan Africa. The disease is caused by infection with the gambiense and rhodesiense subspecies of the extracellular parasite Trypanosoma brucei, and is transmitted to humans by bites of infected tsetse flies. The disease evolves in two stages, the hemolymphatic and meningoencephalitic stages, the latter being defined by central nervous system infection after trypanosomal traversal of the blood-brain barrier. African trypanosomiasis, which leads to severe neuroinflammation, is fatal without treatment, but the available drugs are toxic and complicated to administer. The choice of medication is determined by the infecting parasite subspecies and disease stage. Clinical features include a constellation of nonspecific symptoms and signs with evolving neurological and psychiatric alterations and characteristic sleep-wake disturbances. Because of the clinical profile variability and insidiously progressive central nervous system involvement, disease staging is currently based on cerebrospinal fluid examination, which is usually performed after the finding of trypanosomes in blood or other body fluids. No vaccine being available, control of human African trypanosomiasis relies on diagnosis and treatment of infected patients, assisted by vector control. Better diagnostic tools and safer, easy to use drugs are needed to facilitate elimination of the disease.

  3. East African Rift Valley, Kenya

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This rare, cloud free view of the East African Rift Valley, Kenya (1.5N, 35.5E) shows a clear view of the Turkwell River Valley, an offshoot of the African REift System. The East African Rift is part of a vast plate fracture which extends from southern Turkey, through the Red Sea, East Africa and into Mozambique. Dark green patches of forests are seen along the rift margin and tea plantations occupy the cooler higher ground.

  4. Inhibition of secretary PLA₂--VRV-PL-VIIIa of Russell's viper venom by standard aqueous stem bark extract of Mangifera indica L.

    PubMed

    Dhananjaya, B L; Sudarshan, S

    2015-03-01

    The aqueous extract of Mangifera indica is known to possess anti-snake venom activities. However, its inhibitory potency and mechanism of action on multi-toxic phospholipases A2s, which are the most toxic and lethal component of snake venom is still unknown. Therefore, this study was carried out to evaluate the modulatory effect of standard aqueous bark extract of M. indica on VRV-PL-VIIIa of Indian Russells viper venom. Mangifera indica extract dose dependently inhibited the GIIB sPLA2 (VRV-PL-VIIIa) activity with an IC50 value of 6.8±0.3 μg/ml. M. indica extract effectively inhibited the indirect hemolytic activity up to 96% at ~40 μg/ml concentration. Further, M. indica extract at different concentrations (0-50 μg/ml) inhibited the edema formed in a dose dependent manner. It was found that there was no relieve of inhibitory effect of the extract when examined as a function of increased substrate and calcium concentration. The inhibition was irreversible as evident from binding studies. The in vitro inhibition is well correlated with in situ and in vivo edema inducing activities. As the inhibition is independent of substrate, calcium concentration and was irreversible, it can be concluded that M. indica extracts mode of inhibition could be due to direct interaction of components present in the extract with PLA2 enzyme. In conclusion, the aqueous extract of M. indica effectively inhibits svPLA2 (Snake venom phospholipase A2) enzymatic and its associated toxic activities, which substantiate its anti-snake venom properties. Further in-depth studies are interesting to known on the role and mechanism of the principal inhibitory constituents present in the extract, so as to develop them into potent anti-snake venom and as an anti-inflammatory agent.

  5. Venom lethality and diet: differential responses of natural prey and model organisms to the venom of the saw-scaled vipers (Echis).

    PubMed

    Richards, D P; Barlow, A; Wüster, W

    2012-01-01

    The composition of snake venoms shows a high degree of variation at all taxonomic levels, and natural selection for diet has been implicated as a potential cause. Saw-scaled vipers (Echis) provide a good model for studying this phenomenon. The venoms of arthropod feeding species of Echis are significantly more toxic to natural scorpion prey than those of species which feed predominantly upon vertebrate prey. Although testing venom activity on natural prey is important for our understanding of the evolution of venom, natural prey species are often difficult to obtain in sufficient numbers for toxinological work. In order to test the viability of using cheaper and more easily available model organisms for toxicity assessments in evolutionary research, and the extent to which toxicity of arthropod-eating Echis venoms is increased to arthropods in general or targeted to certain groups, we conducted median lethal dosage (LD(50)) and time to death trials using the desert locust (Schistocerca gregaria) as a model arthropod, rarely consumed by wild Echis. The venoms of arthropod specialist Echis were found to be significantly more toxic to locusts than the venom of a vertebrate feeding outgroup (Bitis arietans), and one arthropod specialist venom was found to be more toxic than those species which feed upon arthropods infrequently or not at all. The venoms of arthropod specialists were also found to cause death and incapacitation faster than the vertebrate feeding outgroup. Despite some similarity of trends, there are considerable differences between the response of natural prey (scorpions) and a model arthropod (locust) to the venoms of Echis species. This suggests that when possible, natural prey rather than convenient model organisms should be used to gain an understanding of the functional significance of variation in venom composition in snakes.

  6. Detection of Trichomonas vaginalis DNA by use of self-obtained vaginal swabs with the BD ProbeTec Qx assay on the BD Viper system.

    PubMed

    Van Der Pol, Barbara; Williams, James A; Taylor, Stephanie N; Cammarata, Catherine L; Rivers, Charles A; Body, Barbara A; Nye, Melinda; Fuller, Deanna; Schwebke, Jane R; Barnes, Mathilda; Gaydos, Charlotte A

    2014-03-01

    Trichomonas vaginalis is the most prevalent nonviral sexually transmitted infection worldwide, and improved diagnostic methods are critical for controlling this pathogen. Diagnostic assays that can be used in conjunction with routine chlamydia/gonorrhea nucleic acid-based screening are likely to have the most impact on disease control. Here we describe the performance of the new BD T. vaginalis Qx (TVQ) amplified DNA assay, which can be performed on the automated BD Viper system. We focus on data from vaginal swab samples, since this is the specimen type routinely used for traditional trichomonas testing and the recommended specimen type for chlamydia/gonorrhea screening. Vaginal swabs were obtained from women attending sexually transmitted disease or family planning clinics at 7 sites. Patient-collected vaginal swabs were tested by the TVQ assay, and the Aptima T. vaginalis (ATV) assay was performed using clinician-collected vaginal swabs. Additional clinician-collected vaginal swabs were used for the wet mount and culture methods. Analyses included comparisons versus the patient infection status (PIS) defined by positive results with the wet mount method or culture, direct comparisons assessed with κ scores, and latent class analysis (LCA) as an unbiased estimator of test accuracy. Data from 838 women, 116 of whom were infected with T. vaginalis, were analyzed. The TVQ assay sensitivity and specificity estimates based on the PIS were 98.3% and 99.0%, respectively. The TVQ assay was similar to the ATV assay (κ=0.938) in direct analysis. LCA estimated the TVQ sensitivity and specificity as 98.3 and 99.6%, respectively. The TVQ assay performed well using self-collected vaginal swabs, the optimal sample type, as recommended by the CDC for chlamydia/gonorrhea screening among women.

  7. Elder Abuse among African Americans

    ERIC Educational Resources Information Center

    Tauriac, Jesse J.; Scruggs, Natoschia

    2006-01-01

    Perceptions of extreme, moderate, and mild forms of elder abuse among African-American women (n=25) and men (n=10) were examined. African-American respondents emphasized physical abuse when giving examples of extremely abusive behavior. Along with physical abuse, verbal abuse was the most frequently identified form of abuse, and was significantly…

  8. African ethics and voluntary euthanasia.

    PubMed

    Omonzejele, P F

    2004-01-01

    This paper outlines the relationship between euthanasia and its ethical norms and practices in a part of West Africa. The various sub-types of euthanasia are described in detail, parallel with the role of African ethical theories in determining their relevance. The author discusses the implications of this approach relative to the social and economic state of African communities.

  9. African American Administrators and Staff

    ERIC Educational Resources Information Center

    Wright, Dianne; Taylor, Janice D.; Burrell, Charlotte; Stewart, Gregory

    2006-01-01

    This article explores the issues of African American participation in the administrative ranks of the academy. The authors find that African Americans tend to hold positions that are marginal in academic organizations, lacking power and influence, and that not much has changed over recent decades. Forces influencing this condition are explored,…

  10. African-Americans and Alcoholism.

    ERIC Educational Resources Information Center

    Sigmon, Scott B.

    To better serve people in a counseling relationship, it is useful to understand them not only culturally, but demographically as well. This paper traces historical, religious, demographic aspects and treatment of alcohol abuse in African Americans. Historically, alcohol abuse and alcohol dependence have varied for African Americans. During the…

  11. Africanization in the United States

    PubMed Central

    Pinto, M. Alice; Rubink, William L.; Patton, John C.; Coulson, Robert N.; Johnston, J. Spencer

    2005-01-01

    The expansion of Africanized honeybees from South America to the southwestern United States in <50 years is considered one of the most spectacular biological invasions yet documented. In the American tropics, it has been shown that during their expansion Africanized honeybees have low levels of introgressed alleles from resident European populations. In the United States, it has been speculated, but not shown, that Africanized honeybees would hybridize extensively with European honeybees. Here we report a continuous 11-year study investigating temporal changes in the genetic structure of a feral population from the southern United States undergoing Africanization. Our microsatellite data showed that (1) the process of Africanization involved both maternal and paternal bidirectional gene flow between European and Africanized honeybees and (2) the panmitic European population was replaced by panmitic mixtures of A. m. scutellata and European genes within 5 years after Africanization. The post-Africanization gene pool (1998–2001) was composed of a diverse array of recombinant classes with a substantial European genetic contribution (mean 25–37%). Therefore, the resulting feral honeybee population of south Texas was best viewed as a hybrid swarm. PMID:15937139

  12. Cancer statistics for African Americans.

    PubMed

    Ghafoor, Asma; Jemal, Ahmedin; Cokkinides, Vilma; Cardinez, Cheryll; Murray, Taylor; Samuels, Alicia; Thun, Michael J

    2002-01-01

    The American Cancer Society provides estimates on the number of new cancer cases and deaths, and compiles health statistics on African Americans in a biennial publication, Cancer Facts and Figures for African Americans. The compiled statistics include cancer incidence, mortality, survival, and lifestyle behaviors using the most recent data on incidence and survival from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) program, mortality data from the National Center for Health Statistics (NCHS), and behavioral information from the Behavior Risk Factor Surveillance System (BRFSS), Youth Risk Behavior Surveillance System (YRBSS), and National Health Interview Survey (NHIS). It is estimated that 132,700 new cases of cancer and 63,100 deaths will occur among African Americans in the year 2003. Although African Americans have experienced higher incidence and mortality rates of cancer than whites for many years, incidence rates have declined by 2.7 percent per year in African-American males since 1992, while stabilizing in African-American females. During the same period, death rates declined by 2.1 percent and 0.4 percent per year among African-American males and females, respectively. The decrease in both incidence and death rates from cancer among African-American males was the largest of any racial or ethnic group. Nonetheless, African Americans still carry the highest cancer burden among US racial and ethnic groups. Most cancers detectable by screening are diagnosed at a later stage and survival rates are lower within each stage of disease in African Americans than in whites. The extent to which these disparities reflect unequal access to health care versus other factors is an active area of research.

  13. Phylogeny and diversification of mountain vipers (Montivipera, Nilson et al., 2001) triggered by multiple Plio-Pleistocene refugia and high-mountain topography in the Near and Middle East.

    PubMed

    Stümpel, Nikolaus; Rajabizadeh, Mehdi; Avcı, Aziz; Wüster, Wolfgang; Joger, Ulrich

    2016-08-01

    The Near and Middle East is a hotspot of biodiversity, but the region remains underexplored at the level of genetic biodiversity. Here, we present an extensive molecular phylogeny of the viperid snake genus Montivipera, including all known taxa. Based on nuclear and mitochondrial data, we present novel insights into the phylogeny of the genus and review the status of its constituent species. Maximum likelihood methods revealed a montane origin of Montivipera at 12.3Mya. We then analyzed factors of mountain viper diversity. Our data support substantial changes in effective population size through Plio-Pleistocene periods. We conclude that climatic oscillations were drivers of allopatric speciation, and that mountain systems of the Near and Middle East have strongly influenced the evolution and survival of taxa, because climatic and topographical heterogeneities induced by mountains have played a crucial role as filters for dispersal and as multiple refugia. The wide diversity of montane microhabitats enabled mountain vipers to retain their ecological niche during climatic pessima. In consequence the varied geological and topographical conditions between refugia favoured genetic isolation and created patterns of species richness resulting in the formation of neoendemic taxa. Our data support high concordance between geographic distributions of Montivipera haplotypes with putative plant refugia.

  14. East African ROAD

    NASA Astrophysics Data System (ADS)

    Tekle, Kelali

    2016-10-01

    In the developing world astronomy had been treated as the science of elites. As a result of this overwhelming perception, astronomy compared with other applied sciences has got less attention and its role in development has been insignificant. However, the IAU General Assembly decision in 2009 opened new opportunity for countries and professionals to deeply look into Astronomy and its role in development. Then, the subsequent establishment of regional offices in the developing world is helping countries to integrate astronomy with other earth and space based sciences so as to progressively promote its scientific and development importance. Gradually nations have come to know that space is the frontier of tomorrow and the urgency of preeminence on space frontier starts at primary school and ascends to tertiary education. For this to happen, member nations in east African region have placed STEM education at the center of their education system. For instance, Ethiopian has changed University enrollment strategy to be in favor of science and engineering subjects, i.e. every year seventy percent of new University entrants join science and engineering fields while thirty percent social science and humanities. Such bold actions truly promote astronomy to be conceived as gateway to science and technology. To promote the concept of astronomy for development the East African regional office has actually aligned it activities to be in line with the focus areas identified by the IAU strategy (2010 to 2020).

  15. African oil plays

    SciTech Connect

    Clifford, A.J. )

    1989-09-01

    The vast continent of Africa hosts over eight sedimentary basins, covering approximately half its total area. Of these basins, only 82% have entered a mature exploration phase, 9% have had little or no exploration at all. Since oil was first discovered in Africa during the mid-1950s, old play concepts continue to bear fruit, for example in Egypt and Nigeria, while new play concepts promise to become more important, such as in Algeria, Angola, Chad, Egypt, Gabon, and Sudan. The most exciting developments of recent years in African oil exploration are: (1) the Gamba/Dentale play, onshore Gabon; (2) the Pinda play, offshore Angola; (3) the Lucula/Toca play, offshore Cabinda; (4) the Metlaoui play, offshore Libya/Tunisia; (5) the mid-Cretaceous sand play, Chad/Sudan; and (6) the TAG-I/F6 play, onshore Algeria. Examples of these plays are illustrated along with some of the more traditional oil plays. Where are the future oil plays likely to develop No doubt, the Saharan basins of Algeria and Libya will feature strongly, also the presalt of Equatorial West Africa, the Central African Rift System and, more speculatively, offshore Ethiopia and Namibia, and onshore Madagascar, Mozambique, and Tanzania.

  16. Bioenergy and African transformation.

    PubMed

    Lynd, Lee R; Sow, Mariam; Chimphango, Annie Fa; Cortez, Luis Ab; Brito Cruz, Carlos H; Elmissiry, Mosad; Laser, Mark; Mayaki, Ibrahim A; Moraes, Marcia Afd; Nogueira, Luiz Ah; Wolfaardt, Gideon M; Woods, Jeremy; van Zyl, Willem H

    2015-01-01

    Among the world's continents, Africa has the highest incidence of food insecurity and poverty and the highest rates of population growth. Yet Africa also has the most arable land, the lowest crop yields, and by far the most plentiful land resources relative to energy demand. It is thus of interest to examine the potential of expanded modern bioenergy production in Africa. Here we consider bioenergy as an enabler for development, and provide an overview of modern bioenergy technologies with a comment on application in an Africa context. Experience with bioenergy in Africa offers evidence of social benefits and also some important lessons. In Brazil, social development, agricultural development and food security, and bioenergy development have been synergistic rather than antagonistic. Realizing similar success in African countries will require clear vision, good governance, and adaptation of technologies, knowledge, and business models to myriad local circumstances. Strategies for integrated production of food crops, livestock, and bioenergy are potentially attractive and offer an alternative to an agricultural model featuring specialized land use. If done thoughtfully, there is considerable evidence that food security and economic development in Africa can be addressed more effectively with modern bioenergy than without it. Modern bioenergy can be an agent of African transformation, with potential social benefits accruing to multiple sectors and extending well beyond energy supply per se. Potential negative impacts also cut across sectors. Thus, institutionally inclusive multi-sector legislative structures will be more effective at maximizing the social benefits of bioenergy compared to institutionally exclusive, single-sector structures.

  17. A Bibliography of African Languages and Linguistics.

    ERIC Educational Resources Information Center

    Murphy, John D., Comp.; Goff, Harry, Comp.

    The present bibliography of African languages and linguistics includes not only works relating to the "Negro-African" languages, but also those dealing with the African varieties of Arabic, the Hamitic languages, Malagasy, Afrikaans, and various Creoles. (The greater part of the entries relate to the indigenous languages of the African continent…

  18. The African Millennium Villages

    PubMed Central

    Sanchez, Pedro; Palm, Cheryl; Sachs, Jeffrey; Denning, Glenn; Flor, Rafael; Harawa, Rebbie; Jama, Bashir; Kiflemariam, Tsegazeab; Konecky, Bronwen; Kozar, Raffaela; Lelerai, Eliud; Malik, Alia; Modi, Vijay; Mutuo, Patrick; Niang, Amadou; Okoth, Herine; Place, Frank; Sachs, Sonia Ehrlich; Said, Amir; Siriri, David; Teklehaimanot, Awash; Wang, Karen; Wangila, Justine; Zamba, Colleen

    2007-01-01

    We describe the concept, strategy, and initial results of the Millennium Villages Project and implications regarding sustainability and scalability. Our underlying hypothesis is that the interacting crises of agriculture, health, and infrastructure in rural Africa can be overcome through targeted public-sector investments to raise rural productivity and, thereby, to increased private-sector saving and investments. This is carried out by empowering impoverished communities with science-based interventions. Seventy-eight Millennium Villages have been initiated in 12 sites in 10 African countries, each representing a major agroecological zone. In early results, the research villages in Kenya, Ethiopia, and Malawi have reduced malaria prevalence, met caloric requirements, generated crop surpluses, enabled school feeding programs, and provided cash earnings for farm families. PMID:17942701

  19. [African population in history].

    PubMed

    Yang, S

    1984-11-29

    The growth rate of the African population has been fluctuating throughout history, affected by political, social, and economic events. 6000 years ago, the majority of the population was based in North Africa, because farming had been developed there. However, between the 11th and the 16th centuries, there was a constant decline in the population of that region, due to invasions from Europe and the black plague. During the same period, the population in the area south of the Sahara grew rapidly, as people there had gone into the iron tool period and farming had been developed. From the 16th to the mid-17th Century, population growth was considerable in Africa; more people had learned the technology of irrigation, corn and potatoes had been introduced from South America, and colonialism was not yet an issue. From the mid-17th to the mid-19th Century, there was no growth, due to the slave trade and wars between tribes. One estimate sets the direct and indirect loss during this period, as a result of the slave trade, at 100 million people. From the 1850s to the end of World War I, population growth started up again, chiefly influenced by the fact that the slave trade had essentially come to a half and modern medical care had become available on the continent. However, in central Africa, the region which suffered the worst blow from the slave trade, growth was very slow, while in East Africa the population was declining because of wars between colonists and natives, as well as natural disasters. Increases in population during this period were a result of immigration from Europe and India. From the end of World War I to the present, growth has been rapid, given improvements in medical services and standards of living, while most of the former colonies became independent after the 1950s. Consequently, almost all African countries are under great pressure now with regard to their populations.

  20. Central African Republic.

    PubMed

    1989-11-01

    The Central African Republic contains 242,000 square miles, which rolling terrain almost 2000 feet above sea level. The climate is tropical, and it has a population of 2.8 million people with a 2.5% growth rate. There are more than 80 ethnic groups including Baya 34%, Banda 28%, Sara 10%, Mandja 9%, Mboum 9%, and M'Baka 7%. The religions are traditional African 35%, protestant 25%, Roman Catholic 25%, and Muslim 15%, and the languages are French and Sangho. The infant mortality rate is 143/1000, with expectancy at 49 years and a 40% literacy rate. The work force of 1 million is 70% agricultural, industry 6% and commerce and service 6% and government 3%. The government consists of a president assisted by cabinet ministers and a single party. Natural resources include diamonds, uranium, timber, gold, and oil, and major industries are beverages, textiles, and soap. Agricultural products feature coffee, cotton, peanuts, tobacco, food crops and livestock. Most of the population live in rural areas and most of the 80 ethnic groups have their own language. This is one of the world's least developed countries, with a per capita income of $375/year. The main problems with development are the poor transportation infrastructure, and the weak internal and international marketing systems. The US and various international organizations have aided in agriculture development, health programs, and family planning. US investment is mainly in diamond and gold mining, and although oil drilling has been successful it is not economically feasible at current prices.

  1. African Passages: Journaling through Archetypes.

    ERIC Educational Resources Information Center

    Spencer, Patricia

    1990-01-01

    Explores how students (through an awareness of literary archetypes and journal writing) can use African stories to cross cultures, time, and continents, making connections between their worlds and the worlds of others. (MG)

  2. Early African Hominids: Pedagogic Patterns.

    ERIC Educational Resources Information Center

    Newman, James L.

    1984-01-01

    By studying early African hominids, students can learn about the interactive testing and creative aspects of scientific thinking and sharpen their geographical skills. It is impossible to study this topic without giving prominence to space and time. (RM)

  3. African-Americans and Alzheimer's

    MedlinePlus

    ... African-Americans are at a higher risk for Alzheimer's disease. Many Americans dismiss the warning signs of Alzheimer's, ... two times more likely to develop late-onset Alzheimer's disease than whites and less likely to have a ...

  4. Randomised Controlled Double-Blind Non-Inferiority Trial of Two Antivenoms for Saw-Scaled or Carpet Viper (Echis ocellatus) Envenoming in Nigeria

    PubMed Central

    Abubakar, Isa S.; Abubakar, Saidu B.; Habib, Abdulrazaq G.; Nasidi, Abdulsalam; Durfa, Nandul; Yusuf, Peter O.; Garnvwa, John; Sokomba, Elijah; Salako, Lateef; Theakston, R. David G; Juszczak, Ed; Alder, Nicola; Warrell, David A.

    2010-01-01

    Background In West Africa, envenoming by saw-scaled or carpet vipers (Echis ocellatus) causes great morbidity and mortality, but there is a crisis in supply of effective and affordable antivenom (ISRCTN01257358). Methods In a randomised, double-blind, controlled, non-inferiority trial, “EchiTAb Plus-ICP” (ET-Plus) equine antivenom made by Instituto Clodomiro Picado was compared to “EchiTAb G” (ET-G) ovine antivenom made by MicroPharm, which is the standard of care in Nigeria and was developed from the original EchiTAb-Fab introduced in 1998. Both are caprylic acid purified whole IgG antivenoms. ET-G is monospecific for Echis ocellatus antivenom (initial dose 1 vial) and ET-Plus is polyspecific for E. ocellatus, Naja nigricollis and Bitis arietans (initial dose 3 vials). Both had been screened by pre-clinical and preliminary clinical dose-finding and safety studies. Patients who presented with incoagulable blood, indicative of systemic envenoming by E. ocellatus, were recruited in Kaltungo, north-eastern Nigeria. Those eligible and consenting were randomly allocated with equal probability to receive ET-Plus or ET-G. The primary outcome was permanent restoration of blood coagulability 6 hours after the start of treatment, assessed by a simple whole blood clotting test repeated 6, 12, 18, 24 and 48 hr after treatment. Secondary (safety) outcomes were the incidences of anaphylactic, pyrogenic and late serum sickness-type antivenom reactions. Findings Initial doses permanently restored blood coagulability at 6 hours in 161/194 (83.0%) of ET-Plus and 156/206 (75.7%) of ET-G treated patients (Relative Risk [RR] 1.10 one-sided 95% CI lower limit 1.01; P = 0.05). ET-Plus caused early reactions on more occasions than did ET-G [50/194 (25.8%) and 39/206 (18.9%) respectively RR (1.36 one-sided 95% CI 1.86 upper limit; P = 0.06). These reactions were classified as severe in 21 (10.8%) and 11 (5.3%) of patients, respectively. Conclusion At these doses, ET

  5. The neuromuscular activity of Bothriopsis bilineata smaragdina (forest viper) venom and its toxin Bbil-TX (Asp49 phospholipase A2) on isolated mouse nerve-muscle preparations.

    PubMed

    Floriano, Rafael Stuani; Rocha, Thalita; Carregari, Victor Corasolla; Marangoni, Sergio; da Cruz-Höfling, Maria Alice; Hyslop, Stephen; Rodrigues-Simioni, Léa; Rowan, Edward G

    2015-03-01

    The presynaptic action of Bothriopsis bilineata smaragdina (forest viper) venom and Bbil-TX, an Asp49 PLA2 from this venom, was examined in detail in mouse phrenic nerve-muscle (PND) preparations in vitro and in a neuroblastoma cell line (SK-N-SH) in order to gain a better insight into the mechanism of action of the venom and associated Asp49 PLA2. In low Ca(2+) solution, venom (3μg/ml) caused a quadriphasic response in PND twitch height whilst at 10μg/ml the venom additionally induced an abrupt and marked initial contracture followed by neuromuscular facilitation, rhythmic oscillations of nerve-evoked twitches, alterations in baseline and progressive blockade. The venom slowed the relaxation phase of muscle twitches. In low Ca(2+), Bbil-TX [210nM (3μg/ml)] caused a progressive increase in PND twitch amplitude but no change in the decay time constant. Venom (10μg/ml) and Bbil-TX (210nM) caused minor changes in the compound action potential (CAP) amplitude recorded from sciatic nerve preparations, with no significant effect on rise time and latency; tetrodotoxin (3.1nM) blocked the CAP at the end of the experiments. In mouse triangularis sterni nerve-muscle (TSn-m) preparations, venom (10μg/ml) and Bbil-TX (210nM) significantly reduced the perineural waveform associated with the outward K(+) current while the amplitude of the inward Na(+) current was not significantly affected. Bbil-TX (210nM) caused a progressive increase in the quantal content of TSn-m preparations maintained in low Ca(2+) solution. Venom (3μg/ml) and toxin (210nM) increased the calcium fluorescence in SK-N-SH neuroblastoma cells loaded with Fluo3 AM and maintained in low or normal Ca(2+) solution. In normal Ca(2+), the increase in fluorescence amplitude was accompanied by irregular and frequent calcium transients. In TSn-m preparations loaded with Fluo4 AM, venom (10μg/ml) caused an immediate increase in intracellular Ca(2+) followed by oscillations in fluorescence and muscle contracture

  6. Hepatitis C in African Americans.

    PubMed

    Saab, Sammy; Jackson, Christian; Nieto, Jose; Francois, Fritz

    2014-10-01

    The care of hepatitis C virus (HCV) in African Americans represents an opportunity to address a major health disparity in medicine. In all facets of HCV infection, African Americans are inexplicably affected, including in the prevalence of the virus, which is higher among them compared with most of the racial and ethnic groups. Ironically, although fibrosis rates may be slow, hepatocellular carcinoma and mortality rates appear to be higher among African Americans. Sustained viral response (SVR) rates have historically significantly trailed behind Caucasians. The reasons for this gap in SVR are related to both viral and host factors. Moreover, low enrollment rates in clinical trials hamper the study of the efficacy of anti-viral therapy. Nevertheless, the gap in SVR between African Americans and Caucasians may be narrowing with the use of direct-acting agents. Gastroenterologists, hepatologists, primary care physicians, and other health-care providers need to address modifiable risk factors that affect the natural history, as well as treatment outcomes, for HCV among African Americans. Efforts need to be made to improve awareness among health-care providers to address the differences in screening and referral patterns for African Americans.

  7. The African Pediatric Fellowship Program: Training in Africa for Africans.

    PubMed

    Wilmshurst, Jo M; Morrow, Brenda; du Preez, Avril; Githanga, David; Kennedy, Neil; Zar, Heather J

    2016-01-01

    Africa has a significant burden of childhood disease, with relatively few skilled health care professionals. The African Paediatric Fellowship Programme was developed by the Department of Pediatrics and Child Health at the University of Cape Town to provide relevant training for African child health professionals, by Africans, within Africa. Trainees identified by partner academic institutions spend 6 months to 2 years training in the Department of Pediatrics and allied disciplines. They then return to their home institution to build practice, training, research, and advocacy. From 2008 to 2015, 73 physicians have completed or are completing training in general pediatrics or a pediatric subspecialty. At 1 year posttraining, 98% to 100% are practicing back in their home institution. The impact of the returning fellows is evident from their practice interventions, research collaborations, and positions as stakeholders who can change health care policies. Thirty-three centers in 13 African countries are partners with the program, and the program template is now followed by other partner sites in Africa. Increasing and retaining the skills pool of African child health specialists is building a network of motivated, highly skilled clinicians who are equipped to advance child health in Africa.

  8. Phylogenomics of African guenons.

    PubMed

    Moulin, Sibyle; Gerbault-Seureau, Michèle; Dutrillaux, Bernard; Richard, Florence Anne

    2008-01-01

    The karyotypes of 28 specimens belonging to 26 species of Cercopithecinae have been compared with each other and with human karyotype by chromosome banding and, for some of them, by Zoo-FISH (human painting probes) techniques. The study includes the first description of the karyotypes of four species and a synonym of Cercopithecus nictitans. The chromosomal homologies obtained provide us with new data on a large number of rearrangements. This allows us to code chromosomal characters to draw Cercopithecini phylogenetic trees, which are compared to phylogenetic data based on DNA sequences. Our findings show that some of the superspecies proposed by Kingdon (1997 The Kingdon Field Guide to African Mammals, Academic Press.) and Groves (2001 Primates Taxonomy, Smithsonian Institution Press) do not form homogeneous groups and that the genus Cercopithecus is paraphyletic, in agreement with previous molecular analyses. The evolution of Cercopithecini karyotypes is mainly due to non-centromeric chromosome fissions and centromeric shifts or inversions. Non-Robertsonian translocations occurred in C. hamlyni and C. neglectus. The position of chromosomal rearrangements in the phylogenetic tree leads us to propose that the Cercopithecini evolution proceeded by either repeated fission events facilitated by peculiar genomic structures or successive reticulate phases, in which heterozygous populations for few rearranged chromosomes were present, allowing the spreading of chromosomal forms in various combinations, before the speciation process.

  9. An African ethic for nursing?

    PubMed

    Haegert, S

    2000-11-01

    This article derives from a doctoral thesis in which a particular discourse was used as a 'paradigm case'. From this discourse an ethic set within a South African culture arose. Using many cultural 'voices' to aid the understanding of this narrative, the ethic shows that one can build on both a 'justice' and a 'care' ethic. With further development based on African culture one can take the ethic of care deeper and reveal 'layers of understanding'. Care, together with compassion, forms the foundation of morality. Nursing ethics has followed particular western moral philosophers. Often nursing ethics has been taught along the lines of Kohlberg's theory of morality, with its emphasis on rules, rights, duties and general obligations. These principles were universalistic, masculine and noncontextual. However, there is a new ethical movement among Thomist philosophers along the lines to be expounded in this article. Nurses such as Benner, Bevis, Dunlop, Fry and Gadow--to name but a few--have welcomed the concept of an 'ethic of care'. Gilligan's work gave a feminist view and situated ethics in the everyday aspects of responsiveness, responsibility, context and concern. Shutte's search for a 'philosophy for Africa' has resulted in finding similarities in Setiloane and in Senghor with those of Thomist philosophers. Using this African philosophy and a research participant's narrative, an African ethic evolves out of the African proverb: 'A person is a person through other persons', or its alternative rendering: 'I am because we are: we are because I am.' This hermeneutic narrative reveals 'the way affect imbues activity with ethical meaning' within the context of a black nursing sister in a rural South African hospital. It expands upon the above proverb and incorporates the South African constitutional idea of 'Ubuntu' (compassion and justice or humanness).

  10. African American Preschoolers' Language, Emergent Literacy Skills, and Use of African American English: A Complex Relation

    ERIC Educational Resources Information Center

    Connor, Carol McDonald; Craig, Holly K.

    2006-01-01

    Purpose: This study examined the relation between African American preschoolers' use of African American English (AAE) and their language and emergent literacy skills in an effort to better understand the perplexing and persistent difficulties many African American children experience learning to read proficiently. Method: African American…

  11. Technical Consulting: The African-American Perspective

    ERIC Educational Resources Information Center

    Whitfield, Tracy N.

    2010-01-01

    The qualitative research study explored the organizational characteristics necessary in addressing the low concentration of African American technical consultants employed in the information technology industry. Using research participants' professional experience, participants responded to a developed questionnaire. African American technical…

  12. African N Assessment

    NASA Astrophysics Data System (ADS)

    Bekunda, M.; Galford, G. L.; Hickman, J. E.; Palm, C.

    2011-12-01

    Africa's smallholder agricultural systems face unique challenges in planning for reducing poverty, concurrent with adaptation and mitigation to climate change. At continental level, policy seeks to promote a uniquely African Green Revolution to increase crop yields and food production, and improve local livelihoods. However, the consequences on the environment and climate are not clear; these pro-economic development measures should be linked to climate change adaptation and mitigation measures, and research is required to help achieve these policy proposals by identifying options, and testing impacts. In particular, increased nitrogen (N) inputs are essential for increasing food production in Africa, but are accompanied by inevitable increases in losses to the environment. These losses appear to be low at input levels promoted in agricultural development programs, while the increased N inputs both increase current food production and appear to reduce the vulnerability of food production to changes in climate. We present field and remote sensing evidence from Malawi that subsidizing improved seed and fertilizers increases resilience to drought without adding excess N to the environment. In Kenya, field research identified thresholds in N2O losses, where emissions are very low at fertilization rates of less than 200 kg ha-1. Village-scale models have identified potential inefficiencies in the food production process where the largest losses of reactive N occur, and which could be targeted to reduce the amount of N released to the environment. We further review some on-going research activities and progress in Africa that compare different methods of managing resources that target resilience in food production and adaptation to climate change, using nutrient N as an indicator, while evaluating the effects of these resource management practices on ecosystems and the environment.

  13. Plio-pleistocene African climate

    SciTech Connect

    deMenocal, P.B.

    1995-10-06

    Marine records of African climate variability document a shift toward more arid conditions after 2.8 million years ago (Ma), evidently resulting from remote forcing by cold North Atlantic sea-surface temperatures associated with the onset of Northern Hemisphere glacial cycles. African climate before 2.8 Ma was regulated by low-latitude insolation forcing of monsoonal climate due to Earth orbital precession. Major steps in the evolution of African hominids and other vertebrates are coincident with shifts to more arid, open conditions near 2.8 Ma, 1.7 Ma, and 1.0 Ma, suggesting that some Pliocene (Plio)-Pleistocene speciation events may have been climatically mediated. 65 refs., 6 figs.

  14. Plio-Pleistocene African Climate

    NASA Astrophysics Data System (ADS)

    Demenocal, Peter B.

    1995-10-01

    Marine records of African climate variability document a shift toward more arid conditions after 2.8 million years ago (Ma), evidently resulting from remote forcing by cold North Atlantic sea-surface temperatures associated with the onset of Northern Hemisphere glacial cycles. African climate before 2.8 Ma was regulated by low-latitude insolation forcing of monsoonal climate due to Earth orbital precession. Major steps in the evolution of African hominids and other vertebrates are coincident with shifts to more arid, open conditions near 2.8 Ma, 1.7 Ma, and 1.0 Ma, suggesting that some Pliocene (Plio)-Pleistocene speciation events may have been climatically mediated.

  15. African perceptions of female attractiveness.

    PubMed

    Coetzee, Vinet; Faerber, Stella J; Greeff, Jaco M; Lefevre, Carmen E; Re, Daniel E; Perrett, David I

    2012-01-01

    Little is known about mate choice preferences outside Western, educated, industrialised, rich and democratic societies, even though these Western populations may be particularly unrepresentative of human populations. To our knowledge, this is the first study to test which facial cues contribute to African perceptions of African female attractiveness and also the first study to test the combined role of facial adiposity, skin colour (lightness, yellowness and redness), skin homogeneity and youthfulness in the facial attractiveness preferences of any population. Results show that youthfulness, skin colour, skin homogeneity and facial adiposity significantly and independently predict attractiveness in female African faces. Younger, thinner women with a lighter, yellower skin colour and a more homogenous skin tone are considered more attractive. These findings provide a more global perspective on human mate choice and point to a universal role for these four facial cues in female facial attractiveness.

  16. The African Cultural Astronomy Project

    NASA Astrophysics Data System (ADS)

    Urama, Johnson O.; Holbrook, Jarita C.

    2011-06-01

    Indigenous, endogenous, traditional, or cultural astronomy focuses on the many ways that people and cultures interact with celestial bodies. In most parts of Africa, there is very little or no awareness about modern astronomy. However, like ancient people everywhere, Africans wondered at the sky and struggled to make sense of it. The African Cultural Astronomy Project aims to unearth the body of traditional knowledge of astronomy possessed by peoples of the different ethnic groups in Africa and to consider scientific interpretations when appropriate for cosmogonies and ancient astronomical practices. Regardless of scientific validity, every scientist can relate to the process of making observations and creating theoretical mechanisms for explaining what is observed. Through linking the traditional and the scientific, it is believed that this would be used to create awareness and interest in astronomy in most parts of Africa. This paper discusses the vision, challenges and prospects of the African Cultural Astronomy Project in her quest to popularize astronomy in Africa.

  17. Towards a Norm in South African Englishes.

    ERIC Educational Resources Information Center

    van der Walt, Johann L.; van Rooy, Bertus

    2002-01-01

    Investigates the perception and application of the norm in South African English with specific reference to Black South African English. Hypothesizes that South African English is in the hibernation and expansion phase. Three sets of data are presented and analyzed. (Author/VWL)

  18. African American Teaching and the Matriarchal Performance.

    ERIC Educational Resources Information Center

    Jeffries, Rhonda Baynes

    This paper discusses the role of matriarchs in African-American culture, explaining that traditionally, African-American matriarchs arise from a combination of African norms and American social positions that naturally forces them to assume leadership conditions. The roles these women assume are a response to the desire to survive in a society…

  19. Freedom Road: Adult Education of African Americans.

    ERIC Educational Resources Information Center

    Peterson, Elizabeth A., Ed.

    This book contains six chapters by various authors about the history of African Americans' contributions and participation in adult education. The book reports on how some African American leaders saw the connection between education and the eventual freedom or uplift of the African American people. Following a foreword (Phyllis M. Cunningham) and…

  20. Engaging African Americans in Smoking Cessation Programs

    ERIC Educational Resources Information Center

    Wallen, Jacqueline; Randolph, Suzanne; Carter-Pokras, Olivia; Feldman, Robert; Kanamori-Nishimura, Mariano

    2014-01-01

    Background: African Americans are disproportionately exposed to and targeted by prosmoking advertisements, particularly menthol cigarette ads. Though African Americans begin smoking later than whites, they are less likely to quit smoking than whites. Purpose: This study was designed to explore African American smoking cessation attitudes,…

  1. Increasing Reading Engagement in African American Boys

    ERIC Educational Resources Information Center

    Husband, Terry

    2014-01-01

    Much has been written concerning the challenges many teachers face in engaging African American males in reading practices. While much of this extant scholarship focuses on African American males at the pre-adolescent stage of development and beyond, little has been written regarding increasing reading engagement in African American boys in P-5…

  2. African Expressions in Hispano-American Literature.

    ERIC Educational Resources Information Center

    Coleman, Ben C.

    This revised version of a lecture on the relationship of African language and Hispano-American literature illustrates the historical influence of the African slave on representative literature and modern culture of the Caribbean Islands. Introductory remarks focus on the migratory patterns of the African slaves. The concept of negritude is then…

  3. An Introduction to West African Literature.

    ERIC Educational Resources Information Center

    Taiwo, Oladele

    Intended to provide help for those interested in studying West African literature, this book is divided into three parts. Part One provides background information: the various African oral traditions are discussed, related to the way of life of the people, and examined for the extent to which they form the basis of present West African literary…

  4. Empowering African genomics for infectious disease control.

    PubMed

    Folarin, Onikepe A; Happi, Anise N; Happi, Christian T

    2014-11-07

    At present, African scientists can only participate minimally in the genomics revolution that is transforming the understanding, surveillance and clinical treatment of infectious diseases. We discuss new initiatives to equip African scientists with knowledge of cutting-edge genomics tools, and build a sustainable critical mass of well-trained African infectious diseases genomics scientists.

  5. Heart failure in African Americans.

    PubMed

    Yancy, Clyde W

    2005-10-10

    The demographics of the United States are changing, and in the next few decades there will no longer be a racial/ethnic majority population. Increased awareness of cardiovascular disease (CVD) in special populations is warranted as these populations increase. Heart failure carries a substantial burden on those affected, particularly African Americans, who have a disproportionate burden of heart disease. Current treatments for heart failure include angiotensin-converting enzyme inhibitors, beta-blockers, angiotensin II-receptor antagonists, and vasodilating agents. This review discusses the unique characteristics of CVD in African Americans and addresses the need for targeted treatments to reduce the excess burden found in this population.

  6. The Role of the African Union in African Peacekeeping Operations

    DTIC Science & Technology

    2008-03-26

    Government in Sirte , Libya, on 9 September 1999. The AU was formed to address some of the issues identified during the analysis of the OAU PKOs. The...Establishment of the African Union The Sirte Declaration led to the establishment of the AU in 2002. One of the AU’s objectives was to enhance the security

  7. Viper NHEXS Program: A Viper Pilot Neck Health & Conditioning Guide

    DTIC Science & Technology

    2012-11-01

    Air Force Research Laboratory 711th Human Performance Wing School of Aerospace Medicine Aeromedical Research Dept 2510 Fifth St. Wright...units, which include the contralateral sternocleidomastoid, levator scapulae , scalenus, splenius capitis, and ipsilateral splenius capitis [6]. Neck

  8. African-American spirituality: a concept analysis.

    PubMed

    Newlin, Kelley; Knafl, Kathleen; Melkus, Gail D'Eramo

    2002-12-01

    Culturally competent care for African Americans requires sensitivity to spirituality as a component of the cultural context. To foster understanding, measurement, and delivery of the spiritual component of culturally competent care, this article presents an evolutionary concept analysis of African-American spirituality. The analysis is based on a sample of multidisciplinary research studies reflecting spirituality of African Americans. Findings indicate that African-American spirituality involves quintessential, internal, external, consoling, and transformative attributive dimensions. Findings are considered in relation to previous conceptual analyses of spirituality and suggest that defining attributes of African-American spirituality are both global and culturally prominent. Implications for practice and research are discussed.

  9. Cryptococcal meningitis in African children.

    PubMed

    Subramanyam, V R; Mtitimila, E; Hart, C A; Broadhead, R L

    1997-06-01

    Three cases of cryptococcal meningitis in Malawian children aged 6 weeks, 3 years and 9 years are described. Only 23 cases of cryptococcal meningitis in children have been described previously, but in children from Europe and the USA. These are therefore the first cases of cryptococcosis to be described in African children.

  10. Wellness among African American Counselors

    ERIC Educational Resources Information Center

    Day-Vines, Norma L.; Holcomb-McCoy, Cheryl

    2007-01-01

    Although there are various definitions of wellness, few conceptual definitions have addressed the contextual dimensions of wellness relative to African American counselors. The authors present an overview of generic models of wellness, discuss factors that both inhibit and promote wellness, offer some culture-specific models of wellness, and…

  11. African American Men in College

    ERIC Educational Resources Information Center

    Cuyjet, Michael J., Ed.

    2006-01-01

    This book is a much-needed resource that includes examples of real-world programs and activities to enhance academic success in the college environment for African American men. The examples are collected from a variety of institutions across the country. With contributions from leading practitioners and scholars in the field, this book explores…

  12. Improvisation in West African Musics.

    ERIC Educational Resources Information Center

    Locke, David

    1980-01-01

    Discussed is music of the sub-Sahara. Vocal, instrumental, and dance drumming from the Sudan Desert, the North Coast, East Horn, Central and West Africa, and contrapuntal yodeling of Pygmies is described. For African musicians, the ability to improvise, and creativity, are gifts from God. Includes selected readings and recordings. (KC)

  13. Developing anatomical terms in an African language.

    PubMed

    Madzimbamuto, Farai Daniel

    2012-02-23

    Clinical and technical information imparted in most African languages involves inexact terminology and code switching, so it lacks the explanatory power characterised by the English language. African languages are absent in the tertiary science education environment and forums where African scientists could present scientific material in the medium of African languages. This limits the development of African languages in the scientific domain. There has recently been a trend in several African languages to develop and intellectualise them, especially in the field of medical sciences. The ChiShona language is used to explore the ability of an African language to develop new terminology, to name the vertebral skeleton and describe it scientifically. It uses word compounding to demonstrate terminology development. ChiShona has similarities with several hundred other Bantu languages in East, Central and Southern Africa. Advancing this language can promote similar developments in others, making them more explanatory for the lay public and health professionals.

  14. Some African American Males' Perspectives on the Black Woman.

    ERIC Educational Resources Information Center

    Burrow, Rufus, Jr.

    1992-01-01

    Presents views of Frederick Douglass, W. E. B. Du Bois, Malcolm X, and James Hal Cone (African-American male leaders) toward African-American women in the United States. Discusses the role of African-American men in addressing and eradicating sexism in African-American churches and the African-American community. (SLD)

  15. The UCAR Africa Initiative: Enabling African Solutions to African Needs

    NASA Astrophysics Data System (ADS)

    Pandya, R.; Bruintjes, R.; Foote, B.; Heck, S.; Hermann, S.; Hoswell, L.; Konate, M.; Kucera, P.; Laing, A.; Lamptey, B.; Moncrieff, M.; Ramamurthy, M.; Roberts, R.; Spangler, T.; Traoré, A.; Yoksas, T.; Warner, T.

    2007-12-01

    The University Corporation for Atmospheric Research (UCAR) Africa Initiative (AI) is a coordinated effort aimed at building sustainable partnerships between UCAR and African institutions in order to pursue research and applications for the benefit of the African people. The initiative is based on four fundamental operating principles, concisely summarized by the overall philosophy of enabling African solutions to African needs. The four principles are: • Collaborate with African institutions • Focus on institutional capacity building and research support • Explore science research themes critical to Africa and important for the world • Leverage the research infrastructure in UCAR to add value These principles are realized in a set of pilot activities, chosen for their high probability of short-term results and ability to set the stage for longer-term collaboration. The three pilot activities are listed below. 1. A modest radar network and data-distribution system in Mali and Burkina Faso, including a data-sharing MOU between the Mail and Burkina Faso Weather Services. 2. A partnership among UCAR, the Ghana Meteorological Agency, and the Ghana university community to develop an operational Weather Research and Forecasting (WRF) model for West Africa. The output is used by researchers and operational forecasters in Africa. Model output is also part of a demonstration project that aims to allow humanitarian agencies to share geo-referenced information in Africa via a web portal. 3. A workshop in Ouagadougou, Burkina Faso from April 2-6, 2007, with the theme Improving Lives by Understanding Weather. The workshop, co-organized with Programme SAAGA and the Commité Permanent Inter-Etats de Lutte Contre la Sécheresse dans le Sahel (CILSS), included over 80 participants from 18 countries, and produced a set of recommendations for continued collaboration. Our presentation will provide an update of these pilot activities and point to future directions. Recognizing

  16. [Return of African sleeping sickness].

    PubMed

    Stingl, Peter

    2006-09-14

    At present there is a steady rise in African sleeping sickness (trypanosomiasis) transmitted by the Tsetse fly, and which if left untreated, is fatal. Thanks to more than so years of neglect by research, our therapeutic repertoire is limited to medications with a high level of toxicity. Both WHO and international aid organizations are pushing hard for the development of new, more efficient drugs that can be readily applied in the field.

  17. Genome-wide patterns of population structure and admixture in West Africans and African Americans.

    PubMed

    Bryc, Katarzyna; Auton, Adam; Nelson, Matthew R; Oksenberg, Jorge R; Hauser, Stephen L; Williams, Scott; Froment, Alain; Bodo, Jean-Marie; Wambebe, Charles; Tishkoff, Sarah A; Bustamante, Carlos D

    2010-01-12

    Quantifying patterns of population structure in Africans and African Americans illuminates the history of human populations and is critical for undertaking medical genomic studies on a global scale. To obtain a fine-scale genome-wide perspective of ancestry, we analyze Affymetrix GeneChip 500K genotype data from African Americans (n = 365) and individuals with ancestry from West Africa (n = 203 from 12 populations) and Europe (n = 400 from 42 countries). We find that population structure within the West African sample reflects primarily language and secondarily geographical distance, echoing the Bantu expansion. Among African Americans, analysis of genomic admixture by a principal component-based approach indicates that the median proportion of European ancestry is 18.5% (25th-75th percentiles: 11.6-27.7%), with very large variation among individuals. In the African-American sample as a whole, few autosomal regions showed exceptionally high or low mean African ancestry, but the X chromosome showed elevated levels of African ancestry, consistent with a sex-biased pattern of gene flow with an excess of European male and African female ancestry. We also find that genomic profiles of individual African Americans afford personalized ancestry reconstructions differentiating ancient vs. recent European and African ancestry. Finally, patterns of genetic similarity among inferred African segments of African-American genomes and genomes of contemporary African populations included in this study suggest African ancestry is most similar to non-Bantu Niger-Kordofanian-speaking populations, consistent with historical documents of the African Diaspora and trans-Atlantic slave trade.

  18. African-Centered Education: An Approach to Schooling for Social Justice for African American Students

    ERIC Educational Resources Information Center

    Marks, Jay B.; Tonso, Karen L.

    2006-01-01

    This essay argues that offering African American students an African-centered education is one way to promote social justice in public education. We begin with a summary of the inadequate educations offered to many African American students, and then use philosophical interpretations of equal educational opportunity to delineate the requirements…

  19. Investigating Instructional Practices of an African American Male Mathematics Teacher with Underachieving African American Male Students

    ERIC Educational Resources Information Center

    Muhammad, Rhonda K.

    2012-01-01

    This qualitative study examined the instructional practices of an experienced African American mathematics teacher to determine his perceived capabilities in augmenting academic proficiency for his African American male students. Provided in this descriptive case study are the lived experiences of an African American male teacher working to move…

  20. 75 FR 2844 - African Development Foundation, Board of Directors Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ...; ] AFRICAN DEVELOPMENT FOUNDATION African Development Foundation, Board of Directors Meeting Time: Tuesday, January 26, 2010, 8:30 a.m. to 1 p.m. Place: African Development Foundation, Conference Room, 1400...

  1. 75 FR 45600 - African Development Foundation, Board of Directors Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-03

    ...; ] AFRICAN DEVELOPMENT FOUNDATION African Development Foundation, Board of Directors Meeting Time: Tuesday, August 17, 2010, 8:30 a.m. to 1 p.m. Place: African Development Foundation, Conference Room, 1400...

  2. Race, health, and the African Diaspora.

    PubMed

    Spigner, Clarence

    Health inequalities exist throughout the African Diaspora and are viewed in this article as largely color-coded. In developed, developing, and undeveloped nations today, "racial" stratification is consistently reflected in an inability to provide adequate health regardless of national policy or ideology. For instance, African Americans experience less than adequate health care very similar to Blacks in Britain, in spite of each nations differing health systems. Latin America's Africana Negra communities experience poorer health similar to Blacks throughout the Caribbean. The African continent itself is arguably the poorest on earth. A common history of racism correlates with health disparities across the African Diaspora.

  3. African American girls and the challenges ahead.

    PubMed

    Rozie-Battle, Judith L

    2002-01-01

    The research on the psychosocial development of African American girls is limited. Information that is available focuses on teen pregnancy and health issues such as nutrition and physical activity. African American girls are facing challenges, including poverty, crime, poor self-esteem, and peer pressure. Despite some of the negative characteristics attributed to African American girls, many are achieving some success. Policy makers and service providers need to recognize the resiliency and unique needs of African American girls and develop services that ensure their needs are being fully met.

  4. Rhinoplasty in the African-American patient.

    PubMed

    Rohrich, Rod J; Muzaffar, Arshad R

    2003-03-01

    Because of the increasing popularity of rhinoplasty in the African-American patient, we delineate how a rhinoplasty surgeon can perform this challenging technique to obtain uniform and consistent results. First, we address how one can appreciate and analyze the various aesthetic concepts of beauty and the unique anatomic characteristics of the African-American nose. Second, we present a pragmatic, systematic analysis of the African-American nose. Last, we describe the techniques consistently used to modify the African-American nose while achieving or maintaining facial harmony using the open approach to rhinoplasty. Specific case analyses are presented to demonstrate utilization of the technique.

  5. The African diaspora: history, adaptation and health.

    PubMed

    Rotimi, Charles N; Tekola-Ayele, Fasil; Baker, Jennifer L; Shriner, Daniel

    2016-12-01

    The trans-Atlantic slave trade brought millions of Africans to the New World. Advances in genomics are providing novel insights into the history and health of Africans and the diasporan populations. Recent examples reviewed here include the unraveling of substantial hunter-gatherer and 'Eurasian' admixtures across sub-Saharan Africa, expanding our understanding of ancestral African genetics; the global ubiquity of mixed ancestry; the revealing of African ancestry in Latin Americans that likely derived from the slave trade; and understanding of the ancestral backgrounds of APOL1 and LPL found to influence kidney disease and lipid levels, respectively, providing specific insights into disease etiology and health disparities.

  6. Gentle Africanized bees on an oceanic island.

    PubMed

    Rivera-Marchand, Bert; Oskay, Devrim; Giray, Tugrul

    2012-11-01

    Oceanic islands have reduced resources and natural enemies and potentially affect life history traits of arriving organisms. Among the most spectacular invasions in the Western hemisphere is that of the Africanized honeybee. We hypothesized that in the oceanic island Puerto Rico, Africanized bees will exhibit differences from the mainland population such as for defensiveness and other linked traits. We evaluated the extent of Africanization through three typical Africanized traits: wing size, defensive behavior, and resistance to Varroa destructor mites. All sampled colonies were Africanized by maternal descent, with over 65% presence of European alleles at the S-3 nuclear locus. In two assays evaluating defense, Puerto Rican bees showed low defensiveness similar to European bees. In morphology and resistance to mites, Africanized bees from Puerto Rico are similar to other Africanized bees. In behavioral assays on mechanisms of resistance to Varroa, we directly observed that Puerto Rican Africanized bees groomed-off and bit the mites as been observed in other studies. In no other location, Africanized bees have reduced defensiveness while retaining typical traits such as wing size and mite resistance. This mosaic of traits that has resulted during the invasion of an oceanic island has implications for behavior, evolution, and agriculture.

  7. Gentle Africanized bees on an oceanic island

    PubMed Central

    Rivera-Marchand, Bert; Oskay, Devrim; Giray, Tugrul

    2012-01-01

    Oceanic islands have reduced resources and natural enemies and potentially affect life history traits of arriving organisms. Among the most spectacular invasions in the Western hemisphere is that of the Africanized honeybee. We hypothesized that in the oceanic island Puerto Rico, Africanized bees will exhibit differences from the mainland population such as for defensiveness and other linked traits. We evaluated the extent of Africanization through three typical Africanized traits: wing size, defensive behavior, and resistance to Varroa destructor mites. All sampled colonies were Africanized by maternal descent, with over 65% presence of European alleles at the S-3 nuclear locus. In two assays evaluating defense, Puerto Rican bees showed low defensiveness similar to European bees. In morphology and resistance to mites, Africanized bees from Puerto Rico are similar to other Africanized bees. In behavioral assays on mechanisms of resistance to Varroa, we directly observed that Puerto Rican Africanized bees groomed-off and bit the mites as been observed in other studies. In no other location, Africanized bees have reduced defensiveness while retaining typical traits such as wing size and mite resistance. This mosaic of traits that has resulted during the invasion of an oceanic island has implications for behavior, evolution, and agriculture. PMID:23144660

  8. Effect of freezing plasma at -20°C for 2 weeks on prothrombin time, activated partial thromboplastin time, dilute Russell viper venom time, activated protein C resistance, and D-dimer levels.

    PubMed

    Foshat, Michelle; Bates, Stephanie; Russo, Wendy; Huerta, Araceli; Albright, Kathleen; Giddings, Karen; Indrikovs, Alexander; Qian, You-Wen

    2015-01-01

    To assess the impact of preanalytical variables of time and temperature on prothrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russell viper venom time (DRVVT), activated protein C resistance (APCR), and d-dimer, samples from 23 healthy individuals and 18 patients having coagulopathy with known abnormal PT and aPTT were collected. Plasma from each individual was separately pooled and aliquoted; the first 2 aliquots were stored at room temperature then analyzed at 2 hours (baseline) and 4 hours postcollection. The remaining aliquots were stored at -20°C and thawed for analysis at 48 hours, 1, and 2 weeks. In both healthy participants and participants with coagulopathy, PT, aPTT, APCR, DRVVT, and D-dimer had no significant changes at 4 and 48 hours, and 1 and 2 weeks postcollection compared to baseline, or the changes were less than 10%. The results indicate PT, aPTT, DRVVT, APCR, and d-dimer can be stored for 2 weeks at -20°C without compromising clinical interpretation in both healthy individuals and individuals with coagulopathy. Increasing storage time will facilitate sample processing from off-site clinics.

  9. Inhibition of the hemorrhagic and proteolytic activities of Lansberg's hognose pit viper (Porthidium lansbergii hutmanni) venom by opossum (Didelphis marsupialis) serum: isolation of Didelphis marsupialis 0.15Dm fraction on DEAE-cellulose chromatography.

    PubMed

    Pineda, María E; Girón, María E; Estrella, Amalid; Sánchez, Elda E; Aguilar, Irma; Fernandez, Irma; Vargas, Alba M; Scannone, Héctor; Rodríguez-Acosta, Alexis

    2008-01-01

    Earlier studies have revealed the ability of sera from several mammals to neutralize the toxic effects of snake venom. The Venezuelan opossum (Didelphis marsupialis) is one that has been found to inhibit hemorrhagic and proteolytic activities of venoms from many species of snakes. In this article it is shown that the opossum sera and its 0.15DM fraction were able to completely neutralize both hemorrhagic and hydrolysis (proteolysis) of casein effects induced by venom of the Lansberg's hognose pit viper (Porthidium lansbergii hutmanni). We have used DEAE-cellulose ion exchange chromatography to collect protein fractions from D. marsupialis sera which were able to defend mice from the lethal effects of P.l. hutmanni venom. The fractions separated were homogeneous by conventional electrophoresis using SDS-PAGE. The protein bands obtained contained molecular weights of approximately 6 to 220 kDa. These results revealed the presence of proteases inhibitors in the opossum sera fractions and the inhibition of venom activity by opossum sera suggesting a reciprocal adaptation at the molecular level.

  10. Expression of mRNAs coding for VAP1/crotastatin-like metalloproteases in the venom glands of three South American pit vipers assessed by quantitative real-time PCR.

    PubMed

    Tavares, N A C; Correia, J M; Guarnieri, M C; Lima-Filho, J L; Prieto-da-Silva, A R B; Rádis-Baptista, G

    2008-12-15

    Snake venom metalloproteases encompass a large family of toxins, with approximately 200 members already catalogued, which exhibit a diversity of structures and biological functions. From this relatively large number, only a dozen examples of apoptosis-inducing metalloproteases, like VAP1 and 2 from the venom of Crotalus atrox, are known. Since most VAP1-like toxins ever characterized were purified from the venom of Viperidae species inhabiting diverse places on earth, we investigate the expression of VAP-like metalloproteases in the venom gland of three representative pit vipers of the Brazilian territory. By molecular cloning and quantitative real-time polymerase chain reaction, using as calibrator gene the Crotalus durissus terrificus homolog of VAP1, named crotastatin, it is reported here that VAP1/crotastatin-like homologues in the venom gland of Bothrops atrox, C. d. cascavella and Lachesis m. rhombeata are expressed at different levels. Hence, batroxstatins, the crotastatin-like precursors from B. atrox, are expressed 87 times more than crotastatin-1, from C. d. cascavella, and 7.5-fold that lachestatins, from L. m. rhombeata. Moreover, in silico structural analysis of amino acid sequences indicates that batroxstatin-2, crotastatins and lachestatin-1 and -2 which share the archetypal motifs and metal- binding sites of VAP1, are subgrouped in a branch that comprises some apoptosis-inducing toxins.

  11. Conflict and human African trypanosomiasis.

    PubMed

    Berrang-Ford, Lea; Lundine, Jamie; Breau, Sebastien

    2011-02-01

    Human African Trypanosomiasis (HAT) has reemerged in sub-Saharan Africa as a disease of major public health importance. The success of HAT elimination in sub-Saharan Africa is subject to the feasibility of controlling, eliminating, or mitigating the determinants of incidence in affected countries. Conflict has been widely recognized and cited as a contributing factor to the resurgence of HAT in many countries, as well as to continuing HAT incidence in politically unstable and resource-poor regions. Despite extensive anecdotal and qualitative recognition of the role of conflict, there has been no quantitative research of this topic at the population level in affected African countries. We characterize the qualitative and quantitative associations between HAT incidence and conflict-related processes in HAT-affected African countries over the past 30 years. HAT and conflict-related data were collected for 35 affected countries in sub-Saharan Africa for the years 1976-2004. Descriptive and univariate inferential statistics, as well as negative binomial regression modeling, are used to assess the associations between HAT and conflict. A space-time scan statistic is used to identify significant incidence clusters. Clusters of HAT incidence over the past 30 years have predominantly coincided with periods of conflict or socio-political instability. HAT cases occurred significantly more often in countries and during years with conflict, high political terror, and internationalized civil war. The results indicate a lag period between the start of conflict events and a peak in incidence of approximately 10 years. We recommend explicit consideration and quantification of socio-political measures such as conflict and terror indices in GIS (Geographic Information Systems)-based risk assessments for HAT policy and intervention.

  12. Hydrogenotrophic microbiota distinguish native Africans from African and European Americans.

    PubMed

    Nava, Gerardo M; Carbonero, Franck; Ou, Junhai; Benefiel, Ann C; O'Keefe, Stephen J; Gaskins, H Rex

    2012-06-01

    Reduced susceptibility to sporadic colorectal cancer in native Africans (NA) is correlated with low consumption of animal products and greater microbial production of colonic methane. In this context, two hydrogenotrophic microbial groups are of interest, methanogenic Archaea (MA) utilizing H2 to produce methane and sulfate-reducing bacteria (SRB) generating hydrogen sulfide, which has been linked with chronic inflammatory disorders of the colon. In the present study, stool samples from NA, consuming a diet high in resistant starch and low in animal products, and from African Americans (AA) and European Americans (EA), both consuming a typical Western diet, were examined for genetic diversity and structure of Archaea, MA and SRB communities. In general, a greater proportion of NA than AA and EA harboured the full range of targeted hydrogenotrophic groups. Terminal restriction fragment length polymorphism analysis of 16S rRNA genes and specific functional genes, combined with multivariate statistical analyses, revealed that NA harboured more diverse and different Archaea and MA populations than AA and EA. Also, NA harboured significantly distinct SRB populations compared with AA and EA. Taken together, these data are consistent with diet selecting for distinct hydrogenotrophic microbiota.

  13. France: Africans and the French Revolution.

    ERIC Educational Resources Information Center

    Fatunde, Tunde

    1989-01-01

    The French Revolution had profound and long-term effects for Africans, both in Africa and throughout the Western hemisphere. Revolutionary leaders not only opposed the emancipation of slaves in French territories but supported an intensified slave trade, sparking numerous rebellions. French exploitation of Africans extended well into the twentieth…

  14. African (Black) Psychology: Issues and Synthesis.

    ERIC Educational Resources Information Center

    Baldwin, Joseph A.

    1986-01-01

    Reviews the recent attempts of Black psychologists and social scientists to formulate a conceptual-operational framework for the study of psychological phenomena as they bear on the cultural-survival conditions of Black-African people. Outlines issues and problems in the attempt to define African (Black) psychology and discusses its relation to…

  15. Kunta Kinte's Struggle to be African

    ERIC Educational Resources Information Center

    Courlander, Harold

    1986-01-01

    This article reveals the differences between the character Kunta Kinte and the historical record concerning African males in the preslavery period. Kunta's non-African behaviors include displays of blind anger and rage, prudishness, and actions unknown in his Mandinka culture. These represent the many misrepresentations and ambiguities in Alex…

  16. Multicultural Curriculum: African American Children's Literature.

    ERIC Educational Resources Information Center

    Harris, Violet J.

    1991-01-01

    Traces and analyzes the history of African American children's literature defined as "culturally conscious," an authentic body of literature written about and for African American children. Discusses the current status of this literature and indicates a change in focus in the last century. Authors' perspectives, and the implications for…

  17. African American Undergraduates and the Academic Library

    ERIC Educational Resources Information Center

    Whitmire, Ethelene

    2006-01-01

    This study examines the academic library experiences of African American undergraduates attending a research university in the Midwest. Data collection techniques included questionnaires and ethnographic observations. The results indicated that African American undergraduates are using the academic library primarily to read and to study with their…

  18. African Education and Globalization: Critical Perspectives

    ERIC Educational Resources Information Center

    Abdi, Ali A., Ed.; Puplampu, Korbla P., Ed.; Dei, George J. Sefa, Ed.

    2006-01-01

    Containing both theoretical discussions of globalization and specific case analyses of individual African countries, this collection of essays examines the intersections of African education and globalization with multiple analytical and geographical emphases and intentions. The 11 essays critically analyze the issues from historical, cultural,…

  19. Smoking Cessation in African-Americans.

    ERIC Educational Resources Information Center

    Ahluwalia, Jasjit S.

    1996-01-01

    Because the smoking behavior of African Americans differs considerably from that of other groups, researchers examined differences between African Americans who did and did not use the nicotine patch as an adjunct to counseling and education for smoking cessation. Results indicated the nicotine patch significantly improved six-month cessation…

  20. Genetics Home Reference: African iron overload

    MedlinePlus

    ... of a genetic condition? Genetic and Rare Diseases Information Center Frequency African iron overload is common in rural areas of central and ... more about the gene associated with African iron overload SLC40A1 Related Information What is a gene? What is a gene ...

  1. Cultural Expressions of the African American Child.

    ERIC Educational Resources Information Center

    Akbar, Na'im

    Interpretations of the differences between the African American child and the Caucasian child in North America follow two major trends. In one the differences in the African American child are viewed as deviance from the Euro-American norm and therefore inferior or pathological. In the other, the differences are viewed as deviant but adaptive…

  2. A Mirror Image African American Student Reflections

    ERIC Educational Resources Information Center

    Cannon Dawson, Candice

    2012-01-01

    This dissertation is a narrative inquiry research project that focuses on the collegiate experiences of African American students at both historically black colleges and universities (HBCUs) and predominantly white institutions (PWIs). I look at how African American college students who engage in race or culturally specific activities, the degree…

  3. Syntactic Variation in West African English.

    ERIC Educational Resources Information Center

    Bamiro, Edmund O.

    1995-01-01

    Describes syntactic variation in West African English with examples from West African English literature and identifies and describes subjectless sentences, deletion of the -ly morpheme in manner adjuncts, omission of function words, reduplication, tag questions, substitution of prepositions in idiomatic usage, and focus constructions. (53…

  4. Experiences of African American College Graduates

    ERIC Educational Resources Information Center

    Green, Aundria Chephan

    2014-01-01

    The purpose of this study was to explore the reasons that African-American alumni from a historically Black university (HBCU) and a predominantly White university (PWI) chose to attend, remain in, and graduate from college. The central research question was how do African Americans describe their college experiences? The secondary research…

  5. Hidden Education among African Americans during Slavery

    ERIC Educational Resources Information Center

    Gundaker, Grey

    2007-01-01

    Background/Context: Historical studies examine aspects of African American education in and out of school in detail (Woodson 1915, 1933, Bullock 1970, Anderson 1988, Morris 1982, Rachal 1986, Rose 1964, Webber 1978, Williams 2005). Scholars of African American literacy have noted ways that education intersects other arenas such as religion and…

  6. African Americans in the Early Republic.

    ERIC Educational Resources Information Center

    Nash, Gary B.

    2000-01-01

    Discusses five topics on African Americans that are essential to studying United States History in the years between 1760 and 1830: (1) African Americans in the Revolutionary War ; (2) the rise of free black communities; (3) early abolitionism; (4) the spread of slavery; and (5) black resistance to slavery. (CMK)

  7. A Reader's Guide to African Literature.

    ERIC Educational Resources Information Center

    Zell, Hans M., Ed.; Silver, Helene, Ed.

    This annotated bibliography lists 820 literary works by black African authors south of the Sahara writing in English and in French. Reference material, critical works, and anthologies (many by non-Africans) are also included. The bibliography--excluding reference and critical works and anthologies--is divided into two sections. "Writings in…

  8. Precolonial African History. AHA Pamphlets, 501.

    ERIC Educational Resources Information Center

    Curtin, Philip D.

    This pamphlet surveys western historiography of precolonial Africa. Prior to World War II, African history emphasized the European role in Africa, relegating African history before European colonization to minor importance. Only after the increase in university enrollments and funding in the 1960's did opportunities for innovative research and new…

  9. New data on African health professionals abroad

    PubMed Central

    Clemens, Michael A; Pettersson, Gunilla

    2008-01-01

    Background The migration of doctors and nurses from Africa to developed countries has raised fears of an African medical brain drain. But empirical research on the causes and effects of the phenomenon has been hampered by a lack of systematic data on the extent of African health workers' international movements. Methods We use destination-country census data to estimate the number of African-born doctors and professional nurses working abroad in a developed country circa 2000, and compare this to the stocks of these workers in each country of origin. Results Approximately 65,000 African-born physicians and 70,000 African-born professional nurses were working overseas in a developed country in the year 2000. This represents about one fifth of African-born physicians in the world, and about one tenth of African-born professional nurses. The fraction of health professionals abroad varies enormously across African countries, from 1% to over 70% according to the occupation and country. Conclusion These numbers are the first standardized, systematic, occupation-specific measure of skilled professionals working in developed countries and born in a large number of developing countries. PMID:18186916

  10. Depression, Sociocultural Factors, and African American Women

    ERIC Educational Resources Information Center

    Hunn, Vanessa Lynn; Craig, Carlton David

    2009-01-01

    The authors discuss depression in African American women from a sociocultural perspective, including aspects of oppression and racism that affect symptom manifestation. The authors highlight John Henryism as a coping mechanism, the history and continuing role of the African American church as a safe haven, and strategies for culturally competent…

  11. An African Perspective on Human Rights.

    ERIC Educational Resources Information Center

    Shiman, David

    1992-01-01

    Presents a series of classroom activities comparing differing views of human rights in the United Nations Universal Declaration of Human Rights and the African Charter on Human and People's Rights. Includes excerpts from the African Charter on Human and People's Rights and the full text of the Universal Declaration of Human Rights. (CFR)

  12. Prostate Cancer Genetics in African Americans

    DTIC Science & Technology

    2015-11-01

    AWARD NUMBER: W81XWH-11-1-0566 TITLE: Prostate Cancer Genetics in African Americans PRINCIPAL INVESTIGATOR: Henry T. Lynch, MD CONTRACTING...W81XWH-11-1-0566 November 2015 Final 15Aug2011 - 14Aug2015 Prostate Cancer Genetics in African Americans Henry T. Lynch Nothing listed 36

  13. South African Students' Views of the Universe.

    ERIC Educational Resources Information Center

    Lemmer, M.; Lemmer, T. N.; Smit, J. J. A.

    2003-01-01

    Investigates perceptions of the universe of (n=232) first-year physics students from two South African universities. Compared results with Aristotelian and Newtonian views as well as with those of children as revealed in a literature survey. Results also showed that a statistically significant larger number of African than European students have…

  14. Supporting Change: Working with South African Universities.

    ERIC Educational Resources Information Center

    Moran, Anne D.; Volmink, John

    1986-01-01

    University and pre-university education in South Africa is briefly described, along with areas where U.S. universities can assist South African organizations working to promote equal access to quality education. Three basic areas are explored: financial aid for South African students; manpower support to help in tutorials and academic research;…

  15. British African Caribbean Women and Depression

    ERIC Educational Resources Information Center

    Adkison-Bradley, Carla; Maynard, Donna; Johnson, Phillip; Carter, Stephaney

    2009-01-01

    Depression is a common condition among women in the United Kingdom. However, little is known about the context of depression among British African Caribbean women. This article offers a preliminary discussion regarding issues and information pertaining to depression among British African Caribbean women. Characteristics and symptoms of depression…

  16. The Process of Africanizing the Social Studies.

    ERIC Educational Resources Information Center

    Merryfield, Merry M.; Tlou, Josiah

    1995-01-01

    Investigates social studies curriculum reform in Botswana, Kenya, Malawi, Nigeria, and Zimbabwe. Reports on each country contain a brief overview of the historical situation and current syllabus, and a discussion of the ongoing "Africanization" process. Concludes with a definition of "Africanization," its purpose, and…

  17. Improving African American Achievement in Geometry Honors

    ERIC Educational Resources Information Center

    Mims, Adrian B.

    2010-01-01

    This case study evaluated the significance of implementing an enrichment mathematics course during the summer to rising African American ninth graders entitled, "Geometry Honors Preview." In the past, 60 to 70 percent of African American students in this school district had withdrawn from Geometry Honors by the second academic quarter. This study…

  18. A Reevaluation of African Education: Woodson Revisited.

    ERIC Educational Resources Information Center

    Okafor, Victor Oguejiofor

    1992-01-01

    Reviews the ideas of C. G. Woodson (1875-1950) about the inappropriate education received by African Americans. Although Woodson's book, "The Mis-Education of the Negro," was written in 1933, his diagnosis of the state of the African-American community appears to hold up well today. (SLD)

  19. African Americans and World War II.

    ERIC Educational Resources Information Center

    Kersten, Andrew E.

    2002-01-01

    Focuses on the experience of African Americans during World War II on the homefront and in the armed forces. States that African Americans not only fought fascism overseas but also apartheid in the United States, also known as the "Double V." (CMK)

  20. Prostate cancer in men of African origin.

    PubMed

    McGinley, Kathleen F; Tay, Kae Jack; Moul, Judd W

    2016-02-01

    Men of African origin are disproportionately affected by prostate cancer: prostate cancer incidence is highest among men of African origin in the USA, prostate cancer mortality is highest among men of African origin in the Caribbean, and tumour stage and grade at diagnosis are highest among men in sub-Saharan Africa. Socioeconomic, educational, cultural, and genetic factors, as well as variations in care delivery and treatment selection, contribute to this cancer disparity. Emerging data on single-nucleotide-polymorphism patterns, epigenetic changes, and variations in fusion-gene products among men of African origin add to the understanding of genetic differences underlying this disease. On the diagnosis of prostate cancer, when all treatment options are available, men of African origin are more likely to choose radiation therapy or to receive no definitive treatment than white men. Among men of African origin undergoing surgery, increased rates of biochemical recurrence have been identified. Understanding differences in the cancer-survivorship experience and quality-of-life outcomes among men of African origin are critical to appropriately counsel patients and improve cultural sensitivity. Efforts to curtail prostate cancer screening will likely affect men of African origin disproportionately and widen the racial disparity of disease.

  1. The TG/HDL-C ratio does not predict insulin resistance in overweight women of African descent: a study of South African, African American and West African women.

    PubMed

    Knight, Michael G; Goedecke, Julia H; Ricks, Madia; Evans, Juliet; Levitt, Naomi S; Tulloch-Reid, Marshall K; Sumner, Anne E

    2011-01-01

    Women of African descent have a high prevalence of diseases caused by insulin resistance. To positively impact cardiometabolic health in Black women, effective screening tests for insulin resistance must be identified. Recently, the TG/HDL-C ratio has been recommended as a tool to predict insulin resistance in overweight people. While the ratio predicts insulin resistance in White women, it is ineffective in African American women. As there are no data for African women, we tested the ability of the TG/HDL-C ratio to predict insulin resistance in Black women from South Africa, West Africa and the United States. For comparison, the ratio was also tested in White women from South Africa. Participants were 801 women (157 Black South African, 382 African American, 119 West African, 143 White South African, age 36 +/- 9y [mean +/- SD]). Standardized scores were created from log-transformed homeostasis model assessment-insulin resistance values from each population. Participants in the upper third of their population distribution were classified as insulin-resistant. To predict insulin resistance by the TC/HDL-C ratio, area under the receiver operating characteristic (AUC-ROC) curve was used and criteria were: 0.50 for no discrimination and > or = 0.70 for acceptable. Seventy-one percent of the Black women were overweight vs 51% of White women (P<.01). In overweight White women, AUC-ROC curve for prediction of insulin resistance by TG/HDL-C was 0.76 +/- 0.06, but below the 0.70 threshold in each group of overweight Black women (Black South African: 0.64 +/- 0.06, African American: 0.66 +/- 0.03, and West African: 0.63 +/- 0.07). Therefore, TG/HDL-C does not predict insulin resistance in overweight African American women and this investigation extends that finding to overweight Black South African and West African women. Resources to identify effective markers of insulin resistance are needed to improve cardiometabolic health in women of African descent.

  2. The extent of burning in African savanna

    NASA Technical Reports Server (NTRS)

    Cahoon, D. R. JR.; Levine, J. S.; Cofer, W. R. Iii; Stocks, B. J.

    1994-01-01

    The temporal and spatial distribution of African savanna grassland fires has been examined, and the areal extent of these fires has been estimated for the subequatorial African continent. African savanna fires have been investigated using remote sensing techniques and imagery collected by low-light sensors on Defense Meteorological Satellite Program (DMSP) satellites and by the Advanced Very High Resolution Radiometer (AVHRR) which is aboard polar orbiting National Oceanic and Atmospheric Administration (NOAA) satellites. DMSP imagery has been used to map the evolution of savanna burning over all of the African continent and the analysis of AVHRR imagery has been used to estimate the areal extent of the burning in the southern hemispheric African savannas. The work presented primarily reflects the analysiscompleted for the year 1987. However, comparisons have been made with other years and the representativeness of the 1987 analysis is discussed.

  3. Intimate partner violence in African American women.

    PubMed

    Campbell, Doris Williams; Sharps, Phyllis W; Gary, Faye A; Campbell, Jacquelyn C; Lopez, Loretta M

    2002-01-01

    Violence against African American women, specifically intimate partner abuse, has a significant impact on their health and well being. Intimate partner femicide and near fatal intimate partner femicide are the major causes of premature death and disabling injuries for African American women. Yet, despite this, there is a paucity of research and interventions specific and culturally relevant for these women. This article focuses on issues relevant to intimate partner violence and abuse against African American women by examining existing empirical studies of prevalence and health outcomes of intimate partner violence against women in general, plus what limited research there is about African American women, specifically. It includes a discussion of specific recommendations for research, practice, education, and policy to reduce and prevent intimate partner violence against African American women.

  4. African Americans and the medical establishment.

    PubMed

    Smith, C

    1999-09-01

    The African American community's response to the AIDS epidemic has reflected the profound mistrust of the medical establishment which many African Americans feel. Among African Americans, the belief that the epidemic originated in a genocidal plot is widespread. It is thought that organized medicine has been significantly involved in this plot. If we look at African Americans' historical relationship to the medical establishment from the era of slavery to the recent past, the suspicious attitudes which make such beliefs possible can be seen as an intelligible response to a new disease which disproportionately affects African Americans. Successful medical and public health responses to the epidemic have depended and will continue to depend upon overcoming the historical legacy of suspicion and gaining the trust of the community.

  5. HMO employment and African-American physicians.

    PubMed Central

    Briscoe, Forrest; Konrad, Thomas R.

    2006-01-01

    OBJECTIVES: To assess the level and determinants of African-American physicians' employment in health maintenance organizations (HMOs), particularly early in their careers. METHODS: We analyzed data from the 1991 and 1996 Young Physicians Surveys to assess racial differences in the likelihood of HMO employment (n = 3,705). Using multinomial logistic regression, we evaluated four explanations for an observed relationship between African-American physicians and HMO employment: human capital stratification among organizations, race-based affinity between physicians and patients, financial constraints due to debt burden, and different organizational hiring practices. Using binomial logistic regression, we also evaluated differences in the odds of being turned down for a prior practice position, of subsequently leaving the current practice organization and of later having career doubts. RESULTS: Without any controls, African-American physicians were 4.52 times more likely to practice in HMOs than Caucasian physicians. After controlling for human capital stratification, racial concordance and financial constraints, African-American physicians remained 2.48 times more likely to practice in HMOs than Caucasian physicians. In addition, 19.2% of African-American physicians in HMOs reported being turned down for another job, far more than any other racial/ethnic group in the HMO setting and any racial/ethnic group, including African-American physicians in the non-HMO setting (including all other practice locations). Five years later, those same African-American physicians from HMOs also reported significantly more turnover (7.50 times more likely than non-HMO African-American physicians to leave their current practice) and doubt about their careers (2.17 times more likely than non-HMO African-American physicians to express serious career doubts). CONCLUSIONS: African-American physicians were disproportionately hired into HMO settings, impacting their subsequent careers. PMID

  6. The African Folktale. An Instructional Unit for Seventh Grade English.

    ERIC Educational Resources Information Center

    Dobbs, Sherry

    The document presents a 3-week seventh grade English unit on the African folktale. The guide is one of a number of products developed by a summer workshop for teachers on African curriculum development. The objectives are to help students develop respect for African cultures and lifestyles, compare values of African and American ethnic…

  7. School Counseling for African American Adolescents: The Alfred Adler Approach

    ERIC Educational Resources Information Center

    Sapp, Marty

    2010-01-01

    This article discusses how Adlerian counseling can be used as a form of school counseling for African American adolescents. Moreover, school counseling for African American adolescents is discussed within the context of African American culture. Due to the strength-based nature of Adlerian approach, it can capitalize on African American…

  8. Towards an Africological Pedagogical Approach to African Civilization.

    ERIC Educational Resources Information Center

    Okafor, Victor Oguejiofor

    1996-01-01

    Presents a case study of controversies related to African studies and makes the case for an Africological pedagogical approach to African Civilization. The title "African Civilization" reflects the African place in the whole of world civilization even though that place is itself a multiple entity. (SLD)

  9. African American cancer patients' pain experience.

    PubMed

    Im, Eun-Ok; Lim, Hyun-Ju; Clark, Maresha; Chee, Wonshik

    2008-01-01

    Although very little is known about African American cancer patients' pain experience, a few studies have indicated that their cancer pain experience is unique and somewhat different from that of other ethnic groups. The purpose of the study reported in this article was to explore African American cancer patients' pain experience using an online forum. This study was a qualitative online forum designed from a feminist perspective and conducted among 11 African American cancer patients who were recruited through both Internet and real settings. Nine online forum topics were used to administer the 6-month online forum, and the data were analyzed using thematic analysis. Four themes emerged through the data analysis process. First, participants viewed cancer as a challenge in life that they should fight against. Second, cancer pain was differentiated from ordinary pain because cancer was stigmatized in their culture. Third, participants viewed that African Americans, especially women, were culturally raised to be strong, and this African American cultural heritage inhibited cancer patients from expressing pain and seeking help for pain management. Finally, the findings indicated certain changes in perspectives among African American cancer patients during the disease process, which might make them tolerate pain through praying to God and reading the Bible. Based on the findings, we suggest further studies among diverse groups of African American cancer patients, with a focus on cultural attitudes toward cancer pain and influences of family on cancer pain experience.

  10. Enslaved Africans and doctors in South Carolina.

    PubMed

    Goodson, Martia Graham

    2003-03-01

    This interpretation of the relationship between enslavement and American medicine in 19th century South Carolina reveals the intimacy that existed between Africans enslaved in that state and the doctors who practiced and taught there. Enslaved Africans were resourceful and reliable medical figures in the slave community. Their knowledge of medical botany permeated the slave quarters and plantation hospitals and was appropriated into southern medical knowledge. The trajectories of the careers of three South Carolina physicians are tied to their practice around and on the enslaved. The beginnings of gynecological surgery are linked to 1840s experimentation on enslaved African women performed by one of them.

  11. Two incidents of venomous snakebite on juvenile blue and Sykes monkeys (Cercopithecus mitis stuhlmanni and C. m. albogularis).

    PubMed

    Foerster, Steffen

    2008-10-01

    Although rarely observed, predation is thought to be an important factor in the evolution of primate life histories and behavior. Here I describe two incidents of snake predation on Cercopithecus mitis guenons from Kenya. The first case involved a juvenile blue monkey (Cercopithecus mitis stuhlmanni) in the Kakamega Forest, which died following a bite by a Gaboon viper (Bitis gabonica gabonica). The snake's attempts to ingest its prey were unsuccessful. In the second incident, a juvenile Sykes monkey (Cercopithecus mitis albogularis) at Gede Ruins National Monument died suddenly after suffering symptoms that are characteristic of bites inflicted by black mambas (Dendroaspis polylepis). In both cases circumstantial evidence suggests that attacks occurred during extended play sessions in dense vegetation on or near the ground. If so, the observations support the hypothesis that play may be a costly activity.

  12. Henipavirus RNA in African Bats

    PubMed Central

    Gloza-Rausch, Florian; Seebens, Antje; Annan, Augustina; Ipsen, Anne; Kruppa, Thomas; Müller, Marcel A.; Kalko, Elisabeth K. V.; Adu-Sarkodie, Yaw; Oppong, Samuel; Drosten, Christian

    2009-01-01

    Background Henipaviruses (Hendra and Nipah virus) are highly pathogenic members of the family Paramyxoviridae. Fruit-eating bats of the Pteropus genus have been suggested as their natural reservoir. Human Henipavirus infections have been reported in a region extending from Australia via Malaysia into Bangladesh, compatible with the geographic range of Pteropus. These bats do not occur in continental Africa, but a whole range of other fruit bats is encountered. One of the most abundant is Eidolon helvum, the African Straw-coloured fruit bat. Methodology/Principal Findings Feces from E. helvum roosting in an urban setting in Kumasi/Ghana were tested for Henipavirus RNA. Sequences of three novel viruses in phylogenetic relationship to known Henipaviruses were detected. Virus RNA concentrations in feces were low. Conclusions/Significance The finding of novel putative Henipaviruses outside Australia and Asia contributes a significant extension of the region of potential endemicity of one of the most pathogenic virus genera known in humans. PMID:19636378

  13. Enhancing the African bioethics initiative

    PubMed Central

    Ogundiran, Temidayo O

    2004-01-01

    Background Medical ethics has existed since the time of Hippocrates. However, formal training in bioethics did not become established until a few decades ago. Bioethics has gained a strong foothold in health sciences in the developed world, especially in Europe and North America. The situation is quite different in many developing countries. In most African countries, bioethics – as established and practiced today in the west- is either non-existent or is rudimentary. Discussion Though bioethics has come of age in the developed and some developing countries, it is still largely "foreign" to most African countries. In some parts of Africa, some bioethics conferences have been held in the past decade to create research ethics awareness and ensure conformity to international guidelines for research with human participants. This idea has arisen in recognition of the genuine need to develop capacity for reviewing the ethics of research in Africa. It is also a condition required by external sponsors of collaborative research in Africa. The awareness and interest that these conferences have aroused need to be further strengthened and extended beyond research ethics to clinical practice. By and large, bioethics education in schools that train doctors and other health care providers is the hook that anchors both research ethics and clinical ethics. Summary This communication reviews the current situation of bioethics in Africa as it applies to research ethics workshops and proposes that in spite of the present efforts to integrate ethics into biomedical research in Africa, much still needs to be done to accomplish this. A more comprehensive approach to bioethics with an all-inclusive benefit is to incorporate formal ethics education into health training institutions in Africa. PMID:15488145

  14. Pre-clinical and preliminary dose-finding and safety studies to identify candidate antivenoms for treatment of envenoming by saw-scaled or carpet vipers (Echis ocellatus) in northern Nigeria.

    PubMed

    Abubakar, S B; Abubakar, I S; Habib, A G; Nasidi, A; Durfa, N; Yusuf, P O; Larnyang, S; Garnvwa, J; Sokomba, E; Salako, L; Laing, G D; Theakston, R D G; Juszczak, E; Alder, N; Warrell, D A

    2010-04-01

    The aim of this study was to identify candidate antivenoms with specific activity against the venom of the saw-scaled or carpet viper (Echis ocellatus) in northern Nigeria, where bites by this species cause great morbidity and mortality but where effective antivenoms have become scarce and unaffordable. Selected antivenoms were destined to be compared by randomised controlled clinical trials (RCTs). Standard pre-clinical neutralisation assays were carried out in rodents. We included two licensed antivenoms of established clinical efficacy and 6 candidate antivenoms. Although 6 of the tested antivenoms showed promising efficacy, all but 3 were excluded from further study because of inadequate pre-clinical efficacy or because they were unavailable or unaffordable for the anticipated RCTs. Median effective doses (ED(50)) of the remaining three candidate antivenoms suggested that the following doses might neutralise the maximum observed venom yield of 24.8 mg (dry weight) of venom milked from captive E. ocellatus: 10 ml of MicroPharm "EchiTAb G" (ET-G) antivenom; 30 ml of Instituto Clodomiro Picado "EchiTAb-Plus-ICP" (ET-Plus) antivenom; 50 ml of VacSera, Cairo "EgyVac" antivenom. A preliminary clinical dose-finding and safety study of these three antivenoms was carried out in 24 patients with incoagulable blood after E. ocellatus bites who were not severely envenomed. A 3+3 dose escalation design was employed. Initial doses of 10 ml ET-G and 30 ml ET-Plus restored blood coagulability in groups of 6 patients with early mild reactions (pruritus only) in not more than one third of them. EgyVac antivenom did not fulfil efficacy or safety criteria in 12 patients. On the basis of these results, ET-G and ET-Plus were selected for comparison in a RCT.

  15. Chronic lymphocytic leukemia in African Americans.

    PubMed

    Coombs, Catherine C; Falchi, Lorenzo; Weinberg, J Brice; Ferrajoli, Alessandra; Lanasa, Mark C

    2012-11-01

    Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia in the United States with almost 4390 attributable deaths per year. Epidemiologic data compiled by the Surveillance, Epidemiology and End Results (SEER) program identifies important differences in incidence and survival for African Americans with CLL. Although the incidence of CLL is lower among African Americans than among Caucasians (4.6 and 6.2 per 100 000 men, respectively), age-adjusted survival is inferior. African American patients with CLL are almost twice as likely to die from a CLL-related complication in the first 5 years after diagnosis as are Caucasian patients with CLL. The biologic basis for these observations is almost entirely unexplored, and a comprehensive clinical analysis of African American patients with CLL is lacking. This is the subject of the present review.

  16. HIV/AIDS among African Americans

    MedlinePlus

    ... person’s chance of getting or transmitting HIV. The poverty rate is higher among African Americans than other racial/ethnic groups. The socioeconomic issues associated with poverty—including limited access to high-quality health care, ...

  17. Cardiac assessment of African hedgehogs (Atelerix albiventris).

    PubMed

    Black, Peter A; Marshall, Cecilia; Seyfried, Alice W; Bartin, Anne M

    2011-03-01

    Cardiomyopathy is a common finding in captive African hedgehogs (Atelerix albiventris) at postmortem exam. To date, treatment attempts have been mostly empirical and unrewarding. The objective of this study was to determine reference cardiac values for captive African hedgehogs based on echocardiogram, electrocardiogram (ECG), and radiographs. Adult African hedgehogs with no clinical signs of cardiac disease (n = 13) were selected. Each animal was anesthetized with isoflurane via facemask and an echocardiogram, ECG, and radiographs were performed. Standard measurements were taken and the descriptive statistics performed. Values were comparable to limited data available in other hedgehog species and other similar-sized exotic species. Two animals were removed from consideration of reference values due to valvular defects that were considered significant. These data are the first establishing cardiac parameters in normal African hedgehogs using radiographic cardiac measurement, echocardiogram, and ECG. Evaluating animals with possible cardiomyopathy may allow for earlier diagnosis and more successful treatment.

  18. Mellonee Burnim on African American Music.

    ERIC Educational Resources Information Center

    Campbell, Patricia Shehan

    1995-01-01

    Describes the role and influence of Mellonee Burnim on U.S. music education. Discusses the origins and impact of African American gospel music. Includes a list of selected resources and two lesson plans featuring gospel music. (CFR)

  19. What physicians should know about Africanized honeybees.

    PubMed Central

    Sherman, R A

    1995-01-01

    The Africanized honeybee, popularly known as the "killer bee," is already well established in Texas and has recently entered California and Arizona. As the Africanized honeybee spreads in North America, the medical community must become aware of the problems associated with this insect and ensure that sting emergencies can be handled quickly and appropriately. The major differences between Africanized and European honeybees are that the former are more irritable, they swarm more readily and frequently, they defend their hives more vehemently, and they sting more collectively. It is not the composition nor the volume of an individual bee's venom, but rather the cumulative dose of multiple stings that accounts for the morbidity and mortality associated with Africanized honeybee-sting incidents. Even nonallergic persons are susceptible to the toxic effects of these large combined venom loads. Africanized honeybee-sting victims are treated the same as victims of European honeybee stings. Authorities will prepare for the bees' arrival by expanding public awareness, teaching risk-avoidance behavior, providing for the removal of troublesome hives, and developing sting treatment protocols that can be initiated rapidly in the field or emergency departments. Health care professionals should participate in the educational efforts and in the development of needed emergency response protocols so that the effects of the Africanized honeybee will be merely a nuisance rather than a plague. PMID:8553637

  20. Partiality and distributive justice in African bioethics.

    PubMed

    Wareham, Christopher Simon

    2017-04-01

    African ethical theories tend to hold that moral agents ought to be partial, in the sense that they should favour members of their family or close community. This is considered an advantage over the impartiality of many Western moral theories, which are regarded as having counterintuitive implications, such as the idea that it is unethical to save a family member before a stranger. The partiality of African ethics is thought to be particularly valuable in the context of bioethics. Thaddeus Metz, in particular, argues that his African-derived theory best accounts for a number of plausible intuitions, such as the intuition that health care practitioners ought to be biased towards the patients for whom they are directly responsible. In this article, I claim that the plausible intuitions drawn on in favour of partiality can be satisfactorily explained on the basis of impartial moral theories. Moreover, I argue that blanket acceptance of partiality has problematic consequences for distributive justice in resource allocation in biomedical contexts. By contrast, impartial theories can justify plausible instances of partiality whilst avoiding the pitfalls of fully partial moral theories. Although this provides grounds for abandoning partiality in principle, I claim that this finding should not be seen as damaging to African medical ethics. Instead, it prompts investigation of underexplored possibilities of impartial African moral theories. To demonstrate the value of this direction, I sketch some novel and attractive conceptions that combine impartiality with elements of African ethics.

  1. Port of Sanctuary: The Aesthetic of the African/African American and the Barnes Foundation.

    ERIC Educational Resources Information Center

    Hollingsworth, Charles H.

    1994-01-01

    Asserts that, although it has been ignored by most art historians and art educators, the Barnes Foundation was founded upon a unique African/African American esthetic influence. Describes influences on the life of Dr. Albert C. Barnes, his world view, and the decision to establish the Barnes Foundation and its art collection. (CFR)

  2. Trade in Educational Services: Reflections on the African and South African Higher Education System

    ERIC Educational Resources Information Center

    Sehoole, Chika Trevor

    2004-01-01

    This article discusses and analyses the emergence of globalisation and its impact on developments within the African continent. Africa's response at a regional level through the New Partnership for Africa's Development and at a subregional level through the Southern African Development Community's "Protocol on Education" come under…

  3. "Women ... Mourn and Men Carry on": African Women Storying Mourning Practices--A South African Example

    ERIC Educational Resources Information Center

    Kotze, Elmarie; Els, Lishje; Rajuili-Masilo, Ntsiki

    2012-01-01

    African mourning of loss of lives in South Africa has been shaped by discursive practices of both traditional African cultures and the sociopolitical developments under apartheid and in post-apartheid South Africa. This article reports on changes in mourning practices on the basis of a literature review and uses a collection of examples to…

  4. African American Pastors' Beliefs and Actions Regarding Childhood Incest in the African American Community

    ERIC Educational Resources Information Center

    Wells, Tesia Denis

    2012-01-01

    This quantitative study sought to explore African American pastors' beliefs and actions regarding childhood incest in the African American community and their decisions to inform the proper authorities. This exploratory study was developed in order to draw both public and academic attention to the understudied phenomenon of childhood incest within…

  5. An Ambivalent Community: International African Students in Residence at a South African University

    ERIC Educational Resources Information Center

    Weber, Everard

    2016-01-01

    This is a qualitative case study of the experiences and perceptions of South African and especially international, African students living in university residences in South Africa. The concept, community, is used to interpret interview data. This community was characterised by ambivalent social relations: There was discrimination by South Africans…

  6. The Pedagogy of African American Parents: Learning from Educational Excellence in the African American Community

    ERIC Educational Resources Information Center

    Watkins, Audrey P.

    2006-01-01

    This qualitative study of how parents teach their children to excel academically in the African American community seeks to establish the validity of the pedagogical practices of working class African American families by investigating the educational leadership of two families on Chicago's south side. The study acknowledges the significance of…

  7. African swine fever virus serotype-specific proteins are significant protective antigens for African swine fever

    Technology Transfer Automated Retrieval System (TEKTRAN)

    African swine fever (ASF) is an emerging disease threat for the swine industry worldwide. No ASF vaccine is available and progress is hindered by lack of knowledge concerning the extent of African swine fever virus (ASFV) strain diversity and the viral antigens conferring type specific protective im...

  8. Changing Fatherhood: An Exploratory Qualitative Study with African and African Caribbean Men in England

    ERIC Educational Resources Information Center

    Williams, Robert; Hewison, Alistair; Wildman, Stuart; Roskell, Carolyn

    2013-01-01

    This paper presents findings from a qualitative study undertaken with 46 African and African Caribbean men exploring their experiences of fatherhood. Data analysis was informed by Connell's theoretical work on changing gender relations. Findings indicate that fathers' lives were mediated by masculinities, racism, gender, migration and generational…

  9. A SNP test to identify Africanized honeybees via proportion of 'African' ancestry.

    PubMed

    Chapman, Nadine C; Harpur, Brock A; Lim, Julianne; Rinderer, Thomas E; Allsopp, Michael H; Zayed, Amro; Oldroyd, Benjamin P

    2015-11-01

    The honeybee, Apis mellifera, is the world's most important pollinator and is ubiquitous in most agricultural ecosystems. Four major evolutionary lineages and at least 24 subspecies are recognized. Commercial populations are mainly derived from subspecies originating in Europe (75-95%). The Africanized honeybee is a New World hybrid of A. m. scutellata from Africa and European subspecies, with the African component making up 50-90% of the genome. Africanized honeybees are considered undesirable for bee-keeping in most countries, due to their extreme defensiveness and poor honey production. The international trade in honeybees is restricted, due in part to bans on the importation of queens (and semen) from countries where Africanized honeybees are extant. Some desirable strains from the United States of America that have been bred for traits such as resistance to the mite Varroa destructor are unfortunately excluded from export to countries such as Australia due to the presence of Africanized honeybees in the USA. This study shows that a panel of 95 single nucleotide polymorphisms, chosen to differentiate between the African, Eastern European and Western European lineages, can detect Africanized honeybees with a high degree of confidence via ancestry assignment. Our panel therefore offers a valuable tool to mitigate the risks of spreading Africanized honeybees across the globe and may enable the resumption of queen and bee semen imports from the Americas.

  10. African Games of Strategy: A Teaching Manual. African Outreach Series, No. 2.

    ERIC Educational Resources Information Center

    Crane, Louise

    Appreciation of African games has increased in this country; especially board games which have been popularized through commercial versions. African games are invaluable resources for studying subjects requiring mathematical concepts, as well as social studies, history, geography, and languages. This manual presents some of the better known…

  11. Antigenic variation in African trypanosomes

    PubMed Central

    Horn, David

    2014-01-01

    Studies on Variant Surface Glycoproteins (VSGs) and antigenic variation in the African trypanosome, Trypanosoma brucei, have yielded a remarkable range of novel and important insights. The features first identified in T. brucei extend from unique to conserved-among-trypanosomatids to conserved-among-eukaryotes. Consequently, much of what we now know about trypanosomatid biology and much of the technology available has its origin in studies related to VSGs. T. brucei is now probably the most advanced early branched eukaryote in terms of experimental tractability and can be approached as a pathogen, as a model for studies on fundamental processes, as a model for studies on eukaryotic evolution or often all of the above. In terms of antigenic variation itself, substantial progress has been made in understanding the expression and switching of the VSG coat, while outstanding questions continue to stimulate innovative new approaches. There are large numbers of VSG genes in the genome but only one is expressed at a time, always immediately adjacent to a telomere. DNA repair processes allow a new VSG to be copied into the single transcribed locus. A coordinated transcriptional switch can also allow a new VSG gene to be activated without any detectable change in the DNA sequence, thereby maintaining singular expression, also known as allelic exclusion. I review the story behind VSGs; the genes, their expression and switching, their central role in T. brucei virulence, the discoveries that emerged along the way and the persistent questions relating to allelic exclusion in particular. PMID:24859277

  12. African female sexuality and the heterosexual form.

    PubMed

    Mcfadden, P

    1994-03-01

    All women find sexuality problematical, especially women living in countries that were colonized or colonized others. The stereotype of repressed sexuality in Victorian England found its antithesis in the stereotype of promiscuous African sexuality which had to be "civilized" and controlled through religion and repression. Colonizing nations have seen the discourse on sexuality move from the private to the public domain, while Africa maintains its silence on the subject. Sexuality is a difficult topic because it embraces the most intimate and individual of our human emotions, thus, it is difficult even to voice sexual preferences to a lifetime partner. In addition, especially in Africa, sexuality is a very gender-specific social construct. Africans foster heterosexuality through socialization from early childhood and discourage any sign of sexual stimulation in their children. After teaching that humans are "naturally" heterosexual, Africans teach their children that marriage is essential for the moral uprightness of society, although most Africans are, in fact, raised in many types of alternative families. Critique of the heterosexual form is literally nonexistent in African feminist genre because African sexuality is really male sexuality. When people assert that an African culture exists, they really mean that patriarchal constructs about maleness and femaleness pervade the continent. Women are not expected to experience sexual satisfaction, and, indeed, the practice of female genital mutilation assures that they will never experience sexual pleasure. This practice assures that female sexuality exists only through men. It represents a misogynist point of view about the female body and is equally repulsive whether it takes the form of "excision" of a part of the clitoris or removal of all of the external genitalia. This practice controls female sexuality by depriving women of the opportunity to masturbate or to engage in homosexual relations. The resulting option

  13. Afriphone Literature as a Prototypical Form of African Literature: Insights from Prototype Theory

    ERIC Educational Resources Information Center

    Bodomo, Adams

    2016-01-01

    What is the most prototypical form of African literature? Shouldn't we be using African languages to produce African literary texts, shouldn't we produce more Afriphone African literature compared to Europhone African literature or Afro-Europhone literature? This issue underlies the reality that the vast majority of African writers presumably…

  14. Pattern of breast cancer among white-American, African-American, and nonimmigrant west-African women.

    PubMed Central

    Ijaduola, T. G.; Smith, E. B.

    1998-01-01

    This study reviews the current understanding of the pattern of breast cancer among whites, African Americans, and West Africans who have never immigrated to the US to find better ways of improving the prevention, early detection, and care of breast cancer world-wide. In the United States, the behavior pattern of breast cancer in African-American women differs from that of white women. Among the three populations, breast cancer appears to be least common in nonimmigrant West-African women. The peak incidence in African Americans and West Africans occurs around the premenopausal period while it occurs postmenopausal period in whites. Also, unlike white women, West-African and African-American women present late for treatment with a greater cancer burden and consequently lower survival rates. The predominant histological type is infiltrating ductal carcinoma in the three groups but the highest percentage (33%) of infiltrating poorly differentiated anaplastic carcinoma occurs in West Africans. Menstrual and obstetric history, obesity, and high body mass index status appear to be greater specific risk factors among African Americans than among West Africans. African Americans and West Africans have three "Ls" in common: late stage in seeking treatment, lower age at peak incidence with severe tumor burden, and consequently lower survival rates. There is a need for more detailed population-based research at molecular levels to elucidate the basis for some of these features. PMID:9770955

  15. The African University and the Duty to Co-Operate.

    ERIC Educational Resources Information Center

    Agblemagnon, N'Sougan

    1984-01-01

    Because of their history rooted in human rights, African universities can now practically and politically undertake international and interinstitutional cooperative projects for human rights and intercultural understanding, especially through such alliances as the Association of African Universities. (MSE)

  16. Men of African Descent and Carcinoma of the Prostate Consortium

    Cancer.gov

    The Men of African Descent and Carcinoma of the Prostate Consortium collaborates on epidemiologic studies to address the high burden of prostate cancer and to understand the causes of etiology and outcomes among men of African ancestry.

  17. What about African Americans and High Blood Pressure?

    MedlinePlus

    ANSWERS by heart Lifestyle + Risk Reduction High Blood Pressure What About African Americans and High Blood Pressure? The prevalence of high blood pressure in African Americans is among the highest in ...

  18. Chemotherapy of human African trypanosomiasis.

    PubMed

    Burchmore, Richard J S; Ogbunude, Patrick O J; Enanga, Bertin; Barrett, Michael P

    2002-01-01

    Human African trypanosomiasis or sleeping sickness is resurgent [1,2]. The disease is caused by subspecies of the parasitic haemoflagellate, Trypanosoma brucei. Infection starts with the bite of an infected tsetse fly (Glossina spp.). Parasites move from the site of infection to the draining lymphatic vessels and blood stream. The parasites proliferate within the bloodstream and later invade other tissues including the central nervous system. Once they have established themselves within the CNS, a progressive breakdown of neurological function accompanies the disease. Coma precedes death during this late phase. Two forms of the disease are recognised, one caused by Trypanosoma brucei rhodesiense, endemic in Eastern and Southern Africa, in which parasites rapidly invade the CNS causing death within weeks if untreated. T. b. gambiense, originally described in West Africa, but also widespread in Central Africa, proliferates more slowly and can take several years before establishing a CNS-involved infection. Many countries are in the midst of epidemics caused by gambiense-type parasites. Four drugs have been licensed to treat the disease [3]; two of them, pentamidine and suramin, are used prior to CNS involvement. The arsenic-based drug, melarsoprol is used once parasites are established in the CNS. The fourth, eflornithine, is effective against late stage disease caused by T. b. gambiense, but is ineffective against T. b. rhodesiense. Another drug, nifurtimox is licensed for South American trypanosomiasis but also been used in trials against melarsoprol-refractory late sage disease. This review focuses on what is known about modes of action of current drugs and discusses targets for future drug development.

  19. Vitrectomy with or without encircling band for pseudophakic retinal detachment: a multi-centre, three-arm, randomised clinical trial. VIPER Study Report No. 1—design and enrolment

    PubMed Central

    Mazinani, B; Baumgarten, S; Schiller, P; Agostini, H; Helbig, H; Limburg, E; Hellmich, M; Walter, P

    2016-01-01

    Purpose Scleral buckling is currently used in addition to vitrectomy for the treatment of pseudophakic retinal detachment (PRD) to better support the vitreous base and better visualisation of the periphery. Aims The aims of this study are to evaluate (1) whether the combination of 20 G vitrectomy and scleral buckling is superior to 20 G vitrectomy alone (control) (confirmatory), and (2) whether transconjunctival 23/25 G vitrectomy is non-inferior to 20 G vitrectomy (both without scleral buckling) regarding operation success (exploratory). Methods The VIPER (Vitrectomy Plus Encircling Band Vs. Vitrectomy Alone For The Treatment Of Pseudophakic Retinal Detachment) study is an unmasked, multi-centre, three-arm randomised trial. Patients with PRD were eligible, excluding complicated retinal detachment or otherwise severe ophthalmologic impairment. Patients were randomised to one of three interventions: 20 G vitrectomy alone (control C), combination of 20 G vitrectomy and circumferential scleral buckling (experimental treatment E1) or 23/25 G vitrectomy alone (experimental treatment E2). The primary endpoint is the absence of any indication for a retina re-attaching procedure during 6 months of follow-up. Secondary endpoints include best corrected visual acuity, retina re-attaching procedures, complications and adverse events. Results From June 2011 to August 2013, 257 patients were enrolled in the study. The internet randomisation service assigned 100 patients each to the treatment arms C and E1, and 57 patients to treatment E2. The imbalance is due to the fact that several retinal surgeons did not qualify for performing E2. The random assignment was stratified and balanced (ie, 1:1 or 1:1:1 ratio) by surgeon. Conclusions The described study represents a methodologically rigorous protocol evaluating the benefits of three different vitrectomy approaches to PRD. The projected results will help to establish their overall efficacy and will permit

  20. KSC kicks off African-American History Month

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Clothed in her traditional African garb, Michelle Amos, mistress of ceremonies, welcomes the audience on Feb. 3 at the kick-off of African-American History Month. The theme for this year's observation is 'Heritage and Horizons: The African-American Legacy and the Challenges of the 21st Century.' February is designated each year as a time to celebrate the achievements and contributions of African Americans to Kennedy Space Center, NASA and the nation.

  1. Lift every voice: voices of African-American lesbian elders.

    PubMed

    Woody, Imani

    2015-01-01

    Old lesbians of African descent have experienced racism, heterosexism, homophobia, and ageism. This article explores the topics of aging, ageism, heterosexism, and minority stress among older African-American lesbians. The narratives and subsequent analysis offer significant contributions to the dialogue regarding Black aging lesbians in the aging and lesbian, gay, bisexual, and transgender (LGBT) communities generally and in the African-American and African-American lesbian communities specifically.

  2. Population Genomics of sub-saharan Drosophila melanogaster: African diversity and non-African admixture.

    PubMed

    Pool, John E; Corbett-Detig, Russell B; Sugino, Ryuichi P; Stevens, Kristian A; Cardeno, Charis M; Crepeau, Marc W; Duchen, Pablo; Emerson, J J; Saelao, Perot; Begun, David J; Langley, Charles H

    2012-01-01

    Drosophila melanogaster has played a pivotal role in the development of modern population genetics. However, many basic questions regarding the demographic and adaptive history of this species remain unresolved. We report the genome sequencing of 139 wild-derived strains of D. melanogaster, representing 22 population samples from the sub-Saharan ancestral range of this species, along with one European population. Most genomes were sequenced above 25X depth from haploid embryos. Results indicated a pervasive influence of non-African admixture in many African populations, motivating the development and application of a novel admixture detection method. Admixture proportions varied among populations, with greater admixture in urban locations. Admixture levels also varied across the genome, with localized peaks and valleys suggestive of a non-neutral introgression process. Genomes from the same location differed starkly in ancestry, suggesting that isolation mechanisms may exist within African populations. After removing putatively admixed genomic segments, the greatest genetic diversity was observed in southern Africa (e.g. Zambia), while diversity in other populations was largely consistent with a geographic expansion from this potentially ancestral region. The European population showed different levels of diversity reduction on each chromosome arm, and some African populations displayed chromosome arm-specific diversity reductions. Inversions in the European sample were associated with strong elevations in diversity across chromosome arms. Genomic scans were conducted to identify loci that may represent targets of positive selection within an African population, between African populations, and between European and African populations. A disproportionate number of candidate selective sweep regions were located near genes with varied roles in gene regulation. Outliers for Europe-Africa F(ST) were found to be enriched in genomic regions of locally elevated

  3. Antineoplastic constituents of some Southern African plants.

    PubMed

    Charlson, A J

    1980-12-01

    Extracts of several Southern African plants which have been used in folk remedies have been prepared, and the extracts were tested in a variety of experimental tumour test-systems. Raphionacme hirsuta and Cheilanthes contracta have been used in African anticancer medicines. Extracts of these plants showed antitumor activity in some rodent test-systems, but the results were not confirmed. In the folk-lore, Haemanthus natalensis has been used in emetics and Urginea capitata preparations have been used to vaccinate African chiefs. Extracts of these plants showed significant cytotoxicity in the KB cell culture test-system. Infusions of Brunsvigia radulosa have been used as folk remedies for abdominal troubles. An extract of this Amaryllis plant increased the life span of P-388 leukaemic mice. Amaryllis bellandonna has also been investigated. Extracts of Amaryllis belladonna had to be fractionated in order to produce significant antitumour activity in the P-388 lymphocytic leukaemia test-system.

  4. IDEAL Symposium on the East African Lakes

    NASA Astrophysics Data System (ADS)

    Johnson, T. C.; Kelts, K.; Lehman, J. T.; Wuest, A.

    A vast array of interdisciplinary problems presented by the African Great Lakes were highlighted at the International Symposium on the Limnology, Climatology and Paleoclimatology of the East African Lakes, organized by the International Decade for the East African Lakes (IDEAL) February 17-21 in Jinja, Uganda. Approximately 125 scientists attended from North America, Europe, Africa, and New Zealand. Jinja is located on the northern shore of Lake Victoria at the head-waters of the Nile and is the site of the host institution for the symposium, the Uganda Freshwater Fisheries Research Organization (UFFRO). The conveners of the symposium were Tom Johnson of Duke University, George Kitaka of UNESCO-ROSTA, and Eric Odada of the University of Nairobi.

  5. Trichomonas vaginalis, HIV, and African-Americans.

    PubMed Central

    Sorvillo, F.; Smith, L.; Kerndt, P.; Ash, L.

    2001-01-01

    Trichomonas vaginalis may be emerging as one of the most important cofactors in amplifying HIV transmission, particularly in African-American communities of the United States. In a person co-infected with HIV, the pathology induced by T. vaginalis infection can increase HIV shedding. Trichomonas infection may also act to expand the portal of entry for HIV in an HIV-negative person. Studies from Africa have suggested that T. vaginalis infection may increase the rate of HIV transmission by approximately twofold. Available data indicate that T. vaginalis is highly prevalent among African-Americans in major urban centers of the United States and is often the most common sexually transmitted infection in black women. Even if T. vaginalis increases the risk of HIV transmission by a small amount, this could translate into an important amplifying effect since Trichomonas is so common. Substantial HIV transmission may be attributable to T. vaginalis in African-American communities of the United States. PMID:11747718

  6. Cancer statistics for African Americans, 2013.

    PubMed

    DeSantis, Carol; Naishadham, Deepa; Jemal, Ahmedin

    2013-05-01

    In this article, the American Cancer Society estimates the number of new cancer cases and deaths for African Americans and compiles the most recent data on cancer incidence, mortality, survival, and screening prevalence based upon incidence data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries and mortality data from the National Center for Health Statistics. It is estimated that 176,620 new cases of cancer and 64,880 deaths will occur among African Americans in 2013. From 2000 to 2009, the overall cancer death rate among males declined faster among African Americans than whites (2.4% vs 1.7% per year), but among females, the rate of decline was similar (1.5% vs 1.4% per year, respectively). The decrease in cancer death rates among African American males was the largest of any racial or ethnic group. The reduction in overall cancer death rates since 1990 in men and 1991 in women translates to the avoidance of nearly 200,000 deaths from cancer among African Americans. Five-year relative survival is lower for African Americans than whites for most cancers at each stage of diagnosis. The extent to which these disparities reflect unequal access to health care versus other factors remains an active area of research. Overall, progress in reducing cancer death rates has been made, although more can and should be done to accelerate this progress through ensuring equitable access to cancer prevention, early detection, and state-of-the-art treatments.

  7. The management of hypertension in African Americans.

    PubMed

    Ferdinand, Keith C; Armani, Annemarie M

    2007-06-01

    The prevalence of hypertension in blacks in the United States is among the highest in the world. Compared with whites, blacks develop hypertension at an earlier age, their average blood pressures are much higher and they experience worse disease severity. Consequently, blacks have a 1.3 times greater rate of nonfatal stroke, 1.8 times greater rate of fatal stroke, 1.5 times greater rate of heart disease death, 4.2 times greater rate of end-stage kidney disease, and a 50% higher frequency of heart failure; overall, mortality due to hypertension and its consequences is 4 to 5 times more likely in African Americans than in whites. The increased prevalence of hypertension and excessive target organ damage is due to a combination of genetic and, most likely, environmental factors. There are no clinical trial data at present to suggest that lower-than-usual BP targets should be set for high-risk demographic groups such as African Americans. The primary means of prevention and early treatment of hypertension in African Americans will be the appropriate use of lifestyle modification. The International Society of Hypertension in Blacks guidelines realize that most patients will require combination therapy, many of them first-line, to reach appropriate BP goals. Although certain classes and combinations of antihypertensive agents have been well-established to be effective, the choice of drugs for combination therapy in African American patients may be different. Within the African American group, the responsiveness to monotherapy with ACE inhibitors, angiotensin receptor blockers, and beta blockers may be less than the responsiveness to diuretics and calcium channel blockers, but these differences are corrected when diuretics are added to the neurohormonal antagonists. Of note, African American patients with systolic BP >15 mm Hg or a diastolic BP >10 mm Hg above goal should be treated with first-line combination therapy.

  8. Assessing the contributions of East African and West Pacific warming to the 2014 boreal spring East African drought

    USGS Publications Warehouse

    Funk, Christopher C.; Shukla, Shraddhanand; Hoell, Andrew; Livneh, Ben

    2015-01-01

    Anthropogenic warming contributed to the 2014 East African drought by increasing East African and west Pacific temperatures, and increasing the gradient between standardized western and central Pacific SST causing reduced rainfall, evapotranspiration, and soil moisture.

  9. Oral Cancer in African Americans: Addressing Health Disparities

    ERIC Educational Resources Information Center

    Dodd, Virginia J.; Watson, Jennifer M.; Choi, Youjin; Tomar, Scott L.; Logan, Henrietta L.

    2008-01-01

    Objectives: To explore factors underlying African Americans' perceptions of oral cancer and the oral cancer exam. Study findings were used to guide development of oral cancer messages designed to increase oral cancer exams among African Americans. Methods: Focus groups were conducted to understand African Americans' attitudes and expectations…

  10. African American Acculturation and Black Racial Identity: A Preliminary Investigation.

    ERIC Educational Resources Information Center

    Pope-Davis, Donald B.; Liu, William M.; Ledesma-Jones, Shannon; Nevitt, Jonathan

    2000-01-01

    Examines the relationship between acculturation and racial identity among African Americans. One hundred eighty-seven African American students completed the Black Racial Identity Attitude Scale and the African American Acculturation Scale (AAAS). Acculturation was associated with three of the five AAAS subscales: Dissonance, Immersion, and…

  11. Exposure of African-American Youth to Alcohol Advertising.

    ERIC Educational Resources Information Center

    2003

    The marketing of alcohol products in African-American communities has, on occasion, stirred national controversy and met with fierce resistance from African Americans and others. Despite occasional media and community spotlights on the marketing of alcohol products in the African-American community, there has been no systematic review of the…

  12. Teaching African Politics at American Colleges and Universities: A Survey.

    ERIC Educational Resources Information Center

    Kenski, Henry C.; Kenski, Margaret C.

    Political scientists who teach African politics courses at U.S. colleges and universities were surveyed in 1973 to (1) discover successful teaching techniques, approaches, and texts; (2) determine the popularity of courses in African politics; and (3) collect data on the status of African politics as a research area. A questionnaire was mailed to…

  13. Neo-African Literature: A History of Black Writing.

    ERIC Educational Resources Information Center

    Jahn, Janheinz

    Chapters in this book classify the literature reflecting the overlap of African and Western cultures according to its content, stylistic features, and patterns of literary expression. Areas covered are (1) early writers of African descent; (2) the African scene--oral, Afro-Arabic, "apprentice" and "protest," and Southern Bantu literatures; (3) the…

  14. Exploring How African American Faculty Cope with Classroom Racial Stressors

    ERIC Educational Resources Information Center

    Pittman, Chavella T.

    2010-01-01

    This study was an examination of how African American faculty discussed their coping with racially stressful classrooms. Despite aims for racial equality in higher education, the classroom has been a significant site of racial stressors for African American facility. Analysis of interviews with 16 (8 women, 8 men) African American faculty at a…

  15. Engaging Youth through African-Derived Dance and Culture

    ERIC Educational Resources Information Center

    Franklin, Kikora

    2013-01-01

    This article provides a brief history of African and African-derived dance and culture and highlights the physical health, dance education, historical, and cultural benefits of a school-based program that incorporates African dance as its core component. The article also includes the phases of the programming and brings attention to potential…

  16. The Notion of Ubuntu and Communalism in African Educational Discourse

    ERIC Educational Resources Information Center

    Venter, Elza

    2004-01-01

    The notion of "ubuntu" and "communalism" is of great importance in an African educational discourse, as well as in African Philosophy of Education and in African philosophical discourse. "Ubuntu" is a philosophy that promotes the common good of society and includes humanness as an essential element of human growth. In…

  17. Achievement and Underachievement: The Experiences of African Caribbeans

    ERIC Educational Resources Information Center

    Rhamie, Jasmine

    2012-01-01

    The disproportionate representation of African Caribbeans in all the negative educational statistics has been well documented. Despite this, there are African Caribbeans who achieve academically but relatively few studies have explored this area. This study aimed to investigate the factors that contribute to African Caribbean academic success,…

  18. African-American Males' Health Perceptions and Knowledge

    ERIC Educational Resources Information Center

    McNeal, CoSandra; Perkins, Isaac; Lyons, Shenia

    2006-01-01

    Research on African American men's health is limited. Perception and knowledge of health may have a significant effect on health seeking behavior and self care. This study was designed to examine factors that may influence health perception and knowledge among African American males. This is a cross-sectional study of 343 African American males…

  19. Perceptions of Domestic Violence: A Dialogue with African American Women

    ERIC Educational Resources Information Center

    Bent-Goodley, Tricia B.

    2004-01-01

    Although empirical research has accumulated over the past 20 years regarding African Americans and domestic violence, many questions remain about African American perceptions of domestic violence. This article explores African American women's perceptions about domestic violence through three focus groups held at a New York social services agency.…

  20. African American Educational Leadership in the School Superintendency

    ERIC Educational Resources Information Center

    Smith, Eva C.

    2013-01-01

    African American educational leadership has long been part of American education and African American activism to resist oppression. However, the field of educational leadership has rarely included the contributions of African American leaders, particularly women leaders, into mainstream leadership theory and practices. This omission is difficult…

  1. Some Growth Points in African Child Development Research

    ERIC Educational Resources Information Center

    Serpell, Robert; Marfo, Kofi

    2014-01-01

    We reflect on ways in which research presented in earlier chapters responds to challenges of generating an African child development field and identify additional issues calling for the field's attention. The chapters collectively display a variety of African contexts and reflexive evidence of the authors' African cultural roots. Connecting…

  2. 77 FR 5375 - National African American History Month, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ... Documents#0;#0; ] Proclamation 8776 of January 31, 2012 National African American History Month, 2012 By the... for the better. During National African American History Month, we celebrate the rich legacy of... African American women are not limited to those recorded and retold in our history books. Their impact...

  3. 76 FR 6519 - National African American History Month, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-04

    ... February 4, 2011 Part II The President Proclamation 8627--National African American History Month, 2011 #0..., 2011 National African American History Month, 2011 By the President of the United States of America A... breaking down barriers. During National African American History Month, we celebrate the vast...

  4. From Crisis to Empowerment: African American Women in Community Colleges

    ERIC Educational Resources Information Center

    Bates, Marcie Ann

    2012-01-01

    Social challenges tear at the fabric of the African American family, revealing complexities that identify a de facto leader, the African American woman. She exists in a chasm of overt circumstances which heavily influences her successes. The purpose of this study is to identify factors that motivated seven female African American community college…

  5. The African Storybook and Language Teacher Identity in Digital Times

    ERIC Educational Resources Information Center

    Stranger--Johannessen, Espen; Norton, Bonny

    2017-01-01

    The African Storybook (ASb) is a digital initiative that promotes multilingual literacy for African children by providing openly licenced children's stories in multiple African languages, as well as English, French, and Portuguese. Based on Darvin and Norton's (2015) model of identity and investment, and drawing on the Douglas Fir Group's (2016)…

  6. Barriers to Hospice Use among African Americans: A Systematic Review

    ERIC Educational Resources Information Center

    Washington, Karla T.; Bickel-Swenson, Denise; Stephens, Nathan

    2008-01-01

    The present review was undertaken to explore recent evidence in the professional literature pertaining to use of hospice services by African Americans. The article addresses the research methods that have been used to study African American hospice use, obstacles to African American participation in hospice that have been identified, and…

  7. Persistence among African American Males in the Honors College

    ERIC Educational Resources Information Center

    Anderson Goins, Johnell Roxann

    2014-01-01

    Retaining African American students, specifically African American males, is an issue that plagues the American higher education system. Research shows that African American male students are the lowest represented group in the gifted studies programs (Ford, 2010). Lockie and Burke (1999); Chen and DeJardins (2010) and Bell (2010a) found that…

  8. African American Males in Counseling: Who's Pulling the Trigger Now?

    ERIC Educational Resources Information Center

    Bethea-Whitfield, Patricia

    African American males face numerous challenges to their physical and psychological well-being. This project is a survey of the literature and trends relative to African American males from 1987 to the present. In reviewing the fifteen years since Parham and McDavis published their now famous article on African American men as an endangered…

  9. Student-Centered Designs of Pan-African Literature Courses

    ERIC Educational Resources Information Center

    M'Baye, Babacar

    2010-01-01

    A student-centered teaching methodology is an essential ingredient of a successful Pan-African literary course. In this article, the author defines Pan-Africanism and how to go about designing a Pan-African literature course. The author combines reading assignments with journals, film presentations, and lectures in a productive learning…

  10. Representing African American Women in U.S. History Textbooks

    ERIC Educational Resources Information Center

    Schocker, Jessica B.; Woyshner, Christine

    2013-01-01

    This article addresses the dearth of African American women in high school U.S. history textbooks. The authors conducted a content analysis of the images in an African American history textbook and found that black women are underrepresented. Women are found in less than 15 percent of the images in the African American history text, while they…

  11. Empowerment Groups for Urban African American Girls: A Response

    ERIC Educational Resources Information Center

    Holcomb-McCoy, Cheryl C.

    2005-01-01

    Although the author wanted to read Bemak, Chung, and Siroskey-Sabdo's article in an objective sense, her response to their article is most likely influenced by her own experiences as an African American female and mother of an African American daughter. To her, the paramount issue facing African American females is the double and sometimes triple…

  12. Women of African Descent: Persistence in Completing Doctorates

    ERIC Educational Resources Information Center

    Iddrisu, Vannetta Bailey

    2010-01-01

    This study examines the educational persistence of women of African descent (WOAD) in pursuit of a doctorate degree at universities in the southeastern United States. WOAD are women of African ancestry born outside the African continent. These women are heirs to an inner dogged determination and spirit to survive despite all odds (Pulliam, 2003,…

  13. Against the Wind: Five South Africans Follow Their Dreams.

    ERIC Educational Resources Information Center

    Lewis, Lesley

    This book for beginning readers tells the story of five South Africans who, though not very famous, all did things that no black South African had ever done before. They include: Simon Mkhize who, year after year, ran the Comrades Marathon unofficially, ignoring its racial bans; Magema M. Fuze, who was the first black South African to publish a…

  14. An Exploration of African American Students' Attitudes toward Online Learning

    ERIC Educational Resources Information Center

    Okwumabua, Theresa M.; Walker, Kristin M.; Hu, Xiangen; Watson, Andrea

    2011-01-01

    The current work presents exploratory research findings concerning African American students' attitudes toward online learning. The Online Tutoring Attitudes Scale (OTAS; Graff, 2003) was administered to 124 African American students in a positive youth development program. Findings suggest that African American students' attitudes toward…

  15. Perceived Attractiveness, Facial Features, and African Self-Consciousness.

    ERIC Educational Resources Information Center

    Chambers, John W., Jr.; And Others

    1994-01-01

    Investigated relationships between perceived attractiveness, facial features, and African self-consciousness (ASC) among 149 African American college students. As predicted, high ASC subjects used more positive adjectives in descriptions of strong African facial features than did medium or low ASC subjects. Results are discussed in the context of…

  16. African Education Research. Part One: Issues and Patterns.

    ERIC Educational Resources Information Center

    Bigelow, Ross Edgar

    This study of 416 African Education Research (AER) projects was conducted to: (a) provide information on current studies by Africans on African education; (b) provide a framework for critical analysis of research based on a classification of the issues; and (c) provide a listing and discussion of continuing research resources which would aid…

  17. Diversity and origin of South African chickens.

    PubMed

    Mtileni, B J; Muchadeyi, F C; Maiwashe, A; Chimonyo, M; Groeneveld, E; Weigend, S; Dzama, K

    2011-10-01

    The objectives of this study were to analyze the genetic diversity and structure of South African conserved and field chicken populations and to investigate the maternal lineages of these chicken populations. Four South African conserved chicken populations (n = 89), namely, Venda (VD_C), Ovambo, Naked Neck, and Potchefstroom Koekoek from the Animal Production Institute of the Agricultural Research Council, and 2 field populations, the Venda and Ovambo (OV_F), from which the Ovambo and the Venda conservation flocks were assumed to have been sampled, were genotyped for 460 bp of the mitochondrial DNA (mtDNA) D-loop sequence. Haplotypes of these chickens were aligned to 7 Japanese and 9 Chinese and Eurasian chicken mtDNA D-loop sequences taken from GenBank and reflecting populations from presumed centers of domestication. Sequence analysis revealed 48 polymorphic sites that defined 13 haplotypes in the South African chicken populations. All 6 South African conserved and field chicken populations observed were found to be polymorphic, with the number of haplotypes ranging from 3 for VD_C to 8 for OV_F. The lowest haplotype diversity, 0.54 ± 0.08, was observed in VD_C chickens, whereas the highest value, 0.88 ± 0.05, was observed in OV_F chickens. Genetic diversity between the 4 South African conserved and 2 field chicken populations constituted 12.34% of the total genetic variation, whereas within-population diversity constituted 87.66% of the total variation. The median network analysis of the mtDNA D-loop haplotypes observed in the South African conserved and field populations and the reference set resulted in 5 main clades. All 6 South African chickens were equally represented in the major clade, E, which is presumed to be of Indian subcontinent maternal origin and may have its roots in Southeast Asia. The results showed multiple maternal lineages of South African chickens. Conservation flocks and field chicken populations shared the major haplotypes A, D and E

  18. Mammary gland tumors in captive African hedgehogs.

    PubMed

    Raymond, J T; Gerner, M

    2000-04-01

    From December 1995 to July 1999, eight mammary gland tumors were diagnosed in eight adult captive female African hedgehogs (Atelerix albiventris). The tumors presented as single or multiple subcutaneous masses along the cranial or caudal abdomen that varied in size for each hedgehog. Histologically, seven of eight (88%) mammary gland tumors were malignant. Tumors were classified as solid (4 cases), tubular (2 cases), and papillary (2 cases). Seven tumors had infiltrated into the surrounding stroma and three tumors had histologic evidence of neoplastic vascular invasion. Three hedgehogs had concurrent neoplasms. These are believed to be the first reported cases of mammary gland tumors in African hedgehogs.

  19. E-Voting: A South African Perspective

    NASA Astrophysics Data System (ADS)

    Swanepoel, E.; Thomson, K.; van Niekerk, J. F.

    The South African democracy, despite being worthy of admiration, is in its infancy. As such its electoral processes still needs to be nurtured and protected. Since 1994 there has been four national elections. All of these have been declared "free and fair" by the Independent Electoral Commission. However, there has been some problems and growing pains. This paper firstly discusses the current electoral system in South Africa. It then examines E-voting systems and discusses the feasibility of such a voting system for use in the South African context.

  20. The African VLBI network project

    NASA Astrophysics Data System (ADS)

    Loots, Anita

    2015-01-01

    larger teams in science, engineering and technology issues and collaborate with the broader global science community to develop new African radio astronomy science communities.

  1. Epidemiology of human African trypanosomiasis

    PubMed Central

    Franco, Jose R; Simarro, Pere P; Diarra, Abdoulaye; Jannin, Jean G

    2014-01-01

    Human African trypanosomiasis (HAT), or sleeping sickness, is caused by Trypanosoma brucei gambiense, which is a chronic form of the disease present in western and central Africa, and by Trypanosoma brucei rhodesiense, which is an acute disease located in eastern and southern Africa. The rhodesiense form is a zoonosis, with the occasional infection of humans, but in the gambiense form, the human being is regarded as the main reservoir that plays a key role in the transmission cycle of the disease. The gambiense form currently assumes that 98% of the cases are declared; the Democratic Republic of the Congo is the most affected country, with more than 75% of the gambiense cases declared. The epidemiology of the disease is mediated by the interaction of the parasite (trypanosome) with the vectors (tsetse flies), as well as with the human and animal hosts within a particular environment. Related to these interactions, the disease is confined in spatially limited areas called “foci”, which are located in Sub-Saharan Africa, mainly in remote rural areas. The risk of contracting HAT is, therefore, determined by the possibility of contact of a human being with an infected tsetse fly. Epidemics of HAT were described at the beginning of the 20th century; intensive activities have been set up to confront the disease, and it was under control in the 1960s, with fewer than 5,000 cases reported in the whole continent. The disease resurged at the end of the 1990s, but renewed efforts from endemic countries, cooperation agencies, and nongovernmental organizations led by the World Health Organization succeeded to raise awareness and resources, while reinforcing national programs, reversing the trend of the cases reported, and bringing the disease under control again. In this context, sustainable elimination of the gambiense HAT, defined as the interruption of the transmission of the disease, was considered as a feasible target for 2030. Since rhodesiense HAT is a zoonosis

  2. "Brothers Gonna Work It Out:" Understanding the Pedagogic Performance of African American Male Teachers Working with African American Male Students

    ERIC Educational Resources Information Center

    Brown, Anthony L.

    2009-01-01

    Drawing from ethnographic data, this paper explores how African American male teachers working with African American male students performed their pedagogy. This paper highlights how teachers' understanding of African American males social and educational needs shaped their pedagogical performance. Interestingly however, teachers' performance was…

  3. "Now the African reigns supreme": the rise of African boxing on the Witwatersrand, 1924-1959.

    PubMed

    Fleming, Tyler

    2011-01-01

    This essay explores the growth of boxing among the African populations on the Witwatersrand region of South Africa between 1924 and 1959. It details how the sport's jump in popularity with Africans paralleled migration to Johannesburg. Africans increasingly saw boxing as an activity and skill conducive with survival in this new environment, and thus the sport grew in popularity, stature, and skill-level amongst this emergent urban population. The essay further explores the various ways that the sport was disseminated and popularized during the era, thus detailing how the sport reached both the African masses and petit-bourgeois educated elite. As their presence in Johannesburg became more and more permanent, boxing came to encompass various meanings and ideals, such as notions of discipline, independence and civility, to these urban populations.

  4. The African Renaissance and its relation to the geosciences: a South African perspective

    NASA Astrophysics Data System (ADS)

    Mtimkulu, M. N.; Motloung, M.; Graham, I. T.; Eriksson, P. G.; Bumby, A. J.

    2001-08-01

    Implicit in the African Renaissance is the synergy between government, the private sector, the educated minority and the disadvantaged majority. For this concept to work, belief and commitment must arise first from the African individual, whatever his or her potential contribution may be. The geosciences in South Africa provide a currently vibrant example of such cooperation, which has the potential to contribute significantly to the upliftment of the country and its neighbouring states. Based largely on personal interviews with various role players, from the Presidency of South Africa, through ministerial levels, the corporate sector and down to the individual, we present a spectrum of viewpoints and initiatives which are starting to result in practical implementation of the African revival. An end to conflict and xenophobia, the entrenchment of democratic government and corporate expression of the entrepreneurial spirit are essential to provide the framework within which the individual African can become a "Renaissance Man or Woman".

  5. African-American mitochondrial DNAs often match mtDNAs found in multiple African ethnic groups

    PubMed Central

    Ely, Bert; Wilson, Jamie Lee; Jackson, Fatimah; Jackson, Bruce A

    2006-01-01

    Background Mitochondrial DNA (mtDNA) haplotypes have become popular tools for tracing maternal ancestry, and several companies offer this service to the general public. Numerous studies have demonstrated that human mtDNA haplotypes can be used with confidence to identify the continent where the haplotype originated. Ideally, mtDNA haplotypes could also be used to identify a particular country or ethnic group from which the maternal ancestor emanated. However, the geographic distribution of mtDNA haplotypes is greatly influenced by the movement of both individuals and population groups. Consequently, common mtDNA haplotypes are shared among multiple ethnic groups. We have studied the distribution of mtDNA haplotypes among West African ethnic groups to determine how often mtDNA haplotypes can be used to reconnect Americans of African descent to a country or ethnic group of a maternal African ancestor. The nucleotide sequence of the mtDNA hypervariable segment I (HVS-I) usually provides sufficient information to assign a particular mtDNA to the proper haplogroup, and it contains most of the variation that is available to distinguish a particular mtDNA haplotype from closely related haplotypes. In this study, samples of general African-American and specific Gullah/Geechee HVS-I haplotypes were compared with two databases of HVS-I haplotypes from sub-Saharan Africa, and the incidence of perfect matches recorded for each sample. Results When two independent African-American samples were analyzed, more than half of the sampled HVS-I mtDNA haplotypes exactly matched common haplotypes that were shared among multiple African ethnic groups. Another 40% did not match any sequence in the database, and fewer than 10% were an exact match to a sequence from a single African ethnic group. Differences in the regional distribution of haplotypes were observed in the African database, and the African-American haplotypes were more likely to match haplotypes found in ethnic groups from

  6. African-American women and abortion: a neglected history.

    PubMed

    Ross, L J

    1992-01-01

    The history of African-American women's efforts to control their fertility is largely unknown. From slavery to the present, the growth rate of the African-American population has been cut in half. Demographers and historians frequently attribute this change to external factors such as poverty, disease, and coerced birth control, rather than the deliberate agency of African-American women. This essay assembles a brief historical record of the ways African-American women have sought to control their fertility through the use of abortion and birth control. It also examines the activism of African-American women in the establishment of family planning clinics and in defense of abortion rights.

  7. An Exploration of African Students in Malaysia

    ERIC Educational Resources Information Center

    Lian, Irene Tan Ai

    2011-01-01

    The exploratory study is an attempt to understand the reasons that prompted African students to study in Malaysia, the challenges encountered and the coping strategies used. The research on such topics among international students is well documented, but studies on international students in Malaysia are scarce. The sample included 155 African…

  8. Dissecting the genetic diversity in African rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    African cultivated rice, Oryza glaberrima, and its progenitor, O. barthii are excellent sources of important genes for rice improvement because they exhibit tolerance to several abiotic and biotic stresses. Development of advance backcross (ABC) populations between an unadapted donor parent and ada...

  9. Toward Understanding Korean and African American Relations.

    ERIC Educational Resources Information Center

    Chang, Edward Taehan

    1996-01-01

    Presents a lesson plan that examines the economic, cultural, and ideological factors that influence Korean and African American relations. Discusses how the two groups perceive each other and situates the role of race and class in this relationship. Includes informational handouts and discussion questions. (MJP)

  10. Art exhibit focuses on African astronomy

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-07-01

    Connections between Africans and astronomy are the focus of a new exhibition in the National Museum of African Art in Washington, D. C. "African Cosmos: Stellar Arts," which includes artwork, cultural items, and scientific displays from ancient to contemporary times, is the first major exhibit "that brings together arts and science focused on Africa's contribution to keen observations of the heavens over time," curator Christine Mullen Kreamer said at a 20 June news briefing. Among the exhibit's nearly 100 objects are an ancient Egyptian mummy board that includes a representation of the sky goddess Nut, sculptures by the Dogon people of Mali depicting figures in relation to the cosmos, a video that uses data from two square degrees of the Hubble Space Telescope Cosmic Evolution Survey, and a nearly floor-to-ceiling "Rainbow Serpent" constructed of plastic containers by Benin artist Hazoume. An untitled acrylic painting (Figure 1) by South African Gavin Jantjes evokes a myth of the Khoi San people of southern Africa, as it portrays a girl throwing evening fire embers into the night sky, where they remained as the Milky Way.

  11. In Pursuit of African Scholarship: Unpacking Engagement

    ERIC Educational Resources Information Center

    O'Brien, Frances

    2009-01-01

    Engagement between higher education and other societal sectors is a key theme in higher education discourse in South Africa, as it is in other countries. In South Africa, however, engagement has gained additional status as an appropriate strategy for pursuing African Scholarship. On the ground, however, inequitable power relationships and erratic…

  12. French-African Cultures: A Resource Unit.

    ERIC Educational Resources Information Center

    Forbes, Barbara

    This resource unit concerns French-African cultures and their influence on other cultures. The materials may be incorporated into Levels 3, 4, and 5 French classes. Topics in the outline include environmental aspects; historical background; and cultural differences expressed in Senegal, Guinee, Mali, Cote d'Ivoire, Haute Volta, Togo, Dahomey,…

  13. Liberty in African and Western Thought.

    ERIC Educational Resources Information Center

    Mudimbe, V. Y.

    The theoretical African mode of thinking about liberty seems to stand in contrast to the view of liberty that has dominated Western philosophy. Western philosophy accepts as its starting point the notion of an unconstrained and uncontextualized "I" that is defined in relation to the self and its inner being. Greek, Cartesian, and…

  14. Contemporary Sexism in the South African Navy

    ERIC Educational Resources Information Center

    Van Wijk, Charles H.

    2011-01-01

    The military traditionally embraces highly sexist attitudes. Over the past decade, the South African Navy (SAN) has been exposed to an increasingly progressive political environment. This study investigated contemporary expressions of sexism in the SAN. A representative sample of 476 sailors completed the Ambivalent Sexism Inventory, Modern Sexism…

  15. African and Pacific Literature: A Comparative Study.

    ERIC Educational Resources Information Center

    Martin, Kristine L.

    Literary writing in Africa and the Pacific addresses themes that reflect colonial experience and the struggles of newly independent nations to cope with change and conflicts between traditional and modern existence. The novels of Chinua Achebe of Nigeria and Ngugi Wa Thiong'o of Kenya illustrate many dominant themes of African literature. Achebe…

  16. City Children in African Children's Literature.

    ERIC Educational Resources Information Center

    Kuntz, Patricia S.

    A descriptive study identified titles and features of children's books set in an African city. Data were collected from various reviews of children's literature for titles published since 1980. In addition, the Cooperative Children's Book Center's log list of acquired titles for Africa from 1990 to 1996 was reviewed. Results showed that authors…

  17. One African Male in Higher Education

    ERIC Educational Resources Information Center

    Nichols, Robert L.

    2016-01-01

    Many predominantly White universities and colleges are seeking ways to both recruit and retain Black students (Simmons, J., Lowery-Hart, R., Wahl, S. T., & McBride, M. C. (2013). "Understanding the African-American student experience in higher education through a relational dialectics perspective." "Communication…

  18. Allocation of Students in North African Universities.

    ERIC Educational Resources Information Center

    Jones, Marie Thourson

    1981-01-01

    Student bodies at public universities in Morocco, Algeria, and Tunisia have grown rapidly, outside the direct control of university authorities. How the three North African nations differ in their policies regulating which students may study which subjects, and the implications of these policies for the goals of higher education are discussed.…

  19. African-American Axioms and Maxims.

    ERIC Educational Resources Information Center

    Zulu, Itibari M.

    1998-01-01

    Examines and describes 30 African-American centered quotation and motivational books, all but one of which were published between 1993 and 1997. The books articulate a diversity of genres and themes. Annotations are divided into: (1) general quotation; (2) daily words and meditation/motivation sources; (3) religion and theology; and (4)…

  20. Gravimetric maps of the Central African Republic

    NASA Technical Reports Server (NTRS)

    Albouy, J.; Godivier, R. (Principal Investigator)

    1982-01-01

    Gravimetric maps of the Central African Republic are described including a map of Bouguer anomalies at 1/1,000,000 in two sections (eastern sheet, western sheet) and a map, in color, of Bouguer anomalies at 1/2,000,000. Instrumentation, data acquisition, calibration, and data correction procedures are discussed.

  1. Reconceptualization of African American Self-Concept.

    ERIC Educational Resources Information Center

    Braithwaite, Harold, Jr.; And Others

    1994-01-01

    Focuses on how African American students define self-concept, and whether there is a specific black self-concept. Questionnaires completed by 60 undergraduates at a historically black college provide insight into student self-esteem and support the existence of a specific black self-concept. (SLD)

  2. African American's Perceptions of Psychotherapy and Psychotherapists.

    ERIC Educational Resources Information Center

    Thompson, Vetta L. Sanders; Akbar, Maysa D.; Bazile, Anita

    The attitudes and beliefs about utilization of mental health services of 201 African Americans, 18 years and older, are explored. One hundred and thirty-four females and 66 males participated in mixed sex focus groups conducted in an urban, Midwestern city. Discussion probes addressed participant perceptions of psychotherapists and psychotherapy,…

  3. Growing Up African American in Catholic Schools.

    ERIC Educational Resources Information Center

    Irvine, Jacqueline Jordan, Ed.; Foster, Michele, Ed.

    Contributors to this volume use their own stories to demonstrate success of one institution, the Catholic school system, in educating many African Americans who have gone on to make important contributions to the community. Their own experiences are the starting points for their reflections on the historical and sociological treatment of the…

  4. Colorectal Cancer in African Americans: An Update

    PubMed Central

    Williams, Renee; White, Pascale; Nieto, Jose; Vieira, Dorice; Francois, Fritz; Hamilton, Frank

    2016-01-01

    This review is an update to the American College of Gastroenterology (ACG) Committee on Minority Affairs and Cultural Diversity's paper on colorectal cancer (CRC) in African Americans published in 2005. Over the past 10 years, the incidence and mortality rates of CRC in the United States has steadily declined. However, reductions have been strikingly much slower among African Americans who continue to have the highest rate of mortality and lowest survival when compared with all other racial groups. The reasons for the health disparities are multifactorial and encompass physician and patient barriers. Patient factors that contribute to disparities include poor knowledge of benefits of CRC screening, limited access to health care, insurance status along with fear and anxiety. Physician factors include lack of knowledge of screening guidelines along with disparate recommendations for screening. Earlier screening has been recommended as an effective strategy to decrease observed disparities; currently the ACG and American Society of Gastrointestinal Endoscopists recommend CRC screening in African Americans to begin at age 45. Despite the decline in CRC deaths in all racial and ethnic groups, there still exists a significant burden of CRC in African Americans, thus other strategies including educational outreach for health care providers and patients and the utilization of patient navigation systems emphasizing the importance of screening are necessary. These strategies have been piloted in both local communities and Statewide resulting in notable significant decreases in observed disparities. PMID:27467183

  5. African Socialism and Educational Practice. Draft.

    ERIC Educational Resources Information Center

    Draisma, Tom

    The relationship between the secondary education system and wider political, economic, and sociocultural developments in Africa is examined. Special emphasis is given to the problems of political ideology and education in Zambia; but as Zambian socialist ideology and educational history show similarities to other African nations, the author's…

  6. Wages and Labor Management in African Manufacturing

    ERIC Educational Resources Information Center

    Fafchamps, Marcel; Soderbom, Mans

    2006-01-01

    Using matched employer-employee data from ten African countries, we examine the relationship between wages, worker supervision, and labor productivity in manufacturing. Wages increase with firm size for both production workers and supervisors. We develop a two-tier model of supervision that can account for this stylized fact and we fit the…

  7. African Universities Tackle the Continent's Agricultural Crisis

    ERIC Educational Resources Information Center

    Lindow, Megan

    2009-01-01

    Pests, population growth, and depleted soil have wreaked havoc on agriculture in Africa, so universities across the continent are rethinking how they teach the topic. Some African universities have been building their own networks and pooling their limited resources to train more agricultural scientists and improve their responsiveness to the…

  8. African rainforests: past, present and future

    PubMed Central

    Malhi, Yadvinder; Adu-Bredu, Stephen; Asare, Rebecca A.; Lewis, Simon L.; Mayaux, Philippe

    2013-01-01

    The rainforests are the great green heart of Africa, and present a unique combination of ecological, climatic and human interactions. In this synthesis paper, we review the past and present state processes of change in African rainforests, and explore the challenges and opportunities for maintaining a viable future for these biomes. We draw in particular on the insights and new analyses emerging from the Theme Issue on ‘African rainforests: past, present and future’ of Philosophical Transactions of the Royal Society B. A combination of features characterize the African rainforest biome, including a history of climate variation; forest expansion and retreat; a long history of human interaction with the biome; a relatively low plant species diversity but large tree biomass; a historically exceptionally high animal biomass that is now being severely hunted down; the dominance of selective logging; small-scale farming and bushmeat hunting as the major forms of direct human pressure; and, in Central Africa, the particular context of mineral- and oil-driven economies that have resulted in unusually low rates of deforestation and agricultural activity. We conclude by discussing how this combination of factors influences the prospects for African forests in the twenty-first century. PMID:23878339

  9. West African Folktales [and] Instructor's Manual.

    ERIC Educational Resources Information Center

    Gale, Steven H.

    Traditionally, an important function of folktales in West Africa has been to educate, as the older generation imparts knowledge to younger members of the family, tribe, societal unit, or ethnic group both informally in everyday life and more formally within the context of the bush schools. This anthology of West African folk literature offers more…

  10. African American College Women's Suicide Buffers.

    ERIC Educational Resources Information Center

    Marion, Michelle S.; Range, Lillian M.

    2003-01-01

    To examine the relationships buffers may have with suicide ideation, 300 African American female college students completed measures of suicide ideation and buffers. Three variables accounted for a significant and unique portion of the variance in suicide ideation: family support, a view that suicide is unacceptable, and a collaborative religious…

  11. The African Heritage in Spanish Caribbean Literature.

    ERIC Educational Resources Information Center

    Smart, Ian I.

    1981-01-01

    Uses Fanon's concept of the Manichean colonial situation and his Dialectical Theory of Identification to explore images of African heritage in the works of two mulatto Cuban poets, Gabriel de la Concepcion Valdez (1809-1844) and Nicolas Guillen (born 1902). (GC)

  12. Competency Development of Southern African Housing Officers

    ERIC Educational Resources Information Center

    Dunn, Munita; Dunkel, Norbert W.

    2013-01-01

    The Report on the Ministerial Committee for the Review of the Provision of Student Housing at South African Universities (Department of Higher Education and Training, 2011) has provided a comprehensive review of residences across several housing functional areas. In one of the residence management and administration recommendations it stated,…

  13. Intertextuality in EAP: An African Context

    ERIC Educational Resources Information Center

    Holmes, John

    2004-01-01

    This paper focuses on the development of EAP methodology within an African EAP context. I describe the setting up and implementation of an EAP study skills programme at the University of Asmara, Eritrea, over the period 1994-1998 and its subsequent development up to 2002. The unique social and political context of the EAP programme served as a…

  14. African Theatre and the University of Leeds

    ERIC Educational Resources Information Center

    Banham, Martin; Plastow, Jane

    2006-01-01

    This paper discusses the impact that teaching and research on African theatre in the Workshop Theatre of the University of Leeds' School of English may have had in Africa and elsewhere. After surveying the productivity and influence of the Workshop Theatre to the present, the authors ask if they have contributed meaningfully to the development,…

  15. African American Women Counselors, Wellness, and Spirituality

    ERIC Educational Resources Information Center

    Knowles, Debora; Bryant, Rhonda M.

    2011-01-01

    Given their tremendous professional responsibilities, professional counselors face daunting challenges to remaining healthy and avoiding role stress and overload. This article explores the intersection of race, gender, wellness, and spirituality in the self-care of African American women counselors. The authors give particular attention to…

  16. 2000 African American History Month Celebration Luncheon

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In the Early Space Exploration Conference Center at the KSC Visitor Complex, Dr. Julian M. Earls (left), deputy director for Operations, Glenn Research Center, receives a plaque from astronaut Joan Higginbotham (right) during the 2000 African American History Month Celebration Luncheon. Dr. Earls was guest speaker at the luncheon.

  17. 2000 African American History Month Celebration Luncheon

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In the Early Space Exploration Conference Center at the KSC Visitor Complex, the planning committee for the 2000 African American History Month Celebration Luncheon gather in the lobby. At the far left is Mack McKinney, chief, Programs Resources Management, who was chairperson for the event.

  18. 2000 African American History Month Celebration Luncheon

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Mack McKinney (left), chief, Programs Resources Management, and Delores Abraham (right), with the Astronaut office, flank one of the posters decorating the Early Space Exploration Conference Center at the KSC Visitor Complex for the 2000 African American History Month Celebration Luncheon. McKinney is chairperson for the event.

  19. African Higher Education: An International Reference Handbook.

    ERIC Educational Resources Information Center

    Teferra, Damtew, Ed.; Altbach, Philip G., Ed.

    This book is a comprehensive survey of all aspects and dimensions of higher education in Africa. It includes a historical overview of higher education, descriptions of the higher education systems in each African country, and analyses of current and timely topics in higher education. Part 1, "Themes," contains 13 essays on trends in…

  20. Violent Behaviors among African-American Adolescents.

    ERIC Educational Resources Information Center

    Garrett, Darhyl

    1995-01-01

    Explores the development of behaviors by using Erik Erikson's psychosocial developmental theory, with emphasis on adolescents. Examines factors, such as identity versus identity diffusion, that may be contributing to increasing acts of violence by African American adolescents. Other factors are examined that may contribute to increased violence.…

  1. African American Female Superintendents: Resilient School Leaders

    ERIC Educational Resources Information Center

    Johnson, Bernadeia H.

    2012-01-01

    Six African American female superintendents who had served as superintendents in at least 2 school districts were interviewed to understand ways in which they responded to barriers and adversity in their roles, with a particular emphasis on issues related to sexism and racism. Study participants shared that they work to engage the community and…

  2. African-American Males: Education or Incarceration.

    ERIC Educational Resources Information Center

    Green, Robert L.

    This paper analyzes the relationship between levels of educational attainment and outcomes for African American males, in particular the likelihood of conflict with the criminal justice system. The analysis begins with a look at society's belief system and political and economic forces, and argues that these have combined to promote failure among…

  3. Adult Illiteracy: The Root of African Underdevelopment

    ERIC Educational Resources Information Center

    Jogwu, C. N. O.

    2010-01-01

    All African Nations belong to the category of third world underdeveloped countries of the world. UNDP Human Development Index uses factors like per capita income, health of the people, and educational attainment to classify countries. Adult literacy and gross enrolment ratios are indicators of education status. This paper uses Nigeria, a typical…

  4. Promotive Parenting Practices among African American Mothers

    ERIC Educational Resources Information Center

    Williams-Wheeler, Meeshay

    2011-01-01

    The purpose of this study was to examine communication/reasoning, behavioral control, and trust as predictors of resourcefulness among African American children during middle childhood (6-12 years of age). Mothers who practice promotive socialization strategies are more likely to rear children who are socially competent and well adjusted. Multiple…

  5. Five Types of African-American Marriages.

    ERIC Educational Resources Information Center

    Allen, William D.; Olson, David H.

    2001-01-01

    Developed a marital typology based on a nonrandom, national sample of 415 African American couples who took the Enriching Relationship Issues, Communication and Happiness (ENRICH) marital assessment inventory. Five marriage types were labeled as vitalized; harmonious; traditional; conflicted; and devitalized. Results were similar to findings in…

  6. African Drum and Steel Pan Ensembles.

    ERIC Educational Resources Information Center

    Sunkett, Mark E.

    2000-01-01

    Discusses how to develop both African drum and steel pan ensembles providing information on teacher preparation, instrument choice, beginning the ensemble, and lesson planning. Includes additional information for the drum ensembles. Lists references and instructional materials, sources of drums and pans, and common note layout/range for steel pan…

  7. The African Experience with Higher Education.

    ERIC Educational Resources Information Center

    Ajayi, J. F. Ade; And Others

    This book covers the history and politics of higher education in Africa south of the Sahara, as well as contemporary issues, problems, and weaknesses of African universities. The need for a new look at the mission of the university in the 21st century is also addressed. Chapters cover the following topics: (1) higher education in Africa before…

  8. African American Homeschooling Practices: Empirical Evidence

    ERIC Educational Resources Information Center

    Mazama, Ama

    2016-01-01

    Despite a significant increase in scholarly interest for homeschooling, some of its most critical aspects, such as instructional daily practices, remain grossly understudied. This essay thus seeks to fill that void by presenting empirical evidence regarding the homeschooling practices of a specific group, African Americans. Most specifically, the…

  9. The landscape of recombination in African Americans

    PubMed Central

    Hinch, Anjali G.; Tandon, Arti; Patterson, Nick; Song, Yunli; Rohland, Nadin; Palmer, Cameron D.; Chen, Gary K.; Wang, Kai; Buxbaum, Sarah G.; Akylbekova, Meggie; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Boerwinkle, Eric; Cai, Qiuyin; Caporaso, Neil; Casey, Graham; Cupples, L. Adrienne; Deming, Sandra L.; Diver, W. Ryan; Divers, Jasmin; Fornage, Myriam; Gillanders, Elizabeth M.; Glessner, Joseph; Harris, Curtis C.; Hu, Jennifer J.; Ingles, Sue A.; Isaacs, Williams; John, Esther M.; Kao, W. H. Linda; Keating, Brendan; Kittles, Rick A.; Kolonel, Laurence N.; Larkin, Emma; Le Marchand, Loic; McNeill, Lorna H.; Millikan, Robert C.; Murphy, Adam; Musani, Solomon; Neslund-Dudas, Christine; Nyante, Sarah; Papanicolaou, George J.; Press, Michael F.; Psaty, Bruce M.; Reiner, Alex P.; Rich, Stephen S.; Rodriguez-Gil, Jorge L.; Rotter, Jerome I.; Rybicki, Benjamin A.; Schwartz, Ann G.; Signorello, Lisa B.; Spitz, Margaret; Strom, Sara S.; Thun, Michael J.; Tucker, Margaret A.; Wang, Zhaoming; Wiencke, John K.; Witte, John S.; Wrensch, Margaret; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A.; Zheng, Wei; Ziegler, Regina G.; Zhu, Xiaofeng; Redline, Susan; Hirschhorn, Joel N.; Henderson, Brian E.; Taylor, Herman A.; Price, Alkes L.; Hakonarson, Hakon; Chanock, Stephen J.; Haiman, Christopher A.; Wilson, James G.; Reich, David; Myers, Simon R.

    2011-01-01

    Recombination, together with mutation, is the ultimate source of genetic variation in populations. We leverage the recent mixture of people of African and European ancestry in the Americas to build a genetic map measuring the probability of crossing-over at each position in the genome, based on about 2.1 million crossovers in 30,000 unrelated African Americans. At intervals of more than three megabases it is nearly identical to a map built in Europeans. At finer scales it differs significantly, and we identify about 2,500 recombination hotspots that are active in people of West African ancestry but nearly inactive in Europeans. The probability of a crossover at these hotspots is almost fully controlled by the alleles an individual carries at PRDM9 (P<10−245). We identify a 17 base pair DNA sequence motif that is enriched in these hotspots, and is an excellent match to the predicted binding target of African-enriched alleles of PRDM9. PMID:21775986

  10. Tuberculosis Detection by Giant African Pouched Rats

    ERIC Educational Resources Information Center

    Poling, Alan; Weetjens, Bart; Cox, Christophe; Beyene, Negussie; Durgin, Amy; Mahoney, Amanda

    2011-01-01

    In recent years, operant discrimination training procedures have been used to teach giant African pouched rats to detect tuberculosis (TB) in human sputum samples. This article summarizes how the rats are trained and used operationally, as well as their performance in studies published to date. Available data suggest that pouched rats, which can…

  11. Prostate Cancer Genetics in African Americans

    DTIC Science & Technology

    2014-09-01

    receiving appropriate education, genetic counseling , and/or referral. During each interview the research coordinator identifies at risk family members...AD_________________ Award Number: W81XWH-11-1-0566 TITLE: Prostate Cancer Genetics in African...ADDRESS. 1. REPORT DATE 2. REPORT TYPE Annual 3. DATES COVERED 15 Aug 2013 – 14 Aug 2014 4. TITLE AND SUBTITLE Prostate Cancer Genetics in

  12. Caring School Leadership: A South African Study

    ERIC Educational Resources Information Center

    van der Vyver, Cornelius P.; van der Westhuizen, Philip C.; Meyer, L. W.

    2014-01-01

    The research pivoted on the question whether South African school principals fulfilled their caring role towards teachers. The aims of the study were threefold. First, to determine how principals rated their care-giving, secondly to determine whether significant discrepancies existed between principals' rating of their care-giving and teachers'…

  13. Endometrial polyps in 2 African pygmy hedgehogs.

    PubMed

    Phillips, Irene D; Taylor, Jacqueline J; Allen, Andrew L

    2005-06-01

    Reports of spontaneously occurring endometrial polyps in animals are rare and have only involved a few species. This report is intended to advise veterinarians that older African pygmy hedgehogs may develop endometrial polyps and that these lesions can be a cause of bloody vaginal discharge, sometimes interpreted as hematuria.

  14. African Trypanosomes Find a Fat Haven

    PubMed Central

    Beverley, Stephen M.

    2016-01-01

    The African trypanosome was thought to primarily develop in the bloodstream and interstitial spaces of its mammalian host. In this issue of Cell Host & Microbe, Trindade et al. (2016) report the surprising finding that during ongoing persistent infections in mice, a major fraction of the parasites reside within fatty tissues. PMID:27281564

  15. African Linguistics. Working Papers in Linguistics 19.

    ERIC Educational Resources Information Center

    University of Trondheim Working Papers in Linguistics, 1993

    1993-01-01

    Five papers on African linguistics are presented. "Observations on Some Derivational Affixes in Kiswahili Predicate Items" (Assibi Apatewon Amidu) examines the few morphemes recognized in the Swahili derivational affix system and suggests changes in the rules of vowel harmony and in presentation and representation of the affixes in use.…

  16. Legacy of a Pioneer African American Educator

    ERIC Educational Resources Information Center

    Cazers, Gunars; Curtner-Smith, Matthew

    2013-01-01

    Purpose: The purpose was to reconstruct the historical and legendary contribution of one exemplary African American physical education teacher educator who lived and worked in the Deep South prior to and immediately following the 1954 Brown v. Board of Education court case. The following questions guided data collection and analysis: To what…

  17. African Women in the Visual Arts.

    ERIC Educational Resources Information Center

    Aronson, Lisa

    1991-01-01

    Explores recent studies in anthropology, art history, and archeology on African women's art from a feminist theoretical perspective. Relates women's arts to several sociological and economic factors and suggests new avenues of exploration, especially in the face of urbanization and modernization. (CJS)

  18. The landscape of recombination in African Americans.

    PubMed

    Hinch, Anjali G; Tandon, Arti; Patterson, Nick; Song, Yunli; Rohland, Nadin; Palmer, Cameron D; Chen, Gary K; Wang, Kai; Buxbaum, Sarah G; Akylbekova, Ermeg L; Aldrich, Melinda C; Ambrosone, Christine B; Amos, Christopher; Bandera, Elisa V; Berndt, Sonja I; Bernstein, Leslie; Blot, William J; Bock, Cathryn H; Boerwinkle, Eric; Cai, Qiuyin; Caporaso, Neil; Casey, Graham; Cupples, L Adrienne; Deming, Sandra L; Diver, W Ryan; Divers, Jasmin; Fornage, Myriam; Gillanders, Elizabeth M; Glessner, Joseph; Harris, Curtis C; Hu, Jennifer J; Ingles, Sue A; Isaacs, William; John, Esther M; Kao, W H Linda; Keating, Brendan; Kittles, Rick A; Kolonel, Laurence N; Larkin, Emma; Le Marchand, Loic; McNeill, Lorna H; Millikan, Robert C; Murphy, Adam; Musani, Solomon; Neslund-Dudas, Christine; Nyante, Sarah; Papanicolaou, George J; Press, Michael F; Psaty, Bruce M; Reiner, Alex P; Rich, Stephen S; Rodriguez-Gil, Jorge L; Rotter, Jerome I; Rybicki, Benjamin A; Schwartz, Ann G; Signorello, Lisa B; Spitz, Margaret; Strom, Sara S; Thun, Michael J; Tucker, Margaret A; Wang, Zhaoming; Wiencke, John K; Witte, John S; Wrensch, Margaret; Wu, Xifeng; Yamamura, Yuko; Zanetti, Krista A; Zheng, Wei; Ziegler, Regina G; Zhu, Xiaofeng; Redline, Susan; Hirschhorn, Joel N; Henderson, Brian E; Taylor, Herman A; Price, Alkes L; Hakonarson, Hakon; Chanock, Stephen J; Haiman, Christopher A; Wilson, James G; Reich, David; Myers, Simon R

    2011-07-20

    Recombination, together with mutation, gives rise to genetic variation in populations. Here we leverage the recent mixture of people of African and European ancestry in the Americas to build a genetic map measuring the probability of crossing over at each position in the genome, based on about 2.1 million crossovers in 30,000 unrelated African Americans. At intervals of more than three megabases it is nearly identical to a map built in Europeans. At finer scales it differs significantly, and we identify about 2,500 recombination hotspots that are active in people of West African ancestry but nearly inactive in Europeans. The probability of a crossover at these hotspots is almost fully controlled by the alleles an individual carries at PRDM9 (P value < 10(-245)). We identify a 17-base-pair DNA sequence motif that is enriched in these hotspots, and is an excellent match to the predicted binding target of PRDM9 alleles common in West Africans and rare in Europeans. Sites of this motif are predicted to be risk loci for disease-causing genomic rearrangements in individuals carrying these alleles. More generally, this map provides a resource for research in human genetic variation and evolution.

  19. Prevalence of Stuttering in African American Preschoolers

    ERIC Educational Resources Information Center

    Proctor, Adele; Yairi, Ehud; Duff, Melissa C.; Zhang, Jie

    2008-01-01

    Purpose: In this study, the authors sought to determine the prevalence of stuttering in African American (AA) 2- to 5-year-olds as compared with same-age European Americans (EAs). Method: A total of 3,164 children participated: 2,223 AAs and 941 EAs. Data were collected using a 3-pronged approach that included investigators' individual…

  20. Myths in African Concept of Reality

    ERIC Educational Resources Information Center

    Jaja, Jones M.

    2014-01-01

    Myths are accounts of the origin of societies and institutions not subject to rationalization but often used by historians and philosophers in their quest to study African history; for it is only thus that we can comprehend the various aspects of the continent's history and culture. This paper examines the critical understanding of African…

  1. Cataloging the Pan-African Experience

    ERIC Educational Resources Information Center

    Hayes, Dianne

    2012-01-01

    Of all the honors and accolades bibliophile and noted authority on the Underground Railroad Charles Blockson has received, being bequeathed recently with some of Harriet Tubman's personal items by her great-niece is one of the most significant experiences of his life. A longtime collector of books and rare items by and about African-Americans,…

  2. African American Biographies: A Collection Development Challenge.

    ERIC Educational Resources Information Center

    Woody, Donna

    2000-01-01

    Discusses the lack of African American biographies for elementary school libraries and reports the results of a study that surveyed publishers from the Children's Book Council. Examines book reviews, discusses the number of sports figures included, and considers problems with a lack of appropriate materials to support the curriculum. (LRW)

  3. Language and the African American Child

    ERIC Educational Resources Information Center

    Green, Lisa J.

    2011-01-01

    How do children acquire African American English? How do they develop the specific language patterns of their communities? Drawing on spontaneous speech samples and data from structured elicitation tasks, this book explains the developmental trends in the children's language. It examines topics such as the development of tense/aspect marking,…

  4. The Persistence of African American College Men

    ERIC Educational Resources Information Center

    Beale, Tyson J.

    2010-01-01

    This study explored the family dynamics of persistent African American college men. These students were typical Black males, not those pre-categorized as high-achieving or unprepared for college. The stories of participants revealed their strength, ambition, and intentions to successfully gain a baccalaureate degree. In general Black males are…

  5. Dictionaries of African Sign Languages: An Overview

    ERIC Educational Resources Information Center

    Schmaling, Constanze H.

    2012-01-01

    This article gives an overview of dictionaries of African sign languages that have been published to date most of which have not been widely distributed. After an introduction into the field of sign language lexicography and a discussion of some of the obstacles that authors of sign language dictionaries face in general, I will show problems…

  6. Regenerating African Decayed Land: Can Reading Contribute?

    ERIC Educational Resources Information Center

    Biniakunu, Dianzungu Dia

    1991-01-01

    Relates how the publication of a book (written in Kikongo, an African native language) designed to raise peasants' awareness in Lower Zaire about desertification and other serious environmental issues had dramatic and surprising implications not only for the environment, but also regarding peasant literacy and the power of reading. (SR)

  7. Fat, fibre and cancer risk in African Americans and rural Africans.

    PubMed

    O'Keefe, Stephen J D; Li, Jia V; Lahti, Leo; Ou, Junhai; Carbonero, Franck; Mohammed, Khaled; Posma, Joram M; Kinross, James; Wahl, Elaine; Ruder, Elizabeth; Vipperla, Kishore; Naidoo, Vasudevan; Mtshali, Lungile; Tims, Sebastian; Puylaert, Philippe G B; DeLany, James; Krasinskas, Alyssa; Benefiel, Ann C; Kaseb, Hatem O; Newton, Keith; Nicholson, Jeremy K; de Vos, Willem M; Gaskins, H Rex; Zoetendal, Erwin G

    2015-04-28

    Rates of colon cancer are much higher in African Americans (65:100,000) than in rural South Africans (<5:100,000). The higher rates are associated with higher animal protein and fat, and lower fibre consumption, higher colonic secondary bile acids, lower colonic short-chain fatty acid quantities and higher mucosal proliferative biomarkers of cancer risk in otherwise healthy middle-aged volunteers. Here we investigate further the role of fat and fibre in this association. We performed 2-week food exchanges in subjects from the same populations, where African Americans were fed a high-fibre, low-fat African-style diet and rural Africans a high-fat, low-fibre western-style diet, under close supervision. In comparison with their usual diets, the food changes resulted in remarkable reciprocal changes in mucosal biomarkers of cancer risk and in aspects of the microbiota and metabolome known to affect cancer risk, best illustrated by increased saccharolytic fermentation and butyrogenesis, and suppressed secondary bile acid synthesis in the African Americans.

  8. Fat, Fiber and Cancer Risk in African Americans and Rural Africans

    PubMed Central

    O'Keefe, Stephen J.D.; Li, Jia V.; Lahti, Leo; Ou, Junhai; Carbonero, Franck; Mohammed, Khaled; Posma, Joram M; Kinross, James; Wahl, Elaine; Ruder, Elizabeth; Vipperla, Kishore; Naidoo, Vasudevan; Mtshali, Lungile; Tims, Sebastian; Puylaert, Philippe G.B.; DeLany, James; Krasinskas, Alyssa; Benefiel, Ann C.; Kaseb, Hatem O.; Newton, Keith; Nicholson, Jeremy K.; de Vos, Willem M.; Gaskins, H. Rex; Zoetendal, Erwin G.

    2015-01-01

    Rates of colon cancer are much higher in African Americans (65:100,000) than in rural South Africans (<5:100,000). The higher rates are associated with higher animal protein and fat and lower fiber consumption, higher colonic secondary bile acids, lower colonic short chain fatty acid quantities and higher mucosal proliferative biomarkers of cancer risk in otherwise healthy middle aged volunteers. Here we investigate further the role of fat and fiber in this association. We performed two-week food exchanges in subjects from the same populations, where African Americans were fed a high-fiber, lowfat African-style diet, and rural Africans a high-fat low-fiber western-style diet under close supervision. In comparison to their usual diets, the food changes resulted in remarkable reciprocal changes in mucosal biomarkers of cancer risk and in aspects of the microbiota and metabolome known to affect cancer risk, best illustrated by increased saccharolytic fermentation and butyrogenesis and suppressed secondary bile acid synthesis in the African Americans. PMID:25919227

  9. Managing the hair and skin of African American pediatric patients.

    PubMed

    Smith, W; Burns, C

    1999-01-01

    In Africa, the ancestral home of most African Americans, hair is viewed as the epitome of beauty. However, when Africans were brought to America as slaves, they were unable to care for their hair and skin adequately and were exposed to the predominant white culture, which valued straight hair and light skin. As a result, many African Americans lost self-esteem because of the characteristics of their hair and skin. In this article we examine the anatomic and physiologic features of African American hair and skin and typical African American hair and skin care practices. Common African American hair and skin disorders and their management are discussed. The goal of this article is to help primary care providers understand the special hair and skin care required for African American children (as well as other dark-skinned patients). With good patient education, understanding one's own hair and skin characteristics can also support positive self-esteem.

  10. Informing cancer prevention strategies for African Americans: the relationship of African American acculturation to fruit, vegetable, and fat intake.

    PubMed

    Ard, Jamy D; Skinner, Celette Sugg; Chen, Chuhe; Aickin, Mikel; Svetkey, Laura P

    2005-06-01

    Acculturation has been associated with health-related behaviors in African Americans. We sought to determine if there is a relationship between acculturation and dietary intake in African Americans. African Americans in the PREMIER trial completed the African American Acculturation Scale (AAAS) and 2 nonconsecutive 24-h dietary recalls (n = 238). Analysis of variance (ANOVA) and canonical correlation were used to assess relationships between acculturation and dietary intakes. Canonical correlation (p = 0.05) showed that traditional African Americans had lower intakes of fruits/vegetables and milk/dairy with higher intakes of fats, meat, and nuts. This pattern was supported by differences in the ANOVA. African American acculturation is related to dietary intake. These findings have implications for the design of cancer-related public health messages targeted to African Americans.

  11. Population affinities of African Colombians to Sub-Saharan Africans based on dental morphology.

    PubMed

    Delgado-Burbano, M E

    2007-01-01

    The Atlantic slave trade moved more than 13 million Africans to American lands between the 15th and 19th centuries. Previous historical, linguistic, and social-cultural studies suggested a Western-Central Bantu African origin for the Colombian slaves; however, their precise provenance remains unclear. The present study investigates the variation of the epigenetic dental traits in the deciduous and permanent dentition and phenotypic affinities of a contemporary Afro-Colombian community (n=178) in an attempt to identify their possible African ancestors. The results of a multivariate analysis of principal components show that Afro-descendents from Guapi have strong phenotypic relationships with several Bantu-speakers groups of Western and Western-Central Africa (Sub-Saharan region), specifically from Gabon, Congo, Pygmies, Nigeria, Cameroon, Togo and Benin. In concordance with recent mtDNA studies, this research suggests a distant but important relationship between Afro-Colombians and Eastern and South-Eastern African populations. This analysis also shows a marked dental divergence with North African samples. The dental information is not very different from the cultural, linguistic and historic data; however, it is more in agreement with studies based on molecular variation. In addition, this study reveals that African-Americans from North America, Central America-Caribbean and South America have high biological variation essentially identical to their several Sub-Saharan sources. Although a microevolutionary model, based on differential rates of gene flow with Native American and European-American groups and little selective pressures influence, better explains the phenotypic variation observed, more African-American dental samples must be analyzed from a regional perspective.

  12. Pan-African genetic structure in the African buffalo (Syncerus caffer): investigating intraspecific divergence.

    PubMed

    Smitz, Nathalie; Berthouly, Cécile; Cornélis, Daniel; Heller, Rasmus; Van Hooft, Pim; Chardonnet, Philippe; Caron, Alexandre; Prins, Herbert; van Vuuren, Bettine Jansen; De Iongh, Hans; Michaux, Johan

    2013-01-01

    The African buffalo (Syncerus caffer) exhibits extreme morphological variability, which has led to controversies about the validity and taxonomic status of the various recognized subspecies. The present study aims to clarify these by inferring the pan-African spatial distribution of genetic diversity, using a comprehensive set of mitochondrial D-loop sequences from across the entire range of the species. All analyses converged on the existence of two distinct lineages, corresponding to a group encompassing West and Central African populations and a group encompassing East and Southern African populations. The former is currently assigned to two to three subspecies (S. c. nanus, S. c. brachyceros, S. c. aequinoctialis) and the latter to a separate subspecies (S. c. caffer). Forty-two per cent of the total amount of genetic diversity is explained by the between-lineage component, with one to seventeen female migrants per generation inferred as consistent with the isolation-with-migration model. The two lineages diverged between 145 000 to 449 000 years ago, with strong indications for a population expansion in both lineages, as revealed by coalescent-based analyses, summary statistics and a star-like topology of the haplotype network for the S. c. caffer lineage. A Bayesian analysis identified the most probable historical migration routes, with the Cape buffalo undertaking successive colonization events from Eastern toward Southern Africa. Furthermore, our analyses indicate that, in the West-Central African lineage, the forest ecophenotype may be a derived form of the savanna ecophenotype and not vice versa, as has previously been proposed. The African buffalo most likely expanded and diverged in the late to middle Pleistocene from an ancestral population located around the current-day Central African Republic, adapting morphologically to colonize new habitats, hence developing the variety of ecophenotypes observed today.

  13. Pan-African Genetic Structure in the African Buffalo (Syncerus caffer): Investigating Intraspecific Divergence

    PubMed Central

    Smitz, Nathalie; Berthouly, Cécile; Cornélis, Daniel; Heller, Rasmus; Van Hooft, Pim; Chardonnet, Philippe; Caron, Alexandre; Prins, Herbert; van Vuuren, Bettine Jansen; De Iongh, Hans; Michaux, Johan

    2013-01-01

    The African buffalo (Syncerus caffer) exhibits extreme morphological variability, which has led to controversies about the validity and taxonomic status of the various recognized subspecies. The present study aims to clarify these by inferring the pan-African spatial distribution of genetic diversity, using a comprehensive set of mitochondrial D-loop sequences from across the entire range of the species. All analyses converged on the existence of two distinct lineages, corresponding to a group encompassing West and Central African populations and a group encompassing East and Southern African populations. The former is currently assigned to two to three subspecies (S. c. nanus, S. c. brachyceros, S. c. aequinoctialis) and the latter to a separate subspecies (S. c. caffer). Forty-two per cent of the total amount of genetic diversity is explained by the between-lineage component, with one to seventeen female migrants per generation inferred as consistent with the isolation-with-migration model. The two lineages diverged between 145 000 to 449 000 years ago, with strong indications for a population expansion in both lineages, as revealed by coalescent-based analyses, summary statistics and a star-like topology of the haplotype network for the S. c. caffer lineage. A Bayesian analysis identified the most probable historical migration routes, with the Cape buffalo undertaking successive colonization events from Eastern toward Southern Africa. Furthermore, our analyses indicate that, in the West-Central African lineage, the forest ecophenotype may be a derived form of the savanna ecophenotype and not vice versa, as has previously been proposed. The African buffalo most likely expanded and diverged in the late to middle Pleistocene from an ancestral population located around the current-day Central African Republic, adapting morphologically to colonize new habitats, hence developing the variety of ecophenotypes observed today. PMID:23437100

  14. SADCC: challenging the "South African connection.".

    PubMed

    Liebenow, J G

    1982-01-01

    The Southern African Development Coordination Conference (SADCC) which unites 9 states with a combined population of 60 million, has as its objective the task of promoting economic development and realizing economic independence. In many respects the strain of neocolonialism that Southern Africa faces at this time is even more virulent than that facing West, Central, and East Africa. In the latter regions the surrender of political authority by colonial administrators frequently left the commercial, agricultural, and industrial interests of the European powers in continued control of the economies of the former colonies. The fate of economic development plans was determined by situations and decisions made in places distant from the African continent. In the case of Southern Africa, the withdrawal or expulsion of European colonialists has found whites in neighboring South Africa most eager to step into the economic breech. For most of the Southern African states this variant strain of the neocolonial virus creates a dual problem: the independent states acting separately have been no match for South Africa; and the acquiescence of independent African states in forging economic links with South Africa has impeded the liberation efforts of Africans in Namibia and the Republic of South Africa. Discussion focus turns to the challenges that confront SADCC; transport as the most significant factor accounting for the dependency of SADCC states upon South Africa; the role of minerals in dependency; other aspects of dependency; South Africa's proposed Constellation of States; the origins and objectives of SADCC; and dollars and donors. SADCC planning for economic liberation has been conducted against the background of a counterproposal advanced by South Africa's government, which put the Republic at the center of an expanded network of economic linkages within the entire southern African region. While being formally rejected, the Constellation of States scheme does have

  15. Ectomycorrhizal symbiosis of tropical African trees.

    PubMed

    Bâ, Amadou M; Duponnois, Robin; Moyersoen, Bernard; Diédhiou, Abdala G

    2012-01-01

    The diversity, ecology and function of ectomycorrhizal (EM) fungi and ectomycorrhizas (ECMs) on tropical African tree species are reviewed here. While ECMs are the most frequent mycorrhizal type in temperate and boreal forests, they concern an economically and ecologically important minority of plants in African tropical forests. In these African tropical forests, ECMs are found mainly on caesalpionioid legumes, Sarcolaenaceae, Dipterocarpaceae, Asterpeiaceae, Phyllantaceae, Sapotaceae, Papilionoideae, Gnetaceae and Proteaceae, and distributed in open, gallery and rainforests of the Guineo-Congolian basin, Zambezian Miombo woodlands of East and South-Central Africa and Sudanian savannah woodlands of the sub-sahara. Overall, EM status was confirmed in 93 (26%) among 354 tree species belonging to EM genera. In addition, 195 fungal taxa were identified using morphological descriptions and sequencing of the ML5/ML6 fragment of sporocarps and ECMs from West Africa. Analyses of the belowground EM fungal communities mostly based on fungal internal transcribed spacer sequences of ECMs from Continental Africa, Madagascar and the Seychelles also revealed more than 350 putative species of EM fungi belonging mainly to 18 phylogenetic lineages. As in temperate forests, the /russula-lactarius and /tomentella-thelephora lineages dominated EM fungal flora in tropical Africa. A low level of host preference and dominance of multi-host fungal taxa on different African adult tree species and their seedlings were revealed, suggesting a potential for the formation of common ectomycorrhizal networks. Moreover, the EM inoculum potential in terms of types and density of propagules (spores, sclerotia, EM root fragments and fragments of mycelia strands) in the soil allowed opportunistic root colonisation as well as long-term survival in the soil during the dry season. These are important characteristics when choosing an EM fungus for field application. In this respect, Thelephoroid fungal sp

  16. A plea to better feed African soils

    NASA Astrophysics Data System (ADS)

    Stroosnijder, Leo

    2014-05-01

    Most African cropping system are rainfed. Rain is distributed at the soil surface over infiltration and runoff. The infiltrated water is stored in the rootable soil layer and the excess drains below that layer into the groundwater. The stored water is partly lost as evaporation to the atmosphere and partly used as transpiration for plant growth. In African cropping system the green water use efficiency (GWUE: fraction transpiration over rainfall) is as low as 15%. This low value is due to the often poor soil quality (physical, chemical and biological) of African soils. The poor physical state causes a weak soil structure resulting in crust formation with low infiltration and high runoff as consequences. The water holding capacity of the rootable soil layer is also poor, causing quite some water lost into deeper layers. African soils are poor due to long time soil mining. Soil life depends on soil organic matter (SOM) which is decreasing everywhere at an average rate of 2% per year. It is common sense that an improved soil quality is essential for improved food security. The key that triggers a sustainable improvement in soil quality is a system's approach that focus on the management of organic resources. Soil is a living organism, and it feeds on SOM. This feed is continuously consumed but a living soil makes new SOM out of fresh organic matter. In order to keep our soils alive we need cropping systems that feed our soils with fresh organic matter in the form of crop residues in the right mix of quality and quantity. The tendency to breed crops with a high harvest index (hence low straw) and the many other uses of crop residues (competing claims) with it recent use for bio-ethanol fabrication is disastrous for our living soils. If we continue to allow SOM to decrease, soil crusting and hard setting will increase with less end less water available for the production of green biomass. Lower available water will trigger a negative spiral with lower food security and

  17. Range and Frequency of Africanized Honey Bees in California (USA)

    PubMed Central

    Kono, Yoshiaki; Kohn, Joshua R.

    2015-01-01

    Africanized honey bees entered California in 1994 but few accounts of their northward expansion or their frequency relative to European honey bees have been published. We used mitochondrial markers and morphometric analyses to determine the prevalence of Africanized honeybees in San Diego County and their current northward progress in California west of the Sierra Nevada crest. The northernmost African mitotypes detected were approximately 40 km south of Sacramento in California’s central valley. In San Diego County, 65% of foraging honey bee workers carry African mitochondria and the estimated percentage of Africanized workers using morphological measurements is similar (61%). There was no correlation between mitotype and morphology in San Diego County suggesting Africanized bees result from bidirectional hybridization. Seventy percent of feral hives, but only 13% of managed hives, sampled in San Diego County carried the African mitotype indicating that a large fraction of foraging workers in both urban and rural San Diego County are feral. We also found a single nucleotide polymorphism at the DNA barcode locus COI that distinguishes European and African mitotypes. The utility of this marker was confirmed using 401 georeferenced honey bee sequences from the worldwide Barcode of Life Database. Future censuses can determine whether the current range of the Africanized form is stable, patterns of introgression at nuclear loci, and the environmental factors that may limit the northern range of the Africanized honey bee. PMID:26361047

  18. In vitro permeation of platinum through African and Caucasian skin.

    PubMed

    Franken, A; Eloff, F C; du Plessis, J; Badenhorst, C J; Du Plessis, J L

    2015-02-03

    The majority of the South African workforce are Africans, therefore potential racial differences should be considered in risk and exposure assessments in the workplace. Literature suggests African skin to be a superior barrier against permeation and irritants. Previous in vitro studies on metals only included skin from Caucasian donors, whereas this study compared the permeation of platinum through African and Caucasian skin. A donor solution of 0.3 mg/ml of potassium tetrachloroplatinate (K₂PtCl₄) dissolved in synthetic sweat was applied to the vertical Franz diffusion cells with full thickness abdominal skin. Skin from three female African and three female Caucasian donors were included (n=21). The receptor solution was removed at various intervals during the 24 h experiment, and analysed with high resolution inductively coupled plasma-mass spectrometry (ICP-MS). Skin was digested and analysed by inductively coupled plasma-optical emission spectrometry (ICP-OES). Significantly higher permeation of platinum through intact African skin (p=0.044), as well as a significantly higher mass of platinum retention in African skin in comparison with Caucasian skin (p=0.002) occurred. Significant inter-donor variation was found in both racial groups (p<0.02). Results indicate that African workers have increased risk of dermal permeation and therefore possible sensitisation caused by dermal exposure to platinum salts. These results are contradictory to limited literature suggesting a superior barrier in African skin and further investigation is necessary to explain the higher permeation through African skin.

  19. Range and Frequency of Africanized Honey Bees in California (USA).

    PubMed

    Kono, Yoshiaki; Kohn, Joshua R

    2015-01-01

    Africanized honey bees entered California in 1994 but few accounts of their northward expansion or their frequency relative to European honey bees have been published. We used mitochondrial markers and morphometric analyses to determine the prevalence of Africanized honeybees in San Diego County and their current northward progress in California west of the Sierra Nevada crest. The northernmost African mitotypes detected were approximately 40 km south of Sacramento in California's central valley. In San Diego County, 65% of foraging honey bee workers carry African mitochondria and the estimated percentage of Africanized workers using morphological measurements is similar (61%). There was no correlation between mitotype and morphology in San Diego County suggesting Africanized bees result from bidirectional hybridization. Seventy percent of feral hives, but only 13% of managed hives, sampled in San Diego County carried the African mitotype indicating that a large fraction of foraging workers in both urban and rural San Diego County are feral. We also found a single nucleotide polymorphism at the DNA barcode locus COI that distinguishes European and African mitotypes. The utility of this marker was confirmed using 401 georeferenced honey bee sequences from the worldwide Barcode of Life Database. Future censuses can determine whether the current range of the Africanized form is stable, patterns of introgression at nuclear loci, and the environmental factors that may limit the northern range of the Africanized honey bee.

  20. Distinguishing African and European honeybee matrilines using amplified mitochondrial DNA.

    PubMed Central

    Hall, H G; Smith, D R

    1991-01-01

    Previous DNA studies have revealed that feral neotropical African bees have largely retained an African genetic integrity. Additional DNA testing is needed to confirm these findings, to understand the processes responsible, and to follow African bee spread into the temperate United States. To facilitate surveys, the polymerase chain reaction was utilized. African and European honeybee mitochondrial DNA (mtDNA) was identified through amplified segments that carry informative restriction site and length polymorphisms. The ability to discriminate among honeybee subspecies was established by testing a total of 129 colonies from Africa and Europe. Matriline identities could thus be determined for imported New World bees. Among 41 managed and feral colonies in the United States and north Mexico, two European lineages (west and east) were distinguished. From neotropical regions, 72 feral colonies had African mtDNA and 4 had European mtDNA. The results support earlier conclusions that neotropical African bees have spread as unbroken African maternal lineages. Old and New World African honeybee populations exhibit different frequencies of a mtDNA length polymorphism. Through standard analyses, a north African mtDNA type that may have been imported previously from Spain or Portugal was not detected among neotropical African bees. Images PMID:1674608

  1. Hematopoietic SCT for the Black African and non-Black African variants of sickle cell anemia.

    PubMed

    Lucarelli, G; Isgrò, A; Sodani, P; Marziali, M; Gaziev, J; Paciaroni, K; Gallucci, C; Cardarelli, L; Ribersani, M; Alfieri, C; De Angelis, G; Armiento, D; Andreani, M; Testi, M; Amato, A; Akinyanju, O O; Wakama, T T

    2014-11-01

    Sickle cell anemia (SCA) remains associated with high risks of morbidity and early death. Allogeneic hematopoietic SCT (HSCT) is the only curative treatment for SCA. We report our experience with transplantation in a group of patients with the non-Black African variant and the Black African variant of SCA. This study included 40 consecutive SCA patients (13 patients with the non-Black African variant and 27 with the Black African variant) who underwent BM transplantation from HLA-identical sibling donors between June 2004 and May 2013, following a myeloablative-conditioning regimen. All patients obtained sustained engraftment. One patient (non-Black African variant) became a stable mixed chimera with 25% donor cells more than 6 years after transplantation. The probabilities of survival, SCA-free survival and TRM at 5 years after transplant were 91%, 91% and 9%, respectively. All surviving patients remained free of any SCA-related events after transplantation. Our results confirm that it is possible to offer a greater than 90% chance of cure to children with SCA. HSCT should be considered the standard of care for who have an HLA-identical donor, before complications result from the sickling of RBC.

  2. Young Africans Tackle Their Continent's Environmental Issues

    NASA Astrophysics Data System (ADS)

    Olwoch, Jane Mukarugwiza

    2008-11-01

    Young African Scientists Session at the Fourth International Geosphere-Biosphere Programme Congress; Cape Town, South Africa, 7 May 2008; Africa is often described as a unique and diverse continent. This is reflected in its biodiversity, economic and social circumstances, and diversity in culture and environment. The Young African Scientists (YAS) session at the International Geosphere-Biosphere Programme Congress was one of the congress's highlights. Global environmental change research in Africa was presented to an audience that included visiting international and national scientists, policy makers, and a group of schoolchildren. From the uniqueness of Africa's paleoclimate to the diversity and complexity of current and future impacts of environmental change on Africa, the session not only provided an overview of current projects but also highlighted the problems that are intertwined with poverty. This session was sponsored by the Global Change System for Analysis, Research, and Training (START).

  3. Bushmeat hunting changes regeneration of African rainforests

    PubMed Central

    Effiom, Edu O.; Nuñez-Iturri, Gabriela; Smith, Henrik G.; Ottosson, Ulf; Olsson, Ola

    2013-01-01

    To assess ecological consequences of bushmeat hunting in African lowland rainforests, we compared paired sites, with high and low hunting pressure, in three areas of southeastern Nigeria. In hunted sites, populations of important seed dispersers—both small and large primates (including the Cross River gorilla, Gorilla gorilla diehli)—were drastically reduced. Large rodents were more abundant in hunted sites, even though they are hunted. Hunted and protected sites had similar mature tree communities dominated by primate-dispersed species. In protected sites, seedling communities were similar in composition to the mature trees, but in hunted sites species with other dispersal modes dominated among seedlings. Seedlings emerging 1 year after clearing of all vegetation in experimental plots showed a similar pattern to the standing seedlings. This study thus verifies the transforming effects of bushmeat hunting on plant communities of tropical forests and is one of the first studies to do so for the African continent. PMID:23516245

  4. Heat flow from the West African shield

    SciTech Connect

    Brigaud, F.; Lucazeau, F.; Ly, S.; Sauvage, J.F.

    1985-09-01

    The heat flow over Precambrian shields is generally lower than over other continental provinces. Previous observations at 9 sites of the West African shield have shown that heat flow ranges from 20 mW m/sup -2/ in Niger to 38-42 mW m/sup -2/ in Liberia, Ghana and Nigeria. Since some of these values are lower than expected for Precambrian shields, it is important to find out whether or not they are representative of the entire shield before trying to derive its thermal structure. In this paper, we present new heat flow determinations from seven sites of the West African shield. These indicate that the surface heat flow is comparable with that of other Precambrian shields in the world.

  5. Postpartum depression among African-American women.

    PubMed

    Amankwaa, Linda Clark

    2003-01-01

    The purpose of this qualitative study was to describe the nature of postpartum depression (PPD) among African-American women. Twelve women, who had experienced PPD within the last three years, were interviewed for approximately one hour at two intervals. Nudist-4 software and the constant comparative method were used to analyze the data. Five themes "Stressing Out," "Feeling Down," "Losing It," "Seeking Help," and "Feeling Better" represented aspects of PPD as experienced by the participants. The last theme, "Dealing with It," represented the cultural ways in which African-American mothers managed their depression. These included Keeping the Faith, Trying to Be a Strong Black Woman, Living with Myths, and Keeping Secrets. Suggestions for future directions in nursing research are included.

  6. A Regime Legitimacy Explanation of African Peacekeeping

    DTIC Science & Technology

    2011-09-01

    peacekeeping in a U-shaped curve, meaning that states attempting to increase their legitimacy participate at a higher-than-expected level. Likewise, the...distribution is unlimited A REGIME LEGITIMACY EXPLANATION OF AFRICAN PEACEKEEPING Matthew Ross Second Lieutenant, United States Air Force...B.S., Political Science, United States Air Force Academy, 2010 Submitted in partial fulfillment of the requirements for the degree of

  7. Prostate Cancer Genetics in African Americans

    DTIC Science & Technology

    2013-09-01

    grant from the U.S. Department of Defense to study the role heredity plays in prostate cancer among African Americans. "Prostate cancer is the...visit our website at: www.creighton.edu. Creighton gets grant to study heredity -cancer link - Houston Chronicle Coogle offers Google Offers Deals on...traffic Nahan & world Politics Health News bizarre Deaths Hurncanes Creighton gets grant to study heredity -cancer link Published 04 :40a.m., Monday

  8. Seasonal distribution of African savanna fires

    NASA Technical Reports Server (NTRS)

    Cahoon, Donald R., Jr.; Stocks, Brian J.; Levine, Joel S.; Cofer, Wesley R., III; O'Neill, Katherine P.

    1992-01-01

    The temporal and spatial distribution of savanna fires over the entire African continent, as determined from nighttime satellite imagery, is described. It is found that, contrary to expectations, most fires are left to burn uncontrolled, so that there is no strong diurnal cycle in the fire frequency. The knowledge gained from this study regarding the distribution and variability of fires is helpful in the monitoring of climatically important trace gases emitted from burning biomass.

  9. African swine fever: an epidemiological update.

    PubMed

    Sánchez-Vizcaíno, J M; Mur, L; Martínez-López, B

    2012-03-01

    African swine fever (ASF) is one of the most important swine diseases, mainly because of its significant sanitary and socioeconomic consequences. This review gives an update on the epidemiology of the disease and reviews key issues and strategies to improve control of the disease and promote its eradication. Several characteristics of ASF virus (ASFV) make its control and eradication difficult, including the absence of available vaccines, marked virus resistance in infected material and contaminated animal products, and a complex epidemiology and transmission involving tick reservoir virus interactions. The incidence of ASF has not only increased on the African continent over the last 15 years, so that it now affects West African countries, Mauritius and Madagascar, but it has also reached new areas, such as the Caucasus region in 2007. In fact, the rapid spread of the disease on the European continent and the uncontrolled situation in the Russian Federation places all countries at great risk as a result of intense global trade. The proximity of some affected areas to the European Union (EU) borders (<150 km) has increased concerns about the potential economic consequences of an ASF incursion into the EU pig sector. Establishing effective surveillance, control and eradication programmes that implicate all actors (veterinarians, farmers, and policy makers) is essential for controlling ASF. African swine fever -free countries should be aware of the potential risk of ASF incursion and implement risk reduction measures such as trade controls and other sanitary measures. This review will discuss lessons learnt so far about ASF control, current challenges to its control and future studies needed to support global efforts at prevention and control.

  10. Africans in the American Labor Market.

    PubMed

    Elo, Irma T; Frankenberg, Elizabeth; Gansey, Romeo; Thomas, Duncan

    2015-10-01

    The number of migrants to the United States from Africa has grown exponentially since the 1930s. For the first time in America's history, migrants born in Africa are growing at a faster rate than migrants from any other continent. The composition of African-origin migrants has also changed dramatically: in the mid-twentieth century, the majority were white and came from only three countries; but today, about one-fifth are white, and African-origin migrants hail from across the entire continent. Little is known about the implications of these changes for their labor market outcomes in the United States. Using the 2000-2011 waves of the American Community Survey, we present a picture of enormous heterogeneity in labor market participation, sectoral choice, and hourly earnings of male and female migrants by country of birth, race, age at arrival in the United States, and human capital. For example, controlling a rich set of human capital and demographic characteristics, some migrants-such as those from South Africa/Zimbabwe and Cape Verde, who typically enter on employment visas-earn substantial premiums relative to other African-origin migrants. These premiums are especially large among males who arrived after age 18. In contrast, other migrants-such as those from Sudan/Somalia, who arrived more recently, mostly as refugees-earn substantially less than migrants from other African countries. Understanding the mechanisms generating the heterogeneity in these outcomes-including levels of socioeconomic development, language, culture, and quality of education in countries of origin, as well as selectivity of those who migrate-figures prominently among important unresolved research questions.

  11. Africans in the American Labor Market

    PubMed Central

    Elo, Irma T.; Frankenberg, Elizabeth; Gansey, Romeo; Thomas, Duncan

    2015-01-01

    The number of migrants to the United States from Africa has grown exponentially since the 1930s. For the first time in America’s history, migrants born in Africa are growing at a faster rate than migrants from any other continent. The composition of African-origin migrants has also changed dramatically: in the mid-twentieth century, the majority were white and came from only three countries; but today, about one-fifth are white, and African-origin migrants hail from across the entire continent. Little is known about the implications of these changes for their labor market outcomes in the United States. Using the 2000–2011 waves of the American Community Survey, we present a picture of enormous heterogeneity in labor market participation, sectoral choice, and hourly earnings of male and female migrants by country of birth, race, age at arrival in the United States, and human capital. For example, controlling a rich set of human capital and demographic characteristics, some migrants—such as those from South Africa/Zimbabwe and Cape Verde, who typically enter on employment visas—earn substantial premiums relative to other African-origin migrants. These premiums are especially large among males who arrived after age 18. In contrast, other migrants—such as those from Sudan/Somalia, who arrived more recently, mostly as refugees—earn substantially less than migrants from other African countries. Understanding the mechanisms generating the heterogeneity in these outcomes—including levels of socioeconomic development, language, culture, and quality of education in countries of origin, as well as selectivity of those who migrate—remain important unresolved research questions. PMID:26304845

  12. Intraspinal tumours in the Kenya African.

    PubMed

    Ruberti, R F; Carmagnani, A L

    1976-06-01

    Thirty-one cases of intraspinal tumours in the African have been described, with age, sex incidence, frequency, site and histopathology shown. Intraspinal tumours in this series are compared with the larger series. Extradural and intramedullary tumours together with cervical spine tumours appear to be more frequent in this series. There is a high incidence of dumbell tumours in the neurinomas. Sarcomas are the most common type of tumours and mainly affect the thoracic spine.

  13. Malignant lymphoma in african lions (panthera leo).

    PubMed

    Harrison, T M; McKnight, C A; Sikarskie, J G; Kitchell, B E; Garner, M M; Raymond, J T; Fitzgerald, S D; Valli, V E; Agnew, D; Kiupel, M

    2010-09-01

    Malignant lymphoma has become an increasingly recognized problem in African lions (Panthera leo). Eleven African lions (9 male and 2 female) with clinical signs and gross and microscopic lesions of malignant lymphoma were evaluated in this study. All animals were older adults, ranging in age from 14 to 19 years. Immunohistochemically, 10 of the 11 lions had T-cell lymphomas (CD3(+), CD79a(-)), and 1 lion was diagnosed with a B-cell lymphoma (CD3(-), CD79a(+)). The spleen appeared to be the primary site of neoplastic growth in all T-cell lymphomas, with involvement of the liver (6/11) and regional lymph nodes (5/11) also commonly observed. The B-cell lymphoma affected the peripheral lymph nodes, liver, and spleen. According to the current veterinary and human World Health Organization classification of hematopoietic neoplasms, T-cell lymphoma subtypes included peripheral T-cell lymphoma (4/11), precursor (acute) T-cell lymphoblastic lymphoma/leukemia (2/11), chronic T-cell lymphocytic lymphoma/leukemia (3/11), and T-zone lymphoma (1/11). The single B-cell lymphoma subtype was consistent with diffuse large B-cell lymphoma. Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) testing by immunohistochemistry on sections of malignant lymphoma was negative for all 11 lions. One lion was seropositive for FeLV. In contrast to domestic and exotic cats, in which B-cell lymphomas are more common than T-cell lymphomas, African lions in this study had malignant lymphomas that were primarily of T-cell origin. Neither FeLV nor FIV, important causes of malignant lymphoma in domestic cats, seems to be significant in the pathogenesis of malignant lymphoma in African lions.

  14. Exploration of Depressive Symptoms in African American Cancer Patients

    PubMed Central

    Zhang, Amy Y.; Gary, Faye; Zhu, Hui

    2016-01-01

    Background Accurately assessing depression in African American cancer patients is difficult because of the similarities of physical symptoms observed in cancer and depression. Aim To identify universal and distinctive depressive symptoms in African American cancer patients. Methods Seventy-four cancer patients (34 depressed and 23 nondepressed African Americans, and 17 depressed Whites) were interviewed. Qualitative and quantitative analyses were conducted. Results Compared to nondepressed African Americans, depressed African Americans reported irritability, social isolation, insomnia, fatigue, and crying (p ≤ .05) more frequently over time. Compared to depressed Whites, they reported sadness, frustration, and intrusive thoughts less frequently (p ≤ .05), but insomnia and fatigue more frequently (p ≤ .05) during cancer treatment. There was little racial difference at the time of interview. Conclusion Depressed African American cancer patients may benefit from more culturally sensitive depression measures that consider symptoms of irritability, social isolation, and altered expressions of depressive mood. PMID:25564890

  15. Variables affecting racial-identity salience among African Americans.

    PubMed

    Thompson, V L

    1999-12-01

    The author clarified the African American racial-group identification process by addressing the issue of salience and its relationship to racial-group attitudes. A sample of 409 African American adults responded to surveys pertaining to their racial-group salience, racial-group attitudes, racial socialization, racial-group interaction, political activism, experiences of discrimination, and demographic data (e.g., sex, age, and income). The author tested 3 hypotheses: (a) Racial socialization and interaction with other African Americans are predictive of African American racial-identity salience; (b) discriminatory experiences are predictive of African American racial-identity salience; and (c) racial-identity salience is a stronger predictor of African American racial-group identification than are previously identified predictive variables (D. H. Demo & H. Hughes, 1990; V. L. Thompson Sanders, 1991, 1995). The results supported the 1st and 3rd hypotheses.

  16. Some growth points in African child development research.

    PubMed

    Serpell, Robert; Marfo, Kofi

    2014-01-01

    We reflect on ways in which research presented in earlier chapters responds to challenges of generating an African child development field and identify additional issues calling for the field's attention. The chapters collectively display a variety of African contexts and reflexive evidence of the authors' African cultural roots. Connecting research with African audiences demands cooperative communication between educational practitioners and parents with low literacy, and cross-sector communication among professionals. Intracultural exploration of factors influencing the pattern of human development has begun to document the potential of indigenous African cultures as a fund of resources for enhancing child development. Priority topics for future African developmental research include multilingualism, musical performance, socially distributed caregiving, and the relation between adolescence and economic activity. Integration of multiple disciplines in the application of research-based principles to service delivery in the fields of community-based (re)habilitation and early childhood care and education calls for researcher collaboration with practitioners.

  17. The topology of African exports: Emerging patterns on spanning trees

    NASA Astrophysics Data System (ADS)

    Araújo, Tanya; Ferreira, Manuel Ennes

    2016-11-01

    This paper is a contribution to interweaving two lines of research that have progressed in separate ways: network analysis of international trade and the literature on African trade and development. Gathering empirical data on African countries has important limitations and so does the space occupied by African countries in the analysis of trade networks. Here, these limitations are dealt with by the definition of two independent bipartite networks: a destination share network and a commodity share network. These networks-together with their corresponding minimal spanning trees-allow to uncover some ordering emerging from African exports in the broader context of international trade. The emerging patterns help to understand important characteristics of African exports and its binding relations to other economic, geographic and organizational concerns as the recent literature on African trade, development and growth has shown.

  18. Nutritional consequences of the African diaspora.

    PubMed

    Luke, A; Cooper, R S; Prewitt, T E; Adeyemo, A A; Forrester, T E

    2001-01-01

    Along with their foods and dietary customs, Africans were carried into diaspora throughout the Americas as a result of the European slave trade. Their descendants represent populations at varying stages of the nutrition transition. West Africans are in the early stage, where undernutrition and nutrient deficiencies are prevalent. Many Caribbean populations represent the middle stages, with undernutrition and obesity coexisting. African-Americans and black populations in the United Kingdom suffer from the consequences of caloric excess and diets high in fat and animal products. Obesity, non-insulin-dependent diabetes mellitus, hypertension, coronary heart disease, and certain cancers all follow an east-to-west gradient of increasing prevalence. Public health efforts must focus not only on eradicating undernutrition in West Africa and the Caribbean but also on preventing obesity, hypercholesterolemia, and their consequences. Fortunately, a coherent and well-supported set of recommendations exists to promote better nutrition. Implementation of it founders primarily as a result of the influence of commercial and political interests.

  19. African American teen mothers' perceptions of parenting.

    PubMed

    Wayland, J; Rawlins, R

    1997-02-01

    The purpose of this study was to describe the childbearing African American teens' perceptions of parenting based on their own experiences. Focus group discussions were held with 17 teens in their school setting for 50 minutes each week. Group discussions were audiotaped, tapes were transcribed, and then analyzed for common themes. The unmarried teens ranged in age from 15 to 18 years. Findings indicated that the teens depended on grandmothers to provide child care and for information about parenting. The teens identified parenting problems including crying, discipline, and conflicts dealing with grandmothers and the child's father. Teens wanted more information about breastfeeding and minor childhood diseases. The researchers identified that teens lacked information about their children's growth and development and safety issues. Findings have implications for nurses who care for childbearing teens and their children; and those involved in planning and implementing parent education programs for African American teen mothers and their families. Further research is indicated with larger samples of African American teens; and to explore the context of family relationships in which teen mothers and grandmothers share parenting for the teens' children.

  20. Rethinking "relevance": South African psychology in context.

    PubMed

    Long, Wahbie

    2013-02-01

    This article examines the phenomenon known as the "relevance debate" in South African psychology. It begins with a historical overview of the contours of the discipline in that country before describing the controversy's international dimensions, namely, the revolutionary politics of 1960s higher education and the subsequent emergence of cognate versions of the debate in American, European, and "Third World" psychology. The article then details how South Africa's "relevance" project enjoyed a special affinity with an assortment of ethnic-cultural, national, and continental myths and metaphors, all of which served the interests of the political formations of the day. It discusses how, in present-day South Africa, the intelligentsia has become an important catalyst for the so-called African Renaissance, which seeks to provide "relevant" solutions for the regeneration of African society. However, the global hegemony of what began in the 1970s as a "second academic revolution," aided by the lifting of the academic boycott of South Africa, has blunted the once critical edge of "relevance" discourse. A new mode of knowledge production now holds sway, the outcome of a dramatic reformulation of the capitalist manifesto in which the values of the "May 68" generation have been hijacked by a managerialist rationality. In light of the capitalization of the knowledge-production enterprise, it is concluded that the idiom of "relevance" has outlived its usefulness.