Sedimentation survey of Lago Cerrillos, Ponce, Puerto Rico, April-May 2008

USGS Publications Warehouse

Soler-López, Luis R.

2011-01-01

Lago Cerrillos dam, located in the municipality of Ponce in southern Puerto Rico, was constructed in 1991 as part of the multipurpose Rio Portugues and Bucana Project. This project provides flood protection, water supply, and recreation facilities for the municipio of Ponce. The reservoir had an original storage capacity of 38.03 million cubic meters at maximum conservation pool elevation of 174.65 meters above mean sea level and a drainage area of 45.32 square kilometers. Sedimentation in Lago Cerrillos reservoir has reduced the storage capacity from 38.03 million cubic meters in 1991 to 37.26 million cubic meters in 2008, which represents a total storage loss of about 2 percent. During July 29 to August 23, 2002, 8,492 cubic meters of sediment were removed from the Rio Cerrillos mouth of the reservoir. Taking into account this removed material, the total water-storage loss as of 2008 is 778,492 cubic meters, and the long-term annual water-storage capacity loss rate is about 45,794 cubic meters per year or about 0.12 percent per year. The Lago Cerrillos net sediment-contributing drainage area has an average sediment yield of about 1,069 cubic meters per square kilometer per year. Sediment accumulation in Lago Cerrillos is not uniformly distributed and averages about 3 meters in thickness. This represents a sediment deposition rate of about 18 centimeters per year. On the basis of the 2008 reservoir storage capacity of 37.26 million cubic meters per year and a long-term sedimentation rate of 45,794 cubic meters per year, Lago Cerrillos is estimated to have a useful life of about 814 years or until the year 2822.

Sedimentation Survey of Lago Toa Vaca, Puerto Rico, June-July 2002

USGS Publications Warehouse

Soler-López, Luis R.

2004-01-01

The Lago Toa Vaca dam is located in the municipality of Villalba in southern Puerto Rico, and is owned and operated by the Puerto Rico Aqueduct and Sewer Authority. Construction was completed in 1972 as the first phase of a multi-purpose project that contemplated four possible diversions from other basins to mitigate the rapid storage capacity loss of Lago Guayabal, located immediately downstream of the Toa Vaca dam. The latter phases of the intra-basin diversions were cancelled, and currently, the reservoir receives runoff from only 56.8 square kilometers of its drainage area. Lago Toa Vaca reservoir when constructed was to be used for irrigation of croplands in the southern coastal plain. The reservoir had an original storage capacity of 68.94 million cubic meters. Sedimentation has reduced the storage capacity by only 7 percent between 1972 and 2002 to 64.08 million cubic meters. This represents a long-term sedimentation rate of about 162,000 cubic meters per year. Based on the 2002 sedimentation survey, Lago Toa Vaca has a sediment trapping efficiency of about 98 percent and a drainage area-normalized sedimentation rate of about 3,086 cubic meters per square kilometer per year between 1972 and 2002. At the current long-term sedimentation rate the reservoir would lose its storage capacity by the year 2400.

Sedimentation History of Lago Guayabal, Puerto Rico, 1913-2001

USGS Publications Warehouse

Soler-López, Luis R.

2003-01-01

The Lago Guayabal dam, located in the municipality of Villalba in southern Puerto Rico, was constructed in 1913 for irrigation of croplands in the southern coastal plains and is owned and operated by the Puerto Rico Electric Power Authority. The reservoir had an original storage capacity of 11.82 million cubic meters and a drainage area upstream of the dam of 112 square kilometers. Sedimentation has reduced the storage capacity to 6.12 million cubic meters in 2001, which represents a storage loss of about 48 percent. However, the actual sediment accumulation in the reservoir during the 88 years is greater, because some sediment removal was conducted between 1940 and 1948 by dredging and sluicing. This report summarizes the historical data from a 1913 land survey and eight bathymetric surveys conducted between 1914 and 2001, and the relation of high sedimentation to agricultural land practices within the Lago Guayabal basin and six major hurricanes which made landfall on the island. The reservoir had an area-normalized sedimentation rate of about 1,863 cubic meters per square kilometer per year between 1913 and 1936 from a 112 square kilometer basin. In 1972, a new dam upstream along the Rio Toa Vaca impounded runoff from 57.5 square kilometers, and sediment transport to Lago Guayabal was reduced. A comparison of bathymetric survey results between 1972 and 2001 indicates an area-normalized sedimentation rate of 1,120 cubic meters per square kilometer per year or about 60 percent of the rate between 1913 and 1936. The significant reduction (almost half) of the sedimentation rate after the Toa Vaca dam was built may indicate that erosion susceptibility of the Rio Toa Vaca watershed is about twice that of the Rio Jacaguas watershed impounded by Lago Guayabal.

Public-private mix for TB and TB-HIV care in Lagos, Nigeria.

PubMed

Daniel, O J; Adedeji Adejumo, O; Abdur-Razzaq, H A; Ngozi Adejumo, E; Salako, A A

2013-09-01

Private and public tuberculosis (TB) treatment centres in Lagos State, Nigeria. To assess the contribution of private health care providers to TB and TB-HIV (human immunodeficiency virus) case finding in Lagos State. A retrospective review of programme data submitted to the Lagos State TB and Leprosy Control Programme in 2011 by public, private for-profit (PFP) and private not-for-profit (PNFP) health care providers. A total of 8425 TB cases were notified by 31 private (11 PFP and 20 PNFP) and 99 public health facilities in Lagos State. Overall, the private facilities were responsible for 10.3% (866/8425) of the total TB cases notified. The proportion of TB patients tested for HIV was respectively 86.2%, 53.1% and 96.5% among public, PFP and PNFP facilities. Overall, 22.4% of the TB patients were HIV-positive. The HIV positivity rate among public, PFP and PNFP facilities was respectively 23.8%, 7.8% and 9.9%. Uptake of cotrimoxazole preventive therapy was respectively 69.6%, 25% and 38.2% among public, PFP and PNFP facilities, while that of antiretroviral therapy was respectively 23.8%, 8.3% and 9.1% in public, PFP and PNFP facilities. There is a need to scale up collaboration with the private sector, and particularly PNFP health providers.

El Sistema de Referencia Celeste convencional de la IAU

NASA Astrophysics Data System (ADS)

Arias, E. F.

La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste baricéntrico cuyo plano fundamental y origen de ascensiones rectas estén próximos, respectivamente, al ecuador y equinoccio dinámicos J2000.0. El nuevo sistema de referencia estará materializado por las posiciones J2000.0 de radiofuentes extragalácticas determinadas con la técnica de interferometría de larga línea de base (VLBI). El Working Group on Reference Frames de la IAU (WGRF) decidió adoptar (Grasse, 1995) al sistema de referencia celeste extragaláctico del Servicio Internacional de la Rotación Terrestre (IERS) como futuro sistema de referencia celeste convencional bajo el nombre International Celestial Reference System (ICRS) y encomendó su mantenimiento futuro al IERS. El marco de referencia que materializará al ICRS contiene posiciones precisas J2000.0 de más de 600 radiofuentes extragalácticas. Las coordenadas fueron ajustadas en una única solución VLBI en la cual se incluyeron todas las observaciones realizadas hasta octubre de 1995 con la técnica de adquisición de datos VLBI Mark III. Para minimizar los errores sistemáticos que pueden afectar la calidad del marco de referencia se introdujeron mejoras sustanciales en la modelización y en la selección de datos. Un subconjunto de objetos del marco de referencia se utilizó para referir las posiciones estelares determinadas con el satélite astrométrico Hipparcos al ICRS.

Sedimentation survey of Lago Dos Bocas, Utuado, Puerto Rico, January 2010

USGS Publications Warehouse

Soler-López, Luis R.

2014-01-01

Lago Dos Bocas reservoir was completed in 1942 to provide water for hydroelectric power generation along the northern coast of Puerto Rico. The reservoir had an original storage capacity of 37.50 million cubic meters (Mm3). The dam is located about 9 kilometers (km) northeast of the town of Utuado, immediately downstream of the original confluence of the Río Grande de Arecibo and the Río Caonillas (fig. 1). The Puerto Rico Electric Power Authority (PREPA) owns and operates the Lago Dos Bocas reservoir, and since 1996, the reservoir has become an essential part of the Puerto Rico Aqueduct and Sewer Authority (PRASA) North Coast Superaqueduct Project. The Superaqueduct is supplied by controlled releases for hydroelectric power generation that replenish the public-supply raw-water intake pool located about 10 km downstream from the Lago Dos Bocas Dam (fig. 1). As of 2005, the Superaqueduct supplies about 4.03 cubic meters per second (m3/s) (348,192 cubic meters per day [m3/d]) of potable water to communities along the northern coast, from Arecibo to the San Juan metropolitan area. Because of the importance of the reservoir to the North Coast Superaqueduct, the U.S. Geological Survey (USGS), in cooperation with PRASA, conducted a sedimentation survey of Lago Dos Bocas in January 2009. The results of this survey were used to estimate the useful life and the firm yield of the reservoir, and evaluate the need to dredge the reservoir.

Analysis of Management Practices in Lagos State Tertiary Institutions through Total Quality Management Structural Framework

ERIC Educational Resources Information Center

AbdulAzeez, Abbas Tunde

2016-01-01

This research investigated total quality management practices and quality teacher education in public tertiary institutions in Lagos State. The study was therefore designed to analyse management practices in Lagos state tertiary institutions through total quality management structural framework. The selected public tertiary institutions in Lagos…

Lagos bat virus transmission in an Eidolon helvum bat colony, Ghana.

PubMed

Freuling, Conrad M; Binger, Tabea; Beer, Martin; Adu-Sarkodie, Yaw; Schatz, Juliane; Fischer, Melina; Hanke, Dennis; Hoffmann, Bernd; Höper, Dirk; Mettenleiter, Thomas C; Oppong, Samual K; Drosten, Christian; Müller, Thomas

2015-12-02

A brain sample of a straw-coloured fruit bat (Eidolon helvum) from Ghana without evident signs of disease tested positive by generic Lyssavirus RT-PCR and direct antigen staining. Sequence analysis confirmed the presence of a Lagos bat virus belonging to phylogenetic lineage A. Virus neutralization tests using the isolate with sera from the same group of bats yielded neutralizing antibodies in 74% of 567 animals. No cross-neutralization was observed against a different Lagos bat virus (lineage B). Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluation of rare earth elements in groundwater of Lagos and Ogun States, Southwest Nigeria.

PubMed

Ayedun, H; Arowolo, T A; Gbadebo, A M; Idowu, O A

2017-06-01

Rare earth elements in our environment are becoming important because of their utilization in permanent magnets, lamp phosphors, superconductors, rechargeable batteries, catalyst, ceramics and other applications. This study was conducted to evaluate the level of rare earth elements (REE) and the variability of their anomalous behavior in groundwater samples collected from Lagos and Ogun States, Southwest, Nigeria. REE concentrations were determined in 170 groundwater samples using inductively coupled plasma-mass spectrometry, while the physicochemical parameters were determined using standard methods. Lagos State groundwater is enriched with REE [sum REEs range (mean ± SD)]; [0.365-488 (69.5 ± 117)] µg L -1 than Ogun State groundwater [sum REEs range (mean ± SD)]; [1.14-232 (22.6 ± 41.1)] µg L -1 . Boreholes are more enriched with REEs than wells. Significant (P < 0.05) positive correlation (R = Pearson) was recorded in Lagos State groundwater between sum REEs and Fe (R = 0.55). However, there were no significant correlations between sum REEs, pH (R = 0.073) and HCO 3 2- (R = 0.157) in Ogun State groundwater. Chondrite-normalized plot shows that Lagos groundwater exhibits positive Ce anomaly, while Ogun State groundwater does not. The source of REE in Lagos State may be from the ocean and leaching from wastes dumpsites, while the source in Ogun State groundwater may be from the rocks.

Climatology of equatorial stratosphere over Lagos, Nigeria

NASA Astrophysics Data System (ADS)

Oyekola, Oyedemi Samuel

We have used 12 complete calendar years (January 1993-December 2004) of monthly averages of measurements made by the Dobson spectrophotometer instrument over an urban site, Lagos (6.6oN, 3.3oE), southwest Nigeria, to study equatorial stratospheric column ozone variations and trends. Our results indicate that the time-averaged total column ozone has a seasonal cy-cle, which maximizes in June and July with a value of 259 Dobson units (DU) and minimizes in February with a magnitude of 250 DU. Statistical analysis of the climatological mean monthly total Dobson O3 record for 1993-2004 show that the local trend is approximately +0.041±0.0011 DU/year (+0.49±0.013% per decade). Spectral analysis was applied to the monthly averages series. The significant periodicity at 95% confidence level demonstrate prominent spectra peaks near 1.9 and 3.6 years, representative of quasi-biennial oscillation (QBO) and quasi-triennial oscillation (QTO), respectively. Signal due to semiannual variation is also identified at Lagos sounding site. Comparison with the ozone observations from Total Ozone Mapping Spectrom-eter (TOMS) on board the Earth-Probe (EP) satellite for the period from 1997 to 2002 reveal that EP/TOMS instrument consistently larger than the ground-based measurement from Dob-son station. Percentage mean relative disparity ranges from -11% to 15%. The root mean square error (RMSE) between satellite and ground-based observations over Lagos ranges be-tween ˜35-83 DU with largest and lowest variability occurring during the ascending phase of solar activity (1999, 10.7 cm radio flux, F10.7 equals 154 flux units) and during the peak phase of solar activity (2001, F10.7 equals 181), respectively.

Assessment of communication skills among Pharmacy students of the University of Lagos, Lagos, Nigeria

PubMed Central

Aina, BA; Ogunbiyi, OO

2011-01-01

BACKGROUND: Communication skill is the bridge between the pharmacists and the patient. Communication in health can contribute to all aspects of disease prevention and health promotion. In order to become successful pharmacists, one needs to possess excellent communication skills to serve clients. This study was conducted at the University of Lagos to assess communication skills of Pharmacy students. METHOD: The study was descriptive and cross sectional. It was carried out between May and July 2009. Questionnaires were used for data collection. The questionnaire had two sections - the bio data section and pre-formulated questions on communication skills which has three options and one of these is the best option. RESULTS: A total number of 125 respondents were involved in the study which included 25 students from 200level, 50 from 300level and 50 from 500 level. Majority of them were between 18-25 years old (89.6%). There were more females (71.2%) than males (28.8%). Also most of them were Christians (71.2%). Among the respondents, about 62% picked the best options as their answer while the rest picked other options. There was no statistical difference in the choice of best options between the different levels of study. CONCLUSIONS: It can be concluded from the results of this study that majority of Pharmacy Students at the University of Lagos had good communication skills and they will be able to discharge their duties as pharmacists when they eventually graduate. PMID:24826026

Influence of Counselling Services on Perceived Academic Performance of Secondary School Students in Lagos State

ERIC Educational Resources Information Center

Bolu-Steve, Foluke; Oredugba, Oluwabunmi Olayinka

2017-01-01

This study aimed at looking at the influence of counseling services on perceived academic performance of secondary school students in Lagos State. At the first stage, the researchers purposively selected Ikorodu L.G.A in Lagos State. At the researchers selected two schools (1 Private schools, & 1 Public schools), using simple random technique.…

The Geologic and Geochemical Setting of Lago Fagnano, Tierra del Fuego, Argentina

NASA Astrophysics Data System (ADS)

Tingle, D.; Odle, K.; Knettel, P.; Redding, S.; Perry, E.; Ellins, K.; Ormiston, C.; Dovzak, N.; Anderson, S.

2005-12-01

Lago Fagnano, Tierra del Fuego, Argentina is the largest and southernmost ice-free lake on Earth. The isolated lake is unique because the geographic and geologic context provides information relating to the westerly wind patterns, interaction of multiple water sources (hot springs, glacial meltwater, precipitation, groundwater), and tectonic dynamics along a major transform fault. In March, 2005, four students and three teachers from Boerne High School, south-central Texas joined scientists from the United States, Argentina and Switzerland engaged in a geophysical survey of this lake. Lago Fagnano potentially contains within its sediments an undisturbed record of the geotectonic and global climate variability of past 20,000 years. The science team imaged the lake floor with a boat specially equipped to collect both high resolution data (high frequency), imaging the upper 10-15 meters of the sediment, and long range data (low frequency), penetrating 100 or more meters into the sediment. The group conducted field research of existing tectonic features at the eastern end of Tierra del Fuego, an activity directly tied to the research objectives of the science team. They also collected water and soil samples to assess chemical and isotopic trends in the Lago Fagnano region. The research performed can help to characterize the modern geochemical setting of the lake. Analyses of dissolved oxygen, NH4+, PO42-, pH (water) and N, P, and pH (soils) demonstrate a link between low nutrient levels and low biodiversity (which was confirmed by observation) in Tierra del Fuego. Water and soil data are incorporated into a database to facilitate comparisons to North American samples collected and analyzed during the Boerne High School summer field courses. Twenty-three ^18O and ^D analyses yielded a south-north isotopic trend across the Lago Fagnano region. ^18O and ^D transition from -11.92 to -3.53% and -87.81 to -40.26%, respectively, moving south to the Beagle Channel. These

Within salvation: girl hawkers and the colonial state in development era Lagos.

PubMed

George, Abosede

2011-01-01

For almost two decades between the close of the Second World War and Nigerian independence in 1960, the British colonial state which faced a crisis of legitimacy in Lagos upheld city ordinances that made itinerant trading by young children in Lagos a punishable status offense. Although anti-trading regulations were gender-neutral in their language, girls were disproportionately sanctioned for engaging in street trading and related activities. In defending their concentration on girl sellers over boy sellers, colonial welfare officials painted a picture of the urban context as an inherently dangerous context and of girls as being particularly at risk of violent assault in the city, making them particularly in need of protection from town life. Sources which show that parents generally resisted or ignored the street trading regulations and continued permitting their daughters to sell despite entreaties, warnings, or fines from colonial officials, suggest that African parents and British colonial officials may have had conflicting views on the inherent danger of the city, on what constituted child endangerment, and on the gendered nature of childhood. This article argues that the girl saving campaigns of development era Lagos were as much about the legitimization of a colonial state facing a crisis of legitimacy as they were about debates between African parents and colonial welfare officials in Lagos concerning ideas of children and childhood and the dangers of street trading by African girls.

Using satellite images to monitor glacial-lake outburst floods: Lago Cachet Dos drainage, Chile

USGS Publications Warehouse

Friesen, Beverly A.; Cole, Christopher J.; Nimick, David A.; Wilson, Earl M.; Fahey, Mark J.; McGrath, Daniel J.; Leidich, Jonathan

2015-01-01

During 2008–2013, 14 GLOFs were released from Lago Cachet Dos and created environmental and safety concerns for downstream residents and to infrastructure. If GLOFs and the consequent headward erosion continue, the moraine that creates Lago Cachet Uno could be destabilized and breached, and the two lakes could merge. If the two lakes become connected, the volume of future GLOFs likely would be greater and thus cause longer and (or) more extensive flooding downstream. Additional GLOFs from Lago Cachet Dos are expected in the future, and continued environmental monitoring could provide an early warning system as well as scientific information that could increase our understanding of GLOFs and their consequences. GLOFs occur in glaciated areas around the world and remote sensing technologies can allow researchers to better understand—and potentially predict—future GLOF events.

Calibration of a large water-Cherenkov detector at the Sierra Negra site of LAGO

NASA Astrophysics Data System (ADS)

Galindo, A.; Moreno, E.; Carrasco, E.; Torres, I.; Carramiñana, A.; Bonilla, M.; Salazar, H.; Conde, R.; Alvarez, W.; Alvarez, C.; Araujo, C.; Areso, O.; Arnaldi, H.; Asorey, H.; Audelo, M.; Barros, H.; Bonnett, M.; Calderon, R.; Calderon, M.; Campos-Fauth, A.; Carramiñana, A.; Carrasco, E.; Carrera, E.; Cazar, D.; Cifuentes, E.; Collogo, D.; Conde, R.; Cotzomi, J.; Dasso, S.; De Castro, A.; De La Torre, J.; De León, R.; Estupiñan, A.; Galindo, A.; García, L.; Gomez Berisso, M.; González, M.; Guevara, W.; Gulisano, A. M.; Hernández, H.; Jaimes, A.; López, J.; Mantilla, C.; Martín, R.; Martinez-Mendez, A.; Martínez, O.; Martins, E.; Macías-Meza, J. J.; Mayo-García, R.; Melo, T.; Mendoza, J.; Miranda, P.; Montes, E.; Morales, E.; Morales, I.; Moreno, E.; Murrugarra, C.; Nina, C.; Núñez, L. A.; Núñez-Castiñeyra, A.; Otiniano, L.; Peña-Rodríguez, J.; Perenguez, J.; Pérez, H.; Pérez, Y.; Pérez, G.; Pinilla-Velandia, S.; Ponce, E.; Quishpe, R.; Quispe, F.; Ramelli, M.; Reyes, K.; Rivera, H.; Rodriguez, J.; Rodríguez-Ferreira, J.; Rodríguez-Pascual, M.; Romero, M.; Rubio-Montero, A. J.; Salazar, H.; Salinas, J.; Sarmiento-Cano, C.; Sidelnik, I.; Sofo Haro, M.; Suárez-Durán, M.; Subieta, M.; Tello, J.; Ticona, R.; Torres, I.; Torres-Niõ, L.; Truyenque, J.; Valencia-Otero, M.; Vargas, S.; Vásquez, N.; Villaseñor, L.; Zamalloa, M.; Zavala, L.; LAGO Collaboration

2017-07-01

The Latin American Giant Observatory (LAGO) is an international network of water-Cherenkov detectors (WCD) set in different sites across Latin America. On top of the Sierra Negra volcano in Mexico at an altitude of 4530 m, LAGO has completed its first out of three instrumented detector. It consists of a cylindrical water tank with a diameter of 7.3 m and a height of 1 m and a total detection area of 40 m2 that is sectioned in four equal slices. In this work we present the full calibration procedure of this detector and the initial measurements of stability in rate. We also derive the effective area to gamma-ray bursts for the complete array using the LAGO simulation chain, based on CORSIKA and GEANT4.

The data acquisition system of the Latin American Giant Observatory (LAGO)

NASA Astrophysics Data System (ADS)

Sofo Haro, M.; Arnaldi, L. H.; Alvarez, W.; Alvarez, C.; Araujo, C.; Areso, O.; Arnaldi, H.; Asorey, H.; Audelo, M.; Barros, H.; Bertou, X.; Bonnett, M.; Calderon, R.; Calderon, M.; Campos-Fauth, A.; Carramiñana, A.; Carrasco, E.; Carrera, E.; Cazar, D.; Cifuentes, E.; Cogollo, D.; Conde, R.; Cotzomi, J.; Dasso, S.; De Castro, A.; De La Torre, J.; De León, R.; Estupiñan, A.; Galindo, A.; Garcia, L.; Gómez Berisso, M.; González, M.; Guevara, W.; Gulisano, A. M.; Hernández, H.; Jaimes, A.; López, J.; Mantilla, C.; Martín, R.; Martinez-Mendez, A.; Martínez, O.; Martins, E.; Masías-Meza, J. J.; Mayo-García, R.; Melo, T.; Mendoza, J.; Miranda, P.; Montes, E.; Morales, E.; Morales, I.; Moreno, E.; Murrugarra, C.; Nina, C.; Núñez, L. A.; Núñez-Castiñeyra, A.; Otiniano, L.; Peña-Rodríguez, J.; Perenguez, J.; Pérez, H.; Perez, Y.; Perez, G.; Pinilla-Velandia, S.; Ponce, E.; Quishpe, R.; Quispe, F.; Reyes, K.; Rivera, H.; Rodriguez, J.; Rodríguez-Pascual, M.; Romero, M.; Rubio-Montero, A. J.; Salazar, H.; Salinas, J.; Sarmiento-Cano, C.; Sidelnik, I.; Haro, M. Sofo; Suárez-Durán, M.; Subieta, M.; Tello, J.; Ticona, R.; Torres, I.; Torres-Niño, L.; Truyenque, J.; Valencia-Otero, M.; Vargas, S.; Vásquez, N.; Villasenor, L.; Zamalloa, M.; Zavala, L.

2016-06-01

LAGO is an extended cosmic ray observatory composed of water-Cherenkov detectors (WCD) placed throughout Latin America. It is dedicated to the study of various issues related to astrophysics, space weather and atmospheric physics at the regional scale. In this paper we present the design and implementation of the front-end electronics and the data acquisition system for readout of the WCDs of LAGO. The system consists of preamplifiers and a digital board sending data to a computer via an USB interface. The analog signals are acquired from three independent channels at a maximum rate of ~1.2×105 pulses per second and a sampling rate of 40 MHz. To avoid false trigger due to baseline fluctuations, we present in this work a baseline correction algorithm that makes it possible to use WCDs to study variations of the environmental radiation. A data logging software has been designed to format the received data. It also enables an easy access to the data for an off-line analysis, together with the operational conditions and environmental information. The system is currently used at different sites of LAGO.

Assessing the deep drilling potential of Lago de Tota, Colombia, with a seismic survey

NASA Astrophysics Data System (ADS)

Bird, B. W.; Wattrus, N. J.; Fonseca, H.; Velasco, F.; Escobar, J.

2015-12-01

Reconciling orbital-scale patterns of inter-hemispheric South American climate during the Quaternary requires continuous, high-resolution paleoclimate records that span multiple glacial cycles from both hemispheres. Southern Andean Quaternary climates are represented by multi-proxy results from Lake Titicaca (Peru-Bolivia) spanning the last 400 ka and by pending results from the Lago Junin Drilling Project (Peru). Although Northern Andean sediment records spanning the last few million years have been retrieved from the Bogota and Fúquene Basins in the Eastern Cordillera of the Colombian Andes, climatic reconstructions based on these cores have thus far been limited to pollen-based investigations. When viewed together with the Southern Hemisphere results, these records suggest an anti-phased hemispheric climatic response during glacial cycles. In order to better assess orbital-scale climate responses, however, independent temperature and hydroclimate proxies from the Northern Hemisphere are needed in addition to vegetation histories. As part of this objective, an effort is underway to develop a paleoclimate record from Lago de Tota (3030 m asl), the largest lake in Colombia and the third largest lake in the Andes. One of 17 highland tectonic basins in Eastern Cordillera, Lago de Tota formed during Tertiary uplift that deformed pre-foreland megasequences, synrift and back-arc megasequences. The precise age and thickness of sediments in the Lago de Tota basin has not previously been established. Here, we present results from a recent single-channel seismic reflection survey collected with a small (5 cubic inch) air gun and high-resolution CHIRP sub-bottom data. With these data, we examine the depositional history and sequence stratigraphy of Lago de Tota and assess its potential as a deep drilling target.

Sedimentation survey of Lago Lucchetti, Yauco, Puerto Rico, September 2013–May 2014

USGS Publications Warehouse

Gómez-Fragoso, Julieta

2016-08-23

The U.S. Geological Survey conducted a sedimentation survey of Lago Lucchetti, Yauco, Puerto Rico, in 2013–14 in cooperation with the Puerto Rico Aqueduct and Sewer Authority. The survey updated a previous survey, conducted in 2000, and provided accurate information regarding reservoir storage capacity and sedimen­tation rate using bathymetric techniques and a global positioning system coupled with a depth sounder device. The results of the 2013–14 survey indicated a total storage capacity for Lago Lucchetti of 10.21 million cubic meters and a long­-term sedimentation rate loss of 0.16 million cubic meters per year based on the original capacity in 1952. Sediment accumulation was about 10.14 million cubic meters over the life of the reservoir, which represents a storage decrease of about 50 percent of the original capacity in 1952. On the basis of a comparison between the 2013–14 and 2000 surveys, the useful life for Lago Lucchetti is projected to end in 2076.

Nuevos sistemas de frecuencia intermedia para el IAR

NASA Astrophysics Data System (ADS)

Olalde, J. C.; Perilli, D.; Larrarte, J. J.

Se presenta el diagrama en bloques de los nuevos sistemas de Frecuencia Intermedia para los dos radiómetros instalados en el IAR. Entre las características más importantes del sistema podemos mencionar la posibilidad de conectar cualquiera de las dos antenas a los ``backend" disponibles: analizador espectral de alta resolución (META II) de 0,05 Hz, autocorrelador de 1008 canales y contínuo. Se incorporan al sistema nuevos sintetizadores de frecuencia implementados con PLL y la moderna técnica de síntesis digital directa. Por último, el conjunto del sistema es susceptible de ser configurado por las computadoras de adquisición de datos, supervisadas por otra, que entrega el estado de funcionamiento actual y evita la selección de configuraciones incorrectas por parte del usuario.

Data of the properties of rebar steel brands in Lagos, Nigerian market used in reinforced concrete applications.

PubMed

Joshua, Opeyemi; Olusola, Kolapo O; Oyeyemi, Kehinde D; Ogunde, Ayodeji O; Amusan, Lekan M; Nduka, David O; Abuka-Joshua, Joyce

2018-04-01

The data presented herein are compilations of the research summary of "Assessment of the Quality of Steel Reinforcement Bars Available in Nigerian Market" (Joshua et al., 2013) [1]. This data article provides information on the properties and cost of steel rebars used in reinforced concrete in Lagos, Nigeria. The data is based on the properties of 12 mm rebar brands which are the most used steel diameter in construction and they include actual diameters, yield strengths, ultimate strengths, ultimate/yield strength ratio, ductility and the cost of each brand. This data also contains the limiting standard properties of the highlighted properties in this data.

Storage capacity and sedimentation trends of Lago Garzas, Puerto Rico, 1996-2007

USGS Publications Warehouse

Soler-Lopez, L.R.

2012-01-01

Lago Garzas is located in west-central Puerto Rico, about 3.5 kilometers southwest of the town of Adjuntas, in the confluence of the Río Vacas and three other unnamed tributaries (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA), and was constructed in 1943 for hydroelectric power generation and municipal water use along the southern coast. The dam is a semi-hydraulic earthfill embankment lined with boulders, and has a height of 61.57 meters, a top width of 9.14 meters, a base width of 365.76 meters, and a crest length of 227.37 meters; State Road PR-518 crosses the top of the dam. A morning-glory-type spillway is located near the west abutment of the dam at an elevation of 736.12 meters above mean sea level (Puerto Rico Water Resources Authority, 1969). Figure 2 shows an aerial photograph of the Lago Garzas earthfill dam and the morning-glory spillway section. Additional information and operational procedures are provided in Soler-López and others (1999). During July 17-18, 2007, the U.S. Geological Survey (USGS) Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, conducted a bathymetric survey of Lago Garzas to update the reservoir storage capacity and update the reservoir sedimentation rate by comparing the 2007 data with the previous 1996 bathymetric survey results. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago Garzas during July 2007, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1996.

Drivers and Pattern of Social Vulnerability to Flood in Metropolitan Lagos, Nigeria

NASA Astrophysics Data System (ADS)

Fasona, M.

2016-12-01

Lagos is Africa's second largest city and a city-state in southwest Nigeria. Population and economic activities in the city are concentrated in the greater Lagos metropolitan area - a group of barrier islands less than a thousand square kilometer. Several physical factors and critical human-environmental conditions contribute to high flood vulnerability across the city. Flood impact is highly denominated and the poor tend to suffer more due to higher risk of exposure and poor adaptive capacity. In this study we present the pattern of social vulnerability to flooding across the Lagos metropolis and argued that the pattern substantially reflects the pattern and severity of flooding impact on people across the metropolis. Twenty nine social indicators and experiences including poverty profile, housing conditions, education, population and demography, social network, and communication, among others, were considered. The data were collated through field survey and subjected to principal component analysis. The results were processed into raster surfaces using GIS for social vulnerability characterization at neighborhood levels. The results suggest the social status indicators, neighborhood standing and social networks indictors, the indicators of emergency responses and security, and the neighborhood conditions, in that order, are the most important determinants of social vulnerability. Six of the 16 LGAs in metropolitan Lagos have high social vulnerability. Neighborhoods that combine poor social status indicators and poor neighborhood standing and social networks are found to have high social vulnerability whereas other poor neighborhoods with strong social networks performed better. We conclude that improved human living condition and social network and communication in poor urban neighborhoods are important to reducing social vulnerability to flooding in the metropolis.

Hourly global and diffuse radiation of Lagos, Nigeria-correlation with some atmospheric parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chendo, M.A.C.; Maduekwe, A.A.L.

1994-03-01

The influence of four climatic parameters on the hourly diffuse fraction in Lagos, Nigeria, has been studied. Using data for two years, new correlations were established. The standard error of the Liu and Jordan-type equation was reduced by 12.83% when solar elevation, ambient temperature, and relative humidity were used together as predictor variables for the entire data set. Ambient temperature and relative humidity proved to be very important variables for predicting the diffuse fraction of the solar radiation passing through the humid atmosphere of the coastal and tropic city of Lagos. Seasonal analysis carried out with the data showed improvementsmore » on the standard errors for the new seasonal correlations. In the case of the dry season, the improvement was 18.37%, whole for the wet season, this was 12.37%. Comparison with existing correlations showed that the performance of the one parameter model (namely K[sub t]), of Orgill and Hollands and Reindl, Beckman, and Duffie were very different from the Liu and Jordan-type model obtained for Lagos.« less

Nutritional status of urban and rural primary school pupils in Lagos State, Nigeria.

PubMed

Ekekezie, O O; Odeyemi, K A; Ibeabuchi, N M

2012-01-01

This study was carried out in Lagos State in Ikorodu LGA (rural), a largely agrarian area producing raw materials for agro-allied industries and Ikeja LGA (urban), a highly-developed metropolis and commercial centre. Hitherto, studies showed that undernutrition had been the main form of malnutrition among Nigerian children. However with influences from urbanization, westernization and globalization in cosmopolitan Lagos, it is imperative to find out if the global epidemic of overweight and obesity has caught on. To compare the nutritional status of primary school pupils in urban and rural LGAs in Lagos State, Nigeria. This was a cross , sectional comparative study. A multistage sampling method was adopted. Data were collected from 529 pupils with an interviewer administered questionnaire. Their weight and height were recorded in pre-designed proforma and converted to nutritional indices. The prevalence rates of underweight, stunting and wasting in the rural area were 49.6%, 50.8% and 24.2% respectively; while it was 15.1%, 16.6% and 13.6% in the urban area respectively. There was overnutrition in the urban area: 15.1% were overweight and 13.2% were obese. The mean nutritional indices were significantly lower among the rural pupils than urban pupils (p<0.001) in each case. Undernutrition is still a major health problem among school children in Lagos State, Nigeria, more so in the rural area. There is an emergence of overweight and obesity in the urban area. A comprehensive programme to improve nutritional status is recommended as part of a well funded school health programme.

The glacial geomorphology of the Lago Buenos Aires and Lago Puerreydón ice lobes, Central Patagonia

NASA Astrophysics Data System (ADS)

Bendle, Jacob; Thorndycraft, Varyl; Palmer, Adrian

2016-04-01

Patagonia is ideally located for reconstructions of late Quaternary ice-climate interaction(s) in the Southern Hemisphere mid-latitudes, yet many questions remain concerning post-LGM ice sheet retreat dynamics across the region. While modern-day glaciation is restricted to three small icefields (the North and South Patagonian and Cordillera Darwin icefields), during the Quaternary, and at the LGM, episodes of significant ice advance culminated in an expansive Patagonian ice sheet (PIS) centered over the southern Andes, for which a long and well-preserved landform record exists. Previous mapping in the region has either aimed to achieve regional coverage, necessarily omitting more subtle/complex features suggestive of certain ice-marginal processes, or has focused on the identification of palaeo-ice limits (e.g. moraine ridges) for geochronological applications, with little attention given to other (e.g. glaciofluvial, glaciolacustrine) features that are significant for understanding post-LGM ice sheet retreat dynamics. This poster presents a comprehensive and highly detailed (<30m spatial resolution) map of the glacial geomorphology of the Lago Buenos Aires (46.4°S) and Lago Puerreydón (47.2°S) ice lobes, major outlet glaciers of the central sector of the former PIS. The map allows refined reconstructions of glacial and, in particular, deglacial ice-marginal processes, and will underpin further analysis on the retreat history of the palaeo-ice lobes using high-resolution lithostratigraphic (varve) analyses.

Sedimentation Survey of Lago La Plata, Puerto Rico, July 2006

USGS Publications Warehouse

Soler-López, Luis R.

2008-01-01

Lago La Plata dam is located between the municipalities of Naranjito and Toa Alta in north central Puerto Rico, about 5 kilometers south of the town of Toa Alta and about 5 kilometers north of the town of Naranjito. The reservoir impounds the waters of the Rio de La Plata, the Rio Guadiana, and the Rio Ca?as, and is part of the San Juan Metropolitan Water District, which provides about 35 percent of the total water demand for the area (Soler-Lopez and others, 2000). The reservoir has a drainage area of about 469 square kilometers. The dam was constructed in 1974 and is a concrete gravity structure with a normal pool elevation of 52.00 meters above mean sea level (Puerto Rico Electric Power Authority, 1979). During October 1998, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago La Plata to assess the impact of Hurricane Georges on the storage capacity of the reservoir. Between July 17 and 20, 2006, the USGS and the PRASA conducted an additional bathymetric survey of Lago La Plata to update the reservoir storage capacity and determine the reservoir sedimentation rate by comparing the 2006 survey data with the 1998 survey data.. The purpose of this report is to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1998. Historical (1974) data are referenced as needed to account for long-term storage capacity loss trends...

Sedimentation Survey of Lago de Cidra, Puerto Rico, August 2007

USGS Publications Warehouse

Soler-López, Luis R.

2010-01-01

Lago de Cidra is a reservoir located on the confluence of Rio de Bayamon, Rio Sabana, and Quebrada Prieta, in the municipality of Cidra in east-central Puerto Rico, about 3.0 kilometers northeast of the town of Cidra. The dam is owned and operated by the Puerto Rico Aqueduct and Sewer Authority (PRASA), and was constructed in 1946 as a 6.54-million-cubic-meter supplemental water supply for the San Juan metropolitan area. The reservoir impounds the waters of Rio de Bayamon, Rio Sabana and Quebrada Prieta. The reservoir has a drainage area of 21.4 square kilometers. The dam is a concrete gravity and earthfill structure with a length of approximately 165 meters and a structural height of 24 meters. The spillway portion of the dam is an ungated ogee crest about 40 meters long with a crest elevation of 403.00 meters above mean sea level. Additional information and operational procedures are listed in Soler-Lopez (1999). During August 14-15, 2007, the U.S. Geological Survey (USGS), Caribbean Water Science Center (CWSC), in cooperation with the PRASA, conducted a bathymetric survey of Lago de Cidra to update the reservoir storage capacity and actualize the reservoir sedimentation rate by comparing the 2007 data with the previous 1997 bathymetric survey data. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago de Cidra during August 2007, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1997.

Healthcare waste management status in Lagos State, Nigeria: a case study from selected healthcare facilities in Ikorodu and Lagos metropolis.

PubMed

Longe, Ezechiel O

2012-06-01

A survey of healthcare waste management practices and their implications for health and the environment was carried out. The study assessed waste management practices in 20 healthcare facilities ranging in capacity from 40 to 600 beds in Ikorodu and metropolitan Lagos, Lagos State, Nigeria. The prevailing healthcare waste management status was analysed. Management issues on quantities and proportion of different constituents of waste, segregation, collection, handling, transportation, treatment and disposal methods were assessed. The waste generation averaged 0.631 kg bed(-1) day(-1) over the survey area. The waste stream from the healthcare facilities consisted of general waste (59.0%), infectious waste (29.7%), sharps and pathological (8.9%), chemical (1.45%) and others (0.95%). Sharps/pathological waste includes disposable syringes. In general, the waste materials were collected in a mixed form, transported and disposed of along with municipal solid waste with attendant risks to health and safety. Most facilities lacked appropriate treatment systems for a variety of reasons that included inadequate funding and little or no priority for healthcare waste management as well as a lack of professionally competent waste managers among healthcare providers. Hazards associated with healthcare waste management and shortcomings in the existing system were identified.

Lagos "Area Boys", Substance Usage and Potential Risk Factors

ERIC Educational Resources Information Center

Salaam, Abeeb Olufemi; Brown, Jennifer

2012-01-01

The current study explores the rate at which members of Lagos' "area boys" engage in drug and alcohol use, and determines the predictive roles of parental and neighbourhood characteristics in the gang patterns of psychoactive substance misuse behaviour. The study approached gang members (N = 129) aged from 18 to 38 years (M = 25.83, SD = 4.82)…

Comparison of Storage Capacity and Sedimentation Trends of Lago Guayabal, Puerto Rico-December 2001 and October 2006

USGS Publications Warehouse

Soler-López, Luis R.

2008-01-01

Lago Guayabal dam is located on the Rio Jacaguas in the municipality of Villalba in southern Puerto Rico, about 4 kilometers north of the town of Juana Diaz and about 5 kilometers south of Villalba (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA) and was constructed in 1913 for the irrigation of croplands in the southern coastal plains of Puerto Rico. The reservoir impounds the waters of the Rio Jacaguas and those of the Rio Toa Vaca, when the Toa Vaca dam overflows or releases water. The reservoir has a drainage area of 53.8 square kilometers. The dam is a concrete gravity structure with a normal pool (at top of flashboards) elevation of 103.94 meters above mean sea level (Puerto Rico Electric Power Authority, 1988). During October 2006, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago Guayabal to update the reservoir storage capacity and actualize the reservoir sedimentation rate by comparing the 2006 data with the previous 2001 bathymetric survey results. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago Guayabal during October 2006, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since December 2001. The Lago Guayabal sedimentation history up to 2001 was published by the USGS in 2003 (Soler-Lopez, 2003); therefore, this report focuses on the comparison between the 2001 and current bathymetric surveys of Lago Guayabal.

Arterial injuries in civilian practice in Lagos, Nigeria.

PubMed

Thomas, M O; Giwa, S O; Adekoya-Cole, T O

2005-12-01

This is a retrospective study of patients managed at the Lagos University Teaching Hospital for peripheral arterial injuries from January 1995 to April 2003. The aim was to study the pattern of peripheral arterial injuries in Lagos. Nigeria and to look at the outcome of management and see what improvements could be made in future. Data was collated from case notes of patients, operation register in theatre and admission and discharge books from the surgical wards and the data bank of consultants involved in patients' management. Forty-one patients. 37 males and 4 females. were treated within the study period (M:F ratio of 9:1). Twenty three patients (56.1%) suffered gunshot injuries during armed robbery attacks while 9 patients (22.0%) had stab injuries in civilian violence. Twenty-one patients (3 with gunshot injuries and 18 non gunshot penetrating injuries) were managed by direct suturing of vessels. Eight patients had prosthetic graft interposition while 2 patients had reversed saphenous vein grafts. Two patients had the superficial branches of their radial arteries tied up at the wrist. Gun shot injuries from armed robbery attack was the commonest cause of peripheral arterial injuries in this environment during the period of study.

Electricity supply efficiency and organizational growth and profitability in Lagos, Nigeria

NASA Astrophysics Data System (ADS)

Adeleke, Adedeji Tajudeen

A modern and efficient infrastructure is a basic necessity for economic development and integration into the global economy. The specific problem was the inadequate and unreliable supply of electricity to manufacturing corporations in Lagos, Nigeria. The purpose of the current quantitative correlational research study was to examine if there was a correlation between electricity supply efficiency and organizational growth and profitability in manufacturing corporations in Lagos, Nigeria. The population of the current correlational research study involved 28 out of 34 manufacturing corporations from various industrial sectors in Lagos, Nigeria, that are listed and traded on the Nigerian Stock Exchange. Spearman rho correlations were used to assess the relationships between independent variables of electricity supply efficiency levels and the dependent variables of organizational growth and profitability. The result of the correlational analysis of the data revealed that there was a statistically significant, strong positive correlation between the Average Gross Income (1998-2007) and Average Actual Electricity supply efficiency level (1998-2007), rho = 0.57; p = 0.002. A statistically significant, strong positive correlation was found between the Average Balance Sheet Size (1998-2007) and Average Actual Electricity Supply Efficiency Level (1998-2007), rho = 0.54; p = 0.003. A statistically significant, strong positive correlation between the Average Profit After Tax (1998-2007) and Average Actual Electricity Supply Efficiency Level (1998-2007), rho = 0.60; p = 0.001, was found. No statistically significant correlation between the Average Return on Investment (1998-2007) and Average Actual Electricity supply efficiency level (1998-2007), rho = 0.19; p = 0.33, was discovered.

Motivations for Gang Membership in Lagos, Nigeria: Challenge and Resilience

ERIC Educational Resources Information Center

Salaam, Abeeb Olufemi

2011-01-01

The current study explores the major challenges (in the form of risk factors) that may influence unemployed youths' involvement in gang and criminal activity in Lagos, Nigeria. A combination of techniques (e.g., oral, in-depth interviews, and questionnaires) were used for the data collection. The computed outcomes establish some of the major…

An Analysis of Deaths Due to Tuberculosis at the Lagos University Teaching Hospital

PubMed Central

Bandele, E.O.; Olude, I.O.

1985-01-01

An analysis was made of deaths from tuberculosis in the Lagos University Teaching Hospital from 1976 to 1980. Of the 320 patients assessed, 240 were determined to have died from tuberculosis. Tuberculous meningitis was the main cause of death. Forty-two percent of the deaths occurred in the age group of 0 to 10 years old, and 47.5 percent of the patients died within one week of diagnosis. Potentially avoidable factors contributing to death include late reporting by patients to medical personnel, lack of bacillus of Calmette and Guerin (BCG) vaccine, irregular taking of medications by patients, and late referral of patients to specialized hospitals. There is a need for improved education of patients and medical personnel about the management of tuberculosis in Lagos. PMID:4046063

Dog Ecology and Population Studies in Lagos State, Nigeria

PubMed Central

Hambolu, Sunday E.; Dzikwi, Asabe A.; Kwaga, Jacob K.P.; Kazeem, Haruna M.; Umoh, Jarlath U.; Hambolu, Dupe A.

2014-01-01

Dog population dynamics have a major impact upon the effectiveness of rabies control strategies. As such, understanding domestic dog ecology has been recognized as central to the design of effective rabies control programmes. This study was conducted to determine the dog ecology in Lagos State using compound dog count and street dog count in the three senatorial districts (Lagos West, East and Central) of Lagos State from February, 2011 to January, 2012. A total of 546 questionnaires were distributed for the compound dog count and all were completed and returned. Various aspects of dog ecology were determined, including size, sex, breed of the dog population, management of dogs and rabies awareness among the respondents. Out of the 546 compounds surveyed, 518 (94.87%) owned at least one dog. A total of 1,427 dogs were counted from the street counts while a total of 1,447 dogs (2.8 dogs/compound) were counted from the compound count. The dogs comprised of 583 males and 864 females, out of which 64.10% are confined. The dog vaccination coverage in the dog population surveyed was 64.10% and administered majorly (91.30%) by veterinarians. Security (60%) and pets (26%) were the major reasons for keeping dogs. Majority (88.80%) of the respondents were aware of rabies and its mode of transmission, but still believed in the use of concoctions (40.40%), herbs (19.90%) and consumption of the organ of the offending dog (11.50%) for the treatment of rabies. The findings of this study showed a male: female ratio of dog to be 1:1.5 and a dog: human ratio of 1:5.6. There was also a responsible dog ownership as majority of the respondents do confine, vaccinate and provide food for their dogs. Vaccination coverage of the total dog population was however below the 70-80% target recommended by the World Health Organization to achieve herd immunity. PMID:24576383

Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

NASA Astrophysics Data System (ADS)

Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

2016-12-01

Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P < 0.05) across the wetland areas. Also, dissolved inorganic carbon (DIC) contributed to most of the total dissolved solids (TDS) since only DIC correlated significantly with TDS (r = 0.889; P = 0.05, n = 12) and TS (r = 0.891; P = 0.05, n = 12), suggesting a strong capacity for carbon sequestration and carbon sink across the wetland areas. None of the encountered vegetation species are in the vulnerable category of the International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local

Decision scenario analysis for addressing sediment accumulation in Lago Lucchetti, Puerto Rico

EPA Science Inventory

A Bayesian belief network (BBN) was used to characterize the effects of sediment accumulation on water storage capacity of a reservoir (Lago Lucchetti) in southwest Puerto Rico and the potential of different management options to increase reservoir life expectancy. Water and sedi...

Recovery and recycling practices in municipal solid waste management in Lagos, Nigeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kofoworola, O.F.

The population of Lagos, the largest city in Nigeria, increased seven times from 1950 to 1980 with a current population of over 10 million inhabitants. The majority of the city's residents are poor. The residents make a heavy demand on resources and, at the same time, generate large quantities of solid waste. Approximately 4 million tonnes of municipal solid waste (MSW) is generated annually in the city, including approximately 0.5 million of untreated industrial waste. This is approximately 1.1 kg/cap/day. Efforts by the various waste management agencies set up by the state government to keep its streets and neighborhoods cleanmore » have achieved only minimal success. This is because more than half of these wastes are left uncollected from the streets and the various locations due to the inadequacy and inefficiency of the waste management system. Whilst the benefits of proper solid waste management (SWM), such as increased revenues for municipal bodies, higher productivity rate, improved sanitation standards and better health conditions, cannot be overemphasized, it is important that there is a reduction in the quantity of recoverable materials in residential and commercial waste streams to minimize the problem of MSW disposal. This paper examines the status of recovery and recycling in current waste management practice in Lagos, Nigeria. Existing recovery and recycling patterns, recovery and recycling technologies, approaches to materials recycling, and the types of materials recovered from MSW are reviewed. Based on these, strategies for improving recovery and recycling practices in the management of MSW in Lagos, Nigeria are suggested.« less

Pattern and outcome of cases seen at the Adult Accident and Emergency Department of the Lagos University Teaching Hospital, Idi-Araba, Lagos.

PubMed

Uzoechina, N S; Abiola, A O; Akodu, B A; Mbakwem, A; Arogundade, A R; Tijani, H; Adegbesan-Omilabu, M A

2012-01-01

The accident and emergency department constitutes one of the vital entry points of patients into the healthcare facility of the hospital the world over. It responds to and manages variety of cases in all the clinical areas and thus pr vides an insight to the quality of care available in the health institution. The aim of this study is to determine the pattern of cases seen as well as the causes of deaths at the adult accident and emergency department of the Lagos UniversityTeaching Hospital, Idi-Araba, Lagos. Retrospective review of records of all patients attended to at the adult accident and emergency department of the Lagos University Teaching Hospital in 2009 and 2010 was carried out. Data spread sheet was used to collect data on demographic indices, diagnosis, outcome, date admitted, date discharged and amount paid from casualty attendance register and Nurses' report books. Data was collated and analysed using Epi-Info version 3.4.1 statistical software package. Out of the 5,427 available patients' records reviewed, 4,761(87.7%) were recorded as "discharged alive", 546 (10.1%) were recorded as "died", while 120 (2.2%) were recorded as "brought in dead". Of those discharged alive, male attendance was 2,376 (49.10%) while that of the female was 2,385 (50.10%). Majority of these patients were aged 20-39 years and the mean age of the patients was 39.96 +/- 18.22 yrs. Majority of cases seen were medical in origin (53.7%) and highest medical case seen was cerebrovascular accident, Commonest cause of death was from medical cases [69.2%] (cerebrovascular accident 22.0%). Male mortality was 55.3% while female mortality was 44.7%, mean age was 46.86 +/- 17.61. Most affected age group was 40 - 59 years (35.4%) and highest number of death was seen in December. The commonest case seen as well as commonest cause of death was cerebrovascular accident. A high number of heart failure, head injuries, road traffic accidents, upper gastrointestinal bleeding and post partum

Profile of medical waste management in two healthcare facilities in Lagos, Nigeria: a case study.

PubMed

Idowu, Ibijoke; Alo, Babajide; Atherton, William; Al Khaddar, Rafid

2013-05-01

Proper management and safe disposal of medical waste (MW) is vital in the reduction of infection or illness through contact with discarded material and in the prevention of environmental contamination in hospital facilities. The management practices for MW in selected healthcare facilities in Lagos, Nigeria were assessed. The cross-sectional study involved the use of questionnaires, in-depth interviews, focused group discussions and participant observation strategies. It also involved the collection, segregation, identification and weighing of waste types from wards and units in the representative facilities in Lagos, Nigeria, for qualitative and quantitative analysis of the MW streams. The findings indicated that the selected Nigerian healthcare facilities were lacking in the adoption of sound MW management (MWM) practices. The average MW ranged from 0.01 kg/bed/day to 3.98 kg/bed/day. Moreover, about 30% of the domestic waste from the healthcare facilities consisted of MW due to inappropriate co-disposal practices. Multiple linear regression was applied to predict the volume of waste generated giving a correlation coefficient (R(2)) value of 0.99 confirming a good fit of the data. This study revealed that the current MWM practices and strategies in Lagos are weak, and suggests an urgent need for review to achieve vital reversals in the current trends.

Anti-malarial drug quality in Lagos and Accra - a comparison of various quality assessments

PubMed Central

2010-01-01

Background Two major cities in West Africa, Accra, the capital of Ghana, and Lagos, the largest city of Nigeria, have significant problems with substandard pharmaceuticals. Both have actively combated the problem in recent years, particularly by screening products on the market using the Global Pharma Health Fund e.V. Minilab® protocol. Random sampling of medicines from the two cities at least twice over the past 30 months allows a tentative assessment of whether improvements in drug quality have occurred. Since intelligence provided by investigators indicates that some counterfeit producers may be adapting products to pass Minilab tests, the results are compared with those from a Raman spectrometer and discrepancies are discussed. Methods Between mid-2007 and early-2010, samples of anti-malarial drugs were bought covertly from pharmacies in Lagos on three different occasions (October 2007, December 2008, February 2010), and from pharmacies in Accra on two different occasions (October 2007, February 2010). All samples were tested using the Minilab® protocol, which includes disintegration and active ingredient assays as well as visual inspection, and most samples were also tested by Raman spectrometry. Results In Lagos, the failure rate in the 2010 sampling fell to 29% of the 2007 finding using the Minilab® protocol, 53% using Raman spectrometry, and 46% using visual inspection. In Accra, the failure rate in the 2010 sampling fell to 54% of the 2007 finding using the Minilab® protocol, 72% using Raman spectrometry, and 90% using visual inspection. Conclusions The evidence presented shows that drug quality is probably improving in both cities, especially Lagos, since major reductions of failure rates over time occur with all means of assessment. Many more samples failed when examined by Raman spectrometry than by Minilab® protocol. The discrepancy is most likely caused by the two techniques measuring different aspects of the medication and hence the discrepancy

Cobertura de los sistemas de pensiones y factores asociados al acceso a una pensión de jubilación en México

PubMed Central

Murillo-López, Sandra; Venegas-Martínez, Francisco

2016-01-01

Resumen Objetivos: obtener estimaciones de indicadores de cobertura de las pensiones por jubilación o retiro para la población mexicana de 65 y más años, y evaluar el impacto que tienen los sistemas de pensiones en las transiciones al retiro de los adultos en edades medias y avanzadas en México. Para ello se utilizan datos microeconómicos provenientes de la Encuesta Nacional de Salud y Envejecimiento. Mediante análisis econométrico se identifican los factores sociodemográficos, económicos, laborales e institucionales que están asociados al acceso a una pensión de jubilación, o bien, a la dependencia de otras fuentes de ingresos. Se encontró que, en México, las transiciones al retiro del mercado de trabajo en las etapas avanzadas del ciclo de vida son limitadas debido a las características eminentemente contributivas de los esquemas de pensiones, los cuales favorecen a la población con trayectorias laborales formales y más estables asociadas a: características de género, oportunidades educativas y posibilidades de inserción en el mercado laboral. PMID:27524936

Sedimentation survey of Lago Loco, Puerto Rico, March 2000

USGS Publications Warehouse

Soler-López, Luis R.

2002-01-01

Lago Loco, a small reservoir property of the Puerto Rico Electric Power Authority and part of the Southwestern Puerto Rico Project, has lost 64 percent of its original storage capacity. In 1951, the original storage capacity was about 2.40 million cubic meters, decreasing to 1.43 million cubic meters in 1986 and to 0.87 million cubic meters in March 2000. The storage loss or longterm sedimentation rate increased from 27,714 cubic meters per year from the period of 1951 to 1986 to 31,224 cubic meters per year for the period of 1951 to 2000. This represents a capacity loss of about 1.1 percent per year for the period of 1951 to 1986 and 1.3 percent per year for 1951 to 2000. The trapping efficiency of the reservoir was about 92 percent in 1951, decreasing to about 87 percent in 1986, and to about 80 percent in March 2000. The sediment yield of the net sediment- contributing drainage area increased from 1,504 megagrams per square kilometer per year between 1951 and 1986 to 1,774 megagrams per square kilometer per year between 1951 and 2000, or about 18 percent. At the current sedimentation rate of the reservoir, the life expectancy of Lago Loco is about 28 more years or until the year 2028.

Age and extent of the Ilopango TBJ Tephra inferred from a Holocene chronostratigraphic reference section, Lago De Yojoa, Honduras

USGS Publications Warehouse

Mehringer, P.J.; Sarna-Wojcicki, A. M.; Wollwage, L.K.; Sheets, P.

2005-01-01

Eruption of central El Salvador's Ilopango Volcano early in the first millennium A.D. caused death, cultural devastation, and exodus of southern Mesoamericans. It also left a time-stratigraphic marker in western El Salvador and adjacent Guatemala - the Ilopango Tierra Blanca Joven, or TBJ tephra. Mineral suites and major element abundances identify a silicic volcanic ash in cores from Lago de Yojoa, Honduras, as Ilopango TBJ. This extends its reported range more than 150 km to the northeast. Analyses of glass from the TBJ tephra from the Chalchuapa archaeological site, El Salvador, and from Lago de Yojoa, Honduras, establish the first major element reference fingerprint for the TBJ tephra. The Lago de Yojoa cores also hold two previously undated trachyandesitic tephra layers originating from the nearby Lake Yojoa Volcanic Field. One fell shortly before 11,000 14C yr B.P. and the other about 8600 14C yr B.P. ?? 2004 University of Washington. All rights reserved.

Knowledge, attitude and practice towards child adoption amongst women attending infertility clinics in Lagos State, Nigeria

PubMed Central

Kofoworola, Odeyemi

2011-01-01

Abstract Background Child adoption is a recommended alternative form of infertility management. Infertility is of public health importance in Nigeria and many other developing nations. This is a result of its high prevalence and especially because of its serious social implications as the African society places a passionate premium on procreation in any family setting. Objectives The aim of this study was to determine the knowledge, attitude and practice of child adoption amongst women attending infertility clinics in teaching hospitals in Lagos State and to determine the factors that influence their attitude and practice towards it. Method A cross-sectional descriptive design was used. Data were collected by using a structured questionnaire which was interviewer-administered. The study was conducted in the two teaching hospitals in Lagos State (LUTH [Lagos University Teaching Hospital] and LASUTH [Lagos State University Teaching Hospital]) from amongst 350 women attending the gynaecological clinics. All the patients under management for infertility at the gynaecology clinics during the period of the study were interviewed. Results Many respondents (85.7%) had heard of child adoption and 59.3% of them knew the correct meaning of the term. More than half of the respondents (68.3%) said that they could love an adopted child but less than half of them (33.7%) were willing to consider adoption. Only 13.9% has ever adopted a child. The major reason given for their unwillingness to adopt was their desire to have their own biological child. Factors that were favourable towards child adoption were Igbo tribe identity, an age above 40 years, duration of infertility above 15 years, and knowing the correct meaning of child adoption. Conclusion There is a poor attitude to adoption even amongst infertile couples. Interventions need to be implemented to educate the public on child adoption, to improve their attitude towards adoption and to make it more acceptable.

Dam failure analysis for the Lago de Matrullas Dam, Orocovis, Puerto Rico

USGS Publications Warehouse

Torres-Sierra, Heriberto; Gómez-Fragoso, Julieta

2015-01-01

Results from the simulated dam failure of the Lago de Matrullas Dam using the HEC–RAS model for the 6- and 24-hour PMP events showed peak discharges at the dam of 3,149.33 and 3,604.70 m3/s, respectively. Dam failure during the 100-year-recurrence, 24-hour rainfall event resulted in a peak discharge of 2,103.12 m3/s directly downstream from the dam. Dam failure under sunny day conditions produced a peak discharge of 1,695.91 m3/s at the dam assuming the antecedent lake level was at the morning-glory spillway invert elevation. Flood-inundation maps prepared as part of the study depict the flood extent and provide valuable information for preparing an Emergency Action Plan. Results of the failure analysis indicate that a failure of the Lago de Matrullas Dam could cause flooding to many of the inhabited areas along stream banks from the Lago de Matrullas Dam to the mouth of the Río Grande de Manatí. Among the areas most affected are the low-lying regions in the vicinity of the towns of Ciales, Manatí, and Barceloneta. The delineation of the flood boundaries near the town of Barceloneta considered the effects of a levee constructed during 2000 at Barceloneta in the flood plain of the Río Grande de Manatí to provide protection against flooding to the near-by low-lying populated areas. The results showed overtopping can be expected in the aforementioned levee during 6- and 24-hour probable-maximum-precipitation dam failure scenarios. No overtopping of the levee was simulated, however, during dam failure scenarios under the 100-year recurrence, 24-hour rainfall event or sunny day conditions.

Iron deficiency anaemia among apparently healthy pre-school children in Lagos, Nigeria.

PubMed

Akodu, Olufemi S; Disu, Elizabeth A; Njokanma, Olisamedua F; Kehinde, Omolara A

2016-03-01

Iron deficiency, and specifically iron deficiency anaemia, remains one of the most severe and important nutritional deficiencies in the world today. To estimate the prevalence and associated factors for iron deficiency anaemia among pre-school children in Lagos. The study was conducted from December 2009 to February 2010 at the outpatient clinics of Lagos State University Teaching Hospital, Lagos. Serum iron, total iron binding capacity, transferrin saturation and serum ferritin were assayed in subjects. The primary outcome measured was iron deficiency anaemia established based on the following criteria: hemoglobin <11.0 g/dl1 plus 2 or more of the following: MCV <70fl, transferrin saturation <10% or serum ferritin <15ng/dL. Statistical analysis included Pearson Chi square analysis and logistic regression analysis. A total of 87 apparently healthy subjects were recruited. Only one subject had iron depletion and this child belonged to the ≤ 2 years age category. None of the recruited subjects had iron deficiency without anaemia. Nine of the study subjects (10.11%) had iron deficiency anaemia. The prevalence of iron deficiency anaemia was significantly higher among younger age group than in the older age group (19.1% Vs 2.1%, p = 0.022). The prevalence of iron deficiency anaemia was significantly higher among subjects with weight-for-age, and weight-for-height Z scores below two standard scores (83.3% and 75.0% respectively, p = <0.001 and 0.001 respectively). The overall prevalence of iron deficiency anaemia among study subjects was 10.11%. Iron deficiency anaemia was more common in children aged two years and below. Weight-for-age and weight-for-height Z scores below minus two standard scores were strongly associated with iron deficiency anaemia.

Estimating sectoral pollution load in Lagos by Industrial Pollution Projection System (IPPS).

PubMed

Oketola, A A; Osibanjo, O

2007-05-15

Sensitivity to environmental issues brought about increasing pressure from local community, groups, environmental organizations and government regulators on industries to reduce their pollutant emissions. In this study, Industrial Pollution Projection System (IPPS), which was developed by the Infrastructure and Environment Team of the World Bank, was used to estimate pollution load in ton/yr (with respect to employment) of industrial sectors in Lagos. The IPPS was developed to exploit the fact that the scale of industrial activity, its sectorial composition, and the process technologies, employed in production, heavily affect industrial pollution. Available data, from Manufacturer's Association of Nigeria (M.A.N.) for the years 1997-2002 was used for the estimation. From the cumulative ranking of the pollution load (ton/yr) estimate to all media (i.e. air, land, and water), Chemical and Pharmaceutical (CPH) sector is the highest polluting sector, followed by Basic Metal (BML), Domestic and Industrial Plastics (DIP), and Food, Beverage and Tobacco (FBT) sectors. Some of these sectors have the highest number of employees, and also appeared as the most polluting sectors in Lagos.

Reprint of Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

NASA Astrophysics Data System (ADS)

Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

2016-12-01

Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P < 0.05) across the wetland areas. Also, dissolved inorganic carbon (DIC) contributed to most of the total dissolved solids (TDS) since only DIC correlated significantly with TDS (r = 0.889; P = 0.05, n = 12) and TS (r = 0.891; P = 0.05, n = 12), suggesting a strong capacity for carbon sequestration and carbon sink across the wetland areas. None of the encountered vegetation species are in the vulnerable category of the International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local

A workshop on medical ethics at the College of Medicine, Lagos University.

PubMed

Olukoya, A A

1984-12-01

As part of an effort to improve the teaching of medical ethics in the College of Medicine, Lagos University two-day workshops were organised. Participants included people from various walks of life, for example politicians, lawyers, doctors, and patients. The workshops were quite successful, and have led to more extensive teaching of medical ethics in the college.

Sistema Planeta-Satélite. Simulación orbital y potenciales gravitatorios

NASA Astrophysics Data System (ADS)

Medina, C.; Carrillo, M.

Se presenta un programa (desarrollado en Quick Basic 4.5) que simula, en tres dimensiones, el movimiento orbital de un satélite (o luna) alrededor de un planeta, al tiempo que calcula y grafica, en un plano, el potencial gravitatorio del sistema en función de la distancia al planeta. Para la simulación orbital, se emplea la matriz de transformación entre el sistema del planeta y el plano orbital. Para el cálculo y graficación del potencial se aplica un desarrollo en serie hasta el segundo orden, que da cuenta del efecto de achatamiento de los polos, en caso de que éste exista. Las longitudes de los ejes del planeta, la masa de éste y del satélite, sus tamaños aparentes, y los parámetros orbitales son introducidos por el usuario.

Geology, petrology and geochronology of the Lago Grande layered complex: Evidence for a PGE-mineralized magmatic suite in the Carajás Mineral Province, Brazil

NASA Astrophysics Data System (ADS)

Teixeira, Antonio Sales; Ferreira Filho, Cesar Fonseca; Giustina, Maria Emilia Schutesky Della; Araújo, Sylvia Maria; da Silva, Heloisa Helena Azevedo Barbosa

2015-12-01

The Lago Grande and Luanga mafic-ultramafic complexes are part of a cluster of PGE-mineralized layered intrusions located in the Carajás Mineral Province (CMP) in the Amazonian Craton. The Lago Grande Complex is a NE-trending medium-size (12-km-long and average 1.7-km-wide) layered intrusion consisting mainly of mafic cumulate rocks (Mafic Zone) and minor ultramafic cumulates (Ultramafic Zone). Geological sections indicate that igneous layers are overturned, such that the Ultramafic Zone overly the Mafic Zone. The Ultramafic Zone, about 4 km long and 500 m wide, comprises an up to 250 m-thick sequence of interlayered harzburgite and orthopyroxenite at the base and orthopyroxenite at the top. The Mafic Zone consists of a monotonous sequence of gabbroic rocks with an estimated thickness of up to 1000 m in the central part. Primary igneous minerals of the Lago Grande Complex are partially replaced by metamorphic assemblages that indicate temperatures up to the amphibolite facies of metamorphism. This metamorphic alteration is heterogeneous and characterized by an extensive hydration that largely preserves primary textures and bulk chemical composition. The composition of the parental magma of the Lago Grande Complex has been inferred from the crystallization sequences of the intrusion and lithogeochemistry of cumulate rocks. The compositional range of cumulus Ol (Fo82.5-85.7) is consistent with a moderately primitive composition for the parental magma. Cumulus minerals in the layered rocks indicate that the sequence of crystallization in the Lago Grande Complex consists of Ol + Chr, Opx + Chr, Opx, Opx + Pl and Opx + Pl + Cpx. The early crystallization of Opx relative to Cpx suggests that the primary magma was silica saturated. Mantle-normalized alteration-resistant trace element profiles of gabbroic rocks are fractionated, as indicated by relative enrichment in LREE and Th, with pronounced negative Nb and Ta anomalies. Nd isotopic data obtained for both mafic and

Hepatic pathologies in the brackish water catfish (Chrysichthys nigrodigitatus) from contaminated locations of the Lagos lagoon complex

USGS Publications Warehouse

Olarinmoye, O.; Taiwo, V.; Clarke, E.; Kumolu-Johnson, C.; Aderinola, O.; Adekunbi, F.

2010-01-01

Several toxicological studies into the effects of aquatic pollutants on the liver of teleost fish exist in literature. The focus on the liver in these studies is predicated on its central nature in the scheme of biotransformation and excretion of xenobiotics following exposure in polluted water bodies. As a consequence of the latter primary role of the liver in these processes it is regarded as a predilective site for the sub lethal effects of xenobiotics on the organism usually detectable at histological level. Hepatic histopathology recorded in livers from feral populations of the brackish water catfish Chrysichthys nigrodigitatus from locations on the Lagos lagoon complex with significant anthropogenic inputs from denizen populations and industries are presented. Liver sections from sixty specimens from two locations on the Lagos lagoon complex (Badagry lagoon: 6??24'N, 2??56'E; and Lagos lagoon: 6??29'N, 3??22'E) were analysed. Observed pathologies included hydropic degeneration (58%), portal / sinusoidal congestion (33%), hepatic necrosis (26%), hemosiderosis (12%) and foci of cellular alterations (FCA's). No obvious oncologic features were observed; the presence of the hydropic Vacuolation lesion was taken as prelude to the development of neoplasms and discussed as such. ?? 2009, Penkala Bt., Budapest, Hungary.

The knowledge, perceptions and practice of pharmacovigilance amongst community pharmacists in Lagos state, south west Nigeria.

PubMed

Oreagba, I A; Ogunleye, O J; Olayemi, S O

2011-01-01

Community Pharmacists both have an important responsibility in monitoring the ongoing safety of medicines and are widely accessible to do it. This study aims to investigate the knowledge, perceptions and practice of Pharmacovigilance amongst community pharmacists in Lagos State, South West Nigeria A cross-sectional observational survey was used in this study. A multistage random sampling technique was employed in the selection of 420 community pharmacies in Lagos. About 55% of respondents have ever heard of the word 'Pharmacovigilance' out of which less than half (representing only 18% of all respondents) could define the term 'Pharmacovigilance'. Forty percent of the respondents stated that patients reported ADRs to them at least once a month, and 20% reported to the relevant authorities. However only 3% of respondents actually reported an ADR to the National Pharmacovigilance Centre. The most important reason for poor reporting was lack of knowledge about how to report ADRs (44.6%).Meanwhile, 90% of respondents believed that the role of the pharmacists in ADR reporting was important. Most community pharmacists were willing to practice pharmacovigilance if they were trained. Community pharmacists in Lagos had poor knowledge about pharmacovigilance. Reporting rate was also poor. There is an urgent need for educational programs to train pharmacists about pharmacovigilance and ADR reporting. Copyright © 2010 John Wiley & Sons, Ltd.

Phylogeny of Lagos bat virus: challenges for lyssavirus taxonomy.

PubMed

Markotter, W; Kuzmin, I; Rupprecht, C E; Nel, L H

2008-07-01

Lagos bat virus (LBV) belongs to genotype 2 of the Lyssavirus genus. The complete nucleoprotein (N), phosphoprotein (P), matrixprotein (M) and glycoprotein (G) genes of 13 LBV isolates were sequenced and phylogenetically compared with other lyssavirus representatives. The results identified three different lineages of LBV. One of these lineages demonstrated sufficient sequence diversity to be considered a new lyssavirus genotype (Dakar bat lyssavirus). The suggested quantitative separation of lyssavirus genotypes using the N, P, M and G genes was also investigated using P-distances matrixes. Results indicated that the current criteria should be revised since overlaps between intergenotypic and intragenotypic variation occur.

Use of Remote Sensing and Local Knowledge for Geoconservation of Regiao dos Lagos, Brazil

NASA Astrophysics Data System (ADS)

Avelar, S.; Vasconcelos, G.; Mansur, K. L.; Anjos, S. C.

2013-12-01

A series of lagoons can be found along the coastline of Rio de Janeiro, in the so-called Regiao dos Lagos. The lagoons differ in size, physicochemical, sedimentological and biological characteristics. Rare examples of litifying microbialites that produce stromatolites, the oldest fossils on Earth, can be found living in this lagoon system. The occurrence of stromatolites in the region is of great scientific interest because it enables the study of possible analogues of the earliest life on Earth. However, this region has been suffering from intense human activities and degradations. Geoconservation planning requires an assessment of the characteristics of the region and its potential threats. The primary goal of this study is to assess physical environmental changes and anthropogenic impacts over the last four decades in Regiao dos Lagos. Using a broad integrative assessment combining remote sensing, GIS, field studies and local knowledge of communities, land-cover and land-use classes were identified, as well as the main human activities impacting the environment. The seasonal and weekend tourism and urban sprawl in this coastal area of Rio de Janeiro triggers the occupation of new areas and the removal of natural vegetation, especially on lagoon margins. This disorderly occupation by an ever increasing population, with both legal and illegal constructions and the subsequent overload of the local infrastructure, e.g. increase of electrical energy consumption, volume of vehicles, pollution in air, water and soil and problems with water supply and wastewater treatment, are hastening the gradual degradation of the lake ecosystem. The main driving forces to environmental changes over the last four decades in Regiao dos Lagos were the change of dense vegetation, saline and bare soil classes into built-up areas, adding to the poor waste treatment and inadequate sewage disposal. This analysis provides a basis for a better control of anthropogenic impacts and

Psycho-Demographic Correlates of Behaviour towards Seeking Counselling Intervention among Workers in Lagos, Nigeria

ERIC Educational Resources Information Center

Gesinde, Abiodun Matthew; Sanu, Oluwafunto Jolade

2015-01-01

This study sought to examine the impact which age, gender and psychological adjustment have on behaviour towards seeking professional counselling intervention. Multistage sampling technique was employed to select a total of three hundred workers across Lagos metropolis. The ex post facto research design was adopted for the study. Inventory of…

Perceptions and Concerns about Inclusive Education among Students with Visual Impairments in Lagos, Nigeria

ERIC Educational Resources Information Center

Brydges, Colton; Mkandawire, Paul

2017-01-01

This article examines the perceptions of inclusive education in Lagos, Nigeria, based upon in-depth interviews conducted with students with visual impairments during the month of July 2013. The results and discussions are situated within critical disability theory. Despite decades of inclusive education policies, the findings of the study show…

Asymptomatic bacteriuria among antenatal women in Lagos.

PubMed

Olamijulo, Joseph Ayodeji; Adewale, Chris Olu; Olaleye, Olalekan

2016-08-01

This cross-sectional study was undertaken to determine the prevalence of asymptomatic bacteriuria (ASB), the commonest bacterial isolates and the antibiotic sensitivity pattern among 556 pregnant women in Lagos University Teaching Hospital (LUTH), Nigeria. Women with a bacterial count over 100,000 colony-forming units per millilitre of the same organisms in paired urine samples were considered to have ASB. The prevalence of ASB was 14.6%. Klebsiella was the commonest micro-organism (39.2%) isolated. ASB was significantly associated with marital status, body mass index and parity. There was a significant relationship between urinary nitrites and ASB. The isolated organisms showed remarkable resistance to commonly prescribed antibiotics such as amoxicillin, cloxacillin and trimethoprim but good sensitivity to ofloxacin, gentamycin and ceftazidime. These facts have implications for the management of ASB in pregnancy.

Levels of Job Satisfaction and Performance of Sports Officers in Lagos State Secondary Schools

ERIC Educational Resources Information Center

Onifade, Ademola; Keinde, Idou; Kehinde, Eunice

2009-01-01

The purpose of this paper was to examine the relationship between job satisfaction levels of sports officers and sports performance of secondary schools in Lagos State. Data were collected from 200 subjects across 10 Local Education Districts. Job Descriptive Index was used to determine job satisfaction while performance in the Principals' Soccer…

Oral health care knowledge and practices of a group of deaf adolescents in Lagos, Nigeria.

PubMed

Oredugba, Folakemi A

2004-01-01

This study sought to determine the oral health care knowledge and practices of a group of deaf adolescents in Lagos. The study involved 50 students of Wesley School 1 for the Deaf, Lagos (26 males and 24 females, aged 10-19 years, mean 13.3 +/- 2.8). Information about previous dental care, oral hygiene, and snacking habits were obtained through a questionnaire and sign language by the teachers. Only 12 percent of pupils had received dental care. Eight percent and 72 percent, respectively, gave correct answers to causes of tooth decay and bleeding gums. Ninety-four percent brushed their teeth once daily, with no significant sex difference (P > .05). Reported dental problems include bleeding gums (36%), tooth discoloration, and tooth decay. The majority of pupils (60%) preferred biscuits and soft drinks as snacks. More than 90 percent were willing to have a dental check-up. The oral health knowledge and practices of this group of children will improve through a controlled school-based oral health education program.

Climate change in Lagos state, Nigeria: what really changed?

PubMed

Sojobi, Adebayo Olatunbosun; Balogun, Isaac Idowu; Salami, Adebayo Wahab

2015-10-01

Our study revealed periodicities of 2.3 and 2.25 years in wet and dry seasons and periodicities of 2 to 5 years on seasonal and annual timescales. Minimum temperature (Tmin), maximum temperature (Tmax) and evaporation recorded increases of 2.47, 1.37 and 28.37 %, respectively, but a reduction of 19.58 % in rainfall on decadal timescale. Periodicity of 8 to 12 years was also observed in annual Tmax. Cramer's test indicated a warming trend with significant Tmax increase in February, April, July, August, October and November during 2000-2009 on decadal monthly timescale, a significant decline in Summer rainfall but significant Tmax increase in Spring, Autumn and Winter on decadal seasonal timescale. The low correlation of rainfall with temperature parameters and evaporation indicates that advection of moisture into Lagos State seems to be the dominant mechanism controlling rainfall within the State alongside other tropical and extra-tropical factors. In addition, our study revealed that the persistent state of minimum temperature often precedes the arrival and reversal of the phase of maximum temperature. Furthermore, our study also revealed that extreme and high variable rainfalls, which are associated with the increased warming trend, had periodicities of 1 to 3 years with a probability of 86.45 % of occurring every 3 years between April and September. It is recommended that government and private sector should give financial and technical supports to climate researches in order to appropriately inform policy making to improve the adaptive capacity and resilience of Lagos State against climate change impacts and guard against maladaptation.

Multi-stakeholder perspectives on access, availability and utilization of emergency obstetric care services in Lagos, Nigeria: A mixed-methods study

PubMed Central

Wright, Kikelomo; Sonoiki, Olatunji; Ilozumba, Onaedo; Ajayi, Babatunde; Okikiolu, Olawunmi; Akinola, Oluwarotimi

2017-01-01

Globally, Nigeria is the second most unsafe country to be pregnant, with Lagos, its economic nerve center having disproportionately higher maternal deaths than the national average. Emergency obstetric care (EmOC) is effective in reducing pregnancyrelated morbidities and mortalities. This mixed-methods study quantitatively assessed women’s satisfaction with EmOC received and qualitatively engaged multiple key stakeholders to better understand issues around EmOC access, availability and utilization in Lagos. Qualitative interviews revealed that regarding access, while government opined that EmOC facilities have been strategically built across Lagos, women flagged issues with difficulty in access, compounded by perceived high EmOC cost. For availability, though health workers were judged competent, they appeared insufficient, overworked and felt poorly remunerated. Infrastructure was considered inadequate and paucity of blood and blood products remained commonplace. Although pregnant women positively rated the clinical aspects of care, as confirmed by the survey, satisfaction gaps remained in the areas of service delivery, care organization and responsiveness. These areas of discordance offer insight to opportunities for improvements, which would ensure that every woman can access and use quality EmOC that is sufficiently available. PMID:29456825

Holocene glacier history of the Lago Argentino basin, Southern Patagonian Icefield

NASA Astrophysics Data System (ADS)

Strelin, Jorge A.; Kaplan, Michael R.; Vandergoes, Marcus J.; Denton, George H.; Schaefer, Joerg M.

2014-10-01

We present new geomorphic, stratigraphic, and chronologic data for Holocene glacier fluctuations in the Lago Argentino basin on the eastern side of the southern Patagonian Andes. Chronologic control is based on 14C and surface-exposure 10Be dating. After the Lateglacial maximum at 13,000 cal yrs BP, the large ice lobes that filled the eastern reaches of Lago Argentino retreated and separated into individual outlet glaciers; this recession was interrupted only by a stillstand or minor readvance at 12,200 cal yrs BP. The eight largest of these individual outlet glaciers are, from north to south: Upsala, Agassiz, Onelli, Spegazzini, Mayo, Ameghino, Perito Moreno, and Grande (formerly Frías). Holocene recession of Upsala Glacier exposed Brazo Cristina more than 10,115 ± 100 cal yrs BP, and reached inboard of the Holocene moraines in Agassiz Este Valley by 9205 ± 85 cal yrs BP; ice remained in an inboard position until 7730 ± 50 cal yrs BP. Several subsequent glacier readvances are well documented for the Upsala and Frías glaciers. The Upsala Glacier readvanced at least seven times, the first being a relatively minor expansion - documented only in stratigraphic sections - between 7730 ± 50 and 7210 ± 45 cal yrs BP. The most extensive Holocene advances of Upsala Glacier resulted in the deposition of the Pearson 1 moraines and related landforms, which are divided into three systems. The Pearson 1a advance occurred about 6000-5000 cal yrs BP and was followed by the slightly less-extensive Pearson 1b and 1c advances dated to 2500-2000 and 1500-1100 cal yrs BP, respectively. Subsequent advances of Upsala Glacier resulted in deposition of the Pearson 2 moraines and corresponding landforms, also separated into three systems, Pearson 2a, 2b, and 2c, constructed respectively at ˜700, >400, and <300 cal yrs BP to the early 20th century. Similar advances are also recorded by moraine systems in front of Grande Glacier and herein separated into the Frías 1 and Frías 2a, 2b

Isolation of Lagos bat virus from water mongoose.

PubMed

Markotter, Wanda; Kuzmin, Ivan; Rupprecht, Charles E; Randles, Jenny; Sabeta, Claude T; Wandeler, Alexander I; Nel, Louis H

2006-12-01

A genotype 2 lyssavirus, Lagos bat virus (LBV), was isolated from a terrestrial wildlife species (water mongoose) in August 2004 in the Durban area of the KwaZulu-Natal Province of South Africa. The virus isolate was confirmed as LBV by antigenic and genetic characterization, and the mongoose was identified as Atilax paludinosus by mitochondrial cytochrome b sequence analysis. Phylogenetic analysis demonstrated sequence homology with previous LBV isolates from South African bats. Studies performed in mice indicated that the peripheral pathogenicity of LBV had been underestimated in previous studies. Surveillance strategies for LBV in Africa must be improved to better understand the epidemiology of this virus and to make informed decisions on future vaccine strategies because evidence is insufficent that current rabies vaccines provide protection against LBV.

Sedimentation survey of Lago La Plata, Toa Alta, Puerto Rico, March–April 2015

USGS Publications Warehouse

Gómez-Fragoso, Julieta

2016-10-31

IntroductionLago La Plata is operated by the Puerto Rico Aqueduct and Sewer Authority (PRASA) and is part of the San Juan Metropolitan Water District. The reservoir serves a population of about 425,000 people. During 2013 the reservoir provided 0.307 million cubic meters (Mm3 ) of water per day (about 81 million gallons per day), which is equivalent to 31 percent of the total water demand for the metropolitan area (Wanda L. Molina, U.S. Geological Survey, written commun., 2015). The dam was constructed in 1974 and is located about 5 kilometers (km) south of the town of Toa Alta and 5 km north of the town of Naranjito (fig. 1). The drainage area upstream from the Lago La Plata dam is about 469 square kilometers (km2 ). The storage capacity at construction in 1974 was 26.84 Mm3 with a spillway elevation of 47.12 meters (m) above mean sea level (msl). Storage capacity was increased to 40.21 Mm3 in 1989 after the installation of bascule gates to provide a normal dam pool elevation at 52 m above msl (Puerto Rico Electric and Power Authority, 1979). The maximum height of the dam is about 40 m above the river bottom near the dam, and the intake structure consists of six 1.82-m-diameter ports facing upstream, with 6-m vertical spacing that begins at an elevation of 19 m above msl. The U.S. Geological Survey (USGS), in cooperation with the PRASA, conducted a bathymetric survey of the Lago La Plata reservoir during March and April 2015. The hydrographic survey was designed to provide an update of the reservoir storage capacity and sedimentation rate. Areas with substantial sediment accumulation are also discussed in this report. The results of the survey were used to prepare a bathymetric map showing the reservoir bottom (fig. 2) referenced with respect to the spillway elevation. This report also includes a summary of a previous bathymetric survey conducted in 2006 (Soler-López, 2008).

An Epidemiological Comparison of Parasitic Infection among Preschool Children in Four Areas in Lagos, Nigeria.

ERIC Educational Resources Information Center

Abidoye, R. O.

1995-01-01

Examined incidence of parasitic infections in school children in four contrasting areas of Lagos, Nigeria. Found that almost 40% of the infections identified were of the low socioeconomic status children. The 20 children from the higher socioeconomic status area, with the highest environmental sanitation, were without parasites. Twelve percent of…

Sedimentation survey of Lago Loíza, Trujillo Alto, Puerto Rico, July 2009

USGS Publications Warehouse

Soler-López, Luis R.; Licha-Soler, N.A.

2014-01-01

Lago Loíza is a reservoir formed at the confluence of Río Gurabo and Río Grande de Loíza in the municipality of Trujillo Alto in central Puerto Rico, about 10 kilometers (km) north of the town of Caguas, about 9 km northwest of Gurabo, and about 3 km south of Trujillo Alto (fig. 1). The Carraizo Dam is owned and operated by the Puerto Rico Aqueduct and Sewer Authority (PRASA), and was constructed in 1953 as a water-supply reservoir for the San Juan Metropolitan area. The dam is a concrete gravity structure that is located in a shallow valley and has a gently sloping left abutment and steep right abutment. Non-overflow sections flank the spillway section. Waterways include an intake structure for the pumping station and power plant, sluiceways, a trash sluice, and a spillway. The reservoir was built to provide a storage capacity of 26.8 million cubic meters (Mm3) of water at the maximum pool elevation of 41.14 meters (m) above mean sea level (msl) for the Sergio Cuevas Filtration Plant that serves the San Juan metropolitan area. The reservoir has a drainage area of 538 square kilometers (km2) and receives an annual mean rainfall that ranges from 1,600 to 5,000 millimeters per year (mm/yr). The principal streams that drain into Lago Loíza are the Río Grande de Loíza, Río Gurabo, and Río Cañas. Two other rivers, the Río Bairoa and Río Cagüitas, discharge into the Río Grande de Loíza just before it enters the reservoir. The combined mean annual runoff of the Río Grande de Loíza and the Río Gurabo for the 1960–2009 period of record is 323 Mm3. Flow from these streams constitutes about 89 percent of the total mean annual inflow of 364 Mm3 to the reservoir (U.S. Geological Survey, 2009). Detailed information about Lago Loíza reservoir structures, historical sediment accumulation, and a dredge conducted in 1999 are available in Soler-López and Gómez-Gómez (2005). During July 8–15, 2009, the U.S. Geological Survey (USGS) Caribbean Water Science

Sedimentation Survey of Lago Patillas, Puerto Rico, March 2007

USGS Publications Warehouse

Soler-López, Luis R.

2010-01-01

Lago Patillas is a reservoir located on the confluence of Rio Grande de Patillas and Rio Marin, in the municipality of Patillas in southern Puerto Rico, about 3 kilometers north of the town of Patillas and about 8 kilometers northeast of the town of Arroyo (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA) and was constructed in 1914 for the irrigation of croplands in the southern coastal plains of Puerto Rico along the towns of Arroyo, Guayama, Patillas, and Salinas. Irrigation releases are made through the outlet works into the Patillas Irrigation Canal that extends 32.2 kilometers from the Patillas dam to Rio Salinas. The dam is a semi-hydraulic earthfill with a structural height of 44.80 meters, a top width of 4.57 meters, a base width of 190.49 meters, and a crest length of 325.21 meters. The spillway structure is physically separated from the earthfill dam, has an elevation of 58.21 meters above mean sea level, and has three radial arm gates (Puerto Rico Electric Power Authority, 1979). The reservoir impounds the waters of the Rio Grande de Patillas and Rio Marin. The reservoir has a drainage area of 66.3 square kilometers. Additional information and operational procedures are listed in Soler-Lopez and others (1999). During March 14-15, 2007, the U.S. Geological Survey (USGS), Caribbean Water Science Center (CWSC), in cooperation with the PREPA conducted a bathymetric survey of Lago Patillas to update the reservoir storage capacity and update the reservoir sedimentation rate by comparing the 2007 bathymetric survey data with previous 1997 data. The purpose of this report is to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since April 1997.

Holocene climate variability and anthropogenic impacts from Lago Paixban, a perennial wetland in Peten, Guatemala

USGS Publications Warehouse

Wahl, David B.; Hansen, Richard D.; Byrne, Roger; Anderson, Lysanna; Schreiner, T.

2016-01-01

Analyses of an ~ 6 m sediment core from Lago Paixban in Peten, Guatemala, document the complex evolution of a perennial wetland over the last 10,300 years. The basal sediment is comprised of alluvial/colluvial fill deposited in the early Holocene. The absence of pollen and gastropods in the basal sediments suggests intermittently dry conditions until ~ 9000 cal yr. BP (henceforth BP) when the basin began to hold water perennially. Lowland tropical forest taxa dominated the local vegetation at this time. A distinct band of carbonate dating to ~ 8200 BP suggests regionally dry conditions, possibly associated with the 8.2 ka event. Wetter conditions during the Holocene Thermal Maximum are indicated by evidence of a raised water level and an open water lake. The timing of this interval coincides with strengthening of the Central American Monsoon. An abrupt change at 5500 BP involved the development of a sawgrass marsh and onset of peat deposition. The lowest recorded water levels date to 5500–4500 BP. Pollen, isotope, geochemical, and sedimentological data indicate that the coring site was near the edge of the marsh during this period. A rise in the water table after 4500 BP persisted until around 3500 BP. Clay marl deposition from 3500 to 210 BP corresponds to the period of Maya settlement. An increase in δ13C, the presence of Zea pollen, and a reduction in the percentage of forest taxa pollen indicate agricultural activity at this time. In contrast to several nearby paleoenvironmental studies, proxy evidence from Lago Paixban indicates human presence through the Classic/Postclassic period transition (~ 1000 BP) and persisting until the arrival of Europeans. Cessation of human activity around 210 BP resulted in local afforestation and the re-establishment of the current sawgrass marsh at Lago Paixban.

Holocene climate variability and anthropogenic impacts from Lago Paixban, a perennial wetland in Peten, Guatemala

NASA Astrophysics Data System (ADS)

Wahl, David; Hansen, Richard D.; Byrne, Roger; Anderson, Lysanna; Schreiner, Thomas

2016-03-01

Analyses of an 6 m sediment core from Lago Paixban in Peten, Guatemala, document the complex evolution of a perennial wetland over the last 10,300 years. The basal sediment is comprised of alluvial/colluvial fill deposited in the early Holocene. The absence of pollen and gastropods in the basal sediments suggests intermittently dry conditions until 9000 cal yr. BP (henceforth BP) when the basin began to hold water perennially. Lowland tropical forest taxa dominated the local vegetation at this time. A distinct band of carbonate dating to 8200 BP suggests regionally dry conditions, possibly associated with the 8.2 ka event. Wetter conditions during the Holocene Thermal Maximum are indicated by evidence of a raised water level and an open water lake. The timing of this interval coincides with strengthening of the Central American Monsoon. An abrupt change at 5500 BP involved the development of a sawgrass marsh and onset of peat deposition. The lowest recorded water levels date to 5500-4500 BP. Pollen, isotope, geochemical, and sedimentological data indicate that the coring site was near the edge of the marsh during this period. A rise in the water table after 4500 BP persisted until around 3500 BP. Clay marl deposition from 3500 to 210 BP corresponds to the period of Maya settlement. An increase in δ13C, the presence of Zea pollen, and a reduction in the percentage of forest taxa pollen indicate agricultural activity at this time. In contrast to several nearby paleoenvironmental studies, proxy evidence from Lago Paixban indicates human presence through the Classic/Postclassic period transition ( 1000 BP) and persisting until the arrival of Europeans. Cessation of human activity around 210 BP resulted in local afforestation and the re-establishment of the current sawgrass marsh at Lago Paixban.

CT-detected intracranial hemorrhage among patients with head injury in Lagos, Nigeria.

PubMed

Eze, Cletus Uche; Abonyi, Livinus Chibuzo; Olowoyeye, Omodele; Njoku, Jerome; Ohagwu, Christopher; Babalola, Sherifat

2013-01-01

To evaluate the computed tomography (CT) findings of intracranial hemorrhage among patients with head trauma in Lagos, Nigeria. In this retrospective, cross-sectional study, a convenience sample of 500 patients with head trauma who had diagnostic cranial CT scans was selected. All the radiological reports and CT scans of patients with head trauma were retrieved in the hospitals selected as study sites. The reports were sorted into 2 groups - normal findings and intracranial bleeding. The reports of intracranial bleeding were sorted again into different classes of intracranial bleeding as identified by the radiologist who reported it. All data were analyzed using the Epi Info public domain software package. The chi-square test was used to measure the statistical significance of study results at P < .05. Most of the study subjects (68%) were men. Traffic accidents accounted for 44% of all the head traumas found in the study, and 58% of the head traumas resulted in intracranial bleeding. Among the hemorrhages found, 37% were intracerebral, 25% were subdural, 16% were intraventricular, 15% were subarachnoid, and 7% were epidural. Intracranial hemorrhage was a common consequence of acute head trauma sustained from traffic accidents in the population studied, with intracerebral hemorrhage being the most prevalent type. Traffic accidents are the main cause of acute head trauma in Lagos, Nigeria. The use of CT for early diagnosis of intracranial hemorrhage appears justifiable.

Isolation of Lagos Bat Virus from Water Mongoose

PubMed Central

Markotter, Wanda; Kuzmin, Ivan; Rupprecht, Charles E.; Randles, Jenny; Sabeta, Claude T.; Wandeler, Alexander I.

2006-01-01

A genotype 2 lyssavirus, Lagos bat virus (LBV), was isolated from a terrestrial wildlife species (water mongoose) in August 2004 in the Durban area of the KwaZulu-Natal Province of South Africa. The virus isolate was confirmed as LBV by antigenic and genetic characterization, and the mongoose was identified as Atilax paludinosus by mitochondrial cytochrome b sequence analysis. Phylogenetic analysis demonstrated sequence homology with previous LBV isolates from South African bats. Studies performed in mice indicated that the peripheral pathogenicity of LBV had been underestimated in previous studies. Surveillance strategies for LBV in Africa must be improved to better understand the epidemiology of this virus and to make informed decisions on future vaccine strategies because evidence is insufficent that current rabies vaccines provide protection against LBV. PMID:17326944

Land-use effects on erosion, sediment yields, and reservoir sedimentation: a case study in the Lago Loiza Basin, Puerto Rico

USGS Publications Warehouse

Gellis, A.C.; Webb, R.M.T.; McIntyre, S.C.; Wolfe, W.J.

2006-01-01

 Lago Loíza impounded in 1953 to supply San Juan, Puerto Rico, with drinking water; by 1994, it had lost 47% of its capacity. To characterize sedimentation in Lago Loíza, a study combining land-use history, hillslope erosion rates, and subbasin sediment yields was conducted. Sedimentation rates during the early part of the reservoir’s operation (1953– 1963) were slightly higher than the rates during 1964–1990. In the early history of the reservoir, cropland comprised 48% of the basin and erosion rates were high. Following economic shifts during the 1960s, cropland was abandoned and replaced by forest, which increased from 7.6% in 1950 to 20.6% in 1987. These land-use changes follow a pattern similar to the northeastern United States. Population in the Lago Loíza Basin increased 77% from 1950 to 1990, and housing units increased 194%. Sheetwash erosion measured from 1991 to 1993 showed construction sites had the highest sediment concentration (61,400 ppm), followed by cropland (47,400 ppm), pasture (3510 ppm), and forest (2050 ppm). This study illustrates how a variety of tools and approaches can be used to understand the complex interaction between land use, upland erosion, fluvial sediment transport and storage, and reservoir sedimentation. 

ATTITUDES AND ACCEPTANCE OF NIGERIANS TOWARDS VASECTOMY--A COMPARISON OF MARRIED MEN AND WOMEN IN LAGOS.

PubMed

Tijani, K H; Ojewola, R W; Yahya, G L; Oluwole, A A; Odusanya, B

2013-03-01

Nigeria with a growth rate of 28%, accounts for over two thirds of the West African population. It also has one of the highest maternal mortality rates in the world with contraceptive prevalence among married couples less than 10%. Despite its safety and efficacy vasectomy appears to be unpopular in our environment. To assess the perception and acceptance of married men and women towards vasectomy and the influence of the spouse on the man's decision to accept or reject vasectomy. A cross sectional questionnaire based study. With an estimated population of 20 million, Lagos is the most cosmopolitan and urbanised city in Nigeria and accounts for 65% of all commercial activities in the country. Virtually all the tribes in Nigeria are represented in the city. Literate pregnant women recruited from the antenatal clinics and literate new fathers. All subjects were recruited from three health facilities in the Lagos metropolis. Twenty seven point five and twenty one percent of the men and women respectively had a good Knowledge of vasectomy while 49.1% and 19% of all men and women respectively with good knowledge would accept vasectomy (or agree for their spouses to have the procedure). Overall acceptance rates for men and women were 26 and 13.5% respectively while 92% of men who can opt for vasectomy will only do so if their spouses agree. Knowledge about vasectomy was the strongest single factor influencing the acceptance of vasectomy (p= 0.013) with stronger correlation among men than women (p=0.005 vrs p=.0.023). Knowledge and acceptance of vasectomy is significantly better in males than female Nigerians living in Lagos.

Evidence of Lagos bat virus circulation among Nigerian fruit bats.

PubMed

Dzikwi, Asabe A; Kuzmin, Ivan I; Umoh, Jarlath U; Kwaga, Jacob K P; Ahmad, Aliyu A; Rupprecht, Charles E

2010-01-01

During lyssavirus surveillance, 350 brains from four species of fruit bats and one species of insectivorous bat were collected from seven locations in Northern Nigeria during May to October, 2006. Lyssavirus antigen was not detected in the brains, and isolation attempts in mice were unsuccessful. However, serologic tests demonstrated the presence of lyssavirus-neutralizing antibodies in bat sera. Of 140 sera tested, 27 (19%) neutralized Lagos bat virus, and two of these additionally neutralized Mokola virus. The positive samples originated from the straw-colored fruit bat (Eidolon helvum) and the Gambian epaulet bat (Epomophorus gambianus). No neutralizing activity was detected against other lyssaviruses including rabies, Duvenhage, and West Caucasian bat viruses.

"Their days are spent in gambling and loafing, pimping for prostitutes, and picking pockets": male juvenile delinquents on Lagos Island, 1920s - 1960s.

PubMed

Heap, Simon

2010-01-01

In recent times, Lagos Island has been hit by a cyclical crescendo of juvenile crime perpetrated by "Area Boys," jobless youths who deal in robbery, extortion, and blackmail. Such deviant behavior has historical roots back to colonial times, when youths labeled "alkali boys," "boma boys," and "cowboys" roamed the heart of the capital of Britain's colony of Nigeria between the 1920s and 1960s. Examining the various types of juvenile delinquents on Lagos Island, this article explores the urban experience of criminally minded youths through exploration of street-life, vagrancy, criminality, and public reactions.

Trip to Lago Nero (Tusco-Emilian Apennine, Italy): How has our Apennine been changing?

NASA Astrophysics Data System (ADS)

Papini, Piera; Vergari, Simone

2014-05-01

The sharp division of disciplines in Italian Secondary school is a problem which hinders the natural learning of pupils. At the end of the 1st education cycle, candidates must stand six written tests and an oral exam during which they present a topic that includes a lot of disciplines and that they develop unifying what they have been taught fragmentarily. Climate changes that are taking place and the use of Earth resources are a significant topic suitable for a multidisciplinary as well as interdisciplinary approach. Thanks to the Region of Tuscany, which has financed the Educational Contract " An agreement for water" (2012-2015), we could develop this module which involves 14 years old students and is focused on the climate change evidence in a lake, Lago Nero, originated in the Tusco-Emilian Apennine during the development of an ancient Wurmian glacier. The didactical path includes: - lessons in the classroom on weather, climate and climate changes caused both by nature and by man. - A focus on Lago Nero - A trip to Lago Nero, observation of the landscape geomorphology: differences between fluvial valleys and glacial valleys, signs of remote events such as roche mountonnée or recent ones such as landslides and floods caused by intense rainfalls. Collection of samples. - Participation at a conference organized by the Region at San Giorgio Library in Pistoia ( http://rinnoviamoci2011.blogspot.it/ ) during which students met some administrators and talked with them. A video made by the pupils was presented on this occasion. http://www.icsfrankcarradori.it/studenti/ Further activities include: - Open day for families of the younger pupils, during which older pupils explained some of the activities carried out, included the module on Lago Nero. - identification of minerals (connection with Chemestry) - identification of rocks outcropping in the area of the lake: what do they tell about geologic history of our mountains? How can they reveal the age of a geologic

A Study of Power Relations in Doctor-Patient Interactions in Selected Hospitals in Lagos State, Nigeria

ERIC Educational Resources Information Center

Adam, Qasim

2014-01-01

This paper explores power relations in clinical interactions in Nigeria. It seeks to investigate the use of power between doctors and patients during consultations on patient-centred approach to medicine in selected public and private hospitals in Lagos State, Nigeria. The objective is to establish how doctors' projection of power, using the…

Reconstruction of full glacial environments and summer temperatures from Lago della Costa, a refugial site in Northern Italy

NASA Astrophysics Data System (ADS)

Samartin, Stéphanie; Heiri, Oliver; Kaltenrieder, Petra; Kühl, Norbert; Tinner, Willy

2016-07-01

Vegetation and climate during the last ice age and the Last Glacial Maximum (LGM, ∼23,000-19,000 cal BP) were considerably different than during the current interglacial (Holocene). Cold climatic conditions and growing ice-sheets during the last glaciation radically reduced forest extent in Europe to a restricted number of so-called ;refugia;, mostly located in the southern part of the continent. On the basis of paleobotanical analyses the Euganian Hills (Colli Euganei) in northeastern Italy have previously been proposed as one of the northernmost refugia of temperate trees (e.g. deciduous Quercus, Tilia, Ulmus, Fraxinus excelsior, Acer, Abies alba, Fagus sylvatica, Carpinus and Castanea) in Europe. In this study we provide the first quantitative, vegetation independent summer air temperature reconstruction for Northern Italy spanning the time ∼31,000-17,000 cal yr BP, which covers the coldest periods of the last glacial, including the LGM and Heinrich stadials 1 to 3. Chironomids preserved in a lake sediment core from Lago della Costa (7m a.s.l.), a small lake at the south-eastern edge of the Euganean Hills, allowed quantitative reconstruction of Full and Late Glacial summer air temperatures using a combined Swiss-Norwegian temperature inference model based on chironomid assemblages from 274 lakes. Chironomid and pollen evidence from Lago della Costa derives from finely stratified autochthonous organic gyttja sediments, which excludes major sediment mixing or reworking. After reconstructing paleo-temperatures, we address the question whether climate conditions were warm enough to permit the local survival of temperate tree species during the LGM and whether local expansions and pollen-inferred contractions of temperate tree taxa coincided with chironomid-inferred climatic changes. Our results suggest that chironomids at Lago della Costa have responded to major climatic fluctuations such as temperature decreases during the LGM and Heinrich stadials. The

Addressing the Multiple Drivers of Wetland Ecosystems Degradation in Lagos, Nigeria

NASA Astrophysics Data System (ADS)

Agboola, J.; Ndimele, P. E.; Odunuga, S.; Akanni, A.; Kosemani, B.; Ahove, M.

2015-12-01

Several body of knowledge have noted the importance of wetland ecosystems in climate moderation, resource supply and flood risk reduction amongst others. Relevant as it may, rapidly increasing population and uncontrolled urban development poses a challenge in some regions and require understanding of the ecosystem components and drivers of change over a long period of time. Thus, the main thrust of this paper is to analyse multiple drivers of wetland ecosystems degradation in the last 30 years in the Lagos megacity using field study, desktop review, satellite data and laboratory analysis. Key drivers identified includes: conversion of wetlands to settlements and waste sink, land use planning that neglects wetland conservation and restoration, ineffective legal status for wetlands, over exploitation leading to degradation and fragmentation of wetland ecosystems governance. In stemming further loss of this vital ecosystem, this study adopted and proposed respectively, the Drivers, Pressure, State, Impact and Response (DPSIR) and Integrated Planning Approach (IPA) frameworks in analysing policy and governance issues in wetland development. These analyses figured out amongst others, strict conservation and sustainable use of wetland resources, habitat restoration, climate adaptation measures, legal protection and wetland management institution as major responses to current multiple pressures facing wetland ecosystems in Lagos. For these frameworks to be made meaningful, weak coordination among government agencies and institutional capacity in implementation and law enforcement, unsustainable resource extraction by private/business organization and issues on alternative sources of income on the part of the local communities amongst others needs to be addressed.

Assessment of the Regenerative Potential of Organic Waste Streams in Lagos Mega-City

NASA Astrophysics Data System (ADS)

Opejin, Adenike Kafayat

There is never a better time for this study than now when Nigeria as a country is going through the worst time in power supply. In Lagos city about 12,000 tons of waste is generated daily, and is expected to increase as the city adds more population. The management of these waste has generated great concern among professionals, academia and government agencies. This study examined the regenerative management of organic waste, which accounts for about 45% of the total waste generated in Lagos. To do this, two management scenarios were developed: landfill methane to electricity and compost; and analyzed using data collected during field work and from government reports. While it is understood that landfilling waste is the least sustainable option, this study argued that it could be a viable method for developing countries. Using U.S EPA LandGEM and the IPCC model, estimates of capturable landfill methane gas was derived for three landfills studied. Furthermore, a 35-year projection of waste and landfill methane was done for three newly proposed landfills. Assumptions were made that these new landfills will be sanitary. It was established that an average of 919,480,928m3 methane gas could be captured to generate an average of 9,687,176 MW of electricity annually. This makes it a significant source of power supply to a city that suffers from incessant power outages. Analysis of composting organics in Lagos was also done using descriptive method. Although, it could be argued that composting is the most regenerative way of managing organics, but it has some problems associated with it. Earthcare Compost Company processes an average of 600 tons of organics on a daily basis. The fraction of waste processed is infinitesimal compared to the rate of waste generated. One major issue identified in this study as an obstacle to extensive use of this method is the marketability of compost. The study therefore suggests that government should focus on getting the best out of the

Family Background, Sexual Behaviour, and HIV/AIDS Vulnerability of Female Street Hawkers in Lagos Metropolis, Nigeria

ERIC Educational Resources Information Center

Oyefara, John Lekan

2005-01-01

This article examines the sexual behaviour and the HIV/AIDS knowledge and vulnerability of female street hawkers in Lagos metropolis, Nigeria. A total of 126 female street hawkers under 18 were sampled in a cross-sectional survey and six Focus Group Discussions (FGDs) were conducted to generate data from respondents. Data on sexual behaviour…

Preventive and social cost implications of Ebola Virus Disease (EVD) outbreak on selected organizations in Lagos state, Nigeria

PubMed Central

Olugasa, Babasola Oluseyi; Oshinowo, Oluwafunmilola Yemisi; Odigie, Eugene Amienwanlen

2015-01-01

Introduction As Ebola virus disease (EVD) continues to pose public health challenge in West Africa, with attending fears and socio-economic implications in the current epidemic challenges. It is compelling to estimate the social and preventive costs of EVD containment in a Nigerian city. Hence, this study was to determine the social and preventive cost implications of EVD among selected public institutions in Lagos, Nigeria, from July to December, 2014. Methods Questionnaires and key-informants interview were administered to respondents and administrators of selected hospitals, hotels and schools in Eti-Osa Local Government Area of Lagos State. Knowledge of disease transmission, mortality and protocols for prevention, including cost of specific preventive measures adopted against EVD were elicited from respondents. Descriptive statistics and categorical analysis were used to summarize and estimate social and preventive costs incurred by respective institutions. Results An estimated five million, nineteen thousand, three hundred and seventy-nine Naira and eighty kobo (N5,019,379.80) only was observed as direct and social cost implication of EVD prevention. This amount translated into a conservative estimate of one billion, twenty-seven million, ninety-four thousand, seven hundred and fifty-six Naira (N1,027,094,756.10) for a total of four thousand schools, two hundred and fifty-three hospitals and one thousand, four hundred and fifty one hotels in Lagos during the period (July 20-November 20, 2014). Conclusion The high cost of prevention of EVD within the short time-frame indicated high importance attached to a preventive policy against highly pathogenic zoonotic disease in Nigeria. PMID:26740848

Preparedness of government owned dental clinics for the management of medical emergencies: a survey of government dental clinics in Lagos.

PubMed

Gbotolorun, O M; Babatunde, L B; Osisanya, O; Omokhuale, E

2012-01-01

An emergency is a medical condition demanding immediate treatments. The aim of the study was to determine the knowledge and ability of dental surgeons in the management of medical emergencies and the availability of emergency drugs and equipment in government dental clinics and hospitals in Lagos State. The study was a descriptive cross-sectional study of knowledge and ability of Dental Surgeons in the management of medical emergencies, prevalence of medical emergencies in dental practice and availability of emergency drugs and equipment in dental practice in government dental clinics and hospitals in Lagos State. The study covered 22 government dental clinics and hospitals in Lagos State. Data obtained was entered into a computerand analyzed using Statistical Package for Social Science (SPSS) Version-16 data analysis software. Chi Square and cross-tabulations were used for the analysis. A 95% Confidence Level was used and a p-value of less than or equal to 0.05 was considered statistically significant. Of a population of 255 Dental Surgeons on the nominal rolls of all the health institutions, 224 (87%)responded.Of the total respondents, 204 (91.1%) stated they had no emergency kit in their dental clinics (p < 0.05) while 158 respondents (70.5%) stated they had no emergency drugs in their dental practice to manage medical emergencies (p < 0.05). The commonest emergencies reported was syncope 104 respondents (33.8%). 161 respondents (71.9%) claimed they are able to manage medical emergencies encountered in their dental practice if kits and drugs are available. The findings of the study show that government dental clinics/hospital in Lagos seem not to be adequately prepared to manage medical emergency. Although 71.9% of the dentist claimed they could mange such emergencies should they arise 91.1% and 70% of the respondent claimed they and no emergency kits and drugs to manage such emergencies in their hospital respectively should they arise.

Assessment of Day Caring Methods among Civil Servant Mothers of Reproductive Age in Lagos State Nigeria

ERIC Educational Resources Information Center

Akinnubi, Caroline Funmbi

2016-01-01

This study examined the day caring methods among the civil servants of reproductive age with children between three months to four years in Lagos State Nigeria. The research design employed for this study was a descriptive research design. A total number of 212 teachers and 128 ministry workers making a total of 340 reproductive age mothers were…

Desarrollo de un detector de rayos cósmicos de la colaboración LAGO en Buenos Aires - Aplicaciones en meteorología espacial

NASA Astrophysics Data System (ADS)

Coppola, M.; Bezzecchi, F.; Gulisano, A. M.; Masías-Meza, J. J.; Areso, O.; Ramelli, M.; Dasso, S.; LAGO Collaboration

2016-08-01

The study of low energy cosmic particles allows to analyze several aspects of major interest for space weather. Ground detectors permit to observe secundary particles produced during the cascades developed in the atmosphere. The characterization of a prototype for a water Cherenkov radiation particles detector, in the frame of the LAGO collaboration (Latin American Giant Observatory), is presented in this work. The collaboration plans to install this detector at the LAGO antarctic site. The developed acquisition system and the method used to make the energy callibration of the detector are detailed here, as also corrections for atmospheric effects.

Expanding Access for Training of Science Teachers through ODL: A Case Study of University of Lagos, Nigeria

ERIC Educational Resources Information Center

Okunuga, A. O.; Olaoluniyi, O.; Opara, A. I.

2013-01-01

Rising up to the challenge of shortage of middle manpower in Nigeria, the University of Lagos established the Correspondence and Open Studies Unit (COSU), now Distance Learning Institute DLI). Accounting, Business Administration and Science-Education were the pilot courses at the B.Sc. level. The Special Entry Preparatory Programme (SEPP) was…

Herbal medicines supplied by community pharmacies in Lagos, Nigeria: pharmacists’ knowledge

PubMed Central

Oshikoya, Kazeem Adeola; Oreagba, Ibrahim A.; Ogunleye, Olayinka O.; Oluwa, Rashidat; Senbanjo, Idowu O.; Olayemi, Sunday O.

Background The use of herbal medicines is on the increase globally and they are usually supplied in pharmacies as non-prescription medicines. Pharmacists are, therefore, responsible for educating and informing the consumers about rational use of herbal medicines. Objective To evaluate the knowledge of pharmacists in Lagos, Nigeria with regards to the herbal medicines they supplied by their pharmacies. Methods Pharmacists in charge of randomly selected 140 community pharmacies from 20 Local Government Areas in Lagos were required to fill out a self-administered questionnaire. We gathered information on their knowledge of the indications, adverse effects, potential drug-herb interactions and contraindications of the herbal medicines they supply in their pharmacies. Results Of the 140 questionnaires distributed, 103 (72.9%) participants completed the questionnaire appropriately. The majority (74; 71.8%) of the participants were males and 36-50 years (56; 54.4%). The pharmacies supplied mostly Yoyo cleanser bitters® (101; 98.5%), ginseng (97; 98.5%), Jobelyn® (91; 88.3%), Ciklavit® (68; 66.6%), gingko (66; 64.1%), herbal tea (66; 64.1%), and Aloe vera (57; 55.3%). The pharmacists self-rated their knowledge of herbal medicines mostly as fair (39%) and good (42%), but they exhibited poor knowledge with regards to the indications, contraindications and safety profiles. Seventy participants consulted reference materials such as leaflet insert in the herbal medicines (56%) and internet (20%) before supplying herbal medicines. The information most frequently sought was herb-drug interactions (85%), contraindications (75%) and adverse effects (70%). Conclusions Community pharmacists need to be informed about the indications and safety profiles of herbal medicines. PMID:24367462

Obstáculos a la adherencia y retención en los sistemas de salud público y privado según pacientes y personal de salud

PubMed Central

Arístegui, Inés; Dorigo, Analía; Bofill, Lina; Bordatto, Alejandra; Lucas, Mar; Cabanillas, Graciela Fernández; Sued, Omar; Cahn, Pedro; Cassetti, Isabel; Weiss, Stephen; Jones., Deborah

2016-01-01

Resumen Introducción el Programa Nacional de Sida garantiza el acceso universal a los antirretrovirales, aun así las personas que reciben medicamentos a través del sistema público no logran obtener una carga viral indetectable en la misma proporción que los pacientes del sistema privado. Este estudio cualitativo tiene como objeto identificar los factores asociados a la adherencia y retención en la cascada de atención de VIH de los sistemas de salud público y privado de Buenos Aires, según las percepciones de pacientes y del personal de salud. Métodos se registraron datos cualitativos de 12 entrevistas semi-estructuradas a informantes clave y 4 grupos focales de pacientes y personal de salud tanto del sistema público como privado. Se codificaron y analizaron temas predeterminados sobre adherencia, utilizando el software QRS Nvivo9® de análisis de datos cualitativos. Resultados pacientes y personal de salud de ambos sistemas coinciden en la importancia del estigma asociado al VIH, la relación médicopaciente, la comunicación entre ambos y la división de responsabilidades en relación al tratamiento como aspectos fundamentales para la adherencia y retención en la cascada de atención. Se observan diferencias entre los sistemas en la forma en que algunos de estos aspectos actúan. Las barreras estructurales se presentan como principales obstáculos del sistema público. Discusión se resalta la necesidad de intervenciones focalizadas en la díada médico-paciente que considere las particularidades de cada sistema de atención para facilitar el compromiso del paciente en la adherencia. PMID:26878024

Unmasking inequalities: Sub-national maternal and child mortality data from two urban slums in Lagos, Nigeria tells the story.

PubMed

Anastasi, Erin; Ekanem, Ekanem; Hill, Olivia; Adebayo Oluwakemi, Agnes; Abayomi, Oluwatosin; Bernasconi, Andrea

2017-01-01

Nigeria has one of the highest maternal mortality ratios in the world as well as high perinatal mortality. Unfortunately, the country does not have the resources to assess this critical indicator with the conventional health information system and measuring its progress toward the goal of ending preventable maternal deaths is almost impossible. Médecins Sans Frontières (MSF) conducted a cross-sectional study to assess maternal and perinatal mortality in Makoko Riverine and Badia East, two of the most vulnerable slums of Lagos. The study was a cross-sectional, community-based household survey. Nearly 4,000 households were surveyed. The sisterhood method was utilized to estimate maternal mortality and the preceding births technique was used to estimate newborn and child mortality. Questions regarding health seeking behavior were posed to female interviewees and self-reported data were collected. Data was collected from 3963 respondents for a total of 7018 sisters ever married. The maternal mortality ratio was calculated at 1,050/100,000 live births (95% CI: 894-1215), and the lifetime risk of maternal death at 1:18. The neonatal mortality rate was extracted from 1967 pregnancies reported and was estimated at 28.4/1,000; infant mortality at 43.8/1,000 and under-five mortality at 103/1,000. Living in Badia, giving birth at home and belonging to the Egun ethnic group were associated with higher perinatal mortality. Half of the last pregnancies were reportedly delivered in private health facilities. Proximity to home was the main influencing factor (32.4%) associated with delivery at the health facility. The maternal mortality ratio found in these urban slum populations within Lagos is extremely high, compared to the figure estimated for Lagos State of 545 per 100,000 live births. Urgent attention is required to address these neglected and vulnerable neighborhoods. Efforts should be invested in obtaining data from poor, marginalized, and hard-to-reach populations in

Strategies for Introducing New Curricula in West Africa. Final Report of the Seminar/Workshop (Lagos, Nigeria, November 12-16, 2001) (Strategies d'Adaptation des Nouveaux Curricula en Afrique de l'Ouest. Rapport Final du Seminaire/Atelier (Lagos, Nigeria, 12-16 Novembre 2001).

ERIC Educational Resources Information Center

Pillai, Sharmila, Ed.

The central theme of the Lagos, Nigeria, seminar/workshop was recognition for the teaching profession, particularly as being the most important educational change agent. Part 1, "Thematic Issues" includes: "Language Curriculum and Teaching in Multilingual Environments" (Sharmila Pillai); "The Situation in Nigeria" (E.…

Pattern of periodontal treatments performed at the periodontology clinic of the Lagos University Teaching Hospital: 22 months review.

PubMed

Umeizudike, K A; Ayanbadejo, P O; Savage, K O; Taiwo, O A

2012-01-01

A critical evaluation of the pattern of periodontal procedures performed is important in providing useful data to the administrator for proper planning and budgeting for dental health service. To assess the pattern of periodontal treatments performed over a given period of time at the Periodontology clinic of the Lagos University Teaching Hospital, Lagos, Nigeria. This was a twenty two months retrospective study of all periodontal procedures performed on patients seen at the periodontology clinic of the Lagos University Teaching Hospital between January 2006 and October 2007. The periodontology treatment record was used to retrieve information which included the patient's age, gender, diagnosis and periodontal procedures given. The procedures were further categorized into surgical and nonsurgical groups. The information obtained was then analyzed using Epi Info 2007 statistical software. A total of 1,938 patients were seen during this period. Females were 1009 (52.1%) and males were 929 (47.9%). (F/M, 1.1:1). A total of 2,110 periodontal treatments were performed. Majority of the patients received non-surgical periodontal therapy which constituted the bulk (96.3%) of the therapies. Scaling and polishing was the most frequently performed non-surgical procedure accounting for 1261 (62.1%) with slightly more males receiving the treatment. Of the surgical treatment modalities, operculectomy accounted for 65.4% and was carried out on more females than males. Regenerative procedures were the least performed surgical treatments. This study highlighted that non-surgical periodontal therapy, particularly scaling and polishing was the most frequently utilized periodontal procedure. Operculectomy was the predominant surgical procedure performed. The low percentage of regenerative surgical procedures was however below the desired expectation.

HIV association with conventional STDS (sexual transmitted diseases) in Lagos State, Nigeria.

PubMed

Otuonye, N M; Olukoya, D K; Odunukwe, N N; Idigbe, E O; Udeaja, M N; Bamidele, M; Onyewuchie, J I; Oparaugu, C T; Ayelari, O S; Oyekunle, B

2002-01-01

The study examined a possible association between HIV infection and conventional sexually transmitted diseases (STDS) in a population of 700 patients seen in some hospitals and clinics in Lagos State between November 1997 and December 1999. The patients were drawn mainly from LUTH and Jolad hospitals in Lagos State. In these hospitals, patients who presented with symptoms of STDS were screened clinically and microbiologically for agents of STDS and HIV antibodies. Screening was carried out using conventional methods. A total of 150 (21.5%) were found positive for various STDS while 550 (78.5%) were negative Also, 109 (15.8%) were sero-positive for HIV while 591 (84.4%) were sero-negative. The frequency of STDS diagnosed were, Treponema pallidum, 38(25.3%), Neisseria gonorrhoea 3(2.0%), Chlamydia trachomatis 26(17.3), Hepatitis B virus 60(40.0%) Staphylococcus aureaus, 20 (13.3%) and Candida albicans 3(2.0%). Data showed that Syphillis was the most prevalent STDS diagnosed while Calbicans and N. gonorrhoea are the least. Amongst the 150 (21.5%) patients positive with STDS, 82(54.65%) were found to be positive for HIV antibodies. The remaining 68(45.3%) patients were negative for HIV. The difference in sero-prevalence on the true group of patients rates was significant. The higher rate in the STDS patients strongly suggest some association between HIV infections andSTDS amongst the patients studied p = 0.05. It was also recorded that HIV-1 infection is four times more prevalent than HIV-2 in these patients.

Histopathological report of colorectal carcinoma resections: A 5-year audit in Lagos.

PubMed

Badmos, Kabir Bolarinwa; Rotimi, Olorunda; Lawal, Abdulrazzaq Oluwagbemiga; Osinowo, Adedapo O; Habeebu, Mohammed Y; Abdulkareem, Fatimah Biade

2018-01-01

Complete and accurate pathology reporting of colorectal carcinoma (CRC) resection specimen is critical to clinical management of individual patients. The study aims to audit colorectal cancer histopathology reporting in Lagos between 2011 and 2015 before the adoption of the Society for Gastroenterology and Hepatology in Nigeria pro forma in 2016. All resected CRC cases were identified from the Histopathology record of our Department and that of a private Laboratory in Lagos over a 5-year from 2011 to 2015. The dataset as contained in the pro forma was extracted from the reports and analysed using SPSS version 16 software. A total of 92 colorectal resections were received during the 5-year period consisting of 90 colonic and 2 rectal tumours. Data inclusiveness on tumour differentiation, extent of primary tumour, total lymph node and lymph node involvement were 96.7%, 91.3%, 83.7% and 92.4%, respectively. Tumour perforation, level of venous involvement and distant metastasis were reported in 73.9%, 21.7% and 96.7% respectively. The circumferential resection margin (CRM) in the 2 rectal tumours had 100% inclusiveness. Tumour node metastasis staging was complete in 87% of cases while Dukes staging was documented in 8.7% of the reports. None of the data items was 100% complete except the CRM for rectal carcinoma. Free text reporting results in incomplete data resulting in improper staging, especially the lymph node status. This highlights the need for pro forma reporting to ensure and maintain consistent reporting of important parameters required for proper staging and management of patients with colorectal cancer.

Home and School Environments as Determinant of Social Skills Deficit among Learners with Intellectual Disability in Lagos State

ERIC Educational Resources Information Center

Isawumi, Oyeyinka David; Oyundoyin, John Olusegun

2016-01-01

The study examined home and school environmental factors as determinant of social skills deficit among learners with intellectual disability in Lagos State, Nigeria. The study adopted survey research method using a sample size of fifty (50) pupils with intellectual disability who were purposively selected from five special primary schools in Lagos…

Private and Public Schooling in Low-Income Areas of Lagos State, Nigeria: A Census and Comparative Survey

ERIC Educational Resources Information Center

Tooley, James; Dixon, Pauline; Olaniyan, Olanrewaju

2005-01-01

A census and survey of schools in selected poor areas of Lagos State explored the nature and extent of private education, and compared inputs to public and private schooling. Of all schools (71%) were found to be private, with more unregistered private than government and registered private schools. It was estimated that 33% of school children…

Access or Quality? Why Do Families Living in Slums Choose Low-Cost Private Schools in Lagos, Nigeria?

ERIC Educational Resources Information Center

Härmä, Joanna

2013-01-01

Lagos is home to 12,098 private schools catering to 57% of the state's enrolled children, from ultra-rich to relatively poor households, with many schools targeting those of lower socio-economic status. Government schools were intended to provide a just and equitable option for all; however, they have not kept pace with demand in terms of both…

Private sector participation in domestic waste management in informal settlements in Lagos, Nigeria.

PubMed

Opoko, Akunnaya P; Oluwatayo, Adedapo A

2016-12-01

Lagos is one of the fastest growing cities in Africa, which is grappling with the challenges of poorly managed urbanisation. With an estimated population of about 17.5 million, solid waste management is one of the most pressing environmental challenges currently faced in the city. It is estimated that more than 9071847.4kg of urban waste is generated every day in the city. The city lacks the capacity to deal with such magnitude of waste. Consequently, the city has involved the private sector (private sector participation) in its waste management drive. This article examines the effectiveness of this public-private sector collaboration model in waste management in informal settlements in Lagos using empirical data. Major findings of the article include the irregularity of waste collection owing to a poor road network, an inadequate transport infrastructure and the desire to maximise profit, as well as poor waste handling and disposal methods by the private sector participation operators who are not chosen based on competence and capacity to perform. Another major finding is the lack of cooperation from residents evidenced in non-payment of bills and poor packaging of wastes, resulting in wastes being littered. The article concludes on the need to restructure the scheme through proper sensitisation of residents, selection of operators with demonstrable delivery capacity and provision of a well-maintained road network to facilitate access of operators to settlements. © The Author(s) 2016.

Mobile phones for retinopathy of prematurity screening in Lagos, Nigeria, sub-Saharan Africa.

PubMed

Oluleye, Tunji S; Rotimi-Samuel, Adekunle; Adenekan, Adetunji

2016-01-01

Retinopathy of prematurity (ROP), thought to be rare in Nigeria, sub-Saharan Africa, has been reported in recent studies. Developing cost-effective screening is crucial for detecting retinal changes amenable to treatment. This study describes the use of an iPhone combined with a 20-D lens in screening for ROP in Lagos, Nigeria. The ROP screening program was approved by the Lagos University Teaching Hospital Ethical Committee. Preterm infants with birthweight of less than 1.5 kg or gestational age of less than 32 weeks were screened. In conjunction with the neonatologist, topical tropicamide (0.5%) and phenylephrine (2.5%) was used to dilate the pupils. A pediatric lid speculum was used. Indirect ophthalmoscopy was used to examine the fundus to ensure there were no missed diagnoses. An iPhone 5 with 20-D lens was used to examine the fundus. The App Filmic Pro was launched in the video mode. The camera flash served as the source of illumination. Its intensity was controlled by the app. The 20-D lens was used to capture the image of the retina, which was picked up by the camera system of the mobile phone. Another app, Aviary, was used to edit the picture. The images captured by the system were satisfactory for staging and determining the need for treatment. An iPhone combined with a 20-D lens appear to be useful in screening for ROP in resource-poor settings. More studies are needed in this area.

Urban malaria treatment behaviour in the context of low levels of malaria transmission in Lagos, Nigeria.

PubMed

Brieger, W R; Sesay, H R; Adesina, H; Mosanya, M E; Ogunlade, P B; Ayodele, J O; Orisasona, S A

2001-01-01

Urban malaria in West Africa is not well documented. While rapid urbanisation may create environmental conditions that favour mosquito breeding, urban pollution may inhibit the growth of Anopheles species. In 1996, the Basic Support for Institutionalizing Child Survival (BASICS) Project of the U.S. Agency for International Development (USAID) started building urban community health coalitions in Lagos, Nigeria, to empower communities to provide prompt treatment and appropriate prevention for major causes of childhood morbidity and mortality, including malaria, diarrhoeal disease, acute respiratory infections and vaccine preventable diseases. Intervention against malaria was predicated on national policies that assumed Nigeria was holo-endemic for malaria and that prompt treatment of febrile illness with anti-malarial drugs was an appropriate action. At the suggestion and with the assistance of another USAID programme, the Environmental Health Project (EHP), BASICS embarked on a rapid assessment of the epidemiological, entomological and sociological situation of malaria transmission and case management in three Lagos communities. During April and May 1998, blood film investigation of 916 children between the ages of 6 months and 5 years yielded a parasite prevalence rate of 0.9%. Night knockdown collections of mosquitoes in rooms yielded only C. quinquefasciatus and A. aegypti. The same results were obtained for night landing collections on human bait. Very low densities of A. gambiae larvae were found in breeding sites in Lagos Island (0.7) and Ajegunle (0.3). In contrast, community members, during focus group discussion identified malaria, in it various culturally defined forms, as a major health problem. Among the children examined clinically, 186 (20.3%) reported an illness, which they called "malaria" in the previous two weeks, and 180 had sought treatment for this illness. Data obtained from 303 shops in the area documented that a minimum of US dollars 4

Patient refusal of glaucoma surgery and associated factors in Lagos, Nigeria.

PubMed

Adekoya, Bola Josephine; Akinsola, Feyisayo B; Balogun, Bola Grace; Balogun, Modupe Medinat; Ibidapo, Olajumoke O

2013-01-01

To determine the prevalence of patient refusal of glaucoma surgery (GSR) and the associated factors in Lagos, Nigeria. A multicenter cross-sectional survey was conducted in Lagos state, Nigeria. Twelve centres were invited to participate, but data collection was completed in 10. Newly diagnosed glaucoma patients were recruited and interviewed from these sites over a four week period on prior awareness of glaucoma, surgery refusal, and reason(s) for the refusal. Presenting visual acuity was recorded from the patient files. The odds ratio and 95% confidence intervals (CI) were calculated. A total of 208 newly diagnosed glaucoma patients were recruited. Sixty-five (31.2%) patients refused surgery. Fear of surgery (31 (47.7%) patients), and fear of going blind (19 (29.2%) patients) were the most common reasons. The odds ratio of surgery refusal were marital status - not married versus married (2.0; 95% CI, 1.02-3.94), use of traditional medication - users versus non users (2.4; 95% CI, 1.1-5.2), perception of glaucoma causing blindness - no versus yes (3.7; 95% CI, 1.3-10.5), type of institution - government versus private (5.7; 95% CI, 1.3-25.1), and visual acuity in the better eye - normal vision versus visual impairment (2.3; 95% CI, 1.1-4.9). Age, gender, level of education, family history of glaucoma, and prior awareness of the diagnosis of glaucoma, were not significantly associated with surgery refusal. Perception of patients concerning glaucoma blindness was the strongest factor on multivariate analysis. GSR was relatively low in this study. Unmarried status, use of traditional medications, perception that glaucoma cannot cause blindness, government hospital patients, and good vision in the better eye were associated with GSR. These factors might help in the clinical setting in identifying appropriate individuals for targeted counseling, as well as the need for increased public awareness about glaucoma.

Design of a residential microgrid in Lagos del Cacique, Bucaramanga, Colombia

NASA Astrophysics Data System (ADS)

Bellon, D.; González Estrada, O. A.; Martínez, A.

2017-12-01

In this paper is presented a model that analyses the options to provide energy to an interconnected house in Lagos del Cacique, Bucaramanga, Colombia. Three power supplies were considered: photovoltaic, 1 kW wind turbine, and a 2.6kW gasoline generator, as well as a battery for energy storage. The variables considered for the sensitivity analysis correspond to the price of gasoline and the variation in loads. The simulation results suggest an optimal configuration of microgrids in generator-photovoltaic panel-battery. Sensitivity variables were specified in order to evaluate the effect of uncertainty. The simulation was done through the Homer software and the results of the combinations of sources are suggestions of the same.

Technical quality of delivery care in private- and public-sector health facilities in Enugu and Lagos States, Nigeria.

PubMed

Hirose, Atsumi; Yisa, Ibrahim O; Aminu, Amina; Afolabi, Nathanael; Olasunmbo, Makinde; Oluka, George; Muhammad, Khalilu; Hussein, Julia

2018-06-01

Private-sector providers are increasingly being recognized as important contributors to the delivery of healthcare. Countries with high disease burdens and limited public-sector resources are considering using the private sector to achieve universal health coverage. However, evidence for the technical quality of private-sector care is lacking. This study assesses the technical quality of maternal healthcare during delivery in public- and private-sector facilities in resource-limited settings, from a systems and programmatic perspective. A summary index (the skilled attendance index, SAI), was used. Two-staged cluster sampling with stratification was used to select representative samples of case records in public- and private-sector facilities in Enugu and Lagos States, Nigeria. Information to assess criteria was extracted, and the SAI calculated. Linear regression models examined the relationship between SAI and the private and public sectors, controlling for confounders. The median SAI was 54.8% in Enugu and 85.7% in Lagos. The private for-profit sector's SAI was lower than and the private not-for-profit sector's SAI was higher than the public sector in Enugu [coefficient = -3.6 (P = 0.018) and 12.6 (P < 0.001), respectively]. In Lagos, the private for-profit sector's SAI was higher and the private not-for-profit sector's SAI was lower than the public sector [3.71 (P = 0.005) and -3.92 (P < 0.001)]. Results indicate that the technical quality of private for-profit providers' care was poorer than public providers where the public provision of care was weak, while private for-profit facilities provided better technical quality care than public facilities where the public sector was strong and there was a relatively strong regulatory body. Our findings raise important considerations relating to the quality of maternity care, the public-private mix and needs for regulation in global efforts to achieve universal healthcare.

Issues Surrounding HIV Status Disclosure: Experiences of Seropositive Women in Lagos, Nigeria

PubMed Central

Oseni, Oluwaseun E.; Okafor, Ifeoma P.; Sekoni, Adekemi O.

2017-01-01

Background: Disclosure of human immunodeficiency virus (HIV) seropositivity by infected women is crucial in HIV control. To determine the rates, patterns, effects, and determinants of disclosure of status among HIV-positive women in Lagos, Nigeria. Methods: This was a descriptive cross-sectional study. Simple random sampling method was used to select 364 HIV-positive women accessing care in HIV treatment centers in Lagos Island. Data were collected using interviewer-administered questionnaires and analyzed with Epi Info (version 3.5.3). Inferential statistics done was Chi-square test and level of statistical significance was set at <5%. Results: Mean age of respondents was 37.3 ± 3 years, and most were married or cohabiting in monogamous families. The disclosure rates were 81.9% to anyone (excluding a health care professional); 60.4% to spouse/sexual partners; and 67.7% disclosed on the same day of diagnosis. Main reasons for disclosure were failing health (49.3%) and a sense of responsibility to the spouse/sexual partner (33.6%). Major reasons for nondisclosure were negative public opinion (84.8%) and fear of losing relationships (40.3%). Positive reactions following disclosure were mostly acceptance: 75.2% (family member) and 72.3% (spouse/sexual partner) while blame was the main negative outcome. Longer duration of diagnosis significantly improved disclosure to anyone (P < 0.001). Older age (P < 0.001) and awareness of spouse/sexual partner's HIV status (P < 0.001) significantly improved disclosure to spouse/sexual partner. Conclusions: Many respondents had not disclosed their status and require support and counseling to do so. Community education regarding stigmatization should be intensified. PMID:28966749

Unmasking inequalities: Sub-national maternal and child mortality data from two urban slums in Lagos, Nigeria tells the story

PubMed Central

Adebayo Oluwakemi, Agnes; Abayomi, Oluwatosin

2017-01-01

Introduction Nigeria has one of the highest maternal mortality ratios in the world as well as high perinatal mortality. Unfortunately, the country does not have the resources to assess this critical indicator with the conventional health information system and measuring its progress toward the goal of ending preventable maternal deaths is almost impossible. Médecins Sans Frontières (MSF) conducted a cross-sectional study to assess maternal and perinatal mortality in Makoko Riverine and Badia East, two of the most vulnerable slums of Lagos. Materials and methods The study was a cross-sectional, community-based household survey. Nearly 4,000 households were surveyed. The sisterhood method was utilized to estimate maternal mortality and the preceding births technique was used to estimate newborn and child mortality. Questions regarding health seeking behavior were posed to female interviewees and self-reported data were collected. Results Data was collected from 3963 respondents for a total of 7018 sisters ever married. The maternal mortality ratio was calculated at 1,050/100,000 live births (95% CI: 894–1215), and the lifetime risk of maternal death at 1:18. The neonatal mortality rate was extracted from 1967 pregnancies reported and was estimated at 28.4/1,000; infant mortality at 43.8/1,000 and under-five mortality at 103/1,000. Living in Badia, giving birth at home and belonging to the Egun ethnic group were associated with higher perinatal mortality. Half of the last pregnancies were reportedly delivered in private health facilities. Proximity to home was the main influencing factor (32.4%) associated with delivery at the health facility. Discussion The maternal mortality ratio found in these urban slum populations within Lagos is extremely high, compared to the figure estimated for Lagos State of 545 per 100,000 live births. Urgent attention is required to address these neglected and vulnerable neighborhoods. Efforts should be invested in obtaining data from

A Bayesian Belief Network Approach to Explore Alternative Decisions for Sediment Control and water Storage Capacity at Lago Lucchetti, Puerto Rico

EPA Science Inventory

A Bayesian belief network (BBN) was developed to characterize the effects of sediment accumulation on the water storage capacity of Lago Lucchetti (located in southwest Puerto Rico) and to forecast the life expectancy (usefulness) of the reservoir under different management scena...

New Prof Omeje Pornography Addiction as Correlate of Psychosocial and Academic Adjustment of Students in Universities in Lagos State

ERIC Educational Resources Information Center

Ohuakanwa, Chijioke Ephraim; Omeje, Joachim Chinweike; Eskay, Michael

2012-01-01

The study sought to investigate the relationship between pornography addiction and psychosocial and academic adjustment of students in universities in Lagos State. In order to achieve this objective, five research questions were formulated and two hypotheses postulated. The subjects for the study consisted of 616 full-time third-year undergraduate…

Facilities available for biomedical science research in the public universities in Lagos, Nigeria.

PubMed

John, T A

2010-03-01

Across the world, basic medical scientists and physician scientists work on common platforms in state-of-the-arts laboratories doing translational research that occasionally results in bedside application. Biotechnology industries capitalise on useful findings for colossal profit.1 In Nigeria and the rest of Africa, biomedical science has not thrived and the contribution of publications to global high impact journals is low.2 This work investigated facilities available for modern biomedical research in Lagos public universities to extract culprit factors. The two public universities in Lagos, Nigeria were investigated by a cross sectional questionnaire survey of the technical staff manning biomedical science departments. They were asked about availability of 47 modern biomedical science research laboratory components such as cold room and microscopes and six research administration components such as director of research and grants administration. For convenient basic laboratory components such as autoclaves and balances, 50% responses indicated "well maintained and always functional" whereas for less convenient complex, high maintenance, state-of-the-arts equipment 19% responses indicated "well maintained and always functional." Respondents indicated that components of modern biomedical science research administration were 44% of expectation. The survey reveal a deficit in state-of the-arts research equipment and also a deficit in high maintenance, expensive equipment indicating that biomedical science in the investigated environment lacks the momentum of global trends and also lacks buoyant funding. In addition, administration supporting biomedical science is below expectation and may also account for the low contributions of research articles to global high impact journals.

Aspergilosis cervical con diseminación al sistema nervioso central. Presentación de un caso y revisión de bibliografía

PubMed Central

Vergara, Guillermo Enrique; Roura, Natalia; del Castillo, Marcelo; Mora, Andrea; Alcorta, Santiago Condomi; Mormandi, Rubén; Cervio, Andrés; Salvat, Jorge

2015-01-01

Introducción: la Aspergilosis Invasiva (AI) del Sistema Nervioso Central (SNC) es infrecuente y ocurre generalmente en pacientes inmunocomprometidos. Puede presentarse con cuadros de meningitis, aneurismas micóticos, infartos o abscesos. Es una infección con pronóstico reservado y puede afectar el SNC de forma primaria o secundaria a partir de un foco que se disemina por vía hematógena. Presentamos el caso de un paciente con AI con invasión primaria a nivel óseo y diseminación posterior al cerebro. Caso clínico: Paciente masculino de 25 años con diagnóstico de leucemia linfática aguda en tratamiento quimioterápico que presentó neumonitis por metotrexate por lo que inicia tratamiento con corticoides. Posteriormente agregó cervicalgia y con el diagnóstico de osteomielitis cervical se realiza punción bajo tomografía computada (TC) sin aislarse gérmenes. Se colocó Halo Vest e inició tratamiento antibiótico empírico. Posteriormente presentó afasia de expresión secundaria a lesión frontal izquierda. Se realizó evacuación de absceso cerebral aislando A. fumigatus. El tratamiento antibiótico específico posterior permitió una buena respuesta clínica y radiológica. Conclusión: La presencia de lesiones en el SNC de pacientes inmunocomprometidos debe incluir a las micosis como diagnóstico diferencial. La evacuación quirúrgica permite llegar rápidamente al diagnóstico mejorando la respuesta posterior al tratamiento antibiótico. Para evaluar la respuesta terapéutica y posibles recaídas se debe realizar un seguimiento periódico clínico radiológico. Palabras clave: Aspergilosis cerebral; Aspergilosis cervical; Aspergilosis invasiva; Voriconazol. PMID:26600985

Response of patent medicine vendors in rural areas of Lagos state Nigeria to antimalarial policy change.

PubMed

Oyeyemi, Abisoye; Ogunnowo, Babatunde; Odukoya, Oluwakemi

2015-06-01

Patent medicine vendors (PMVs) play an important role in the treatment of malaria, especially in the rural areas. Nigeria recently changed her antimalarial treatment policy from chloroquine to artemisinin-based combination therapy (ACT). To determine the response of PMVs to the new policy. A baseline study was conducted in two local government areas (LGAs) of Lagos state Nigeria as the first phase in an intervention study aimed at improving the malarial treatment practices of PMVs in rural Lagos. A mixed method design involving a questionnaire survey of 180 PMVs and four key informant interviews were used. An antimalarial drug (AMD) audit was also performed. More than 80% of respondents were aware of the policy change in malaria treatment, but only 23.9% sold an ACT for the last case of malaria treated in an under five child. The main determining factor of the particular AMD sold was PMV's personal choice (70.6%). About half (58.9%) of the shops stocked ACTs, the newly recommended antimalarials. The high awareness of the policy change did not translate to a commensurate increase in the sale of the new drugs. Factors beyond the PMVs need to be addressed for a successful adoption of the new policy.

Coliform and metal contamination in Lago de Colina, a recreational water body in Chihuahua State, Mexico.

PubMed

Rubio-Arias, Hector; Rey, Nora I; Quintana, Rey M; Nevarez, G Virginia; Palacios, Oskar

2011-06-01

Lago de Colina (Colina Lake) is located about 180 km south of the city of Chihuahua (Mexico), and during the Semana Santa (Holy Week) vacation period its recreational use is high. The objective of this study was to quantify coliform and heavy metal levels in this water body before and after the Holy Week vacation period in 2010. Twenty sampling points were randomly selected and two water samples were collected at each point near the surface (0.30 m) and at 1 m depth. After the Holy Week vacation the same twenty points were sampled at the same depths. Therefore, a total 80 water samples were analyzed for fecal and total coliforms and levels of the following metals: Al, As, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Si and Zn. It was hypothesized that domestic tourism contaminated this water body, and as a consequence, could have a negative impact on visitor health. An analysis of variance (ANOVA) study was performed for each element and its interactions considering a factorial design where factor A was sample date and factor B was sample depth. Fecal coliforms were only detected at eight sampling points in the first week, but after Holy Week, both fecal and total coliforms were detected at most sampling points. The concentrations of Al, B, Na, Ni and Se were only statistically different for factor A. The levels of Cr, Cu, K and Mg was different for both date and depth, but the dual factor interaction was not significant. The amount of Ca and Zn was statistically different due to date, depth and their interaction. No significant differences were found for any factor or the interaction for the elements As, Fe and Mn. Because of the consistent results, it is concluded that local tourism is contaminating the recreational area of Colina Lake, Chihuahua, Mexico.

Coliform and Metal Contamination in Lago de Colina, a Recreational Water Body in Chihuahua State, Mexico

PubMed Central

Rubio-Arias, Hector; Rey, Nora I.; Quintana, Rey M.; Nevarez, G. Virginia; Palacios, Oskar

2011-01-01

Lago de Colina (Colina Lake) is located about 180 km south of the city of Chihuahua (Mexico), and during the Semana Santa (Holy Week) vacation period its recreational use is high. The objective of this study was to quantify coliform and heavy metal levels in this water body before and after the Holy Week vacation period in 2010. Twenty sampling points were randomly selected and two water samples were collected at each point near the surface (0.30 m) and at 1 m depth. After the Holy Week vacation the same twenty points were sampled at the same depths. Therefore, a total 80 water samples were analyzed for fecal and total coliforms and levels of the following metals: Al, As, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Si and Zn. It was hypothesized that domestic tourism contaminated this water body, and as a consequence, could have a negative impact on visitor health. An analysis of variance (ANOVA) study was performed for each element and its interactions considering a factorial design where factor A was sample date and factor B was sample depth. Fecal coliforms were only detected at eight sampling points in the first week, but after Holy Week, both fecal and total coliforms were detected at most sampling points. The concentrations of Al, B, Na, Ni and Se were only statistically different for factor A. The levels of Cr, Cu, K and Mg was different for both date and depth, but the dual factor interaction was not significant. The amount of Ca and Zn was statistically different due to date, depth and their interaction. No significant differences were found for any factor or the interaction for the elements As, Fe and Mn. Because of the consistent results, it is concluded that local tourism is contaminating the recreational area of Colina Lake, Chihuahua, Mexico. PMID:21776236

Radio Engineering System of Short-Range Navigation. RSBN-2. Part I. (Radioteknicheskaya Sistema Blizhney Navigatsii RSBN-2)

DTIC Science & Technology

1977-02-09

RANGE NAVIGATION. RSBN-2 By: Ye. M. Yakovlev, A. N. Kleplkov, et al. English pages: 706 source: Radlotekhnlcheskaya Sistema Bllzhney Navigatsli...L4 and the grid of tube L5 (6N8S) limits grid m^^mammm^m^^^f.^^ rn .„ | -.,, ..S^JTv i tOC = 77050017 PAGE ^ I current©. |: *■ «a—m

The Relevance of Multi Media Skills in Teaching and Learning of Scientific Concepts in Secondary Schools in Lagos State, Nigeria

ERIC Educational Resources Information Center

Okedeyi, Abiodun S.; Oginni, Aderonke M.; Adegorite, Solomon O.; Saibu, Sakibu O.

2015-01-01

This study investigated the relevance of multi media skills in teaching and learning of scientific concepts in secondary schools. Self constructed questionnaire was administered to 120 students randomly selected in four secondary schools in Ojo Local Government Area of Lagos state. Data generated were analyzed using chi-square statistical…

Fractionation and ecotoxicological implication of potentially toxic metals in sediments of three urban rivers and the Lagos Lagoon, Nigeria, West Africa.

PubMed

Oyeyiola, Aderonke O; Davidson, Christine M; Olayinka, Kehinde O; Alo, Babajide I

2014-11-01

The potential environmental impact of sediment-bound Cd, Cr, Cu, Pb and Zn in three trans-urban rivers in Lagos state and in the Lagos Lagoon was assessed by use of the modified Community Bureau of Reference (BCR) sequential extraction. The quality of the data was checked using BCR CRM 143R and BCR CRM 701. Good agreement was obtained between found and certified/indicative values. Of the rivers, the Odo-Iyaalaro, was generally the most contaminated and the Ibeshe the least. Higher concentrations of metals were generally found in the dry season compared to the wet season. Cadmium and Zn were released mostly in the acid exchangeable step of the sequential extraction, indicating that they have the greatest potential mobility and bioavailability of the analytes studied. Chromium and Cu were associated mainly with the reducible and oxidisable fractions, and Pb predominantly with the reducible and residual fractions. Sediments with the highest pseudototal analyte concentrations also released higher proportions of analytes earlier in the sequential extraction procedure. The study suggests that, during the dry season, potentially toxic metals (PTM) may accumulate in sediments in relatively labile forms that are released and can potentially be transported or bioaccumulate in the rainy season. Application of risk assessment codes and Hankanson potential risk indices indicated that Cd was the element of greatest concern in the Lagos Lagoon system. The study indicated that there is a need to strengthen environmental management and pollution control measures to reduce risk from PTM, but that even relatively simple strategies, such as seasonal restrictions on dredging and fishing, could be beneficial.

Ambulance services of lagos state, Nigeria: a six-year (2001-2006) audit.

PubMed

Adewole, O A; Fadeyibi, I O; Kayode, M O; Giwa, S O; Shoga, M O; Adejumo, A O; Ademiluyi, S A

2012-01-01

Emergency medical care is designed to overcome the factors most commonly implicated in preventable mortality, such as delays in seeking care, access to health facility, and the provision of adequate care at the facility. The developed world has recognized the importance of organized emergency medical services and has well established systems. The Lagos State Government established the first emergency medical system in Nigeria in 2001. This was to review the activities of the Lagos State Emergency Ambulance Services (LASAMBUS) within the stated period with the hope that our findings can be used to audit the system and make recommendations for further improvement. We reviewed the records of the State Ministry of Health for the data on the activities of LASAMBUS from 2001-2006. The number and types of emergencies that were seen and managed with the associated morbidity and mortality were reviewed. The constraints that were encountered by the LASAMBUS staff were also studied. The data that was obtained was entered into a proforma designed for the study. Analysis of the data was done using the Microsoft Excel software. A total of 32,774 cases comprising 21,977(67.1%) males,10,797(32.9%) females and a male to female (M:F) ratio of 2.04:1, were seen during the study period. Trauma was responsible for 29,500 (90%) of the cases. No mortality was recorded during the transfer of the cases. The records of mortality for the LASAMBUS-transferred cases were not available. Trauma cases formed the majority of the cases that were seen with road traffic accident constituting a large proportion of these. Health education focusing on improving driving etiquette of Drivers and injury prevention should intensified. More equipped emergency centres should be established to reduce victims transit and injuryintervention time. Record keeping and documentations should be improved for better assessment of the activities.

Comparing the knowledge, attitude and practices of health care workers in public and private primary care facilities in Lagos State on Ebola virus disease.

PubMed

Idris, Bilqisu Jibril; Inem, Victor; Balogun, Mobolanle

2015-01-01

The West African sub-region is currently witnessing an outbreak of EVD that began in December 2013. The first case in Nigeria was diagnosed in Lagos, at a private medical facility in July 2014. Health care workers are known amplifiers of the disease. The study aimed to determine and compare EVD knowledge, attitude and practices among HCWs in public and private primary care facilities in Lagos, Nigeria. This was a comparative cross-sectional study. Seventeen public and private primary care facilities were selected from the 3 senatorial districts that make up Lagos State. 388 respondents from these facilities were selected at random and interviewed using a structured questionnaire. Proportion of respondents with good knowledge and practice among public HCWs was 98.5% and 93.8%; and among private HCW, 95.9% and 89.7%. Proportion of respondents with positive attitude was 67% (public) and 72.7% (private). Overall, there were no statistically significant differences between the knowledge, attitude and preventive practices of public HCWs and that of private HCWs, (p≤0.05). Timely and intense social mobilization and awareness campaigns are the best tools to educate all segments of the community about public health emergencies. There exists significant surmountable gaps in EVD knowledge, negative attitude and sub-standard preventive practices that can be eliminated through continued training of HCW and provision of adequate material resources.

Comparing the knowledge, attitude and practices of health care workers in public and private primary care facilities in Lagos State on Ebola virus disease

PubMed Central

Idris, Bilqisu Jibril; Inem, Victor; Balogun, Mobolanle

2015-01-01

Introduction The West African sub-region is currently witnessing an outbreak of EVD that began in December 2013. The first case in Nigeria was diagnosed in Lagos, at a private medical facility in July 2014. Health care workers are known amplifiers of the disease. The study aimed to determine and compare EVD knowledge, attitude and practices among HCWs in public and private primary care facilities in Lagos, Nigeria. Methods This was a comparative cross-sectional study. Seventeen public and private primary care facilities were selected from the 3 senatorial districts that make up Lagos State. 388 respondents from these facilities were selected at random and interviewed using a structured questionnaire. Results Proportion of respondents with good knowledge and practice among public HCWs was 98.5% and 93.8%; and among private HCW, 95.9% and 89.7%. Proportion of respondents with positive attitude was 67% (public) and 72.7% (private). Overall, there were no statistically significant differences between the knowledge, attitude and preventive practices of public HCWs and that of private HCWs, (p≤0.05). Conclusion Timely and intense social mobilization and awareness campaigns are the best tools to educate all segments of the community about public health emergencies. There exists significant surmountable gaps in EVD knowledge, negative attitude and sub-standard preventive practices that can be eliminated through continued training of HCW and provision of adequate material resources. PMID:26740847

Precious metal-bearing epithermal deposits in western Patagonia (NE Lago Fontana region), Argentina

NASA Astrophysics Data System (ADS)

Lanfranchini, Mabel Elena; Etcheverry, Ricardo Oscar; de Barrio, Raúl Ernesto; Recio Hernández, Clemente

2013-04-01

Precious metal-bearing quartz veins occur at the northeastern sector of the Lago Fontana region in southwestern Argentina, within the context of the Andean continental magmatic arc environment. The deposits and their associated alteration zones are spatially related to a Cretaceous calc-alkaline magmatism represented by silicic dikes and hypabyssal intrusions, and hosted by a Late Jurassic to Cretaceous volcano-sedimentary sequence. The veins and related veinlets crop out discontinuously, in general terms in a NW-SE belt. The primary vein mineral assemblage is composed mostly of pyrite ± galena ± chalcopyrite > hematite ± arsenopyrite in silica gangue minerals. Chemical analyses of grab samples from selected quartz veins show as much as 5.7 ppm Au and 224 ppm Ag, as well as elevated Pb, Cu, and Zn. Hydrothermal fluids caused an innermost silicification and adularia-sericite alteration assemblage, and an external propylitic halo. Sulfur isotope values measured for sulfides (δSS from -1.90 to +1.56‰), and oxygen and hydrogen isotopes measured on quartz crystals and extracted primary fluid inclusion waters (δOO = -2.85 to +5.40‰; δDO = -106.0 to -103.4‰) indicate that mineralization probably formed from magmatic fluids, which were mixed with meteoric waters. Also, fluid inclusion data from quartz veins point out that these fluids had low salinity (1.7-4.2 wt% NaCl equiv.), and temperatures of homogenization between 180 and 325 °C. Mineralogical, petrographic and geochemical features for mineralized surface exposures indicate a typical adularia-sericite, low sulfidation epithermal system in the Lago Fontana area that represents a promising target for further exploration programs.

Contraception among bankers in an urban community in Lagos State, Nigeria.

PubMed

Meka, Ijeoma Angela; Okwara, Emmanuel Chidiebere; Meka, Anthony Obiamaka

2013-01-01

Contraception means procedures employed to interfere at one stage or the other with the normal sequence of events in the process of reproduction leading to a failure in conception. It means voluntary techniques adopted to achieve birth control. Its use remains sensitive worldwide. Within the same society, contraception varies amongst people of different socio-cultural, educational, religious, or occupational affiliations. It also varies between urban and rural settlements. Some contraceptive techniques also prevent sexually transmitted infections (STIs). The prevalence of STIs also varies with these same factors. There is very limited literature on contraception exclusively amongst bankers. We sought to investigate the level of awareness and practice of contraception amongst bankers in an urban society in Lagos State, Nigeria. In this descriptive cross-sectional study, 200 self-administered structured questionnaires were retrieved from bankers from 5 banks selected by simple random sampling in Surulere Local Government Area of Lagos State, Nigeria. Data was subsequently statistically analyzed using SPSS. The age range was 21-45 years, mean 28.8±1.4 years, 51.7% were males (72% single, 27% married, 1% separated) and 48.3% were females (52.4% single, 47.6% married). All (100%) respondents were aware of contraception, 93.3% males and 91.7% females were sexually active, 88.9% males and 84.5% females believe contraception is useful. Most (71.4%) respondents practice contraception, males (81%) being more than females (61.1%), p < 0.05. More (71.4%) females and fewer (37.8%) males believe that contraception prevents pregnancy but not STIs, 28.6% of females and 46.6% of males believe it prevents both pregnancy and STIs, whereas 14% of males and no female believe contraception prevents STIs but not pregnancy. The awareness of and practice of contraception was very high among the bankers but more male bankers practice contraception whereas more female bankers perceive

High prevalence of HIV, chlamydia and gonorrhoea among men who have sex with men and transgender women attending trusted community centres in Abuja and Lagos, Nigeria.

PubMed

Keshinro, Babajide; Crowell, Trevor A; Nowak, Rebecca G; Adebajo, Sylvia; Peel, Sheila; Gaydos, Charlotte A; Rodriguez-Hart, Cristina; Baral, Stefan D; Walsh, Melissa J; Njoku, Ogbonnaya S; Odeyemi, Sunday; Ngo-Ndomb, Teclaire; Blattner, William A; Robb, Merlin L; Charurat, Manhattan E; Ake, Julie

2016-01-01

Sexually transmitted infection (STI) and HIV prevalence have been reported to be higher amongst men who have sex with men (MSM) in Nigeria than in the general population. The objective of this study was to characterize the prevalence of HIV, chlamydia and gonorrhoea in this population using laboratory-based universal testing. TRUST/RV368 represents a cohort of MSM and transgender women (TGW) recruited at trusted community centres in Abuja and Lagos, Nigeria, using respondent-driven sampling (RDS). Participants undergo a structured comprehensive assessment of HIV-related risks and screening for anorectal and urogenital Chlamydia trachomatis and Neisseria gonorrhoeae , and HIV. Crude and RDS-weighted prevalence estimates with 95% confidence intervals (CIs) were calculated. Log-binomial regression was used to explore factors associated with prevalent HIV infection and STIs. From March 2013 to January 2016, 862 MSM and TGW (316 in Lagos and 546 in Abuja) underwent screening for HIV, chlamydia and gonorrhoea at study enrolment. Participants' median age was 24 years [interquartile range (IQR) 21-27]. One-third (34.2%) were identified as gay/homosexual and 65.2% as bisexual. The overall prevalence of HIV was 54.9%. After adjusting for the RDS recruitment method, HIV prevalence in Abuja was 43.5% (95% CI 37.3-49.6%) and in Lagos was 65.6% (95% CI 54.7-76.5%). The RDS-weighted prevalence of chlamydia was 17.0% (95% CI 11.8-22.3%) in Abuja and 18.3% (95% CI 11.1-25.4%) in Lagos. Chlamydia infection was detected only at the anorectal site in 70.2% of cases. The RDS-weighted prevalence of gonorrhoea was 19.1% (95% CI 14.6-23.5%) in Abuja and 25.8% (95% CI 17.1-34.6%) in Lagos. Overall, 84.2% of gonorrhoea cases presented with anorectal infection only. Over 95% of STI cases were asymptomatic. In a multivariable model, increased risk for chlamydia/gonorrhoea was associated with younger age, gay/homosexual sexual orientation and higher number of partners for receptive anal sex

Detection of toxigenic Clostridium perfringens and Clostridium botulinum from food sold in Lagos, Nigeria.

PubMed

Chukwu, Emelda E; Nwaokorie, Francisca O; Coker, Akitoye O; Avila-Campos, Mario J; Solis, Rosa L; Llanco, Luis A; Ogunsola, Folasade T

2016-12-01

Food-borne diseases contribute to the huge burden of sickness and death globally and in the last decade, have become more frequently reported in Africa. In line with this, food safety is becoming a significant and growing public health problem in Nigeria. Diarrhoea is a common problem in Nigeria and has been reported but there has been little data on the possibility of clostridia as aetiological agents. Clostridium species are ubiquitous in the environment and in the gastrointestinal tract of man and animals and can serve as a marker for faecal contamination. We set out to determine the potential of these foods to transmit Clostridium species. A total of 220 food commodities from six local governments in Lagos State were sampled. Isolates obtained were identified based on cultural, morphological and biochemical characteristics. Toxinotyping was done using multiplex-PCR with primers specific for alpha, beta, epsilon and iota-toxin genes, enterotoxigenic cpe gene and neurotoxigenic BoNt gene. Fifty (22.7%) clostridial species were isolated of which 29 (58%) were identified as C. perfringens. Toxinotyping of the 29 strains showed that 28 (96.6%) were toxin producing C. perfringens type A while one (3.4%) was C. perfringens type D. Two (4%) C. botulinum species were isolated and identified by 16S rRNA sequencing, both harbouring BoNt/A gene. The contamination rates of food with Clostridium species show that food hygiene is a problem and Clostridium species may be a source of food borne disease in Lagos State, Nigeria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evidences of "Lago-Mare" episode around the Messinian-Pliocene boundary in eastern Tunisia (central Mediterranean)

NASA Astrophysics Data System (ADS)

Frigui, Mouna; Ben Youssef, Mohamed; Ouaja, Mohamed

2016-11-01

Eight stratigraphic sections, located in northeastern part of the Sahel area of Tunisia recorded evidences of "Lago-Mare" episode and events related to the Messinian-Late Pliocene interval. A comparison with previous studies carried on sections from neighboring areas and boreholes data drilled within the Gulf of Hammamet and the Gulf of Gabès, is conducted and gives useful information to characterize the Late Messinian to Late Pliocene events. The most notable feature distinguished in the studied area consists on the lack of gypsum, commonly recorded in relation with the crucial event of the Messinian Salinity Crisis. However, only lagoonal deposits, bearing messinian brackish fauna, are encountered. These sediments are usually attributed to the "Segui" formation or the so called "Mio-Pliocene continental". Thin sections samples and field observations have recognized sands, marls, clays, lacustrine limestone, some gypsum lenses, mud-cracks, lignite and Messinian brackish fauna. Similar deposits were previously described in the Kechabta basin from the Northern Tunisia and in some wells from the Gulf of Gabès and the Gulf of Hammamet. We suggest that all these facies belong to the coeval of the "Lago-Mare" facies within Eastern and Western Mediterranean basins (e.g. Sicily, Mallorca, Libya and Cyprus). Finally, four major erosional surfaces have been recorded within the Late Messinian-Late Pliocene deposits, aged post-Tortonian, intra-Messinian, Late Messinian and intra-Pliocene times. They seem to be the result of local tectonic uplifts and eustatic fluctuations.

Estimating urban trees and carbon stock potentials for mitigating climate change in Lagos: Case of Ikeja Government Reserved Area (GRA)

NASA Astrophysics Data System (ADS)

Elias, P. O.; Faderin, A.

2014-12-01

Urban trees are a component of the urban infrastructure which offers diverse services including environmental, aesthetic and economic. The accumulation of carbon in the atmosphere resulting from the indiscriminate distribution of human populations and urban activities with the unsustainable consumption of natural resources contributes to global environmental change especially in coastal cities like Lagos. Carbon stocks and sequestration by urban trees are increasingly recognized to play significant roles for mitigating climate change. This paper focuses on the estimation of carbon stock and sequestration through biomass estimation and quantification in Ikeja GRA, Lagos. Ikeja possesses a characteristic feature as a microcosm of Lagos due to the wide range of land uses. A canopy assessment of tree population was carried out using itree canopy software. A GPS survey was used to collect an inventory of all trees showing their location, spatial distribution and other attributes. The analysis of the carbon storage and sequestration potential of both actual and potential tree planting sites involved biomass estimations from tree allometry equations. Trees were identified at species level and measurements of their dendrometric values were recorded and integrated into the GIS database to estimate biomass of trees and carbon storage. The trees in the study area were estimated to have a biomass of 441.9 mg and carbon storage of 221.395 kg/tree. By considering the potential tree planting sites the estimated carbon stored increased to 11,352.73 kg. Carbon sequestration value in the study area was found to be 1.6790 tonnes for the existing trees and 40.707 tonnes for the potential tree planting sites (PTPS). The estimation of carbon storage and sequestration values of trees are important incentives for carbon accounting/footprints and monitoring of climate change mitigation which has implications for evaluation and monitoring of urban ecosystem.

Workability of Safety Education and Training for Workers' Strategy in Accident Reduction in Selected Manufacturing Industries in Lagos State

ERIC Educational Resources Information Center

Ayodele, Rachael B.; Olubayo-Fatiregun, Martina A.

2013-01-01

This study determined the workability of Safety Education and Training for Workers' strategy in reducing accidents. A descriptive survey research design was used. A total of 20 Managerial staff with mean work experience of 13.5 years was selected from 10 manufacturing industries in Lagos State, using intact group method. They were 100% males. Data…

Knowledge and use of dietary supplements by students of College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria

PubMed Central

Aina, Bolajoko A.; Ojedokun, Oluwayemisi A.

2014-01-01

Rationale: Nutritional supplements are preparations intended to supplement the diet and provide nutrients. They include vitamins, minerals, fiber, fatty acids, or amino acids, that may be missing or may not be consumed in sufficient quantities in a person's diet. Many health professionals including dietitians, physicians and pharmacists are supplement users. Objectives: The objectives of the present study were to determine knowledge and use of dietary supplements among students of College of Medicine, University of Lagos who are potential health professionals. Methodology: A self-administered questionnaire with a mix of open and close ended questions was employed to collect data in this study. It was distributed to 300 students that were in their final year in various departments of the college. Findings: Response rate was 89%. About 86% of the students have used dietary supplement before while half of them (50%) have used it in the past 12 months. The common types of dietary supplements used in the past 12 months are the vitamins. The reasons for use by the students were good health, poor diet, to boost immunity, weight gain and doctor's prescription. Most of the students were occasional and once in a while users. Conclusions: Majority of the students were aware of dietary supplement use and most of them were occasional users. PMID:25031497

Yield per recruit of the peacock bass Cichla monoculus (Spix and Agassiz, 1831) caught in Lago Grande at Manacapuru (Amazonas - Brazil).

PubMed

Campos, C P; Freitas, C E C

2014-02-01

We evaluated the stock of peacock bass Cichla monoculus caught by a small-scale fishing fleet in Lago Grande at Manacapuru. The database was constructed by monthly samplings of 200 fish between February 2007 and January 2008. We measured the total length (cm) and total weight (gr) of each fish. We employed previously estimated growth parameters to run a yield per recruit model and analyse scenarios changing the values of the age of the first catch (Tc), natural mortality (M), and fishing mortality (F). Our model indicated an occurrence of overfishing because the fishing effort applied to catch peacock in Lago Grande at Manacapuru is greater than that associated with the maximum sustainable yield. In addition, the actual size of the first catch is almost half of the estimated value. Although there are difficulties in enforcing a minimum size of the catch, our results show that an increase in the size of the first catch to at least 25 cm would be a good strategy for management of this fishery.

High prevalence of HIV, chlamydia and gonorrhoea among men who have sex with men and transgender women attending trusted community centres in Abuja and Lagos, Nigeria

PubMed Central

Keshinro, Babajide; Crowell, Trevor A; Nowak, Rebecca G; Adebajo, Sylvia; Peel, Sheila; Gaydos, Charlotte A; Rodriguez-Hart, Cristina; Baral, Stefan D; Walsh, Melissa J; Njoku, Ogbonnaya S; Odeyemi, Sunday; Ngo-Ndomb, Teclaire; Blattner, William A; Robb, Merlin L; Charurat, Manhattan E; Ake, Julie

2016-01-01

Introduction Sexually transmitted infection (STI) and HIV prevalence have been reported to be higher amongst men who have sex with men (MSM) in Nigeria than in the general population. The objective of this study was to characterize the prevalence of HIV, chlamydia and gonorrhoea in this population using laboratory-based universal testing. Methods TRUST/RV368 represents a cohort of MSM and transgender women (TGW) recruited at trusted community centres in Abuja and Lagos, Nigeria, using respondent-driven sampling (RDS). Participants undergo a structured comprehensive assessment of HIV-related risks and screening for anorectal and urogenital Chlamydia trachomatis and Neisseria gonorrhoeae, and HIV. Crude and RDS-weighted prevalence estimates with 95% confidence intervals (CIs) were calculated. Log-binomial regression was used to explore factors associated with prevalent HIV infection and STIs. Results From March 2013 to January 2016, 862 MSM and TGW (316 in Lagos and 546 in Abuja) underwent screening for HIV, chlamydia and gonorrhoea at study enrolment. Participants’ median age was 24 years [interquartile range (IQR) 21–27]. One-third (34.2%) were identified as gay/homosexual and 65.2% as bisexual. The overall prevalence of HIV was 54.9%. After adjusting for the RDS recruitment method, HIV prevalence in Abuja was 43.5% (95% CI 37.3–49.6%) and in Lagos was 65.6% (95% CI 54.7–76.5%). The RDS-weighted prevalence of chlamydia was 17.0% (95% CI 11.8–22.3%) in Abuja and 18.3% (95% CI 11.1–25.4%) in Lagos. Chlamydia infection was detected only at the anorectal site in 70.2% of cases. The RDS-weighted prevalence of gonorrhoea was 19.1% (95% CI 14.6–23.5%) in Abuja and 25.8% (95% CI 17.1–34.6%) in Lagos. Overall, 84.2% of gonorrhoea cases presented with anorectal infection only. Over 95% of STI cases were asymptomatic. In a multivariable model, increased risk for chlamydia/gonorrhoea was associated with younger age, gay/homosexual sexual orientation and higher

Cost implication of irrational prescribing of chloroquine in Lagos State general hospitals.

PubMed

Aina, Bolajoko A; Tayo, Fola; Taylor, Ogori

2008-02-01

A major share of the hospital budget is spent on drugs. Irrational use of these drugs is a waste of financial and human resources that could have been deployed for another use within the hospital setting especially in cases where such drugs are provided free to patients. Also there is increased morbidity and progression of severity with irrational use. The objective of this study was to determine the irrational use of chloroquine and the subsequent cost implications in Lagos State general hospitals. A retrospective study period of one year (January to December, 2000) was selected. A total of 18,781 prescription forms of "Free Eko Malaria" were sampled for children and adults from all the Lagos State general hospitals. Drug costs in each prescription form were identified. Cost effectiveness analysis of chloroquine tablet and intramuscular injection was undertaken. The average cost of medicine per prescription was 132.071 ($1.03) which should have been 94.22 ($0.73) if prescribed rationally. The total cost of prescriptions for malaria under study was 2,480,425.00 ($19,348.09). About 68% {(1,679,444.00) ($13,100.19)} of the total cost was lost to irrational prescribing. This is a waste of scarce resources. When the prescriptions were differentiated into the different dosage forms prescribed, the prescriptions containing intramuscular injections only had over 90% of the cost lost to irrational prescribing. Cost effectiveness analysis showed that chloroquine tablet was 17 times more cost effective than chloroquine injection (intramuscular) from a health care system perspective while it was 14 times more cost effective from a patient perspective. There is waste of scarce resources with irrational dispensing of drugs and these resources could have been deployed to other uses or areas within the hospitals. The tablet chloroquine was more cost effective than injection chloroquine (intramuscular). Increasing the cost of tablets, decreasing effectiveness of tablets

Ocular findings in acquired immunodeficiency syndrome patients in Lagos, Nigeria.

PubMed

Onakoya, A O; Odeyemi, M G; Aribaba, O T; Akinsola, F B

2012-01-01

There is paucity of studies on the prevalence and pattern of ocular complication in HIV patients in developing countries where 90% of all HIV sufferers live. Most studies were carried out in industrialized countries and are not representative of the spectrum of ocular complication of HIV and it's prevalence in developing countries. To determine the prevalence of ocular disorders in adult (> 15 years ) AIDS patients at PEPFAR clinic in Lagos, Nigeria. All consecutive adult Seropositive HIV/AIDS patients of PEPFAR Clinic at the Lagos University Teaching Hospital between February 1st-March 15th 2008 were enrolled into the study Cross sectional and non randomized, convenient study was used. Biodata and medical history were recorded on interviewer administered questionnaire. Participants were examined according to standard protocol comprising visual acuity, intraocular pressure, anterior segment examination with slit lamp biomicroscopy, dilated fundoscopy and fundus photograph where necessary. PCV, CD4+ count, viral load at diagnosis, stage of HIV disease were extracted from patients' records. Details of drug were regimen also recorded. Data analysis was performed with EPI-lnfo 6.04 version; Chi square and student t test used to describe statistical association. A total of 400 patients were studied. Male:female ratio was 1.7 and mean age was 40 years (S.D. + 9.12). Ocular disorders seen in 78.5% of patients; HIV related ocular disorders occurred in 45 (11.3) patients. Conjunctival microvasculopathy 166 patients (41.5%), pingueculum in 114 (28.5%), pterygium in 76 (19.0%), refractive error in 93 (23.3%), cataract in 12 (3.0%), and 22 (5.5%) Glaucoma suspects. HIV retinopathy and allergic eye disease in one patient each (0.3%). Presumed Cytomegalovirus retinitis 7 (1.8%), 14 (3.5%) Toxoplasmosis, 8 (2.0%) HZO, and 15 (3.8%) Presumed Squamous cell carcinoma. Eighty six (21.5%) of the patients had no abnormality. 91.4% of eyes examined had visual acuity with best correction

Clinicopathologic review of polyps biopsied at colonoscopy in Lagos, Nigeria.

PubMed

Oluyemi, Aderemi; Awolola, Nicholas; Oyedeji, Olufemi

2016-01-01

Colorectal polyps are known precursors of colorectal cancers. The increase in utilization of colonoscopy in Nigeria has meant a rise in the recently reported incidence of these lesions. The aim of this study is to evaluate the clinicopathological profile of colorectal polyps biopsied during the inaugural 12 month period of colonoscopy from a private endoscopy suite in Nigeria. This is a retrospective review of all the clients who had polyps diagnosed at colonoscopy over a 12 month period (August 2014 -July 2015) at a private endoscopy suite in Lagos, Nigeria. This analysis of prospectively collected data was performed using clinical information from the endoscopy logs and pathology database system of a private endoscopy suite based in Lagos, Nigeria. A total of 125 colonoscopies were carried out over the stated period. Of these, 14 individuals had a total of 18 polyps- 4 clients (28.6% of the persons with polyps) had two polyps each. The polyp detection rate was 11.2% while the polyp per colonoscopy rate was 14.4%. Of these clients, males were 10 in number; giving a male to female ratio of 2.5:1. Their ages ranged from 37 to 77 years (mean= 57.3 years). The presenting complaint at colonoscopy was hematochezia in 11 (78.6%), new onset constipation in 2 (14.2%) and peri-anal pain in 1 patient (7.1%). The polyps were distributed as follows; 2 (11.1%) in the ascending colon, 1 (5.6%) each in the transverse and descending colons, 8 (44.4%) in the sigmoid colon, 6(33.3%) located in the rectum. Hence, there was left sided (15 of 18= 83.3%) preponderance. Pathologically, tubular (adenomatous) polyp with or without low grade dysplastic changes was diagnosed in 6 of the 18 polyps (giving an adenoma detection rate of 4.8%), 4 (22.2%) were inflammatory polyps, 1 (5.6%) was malignant and another had the rare inflammatory fibroid polyp. Five (27.8%) of the specimens were reported as non-specific colitis. The study supports the present wisdom that polyps are clearly less

Rock magnetic and geochemical proxies for iron mineral diagenesis in a tropical lake: Lago Verde, Los Tuxtlas, East Central Mexico

NASA Astrophysics Data System (ADS)

Ortega, Beatriz; Caballero, Margarita; Lozano, Socorro; Vilaclara, Gloria; Rodríguez, Alejandro

2006-10-01

Magnetic and non-magnetic mineral analyses were conducted on a lacustrine sequence from Lago Verde in the tropical coast along the Gulf of Mexico that covers the last 2000 years. The site witnessed the transformation of the environment since the early Olmec societies until forest clearance in the last century. Through these analyses we investigated the processes that affected the magnetic mineralogy in order to construct a model of past environmental changes, and compare this model with the archeological record and inferred climatic changes in the northern hemisphere of tropical America. Volcanic activity has played a major influence on sediment magnetic properties, as a purveyor of Ti-magnetites/Ti-maghemites, and as a factor of instability in the environment. Anoxic reductive conditions are evident in most of Lago Verde's sedimentary record. Direct observations of magnetic minerals and ratios of geochemical (Fe, Ti), and ferrimagnetic ( χf) and paramagnetic ( χp) susceptibility ( χ) data, are used as parameters for magnetite dissolution ( χp/ χ, Fe/ χf), and precipitation ( χf/Ti) of magnetic minerals. Intense volcanic activity and anoxia are recorded before A.D. 20, leading to the formation of framboidal pyrite. Increased erosion, higher evaporation rates, lower lake levels, anoxia and reductive diagenesis in non-sulphidic conditions are inferred for laminated sediments between A.D. 20-850. This deposit matches the period of historical crisis and multiyear droughts that contributed to the collapse of the Maya civilization. Dissolution of magnetite, a high organic content and framboidal pyrite point to anoxic, sulphidic conditions and higher lake levels after A.D. 850. Higher lake levels in Lago Verde broadly coincide with the increased precipitation documented during the Medieval Warm Period (A.D. 950-1350) in the northern tropical and subtropical regions of the American continent. For the Little Ice Age (A.D. 1400-1800), the relatively moist conditions

Neurodevelopmental delay among children under the age of three years at immunization clinics in Lagos State, Nigeria - Preliminary report.

PubMed

Bakare, Muideen O; Bello-Mojeed, Mashudat A; Munir, Kerim M; Ogun, Oluwayemi C; Eaton, Julian

2016-04-29

Late diagnosis and interventions characterize childhood neurodevelopmental disorders in Sub-Saharan Africa. This has negatively impacted on the prognosis of the children with neurodevelopmental disorders. This study examined the prevalence and pattern of neurodevelopmental delays among children under the age of 3 years attending immunization clinics in Lagos State, Nigeria and also affords opportunity of early follow-up and interventions, which had been documented to improve prognosis. The study involved two stage assessments; which consisted of first phase screening of the children for neurodevelopmental delays in immunization clinics at primary healthcare centers Lagos State, Nigeria and second phase which consists of definitive clinical evaluation and follow-up interventions for children screened positive for neurodevelopmental delays. Twenty seven (0.9%) of a total of 3,011 children under the age of 3 years were screened positive for neurodevelopmental delays and subsequently undergoing clinical evaluation and follow-up interventions. Preliminary working diagnoses among these children include cerebral palsy, autism spectrum disorder trait, nutritional deficiency, Down syndrome and Non-specific neurodevelopmental delay with co-morbid seizure disorder accounting for 33.3%, 14.8%, 18.5%, 7.4% and 25.9% respectively. This is a preliminary report that would be followed up with information on medium and long term intervention phase.

Comparative assessment of blood lead levels of automobile technicians in organised and roadside garages in Lagos, Nigeria.

PubMed

Saliu, Abdulsalam; Adebayo, Onajole; Kofoworola, Odeyemi; Babatunde, Ogunowo; Ismail, Abdussalam

2015-01-01

Occupational exposure to lead is common among automobile technicians and constitutes 0.9% of total global health burden with a majority of cases in developing countries. The aim of this study was to determine and compare the blood lead levels of automobile technicians in roadside and organised garages in Lagos State, Nigeria. This was a comparative cross-sectional study. Data were collected using interviewer-administered questionnaires. Physical examinations were conducted and blood was analysed for lead using atomic spectrophotometery. Statistical analyses were performed to compare the median blood lead levels of each group using the independent sample (Mann-Whitney U) test. Seventy-three (40.3%) of the organised compared to 59 (34.3%) of the roadside groups had high blood lead levels. The organised group had statistically significant higher median blood lead levels of, 66.0 µg/dL than the roadside 43.5 µg/dL (P < 0.05). There was also statistically significant association between high blood lead levels and abnormal discolouration of the mucosa of the mouth in the organised group. Automobile technicians in organised garages in Lagos have higher prevalence of elevated blood lead levels and higher median levels than the roadside group. Preventive strategies against lead exposures should be instituted by the employers and further actions should be taken to minimize exposures, improve work practices, implement engineering controls (e.g., proper ventilation), and ensure the use of personal protective equipment.

Comparative Assessment of Blood Lead Levels of Automobile Technicians in Organised and Roadside Garages in Lagos, Nigeria

PubMed Central

Saliu, Abdulsalam; Adebayo, Onajole; Kofoworola, Odeyemi; Babatunde, Ogunowo; Ismail, Abdussalam

2015-01-01

Occupational exposure to lead is common among automobile technicians and constitutes 0.9% of total global health burden with a majority of cases in developing countries. The aim of this study was to determine and compare the blood lead levels of automobile technicians in roadside and organised garages in Lagos State, Nigeria. This was a comparative cross-sectional study. Data were collected using interviewer-administered questionnaires. Physical examinations were conducted and blood was analysed for lead using atomic spectrophotometery. Statistical analyses were performed to compare the median blood lead levels of each group using the independent sample (Mann-Whitney U) test. Seventy-three (40.3%) of the organised compared to 59 (34.3%) of the roadside groups had high blood lead levels. The organised group had statistically significant higher median blood lead levels of, 66.0 µg/dL than the roadside 43.5 µg/dL (P < 0.05). There was also statistically significant association between high blood lead levels and abnormal discolouration of the mucosa of the mouth in the organised group. Automobile technicians in organised garages in Lagos have higher prevalence of elevated blood lead levels and higher median levels than the roadside group. Preventive strategies against lead exposures should be instituted by the employers and further actions should be taken to minimize exposures, improve work practices, implement engineering controls (e.g., proper ventilation), and ensure the use of personal protective equipment. PMID:25759723

The direct hospitalization cost of care for acute burns in Lagos, Nigeria: a one-year prospective study

PubMed Central

Ahachi, C.N.; Fadeyibi, I.O.; Abikoye, F.O.; Chira, M.K.; Ugburo, A.O.; Ademiluyi, S.A.

2011-01-01

Summary Objective. We conducted a prospective study to identify the direct hospitalization cost of managing major acute burns in Lagos, Nigeria, and to determine the factors that influence the cost. Method. All consecutive and consenting patients seen and managed for major burns at the National Orthopaedic Hospital, Igbobi, Lagos, between 1 June 2007 and 31 May 2008 were recruited for the study. A special form designed for the study was used to collect the necessary data. Results. Fifty-two patients were seen during the study period (27 males and 25 females). The ages ranged from 2 months to 69 yr with a mean of 25.4 ± 17.1 yr. The length of hospital stay ranged from 0.3-12 months (mean, 3.2 ± 3.1 months). The average daily cost of treating a patient was ₦ (naira) 8,855 (₦1000 = €4.44) and the average overall cost was ₦209,303.70, with the costs of wound dressings, hospital admission, and surgery constituting respectively 29.5%, 25.7%, and 19.1% of the total amount spent. Conclusion. The length of hospital stay was prolonged in many patients and management methods should be reviewed to reduce this. The cost of managing burns is prohibitive for an average Nigerian. Efforts should be intensified to prevent burn injury and a Special Health Insurance policy should be established to finance burns management. PMID:22262967

Changes in the prevalence of dental caries in primary school children in Lagos State, Nigeria.

PubMed

Sofola, O O; Folayan, M O; Oginni, A B

2014-01-01

To evaluate the changes in the prevalence of dental caries in Lagos State over a 3 years period and the role of age, sex, and playing in the changes observed. Three primary schools in Lagos State, Nigeria were randomly selected for the study. Six hundred and thirty-three children age 2-12 years, were examined for caries in 2000 while 513 children were examined in 2003. The prevalence of tooth decay and the prevalence of untreated tooth decay were calculated for the two years, that is, 2000 and 2003. Also the degree of unmet treatment need among the population with caries experience was measured. Differences in the prevalence and severity of dental caries in the primary and permanent dentition were assessed. Approximately 18% of children had untreated tooth decay in their primary dentition in 2003: A 26.1% increase from 2000. About 12.0% of the decay, extracted, and filled teeth (deft) index was seen with decayed teeth in 2000 and 16.6% in 2003. Extracted primary teeth decreased from 2.5% in 2000 to 1.5% in 2003. The change in mean deft between 2000 (0.42) and 2003 (0.47) was 11.9%. Over the study period, the overall reduction in the prevalence of dental caries was 34.8% in the permanent dentition. The decline was larger among children aged 5-9 years (62.1%) and among females (75%). The study showed no overall changes in caries severity but a decrease in caries prevalence in the permanent dentition over the study period. The largest decline in caries prevalence in the permanent dentition was observed in children aged 5-9 years and females. On the contrary, there was an increase in the caries prevalence in the primary dentition.

First evidence of "paralytic shellfish toxins" and cylindrospermopsin in a Mexican freshwater system, Lago Catemaco, and apparent bioaccumulation of the toxins in "tegogolo" snails (Pomacea patula catemacensis).

PubMed

Berry, John P; Lind, Owen

2010-05-01

Exposure to cyanobacterial toxins in freshwater systems, including both direct (e.g., drinking water) and indirect (e.g., bioaccumulation in food webs) routes, is emerging as a potentially significant threat to human health. We investigated cyanobacterial toxins, specifically cylindrospermopsin (CYN), the microcystins (MCYST) and the "paralytic shellfish toxins" (PST), in Lago Catemaco (Veracruz, Mexico). Lago Catemaco is a tropical lake dominated by Cylindrospermopsis, specifically identified as Cylindrospermopsis catemaco and Cylindrospermopsis philippinensis, and characterized by an abundant, endemic species of snail (Pomacea patula catemacensis), known as "tegogolos," that is both consumed locally and commercially important. Samples of water, including dissolved and particulate fractions, as well as extracts of tegogolos, were screened using highly specific and sensitive ELISA. ELISA identified CYN and PST at low concentrations in only one sample of seston; however, both toxins were detected at appreciable quantities in tegogolos. Calculated bioaccumulation factors (BAF) support bioaccumulation of both toxins in tegogolos. The presence of CYN in the phytoplankton was further confirmed by HPLC-UV and LC-MS, following concentration and extraction of algal cells, but the toxin could not be confirmed by these methods in tegogolos. These data represent the first published evidence for CYN and the PST in Lago Catemaco and, indeed, for any freshwater system in Mexico. Identification of the apparent bioaccumulation of these toxins in tegogolos may suggest the need to further our understanding of the transfer of cyanobacterial toxins in freshwater food webs as it relates to human health. Copyright 2009 Elsevier Ltd. All rights reserved.

EFFECT OF TRIMETHOPRIM-SULFAMETHOXAZOLE PROPHYLAXIS ON FAECAL CARRIAGE RATES OF RESISTANT ISOLATES OF ESCHERICHIA COLI IN HIV-INFECTED ADULT PATIENTS IN LAGOS.

PubMed

Egwuatu, C C; Iwuafor, A A; Egwuatu, T O; Akujobi, C N; Nnachi, A U; Aghanya, I N; Ogunsola, F T; Oduyebo, O O

2016-01-01

The daily use of Trimethoprim-Sulfamethoxazole (TMP-SMX) prophylaxis reduces morbidity and mortality among patients infected with Human Immunodeficiency Virus (HIV) but its impact on increasing antimicrobial resistance rates has been of public concern globally. This study investigated the effect of daily TMP-SMX prophylaxis on faecal carriage rates of resistant isolates of Escherichia coli in HIV-infected adult patients in Lagos. A total of 550 HIV-infected patients with CD4-cell count of less than 350 cell/mm 3 and were eligible for TMP-SMX prophylaxis attending Lagos University Teaching Hospital, Lagos, Nigeria, were recruited. Stool/rectal swab samples were aseptically collected from the patients and processed using standard methods for culture and sensitivity. There was a baseline Trimethoprim-Sulfamethoxazole resistance rate of 54% which increased to 77.9% in first 3 months, rising to 96.1% by 6 months and all isolates were resistant by the 9th month. There was also evidence of cross-resistance to other antibiotics with significant association with TMP-SMX resistance (p<0.0001). The Escherichia coli isolates showed a progressive increase in resistance to the tested antibiotics over the 12-month period. The resistance was in the following order: Ampicillin (74% to 82.6% in the first 3 months; 98.3% by the 6th month and 99.4% by the 9th month; all isolates were resistant by the 12th month). Augmentin (32.5% to 47.7% in first 3 months; 76.1% by the 6th month; 86.3% by the 9th month; all isolates were resistant by 12 months). Ceftriaxone (2.0% to 10.8% in first 3 months; 20.6% by the 6th month; 24.2% by the 9th month; 54.3% by the 12 months). The carriage rate of faecal E. coli resistant to TMP-SMX is common before TMP-SMX prophylaxis. Initiation of TMP-SMX leads to further increase in resistance to TMP-SMX and cross-resistance to other antimicrobials.

A Science Centre as a Geoturism promoter - the Lagos Ciência Viva examples (Portugal).

NASA Astrophysics Data System (ADS)

Azevedo Rodrigues, Luis; Leote, Catarina

2017-04-01

Science outreach and engagement are crucial core objectives of the Lagos Ciência Viva Science Centre (CCVL). By engaging audiences in the real world a link is made between their science centre experience and the environment in which they live. Therefore, it has been an option of the CCVL to offer geological outdoor activities, both in the natural environment and urban context. Dinosaurs are an appealing science subject for both students and tourists. Thus, the CCVL has a long tradition in organizing and guiding field trips to two dinosaur track sites - Salema and Santa beaches (Vila do Bispo, southwest Algarve). These sites, both from the Lower Cretaceous reveal at least two types of tracks - theropod and iguanodontian footprints. Often in combination with the paleontology field trips, the CCVL also offers different geological field trips both for formal (school) and informal (tourism) education. This allows students and tourists to be introduced to dinosaur paleobiology and ichnology and to the structural geology and stratigraphy of the area. Our science outreach is being further developed by contractual agreement with a regional tour operator, in which the CCVL is responsible for the scientific content and guidance of the visits. Aiming at an urban context, the CCVL produced three Urban Geology and Paleontology Guide Books for three Algarve cities (Lagos, Faro and Tavira), which can be acquired in the three Ciência Viva Science Centres shops as well as in the tourist information offices serving this way as a basis for guided urban tours also offered by the CCVL. Based on our experience, we review and contextualise these geoscience activities and their potential for science outreach, communication and tourism. We discuss and propose a classification of different possibilities in geoscience communication and outreach based on three vertices: Science, Heritage and Geotourism. Some particularities of these visits, such as the merge between geosciences and other

Mass Burns Disaster in Abule-egba, Lagos, Nigeria from a Petroleum Pipeline Explosion Fire

PubMed Central

Fadeyibi, I.O.; Omosebi, D.T.; Jewo, P.I.; Ademiluyi, S.A.

2009-01-01

Summary The aim of this paper is to review the basic principles of triage in mass burns disasters and discuss the experience of the Lagos State University Teaching Hospital (LASUTH), Ikeja, Nigeria, in the December 2006 disaster at Abule-Egba, Lagos, Nigeria. It is hoped that the experience gained will help in the planning for and management of similar disasters in the developing countries with limited facilities. Burn injury has been described as the severest form of trauma and its management is very challenging as it is often accompanied by numerous pathophysiological changes. Successful management requires expert management by well-trained personnel in equipped and dedicated centres. In mass disasters the total number of victims may exceed the capability of the facility and its staff and a system for sorting out the patients and caring for those that will benefit from the facilities available needs to be developed. Other patients will either be sent to other medical facilities for further treatment or discharged after initial care for future follow-up. Documented experiences in the management of mass burns disasters from petroleum pipeline explosions from developing countries are rare. However, petroleum pipeline explosions, especially in the Lagos area of Nigeria, are relatively common. These cases have been associated with a variety of factors. The resulting morbidity and mortality have been high. LASUTH has a dedicated burns centre, which has received and managed many burn patients. Triage is the medical process of screening patients according to their need of treatment and the resources available. The aims and objectives of triage are discussed, its various levels described, and the final goals elaborated. All the burn victims involved in the 2006 disaster were studied, together with the triage carried out at different levels and the consequent sorting of the patients. Standard burns management was carried out. A total of 385 patients sustained burns of

Potential health risks due to telecommunications radiofrequency radiation exposures in Lagos State Nigeria.

PubMed

Aweda, M A; Ajekigbe, A T; Ibitoye, A Z; Evwhierhurhoma, B O; Eletu, O B

2009-01-01

The global system mobile telecommunications system (GSM) which was recently introduced in Nigeria is now being used by over 40 million people in Nigeria. The use of GSM is accompanied with exposure of the users to radiofrequency radiation (RFR), which if significant, may produce health hazards. This is the reason why many relevant national and international organizations recommended exposure limits to RFR and why it is made compulsory for GSM handsets to indicate the maximum power output as a guide to potential consumers. This study was conducted to measure the RFR output power densities (S) from the most commonly used GSM handsets used in Lagos State and compare with the limit recommended for safety assessment. Over 1100 most commonly used handsets of different makes and models as well as wireless phones were sampled and studied in all over the local government areas of the State. An RFR meter, Electrosmog from LESSEMF USA was used for the measurements. The handsets were assessed for health risks using the reference value of 9 Wm(-2) as recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The range of the S-values obtained varied from a minimum of 1.294 0.101 Wm(-2) with Siemens model R228 to a maximum of 16.813 +/- 0.094 Wm(-2) with Samsung model C140*. The results from wireless telephones showed very low S-values ranging from a minimum of 0.024 +/- 0.001 Wm(-2) with HUAWEI and ST CDMA 1 to a maximum of 0.093 +/- 0.002 Wm(-2) with HISENSE. The results showed that the population in Lagos State may be at risk due to significant RFR exposures resulting principally from the use of GSM. Quite a number of handsets emit power above the ICNIRP recommended value. Measured RFR power close to Radio and Television masts and transmitters are within tolerable limits in most cases, only that the public should not reside or work close to RFR installations. Phone calls with GSM should be restricted to essential ones while youths and children

A Late Holocene Record of Human Impact in the Tropical Lowlands of the Mexican Gulf Coast: Lago Verde.

NASA Astrophysics Data System (ADS)

Socorro, L.; Sosa, S.; Caballero, M.; Rodriguez, A.; Ortega, B.

2005-05-01

Lago Verde is a maar lake (18 36 43 N; 95 20 52 W) located on the Gulf Coast of Mexico in "Los Tuxtlas" region. The area was cover by tropical rain forest and is part of the core area of the earliest Mesoamerican cultures. A 6 m sediment core was obtained in order to document vegetation and lake level history of this area. Lago Verde is a shallow, eutrophic lake (max. 4 m), the natural vegetation has been removed and grasslands with some tropical trees such Bursera grows around the lake. According with the radiocarbon chronology the sequence covers the last 2500 yr BP. At the base of the sequence low abundance of tropical trees is record, with intermediate lake levels. A sudden change in the pollen stratigraphy occurs at ca. 2000 yr BP, with important presence of Poaceae, Ambrosia and Cheno.-Am. along with Zea mays indicating human activity in the area. This is associated with a change in limnological conditions, recording turbid, shallow environments. This pollen signals correlates with dry phases in Yucatan, suggesting that this dry climatic signal probably had effect on an ample area of Mexico. However, at 1200 yr BP, no more Zea mays pollen is recovered suggesting the abandonment of the area. Lake levels recover as well as the tropical forest. The last 150 yr BP is characterized by the reduction in the pollen of tropical forest trees, presence of Zea mays, increased erosion rates, turbidity and eutrophication in the lake, all related to deforestation.

Is there a step-wise migration in Nigeria? A case study of the migrational histories of migrants in Lagos.

PubMed

Afolayan, A A

1985-09-01

"The paper sets out to test whether or not the movement pattern of people in Nigeria is step-wise. It examines the spatial order in the country and the movement pattern of people. It then analyzes the survey data and tests for the validity of step-wise migration in the country. The findings show that step-wise migration cannot adequately describe all the patterns observed." The presence of large-scale circulatory migration between rural and urban areas is noted. Ways to decrease the pressure on Lagos by developing intermediate urban areas are considered. excerpt

Use of CD-ROM MEDLINE by medical students of the College of Medicine, University of Lagos, Nigeria.

PubMed

Ogunyade, Taiwo O; Oyibo, Wellington A

2003-01-01

Use of information technology in information acquisition, especially MEDLINE on CD-ROM and online, has been evaluated in several localities and regions, especially in the advanced countries. Use of MEDLINE on CD-ROM is still very poor among the medical students of the University of Lagos, Lagos, Nigeria, due to lack of awareness, insufficient personal computers, nonperiodic training, and the high cost of using the facility. Due to financial constraints, MEDLINE online and sufficiently-networked computer systems are not available. To report on the situation in Nigeria, a developing country, so as to compare the current awareness of searching MEDLINE on CD-ROM among the medical students at the University of Lagos with the awareness of their overseas' counterparts. This is the first step toward setting up an online PubMed search as well as expanding the computer systems and network. Essentially based on cross-sectional proportional sampling using structured questionnaires, in-depth interviews, and focus-group discussions among the medical students and library staff. The study involved the medical students in their second year to sixth (final) year of study. Of the 250 students interviewed, 130 (52%) were aware of MEDLINE on CD-ROM searches as a means of information retrieval. Only 60 (24%) had used MEDLINE on CD-ROM-2% had used MEDLINE on CD-ROM more than 9 times; 4%, 7 to 9 times; 8%, 4 to 6 times; and 10%, 1 to 3 times. Of the students who used MEDLINE on CD-ROM search, 22% used it in preparing for examinations, 24% in research, 6% in patient care, and 26% in preparation of assignments and clinical cases. Lack of awareness (52%) and cost of undertaking MEDLINE on CD-ROM search (46%) were identified as important factors that discouraged the use of MEDLINE on CD-ROM. Though the above factors were recognized as important, it was concluded that the reasons for the poor use of MEDLINE on CD-ROM are multifactorial. Poor use of MEDLINE on CD-ROM could be attributed to

Correlação de longo alcance em sistemas binários de raios-x usando remoção de flutuações

NASA Astrophysics Data System (ADS)

Pereira, M. G.; Moret, M. A.; Zebende, G. F.; Nogueira, E., Jr.

2003-08-01

Neste trabalho é proposta uma metodologia de analise de series temporais de fontes astrofísicas, baseada no método proposto por Peng et al. (1994) e Liu et al. (1999), o qual consiste na idéia de que uma série temporal correlacionada pode ser mapeada por um processo de busca de auto-similaridades em diversas escalas de tempo n. Removendo as eventuais tendências e integrando o sinal observado, é obtida uma medida do desvio médio quadrático das flutuações do sinal integrado F(n)~na, onde a representa o fator de escala associado com a auto-similaridade da correlação de longo alcance do sinal. Baseado nos valores obtidos de a, é possível distinguir entre os casos de sinais não-correlacionados, tipo ruído branco (a = 0,5), sinal anti-persistentes (a < 0,5) e sinal persistente (a > 0,5). Usando esta metodologia, foram analisadas 129 curvas de luz de sistemas binários de raios-X, provenientes do banco de dados públicos de observações feitas pelo instrumento All Sky Monitor, a bordo do satélite Rossi X-Ray Timing Explorer (ASM-RXTE). Foram identificadas a presença de a'0,5 em mais de 90% dos sistemas estudados, implicando em dizer que as flutuações de intensidade observadas apresentam correlação de auto-similaridade, sem entretanto, indícios de apresentarem uma escala de tempo característica das flutuações de intensidade. Sistemas onde são observadas erupções (flares), apresentam sistematicamente a > 0,5, característica esta, possivelmente associada com persistência das flutuações de densidade de disco ou taxa de acréscimo de massa. Os sistemas com curvas de luz onde nao são observadas as erupções apresentam uma distribuição normal centrada em a~0,62+/-0,10. Referências ¾ Peng, C.-K., Buldyrev, S.V., Havlin, S., Simons, M., Stanley, H.E., e Goldberg, A.L., Phys. Rev. E, (49), 1685 (1994). ¾ Liu, Y., Gopikrishnan, P., Cizeau, P., Meyer, M., Peng,C.-K., e Stanley, H.E., Phys. Rev. E, (60), 1390 (1999).

White mica K-Ar geochronology of HP-UHP units in the Lago di Cignana area, western Alps, Italy: Tectonic implications for exhumation

NASA Astrophysics Data System (ADS)

Gouzu, Chitaro; Yagi, Koshi; Thanh, Ngo Xuan; Itaya, Tetsumaru; Compagnoni, Roberto

2016-04-01

High-pressure and ultra-high pressure (HP-UHP) blueschist- and eclogite-facies metabasaltic and metasedimentary rocks occur in four different tectonic units near Lago di Cignana, western Alps. We have determined K-Ar ages for white micas (matrix phengite and paragonite) from the Lago di Cignana UHP unit (LCU; 39-41 Ma); the lower and upper units of the Zermatt-Saas meta-ophiolite (LU and UU; 37-38 Ma and 38-41 Ma respectively), and the Combin unit (CU; 36-40 Ma). These K-Ar ages overlap with single-grain Ar-Ar plateau ages (36-42 Ma) previously determined for phengites from LCU metasediments. Matrix white micas have been severely deformed during exhumation, and their chemistries differ from those of micas included in garnet. Although individual mica grains in the matrix could have experienced different degrees of deformation which have reset their K-Ar systems, "bulk" white mica separates provide the average age of all the individual grains in the separate. The similarity of ages determined for white micas from the LCU, LU, UU and CU units, regardless of rock type and mineral species, suggests that these four units were metamorphosed together as part of a single metamorphic sequence in the Piemonte-Liguria paleosubduction zone and were subsequently exhumed together. However, present-day structural relationship among those units and the limited occurrence of UHP minerals in LCU suggests that the exhumation of LCU was more rapid than that for LU, UU and CU. The age gaps between the youngest value of white mica K-Ar ages in each unit and the inferred timing of the metamorphic peak (U-Pb age: 44 Ma) is 5, 7, 6 and 8 Myr for LCU, LU, UU and CU, respectively. These intervals are considerably shorter than that determined for the Sanbagawa HP metamorphic belt of Southwest Japan (> 31 Myr). The short interval observed for the Lago di Cignana units that we have studied is consistent with the model of rapid exhumation of the UHP-bearing metamorphic domain, suggesting the

Determinants of Quality of Family Planning Counseling among Private Health Facilities in Lagos.

PubMed

Johnson, Doug; Ugaz, Jorge

2016-09-01

We use a unique dataset that includes an objective measure of the quality of family planning counseling from 927 private health facilities in Lagos State, Nigeria, to determine which variables at the facility and provider levels are most closely correlated with the quality of family planning counseling. Our data on quality come from mystery client surveys in which the clients posed as women seeking family planning counseling. We find that quality is strongly associated with the cadre of provider, with doctors delivering substantially higher-quality counselling than nurses. Doctors not only outperform nurses overall, but also perform better on each category of quality and spend nearly three minutes longer on average counseling the mystery client. Location, fees charged for the service, and facility type are also strongly correlated with quality. The degree to which a facility specializes in family planning and facility size are only weakly predictive of quality. © 2016 The Population Council, Inc.

Fertility and female employment in Lagos, Nigeria.

PubMed

Feyisetan, B J

1985-01-01

This paper investigates the relationship between fertility and female employment in a Nigerian urban center, Lagos. The study is built upon the data derived from the Survey of Household Structure, Family Employment, and the Small Family Ideal carried out in 1974. The study centered around currently married women aged 15-49, living in 2 residential areas chosen to include wage-earning and non wage-earning workers. It is principally a test of the maternal role incompatibility hypothesis, whose major tenet is that the maternal role and function of worker are incompatible with each other. On the basis of the assumption, the fertility and female employment equations are estimated by the 2 stage least squares procedure and estimated results compared to those derived from the ordinary least squares procedure. The results demonstrate that mothering and working tend to conflict only if employment is undertaken in the formal sector of the labor market; a positive association is discernable between the proclivity to engage in non-domestic but irregular activities of the informal sector and the bearing and rearing of children. While the conflict between fertility and female employment in the formal sector suggests possible trade-offs between the number of children and employment, the positive association between fertility and female employment in the informal sector suggests the compatibility of the roles of a mother and of a worker in that sector. The results further demonstrate the inadequacy of using a mere rural-urban dichotomy in the examination of the maternal role incompatibility hypothesis as done in some earlier works. The urban labor market, especially in a less developed country like Nigeria, needs formal disaggregation into formal and informal sectors on the basis of the activities being undertaken.

Female reproductive tract infections: understandings and care seeking behaviour among women of reproductive age in Lagos, Nigeria

PubMed Central

2010-01-01

Background Reproductive tract infections (RTI's) are endemic in developing countries and entail a heavy toll on women. If untreated, RTI's can lead to adverse health outcomes such as infertility, ectopic pregnancy and increased vulnerability to transmission of the human immunodeficiency virus. It is also associated with adverse pregnancy outcomes. While RTI's and its sequelae abound in Nigeria, there is paucity of publications on the subject in the country. This study assessed the understandings and care seeking behavior with regards to RTI's among women of reproductive age in Lagos, Nigeria with the aim of improving awareness on the subject. Methods A descriptive cross sectional survey of women attending the gynaecological outpatient and family planning clinics of the Lagos State University Teaching Hospital was carried out between 1st June 2008 and 31st August 2008 using a pre-tested questionnaire. Data was analysed using the Epi-Info 3.5 statistical software of the Centre for Disease Control and Prevention, Atlanta U.S.A. Results Most of the respondents (77.2%) had heard of RTI's. Toilet was the most perceived mode of contracting RTI's (44.6%), followed by sexual intercourse and poor hygiene. Vaginal discharge was the commonest symptom of RTI's named while inability to get pregnant was the commonest named complication. Majority of the respondent's demonstrated poor overall knowledge of symptoms and complications of RTI"s. 37.4% of the respondents had experienced symptoms of RTI's in the preceding six months. Vaginal discharge was the commonest symptom reported (21.8%) and the majority of those who reported symptoms sought medical treatment. Government health centres were the most visited health facilities for treatment. Conclusion Even though most of the respondents have heard of RTI's and sought treatment when symptomatic, they demonstrated poor overall understanding of the subject. There is need to educate women on preventive strategies, as RTI's are often

Prevalence of Malaria in Pregnant Women in Lagos, South-West Nigeria

PubMed Central

Agomo, Chimere O.; Anorlu, Rose I.; Agomo, Philip U.

2009-01-01

Prevalence rates reported for malaria in pregnancy in Nigeria vary considerably. The accuracy of results of malaria diagnosis is dependent on training, experience, and motivation of the microscopist as well as the laboratory facility available. Results of training programmes on malaria microscopy have shown low levels of sensitivity and specificity of those involved in malaria diagnosis routinely and for research. This study was done to ascertain the true prevalence of malaria in pregnancy in Lagos, South-West Nigeria. A total of 1,084 pregnant women were recruited into this study. Blood smears stained with Giemsa were used for malaria diagnosis by light microscopy. Malaria infection during pregnancy presents mostly as asymptomatic infection. The prevalence of malaria in this population was 7.7% (95% confidence interval; 6.2-9.4%). Factors identified to increase the risk of malaria infection include young maternal age (< 20 years), and gravidity (primigravida). In conclusion, this study exposes the over-diagnosis of malaria in pregnancy and the need for training and retraining of laboratory staffs as well as establishing the malaria diagnosis quality assurance programme to ensure the accuracy of malaria microscopy results at all levels. PMID:19488427

Vegetation history and palaeoclimate of the last glacial period at Lago Grande di Monticchio, Southern Italy

NASA Astrophysics Data System (ADS)

Watts, W. A.; Allen, J. R. M.; Huntley, B.

A high-resolution palynological study of a 51 m core from Lago Grande di Monticchio, southern Italy, has provided a palaeonvironmental record for the last glacill. A annual lamination based chronology, supported by radiometric and tephrochronological dates, provides an absolute timescale for this record that spans 76,300 years. Correlations are established between the pollen stratigraphy, the GRIP ice core δ18O record and foraminiferal assemblages from Atlantic core V23-81. Both Dansgaard-Oeschger and Heinrich events are reflected by changes in the pollen stratigraphy. Revised dates are estimated for Heinrich events H1-H6. A quantitative palaeoclimate reconstruction based upon the pollen data provides evidence of the climate changes in southern Italy associated with these and other fluctuations during the last glacial.

El Sistema's Open Secrets

ERIC Educational Resources Information Center

Booth, Eric

2011-01-01

In this article, the author talks about Venezuela's national youth orchestra program called El Sistema whose attributes offer a direct challenge to traditional Western music practices. As U.S. classical music--and all "high arts"--struggle to find relevance to more than the small "arts club" percentage of the U.S. populace, El…

Characteristics and risk factors of preterm births in a tertiary center in Lagos, Nigeria.

PubMed

Butali, Azeez; Ezeaka, Chinyere; Ekhaguere, Osayame; Weathers, Nancy; Ladd, Jenna; Fajolu, Iretiola; Esezobor, Christopher; Makwe, Christian; Odusanya, Bukola; Anorlu, Rose; Adeyemo, Wasiu; Iroha, Edna; Egri-Okwaji, Mathias; Adejumo, Prisca; Oyeneyin, Lawal; Abiodun, Moses; Badejoko, Bolaji; Ryckman, Kelli

2016-01-01

Preterm birth is a dire complication of pregnancy that poses huge long-term medical and financial burdens for affected children, their families, and the health care system. The aim of the present study was to identify characteristics associated with preterm births at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria from 2011 to 2013. We obtained Information from 5,561 maternal, fetal/neonatal and obstetric records from the labor ward. We excluded delivery at less than 22 weeks (0.25%), post-term birth at ≥42 weeks gestation (1.3%), and unknown gestation (1.4%). Additionally, we excluded records of multiple births (5.4%) and stillbirths (8.3%) leaving 4,691 records of singleton live-births for analysis. Logistic regression analysis was performed comparing preterm birth (22-36 weeks gestation) to term birth (37-41 weeks gestation). Multiple variable models adjusting for maternal age, parity, fetal position, delivery method and booking status were also evaluated. Multinomial regression was used to identify characteristics associated with preterm birth (PTB) defined as early PTB (22-31 weeks gestation), moderate PTB (32-34 weeks gestation), late PTB (35-36 weeks gestation), compared to term birth (37-41 completed weeks gestation). From our data, 16.8% of the singleton live-birth deliveries were preterm (<37 weeks gestation). Of these, 4.7% were early (22-31 weeks), 4.5% were moderate (32-34 weeks) and 7.7% were late (35-36) PTBs. Older maternal age (≥35 years) [odds ratio (OR) = 1.41], hypertension (OR = 3.44) and rupture of membranes (OR = 4.03) were significantly associated with increased odds of PTB. Women being treated for the prevention of mother-to-child transmission of HIV were at a significantly decreased risk for PTB (OR = 0.70). Sixteen percent of women in this cohort were not registered for antenatal care in LUTH. These non-registered subjects had significantly greater odds of all categories of PTB, including early (odds ratio (OR) = 20

Complementary Feeding Knowledge, Practices, and Dietary Diversity among Mothers of Under-Five Children in an Urban Community in Lagos State, Nigeria

PubMed Central

Olatona, Foluke Adenike; Adenihun, Jesupelumi Oreoluwa; Aderibigbe, Sunday Adedeji; Adeniyi, Oluwafunmilayo Funke

2017-01-01

Background and Objectives: Inappropriate complementary feeding is a major cause of child malnutrition and death. This study determined the complementary feeding knowledge, practices, minimum dietary diversity, and acceptable diet among mothers of under-five children in an urban Local Government Area of Lagos State, Southwest Nigeria. Methods: This descriptive cross-sectional study was conducted in Eti-Osa area of Lagos State, Nigeria. Multi-stage sampling technique was employed to select 355 mothers and infants. Data was collected using a pre-tested interviewer administered questionnaire and 24-hour diet recall was used to assess dietary diversity. Data was analyzed using Epi-Info. Results: Knowledge of complementary feeding was low (14.9%) and was associated with older mothers’ age, being married, and higher level of education. The prevalence of timely initiation of complementary feeding (47.9%), dietary diversity (16.0%) and minimum acceptable diet for children between 6 and 9 months (16%) were low. Overall, appropriate complementary feeding practice was low (47.0%) and associated with higher level of mothers’ education and occupation. Conclusions and Global Health Implications: Complementary feeding knowledge and practices were poor among mothers of under-5 especially the non-literate. Reduction of child malnutrition through appropriate complementary feeding remains an important global health goal. Complementary feeding education targeting behavioral change especially among young, single and uneducated mothers in developing countries is important to reduce child morbidity and mortality. PMID:28798893

Sistemas Correctores de Campo Para EL Telescopio Cassegrain IAC80

NASA Astrophysics Data System (ADS)

Galan, M. J.; Cobos, F. J.

1987-05-01

El proyecto de instrumentación de mayor importancia que ha tenido el Instituto de Astrofisica de Canarias en los últimos afios ha sido el diseflo y construcción del te1escopio IAC8O. Este requería del esfuerzo con junto en mec´nica, óptica y electrónica, lo que facilitó la estructuración y el crecimiento de los respectivos grupos de trabajo, que posteriormente se integraron en departamentos En su origen (1977), el telescopio IAC80 fue concebido como un sistema clásico tipo Cassegrain, con una razón focal F/i 1.3 para el sistema Casse grain y una razón focal F/20 para el sistema Coudé. Posteriormente, aunque se mantuvo la filosofia de que el sistema básico fuera el F/11.3, se consideró conveniente el diseño de secundarios para razones focales F/16 y F/32, y se eliminó el de F/20. Sin embargo, dada la importancia relativa que un foco estrictamente fotográfico tiene en un telescopio moderno, diseñado básicamente para fotometría fotoeléctrica y con un campo util mínimamente de 40 minutos de arco, se decídió Ilevar a cabo el diseño de un secundario F/8 con un sistema corrector de campo, pero que estuviera formado únicamente por lentes con superficies esféricas para que asl su construcción fuera posible en España ó en México. La creciente utilización de detectores bidimensionales para fines de investigación astron6mica y la viabilidad de que en un futuro cercano éstos tengan un área sensible cada vez mayor, hicieron atractiva la idea de tener diseñado un sistema corrector de campo para el foco primario (F/3), con un campo útil mínimo de un grado, y también con la limitante de que sus componentes tuvieron sólamente supérficies esféricas. Ambos diseños de los sis-temas correctores de campo se llevaron a cabo, en gran medida, como parte de un proyecto de colaboración e intercambio en el área de diseño y evaluación de sistemas ópticos.

Climatic and anthropogenic forcing of prehistorical vegetation succession and fire dynamics in the Lago di Como area (N-Italy, Insubria)

NASA Astrophysics Data System (ADS)

Martinelli, Elisa; Michetti, Alessandro Maria; Colombaroli, Daniele; Mazzola, Eleonora; Motella De Carlo, Sila; Livio, Franz; Gilli, Adrian; Ferrario, Maria Francesca; Höbig, Nicole; Brunamonte, Fabio; Castelletti, Lanfredo; Tinner, Willy

2017-04-01

Combined pollen, charcoal and modeling evidence from the Insubria Region suggests that fire was a major driver of late Holocene vegetation change. However, the extent and timing of fire response dynamics are not clear yet. We use lacustrine sediments from Lago di Como (N-Italy, S-Alps) to assess if the reconstructed vegetation and fire dynamics were relevant at large scales and if they coincided in time with those observed at smaller sites. The lake, due to its size (142 km2) and economic potential, was very attractive for early land use and human presence in this area is well documented since ca. 10,000 yrs ago (Mesolithic). We used pollen, plant macrofossils and charcoal to reconstruct the vegetation composition and fire activity. During the Younger Dryas and the Early Holocene until ca. 8000 cal BP natural dynamics prevailed. Subsequently, land use and slash-and-burn activities increased at the Mesolithic-Neolithic transition and became widespread around ca. 6500 cal BP. Microscopic charcoal and numerical analyses demonstrate that anthropogenic fires had a determinant influence on long-term vegetation dynamics at regional scales in Insubria. Microscopic charcoal and pollen and spores indicative of land use show that human pressure intensified after ca. 5300 cal yr BP and even more since ca. 4300 cal yr BP. Our results suggest that important species which disappeared or were strongly reduced by land use and fire (e.g. Abies alba, Tilia, Ulmus) will potentially reestablish in the Lago di Como area and elsewhere in Insubria, if land abandonment initiated in the 1950s will continue.

Change in fish fauna as indication of aquatic ecosystem condition in Rio Grande de Morelia-Lago de Cuitzeo Basin, Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soto-Galera, E.; Paulo-Maya, J.; Lopez-Lopez, E.

1999-07-01

The Rio Grande de Morelia-Lago de Cuitzeo basin in west central Mexico has experienced major increases in water pollution from a rapidly growing human population. The authors examined changes in the long-term distribution of fishes in relation to water quality and quantity in order to assess the condition and health of aquatic ecosystems in the basin. Sampling between 1985 and 1993 revealed that five (26%) of the 19 native fish species known from the basin had been extirpated. Two of these were endemics, Chirostoma charari and C. compressum, and they are presumed extinct. Twelve (63%) of the remaining species hadmore » declines in distribution. Sixteen (80%) of the 20 localities sampled had lost species. The greatest declines occurred in Lago de Cuitzeo proper and in the lower portion of the Rio Grande de Morelia watershed. Species losses from the lake were attributable to drying and hypereutrophication of the lake because of substantial reductions in the amount and quality of tributary inputs, whereas losses from the Rio Grande de Morelia watershed were the result of pollution from agricultural, municipal, and industrial sources, especially in the region around the city of Morelia. Three localities in the upper portion of the Rio Grande de Morelia watershed--Cointzio reservoir, La Mintzita spring, and Insurgente Morelos stream--contained most of the remaining fish species diversity in the basin and deserve additional protection. Fish faunal changes indicated major declines in the health of aquatic ecosystems in the Morelia-Cuitzeo basin.« less

U-Pb zircon geochronologycal investigation on the Morro dos Seis Lagos Carbonatite Complex and associated Nb deposit (Amazonas, Brazil)

NASA Astrophysics Data System (ADS)

Rossoni, Marco B.; Bastos Neto, Artur C.; Souza, Valmir S.; Marques, Juliana C.; Dantas, Elton; Botelho, Nilson F.; Giovannini, Arthur L.; Pereira, Vitor P.

2017-12-01

We present results of U-Pb dating (by MC-ICP-MS) of zircons from samples that cover all of the known lithotypes in the Seis Lagos Carbonatite Complex and associated lateritic mineralization (the Morro dos Seis Lagos Nb deposit). The host rock (gneiss) yielded an age of 1828 ± 09 Ma interpreted as the crystallization time of this unit. The altered feldspar vein in the same gneiss yielded an age of 1839 ± 29 Ma. Carbonatite samples provided 3 groups of ages. The first group comprises inherited zircons with ages compatible with the gneissic host rock: 1819 ± 10 Ma (superior intercept), 1826 ± 5 Ma (concordant age), and 1812 ± 27 Ma (superior intercept), all from the Orosirian. The second and the third group of ages are from the same carbonatite sample: the superior intercept age of 1525 ± 21 Ma (MSWD = 0.77) and the superior intercept age of 1328 ± 58 Ma (MSWD = 1.4). The mineralogical study indicates that the ∼1.3 Ga zircons have affinity with carbonatite. It is, however, a tendence rather than a well-defined result. The data allow state that the age of 1328 ± 58 Ma represents the maximum age of the carbonatite. Without the same certainty, we consider that the data suggest that this age may be the carbonatite age, whose emplacement would have been related to the evolution of the K'Mudku belt. The best age obtained in laterite samples (a superior intercept age of 1828 ± 12 Ma) is considered the age of the main source for the inherited zircons related to the gneissic host rock.

High-risk of obstructive sleep apnea and excessive daytime sleepiness among commercial intra-city drivers in Lagos metropolis

PubMed Central

Ozoh, Obianuju B.; Okubadejo, Njideka U.; Akanbi, Maxwell O.; Dania, Michelle G.

2013-01-01

Background: The burden of obstructive sleep apnea among commercial drivers in Nigeria is not known. Aim: To assess the prevalence of high risk of obstructive sleep apnea (OSA) and excessive daytime sleepiness (EDS) among intra-city commercial drivers. Setting and Design: A descriptive cross-sectional study in three major motor parks in Lagos metropolis. Materials and Methods: Demographic, anthropometric and historical data was obtained. The risk of OSA and EDS was assessed using the STOP BANG questionnaire and the Epworth Sleepiness Scale, respectively. Statistical Analysis: The relationship between the OSA risk, EDS risk and past road traffic accident (RTA) was explored using the Pearson's chi square. Independent determinants of OSA risk, EDS risk and past RTA, respectively, were assessed by multiple logistic regression models. Result: Five hundred male commercial drivers (mean age (years) ±SD = 42.36 ± 11.17 and mean BMI (kg/m2) ±SD = 25.68 ± 3.79) were recruited. OSA risk was high in 244 (48.8%) drivers and 72 (14.4%) had EDS. There was a positive relationship between OSA risk and the risk of EDS (Pearson's X2 = 28.2, P < 0.001). Sixty-one (12.2%) drivers had a past history of RTA but there was no significant relationship between a past RTA and either OSA risk (X2 = 2.05, P = 0.15) or EDS risk (X2 = 2.7, P = 0.1), respectively. Abdominal adiposity, regular alcohol use and EDS were independent determinants of OSA risk while the use of cannabis and OSA risk were independent determinants of EDS. No independent risk factor for past RTA was identified. Conclusion: A significant proportion of commercial drivers in Lagos metropolis are at high risk of OSA and EDS. PMID:24249946

The growth history of the Lago Della Vacca (Southern Adamello Massive, Italy) intrusion from field observations, thermal and rheological modelling

NASA Astrophysics Data System (ADS)

Rust, A.; Annen, C.; Blundy, J. D.; Caricchi, L.

2010-12-01

The Lago Della Vacca granitoid is an intrusive body emplaced at about 4-6 km in up to 1 My. The core of the body is characterised by the presence of dyke-like structures, enclave-swarms and randomly distributed enclaves, which appear undeformed. Enclaves become oblate with the short axis perpendicular to the foliation, which, in turn follows the margin of the plutonic body (John and Blundy, 1993). Geothermometry and experimental data have been used to constrain the temperature of injection of the mafic component (1273-1323 K), the temperature of the host granitic magma (1173-1223), and to characterise the evolution of crystallinity with temperature for both magmas (Blundy and Sparks, 1992). Based on these data thermal and rheological modelling have been combined to interpret the growth and deformation history of the Lago della Vacca intrusive body. The pluton was modeled as a series of incrementally emplaced nested cylinders with 1D-cylindrical conductive heat transfer. The evolution of temperature and melt fraction distribution in the pluton and country rock were determined and used as input parameters for the rheological modelling. The rheology of each magma depends on the viscosity of the melt and, more importantly, on crystallinity. Field observations suggest that the mafic magma was injected as dykes. Their partial or total disaggregation produced mafic enclaves. The presence of randomly distributed enclaves in the core of Lago Della Vacca body indicates that convection was active in this portion of the intrusion. The undeformed nature of the enclaves in this region also implies that the contrast in temperature between host magma and mafic material produced a sudden (hours) rheological inversion with the mafic magma becoming more viscous than the felsic end-member. In these conditions, the enclaves would be transported passively by the felsic-host without suffering any substantial deformation. Thermal modelling indicates that to maintain the core of the pluton

Epidemiology of psychoactive drug use amongst adolescents in metropolitan Lagos, Nigeria.

PubMed

Famuyiwa, Oluwole; Aina, Olatunji F; Bankole-Oki, Olufunlayo M

2011-07-01

The study was conducted in response to the lack of epidemiological data in recent time on the use of psychoactive substances by adolescents in metropolitan Lagos-a city unique for its socio-economic profile. We considered some methodological issues omitted in several previous studies. A total of 4,286 school pupils (mean age 15.2) were anonymously administered a Self-Report Questionnaire to ascertain a range of key drug use factors in lifetime and 1-year periods. The rate of use of most of the 14 substances investigated was much higher than reported in any other study on comparable population sample. We found that 61.8 and 32.1% of respondents have used one or more substances in their lifetime and in the past 1 year, respectively. High lifetime rates of use were found for common stimulants: coffee, kolanut, and prescription drugs (barbiturates and minor tranquilisers). The rate of use of proscribed addictive substances, cannabis, heroin, and cocaine, ranged between 4.0 and 4.8%. Missing data and non-response rates were few; however, social acquiescence, under and over reporting, could be mitigant to estimation of rates and patterns of use. We advocate properly articulated school-based educative programmes that can facilitate drug demand reduction.

Sistemas de cúmulos globulares extragalácticos

NASA Astrophysics Data System (ADS)

Forte, J. C.

Se describen las características de los sistemas de cúmulos globulares asociados a galaxias elípticas en una variedad de medios y, en particular, aquellas vinculadas con la distribución espacial, frecuencia específica y composición química. Esta discusión se hace dentro de un conjunto de esquemas orientados a explicar las primeras fases de la formación de las galaxias dominantes en cúmulos y del rol de los sistemas de cúmulos globulares en esos procesos.

HOLOCENE MASS-WASTING EVENTS IN LAGO FAGNANO, TIERRA DEL FUEGO (54°S): IMPLICATIONS FOR PALEOSEISMICITY OF THE MAGALLANES-FAGNANO TRANSFORM FAULT

NASA Astrophysics Data System (ADS)

Ariztegui, D.; Waldmann, N.; Austin, J. A.; Anselmetti, F.; Moy, C.; Dunbar, R. B.

2009-12-01

High-resolution seismic imaging and sediment coring in Lago Fagnano, located along the Magallanes-Fagnano plate boundary in Tierra del Fuego, have revealed a chronologic catalog of Holocene mass-wasting events. These event layers are interpreted as resulting from slope instabilities that load the slope-adjacent lake floor during mass flow deposition thus mobilizing basin floor sediments through gravity spreading. A total of 22 mass flow deposits have been identified combining results from an 800 km-long dense grid of seismic profiles with a series of sediment cores. Successions of up to 6 m-thick mass-flow deposits pond the basin floor spreading eastward and westward following the main axis of the eastern sub-basin of Lago Fagnano. An age model on the basis of information from previous studies and from new radiocarbon dating allowed establishing a well-constrained chronologic mass-wasting event catalogue covering the last ~15000 years. Simultaneously-triggered basin-wide lateral slope failure and the formation of multiple debris flow and megaturbidite deposits are interpreted as the fingerprint of paleo-seismic activity along the Magallanes-Fagnano transform fault that runs along the entire lake basin. The slope failures and megaturbidites are interpreted as recording large earthquakes occurring along the transform fault since the early Holocene. The results from this study provide new data about the frequency and possible magnitude of Holocene earthquakes in Tierra del Fuego, which can be applied in the context of seismic hazard assessment in southernmost Patagonia.

Review article: A review and critical analysis of the efforts towards urban flood risk management in the Lagos region of Nigeria

NASA Astrophysics Data System (ADS)

Nkwunonwo, U. C.; Whitworth, M.; Baily, B.

2016-02-01

Urban flooding has been and will continue to be a significant problem for many cities across the developed and developing world. Crucial to the amelioration of the effects of these floods is the need to formulate a sound flood management policy, which is driven by knowledge of the frequency and magnitude of impacts of these floods. Within the area of flood research, attempts are being made to gain a better understanding of the causes, impacts, and pattern of urban flooding. According to the United Nations office for disaster reduction (UNISDR), flood risk is conceptualized on the basis of three integral components which are frequently adopted during flood damage estimation. These components are: probability of flood hazard, the level of exposure, and vulnerabilities of elements at risk. Reducing the severity of each of these components is the objective of flood risk management under the UNISDR guideline and idea of "living with floods". On the basis of this framework, the present research reviews flood risk within the Lagos area of Nigeria over the period 1968-2012. During this period, floods have caused harm to millions of people physically, emotionally, and economically. Arguably over this period the efforts of stakeholders to address the challenges appear to have been limited by, amongst other things, a lack of reliable data, a lack of awareness amongst the population affected, and a lack of knowledge of flood risk mitigation. It is the aim of this research to assess the current understanding of flood risk and management in Lagos and to offer recommendations towards future guidance.

Resurrection Symphony: "El Sistema" as Ideology in Venezuela and Los Angeles

ERIC Educational Resources Information Center

Fink, Robert

2016-01-01

The explosive growth of Venezuela's "El Sistema" is rewriting the agenda of musical education in the West. Many commentators from the world of classical music react to the spectacle of dedicated young colonial musicians playing European masterworks as a kind of "miracle," accepting "Sistema" founder José Antonio…

Lifting the Veil: A Realist Critique of Sistema's Upwardly Mobile Path

ERIC Educational Resources Information Center

Logan, Owen

2016-01-01

El Sistema sits somewhere between a social project and a classical music initiative. However, its promise of delivering upward mobility has not been sufficiently examined as a structural phenomenon which dovetails with critical policy issues in taxation, educational provision, human rights, and welfare. This article argues that Sistema-style…

Characteristics and risk factors of preterm births in a tertiary center in Lagos, Nigeria

PubMed Central

Butali, Azeez; Ezeaka, Chinyere; Ekhaguere, Osayame; Weathers, Nancy; Ladd, Jenna; Fajolu, Iretiola; Esezobor, Christopher; Makwe, Christian; Odusanya, Bukola; Anorlu, Rose; Adeyemo, Wasiu; Iroha, Edna; Egri-Okwaji, Mathias; Adejumo, Prisca; Oyeneyin, Lawal; Abiodun, Moses; Badejoko, Bolaji; Ryckman, Kelli

2016-01-01

Introduction Preterm birth is a dire complication of pregnancy that poses huge long-term medical and financial burdens for affected children, their families, and the health care system. The aim of the present study was to identify characteristics associated with preterm births at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria from 2011 to 2013. Methods We obtained Information from 5,561 maternal, fetal/neonatal and obstetric records from the labor ward. We excluded delivery at less than 22 weeks (0.25%), post-term birth at ≥42 weeks gestation (1.3%), and unknown gestation (1.4%). Additionally, we excluded records of multiple births (5.4%) and stillbirths (8.3%) leaving 4,691 records of singleton live-births for analysis. Logistic regression analysis was performed comparing preterm birth (22-36 weeks gestation) to term birth (37-41 weeks gestation). Multiple variable models adjusting for maternal age, parity, fetal position, delivery method and booking status were also evaluated. Multinomial regression was used to identify characteristics associated with preterm birth (PTB) defined as early PTB (22-31 weeks gestation), moderate PTB (32-34 weeks gestation), late PTB (35-36 weeks gestation), compared to term birth (37-41 completed weeks gestation). Results From our data, 16.8% of the singleton live-birth deliveries were preterm (<37 weeks gestation). Of these, 4.7% were early (22-31 weeks), 4.5% were moderate (32-34 weeks) and 7.7% were late (35-36) PTBs. Older maternal age (≥35 years) [odds ratio (OR) = 1.41], hypertension (OR = 3.44) and rupture of membranes (OR = 4.03) were significantly associated with increased odds of PTB. Women being treated for the prevention of mother-to-child transmission of HIV were at a significantly decreased risk for PTB (OR = 0.70). Sixteen percent of women in this cohort were not registered for antenatal care in LUTH. These non-registered subjects had significantly greater odds of all categories of PTB, including

Thoughts on Seeing "El Sistema"

ERIC Educational Resources Information Center

Booth, Eric

2009-01-01

The FESNOJIV (the Spanish acronym for the State Foundation for the National System of Youth and Children's Orchestras), more commonly known as "El Sistema," teaches 300,000 of Venezuela's poorest children in the nationwide music learning program. Many begin attending the "nucleo" as early as age two or three, and the vast…

Knowledge Exchange with Sistema Scotland

ERIC Educational Resources Information Center

Allan, Julie; Moran, Nikki; Duffy, Celia; Loening, Gica

2010-01-01

This paper reports on a knowledge exchange project, funded by the Scottish Funding Council and undertaken by a group of researchers from three higher education institutions in Scotland and the project partner, Sistema Scotland. This newly established charity is attempting to implement a major programme of social change, developed in Venezuela,…

Knowledge, perceptions and practice of cervical cancer prevention among female public secondary school teachers in Mushin local government area of Lagos State, Nigeria

PubMed Central

Toye, Mariam Adeola; Okunade, Kehinde Sharafadeen; Roberts, Alero Ann; Salako, Omolola; Oridota, Ezekiel Sofela; Onajole, Adebayo Temitayo

2017-01-01

Introduction Cervical cancer is the most common gynecological cancer and a leading cause of cancer death in women in Nigeria. This study was aimed to assess the knowledge, perception, and practice of cervical cancer prevention among female public secondary school teachers in Mushin, Lagos. Methods This was a cross-sectional study carried out among female secondary school teachers in Mushin, Lagos. The participants were selected by a two-stage random sampling method and relevant data were collected with the use a self-administered questionnaire. Data entry and analysis were done using Epi-info version 7.2 statistical software and descriptive statistics were computed for all data. Results The knowledge of cervical cancer and its prevention was 100.0% among the respondents. The most commonly known method of cervical cancer screening identified by the respondents was Papanicolaou smear (91.4%). More than half of the women (67.0%) have had at least one cervical cancer screening done previously. Only 2.2% of the respondents have had HPV vaccine given to their female teenage children in the past despite the acceptance rate for HPV vaccination being 76.2%. Conclusion This study, unlike most previous studies in other regions of Nigeria and most part of sub-Saharan Africa, has demonstrated a relatively high level of awareness about cervical cancer, its cause, risk factors and prevention. However, conversely, the absence of a national health programme means that screening and vaccination centers are not available, accessible or affordable. PMID:29629007

Struggling for Integration: Universalist and Separatist Discourses within El Sistema Sweden

ERIC Educational Resources Information Center

Bergman, Åsa; Lindgren, Monica; Saether, Eva

2016-01-01

This article focuses on the El Sistema programme, which started up in Sweden in 2010 with the objective to deal with segregation problems typical for Swedish urban areas. The purpose of the article is to examine how promoting integration through music and music education is constructed within El Sistema as a way to help children growing up in…

Tides and lake-level variations in the great Patagonian lakes: Observations, modelling and geophysical implications.

NASA Astrophysics Data System (ADS)

Marderwald, Eric; Richter, Andreas; Horwath, Martin; Hormaechea, Jose Luis; Groh, Andreas

2016-04-01

In Patagonia, the glacial-isostatic adjustment (GIA) to past ice-mass changes (Ivins & James 2004; Klemann et al. 2007) is of particular interest in the context of the determination of the complex regional rheology related to plate subduction in a triple-junction constellation. To further complicate the situation, GIA is overlaid with load deformation not only due to present ice mass changes but also due to water-level changes in the lakes surrounding the icefields and the ocean surrounding Patagonia. These elastic deformations affect the determination of glacial-isostatic uplift rates from GPS observations (Dietrich et al. 2010; Lange et al. 2014). Observations of lake tides and their comparison with the theoretical tidal signal have been used previously to validate predictions of ocean tidal loading and have revealed regional deviations from conventional global elastic earth models (Richter et al. 2009). In this work we investigate the tides and lake-level variations in Lago Argentino, Lago Viedma, Lago San Martín/O'Higgins and Lago Buenos Aires/General Carrera. This allows us to test, among other things, the validity of tidal loading models. We present pressure tide-gauge records from two sites in Lago Argentino extending over 2.5 years (Richter et al. 2015). These observations are complemented by lake-level records provided by the Argentine National Hydrometeorological Network. Based on these lake-level time series the principal processes affecting the lake level are identified and quantified. Lake-level changes reflecting variations in lake volume are dominated by a seasonal cycle exceeding 1 m in amplitude. Lake-volume changes occur in addition with a daily period in response to melt water influx from surrounding glaciers. In Lago Argentino sporadic lake-volume jumps are caused by bursting of the ice dam of Perito Moreno glacier. Water movements in these lakes are dominated by surface seiches reaching 20 cm in amplitude. A harmonic tidal analysis of the lake

Herbal medicine use among urban residents in Lagos, Nigeria

PubMed Central

2011-01-01

Background Over three-quarter of the world's population is using herbal medicines with an increasing trend globally. Herbal medicines may be beneficial but are not completely harmless. This study aimed to assess the extent of use and the general knowledge of the benefits and safety of herbal medicines among urban residents in Lagos, Nigeria. Methods The study involved 388 participants recruited by cluster and random sampling techniques. Participants were interviewed with a structured open- and close-ended questionnaire. The information obtained comprises the demography and types of herbal medicines used by the respondents; indications for their use; the sources, benefits and adverse effects of the herbal medicines they used. Results A total of 12 herbal medicines (crude or refined) were used by the respondents, either alone or in combination with other herbal medicines. Herbal medicines were reportedly used by 259 (66.8%) respondents. 'Agbo jedi-jedi' (35%) was the most frequently used herbal medicine preparation, followed by 'agbo-iba' (27.5%) and Oroki herbal mixture® (9%). Family and friends had a marked influence on 78.4% of the respondents who used herbal medicine preparations. Herbal medicines were considered safe by half of the respondents despite 20.8% of those who experienced mild to moderate adverse effects. Conclusions Herbal medicine is popular among the respondents but they appear to be ignorant of its potential toxicities. It may be necessary to evaluate the safety, efficacy and quality of herbal medicines and their products through randomised clinical trial studies. Public enlightenment programme about safe use of herbal medicines may be necessary as a means of minimizing the potential adverse effects. PMID:22117933

Physical health status of pupils in a school for the mentally disabled in Lagos.

PubMed

Ezeaka, V C; Iroha, E O

2003-12-01

The study set out to assess the health status of pupils of a school for children with mental disability. The school is Modupe Cole Memorial Child Care and Treatment Home School, Akoka, Lagos. The records of 211 pupils were reviewed and the pupils were clinically examined by the author. Seventy-four (35.1%) of the subjects had complete immunization, 48(22.7%) had incomplete immunization while 44(20.9%) received no immunization. The probable aetiology of mental disability in the subjects was due to postnatal causes (96; 45.5%), natal causes (44; 20.8%), prenatal causes (12; 5.7%) and unknown (59; 28.0%). The most abnormal findings on physical examination were in the central nervous system (199; 94.3%), the musculoskeletal system (137; 64.9%), the mouth/teeth (125; 59.2%) and the skin (98; 46.4%). These findings were worse amongst the residential students than in the non-residential students (p < 0.001). The information obtained from this study will help to serve as a reference for purposes of health planning and policy formulation for children with mental disability.

El problema de estabilidad de los sistemas Hamiltonianos multidimensionales

NASA Astrophysics Data System (ADS)

Cincotta, P. M.

Se revisarán los aspectos básicos del problema de estabilidad de sistemans Hamiltonianos N-dimensionales, haciendo especial énfasis en los posibles mecanismos que dan lugar a la aparición de ``caos": overlap de resonancias, difusión de Arnol'd y otros procesos difusivos alternativos. Se mencionarán los aspectos aún no resueltos sobre la estabilidad de los sistemas con N > 2. Finalmente, se discutirá cuáles de estos mecanismos podrían tener alguna relevancia en la dinámica de sistemas estelares y planetarios.

Ocular findings seen among the staff of an institution in Lagos, Nigeria.

PubMed

Ashaye, A O; Asuzu, M C

2005-01-01

The degree to which ocular morbidity affects workers productivity in the developing countries has not been studied adequately. A federal government research institute based in Lagos introduced an annual health screen for all its workers, which included eye tests. This provided an opportunity to study the pattern of ocular conditions among workers who were 30 years and above, and to determine the effect of eye diseases on the workers productivity. Detailed eye examination including refraction, was done on every respondent at the institution's clinic by an ophthalmologist. A questionnaire on ocular health status and occupational history was administered independently by an ophthalmic nurse. Sickness absenteeism, use of the clinic were obtained from clinic records, and the results were analysed. The common ocular conditions were uncorrected or poorly corrected refractive error, uncorrected or poorly corrected presbyopia and allergic. conjunctivitis. Glaucoma, maculopathy and optic atrophy were causes of severe visual impairment or blindness in 1.9 % of the subjects. Absenteeism and clinic use were more common in subjects with ocular morbidity than those with non-ocular morbidity. Subjects with ocular morbidity had more illnesses, absenteeism and used the clinic more. Ocular problems which reduce worker's productivity are prevalent among the staff of the institution studied. They are mostly unrecognised.

Resonances and Tides in Natural Satellites Systems. (Breton Title: Ressonâncias e Marés em Sistemas de Satélites Naturais.) Resonancias y Mareas en Sistemas de Satélites Naturales

NASA Astrophysics Data System (ADS)

Callegari, Nelson, Jr.

2006-12-01

�sica, e não a descrição detalhada dos conceitos aqui discutidos. Describimos en este trabajo algunos aspectos de la dinámica de resonancias de movimientos promedio. Será dado un énfasis mayor al caso de las resonancias entre satélites regulares de los planetas gigantes, aunque también son discutidos brevemente algunos aspectos de la física de resonancias en sistemas panetarios extrasolares. La importancia del estudio de las resonancias en sistemas de satélites es discutida más detalladamente através de ejemplos, mostrando cómo ciertas resonancias y los efectos de disipación por mareas pueden ser la clave de parte de la explicación de algunos fenómenos aún no comprendidos en el Sistema Solar. Entre varios ejemplos se destacan el problema de la superficie remodelada del satélite Enceladus, la existencia de volcanes activos en Io y la posible existencia de un océano subterráneo en Europa. Este trabajo tiene como objetivo la divulgación de algunos tópicos en Mecánica Celeste y Planetología para un público universitario de ciencias exactas, en particular Astronomía y Física, y no la descripción detallada de los conceptos aquí discutidos.

On efeito do achatamento nos pontos de equilíbrio e na dinâmica de sistemas coorbitais

NASA Astrophysics Data System (ADS)

Mourão, D. C.; Winter, O. C.; Yokoyama, T.

2003-08-01

Neste trabalho analisamos o efeito do achatamento do corpo principal nos pontos de equilíbrio lagrangianos e na configuração de órbitas girino-ferradura. Enfatizamos os sistemas coorbitais de satélites de Saturno, pois se encontram em relativa proximidade com o planeta, em que o efeito do achatamento se torna mais evidente. O estudo é dividido em três etapas independentes. Na primeira fase analisamos as equações de movimento do problema restrito de três corpos considerando o efeito do achatamento, e através do balanceamento de forças buscamos a nova configuração dos pontos de equilíbrio lagrangianos. Concluímos, nesta etapa, que os pontos de equilíbrio estáveis apresentam um pequeno deslocamento definido pelo parâmetro de achatamento, não podendo ser mais representados por triângulos eqüiláteros. Aplicamos este resultado aos satélites coorbitais de Tetis e Dione, encontrando as posições de equilíbrio levemente deslocadas em relação ao caso sem achatamento. Na segunda fase visamos o sistema Saturno-Jano-Epimeteu, que por se tratar de um sistema de massas comparáveis, optamos por desenvolver as equações de Yoder et al (Icarus 53, pág 431-443, 1983), que permitem determinar os pontos de equilíbrio e a amplitude de oscilação angular das órbitas girino-ferradura para o problema não-restrito de três corpos, porém, no nosso estudo consideramos o efeito do achatamento do corpo principal nestas equações. Encontramos que a distância angular entre satélites, quando em posição de equilíbrio estável, diminui quanto maior for o parâmetro de achatamento do corpo principal. Além disso, a órbita de transição girino-ferradura possui largura angular menor em relação ao caso sem achatamento. Por fim, realizamos integrações numéricas para os casos reais de coorbitais de Saturno comparando com os resultados analíticos. Nestas integrações simulamos diversas órbitas girino-ferradura com diferentes parâmetros de achatamento

Hatching Plans: Pedagogy and Discourse within an El Sistema-Inspired Music Program

ERIC Educational Resources Information Center

Dobson, Nicolas

2016-01-01

In this article, I draw on my experience as an instrumental tutor with a music program inspired by and explicitly linked to El Sistema, to explore new perspectives on Sistema-based pedagogy and management. Detailed ethnographic description of an orchestral session provides a first-hand account of the program's pedagogy, which I then contextualize…

Multichannel analysis of the surface waves of earth materials in some parts of Lagos State, Nigeria

NASA Astrophysics Data System (ADS)

Adegbola, R. B.; Oyedele, K. F.; Adeoti, L.; Adeloye, A. B.

2016-09-01

We present a method that utilizes multichannel analysis of surface waves (MASW), which was used to measure shear wave velocities, with a view to establishing the probable causes of road failure, subsidence and weakening of structures in some local government areas in Lagos, Nigeria. MASW data were acquired using a 24-channel seismograph. The acquired data were processed and transformed into a two-dimensional (2-D) structure reflective of the depth and surface wave velocity distribution within a depth of 0-15 m beneath the surface using SURFSEIS software. The shear wave velocity data were compared with other geophysical/ borehole data that were acquired along the same profile. The comparison and correlation illustrate the accuracy and consistency of MASW-derived shear wave velocity profiles. Rigidity modulus and N-value were also generated. The study showed that the low velocity/ very low velocity data are reflective of organic clay/ peat materials and thus likely responsible for the failure, subsidence and weakening of structures within the study areas.

El Sistema Fundamentals in Practice: An Examination of One Public Elementary School Partnership in the US

ERIC Educational Resources Information Center

Simpson Steele, Jamie

2017-01-01

El Sistema is a Venezuelan program of social change that has inspired a worldwide movement in music education. El Sistema inspires social transformation and musical excellence to occur simultaneously and symbiotically. This study examines: What does El Sistema look like within the context of a public school partnership in the United States? How do…

Diverticular disease at colonoscopy in Lagos State, Nigeria.

PubMed

Oluyemi, Aderemi; Odeghe, Emuobor

2016-01-01

The upsurge in the reported cases of diverticular disease (DD) has led to a re-appraisal of the earlier held views that it was a rare entity in Nigeria. The advent of colonoscopy has contributed in no small way to this change. We sought to determine the clinical characteristics, indications for colonoscopy, and intra-procedural findings among these patients. A retrospective cross-sectional study was carried out on the colonoscopy records from four private endoscopy units based in Lagos State, Nigeria. The records were drawn from a 5-year period (August 2010 to July 2015). The endoscopy logs and reports were reviewed, and the bio data, indications, and colonoscopy findings were gleaned. A total of 265 colonoscopies were carried out in the stated period. Of these, 28 (10.6%) had DD. Of the patients with DD, 5 (17.9%) were females while 23 (82.1%) were males. Their ages ranged from 46 to 94 years (mean = 68.2 ± 11 years). Fifteen patients had been referred for the procedure on account of hematochezia alone (15 = 53.6%). Other reasons for referral included abdominal pain alone (2 = 7%), hematochezia plus abdominal pain (5 = 17.9%), and change in bowel habits (3 = 10.8%). Ten (35%) patients had pan-colonic involvement. Regional disease involved the right side alone in only one case (3.5%) while the other combinations of sites are as follows; 6 (21.4%) in the sigmoid colon alone, 2 (7%) in the descending colon alone, 5 (17.9%) in the sigmoid-descending colon, 4 (14.3%) in the sigmoid-descending-transverse colon, thus the sigmoid colon was involved in 25 (89.3%) cases. Five cases (17.9%) had endoscopic features suggestive of diverticulitis. DD should no longer be regarded as a rare problem in the Nigerian patient. The study findings support the notion of higher prevalence among the elderly, in males, and of sigmoid colon involvement.

A Retrospective Study of the Health Profile of Neonates of Mothers with Anemia in Pregnancy and Pregnancy Induced Hypertension in Lagos, Nigeria.

PubMed

Sotunde, Olusola Funmilayo; Sanni, Silifat Ajoke; Onabanjo, Oluseye Olusegun; Olayiwola, Ibiyemi O; Agbonlahor, Mure

2014-06-29

Our study assessed the health profile of neonates in relation to anemia in pregnancy and pregnancy induced hypertension (PIH). This was a retrospective study where a systematic random sampling technique was used to select a total of 1046 case records of pregnant women registered for ante-natal care at Lagos Island Maternity Hospital, Lagos, Nigeria, between 2005 and 2009. Socio-demographic characteristics of the mothers, prevalence of anemia and PIH, and neonatal health profile were obtained from the case records and were analyzed using both descriptive and inferential statistics. Pearson product moment correlation was used to show the relationship (P≤0.05) between maternal complications and neonatal health profile. Majority (68.8%) of the mothers had anemia and 6.7 % had PIH. Majority (97.12%) of the neonates were live births and 2.88% of the neonates were still births, 65.4% of the women with still birth pregnancy outcome had anemia, and 34.6% had PIH. Majority (74%) of the neonates had birth weight within normal range (2.5-4.0 kg) and majority (68%) had normal Apgar score at 5 min of birth (7-10). A positive correlation existed between the packed cell volume of the mother and the birth weight of the neonates (r=0.740, P≤0.05). A negative correlation existed between the incidence of PIH and the birth weight of the neonates (r= 0.781, P≤0.05), head circumference (r=-0.491, P≤0.05) and the length of the neonates(r=-0.480, P≤0.05). We conclude that nutritional and health care intervention programmes for pregnant women should be intensified especially during ante-natal visits to hospitals.

Modelizacion, control e implementacion de un procesador energetico paralelo para aplicacion en sistemas multisalida

NASA Astrophysics Data System (ADS)

Ferreres Sabater, Agustin

Cualquier sistema electronico que incluya un procesado o tratamiento de la senal, y ademas, algun tipo de actuador mecanico generalmente necesita, como minimo, dos tensiones diferentes de alimentacion. Excluyendo los sistemas de alimentacion distribuida, la solucion tecnica mas utilizada para proporcionar dos o mas tensiones consiste en las fuentes de alimentacion multisalida. En una fuente de alimentacion multisalida los diferentes circuitos que conforman cada salida comparten un mismo transformador de potencia optimizando coste, masa, y volumen. Las ventajas obtenidas con este procedimiento tienen en su contra el efecto que sobre cada salida individual provocan las demas en su conjunto debido, principalmente, a los efectos de los elementos parasitos de los componentes. Un cambio de carga en una de las salidas produce un transitorio que es visto por todas las demas como un efecto de impedancia cruzada, y al final del transitorio, la tension de cada salida es diferente respecto a la que tenian antes del transitorio. Este ultimo resultado se conoce como regulacion cruzada. La disminucion de los efectos de la regulacion cruzada ha sido objeto de estudio durante los ultimos anos. El objetivo ha sido el desarrollo de distintas estrategias que permiten, desde disminuir los efectos de la regulacion cruzada hasta los niveles deseables, a eliminarla completamente. El resultado final suele suponer una penalizacion sobre el diseno del sistema directamente proporcional al grado de regulacion a conseguir en las distintas salidas. Entre las soluciones propuestas para eliminar la regulacion cruzada las tecnicas de post-regulacion se han consolidado como la opcion mas aceptada ya que, pueden aplicarse a cualquier convertidor y no suponen ninguna complejidad adicional a la hora de plantear el diseno. En esta Tesis Doctoral se abordara el estudio de la tecnica conocida como postregulacion mediante transformador controlado, que si bien se ha empleado en convertidores resonantes, su

Evaluation of outcomes of tuberculosis management in private for profit and private-not-for profit directly observed treatment short course facilities in Lagos State, Nigeria.

PubMed

Adejumo, Olusola Adedeji; Daniel, Olusoji James; Otesanya, Andrew Folarin; Salisu-Olatunj, Shukrat Olajumoke; Abdur-Razzaq, Husseine A

2017-01-01

The engagement of private practitioners in the public-private mix of tuberculosis (TB) management started in 2007 in Lagos State Nigeria. This study compared the treatment outcomes of patients managed at private for profit (PFP) and private not for profit (PNFP) directly observed treatment short course (DOTS) facilities. A retrospective review of treatment cards of TB patients managed between January 1, 2012, and June 30, 2012, in seven PFP and four PNFP DOTS facilities that served as treatment and microscopy center under the Lagos State TB and Leprosy Control Programme (LSTBLCP) at least 2 years before data collection was conducted. A total of 372 treatment cards of TB patients were reviewed, of which 132 (35.5%) and 240 (64.5%) were from PFP and PNFP DOTS facilities, respectively. Treatment success rate was higher among patients managed at PFP (89.4%) DOTS facilities than PNFP (81.3%) DOTS facilities ( P = 0.04). The proportion of patients lost to follow-up (12.5% vs. 8.3%), dead (3.3% vs. 1.5%) and treatment failure (2.5% vs. 0.8%) was higher among patients managed at PNFP DOTS facilities ( P > 0.05). The odds that patients treated at PFP DOTS facilities had treatment success were about four times higher than PNFP DOTS facilities when other variables have been controlled for ( P < 0.05). There is need by the LSTBLCP to engage more private practitioners to increase case detection and improve treatment outcomes of TB patients.

A multi-proxy lake core record from Lago Lungo, Rieti Basin, Lazio, Italy and its relation to human activities in the catchment during the last century

NASA Astrophysics Data System (ADS)

Noble, Paula; Tunno, Irene; Mensing, Scott; Piovesan, Gianluca

2016-04-01

The lakes of the Rieti Basin have experienced extensive human modification dating back to pre-Roman times, yet lake archives indicate that the most profound changes to the aquatic ecosystem have occurred during the last century. Analysis of the upper ˜120 cm segment of a sediment core from Lago Lungo, dating back to ˜1830 CE, show changes in water quality and hydrologic inflow largely attributed to 20th century reclamation and land use activities. Lago Lungo is a shallow, small, eutrophic, hard water lake situated in an intermontaine alluvial plain ˜90 km NE of Rome. It is one of several remnant lakes in a poorly drained wetland area fed by numerous springs. Reclamation activities over the last century have substantially altered the drainage network affecting water delivery to the lakes and their connectivity. There are 3 interesting signals in the core. First, small Stephanodiscus species, associated with hypereutrophic conditions, appear after 1950, peak ˜1990, and may be attributed to increased use of chemical fertilizers and intensification of local agriculture. Elemental proxies from scanning XRF data (abundances of Ti, Si/Ti, and Ca) are consistent with increased eutrophication starting ˜1950. A decline in Stephanodicsus after 1990 reflects some improvement to the water quality following the lake's incorporation into a nature preserve and creation of a narrow vegetation buffer. Intermittent water quality measurements from 1982 onward corroborate the changes in trophic status interpreted from the core record. Second, a large change in the core stratigraphy, elemental geochemistry, and diatom composition occurs ˜1940 and is associated with several major reclamation efforts, including the rerouting of the Santa Susanna channel, which redirected large volumes of artesian inflows away from the lakes and estuarine system. Upstream, dams on the Turano and Salto rivers were also constructed, further affecting hydrological inflows into the basin. From ˜1900

Transactional sex, condom and lubricant use among men who have sex with men in Lagos State, Nigeria.

PubMed

Ayoola, Oluyemisi O; Sekoni, Adekemi O; Odeyemi, Kofoworola A

2013-12-01

Men who have unprotected sex with men may also have unprotected sex with women and thus serve as an epidemiological bridge for HIV to the general population. This cross sectional descriptive study assessed condom and lubricant use and practice of transactional sex among men who have sex with men (MSM) in Lagos state. Simple random sampling was used to select three community centres and snowball sampling technique was used to recruit 321 respondents. Almost half (50.9%) had received payment for sex while 45.4% had paid for sex in the past. Consistent condom use was practiced by 40.5% of respondents during the last 10 sexual encounters, 85.6% used lubricants mostly with condom, products used were KY jelly, body cream, saliva and Vaseline. There is need for behavioural change to reduce risky practices which predisposes this group of MSM to HIV and sexually transmitted infections.

Educational intervention and the health seeking attitude and adherence to therapy by tuberculosis patients from an urban slum in lagos Nigeria.

PubMed

Olayemi, S O; Oreagba, I A; Akinyede, A; Adepoju, G E

2009-12-01

Community based participation has been advocated by a number of international health organisations including the World Health Organization (WHO) as a solution to the problems of poor patient adherence and default from Directly Observed Treatment Short course [DOTs] programmes for tuberculosis control. To determine the impact of a health educational intervention on the management of tuberculosis in relation to the outcome and adherence to therapy by Tuberculosis patients residing in a densely populated urban slum in Lagos, Nigeria. The study was conducted using forty tuberculosis patients (confirmed by acid fast bacilli positive sputum), and selected randomly from those who attend the Mainland Hospital in Lagos. They were divided into two groups of twenty each made up of those to be provided with education intervention at the community level and the control groups followed up at the hospital level only. An initial assessment of the knowledge about tuberculosis management was done through a structured questionnaire for both groups. This was followed by continuous health talks for intervention group in form of neighbourhood self help approach. The results showed that the intervention had a significant impact on the understanding of disease and its management (X(2) =11.842 p<0.05), DOTS and increased awareness (X(2) =17.289 p<0.05, X(2) =10.461 p<0.05), knowing the side effects of anti-TB drugs (X(2) =10.157 p<0.05), the meaning of resistance to anti-Tuberculosis drugs (X(2) =19.798 p<0.05, X(2) =11.192 p<0.05) and importance of contact tracing (X(2) =32.4 p<0.05, X(2) =3.360 p<0.05). An effective health education is therefore beneficial for TB control in Nigeria.

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes.

PubMed

Soranno, Patricia A; Bacon, Linda C; Beauchene, Michael; Bednar, Karen E; Bissell, Edward G; Boudreau, Claire K; Boyer, Marvin G; Bremigan, Mary T; Carpenter, Stephen R; Carr, Jamie W; Cheruvelil, Kendra S; Christel, Samuel T; Claucherty, Matt; Collins, Sarah M; Conroy, Joseph D; Downing, John A; Dukett, Jed; Fergus, C Emi; Filstrup, Christopher T; Funk, Clara; Gonzalez, Maria J; Green, Linda T; Gries, Corinna; Halfman, John D; Hamilton, Stephen K; Hanson, Paul C; Henry, Emily N; Herron, Elizabeth M; Hockings, Celeste; Jackson, James R; Jacobson-Hedin, Kari; Janus, Lorraine L; Jones, William W; Jones, John R; Keson, Caroline M; King, Katelyn B S; Kishbaugh, Scott A; Lapierre, Jean-Francois; Lathrop, Barbara; Latimore, Jo A; Lee, Yuehlin; Lottig, Noah R; Lynch, Jason A; Matthews, Leslie J; McDowell, William H; Moore, Karen E B; Neff, Brian P; Nelson, Sarah J; Oliver, Samantha K; Pace, Michael L; Pierson, Donald C; Poisson, Autumn C; Pollard, Amina I; Post, David M; Reyes, Paul O; Rosenberry, Donald O; Roy, Karen M; Rudstam, Lars G; Sarnelle, Orlando; Schuldt, Nancy J; Scott, Caren E; Skaff, Nicholas K; Smith, Nicole J; Spinelli, Nick R; Stachelek, Joseph J; Stanley, Emily H; Stoddard, John L; Stopyak, Scott B; Stow, Craig A; Tallant, Jason M; Tan, Pang-Ning; Thorpe, Anthony P; Vanni, Michael J; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C; Webster, Katherine E; White, Jeffrey D; Wilmes, Marcy K; Yuan, Shuai

2017-12-01

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600-12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales. © The Author 2017. Published by Oxford University Press.

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes

PubMed Central

Bacon, Linda C; Beauchene, Michael; Bednar, Karen E; Bissell, Edward G; Boudreau, Claire K; Boyer, Marvin G; Bremigan, Mary T; Carpenter, Stephen R; Carr, Jamie W; Christel, Samuel T; Claucherty, Matt; Conroy, Joseph D; Downing, John A; Dukett, Jed; Filstrup, Christopher T; Funk, Clara; Gonzalez, Maria J; Green, Linda T; Gries, Corinna; Halfman, John D; Hamilton, Stephen K; Hanson, Paul C; Henry, Emily N; Herron, Elizabeth M; Hockings, Celeste; Jackson, James R; Jacobson-Hedin, Kari; Janus, Lorraine L; Jones, William W; Jones, John R; Keson, Caroline M; King, Katelyn B S; Kishbaugh, Scott A; Lathrop, Barbara; Latimore, Jo A; Lee, Yuehlin; Lottig, Noah R; Lynch, Jason A; Matthews, Leslie J; McDowell, William H; Moore, Karen E B; Neff, Brian P; Nelson, Sarah J; Oliver, Samantha K; Pace, Michael L; Pierson, Donald C; Poisson, Autumn C; Pollard, Amina I; Post, David M; Reyes, Paul O; Rosenberry, Donald O; Roy, Karen M; Rudstam, Lars G; Sarnelle, Orlando; Schuldt, Nancy J; Scott, Caren E; Smith, Nicole J; Spinelli, Nick R; Stachelek, Joseph J; Stanley, Emily H; Stoddard, John L; Stopyak, Scott B; Stow, Craig A; Tallant, Jason M; Thorpe, Anthony P; Vanni, Michael J; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C; Webster, Katherine E; White, Jeffrey D; Wilmes, Marcy K; Yuan, Shuai

2017-01-01

Abstract Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states. LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600–12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales. PMID:29053868

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes

USGS Publications Warehouse

Soranno, Patricia A.; Bacon, Linda C.; Beauchene, Michael; Bednar, Karen E.; Bissell, Edward G.; Boudreau, Claire K.; Boyer, Marvin G.; Bremigan, Mary T.; Carpenter, Stephen R.; Carr, Jamie W.; Cheruvelil, Kendra S.; Christel, Samuel T.; Claucherty, Matt; Collins, Sarah M.; Conroy, Joseph D.; Downing, John A.; Dukett, Jed; Fergus, C. Emi; Filstrup, Christopher T.; Funk, Clara; Gonzalez, Maria J.; Green, Linda T.; Gries, Corinna; Halfman, John D.; Hamilton, Stephen K.; Hanson, Paul C.; Henry, Emily N.; Herron, Elizabeth M.; Hockings, Celeste; Jackson, James R.; Jacobson-Hedin, Kari; Janus, Lorraine L.; Jones, William W.; Jones, John R.; Keson, Caroline M.; King, Katelyn B.S.; Kishbaugh, Scott A.; Lapierre, Jean-Francois; Lathrop, Barbara; Latimore, Jo A.; Lee, Yuehlin; Lottig, Noah R.; Lynch, Jason A.; Matthews, Leslie J.; McDowell, William H.; Moore, Karen E.B.; Neff, Brian; Nelson, Sarah J.; Oliver, Samantha K.; Pace, Michael L.; Pierson, Donald C.; Poisson, Autumn C.; Pollard, Amina I.; Post, David M.; Reyes, Paul O.; Rosenberry, Donald; Roy, Karen M.; Rudstam, Lars G.; Sarnelle, Orlando; Schuldt, Nancy J.; Scott, Caren E.; Skaff, Nicholas K.; Smith, Nicole J.; Spinelli, Nick R.; Stachelek, Joseph J.; Stanley, Emily H.; Stoddard, John L.; Stopyak, Scott B.; Stow, Craig A.; Tallant, Jason M.; Tan, Pang-Ning; Thorpe, Anthony P.; Vanni, Michael J.; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C.; Webster, Katherine E.; White, Jeffrey D.; Wilmes, Marcy K.; Yuan, Shuai

2017-01-01

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600–12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales.

Empowering or Boring? Discipline and Authority in a Portuguese Sistema-Inspired Orchestra Rehearsal

ERIC Educational Resources Information Center

Boia, Pedro S.; Boal-Palheiros, Graça

2017-01-01

El Sistema orchestras may be "transformative" and produce positive changes in the lives of young participants, but there are also negative aspects to discipline and authority that may lead to exclusion. This article positions itself within the current debate on Sistema by treating symmetrically its potentially positive and negative…

Knowledge of commercial bus drivers about road safety measures in Lagos, Nigeria.

PubMed

Okafor Ifeoma, P; Odeyemi Kofoworola, A; Dolapo Duro, C

2013-01-01

Road traffic injuries have persisted as a serious public health problem and much of the health burden is in developing countries. Over-speeding, poor enforcement of traffic regulations and commuter buses have been highly implicated in road traffic injuries in developing countries. The aim of this study was to determine drivers' knowledge of selected road safety measures, i.e. the pre-requisites for driver's license, road signs and speed limits. This was a cross-sectional study carried out in Lagos, Nigeria. Simple random sampling was used to select the two motor parks used for the study and all the consenting commercial minibus drivers operating within the parks (407) were included in the study. Data was collected with a pre-tested, structured, interviewer-administered questionnaire and analyzed with epi-info statistical software. Two hundred and sixty-one (64.1%) of them knew that Visual Acuity test should be done before obtaining driver's license and 53.8% knew the correct minimum age for obtaining driver's license. Only 1% of the drivers had correct knowledge of the driver's license authorities in Nigeria. The drivers had poor knowledge of road signs (59.0%) and poor knowledge of maximum speed limits (100%). The oldest, least educated and least experienced drivers had the poorest level of knowledge. The drivers demonstrated poor knowledge of road safety measures. There is need for driver education to improve their knowledge.

El Sistema and American Music Education

ERIC Educational Resources Information Center

Lesniak, Melissa

2012-01-01

The brainchild of Jose Antonio Abreu, El Sistema, a music education program for aspiring orchestra musicians launched in Venezuela for students of limited means and now spreading to other parts of the world, has become a subject of interest to music teachers and teacher educators in North America. This article examines a bit of the program's…

The effects of Hurricane Hugo on suspended-sediment loads, Lago Loiza Basin, Puerto Rico

USGS Publications Warehouse

Gellis, A.

1993-01-01

In the two main tributaries that enter Lago Loiza, Rio Grande de Loiza and Rio Gurabo, 99 600 tonnes of suspended sediment was transported by 58.2??106 m3 of runoff in a 48 h period. The storm-average suspended-sediment concentration in the Rio Grande de Loiza for Hurricane Hugo was 2290 mgl-1, the second lowest for the 12 storms that have been monitored at this site. In Rio Gurabo the storm-average suspended-sediment concentration was 1420 mg l -1, the sixth lowest recorded out of 15 monitored storms. In Quebrada Salvatierra, a small tributary to Rio Grande de Loiza, suspended-sediment concentrations were as low as 33 mg l-1 during peak runoff of 20m3s-1. Normally the suspended-sediment concentrations at this discharge are 300 mg l-1. Hurricane force winds seem to be the most important factor contributing to the lower than expected suspended-sediment loads. High winds caused vegetation and debris to be dislodged and displaced. Debris accumulated on hillslopes and in small channels, blocked bridges and formed debris dams. These dams caused local backwater effects that reduced stream velocities and decreased suspended-sediment loads. -from Author

Exposure to media content and sexual health behaviour among adolescents in Lagos metropolis, Nigeria.

PubMed

Wusu, Onipede

2013-06-01

The influence of adolescents' exposure to sexual health content of mass media in their sexual health behaviour in Nigeria is still not clear. Data were gathered through a survey conducted among adolescents aged 12-19 years in Lagos metropolis between November 2009 and February 2010. A multistage sampling strategy was adopted in selecting respondents. Logistic regression technique was utilised in the analysis. The results indicate that the respondents were most frequently exposed to TV (male = 92.2; female = 94.9) and radio (male = 88.2; female = 91.7) media. The odds ratios indicate that sexual health content of mass media significantly predicted condom use, multiple sexual relationship, sexual intercourse and self reported occurrence of abortion in the study sample. The findings imply that positive media sexual health content is likely to promote sexual health among adolescents but negative contents can put adolescents' sexual health in danger. In addition, safe sex can be advanced among adolescents if the media provide accurate information on sexuality, emphasising the dangers of risky sexual practices. Finally, this study posits that accurate portrayal of sexuality in the media would contribute immensely to improving public health in the metropolis.

A Retrospective Study of the Health Profile of Neonates of Mothers with Anemia in Pregnancy and Pregnancy Induced Hypertension in Lagos, Nigeria

PubMed Central

Sanni, Silifat Ajoke; Onabanjo, Oluseye Olusegun; Olayiwola, Ibiyemi O.; Agbonlahor, Mure

2014-01-01

Our study assessed the health profile of neonates in relation to anemia in pregnancy and pregnancy induced hypertension (PIH). This was a retrospective study where a systematic random sampling technique was used to select a total of 1046 case records of pregnant women registered for ante-natal care at Lagos Island Maternity Hospital, Lagos, Nigeria, between 2005 and 2009. Socio-demographic characteristics of the mothers, prevalence of anemia and PIH, and neonatal health profile were obtained from the case records and were analyzed using both descriptive and inferential statistics. Pearson product moment correlation was used to show the relationship (P≤0.05) between maternal complications and neonatal health profile. Majority (68.8%) of the mothers had anemia and 6.7 % had PIH. Majority (97.12%) of the neonates were live births and 2.88% of the neonates were still births, 65.4% of the women with still birth pregnancy outcome had anemia, and 34.6% had PIH. Majority (74%) of the neonates had birth weight within normal range (2.5-4.0 kg) and majority (68%) had normal Apgar score at 5 min of birth (7-10). A positive correlation existed between the packed cell volume of the mother and the birth weight of the neonates (r=0.740, P≤0.05). A negative correlation existed between the incidence of PIH and the birth weight of the neonates (r= 0.781, P≤0.05), head circumference (r=–0.491, P≤0.05) and the length of the neonates(r=–0.480, P≤0.05). We conclude that nutritional and health care intervention programmes for pregnant women should be intensified especially during ante-natal visits to hospitals. PMID:28299124

A geochemical and sedimentary record of high southern latitude Holocene climate evolution from Lago Fagnano, Tierra del Fuego

NASA Astrophysics Data System (ADS)

Moy, Christopher M.; Dunbar, Robert B.; Guilderson, Thomas P.; Waldmann, Nicolas; Mucciarone, David A.; Recasens, Cristina; Ariztegui, Daniel; Austin, James A.; Anselmetti, Flavio S.

2011-02-01

Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes. Here we describe a Holocene paleoclimate record from sediment cores obtained from Lago Fagnano, a large lake in southern Tierra del Fuego at 55°S, to investigate past changes in climate related to these two important features of the global climate system. We use an AMS radiocarbon chronology for the last 8000 yr based on pollen concentrates, thereby avoiding contamination from bedrock-derived lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcán Hudson eruption. Combining bulk organic isotopic (δ13C and δ15N) and elemental (C and N) parameters with physical sediment properties allows us to better understand sediment provenance and transport mechanisms and to interpret Holocene climate and tectonic change during the last 8000 yr. Co-variability and long-term trends in C/N ratio, carbon accumulation rate, and magnetic susceptibility reflect an overall Holocene increase in the delivery of terrestrial organic and lithogenic material to the deep eastern basin. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake. Superimposed on the long-term trend are a series of abrupt 9 negative departures in C/N ratio, which constrain the presence of seismically-driven mass flow events in the record. We identify an increase in bulk δ13C between 7000 and 5000 cal yr BP that we attribute to enhanced aquatic productivity driven by warmer summer temperatures. The Lago Fagnano δ13C record shows similarities with Holocene records of sea surface temperature from the mid-latitude Chilean continental

A Geochemical and Sedimentary Record of High Southern Latitude Holocene Climate Evolution from Lago Fagnano, Tierra del Fuego

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moy, C M; Dunbar, R B; Guilderson, T P

Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes. Here we describe a Holocene paleoclimate record from sediment cores obtained from Lago Fagnano, a large lake in southern Tierra del Fuego at 55{sup o}S, to investigate past changes in climate related to these two important features of the global climate system. We use an AMS radiocarbon chronology for the last 8,000 years based on pollen concentrates, thereby avoiding contamination from bedrock-derivedmore » lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcan Hudson eruption. Combining bulk organic isotopic ({delta}{sup 13}C and {delta}{sup 15}N) and elemental (C and N) parameters with physical sediment properties allow us to better understand sediment provenance and transport mechanisms and to interpret Holocene climate and tectonic change during the last 8,000 years. Co-variability and long-term trends in C/N ratio, carbon accumulation rate, and magnetic susceptibility reflect an overall Holocene increase in the delivery of terrestrial organic and lithogenic material to the deep eastern basin. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake. Superimposed on the long-term trend are a series of abrupt 9 negative departures in C/N ratio, which constrain the presence of seismically-driven mass flow events in the record. We identify an increase in bulk {delta}{sup 13}C between 7,000 and 5,000 cal yr BP that we attribute to enhanced aquatic productivity driven by warmer summer temperatures. The Lago Fagnano {delta}{sup 13}C record shows similarities with Holocene records of sea

A Holocene Record of Hydrological Fluctuations in the Northern Chilean Altiplano (Lago Chungará)

NASA Astrophysics Data System (ADS)

Valero-Garces, B. L.; Saez, A.; Pueyo, J.; Taberner, C.; Bao, R.; Schnurrenberger, D.; Myrbo, A.; Shapley, M.; Herrera, C.; Moreno-Caballud, A.; Gonzalez-Samperiz, P.; Giralt, S.; Oriol-Gibert, R.; Edwards, L.; Schwalb, A.

2004-12-01

Holocene records of moisture availability in the Central Andes and the Altiplano show contrasting and even opposite signals and time-transgressive millennial-scale climatic changes across the region, particularly between the Titicaca Basin and the Atacama Altiplano. A multiproxy study of a 13 kyr record of Lago Chungará (18° 15' S, 69° 10' W, 4520 m a.s.l.) provides new data to solve some of the paleoclimate controversies as regional moisture availability patterns during the early and mid Holocene and the onset of modern ENSO conditions. Lago Chungara originated after the emplacement of the Parinacota volcano debris avalanche that blocked the Chungará River prior to 13 cal. kyrs ago. A seismic survey and fifteen Kullenberg cores allowed a detailed 3-D reconstruction of the 8 m long sedimentary sequence. The chronological model is based on 5 AMS 14C on bulk organic matter and 3 U/Th dates on authigenic carbonates and shells. To assess the typically large (and variable) reservoir effect, we dated modern sediments and waters, and constrained the model with time markers based on a 210Pb age model for the last 150 yrs, volcanic ashes of known age, and the U/Th dates. We performed high-resolution analyses by an X-ray fluorescence core scanner and magnetic, sedimentological, mineralogical, isotopic, and biological (pollen, diatoms and ostracodes) analyses on selected cores. Statistical analyses helped to separate the volcanism from climate as the key driving forces in the hydrological and sedimentological evolution of the lake. Three main lacustrine units are identified on top of the pre Parinacota avalanche substrate. The basal unit (13 - 7.2 cal. kyrs BP) is a finely laminated diatomite. The middle unit (7.2 - 4.5 cal. kyrs BP) is banded and it is composed of diatomites and carbonate-rich layers. The diatomaceous upper unit (after 4.5 cal. kyrs BP) is banded to massive, and it contains abundant volcanic layers (lapilli, ash layers). Increased volcanic activity after

Parental determinants of offspring head circumference using a sample of patients attending a government hospital in Lagos, Nigeria.

PubMed

Taiwo, I A; Adeleye, A

2013-01-01

Head circumference at birth is an important neonatal parameter in view of its association with perinatal and postnatal morbidity and mortality. It is an indicator of brain volume and a tool for assessing the development of the central nervous system. Being a complex hereditary trait, predicting baby's head circumference from parental anthropometrics could complement the already existing ultrasonographic method of prediction. To identify the parental anthropometric determinants of baby's head circumference in Lagos, Nigeria, using a sample of patients attending a government hospital. Parental anthropometric parameters were obtained from 250 couples. The baby's head circumference was measured immediately after birth. The data were subjected to multivariate analysis. The parental variables that were most predictive of babies' head circumference were mid-parental weight, maternal height, maternal weight gain during pregnancy and maternal age. Assessment of these parental attributes can complement ultrasonographic data in predicting baby's head circumference for better perinatal outcome.

Work related stress and coping mechanisms among bankers in Lagos, Nigeria.

PubMed

Olatona, F A; Ezeobika, E N; Okafor, I P; Owoeye, O B A

2014-03-01

This study assessed knowledge, prevalence, associated factors and mechanisms of coping with stress among bankers in Lagos State. It was a descriptive cross sectional study. A two stage sampling technique was used to select two hundred and twenty seven (227) respondents. Data was collected using a structured self administered questionnaire. The analysis was done using Epi-info version 2002 software and Chi Square was used to determine association between variables at p value 0.05. Fischer's Exact test was used where Chi-square was not valid. The age range of respondents was between 20 and 49 years while the mean age was 31.3 +/- 5.0 years. Only 3.6% had good level of knowledge about stress, 42.2% had fair level while more than half of the respondents had poor level of knowledge about stress (54.3%). Majority (67.0%) of the respondents were moderately stressed while one quarter (24.7%) were highly stressed. Majority (92.4%) of the respondents used good coping mechanisms though 69.5% of the respondents also used bad coping mechanisms. A greater proportion of those who had poor knowledge about stress were stressed or highly stressed (p = 0.002). A statistically significant association was also found between the departments in the bank and level of stress of the respondents (p = 0.002). The prevalence of stress was high among the bank workers studied. It is recommended that effective stress management programmes are implemented to address the problem of stress among bank workers.

The possession game? A comparative analysis of ball retention and team success in European and international football, 2007-2010.

PubMed

Collet, Christian

2013-01-01

Possession is thought of as central to success in modern football, but questions remain about its impact on positive team outcomes (Bate, 1988; Hughes & Franks, 2005; Pollard & Reep, 1997; Stanhope, 2001). Recent studies (e.g. Bloomfield, Polman, & O'Donoghue, 2005; Carling, Williams, & Reilly, 2005; James, Mellallieu, & Holley, 2002; Jones, James, & Mellalieu, 2004; Lago, 2009; Lago & Martin, 2007; Lago-Peñas & Dellal, 2010; Lago-Peñas, Lago-Ballesteros, Dellal, & Gómez, 2010; Taylor, Mellalieu, & James, 2005; Tucker, Mellalieu, James, & Taylor, 2005) that have examined these questions have often been constrained by an exclusive focus on English or Spanish domestic play. Using data from five European leagues, UEFA and FIFA tournaments, the study found that while possession time and passing predicted aggregated team success in domestic league play, both variables were poor predictors at the individual match level once team quality and home advantage were accounted for. In league play, the effect of greater possession was consistently negative; in the Champions League, it had virtually no impact. In national team tournaments, possession failed to reach significance when offensive factors were accounted for. Much of the success behind the 'possession game' was thus a function of elite teams confined in geographic and competitive space. That ball hegemony was not consistently tied to success suggests that a nuanced approach to possession is needed to account for variant strategic environments (e.g. James et al., 2002) and compels match analysts to re-examine the metric's overall value.

Discos de acresção em sistemas Be-X

NASA Astrophysics Data System (ADS)

Lopes de Oliveira, R.; Janot-Pacheco, E.

2003-08-01

Alguns fenômenos de outbursts em Be-X sugerem a existência, mesmo que temporária, de um disco de acresção quando da passagem do objeto compacto pelo periastro orbital. Neste trabalho avaliamos a possibilidade de formação do disco de acresção em sistemas Be+estrela de neutrons e Be+anã branca, e a influência da excentricidade orbital na ocorrência deste fenômeno. Utilizamos a expressão analítica para o momento angular específico da matéria constituinte de um meio em expansão lenta, como é o caso do disco circunstelar das estrelas Be, proposta por Wang(1981), sob a condição básica de que o raio de circularização deva ser maior do que o raio de Alfvén. Concluímos que existe um limite para o período orbital do sistema acima do qual não é possível a formação do disco de acresção, e que este valor aumenta para sistemas com excentricidade orbital maior.

Profix cemented total knee replacement: a 5-year outcome review from Lagos, Nigeria.

PubMed

Ugbeye, M E; Odunubi, O O; Dim, E M; Ekundayo, O O

2012-01-01

Total knee replacement is a standard treatment for severe osteoarthritis of the knees. It is however, still a novel procedure in Nigeria. Literature on the procedure and outcome of management are sparse in Nigeria. This study aimed at describing Total Knee prosthetic Replacement as it is practiced in National Orthopaedic Hospital, Lagos. Data on patients treated with Total knee replacement between 2006 and 2010 were analyzed retrospectively. The standard anterior approach, with a medial parapatellar incision under pneumatic tourniquet was used in all cases. There were a total of 59 knees in 48 patients operated, with a female: male ratio of 5:1. Patients were in the sixth to ninth decades of life. There was a statistically significant relationship between duration of symptoms and severity of angular deformity. The average pre-operative Knee score (KS) was 27 and average function score (FS) was 43. Average duration of surgery was 126.38 minutes. Tourniquet removal after wound closure was associated with reduced intra-operative blood loss (p < 0.05). Post-operative complications included peri-prosthetic fracture (1.69%), post-operative anaemia (8.47%), superficial wound dehiscence (3.39%) and foot drop (3.39%). The mean post-operative KS and FS increased to 80 and 75 respectively. Total knee replacement, though a novel procedure in our institution is beneficial to patients with severe osteoarthritis. A long term outcome study is being planned.

Lake-level stratigraphy and geochronology revisited at Lago (Lake) Cardiel, Argentina, and changes in the Southern Hemispheric Westerlies over the last 25 ka

NASA Astrophysics Data System (ADS)

Quade, J.; Kaplan, M. R.

2017-12-01

Paleoshorelines around Lago (Lake) Cardiel in southern Argentina (S48.9°, W71.3°; ∼275 m) record substantial changes in lake area over the past 25 ka. Our results combined with previous research show that during the last glacial maximum (or LGM, 23-21 ka), the lake stood at near modern levels, but had nearly dried up by ∼13 ka. Between 11.3 and 10.1 ka the lake reached its highest point (+54-58 m) and greatest extent in at least the last 40 ka. Lake levels dropped thereafter and experienced two lower-lake periods: 8.5-7.5 ka and 5-3.3 ka; and two higher-lake periods: 7.4-6 and ∼5.2 ka. In the last 3.5 ka, the lake has remained generally near or slightly above its present level. The depth and surface area of Lago Cardiel are controlled mainly by precipitation onto the lake and surrounding catchment, air and water temperature, and wind-speed related to local strength of the Southern Hemispheric Westerlies (SHW). Our lake-level reconstruction combined with evidence from other studies suggest that on average the core of the SHW was located well to the north (<45°S) of the Cardiel basin during the deep lake phase associated with the LGM, and was well to the south (>55°S?) during the hydrologic maximum of Cardiel in the early Holocene. The lower phases of the lake at 20.0-11.5, 8.5-7.5, and 5.0-3.3 ka generally correspond to cold conditions in other records, when we infer that the SHW were strongly focused around the latitudes of Cardiel at 49°S.

Prevalence of cardiovascular risk factors amongst traders in an urban market in Lagos, Nigeria.

PubMed

Odugbemi, T O; Onajole, A T; Osibogun, A O

2012-03-01

A descriptive cross-sectional study was carried out to determine the prevalence of cardiovascular risk factors amongst traders in an urban market in Lagos State. Tejuosho market, one of the large popular markets was selected from a list of markets that met the inclusion criteria of being major markets dealing in general goods using a simple random sampling technique by balloting. Four hundred (400) traders were selected using a systematic random sampling. Each trader was interviewed with a well-structured questionnaire and had blood pressure and anthropometric measurements (height, weight and body mass index). Female traders made up (74.3%) 297 of the total population. The mean age was 45.48+11.88 and 42.29+10.96 years for males and females respectively. Majority 239 (59.8%) fell within the age range of 35 - 55 years. The cardiovascular risk factors identified and their prevalence rates were hypertension (34.8%), physical inactivity (92%), previously diagnosed diabetes mellitus (0.8%), risky alcohol consumption (1%), cigarette smoking (0.3%) in females and (17.5%) in males, obesity (12.3%) and overweight (39.9%). The study recommended that any health promoting, preventive or intervention programme for this population would have to be worked into their market activities if it is to make an impact.

Extensión del Formalismo de Orbitales de Defecto Cuántico al tratamiento del efecto Stark (SQDO).

NASA Astrophysics Data System (ADS)

Menéndez, J. M.; Martín, I.; Velasco, A. M.

El estudio experimental de las interacciones de átomos Rydberg altamente excitados con campos eléctricos ha experimentado un creciente interés durante las dos últimas décadas debido, en gran medida, al desarrollo de nuevas técnicas para crear y estudiar átomos Rydberg en el laboratorio. Acompañando a estas nuevas técnicas experimentales, es necesario el desarrollo de modelos teóricos que nos permitan contrastar sus medidas y conocer mejor los fundamentos de los mismos. Desde el punto de vista teórico el conocimiento del desdoblamiento de los niveles energéticos de un átomo en función de la magnitud del campo eléctrico aplicado (lo que se conoce como mapa Stark) es el mejor punto de partida para la descripción del sistema y un prerrequisito fundamental para el cálculo de distintas propiedades atómicas en presencia del campo eléctrico tales como intensidades de transición, umbrales de ionización de campo eléctrico, tiempos de vida, posición y anchura de cruces evitados, etc. En este trabajo presentamos la adaptación del método de orbitales de defecto cuántico [1,2,3] al tratamiento del efecto Stark (SQDO) [4] y su aplicación al cálculo de los desdoblamientos energéticos y fuerzas de oscilador de estados Rydberg en los átomos de Li, Na y K. El propósito de este estudio es, por un lado, desarrollar métodos fiables para la determinación de propiedades atómicas en presencia de campos eléctricos y, por otro, mostrar la fiabilidad de las funciones de onda QDO en la descripción del efecto Stark en sistemas atómicos.

A study on job satisfaction among clinical and non-clinical hospital staff in a teaching hospital in Lagos, Nigeria.

PubMed

Coker, O O; Coker, A O; Onuoha, B

2011-12-01

Previous studies had demonstrated that continuous and effective productivity of hospital staff are linked to job satisfaction and only those who are satisfied with their job can be maximally effective and productive. This cross-sectional descriptive survey was designed to determine the levels of job satisfaction among various groups of health care professionals working in a teaching hospital in Lagos, Nigeria. Two hundred clinical and non-clinical hospital staff were invited to take part in the study. They completed a sociodemographic questionnaire and the Job Descriptive Index (JDI). The results indicated that majority clinical and non-clinical staff were satisfied with their jobs as regards the parameters of the JDI compared with those not satisfied with their jobs. The government and health policy makers should continue to pay attention to boost job morale and satisfaction of medical health workers to continue to make them to be satisfied with their job.

Late Holocene environmental changes recorded in the sediments of Lago Thompson, Northern Chilean Patagonia

NASA Astrophysics Data System (ADS)

Fagel, Nathalie; Nuttin, Laurence; Bertrand, Sébastien; Borgniet, Geoffrey; Schmidt, Sabine; Araneda, Alberto; Torrejon, Fernando; Urrutia, Roberto

2010-05-01

We investigate the sedimentary record of Lago Thompson, a small lake (area 1.1 km2, watershed ~8 km2) located at an elevation of 750 masl in Northern Chilean Patagonia (45.38 °S, 71.47°W). At Present, the climate conditions around the lake are relatively dry, with annual precipitation averaging 500 mm. The goal of this study is to evaluate the natural climate variability over the Last Millennium in Northern Chilean Patagonia and its impact on the environment. The coring site was selected after a bathymetric survey using an echo-sounder. Several short cores were retrieved in 2008 using an Uwitec gravity corer: the length of the cores ranges between 124 and 132 cm. The preliminary age model is based on 4 AMS radiocarbon ages measured on bulk sediment and organic macro-remains. The radiocarbon ages demonstrate that the sediment cores cover the last 850 to 950 years. This sediment record, which is characterized by accumulation rates ranging between 1 and 3 mm/yr, can therefore be studied at decennial to centennial resolution. To reconstruct past changes in climate and the environment, we conducted a multiproxy study combining sedimentological, mineralogical and geochemical analyses (LOI 105, 550 and 950°C, biogenic silica content, magnetic susceptibility, tephrostratigraphy, bulk organic geochemistry, bulk mineralogy by X-ray diffraction, and inorganic geochemistry by ITRAX core scanner and ICP-AES). Visual descriptions and X-ray radiographies demonstrate that the sediment record is relatively undisturbed. The sediment is composed of light brown organic-rich clayey material. The lower part of the core (below 75 cm) is finely laminated whereas the upper part is more homogeneous. Magnetic susceptibility values highlight two tephra layers that represent explosive eruptions of volcanoes from the southern volcanic zone of Chile (Hudson, Cay, or Macá volcanoes). The biogenic silica content of the sediment retrieved in Lago Thompson is high (40 to 80%), and probably

Psychosocial effects of cleft lip and palate on Nigerians: the Ikeja-Lagos experience.

PubMed

Fadeyibi, Idowu O; Coker, Olurotimi A; Zacchariah, Matthiew P; Fasawe, Adedolapo; Ademiluyi, Samuel A

2012-02-01

We studied 116 patients who presented with cleft lip and palate (CLP) and were seen during a state-wide screening exercise for people with orofacial deformities in Ikeja-Lagos, Nigeria between May 2006 and July 2007. Detailed histories were taken and physical examinations made. The following psychometric instruments: General Health Questionnaire 28 (GHQ28), State-Trait Anxiety Inventory Y1 (STAI-Y1), STAI-Y2, and Self rating Depression Scale (SDS) were given on the respondents by a clinical psychologist. The respondents comprised 57 men and 59 women with a male:female ratio of 1:1.04. There were 42 (36%) adults and 74 (64%) children. Fifty-four (47%) patients had cleft lip (CL), 27 (23%) had cleft lip and palate (CLP), and 35 (30%) had cleft palate alone. Forty-five (39%) of the respondents were parents and guardians who responded to the presence of the deformity on behalf of children who were less than 6 years old, and assessed the reactions of those who were aged 6-12 years old. Older patients replied directly to the psychometric instruments. The outcome of the assessment of the Mental Health Profile of the participants showed high incidence of anxiety, depression, and impairment of general wellbeing. The effects were most pronounced in the 6-12 year age group. We recommend that the psychosocial impacts of CLP on the patients, parents, and relations should be managed together with the reconstructive procedures.

Occupational hazards and safety measures amongst the paint factory workers in lagos, Nigeria.

PubMed

Awodele, Olufunsho; Popoola, Temidayo D; Ogbudu, Bawo S; Akinyede, Akin; Coker, Herbert A B; Akintonwa, Alade

2014-06-01

The manufacture of paint involves a variety of processes that present with medical hazards. Safety initiatives are hence introduced to limit hazard exposures and promote workplace safety. This aim of this study is to assess the use of available control measures/initiatives in selected paint factories in Lagos West Senatorial District, Nigeria. A total of 400 randomly selected paint factory workers were involved in the study. A well-structured World Health Organization standard questionnaire was designed and distributed to the workers to elicit information on awareness to occupational hazards, use of personal protective devices, and commonly experienced adverse symptoms. Urine samples were obtained from 50 workers randomly selected from these 400 participants, and the concentrations of the heavy metals (lead, cadmium, arsenic, and chromium) were determined using atomic absorption spectroscopy. The results show that 72.5% of the respondents are aware of the hazards associated with their jobs; 30% have had formal training on hazards and safety measures; 40% do not use personal protective devices, and 90% of the respondents reported symptoms relating to hazard exposure. There was a statistically significant (p < 0.05) increase in the mean heavy metal concentrations in the urine samples obtained from paint factory workers as compared with nonfactory workers. The need to develop effective frameworks that will initiate the integration and ensure implementation of safety regulations in paint factories is evident. Where these exist, there is a need to promote adherence to these practice guidelines.

Factors affecting patient satisfaction at the Lagos State University Teaching Hospital Dental Clinic.

PubMed

Adeniyi, A A; Adegbite, K O; Braimoh, M O; Ogunbanjo, B O

2013-03-01

Satisfaction is important in dental care because satisfaction with care alleviates dental anxiety, influences patients' compliance and is an important indicator of quality of care. This study was designed to determine the factors that contribute to satisfaction with dental care among patients attending the Lagos State University (LASUTH) Dental Clinic. Across-sectional, descriptive questionnaire-based survey was conducted among adult patients attending the LASUTH Dental Clinic. The questionnaire, a modification of the Dental Satisfaction Questionnaire (DSQ), contained 19 items on a Likert-pattern scale with scores ranging from 0 to 4. The scores obtained for satisfaction with the dental services ranged from 19 to 75 with a mean of 55.30 +/- 11.55. The majority of respondents (305 or 87.4%) were satisfied with the services received. The items generating the highest and lowest mean satisfaction score were cleanliness/comfort of the facility and cost of services respectively. Long waiting time was the item respondents liked least about the services. There was a statistically significant relationship between the items assessing communication and respondent's gender (p = 0.001). The relationship between the overall satisfaction score and gender (p = 0.233), age category (p = 0.842) and educational status (p = 0.565) were not statistically significant. The results indicate a high level of satisfaction with services provided at the LASUTH Dental Clinic. However, there is need for improvement in communication with patients and reduction in waiting time.

'I don't get this climate stuff!' Making sense of climate change among the corporate middle class in Lagos.

PubMed

Asiyanbi, Adeniyi P

2015-11-01

Public engagement continues to be central to wider efforts to address climate change. This study contributes to public engagement debates by investigating engagement with climate change among an often overlooked group, the corporate middle class in Africa's second largest megacity, Lagos. Combining survey and interviews, I focus analysis on three aspects: awareness, knowledge and concern; role of scientific and social frames in shaping general attitude; and spatial attribution of causes and consequences. The study reveals a universal awareness and high concern about climate change among the respondents, although understanding and perceptions of climate change are significantly socially framed. Social situatedness, more than scientific facts, is the most important definer of overall engagement with climate change. This study thus underscores a nuanced constructionist stance, showing how corporate professionals' 'ways of knowing' climate change is underpinned by a certain co-production between scientific and socio-experiential frames. I highlight implications for research and public engagement with climate change. © The Author(s) 2015.

Radiological risk assessment of cosmic radiation at aviation altitudes (a trip from Houston Intercontinental Airport to Lagos International Airport).

PubMed

Enyinna, Paschal Ikenna

2016-01-01

Radiological risk parameters associated with aircrew members traveling from Houston Intercontinental Airport to Lagos International Airport have been computed using computer software called EPCARD (version 3.2). The mean annual effective dose of radiation was computed to be 2.94 mSv/year. This result is above the standard permissible limit of 1 mSv/year set for the public and pregnant aircrew members but below the limit set for occupationally exposed workers. The Risk of cancer mortality and excess career time cancer risk computed ranged from 3.5 × 10(-5) to 24.5 × 10(-5) (with average of 14.7 × 10(-5)) and 7 × 10(-4) to 49 × 10(-4) (with average of 29.4 × 10(-4)). Passengers and aircrew members should be aware of the extra cosmic radiation doses taken in during flights. All aircraft operators should monitor radiation doses incurred during aviation trips.

Radiological risk assessment of cosmic radiation at aviation altitudes (a trip from Houston Intercontinental Airport to Lagos International Airport)

PubMed Central

Enyinna, Paschal Ikenna

2016-01-01

Radiological risk parameters associated with aircrew members traveling from Houston Intercontinental Airport to Lagos International Airport have been computed using computer software called EPCARD (version 3.2). The mean annual effective dose of radiation was computed to be 2.94 mSv/year. This result is above the standard permissible limit of 1 mSv/year set for the public and pregnant aircrew members but below the limit set for occupationally exposed workers. The Risk of cancer mortality and excess career time cancer risk computed ranged from 3.5 × 10−5 to 24.5 × 10−5 (with average of 14.7 × 10−5) and 7 × 10−4 to 49 × 10−4 (with average of 29.4 × 10−4). Passengers and aircrew members should be aware of the extra cosmic radiation doses taken in during flights. All aircraft operators should monitor radiation doses incurred during aviation trips. PMID:27651568

High-resolution chronology for deglaciation of the Patagonian Ice Sheet at Lago Buenos Aires (46.5°S) revealed through varve chronology and Bayesian age modelling

NASA Astrophysics Data System (ADS)

Bendle, Jacob M.; Palmer, Adrian P.; Thorndycraft, Varyl R.; Matthews, Ian P.

2017-12-01

Glaciolacustrine varves offer the potential to construct continuous, annually-resolved chronologies for ice-sheet deglaciation, and improved understanding of glacier retreat dynamics. This paper investigates laminated glaciolacustrine sediments deposited around the waning margins of the Patagonian Ice Sheet, following the local Last Glacial Maximum (LGM). Detailed macro- and microfacies analyses confirm an annual (varve) structure within these sediments. The correlation of annual layers (varves) across five sites in eastern Lago Buenos Aires yields a 994 ± 36 varve-year (vyr) chronology and thickness record. The floating chronology has been anchored to the calendar-year timescale through identification of the Ho tephra (17,378 ± 118 cal a BP) in the varve sequences. Using a Bayesian age model to integrate the new varve chronology with published moraine ages, the onset of deglaciation at 46.5°S is dated to 18,086 ± 214 cal a BP. New age estimates for deglacial events are combined with high-resolution analysis of varve thickness trends, and new lithostratigraphic data on ice-margin position(s), to reconstruct ice-margin retreat rates for the earliest ca. 1000 years of ice-sheet demise. Glacier retreat rates were moderate (5.3-10.3 m yr-1) until 17,322 ± 115 cal a BP, but subsequently accelerated (15.4-18.0 m yr-1). Sustained influxes of ice-rafted debris (IRD) after 17,145 ± 122 cal a BP suggest retreat rates were enhanced by calving after ice contracted into deeper lake waters. Ice persisted in eastern Lago Buenos Aires until at least 16,934 ± 116 cal a BP, after which the glacier started to retreat towards the Patagonian mountains.

Long-Term Survival of an Urban Fruit Bat Seropositive for Ebola and Lagos Bat Viruses

PubMed Central

Hayman, David T. S.; Emmerich, Petra; Yu, Meng; Wang, Lin-Fa; Suu-Ire, Richard; Fooks, Anthony R.; Cunningham, Andrew A.; Wood, James L. N.

2010-01-01

Ebolaviruses (EBOV) (family Filoviridae) cause viral hemorrhagic fevers in humans and non-human primates when they spill over from their wildlife reservoir hosts with case fatality rates of up to 90%. Fruit bats may act as reservoirs of the Filoviridae. The migratory fruit bat, Eidolon helvum, is common across sub-Saharan Africa and lives in large colonies, often situated in cities. We screened sera from 262 E. helvum using indirect fluorescent tests for antibodies against EBOV subtype Zaire. We detected a seropositive bat from Accra, Ghana, and confirmed this using western blot analysis. The bat was also seropositive for Lagos bat virus, a Lyssavirus, by virus neutralization test. The bat was fitted with a radio transmitter and was last detected in Accra 13 months after release post-sampling, demonstrating long-term survival. Antibodies to filoviruses have not been previously demonstrated in E. helvum. Radio-telemetry data demonstrates long-term survival of an individual bat following exposure to viruses of families that can be highly pathogenic to other mammal species. Because E. helvum typically lives in large urban colonies and is a source of bushmeat in some regions, further studies should determine if this species forms a reservoir for EBOV from which spillover infections into the human population may occur. PMID:20694141

Long-term survival of an urban fruit bat seropositive for Ebola and Lagos bat viruses.

PubMed

Hayman, David T S; Emmerich, Petra; Yu, Meng; Wang, Lin-Fa; Suu-Ire, Richard; Fooks, Anthony R; Cunningham, Andrew A; Wood, James L N

2010-08-04

Ebolaviruses (EBOV) (family Filoviridae) cause viral hemorrhagic fevers in humans and non-human primates when they spill over from their wildlife reservoir hosts with case fatality rates of up to 90%. Fruit bats may act as reservoirs of the Filoviridae. The migratory fruit bat, Eidolon helvum, is common across sub-Saharan Africa and lives in large colonies, often situated in cities. We screened sera from 262 E. helvum using indirect fluorescent tests for antibodies against EBOV subtype Zaire. We detected a seropositive bat from Accra, Ghana, and confirmed this using western blot analysis. The bat was also seropositive for Lagos bat virus, a Lyssavirus, by virus neutralization test. The bat was fitted with a radio transmitter and was last detected in Accra 13 months after release post-sampling, demonstrating long-term survival. Antibodies to filoviruses have not been previously demonstrated in E. helvum. Radio-telemetry data demonstrates long-term survival of an individual bat following exposure to viruses of families that can be highly pathogenic to other mammal species. Because E. helvum typically lives in large urban colonies and is a source of bushmeat in some regions, further studies should determine if this species forms a reservoir for EBOV from which spillover infections into the human population may occur.

The effect of a sexuality education programme among out- of- school adolescents in Lagos, Nigeria.

PubMed

Odeyemi, K A; Onajole, A T; Ogunowo, B E; Olufunlayo, T; Segun, B

2014-06-01

This study was conducted to assess the effect of a community based sexuality education programme on the sexual health knowledge and practices of out of school female adolescents. This Intervention study was conducted in two markets within Lagos, Nigeria. Representative samples of adolescents were interviewed on their sexual health knowledge and practices. An Education- entertainment programme provided sexuality education to adolescents in Mushin market only (intervention group) followed by post intervention surveys in Mushin market and Sangrouse market (control group). The pre and post intervention surveys were compared 6 months post intervention to detect any changes. Sexual health knowledge and behaviour was similar among respondents in both markets pre intervention. Post intervention, the sexual health knowledge of the respondents in the intervention site improved significantly. (p<0.05) Fewer adolescents initiated sex in the intervention site than in the control site and contraceptive use increased. However among the sexually active, there was no significant change in their condom use and number of sexual partners. Community based health education programmes can be used to provide effective sexuality education for out of school adolescents. Provision should be made by government and non-governmental organisations during adolescent reproductive health programming for sexuality education targeted at out of school adolescents.

The duration of prograde garnet crystallization in the UHP eclogites at Lago di Cignana, Italy

NASA Astrophysics Data System (ADS)

Skora, Susanne; Lapen, Thomas J.; Baumgartner, Lukas P.; Johnson, Clark M.; Hellebrand, Eric; Mahlen, Nancy J.

2009-10-01

The distinct core-to-rim zonation of different REEs in garnet in metamorphic rocks, specifically Sm relative to Lu, suggests that Sm-Nd and Lu-Hf isochron ages will record different times along a prograde garnet growth history. Therefore, REE zonations in garnet must be measured in order to correctly interpret the isochron ages in terms of the garnet growth interval, which could span several m.y. New REE profiles, garnet crystal size distributions, and garnet growth modeling, combined with previously published Sm-Nd and Lu-Hf geochronology on a UHP eclogite of the Zermatt-Saas Fee (ZSF) ophiolite, Lago di Cignana (Italy), demonstrate that prograde garnet growth of this sample occurred over a ~ 30 to 40 m.y. interval. Relative to peak metamorphism at 38 to 40 Ma, garnet growth is estimated to have begun at ~ 11 to 14 kbar pressure at ~ 70 to 80 Ma. Although such a protracted garnet growth interval is surprising, this is supported by plate tectonic reconstructions which suggest that subduction of the Liguro-Piemont ocean occurred through slow and oblique convergence. These results demonstrate that REE zonations in garnet, coupled to crystal size distributions, provide a powerful means for understanding prograde metamorphic paths when combined with Sm-Nd and Lu-Hf geochronology.

Prevalence and correlates of depressive disorders in outpatients with breast cancer in Lagos, Nigeria.

PubMed

Popoola, Abiodun O; Adewuya, Abiodun O

2012-06-01

While the physical complications of breast cancer are often recognized and well managed, the psychological sequelae, especially depression are often unrecognized by healthcare providers and therefore under treated. This study aimed to assess the rate and correlate of depressive disorders in breast cancer survivors in Lagos, Nigeria. Patients (n = 124) recruited from a breast cancer outpatient clinic were assessed for the DSM-IV diagnosis of depressive disorders using the Mini International Neuropsychiatric Interview (MINI). The staging of the cancer, length of diagnosis and treatment type were recorded. Also socio-demographic details and their perceived level of social support were obtained. Twenty-one (16.9%) were diagnosed as having Major Depressive Disorder, while 29 (23.4%) had Minor depressive disorder making a total of 50 (40.3%) cases with depression. The independent correlates of depression included being not married (odds ratio (OR) 3.09, 95% CI 1.30-7.42), perceived poor social support (OR 5.38, 95% CI 1.88-16.63) and advanced stage of the cancer (OR 3.22, 95% CI 1.32-8.26). Our study suggests a high rate of associated depression among patients with breast cancer in our environment. Clinicians should be encouraged and empowered to probe for symptoms of depression in these patient while larger hypothesis-driven studies are needed. Copyright © 2011 John Wiley & Sons, Ltd.

Bearded saki feeding strategies on an island in Lago Guri, Venezuela.

PubMed

Norconk, Marilyn A; Conklin-Brittain, Nancy L

2016-05-01

Free-ranging bearded sakis (Chiropotes spp.) live in relatively large social groups (22-65+), inhabit very large home ranges (200-1,000 ha), and travel long distances (1.8 to >7 km) each day. While these characteristics would seem to reduce their ability to occupy habitat fragments, several studies suggest otherwise. The key to their success may lie in their dietary adaptations. Bearded sakis are strongly frugivorous, but are primarily seed eaters, and are able to ingest both young and mature fruit. We examined feeding activities of a group of bearded sakis over a 19-month period on a 180 ha island in Lago Guri, Venezuela. Given their feeding adaptations, we predicted that they would minimize peaks and troughs in plant species used for food, limit seasonal variation in the mechanical properties of foods ingested, and balance ingestion of energy-rich foods (e.g. lipids, nonstructural carbohydrates (TNC), and/or free simple sugars). We found that bearded sakis on Danto Manchado had a diverse (plant-based) diet, but two resources (Pradosia caracasana, Sapotaceae, and Oryctanthus alveolatus, Loranthaceae) provided a stable dietary base and were present in the diet almost every month. Second, we found little variation in the mechanical-resistance properties of fruits opened seasonally. Third, they alternated months ingesting foods with high TNC content and months of high lipid content. This may be an attempt to balance energy intake from available foods. Finally, their social propensity to split up into subgroups may predispose them to reduce group sizes to accommodate smaller available areas. We suggest that bearded sakis use both ecological and behavioral mechanisms to survive in smaller-than-typical areas. Longer-term studies (beyond a few generations) of bearded sakis in habitat fragments would allow us to estimate minimum survival area and identify critical resources or resource combinations. © 2015 Wiley Periodicals, Inc.

Head circumference of children with sickle cell disease in Lagos, Nigeria.

PubMed

Senbanjo, Idowu Odunayo; Oshikoya, Kazeem Adeola; Salisu, Mohammed; Diaku-Akinwumi, Ijeoma Nnenna

2016-01-01

Growth retardation and under-nutrition are common in children with sickle cell disease (SCD). The aim of this study was to compare the head circumference (HC) of SCD children and non-SCD children and to determine the effect of malnutrition on head circumference of children with SCD. This was a prospective case-control study conducted at the Lagos State University Teaching Hospital, Nigeria, involving SCD children (subject, n = 118) and non-SCD children (control, n = 118) matched for age, sex, and socioeconomic status. Weight, height and HC were measured using standard techniques. The mean ages of children with and without SCD were 7.46 ± 3.69 years and 7.01 ± 3.58 years, respectively. The HC increased significantly with age in both males and females (r = 0.75, p = < 0.001; r = 0.70, p < 0.001 respectively). There was no significant difference in HC between males and females (p > 0.05). At all ages, the mean head circumference of SCD children was not significantly (p > 0.05) different from non-SCD children. The In the age group 11-15 years, the prevalence of stunting was significantly higher among SCD children than non-SCD children. The mean HC of SCD children with stunting was significantly lower than those not stunted (51.7 vs. 53.5; P= 0.006) in age group 11.15 years. The head circumference of children with SCD is not significantly different from that of non-SCD children. Therefore, the HC chart for the general population is also applicable for monitoring head growth in children with SCD. The effect of malnutrition on head circumference of SCD children is most marked in age group 11-15 years.

Head circumference of children with sickle cell disease in Lagos, Nigeria

PubMed Central

Senbanjo, Idowu Odunayo; Oshikoya, Kazeem Adeola; Salisu, Mohammed; Diaku-Akinwumi, Ijeoma Nnenna

2016-01-01

Introduction Growth retardation and under-nutrition are common in children with sickle cell disease (SCD). The aim of this study was to compare the head circumference (HC) of SCD children and non-SCD children and to determine the effect of malnutrition on head circumference of children with SCD. Methods This was a prospective case-control study conducted at the Lagos State University Teaching Hospital, Nigeria, involving SCD children (subject, n = 118) and non-SCD children (control, n = 118) matched for age, sex, and socioeconomic status. Weight, height and HC were measured using standard techniques. Results The mean ages of children with and without SCD were 7.46 ± 3.69 years and 7.01 ± 3.58 years, respectively. The HC increased significantly with age in both males and females (r = 0.75, p = < 0.001; r = 0.70, p < 0.001 respectively). There was no significant difference in HC between males and females (p > 0.05). At all ages, the mean head circumference of SCD children was not significantly (p > 0.05) different from non-SCD children. The In the age group 11-15 years, the prevalence of stunting was significantly higher among SCD children than non-SCD children. The mean HC of SCD children with stunting was significantly lower than those not stunted (51.7 vs. 53.5; P= 0.006) in age group 11.15 years. Conclusion The head circumference of children with SCD is not significantly different from that of non-SCD children. Therefore, the HC chart for the general population is also applicable for monitoring head growth in children with SCD. The effect of malnutrition on head circumference of SCD children is most marked in age group 11-15 years. PMID:28154697

Things to Remember about El Sistema: A Response to "El Sistema--A Perspective for North American Music Educators" by Tricia Tunstall

ERIC Educational Resources Information Center

Lesniak, Melissa

2013-01-01

Melissa Lesniak, the executive director of the Greater Miami Youth Symphony, discusses how much she enjoyed reading the responses to her "El Sistema" article and appreciates the opportunity for healthy dialogue and debate. In response, she states that there are many common goals and objectives across all music education programs that can…

Pathogenesis of bat rabies in a natural reservoir: Comparative susceptibility of the straw-colored fruit bat (Eidolon helvum) to three strains of Lagos bat virus.

PubMed

Suu-Ire, Richard; Begeman, Lineke; Banyard, Ashley C; Breed, Andrew C; Drosten, Christian; Eggerbauer, Elisa; Freuling, Conrad M; Gibson, Louise; Goharriz, Hooman; Horton, Daniel L; Jennings, Daisy; Kuzmin, Ivan V; Marston, Denise; Ntiamoa-Baidu, Yaa; Riesle Sbarbaro, Silke; Selden, David; Wise, Emma L; Kuiken, Thijs; Fooks, Anthony R; Müller, Thomas; Wood, James L N; Cunningham, Andrew A

2018-03-01

Rabies is a fatal neurologic disease caused by lyssavirus infection. People are infected through contact with infected animals. The relative increase of human rabies acquired from bats calls for a better understanding of lyssavirus infections in their natural hosts. So far, there is no experimental model that mimics natural lyssavirus infection in the reservoir bat species. Lagos bat virus is a lyssavirus that is endemic in straw-colored fruit bats (Eidolon helvum) in Africa. Here we compared the susceptibility of these bats to three strains of Lagos bat virus (from Senegal, Nigeria, and Ghana) by intracranial inoculation. To allow comparison between strains, we ensured the same titer of virus was inoculated in the same location of the brain of each bat. All bats (n = 3 per strain) were infected, and developed neurological signs, and fatal meningoencephalitis with lyssavirus antigen expression in neurons. There were three main differences among the groups. First, time to death was substantially shorter in the Senegal and Ghana groups (4 to 6 days) than in the Nigeria group (8 days). Second, each virus strain produced a distinct clinical syndrome. Third, the spread of virus to peripheral tissues, tested by hemi-nested reverse transcriptase PCR, was frequent (3 of 3 bats) and widespread (8 to 10 tissues positive of 11 tissues examined) in the Ghana group, was frequent and less widespread in the Senegal group (3/3 bats, 3 to 6 tissues positive), and was rare and restricted in the Nigeria group (1/3 bats, 2 tissues positive). Centrifugal spread of virus from brain to tissue of excretion in the oral cavity is required to enable lyssavirus transmission. Therefore, the Senegal and Ghana strains seem most suitable for further pathogenesis, and for transmission, studies in the straw-colored fruit bat.

Pathogenesis of bat rabies in a natural reservoir: Comparative susceptibility of the straw-colored fruit bat (Eidolon helvum) to three strains of Lagos bat virus

PubMed Central

Suu-Ire, Richard; Banyard, Ashley C.; Breed, Andrew C.; Drosten, Christian; Eggerbauer, Elisa; Freuling, Conrad M.; Gibson, Louise; Goharriz, Hooman; Horton, Daniel L.; Jennings, Daisy; Kuzmin, Ivan V.; Marston, Denise; Ntiamoa-Baidu, Yaa; Riesle Sbarbaro, Silke; Selden, David; Wise, Emma L.; Kuiken, Thijs; Fooks, Anthony R.; Müller, Thomas; Wood, James L. N.; Cunningham, Andrew A.

2018-01-01

Rabies is a fatal neurologic disease caused by lyssavirus infection. People are infected through contact with infected animals. The relative increase of human rabies acquired from bats calls for a better understanding of lyssavirus infections in their natural hosts. So far, there is no experimental model that mimics natural lyssavirus infection in the reservoir bat species. Lagos bat virus is a lyssavirus that is endemic in straw-colored fruit bats (Eidolon helvum) in Africa. Here we compared the susceptibility of these bats to three strains of Lagos bat virus (from Senegal, Nigeria, and Ghana) by intracranial inoculation. To allow comparison between strains, we ensured the same titer of virus was inoculated in the same location of the brain of each bat. All bats (n = 3 per strain) were infected, and developed neurological signs, and fatal meningoencephalitis with lyssavirus antigen expression in neurons. There were three main differences among the groups. First, time to death was substantially shorter in the Senegal and Ghana groups (4 to 6 days) than in the Nigeria group (8 days). Second, each virus strain produced a distinct clinical syndrome. Third, the spread of virus to peripheral tissues, tested by hemi-nested reverse transcriptase PCR, was frequent (3 of 3 bats) and widespread (8 to 10 tissues positive of 11 tissues examined) in the Ghana group, was frequent and less widespread in the Senegal group (3/3 bats, 3 to 6 tissues positive), and was rare and restricted in the Nigeria group (1/3 bats, 2 tissues positive). Centrifugal spread of virus from brain to tissue of excretion in the oral cavity is required to enable lyssavirus transmission. Therefore, the Senegal and Ghana strains seem most suitable for further pathogenesis, and for transmission, studies in the straw-colored fruit bat. PMID:29505617

Music Pedagogy as an Aid to Integration? El Sistema-Inspired Music Activity in Two Swedish Preschools

ERIC Educational Resources Information Center

Gustavsson, Hans-Olof; Ehrlin, Anna

2018-01-01

The study focuses on how preschool and musical school teachers experience working with El Sistema-inspired activity at two municipal preschools in a multicultural district in a medium-sized Swedish town. What, according to the educators,is the most significant aspect of working with El Sistema-inspired activities? The theoretical point of…

Use and Effects of Malaria Control Measures in Pregnancy in Lagos, Nigeria

PubMed Central

Amoo, A. O. J.; Akintunde, Grace B.; Ojelekan, Oluwole D.; König, Wolfgang; König, Brigitte

2011-01-01

In Nigeria, malaria causes up to 11% of maternal mortality. Our main aim was to find out the most common mosquito control measures employed by the pregnant women in Lagos and their effects on malaria infection. The study was carried out over a period of 6 months during which trained interviewers administered questionnaires to 400 pregnant women. The prevalence of malaria was 8.4%. There was no significant association between the prevalence of malaria and age, level of education, or occupation of the participants. Pregnant women in the age range 26-30 had the mean parasite density (409.9±196.80). Insecticide spray (32.8%), mosquito coil (27.5%), and insecticide-treated nets (ITN) (15.5%) were the major mosquito control measures employed by the participants while the prevalence of infection among them were 2.3%, 6.2%, and 3.2%, respectively (P<0.05). Only 18.3% of the women had taken more than one dose of intermittent preventive treatment (IPT), while another 11.8% had taken a single dose. The infection rate among them was 4.1% and 6.4%, respectively. Malaria prevalence was highest among those who had not received any dose of IPT (10%). This study showed that the use of ITN and IPT among the pregnant women were still unacceptably low. It also showed that the use of insecticide spray which was the most common malaria control measure adopted by the participants was effective despite the fact that it is not a National Malaria Control Policy. We recommend that a sustained integrated mosquito management and public education should be strengthened in Nigeria. PMID:22355203

Determination of the total level of nitrosamines in select consumer products in Lagos area of Nigeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coker, H.A.B.; Thomas, A.E.; Akintonwa, A.

1991-11-01

For some time there has been a considerable interest and growing concern in the extent of contamination of food items by N-nitrosamines because of the known carcinogenicity and mutagenicity of these compounds. Nitrosamines can be derived from the interaction of organic secondary and tertiary amines with nitrite, nitrate under reducing conditions, low pH values or nitrous gases. In Nigeria, the present harsh economic conditions have somewhat influenced the emergence of different kinds of socioeconomic attitude in Nigerians. There is now high incidence of adulteration of many consumer products. Faking of assorted consumables and pharmaceuticals, notably drugs, is a common feature,more » all in attempt to cut corners. It is a common practice amongst the local people to use certain chemicals as preservatives, colorants and flavorants without taking cognizance of the long-term health and toxicological hazards posed to the citizenry by these foreign agents. Recent work in the authors' laboratory had shown the presence of N-nitrosamines in some consumer products and it was therefore thought that a more thorough investigation and survey of as many foods and drinks as possible in the Lagos metropolis for contamination by nitrosamines might present a more revealing picture.« less

A survey of operational characteristics, socioeconomic and health effects of scavenging activity in Lagos, Nigeria.

PubMed

Afon, Abel

2012-07-01

This study presents the social, economic, health and environmental implications of solid waste scavenging activity in Olusosun, one of the government's designated open waste dumpsites in Lagos, Nigeria. Using incidental or convenience sampling methods of questionnaire administration, 112 scavengers were sampled. It was established that scavenging on the site was only possible through registration with an associate on site. Recovering items from hills of waste involved physical energy and the use of manually-operated rudimentary equipment. Thus, 87% of the scavengers were males in their early twenties (minimum age = 19 years; maximum age = 35 years; mean = 26.7 years; SD = 4.2). The daily mean income from the exercise was Naira 480.80 (Naira 160 = $1.00). The most important method of arriving at the selling prices of the scavenged products was the use of scale measurement. Although the scavengers were aware that scavenging exposed them to both environmental and health hazards, they continued scavenging for economic and social reasons. The study concluded that because of the level of employment provided and the large number of people directly involved (1243 on this site alone), outright banning, even when the open dump is closed down, without rehabilitating the scavengers will constitute a social, economic and security threat to the community. Scavenging should, therefore, be integrated fully into the waste-management system and regulated.

Solid waste generation and characterization in the University of Lagos for a sustainable waste management.

PubMed

Adeniran, A E; Nubi, A T; Adelopo, A O

2017-09-01

Waste characterization is the first step to any successful waste management policy. In this paper, the characterization and the trend of solid waste generated in University of Lagos, Nigeria was carried out using ASTM D5231-92 and Resource Conservation Reservation Authority RCRA Waste Sampling Draft Technical Guidance methods. The recyclable potential of the waste is very high constituting about 75% of the total waste generated. The estimated average daily solid waste generation in Unilag Akoka campus was estimated to be 32.2tons. The solid waste characterization was found to be: polythene bags 24% (7.73tons/day), paper 15% (4.83tons/day), organic matters 15%, (4.83tons/day), plastic 9% (2.90tons/day), inert materials 8% (2.58tons/day), sanitary 7% (2.25tons/day), textile 7% (2.25tons/day), others 6% (1.93tons/day), leather 4% (1.29tons/day) metals 3% (0.97tons/day), glass 2% (0.64tons/day) and e-waste 0% (0.0tons/day). The volume and distribution of polythene bags generated on campus had a positive significant statistical correlation with the distribution of commercial and academic structures on campus. Waste management options to optimize reuse, recycling and reduce waste generation were discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental and climatic conditions at a potential Glacial refugial site of tree species near the Southern Alpine glaciers. New insights from multiproxy sedimentary studies at Lago della Costa (Euganean Hills, Northeastern Italy)

NASA Astrophysics Data System (ADS)

Kaltenrieder, Petra; Belis, Claudio A.; Hofstetter, Simone; Ammann, Brigitta; Ravazzi, Cesare; Tinner, Willy

2009-12-01

It has been hypothesized that refugia of thermophilous tree species were located in Northern Italy very close to the Alps, though, this hypothesis has yet to be tested thoroughly. In contrast to Central and Southern Italy with its relative wealth of data, only a few fragmentary records are currently available from Northern Italy for the last Glacial (Würm, Weichselian). Our new study site Lago della Costa lies adjacent to the catchment of the megafans of the Alpine forelands and the braided rivers of the Northeastern Po Plain that have so far inhibited the recovery of continuous Glacial and Late-Glacial records. We analyze pollen, plant macrofossils, charcoal and ostracods to reconstruct the vegetation, fire and lake history for the period 33,000-16,000 cal. BP. We compare our data with Glacial records from Southern Europe to discuss similarities and dissimilarities between these potential refugial areas. A comparison with independent paleoclimatic proxies allows to assess potential linkages between environmental and climatic variability. New macrofossil and pollen data at Lago della Costa unambiguously document the local persistence of boreal tree taxa such as Larix decidua and Betula tree species around the study site during the last Glacial. The regular occurrence of pollen of temperate trees in the organic lake sediments (fine-detritus calcareous gyttja) suggests that temperate taxa such as Corylus avellana, Quercus deciduous, Tilia, Ulmus, Fraxinus excelsior, Carpinus, Abies alba and Fagus sylvatica, most likely survived the Last Glacial Maximum (LGM) at favorable sites in the Euganean Hills. The percentage values of temperate trees are comparable with those from Southern Europe (e.g. Monticchio in Southern Italy). We conclude that the Euganean Hills were one of the northernmost refugial areas of temperate taxa in Europe. However, the relative and absolute abundances of pollen of temperate trees are highly variable. Pollen-inferred declines of temperate tree

The Story of Carora: The Origins of El Sistema

ERIC Educational Resources Information Center

Carlson, Alexandra

2016-01-01

Venezuela's youth symphony program, the Fundación Musical Simón Bolívar, commonly referred to as "El Sistema," combines musical achievement with learning important life skills through orchestral practice and performance. Although the history most commonly reported outside Venezuela is of the program's director, José Antonio Abreu,…

Trace elements and oxidative stress levels in the blood of painters in Lagos, Nigeria: occupational survey and health concern.

PubMed

Awodele, Olufunsho; Akinyede, Akin; Babawale, Omotola Opeyemi; Coker, Herbert A Babatunde; Akintonwa, Alade

2013-06-01

Adverse effects attributed to exposure to paints are currently a concern because of the continued widespread use of paint containing trace elements. Thus, occupational survey amongst painters in Lagos and determination of trace elements and oxidative stress parameters were carried out. Descriptive cross-sectional survey was done using a standardized questionnaire to obtain job safety-related information. Forty-eight percent of the painters were aware of hazards associated with painting and 52 % of these workers were aware of the necessary precautionary measures during painting. There were no significant differences (p ≥ 0.05) between the levels of trace elements in the blood of painters and the control subjects. However, there was a significance increase (p ≤ 0.0001) in the level of malondialdehyde and a decrease (p ≤ 0.001) in the levels of reduced glutathione, superoxide dismutase, and catalase of the painters compared to the control. An increase in oxidative stress parameters may not only be due to trace element concentrations, but also the painters' exposure to some petrochemical solvents during mixing of paints.

Life-stages, exploitation status and habitat use of Lutjanus goreensis (Perciformes: Lutjanidae) in coastal marine environments of Lagos, SW Nigeria.

PubMed

Kafayat, A Fakoya; Martins, A Anetekhai; Shehu, L Akintola; Abdulwakil, O Sabal; Abass, Mikhail A

2015-03-01

The Gorean snapper, Lutanus goreensis is an important component of artisanal fisheries and trawl landings in the Gulf of Guinea. Despite its economic importance, there is a dearth of information on size structure and life history strategies of the species. Therefore, the objectives of this study were to provide baseline data on the life stages, exploitation status and habitat use for the species in Nigeria. Monthly samples were obtained from artisanal and trawl catches in Five Cowrie Creek and Lagos coastal waters between December 2008 and December 2010, respectively. Length-frequency distributions of the fishes caught were analysed to provide preliminary information on mean and modal lengths at capture and life-history strategies based on habitat use and estuarine-dependency for L. goreensis. A total of 822 specimens of L. goreensis were collected from Five Cowrie Creek while 377 specimens were collected from Lagos coastal waters. Total length varied between 7.90-34.90 cm for creek samples and from 21.90-56.10 cm for marine samples. Length-frequency histograms showed polymodal size distributions in creek and marine samples. Length-frequency distributions of L. goreensis showed a high abundance ofjuveniles (<20 cm) and sub-adults (20-35 cm) which accounted for 84.1% and 68.4% of creek and marine samples examined, respectively. For the creek samples, fish in modal length class of 13.00-13.99 cm were the most exploited while in the marine samples, length classes of 29.00-30.99 cm and 31.00-32.99cm constituted the most frequently exploited fishes. Increase in total lengths from the creek (mean +/- SD; 16.19 +/- 3.73 cm) to the marine habitat samples (32.89 +/- 6.14 cm) indicated ontogenetic shift in habitat use. Occurrence of a predominant juvenile population in Five Cowrie Creek by L. goreensis suggests estuarine-dependency and is indicative of a temporary juvenile habitat or a migratory corridor. In conclusion, data from the presently reported study and previous

Tobacco related knowledge and support for smoke-free policies among community pharmacists in Lagos state, Nigeria

PubMed Central

Poluyi, Edward O.; Odukoya, Oluwakemi O.; Aina, Bolajoko; Faseru, Babalola

2014-01-01

Background: There are no safe levels of exposure to second hand smoke and smoke-free policies are effective in reducing the burden of tobacco-related diseases and death. Pharmacists, as a unique group of health professionals, might be able to play a role in the promotion of smoke-free policies. Objective: To determine the tobacco-related knowledge of community pharmacists and assess their support for smoke-free policies in Lagos state, Nigeria. Methods: A cross-sectional descriptive study design using both quantitative and qualitative methods was employed. Two hundred and twelve randomly selected community pharmacists were surveyed using a pre-tested self-administered questionnaire. In addition, one focus group discussion was conducted with ten members of the Lagos state branch of the Association of Community Pharmacists of Nigeria. Results: The quantitative survey revealed that the majority (72.1%) of the respondents were aged between 20 and 40 years, predominantly male (60.8%), Yoruba (50.2%) or Igbo (40.3%) ethnicity and had been practicing pharmacy for ten years or less (72.2%). A majority (90.1%) of respondents were aware that tobacco is harmful to health. Slightly less (75.8%) were aware that second hand smoke is harmful to health. Among the listed diseases, pharmacists responded that lung (84.4%) and esophageal (68.9%) cancers were the most common diseases associated with tobacco use. Less than half of those surveyed associated tobacco use with heart disease (46.9%), chronic obstructive pulmonary disease (27.8%), bladder cancer (47.2%), peripheral vascular disease (35.8%) and sudden death (31.1%). Only 51.9% had heard of the World Health Organization Framework Convention on Tobacco Control (WHO FCTC). A little over half of the respondents (53.8%) were aware of any law in Nigeria controlling tobacco use. The majority of respondents supported a ban on smoking in homes (83.5%), in public places (79.2%), and in restaurants, nightclubs and bars (73.6%). For every

"The Feelings Have Come Home to Me." Examining Advertising Films on the Swedish Website of El Sistema

ERIC Educational Resources Information Center

Kuuse, Anna-Karin; Lindgren, Monica; Skåreus, Eva

2016-01-01

The purpose of this study is to analyze how the music educational program of El Sistema Sweden is advertised and legitimized through moving images. The films are a major part of the information on the Swedish national website of El Sistema and are supposed to contribute to the picture that the organization and its founders wish to market. The use…

Sobre os sistemas de referência celeste

NASA Astrophysics Data System (ADS)

Poppe, P. C. R.; Martin, V. A. F.

2003-02-01

Apresentamos neste trabalho, algumas discussões sobre os sistemas de referência utilizados em Astronomia. Claramente, não é possível esgotar todo este assunto num único texto, mas esperamos, contudo, que o presente material possa ser apreciado nos cursos de Introdução à Astronomia, que estão cada vez mais presentes nas atuais propostas curriculares das graduações de Física. As discussões pertinentes às "Bases de Referência Celeste", serão apresentadas em um outro trabalho.

Prevalence and Factors Associated with Intimate Partner Violence among Married Women in an Urban Community in Lagos State, Nigeria.

PubMed

Onigbogi, Modupe O; Odeyemi, Kofoworola A; Onigbogi, Olanrewaju O

2015-03-01

Violence against women is a major public health problem globally. A cross-sectional descriptive study was conducted in Ikosi Isheri LCDA of Lagos State among 400 married women. A multistage sampling method was used to select the respondents. The lifetime prevalence for physical violence, sexual violence and psychological violence were 50.5%, 33.8% and 85.0% respectively. Predictive factors for physical IPV include lower educational status of the women (AOR 3.22 95% CI: 1.54-6.77) and partner's daily alcohol intake (AOR: 1.84 95% CI: 1.05-3.23). The predictors of sexual violence include unemployment status of the partners (OR 5.89:1.39-24.84) and daily/weekly alcohol use (AOR 1.87 95% CI: 1.05-3.33). Predictors of psychological violence include respondents witness of parental violence (AOR 2.80 95% CI: 1.04-7.5) and daily alcohol use by partners (AOR 2.71 95% CI: 1.19-6.18). Preventive interventions such as increasing the educational status of women and reducing the intake of alcohol by men may help break the cycle of abuse.

Synthesizing (ZrAl3 + AlN)/Mg-Al composites by a 'matrix exchange' method

NASA Astrophysics Data System (ADS)

Gao, Tong; Li, Zengqiang; Hu, Kaiqi; Han, Mengxia; Liu, Xiangfa

2018-06-01

A method named 'matrix exchange' to synthesize ZrAl3 and AlN reinforced Mg-Al composite was developed in this paper. By inserting Al-10ZrN master alloy into Mg matrix and reheating the cooled ingot to 550 °C, Al and Mg atoms diffuse to the opposite side. As a result, liquid melt occurs once the interface areas reach to proper compositions. Then dissolved Al atoms react with ZrN, leading to the in-situ formation of ZrAl3 and AlN particles, while the Al matrix is finally replaced by Mg. This study provides a new insight for preparing Mg composites.

Vibrational Surface Electron-Energy-Loss Spectroscopy Probes Confined Surface-Phonon Modes

NASA Astrophysics Data System (ADS)

Lourenço-Martins, Hugo; Kociak, Mathieu

2017-10-01

Recently, two reports [Krivanek et al. Nature (London) 514, 209 (2014), 10.1038/nature13870, Lagos et al. Nature (London) 543, 529 (2017), 10.1038/nature21699] have demonstrated the amazing possibility to probe vibrational excitations from nanoparticles with a spatial resolution much smaller than the corresponding free-space phonon wavelength using electron-energy-loss spectroscopy (EELS). While Lagos et al. evidenced a strong spatial and spectral modulation of the EELS signal over a nanoparticle, Krivanek et al. did not. Here, we show that discrepancies among different EELS experiments as well as their relation to optical near- and far-field optical experiments [Dai et al. Science 343, 1125 (2014), 10.1126/science.1246833] can be understood by introducing the concept of confined bright and dark surface phonon modes, whose density of states is probed by EELS. Such a concise formalism is the vibrational counterpart of the broadly used formalism for localized surface plasmons [Ouyang and Isaacson Philos. Mag. B 60, 481 (1989), 10.1080/13642818908205921, García de Abajo and Aizpurua Phys. Rev. B 56, 15873 (1997), 10.1103/PhysRevB.56.15873, García de Abajo and Kociak Phys. Rev. Lett. 100, 106804 (2008), 10.1103/PhysRevLett.100.106804, Boudarham and Kociak Phys. Rev. B 85, 245447 (2012), 10.1103/PhysRevB.85.245447]; it makes it straightforward to predict or interpret phenomena already known for localized surface plasmons such as environment-related energy shifts or the possibility of 3D mapping of the related surface charge densities [Collins et al. ACS Photonics 2, 1628 (2015), 10.1021/acsphotonics.5b00421].

Pattern of Injuries in Fatal Motorcycle Accidents Seen in Lagos State University Teaching Hospital: An Autopsy-Based Study.

PubMed

Faduyile, Francis; Emiogun, Festus; Soyemi, Sunday; Oyewole, Olugbenga; Okeke, Uche; Williams, Oluseun

2017-04-15

Deaths from motorcycle accident injuries have remained a major public health issue in Nigeria over the years. The study is to determine the age and gender distribution of the victims and to identify the cause of death and the anatomical pattern of injuries seen. This is a 5-year autopsy-based study of all motorcycle accident deaths seen in Lagos State University Teaching Hospital between December 2009 and November 2014. The data were retrieved from autopsy reports, hospital case notes extracts from police diary and were analysed using SPSS version 20. Motorcycle accidents accounted for 156 (2.8%) of all the autopsies done (5,661), and 156 (18.4%) of all Road Traffic Accidents (RTA) autopsies (849) performed over the study period, with a male: female ratio of 6:1. The peak age of victims was 31-40 years (30.9%). Head injuries accounted for most (41.4%) of the injuries seen, and the majority of the victims died of craniocerebral injury 53 (50.7%). This study showed that males in the fourth decade of life are the major victims of motorcycle accident death. The majority of the victims were the rider of the motorcycle. Most of them died of the craniocerebral injury.

Pattern of Injuries in Fatal Motorcycle Accidents Seen in Lagos State University Teaching Hospital: An Autopsy-Based Study

PubMed Central

Faduyile, Francis; Emiogun, Festus; Soyemi, Sunday; Oyewole, Olugbenga; Okeke, Uche; Williams, Oluseun

2017-01-01

BACKGROUND: Deaths from motorcycle accident injuries have remained a major public health issue in Nigeria over the years. AIM: The study is to determine the age and gender distribution of the victims and to identify the cause of death and the anatomical pattern of injuries seen. METHODOLOGY: This is a 5-year autopsy-based study of all motorcycle accident deaths seen in Lagos State University Teaching Hospital between December 2009 and November 2014. The data were retrieved from autopsy reports, hospital case notes extracts from police diary and were analysed using SPSS version 20. RESULTS: Motorcycle accidents accounted for 156 (2.8%) of all the autopsies done (5,661), and 156 (18.4%) of all Road Traffic Accidents (RTA) autopsies (849) performed over the study period, with a male: female ratio of 6:1. The peak age of victims was 31-40 years (30.9%). Head injuries accounted for most (41.4%) of the injuries seen, and the majority of the victims died of craniocerebral injury 53 (50.7%). CONCLUSION: This study showed that males in the fourth decade of life are the major victims of motorcycle accident death. The majority of the victims were the rider of the motorcycle. Most of them died of the craniocerebral injury. PMID:28507612

Evaluation of haematological, hepatic and renal functions of petroleum tanker drivers in Lagos, Nigeria.

PubMed

Awodele, Olufunsho; Sulayman, Ademola A; Akintonwa, Alade

2014-03-01

Hydrocarbons which are among the major components of petroleum products are considered toxic and have been implicated in a number of human diseases. Tanker drivers are continuously exposed to hydrocarbons by inhalation and most of these drivers do not use protective devices to prevent inhalation of petroleum products; nor do they visit hospital regularly for routine check-up. In view of this occupational hazard, we investigated the haematological, renal and hepatic functions of workers of petroleum tankers drivers in Lagos, Nigeria. Twenty-five tanker drivers' and fifteen control subjects were randomly selected based on the selection criteria of not smoking and working for minimum of 5 years as petroleum tanker driver. The liver, renal and haematological parameters were analyzed using automated clinical and haematological analyzers while the lipid peroxidation and antioxidant level tests were assayed using standard methods. There were significant (p ≤ 0.05) increases in the levels of serum alanine amino transferase (31.14±13.72; 22.38±9.89), albumin (42.50±4.69; 45.36±1.74) and alkaline phosphatase (84.04±21.89; 62.04±23.33) of petroleum tanker drivers compared with the controls. A significant (p≤0.05) increase in the levels of creatinine, urea and white blood cells of the tanker drivers, compared with the controls, were also obtained. The results have enormous health implications of continuous exposure to petroleum products reflected hepatic and renal damage of petroleum tanker drivers. Therefore, there is need for this group of workers to be sensitized on the importance of protective devises, regular medical checkup and management.

Prevalence of cardiometabolic risk factors among professional male long-distance bus drivers in Lagos, south-west Nigeria: a cross-sectional study.

PubMed

Amadi, Casmir E; Grove, Tim P; Mbakwem, Amam C; Ozoh, Obianuju B; Kushimo, Oyewole A; Wood, David A; Akinkunmi, Michael

Professional drivers are known to be at high risk of cardiovascular disease (CVD). This study was carried out to highlight these risk factors and their predictors among male long-distance professional bus drivers in Lagos, south-west Nigeria, with a view to improving health awareness in this group. Socio-demographic data, anthropometric indices, blood pressure, fasting plasma blood glucose levels and lipid and physical activity profiles of 293 drivers were measured. Mean age of the study population was 48 ± 9.7 years; 71.0 and 19.5% of the drivers used alcohol and were smokers, respectively; and 50.9% were physically inactive. The prevalence of overweight and obesity was 41.7 and 21.1%, respectively, while 39.7 and 13.9% were hypertensive and diabetic, respectively. Ninety (31.3%) subjects had impaired fasting glucose levels while 56.3% had dyslipidaemia. Predictors of hypertension were age and body mass index (BMI). BMI only was a predictor of abnormal glucose profile. Professional male long-distance bus drivers in this study showed a high prevalence of a cluster of risk factors for CVD.

Assessment of medical waste management in seven hospitals in Lagos, Nigeria.

PubMed

Awodele, Olufunsho; Adewoye, Aishat Abiodun; Oparah, Azuka Cyril

2016-03-15

Medical waste (MW) can be generated in hospitals, clinics and places where diagnosis and treatment are conducted. The management of these wastes is an issue of great concern and importance in view of potential public health risks associated with such wastes. The study assessed the medical waste management practices in selected hospitals and also determined the impact of Lagos Waste Management Authority (LAWMA) intervention programs. A descriptive cross-sectional survey method was used. Data were collected using three instrument (questionnaire, site visitation and in -depth interview). Two public (hospital A, B) and five private (hospital C, D, E, F and G) which provide services for low, middle and high income earners were used. Data analysis was done with SPSS version 20. Chi-squared test was used to determine level of significance at p < 0.05. The majority 56 (53.3%) of the respondents were females with mean age of 35.46 (±1.66) years. The hospital surveyed, except hospital D, disposes both general and medical waste separately. All the facilities have the same process of managing their waste which is segregation, collection/on-site transportation, on-site storage and off-site transportation. Staff responsible for collecting medical waste uses mainly hand gloves as personal protective equipment. The intervention programs helped to ensure compliance and safety of the processes; all the hospitals employ the services of LAWMA for final waste disposal and treatment. Only hospital B offered on-site treatment of its waste (sharps only) with an incinerator while LAWMA uses hydroclave to treat its wastes. There are no policies or guidelines in all investigated hospitals for managing waste. An awareness of proper waste management amongst health workers has been created in most hospitals through the initiative of LAWMA. However, hospital D still mixes municipal and hazardous wastes. The treatment of waste is generally done by LAWMA using hydroclave, to prevent environmental

Cooking Fuels in Lagos, Nigeria: Factors Associated with Household Choice of Kerosene or Liquefied Petroleum Gas (LPG)

PubMed Central

Okwor, Tochi J.; Adetona, Olorunfemi; Akinkugbe, Ayesha O.; Amadi, Casmir E.; Esezobor, Christopher; Adeyeye, Olufunke O.; Ojo, Oluwafemi; Nwude, Vivian N.; Mortimer, Kevin

2018-01-01

Cooking with dirty-burning fuels is associated with health risk from household air pollution. We assessed the prevalence of and factors associated with the use of cooking fuels, and attitudes and barriers towards use of liquefied petroleum gas (LPG). This was a cross-sectional, population-based survey conducted in 519 households in Lagos, Nigeria. We used a structured questionnaire to obtain information regarding choice of household cooking fuel and the attitudes towards the use of LPG. Kerosene was the most frequently used cooking fuel (n = 475, 91.5%; primary use n = 364, 70.1%) followed by charcoal (n = 159, 30.6%; primary use n = 88, 17%) and LPG (n = 86, 16.6%; primary use n = 63, 12.1%). Higher level of education, higher income and younger age were associated with LPG vs. kerosene use. Fuel expenditure on LPG was significantly lower than for kerosene (N (Naira) 2169.0 ± 1507.0 vs. N2581.6 ± 1407.5). Over 90% of non-LPG users were willing to switch to LPG but cited safety issues and high cost as potential barriers to switching. Our findings suggest that misinformation and beliefs regarding benefits, safety and cost of LPG are important barriers to LPG use. An educational intervention program could be a cost-effective approach to improve LPG adoption and should be formally addressed through a well-designed community-based intervention study. PMID:29614713

Cooking Fuels in Lagos, Nigeria: Factors Associated with Household Choice of Kerosene or Liquefied Petroleum Gas (LPG).

PubMed

Ozoh, Obianuju B; Okwor, Tochi J; Adetona, Olorunfemi; Akinkugbe, Ayesha O; Amadi, Casmir E; Esezobor, Christopher; Adeyeye, Olufunke O; Ojo, Oluwafemi; Nwude, Vivian N; Mortimer, Kevin

2018-03-31

Cooking with dirty-burning fuels is associated with health risk from household air pollution. We assessed the prevalence of and factors associated with the use of cooking fuels, and attitudes and barriers towards use of liquefied petroleum gas (LPG). This was a cross-sectional, population-based survey conducted in 519 households in Lagos, Nigeria. We used a structured questionnaire to obtain information regarding choice of household cooking fuel and the attitudes towards the use of LPG. Kerosene was the most frequently used cooking fuel ( n = 475, 91.5%; primary use n = 364, 70.1%) followed by charcoal ( n = 159, 30.6%; primary use n = 88, 17%) and LPG ( n = 86, 16.6%; primary use n = 63, 12.1%). Higher level of education, higher income and younger age were associated with LPG vs. kerosene use. Fuel expenditure on LPG was significantly lower than for kerosene ( N (Naira) 2169.0 ± 1507.0 vs. N 2581.6 ± 1407.5). Over 90% of non-LPG users were willing to switch to LPG but cited safety issues and high cost as potential barriers to switching. Our findings suggest that misinformation and beliefs regarding benefits, safety and cost of LPG are important barriers to LPG use. An educational intervention program could be a cost-effective approach to improve LPG adoption and should be formally addressed through a well-designed community-based intervention study.

Glacier Grey view from Lago Grey (Grey Lake), photographed during NASA's AirSAR 2004 campaign in Chile

NASA Image and Video Library

2004-03-11

Glacier Grey view from Lago Grey (Grey Lake), photographed during NASA's AirSAR 2004 campaign in Chile. Land visible in this photo was covered by glacier just 6 years earlier. AirSAR 2004 is a three-week expedition in Central and South America by an international team of scientists that is using an all-weather imaging tool, called the Airborne Synthetic Aperture Radar (AirSAR), located onboard NASA's DC-8 airborne laboratory. Scientists from many parts of the world are combining ground research with NASA's AirSAR technology to improve and expand on the quality of research they are able to conduct. Founded in 1959, Torres del Paine National Park encompasses 450,000 acres in the Patagonia region of Chile. This region is being studied by NASA using a DC-8 equipped with an Airborne Synthetic Aperture Radar (AirSAR) developed by scientists from NASA’s Jet Propulsion Laboratory. This is a very sensitive region that is important to scientists because the temperature has been consistently rising causing a subsequent melting of the region’s glaciers. AirSAR will provide a baseline model and unprecedented mapping of the region. This data will make it possible to determine whether the warming trend is slowing, continuing or accelerating. AirSAR will also provide reliable information on ice shelf thickness to measure the contribution of the glaciers to sea level.

Sustainable poverty amelioration through early life education in a peri-urban community of Lagos, Nigeria

PubMed Central

Campbell, Princess C.; Okechukwu, Emmanuel I.; Salako-Akande, Ajibike O.; Onyenwenyi, Anthonia O.

2010-01-01

ABSTRACT Background Daycare centres/nurseries have become popular because of the need for working mothers to leave young children with caregivers. However, the high poverty level (54% relative and 35% extreme poverty) makes it difficult for disadvantaged parents to pay the high fees charged by the centres. This study describes an attempt to economically empower mothers through the organisation of free early life education in a peri-urban community in Lagos. Objectives The aim of the study was to examine early life education for under-fives as a means of economic empowerment of mothers and sustainable poverty amelioration. Method The methodology included a non-randomised selection of 34 disadvantaged mothers by criteria, a prospective intervention utilising community resources to organise early childhood education, an in-depth interview of mothers, and observation of the outcomes over a 5-year period. Results The result of the study showed that no mother preferred keeping a child older than three years at home. Access to early childhood education gave mothers opportunity to undergo vocational training (1, 2.8%) and take up new/additional jobs (12, 35.3%). All mothers and 32 (80%) of the participating families more than doubled their income, earning up to twenty thousand Naira (approximately $182) per month from the first year of participation. Finally, selection criteria and periodic assessment of immunisation/growth monitoring records of participants’ children improved compliance with primary health care service utilisation. Conclusion Organisation of early childhood education had the potential for sustainable poverty amelioration through economic empowerment of mothers.

The prevalence and risk factors for Trichomonas vaginalis infection amongst human immunodeficiency virus-infected pregnant women attending the antenatal clinics of a university teaching hospital in Lagos, South-Western, Nigeria.

PubMed

Ijasan, Olaolopin; Okunade, Kehinde Sharafadeen; Oluwole, Ayodeji Ayotunde

2018-01-01

Trichomonas vaginalis infection is the most prevalent non-viral sexually transmitted infection worldwide. Interactions between this infection and human immunodeficiency virus (HIV) may cause adverse pregnancy outcomes such as preterm labour, premature rupture of membranes, chorioamnionitis, low birth weight and post-abortal sepsis. This study was aimed to determine the prevalence and risk factors of T. vaginalis infection amongst HIV-positive pregnant women attending antenatal care at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria. This was an analytical cross-sectional study in which 320 eligible participants which included 160 HIV-positive (case group) and 160 HIV-negative (control group) pregnant women were recruited at the antenatal clinic of LUTH. A structured pro forma was used to collect data from consenting participants after which high vaginal swabs were collected, processed and examined for T. vaginalis. The association between categorical variables was tested using the Chi-square test and Fisher's exact test where applicable. All significances were reported at P < 0.05. The prevalence of T. vaginalis infection amongst HIV-positive and HIV-negative pregnant women were 10% and 8.1%, respectively (P = 0.559). Significant risk factors for T. vaginalis infection in the HIV-positive pregnant women were early coitarche (P < 0.005) and multiple lifetime sexual partners (P = 0.021). There was no relationship between the T. vaginalis infection and the immunological markers of HIV infection. While this study does not provide grounds for universal screening of pregnant women for T. vaginalis infection as a tool of reducing HIV acquisition, especially in pregnancy, campaign to create better sexual health awareness should be commenced as a way to contributing to the reduction in T. vaginalis infection during pregnancy and perinatal transmission of HIV.

El Sistema de Formas en Colores for Teaching Grammar in Spanish

ERIC Educational Resources Information Center

Nailon, James

2010-01-01

Sistema de formas en colores (SFC) is a symbols-based system for teaching Spanish grammatical structures and concepts within a communicative context in the elementary school. The (ACTFL) Standards for Foreign Language Learning: Preparing for the 21st Century states that, "While grammar and vocabulary are essential tools for communication, it is…

Another Perspective: El Sistema--A Perspective for North American Music Educators

ERIC Educational Resources Information Center

Tunstall, Tricia

2013-01-01

Herein, Tricia Tunstall presents a critique of the article by Melissa Lesniak published in the December 2012 "Music Educators Journal," and offers a new perspective on the Venezuelan youth orchestra program known as "El Sistema." The program, which began in Caracas thirty-eight years ago, is dedicated to changing the lives of…

Knowledge and practice of prevention of mother-to-child transmission of HIV among traditional birth attendants in Lagos State, Nigeria.

PubMed

Balogun, Mobolanle; Odeyemi, Kofo

2010-04-29

Traditional birth attendants (TBAs) assist most deliveries in Nigeria. Knowing and understanding all issues surrounding HIV/AIDS and Prevention of Mother-To-Child Transmission of HIV (PMTCT) can help them to protect themselves and others. This study aimed to assess the knowledge and practice of PMTCT amongst TBAs in Lagos, Nigeria. This was a cross-sectional survey. Multistage sampling method was used to select 108 registered TBAs in 2 local governments areas who were interviewed using a pre-tested questionnaire. All the respondents were aware of HIV but their awareness of PMTCT specifically was not as high. Only 8.3% of the respondents had good level of knowledge about HIV and PMTCT and up to 13% of them claimed to be able to cure HIV using native remedies. The practices of HIV counseling of patients and referral of patients for HIV testing were low and higher levels of knowledge positively influenced these practices significantly (p < 0.05). They were also deficient in certain measures to prevent infection of patients and themselves. Most of the TBAs did not have adequate knowledge and practice of PMTCT illustrating the need for periodic PMTCT training for TBAs.

Magnetism of Al-substituted magnetite reduced from Al-hematite

NASA Astrophysics Data System (ADS)

Jiang, Zhaoxia; Liu, Qingsong; Zhao, Xiang; Roberts, Andrew P.; Heslop, David; Barrón, Vidal; Torrent, José

2016-06-01

Aluminum-substituted magnetite (Al-magnetite) reduced from Al-substituted hematite or goethite (Al-hematite or Al-goethite) is an environmentally important constituent of magnetically enhanced soils. In order to characterize the magnetic properties of Al-magnetite, two series of Al-magnetite samples were synthesized through reduction of Al-hematite by a mixed gas (80% CO2 and 20% CO) at 395°C for 72 h in a quartz tube furnace. Al-magnetite samples inherited the morphology of their parent Al-hematite samples, but only those transformed from Al-hematite synthesized at low temperature possessed surficial micropores, which originated from the release of structural water during heating. Surface micropores could thus serve as a practical fingerprint of fire or other high-temperature mineralogical alteration processes in natural environments, e.g., shear friction in seismic zones. In addition, Al substitution greatly affects the magnetic properties of Al-magnetite. For example, coercivity (Bc) increases with increasing Al content and then decreases slightly, while the saturation magnetization (Ms), Curie temperature (Tc), and Verwey transition temperature (Tv) all decrease with increasing Al content due to crystal defect formation and dilution of magnetic ions caused by Al incorporation. Moreover, different trends in the correlation between Tc and Bc can be used to discriminate titanomagnetite from Al-magnetite, which is likely to be important in environmental and paleomagnetic studies, particularly in soil.

Familial ALS

PubMed Central

Boylan, Kevin

2015-01-01

Synopsis Genes linked to ALS susceptibility are being identified at an increasing rate owing to advances in molecular genetic technology. Genetic mechanisms in ALS pathogenesis appear to exert major effects in ~10% of patients, but genetic factors at some level may be important components of disease risk in most ALS patients. Identification of gene variants associated with ALS has informed concepts of the pathogenesis of ALS, aided the identification of therapeutic targets, facilitated research to develop new ALS biomarkers, and supported the establishment of clinical diagnostic tests for ALS-linked genes. Translation of this knowledge to ALS therapy development is ongoing. PMID:26515623

Ab initio modeling of zincblende AlN layer in Al-AlN-TiN multilayers

DOE PAGES

Yadav, S. K.; Wang, J.; Liu, X. -Y.

2016-06-13

An unusual growth mechanism of metastable zincblende AlN thin film by diffusion of nitrogen atoms into Al lattice is established. Using first-principles density functional theory, we studied the possibility of thermodynamic stability of AlN as a zincblende phase due to epitaxial strains and interface effect, which fails to explain the formation of zincblende AlN. We then compared the formation energetics of rocksalt and zincblende AlN in fcc Al through direct diffusion of nitrogen atoms to Al octahedral and tetrahedral interstitials. Furthermore, the formation of a zincblende AlN thin film is determined to be a kinetically driven process, not a thermodynamicallymore » driven process.« less

Interfacial characterization of Al-Al thermocompression bonds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malik, N., E-mail: nishantmalik1987@gmail.com; SINTEF ICT, Department of Microsystems and Nanotechnology, P.O. Box 124 Blindern, N-0314 Oslo; Carvalho, P. A.

2016-05-28

Interfaces formed by Al-Al thermocompression bonding were studied by the transmission electron microscopy. Si wafer pairs having patterned bonding frames were bonded using Al films deposited on Si or SiO{sub 2} as intermediate bonding media. A bond force of 36 or 60 kN at bonding temperatures ranging from 400–550 °C was applied for a duration of 60 min. Differences in the bonded interfaces of 200 μm wide sealing frames were investigated. It was observed that the interface had voids for bonding with 36 kN at 400 °C for Al deposited both on Si and on SiO{sub 2}. However, the dicing yield was 33% for Al onmore » Si and 98% for Al on SiO{sub 2}, attesting for the higher quality of the latter bonds. Both a bond force of 60 kN applied at 400 °C and a bond force of 36 kN applied at 550 °C resulted in completely bonded frames with dicing yields of, respectively, 100% and 96%. A high density of long dislocations in the Al grains was observed for the 60 kN case, while the higher temperature resulted in grain boundary rotation away from the original Al-Al interface towards more stable configurations. Possible bonding mechanisms and reasons for the large difference in bonding quality of the Al films deposited on Si or SiO{sub 2} are discussed.« less

The enigmatic Messinian-Pliocene section of Cuevas del Almanzora (Vera Basin, SE Spain) revisited—erosional features and strontium isotope ages

NASA Astrophysics Data System (ADS)

Fortuin, A. R.; Kelling, J. M. D.; Roep, Th. B.

1995-07-01

The Cuevas del Almanzora section was, in the late seventies, the focus of a discussion because of alleged continuous marine Messinian to Pliocene sedimentation. However, a discontinuity has been shown to exist in the shape of laminated strata including the late Messinian brackish/ lacustrine "Lago Mare" biofacies. More recently, Benson and Rakic-El Bied (1991) concluded that the section is still one of the best biostratigraphic successions for the western Mediterranean in which to document terminal Miocene events, but that it entirely has an early Messinian age (i.e. it antedates deposition of the main evaporites). This paper presents strontium isotope ages indicating that the "classic" threefold division in an earlier marine Messinian, a "Lago Mare", and a Pliocene interval (sensu Geerlings et al., 1980; Cita et al., 1980) should be maintained. Moreover, the Sr isotopic composition of the euryhaline Cyprideis ostracodes from the "Lago Mare" laminites is similar to those from central Mediterranean basins. This stresses the importance of late Messinian water exchange between the Vera Basin and the then enclosed Mediterranean. It thus refutes the opinion of Benson and Rakic-El Bied (1991) that this interval is a local facies, of no particular stratigraphic importance. A time gap of up to ˜0.8 Ma between the youngest marine strata of the Messinian and the overlying Pliocene provides a maximum timing for the duration of the Messinian salinity crisis during which very little net sedimentation occurred, compared to coeval deposits in, for example, the nearby Nijar and Sorbas basins. In the Cuevas section an inconspicuous, and hitherto overlooked, erosional gap has been observed. This separates the "Lago Mare" marls from the Pliocene marls. More field observations have been made and are discussed in the light of existing interpretations, in order to demonstrate the importance of more widespread erosion in the Vera Basin. Gypsum-containing mass-flow deposits, filling up a

Thermal Modeling of Al-Al and Al-Steel Friction Stir Spot Welding

NASA Astrophysics Data System (ADS)

Jedrasiak, P.; Shercliff, H. R.; Reilly, A.; McShane, G. J.; Chen, Y. C.; Wang, L.; Robson, J.; Prangnell, P.

2016-09-01

This paper presents a finite element thermal model for similar and dissimilar alloy friction stir spot welding (FSSW). The model is calibrated and validated using instrumented lap joints in Al-Al and Al-Fe automotive sheet alloys. The model successfully predicts the thermal histories for a range of process conditions. The resulting temperature histories are used to predict the growth of intermetallic phases at the interface in Al-Fe welds. Temperature predictions were used to study the evolution of hardness of a precipitation-hardened aluminum alloy during post-weld aging after FSSW.

Proton irradiation studies on Al and Al5083 alloy

NASA Astrophysics Data System (ADS)

Bhattacharyya, P.; Gayathri, N.; Bhattacharya, M.; Gupta, A. Dutta; Sarkar, Apu; Dhar, S.; Mitra, M. K.; Mukherjee, P.

2017-10-01

The change in the microstructural parameters and microhardness values in 6.5 MeV proton irradiated pure Al and Al5083 alloy samples have been evaluated using different model based techniques of X-ray diffraction Line Profile Analysis (XRD) and microindendation techniques. The detailed line profile analysis of the XRD data showed that the domain size increases and saturates with irradiation dose both in the case of Al and Al5083 alloy. The corresponding microstrain values did not show any change with irradiation dose in the case of the pure Al but showed an increase at higher irradiation doses in the case of Al5083 alloy. The microindendation results showed that unirradiated Al5083 alloy has higher hardness value compared to that of unirradiated pure Al. The hardness increased marginally with irradiation dose in the case of Al5083, whereas for pure Al, there was no significant change with dose.

The SISTEMA Project contribution in the implementation of the GEO Geohazards Supersite initiative

NASA Astrophysics Data System (ADS)

Vilardo, Giuseppe; Sangianantoni, Agata; Borgstrom, Sven; D'Auria, Luca; De Martino, Prospero; Dolce, Mario; Isaia, Roberto; Marotta, Enrica; Martini, Marcello; Obrizzo, Francesco; Peluso, Rosario; Sansivero, Fabio; Scarpato, Giovanni; Siniscalchi, Valeria; Tammaro, Umberto; Tulino, Sabrina; Castellano, Mario; Bianco, Francesca

2017-04-01

SISTEMA Project has been funded by the PO FESR 2007-2013 action, supported by the Campania Region (Italy). The project fosters the integrated use of multidisciplinary data in order to improve the understanding of the volcanic processes at Campi Flegrei and Ischia and to progress in science and surveillance of the territory according to the rationale of Supersite GEO initiative to Campi Flegrei, currently identified as Permanent Supersite. The mission of SISTEMA is to upgrade the existing monitoring and surveillance systems through the design, purchase and installation of new instrumentation, equipment, technology and methods addressing the need of delivering, with improved rapidity, scientific information for decision makers and end-users. The redundancy of monitoring systems is an important issue to guarantee the full operability during emergencies. The Monitoring Centre of INGV-Osservatorio Vesuviano is currently located within the red zone (potentially at risk of invasion by pyroclastic flows in case of eruption) of Campi Flegrei volcano. Its position offers various logistic benefits but at the onset of a volcanic crisis, of course it will be required to shift this Center in a safer area. For this reason, within the SISTEMA project, we envisioned a backup system which, when needed, could guarantee a shift of the Center in a virtually zero time. This can be achieved by fully duplicating the processing system and the data storage. In case of emergency, it would be required only to switch on the visualization systems in the new Center and transferring the personnel involved in the surveillance activities. SISTEMA project has also enabled the development of a permanent GPS and CRs (Corner Reflectors) networks, the latter supporting SAR Interferometry, by helping to improve knowledge of the Campi Flegrei deformation field, both on local and wide scale. In addition, in order to enhance the heat flux measurements from ground based thermal camera observations, the

Combustion synthesis of AlB2-Al2O3 composite powders with AlB2 nanowire structures

NASA Astrophysics Data System (ADS)

Yang, Pan; Xiao, Guoqing; Ding, Donghai; Ren, Yun; Yang, Shoulei; Lv, Lihua; Hou, Xing

2018-05-01

Using of Al and B2O3 powders as starting materials, and Mg-Al alloy as additives, AlB2-Al2O3 composite powders with AlB2 nanowire structures were successfully fabricated via combustion synthesis method in Ar atmosphere at a pressure of 1.5 MPa. The effect of different amount of Mg-Al alloy on the phase compositions and morphology of the combustion products was investigated. The results revealed that AlB2 and Al2O3 increased, whereas Al decreased with the content of Mg-Al alloy increasing. The impurities MgAl2O4 and AlB12 would exist in the sample with adding of 18 wt% Mg-Al alloy. Interestingly, FESEM/TEM/EDS results showed that AlB2 nanowires were observed in the products when the content of Mg-Al alloy is 6 wt% and 12 wt%. The more AlB2 nanowires can be found as the content of Mg-Al alloy increased. And the yield of AlB2 nanowires with the diameter of about 200 nanometers (nm) and the length up to several tens of micrometers (μm) in the combustion product is highest when the content of Mg-Al alloy is 12 wt%. The vapor, such as Mg-Al (g), B2O2 (g), AlO (g) and Al2O (g), produced during the process of combustion synthesis, reacted with each other to yield AlB2 nanowires by vapor-solid (VS) mechanism and the corresponding model was also proposed.

Interfacial Phenomena in Al/Al, Al/Cu, and Cu/Cu Joints Soldered Using an Al-Zn Alloy with Ag or Cu Additions

NASA Astrophysics Data System (ADS)

Pstruś, Janusz; Gancarz, Tomasz

2014-05-01

The studies of soldered joints were carried out in systems: Al/solder/Al, Al/solder/Cu, Cu/solder/Cu, where the solder was (Al-Zn)EUT, (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Ag and (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Cu addition. Brazing was performed at 500 °C for 3 min. The EDS analysis indicated that the composition of the layers starting from the Cu pad was CuZn, Cu5Zn8, and CuZn4, respectively. Wetting tests were performed at 500 °C for 3, 8, 15, and 30 min, respectively. Thickness of the layers and their kinetics of growth were measured based on the SEM micrographs. The formation of interlayers was not observed from the side of Al pads. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed.

Development of lithium disilicate based glass-ceramics =

NASA Astrophysics Data System (ADS)

Fernandes, Hugo Alexandre Goncalves da Rocha

O principal objectivo deste estudo foi o desenvolvimento de vitroceramicos a base de dissilicato de litio no sistema Li2O-K2O-Al2O3-SiO2 contendo uma razao molar SiO2/Li2O muito afastada da do dissilicato de litio (Li2Si2O5) usando composicoes simples e a tecnica tradicional de fusao-vazamento de vidro de forma a obter materiais com propriedades mecanicas, termicas, quimicas e electricas superiores que permitam a utilizacao destes materiais em diversas aplicacoes funcionais. Investigou-se o fenomeno de separacao de fases, a cristalizacao e as relacoes estrutura-propriedades de vidros nos sistemas Li2O-SiO2, Li2O-Al2O3-SiO2 e Li2O-K2O-Al2O3-SiO2. Os vidros nos sistemas Li2O-SiO2 e Li2O-Al2O3-SiO2 apresentaram fraca densificacao e resultaram em materiais frageis, contrastando com a boa sinterizacao dos vidros no sistema Li2O-K2O-Al2O3-SiO2. Pequenas adicoes de Al2O3 e K2O ao sistema Li2O-SiO2 permitiram controlar a separacao de fases devido a formacao de especies de Al(IV) que confirmaram o papel de Al2O3 como formador de rede. Os compactos de po de vidro das composicoes contendo Al2O3 e K2O tratados termicamente resultaram em vitroceramicos bem densificados, apresentando dissilicato de litio como a principal fase cristalina, e valores de resistencia mecanica a flexao, resistencia quimica e condutividade electrica (173-224 MPa, 25-50 mg/cm2 e 2´10-18 S/cm, respectivamente) que possibilitam a utilizacao destes materiais em diversas aplicacoes funcionais. A adicao de P2O5, TiO2 e ZrO2 ao sistema Li2O-K2O-Al2O3-SiO2 como agentes nucleantes revelou que os vidros contendo apresentaram cristalizacao em volume, com a formacao de metassilicato de litio a temperaturas mais baixas e dissilicato de litio para as temperaturas mais elevadas, enquanto a adicao de zirconia reduz o grau de segregacao, aumenta a polimerizacao da matriz vitrea e desloca o valor de Tg para temperaturas superiores, inibindo a cristalizacao.

Client perception of service quality at the outpatient clinics of a General hospital in Lagos, Nigeria.

PubMed

Ogunnowo, Babatunde Enitan; Olufunlayo, Tolulope Florence; Sule, Salami Suberu

2015-01-01

Service quality assessments have assumed increasing importance in the last two decades. They are useful in identifying gaps in services been provided with the ultimate aim of guaranteeing quality assurance. The objective of this study was to assess the client perception of service quality at the outpatient clinics of Randle General hospital, Lagos. A descriptive cross sectional study was conducted from March to May 2013. A multistage sampling technique was used to select respondents and data was collected with the aid of modified SERVQUAL questionnaires. The data was analysed with aid of EPI-INFO 2002 and statistical significance was set at a P value 0.05 for statistical significance. Total of 400 respondents were interviewed. The mean age was 40 years with a standard deviation of 15.2 yrs. The highest mean score of 4.35 out of a possible maximum of 5 was recorded in assurance domain while the lowest mean score of 4.00 was recorded in the responsiveness domain. The overall mean score of all the domains was 4.20 with standard deviation of 0.51. Overall majority (80.8%) of respondents rated the overall service quality as good/ very good. After linear regression, the assurance domain was the most important predictor of the overall perceived service quality (p< 0.001). The overall perceived service quality was good. The major deficiencies were in the responsiveness domain and especially the waiting time. The hospital management should implement measures to improve the responsiveness of services by ensuring prompt delivery of services.

Orientation relationship of eutectoid FeAl and FeAl2.

PubMed

Scherf, A; Kauffmann, A; Kauffmann-Weiss, S; Scherer, T; Li, X; Stein, F; Heilmaier, M

2016-04-01

Fe-Al alloys in the aluminium range of 55-65 at.% exhibit a lamellar microstructure of B2-ordered FeAl and triclinic FeAl 2 , which is caused by a eutectoid decomposition of the high-temperature Fe 5 Al 8 phase, the so-called ∊ phase. The orientation relationship of FeAl and FeAl 2 has previously been studied by Bastin et al. [ J. Cryst. Growth (1978 ▸), 43 , 745] and Hirata et al. [ Philos. Mag. Lett. (2008 ▸), 88 , 491]. Since both results are based on different crystallographic data regarding FeAl 2 , the data are re-evaluated with respect to a recent re-determination of the FeAl 2 phase provided by Chumak et al. [ Acta Cryst. (2010 ▸), C 66 , i87]. It is found that both orientation relationships match subsequent to a rotation operation of 180° about a 〈112〉 crystallographic axis of FeAl or by applying the inversion symmetry of the FeAl 2 crystal structure as suggested by the Chumak data set. Experimental evidence for the validity of the previously determined orientation relationships was found in as-cast fully lamellar material (random texture) as well as directionally solidified material (∼〈110〉 FeAl || solidification direction) by means of orientation imaging microscopy and global texture measurements. In addition, a preferential interface between FeAl and FeAl 2 was identified by means of trace analyses using cross sectioning with a focused ion beam. On the basis of these habit planes the orientation relationship between the two phases can be described by ([Formula: see text]01) FeAl || (114)[Formula: see text] and [111] FeAl || [1[Formula: see text]0][Formula: see text]. There is no evidence for twinning within FeAl lamellae or alternating orientations of FeAl lamellae. Based on the determined orientation and interface data, an atomistic model of the structure relationship of Fe 5 Al 8 , FeAl and FeAl 2 in the vicinity of the eutectoid decomposition is derived. This model is analysed with respect to the strain which has to be

Juvenile delinquency among students of an approved sheltered girls' school in Lagos, Nigeria.

PubMed

Ebuehi, O M; Omogbemi, K B

2011-01-01

Juvenile delinquency is the involvement of a child younger than 18 years in behavior that violates the law. Its cost in terms of human potential, public safety and tax expenditures can be very high. Research that assesses how and why children become delinquent is a sound investment, because it can provide the foundation for effective intervention in its prevention and control. The study is to determine the factors associated with juvenile delinquency. A cross-sectional study was conducted among sixty (60) students of the approved sheltered girls' school, Idi-Araba, Lagos, using a structured interviewer-administered questionnaire. Findings revealed that the respondents were within the ages of 10-18 years with a mean age of 14.2 +/- 2.0 years, 70% had attained primary school education. Of the 53.3% that dropped out of school, 65.6% did so from financial problems, 6.3% as a result of poor performance and peer pressure accounted for 28.1%. A total of 71.7% of the students were brought to the school by the police; 52.5% on account of roaming while lack of parental control, stealing, robbery and fighting accounted for 16.9%, 11.9%, 10.2%, and 8.5% respectively. Majority (58.6%) of the students had both parents alive while 12.1% had both parents deceased. About 25 (41.7%) of the respondents admitted to committing a crime out of which 88% was stealing, 4% were involved in armed robbery and 8% in house breaking. Of all the socio-demographics characteristics of the respondents explored, only their educational level was found to be significantly associated (p = 0.0197) with criminal behaviour. Mother's educational level (p = 0.0245), maternal alcohol consumption (p = 0.0173) and kind of treatment (0.0245) received from step mums were significantly associated with criminal behaviour. Poor parental supervision, poverty and peer pressure played key roles in delinquency among the juveniles. An effective prevention and control of juvenile delinquency will require collective

Cosmogenic Surface-Exposure Dating of Boulders on Last-Glacial and Late-Glacial Moraines, Lago Buenos Aires, Argentina: Interpretive Strategies and Paleoclimate Implications

NASA Astrophysics Data System (ADS)

Douglass, D. C.; Singer, B. S.; Kaplan, M. R.; Mickelson, D. M.; Caffee, M.

2005-12-01

The most substantial and least quantifiable source of uncertainty in cosmogenic surface-exposure datasets is the variable exposure histories of boulders from the same landform. The development of precise and accurate chronologies requires distinguishing boulders that best reflect the age of the landform from those which are outliers. We use the Mean Square of Weighted Deviates statistic and cumulative frequency plots to identify groups of samples that have statistically similar ages based on the number of samples and the uncertainty associated with the analyses. This group of samples most likely represents the best estimate of the landform age. We use these tools to interpret 49 surface-exposure ages from six last-glacial and late-glacial moraines at Lago Buenos Aires, Argentina (LBA; 71.0W, 46.5S). Seven of the orty-nine samples are identified as anomalously young, and are interpreted to have been exhumed after moraine deposition. The remaining samples indicate that glacial advances or still-stands of the ice margin occurred at 22.7±0.9, 21.4±1.9, 19.8±1.1, 17.0±0.8, 15.7±0.6, and 14.4±0.9 ka (±2 σ). This maximum ice extent is roughly synchronous with maximum global ice volume and several of the re-advances are contemporaneous with Heinrich events and other Northern Hemisphere cold periods. The late-glacial readvance at ca. 14.4 ka is contemporaneous with the Antarctic Cold Reversal (ACR), and precedes the Younger Dryas Chronozone (YD). No evidence for a Younger Dryas glacial advance has been found in the Lago Buenos Aires basin. This precise glacial chronology indicates there were significant and important differences in climate across southern South America. The timing of maximum ice extent and onset of deglaciation at LBA occur ~4000 years later than in the Chilean Lake District (41S). Fossil pollen from the CLD area indicates cooler conditions between ca. 14.2 and 11.2, and increased silt in a nearby lake core provides indirect evidence for glacial

Characteristics and outcome of tetanus in adolescent and adult patients admitted to the Lagos University Teaching Hospital between 2000 and 2009.

PubMed

Bankole, Idowu A; Danesi, Mustapha A; Ojo, Oluwadamilola O; Okubadejo, Njideka U; Ojini, Frank I

2012-12-15

This study was a case record review of adult patients with tetanus admitted into Lagos University Teaching Hospital between 2000 and 2009. Of 78,009 adults admitted, 190 had tetanus, constituting 0.25% of admission. Mean age was 30.4 ± 13.8 years. Male to female ratio was 3:1. The commonest occupation was commercial motorcyclists. 96% of the patients were unimmunized and 4% that had partial immunization had localized tetanus. Commonest presentation was trismus (83%). Twenty three patients had complications, 30% had autonomic dysfunction. Mean incubation period was 11.4 ± 4.8 days, and mean duration of onset was 72 ± 45.6h. 31 patients died, case fatality rate was 16.3%. Twelve percent of those with long period of onset died while 43% with short period of onset died (P=0.002). Patients with complications (78%) died of tetanus while only 8% of those without complication died (P<0.0001). Case fatality rate is still unacceptably high for a vaccine preventable disease. Attention to primary prevention of people at risk and active surveillance to prevent complications will further reduce mortality. Copyright © 2012 Elsevier B.V. All rights reserved.

Ohmic contacts to Al-rich AlGaN heterostructures

DOE PAGES

Douglas, E. A.; Reza, S.; Sanchez, C.; ...

2017-06-06

Due to the ultra-wide bandgap of Al-rich AlGaN, up to 5.8 eV for the structures in this study, obtaining low resistance ohmic contacts is inherently difficult to achieve. A comparative study of three different fabrication schemes is presented for obtaining ohmic contacts to an Al-rich AlGaN channel. Schottky-like behavior was observed for several different planar metallization stacks (and anneal temperatures), in addition to a dry-etch recess metallization contact scheme on Al 0.85Ga 0.15N/Al 0.66Ga 0.34N. However, a dry etch recess followed by n +-GaN regrowth fabrication process is reported as a means to obtain lower contact resistivity ohmic contacts onmore » a Al 0.85Ga 0.15N/Al 0.66Ga 0.34N heterostructure. In conclusion, specific contact resistivity of 5×10 -3 Ω cm 2 was achieved after annealing Ti/Al/Ni/Au metallization.« less

Growth and stress-induced transformation of zinc blende AlN layers in Al-AlN-TiN multilayers

DOE PAGES

Li, Nan; Yadav, Satyesh K.; Wang, Jian; ...

2015-12-18

We report that AlN nanolayers in sputter deposited {111}Al/AlN/TiN multilayers exhibit the metastable zinc-blende-structure (z-AlN). Based on density function theory calculations, the growth of the z-AlN is ascribed to the kinetically and energetically favored nitridation of the deposited aluminium layer. In situ nanoindentation of the as-deposited {111}Al/AlN/TiN multilayers in a high-resolution transmission electron microscope revealed the z-AlN to wurzite AlN phase transformation through collective glide of Shockley partial dislocations on every two {111} planes of the z-AlN.

Radio refractivity gradients in the lowest 100m of the atmosphere over Lagos, Nigeria in the rainy-harmattan transition phase

NASA Astrophysics Data System (ADS)

Dairo, O. F.; Kolawole, L. B.

2018-01-01

Radio engineers and researchers in conjunction with the International Telecommunication Union (ITU) have established the pivotal role of radio refractivity to the propagation of electromagnetic energy in the troposphere. In particular, the refractivity gradient statistics for the lowest 100m in the troposphere are used to determine the probability of occurrence of anomalous propagation conditions known as ducting. The major challenge to characterising the propagation condition over any environment is accessing the data of the lowest boundary layer of the atmosphere, which is highly dynamic and turbulent in evolution. High resolution radiosonde data from the Nigerian Meteorological Agency (NiMet) were used for a synoptic study of the rain-harmattan transition phase. The rain-harmattan transition phase marks the onset of the dry season due to the movement of the intertropical convergence zone interplay between (north-easterly and south-westerly) trade winds and monsoonal circulation. The lowest 100m data were analysed to determine the frequency of ducting per month. Progressive increase in the occurrence of ducting was observed during the rain-harmattan transition phase, which coincides with the West African Monsoon retreat. The results show significant divergence from previous studies, which reported that the tropospheric condition over Lagos (Geo. 6 . 5 °N, 3 . 3 °E), Nigeria, is predominantly super-refractive.

Comparing the Thermodynamic Behaviour of Al(1)+ZrO2(s) to Al(1)+Al2O3(s)

NASA Technical Reports Server (NTRS)

Copland, Evan

2004-01-01

In an effort to better determine the thermodynamic properties of Al(g) and Al2O(g). the vapor in equilibrium with Al(l)+ZrO2(s) was compared to the vapor in equilibrium with Al(l)+Al2O3(s) over temperature range 1197-to-1509K. The comparison was made directly by Knudsen effusion-cell mass spectrometry with an instrument configured for a multiple effusion-cell vapor source (multi-cell KEMS). Second law enthalpies of vaporization of Al(g) and Al2O(g) together with activity measurements show that Al(l)+ZrO2(s) is thermodynamically equivalent to Al(l)+Al2O3(s), indicating Al(l) remained pure and Al2O3(s) was present in the ZrO2-cell. Subsequent observation of the Al(l)/ZrO2 and vapor/ZrO2 interfaces revealed a thin Al2O3-layer had formed, separating the ZrO2-cell from Al(l) and Al(g)+Al2O(g), effectively transforming it into an Al2O3 effusion-cell. This behavior agrees with recent observations made for Beta-NiAl(Pt) alloys measured in ZrO2 effusion-cell.

Nanoporous Al sandwich foils using size effect of Al layer thickness during Cu/Al/Cu laminate rolling

NASA Astrophysics Data System (ADS)

Yu, Hailiang; Lu, Cheng; Tieu, A. Kiet; Li, Huijun; Godbole, Ajit; Kong, Charlie

2018-06-01

The roll bonding technique is one of the most widely used methods to produce metal laminate sheets. Such sheets offer interesting research opportunities for both scientists and engineers. In this paper, we report on an experimental investigation of the 'thickness effect' during laminate rolling for the first time. Using a four-high multifunction rolling mill, Cu/Al/Cu laminate sheets were fabricated with a range of thicknesses (16, 40, 70 and 130 μm) of the Al layer. The thickness of the Cu sheets was a constant 300 μm. After rolling, TEM images show good bonding quality between the Cu and Al layers. However, there are many nanoscale pores in the Al layer. The fraction of nanoscale pores in the Al layer increases with a reduction in the Al layer thickness. The finite element method was used to simulate the Cu/Al/Cu rolling process. The simulation results reveal the effect of the Al layer thickness on the deformation characteristics of the Cu/Al/Cu laminate. Finally, we propose that the size effect of the Al layer thickness during Cu/Al/Cu laminate rolling may offer a method to fabricate 'nanoporous' Al sandwich laminate foils. Such foils can be used in electromagnetic shielding of electrical devices and noisy shielding of building.

El Sistema as a Bourgeois Social Project: Class, Gender, and Victorian Values

ERIC Educational Resources Information Center

Bull, Anna

2016-01-01

This article asks why classical music in the UK, which is consumed and practiced by the middle and upper classes, is being used as a social action program for working-class children in British music education schemes inspired by El Sistema. Through exploring the discourse of the social benefits of classical music in the late nineteenth century, a…

Wasting and stunting are still prevalent in children with sickle cell anaemia in Lagos, Nigeria.

PubMed

Esezobor, Christopher I; Akintan, Patricia; Akinsulie, Adebola; Temiye, Edamisan; Adeyemo, Titilope

2016-05-04

Sickle cell anaemia (SCA) is associated with growth failure. However, recent reports indicate high rates of overweight or obesity among children with SCA in developed countries. It is unclear whether overweight or obesity is also common in children with SCA in developing countries. The objectives of the study were to determine the prevalence of overweight or obesity, wasting and stunting and identify predictors of wasting and stunting among children with SCA in Nigeria. Children with SCA attending a public-funded tertiary hospital clinic were studied. Weight, height, haemoglobin, haemoglobin fractions and white cell count were measured. Anthropometric values were converted to z scores and referenced to the WHO Child Growth Standards and WHO Reference 2007. The proportions with wasting, stunting and overweight or obesity were determined. Regression analysis was used to identify the predictors of wasting and stunting. Two hundred and thirty-three children [mean (±SD) age of 9.0 (±4.0) years, 60.9 % males] participated in the study. Wasting, stunting and overweight or obesity rates were 22.7 %, 11.6 % and 1.7 %, respectively. Boys and children from low socioeconomic class were 3.25 (1.45-7.29) and 2.42 (1.14-5.18) times more likely to be wasted respectively, while both wasting and stunting were more common with increasing age [adjusted OR of 1.33 (1.18-1.51) and 1.15 (1.01-1.32) respectively]. Sickle cell-related complications and intake of oral penicillin and hydroxyurea were not associated with wasting and stunting. Overweight or obesity is uncommon while wasting and stunting are still prevalent in children with SCA in Lagos. The strongest predictors of wasting and stunting were older age, male gender and low socioeconomic status.

Determinants of climate change adaptation strategies used by fish farmers in Epe Local Government Area of Lagos State, Nigeria.

PubMed

Arimi, Kayode S

2014-05-01

Undesirable impacts of climate change have been a common occurrence that has made fish farmers in developing countries adopt some climate-change adaptation strategies. However, little is known about determinants of climate-change adaptation strategies used by these fish farmers. This study, therefore, articulates novelties on adaptation to climate change, as well ascertains determinants of adaptation strategies used by fish farmers in Epe, Lagos State, Nigeria. Climate change adaptation strategies mostly used by fish farmers include frequent seeking for early warning information about climate change (76.7%) and avoidance of areas susceptible to flooding (60.0%). Climate-change adaptation strategies used by fish farmers were significantly influenced by access to early warning information (β = 7.21), knowledge of farmers about climate change adaptation strategies (β = 8.86), access to capital (β = 28.25), and participation in workshop and conferences (β = 37.19) but were reduced by number of fish stocking (β = -2.06). The adaptation strategies used by fish farmers were autonomous and mostly determined by the access to credit facilities and information. Development policy should focus on carbon capture and storage technology in order to reduce adverse impacts of climate change, as well as making early warning information on climate change available to fish farmers. These will enhance adaptation to climate change. © 2013 Society of Chemical Industry.

Ti{sub 2}AlN thin films synthesized by annealing of (Ti+Al)/AlN multilayers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cabioch, Thierry, E-mail: Thierry.cabioch@univ-poitiers.fr; Alkazaz, Malaz; Beaufort, Marie-France

2016-08-15

Highlights: • Epitaxial thin films of the MAX phase Ti{sub 2}AlN are obtained by thermal annealing. • A new metastable (Ti,Al,N) solid solution with the structure of α-T is evidenced. • The formation of the MAX phase occurs at low temperature (600 °C). - Abstract: Single-phase Ti{sub 2}AlN thin films were obtained by annealing in vacuum of (Ti + Al)/AlN multilayers deposited at room temperature by magnetron sputtering onto single-crystalline (0001) 4H-SiC and (0001) Al{sub 2}O{sub 3} substrates. In-situ X-ray diffraction experiments combined with ex-situ cross-sectional transmission electron microscopy observations reveal that interdiffusion processes occur in the multilayer at amore » temperature of ∼400 °C leading to the formation of a (Ti, Al, N) solid solution, having the hexagonal structure of α-Ti, whereas the formation of Ti{sub 2}AlN occurs at 550–600 °C. Highly oriented (0002) Ti{sub 2}AlN thin films can be obtained after an annealing at 750 °C.« less

High prevalence of complementary and alternative medicine use among patients with sickle cell disease in a tertiary hospital in Lagos, South West, Nigeria.

PubMed

Busari, A A; Mufutau, M A

2017-06-07

Attention and interest in the use of complementary and alternative medicine (CAM) has been reignited globally, most especially in patients with chronic diseases. Sickle cell disease (SCD) is one of such chronic diseases associated with devastating clinical and psychosocial consequences, thus leading those affected to seek alternative treatment apart from orthodox medicine. Hence, this study aimed to determine the prevalence, pattern and tolerability of the use of CAM in patients with SCD in the Lagos University Teaching Hospital (LUTH). This was a cross-sectional survey of 200 respondents with SCD attending the hematology clinics of the Lagos University Teaching Hospital over a period of 3 months. Data on socio-demographic characteristic, clinical profile, the types and sources of CAM used were collected using a well structured pretested questionnaire. The data obtained were analyzed using Statistical Package for Social Sciences (SPSS®) version 17. Of the 200 patients who participated in the study, 113; 56.5% were males and 87; 43.5% were females. Majority of the SCD patients were 1-10 years old and their mean age was 18.8 ± 14.39 years. CAM was reportedly used by 88.5% of the respondents. Biological (herbal) products 156; 62.9% were the most commonly used CAM, followed by alternative medical systems 52; 20.9% and mind-body interventions 30; 12.1%. Relations, friends and neighbors influenced 85.2% of CAM users by recommending CAM to them. Tolerability of CAM was perceived to be excellent as only 33 (18.6%) of the respondents abandoned the use of CAM. Comparing CAM users and CAM non-users, there was no statistical significant difference in the proportion of those >18 years (45.76% vs 52.17%; p = 0.658), those who experienced two or more crises (51.41% vs 34.78%; p = 0.183), and those with stable haemoglobin concentration of >7 g/dL (15.81% vs 8.69%; p = 0.539) More patients among CAM non-users (91.30%) significantly spend over 3000 Naira (USD 15) per

Polybrominated diphenyl ethers and polychlorinated biphenyls in dust from cars, homes, and offices in Lagos, Nigeria.

PubMed

Harrad, Stuart; Abdallah, Mohamed Abou-Elwafa; Oluseyi, Temilola

2016-03-01

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in dust from 16 cars, 12 homes, and 18 offices in Lagos, Nigeria. These represent the first and second reports respectively of contamination of Nigerian indoor dust with these contaminants, and the second report on PCBs in car dust worldwide. Concentrations of BDE-47 and BDE-99 in two car dust samples (9300 and 3700 ng g(-1) for BDE-47 and 4200 and 19,000 ng g(-1) for BDE-99), are amongst the highest ever reported in car dust. ANOVA comparison with Canada, New Zealand, the UK, and the USA; reveals concentrations of BDEs-28, 49, 47, 66, 100, 99, 154, and 153 in Nigerian house dust, to be significantly lower than in Canada and the USA, with those of BDE-49 and 154 significantly lower than in New Zealand and the UK. Concentrations of BDE-209 in Nigeria were significantly lower than concentrations in the UK and the USA; while concentrations of PCB-180 were significantly greater than those in New Zealand, the UK, and the USA. Median concentrations of PCBs in cars were substantially higher than in the only previous study (in Kuwait and Pakistan). While median concentrations of PBDEs in cars generally exceeded those in homes, this was significant only for BDEs-49, 154, and 197, with concentrations in cars significantly greater than those in offices for BDEs-49 and 154. Contrastingly, concentrations of all target PCBs in offices exceeded significantly those in cars. This study underlines the truly global distribution of indoor contamination with PBDEs and PCBs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sexual behavior and the influencing factors among out of school female adolescents in Mushin market, Lagos, Nigeria.

PubMed

Odeyemi, Kofoworola; Onajole, Adebayo; Ogunowo, Babatunde

2009-01-01

High rates of adolescent pregnancy, sexually transmitted infections, and unsafe abortions in Nigeria indicate the need for a greater understanding of factors that affect adolescent sexuality. The sexual health needs of adolescents remain poorly known and addressed particularly among vulnerable subpopulations like out-of-school adolescents. The objective of this study was to examine the sexual behavior of female out-of-school adolescents and to identify factors that influence their sexual behavior. This cross-sectional study was conducted among a representative sample of unmarried, out-of-school female adolescents (n = 332, mean age 17 y), selected using cluster sampling, who were working in a major market (Mushin) in Lagos, Nigeria. Data were collected using interviewer administered questionnaires. Many girls (43.7%) have had sexual intercourse. The mean age at initiation was 16 years. The main reason for initiation was curiosity. Risky sexual behavior and transactional sex was common. Nonconsensual sex was also reported. Sexual health knowledge was poor, and friends served as their main source of information on sexual health issues. Factors associated with the initiation of sexual activity were friends sexual behavior, the person adolescents reside with, parents marital status, availability of funds to meet basic needs, and watching pornography (p < .05). Out-of-school female adolescents engaging in risky sexual behavior are exposed to sexual abuse, lack skills to resist pressure, and have limited access to credible reproductive health information. Appropriate interventions including provision of sexuality education and a supportive environment must be instituted to address their needs.

The role of HIV counselling and testing in sexual health behaviour change among undergraduates in Lagos, Nigeria.

PubMed

Wusu, Onipede; Okoukoni, Saturday

2011-01-01

In developing countries risky sexual behaviour among young people is on the increase. This study examined the likelihood of HIV counselling and testing (HCT) in reducing risky sexual behaviour among undergraduates in Lagos Metropolis in Nigeria. The main hypothesis tested in the study was the uptake of HCT is likely to reduce risky sexual behaviour among young undergraduates. A multistage sampling procedure was adopted to select a sample of 625 undergraduates in the study setting. A structured questionnaire was administered to respondents to elicit information on previous participation in HCT and sexual behaviour before and after participation. Result indicates that 26.1% of males and 28.9% of females ever participated in HCT. The average number of heterosexual partners kept by the respondents declined among males and females from 3.17 and 2.36, respectively before they participated in HCT to 2.27 and 1.6 after they participated in HCT. The differences in the average number of sexual partners by the respondents before and after they participated in HCT were statistically significant (P=0.000). The proportion of male respondents who engaged in frequent sex also declined from 35.8% (before participating in HCT) to 24.1% (after participating in HCT) and from 25% (before participating in HCT) to 24.7% (after participating in HCT) among females. In conclusion, participation in HCT is likely to reduce the prevalence of risky sexual behaviour among undergraduates in the study setting. Therefore, HCT is an intervention that should be emphasized.

High-resolution paleoclimate records of Holocene hydroclimatic variability in the Eastern Colombian Andes from Lago de Tota

NASA Astrophysics Data System (ADS)

Ahmed, M. N.; Bird, B. W.; Escobar, J.; Polissar, P. J.

2017-12-01

The Northern Hemisphere (NH) South American Monsoon (SAM) is a significant source of precipitation for the North Andes (north of 0˚) and has major control over regional hydroclimate variability. Holocene-length histories of NH SAM variability are few compared to the Southern Hemisphere (SH), limiting understanding of how these systems are connected on orbital and shorter timescales. Here, we present multi-proxy lake-sediment-based paleoclimate and paleohydrologic reconstructions from Lago de Tota, Colombia, using sedimentological, geochemical and leaf-wax hydrogen isotopic indicators from radiometically dated cores. The results indicate periods of wet and dry climate phases during the past 9000 BP with an average Holocene sedimentation rate 33cm/kyr. An increase in total organic matter (TOM) content and finer grain-size distributions was observed from 8000 to 3200 BP, suggesting a period of high lake level. This was followed by lower TOM and coarser grain sizes, suggesting lower lake levels from 3200 BP to the present. Although Tota's lake level pattern is antiphased with other lake level reconstructions from the NH and SH Andes, it is consistent with hypothesized changes in atmospheric convection over the Andes during the Holocene and the way in which they would be modified by the so-called dry island effect in the Colombian Andes. This suggests that a common forcing mechanism can be invoked to explain differing millennial-scale Andean hydroclimate changes, namely atmospheric convection. Orbital and Pacific atmosphere-forcing are therefore likely to have played a significant role in driving pan-Andean hydroclimate variability based on their inter-hemispheric influence on Andean convection.

The National Health Insurance Scheme (NHIS): a survey of knowledge and opinions of Nigerian dentists' in Lagos.

PubMed

Adeniyi, A A; Onajole, A T

2010-03-01

This study was designed to assess the knowledge and perceptions of Nigerian dentists to the National Health Insurance scheme (NHIS). A cross-sectional descriptive survey was conducted amongst 250 dentists employed in private and public dental clinics in Lagos State, Nigeria. The survey instrument was a self-administered questionnaire designed to assess their knowledge and attitudes towards the scheme. Data analysis was done using the Epi-Info statistical software (version 6.04). Statistical tools used included measures of central tendency, frequency distribution and chi-square test. A total of 216 dentists (response rate of 82.4%) participated in this study. Most 132 (61.1%) of the respondents had a fair knowledge of the NHIS, while 22 (10.2%) and 62 (28.7%) had poor and good knowledge respectively. Majority (70.4%) viewed the NHIS as a good idea that will succeed if properly implemented. Most (76.6%) respondents also believed that the scheme will improve access to oral health services, affordability of services (71.4%), availability of the services (68.3%) and recognition of dentistry as a profession (62.4%). Most of the respondents (66.2%) considered oral health care as not properly positioned in the NHIS and 154 respondents (74.4%) found the current position of oral health on the NHIS unacceptable. A good number of the respondents (77.3%) would like dentistry to operate at the primary care level on the NHIS. Majority of the dentists involved in this study had some knowledge of the NHIS and were generally positively disposed towards the scheme and viewed it as a good idea.

ALS Association

MedlinePlus

... toward a world without ALS! Walk to Defeat ALS® Walk to Defeat ALS® draws people of all ... We need your help. I Will Advocate National ALS Registry The National ALS Registry is a congressionally ...

Birth plans and health insurance enrolment of pregnant women: a cross-sectional survey at two secondary health facilities in Lagos, Nigeria.

PubMed

Okusanya, Babasola O; Roberts, Alero A; Akinsola, Oluwatosin J; Oye-Adeniran, Boniface A

2016-01-01

We evaluated birth plans and health insurance enrolment of pregnant women at secondary health care level as a strategy for post-2015 goals. This was a cross-sectional study at two secondary health facilities in Lagos state, Nigeria. A pre-tested questionnaire was used to collect data that were analysed and results presented with frequencies. An overall estimate with 95% confidence interval was used at significant p values of less than 0.05. Five hundred and twenty-four women, with a mean age of 3 0 ± 4.1 years, participated. Most women chose hospital delivery (84%) and had plan for transportation (86.3%) during labour. Few women were well prepared for birth (9.7%) and had health insurance (10.1%). Compared with women without insurance, more health-insured women had plans for transport in labour (p = 0.1383) and identified a place of birth (p = 0.2294), but did not have as much plan for someone to accompany them in the case of an emergency (p = 0.3855) and donate blood (p = 0.5065). Few health insured women saved money for delivery (p = 0.7439). Health insured women did not have better birth plans and expanding pregnant women's access to health insurance may be an insufficient strategy to achieve post MDG 2015 goals.

Kinematics of syn- and post-exhumational shear zones at Lago di Cignana (Western Alps, Italy): constraints on the exhumation of Zermatt-Saas (ultra)high-pressure rocks and deformation along the Combin Fault and Dent Blanche Basal Thrust

NASA Astrophysics Data System (ADS)

Kirst, Frederik; Leiss, Bernd

2017-01-01

Kinematic analyses of shear zones at Lago di Cignana in the Italian Western Alps were used to constrain the structural evolution of units from the Piemont-Ligurian oceanic realm (Zermatt-Saas and Combin zones) and the Adriatic continental margin (Dent Blanche nappe) during Palaeogene syn- and post-exhumational deformation. Exhumation of Zermatt-Saas (U)HP rocks to approximately lower crustal levels at ca. 39 Ma occurred during normal-sense top-(S)E shearing under epidote-amphibolite-facies conditions. Juxtaposition with the overlying Combin zone along the Combin Fault at mid-crustal levels occurred during greenschist-facies normal-sense top-SE shearing at ca. 38 Ma. The scarcity of top-SE kinematic indicators in the hanging wall of the Combin Fault probably resulted from strain localization along the uppermost Zermatt-Saas zone and obliteration by subsequent deformation. A phase of dominant pure shear deformation around 35 Ma affected units in the direct footwall and hanging wall of the Combin Fault. It is interpreted to reflect NW-SE crustal elongation during updoming of the nappe stack as a result of underthrusting of European continental margin units and the onset of continental collision. This phase was partly accompanied and followed by ductile bulk top-NW shearing, especially at higher structural levels, which transitioned into semi-ductile to brittle normal-sense top-NW deformation due to Vanzone phase folding from ca. 32 Ma onwards. Our structural observations suggest that syn-exhumational deformation is partly preserved within units and shear zones exposed at Lago di Cignana but also that the Combin Fault and Dent Blanche Basal Thrust experienced significant post-exhumational deformation reworking and overprinting earlier structures.

Piezo-tunnel effect in Al/Al2O3/Al junctions elaborated by atomic layer deposition

NASA Astrophysics Data System (ADS)

Rafael, R.; Puyoo, E.; Malhaire, C.

2017-11-01

In this work, the electrical transport in Al/Al2O3/Al junctions under mechanical stress is investigated in the perspective to use them as strain sensors. The metal/insulator/metal junctions are elaborated with a low temperature process (≤200 °C) fully compatible with CMOS back-end-of-line. The conduction mechanism in the structure is found to be Fowler-Nordheim tunneling, and efforts are made to extract the relevant physical parameters. Gauge factors up to -32.5 were found in the fabricated devices under tensile stress. Finally, theoretical mechanical considerations give strong evidence that strain sensitivity in Al/Al2O3/Al structures originates not only from geometrical deformations but also from the variation of interface barrier height and/or effective electronic mass in the tunneling oxide layer.

Influence of AlN(0001) Surface Reconstructions on the Wettability of an Al/AlN System: A First-Principle Study.

PubMed

Cao, Junhua; Liu, Yang; Ning, Xiao-Shan

2018-05-11

A successful application of a hot dip coating process that coats aluminum (Al) on aluminum nitride (AlN) ceramics, revealed that Al had a perfect wettability to the ceramics under specific circumstances, which was different from previous reports. In order to elucidate the mechanism that controlled the supernormal wetting phenomenon during the dip coating, a first-principle calculation of an Al(111)/AlN(0001) interface, based on the density functional theory (DFT), was employed. The wettability of the Al melt on the AlN(0001) surface, as well as the effect that the surface reconstruction of AlN and the oxygen adsorption had on Al for the adhesion and the wettability of the Al/AlN system, were studied. The results revealed that a LCM (laterally contracted monolayer) reconstruction could improve the adhesion and wettability of the system. Oxygen adsorption on the free surface of Al decreased the contact angle, because the adsorption reduced of the surface tension of Al. A prefect wetting was obtained only after some of the oxygen atoms adsorbed on the free surface of Al. The supernormal wetting phenomenon came from the surface reconstruction of the AlN and the adsorption of oxygen atoms on the Al melt surface.

Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

PubMed

Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

2016-08-15

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients. Copyright © 2016 Elsevier B.V. All rights reserved.

3-Dimensional Microstructure of Al-Al3Ti Alloy Severely Deformed by ECAP

NASA Astrophysics Data System (ADS)

Sato, Hisashi; Hishikawa, Takahisa; Makino, Yuuki; Kunimine, Takahiro; Watanabe, Yoshimi

Microstructure of Al-Al3Ti alloy deformed by Equal-Channel-Angular Pressing (ECAP) is 3-dimensionally investigated. Especially, distribution of Al3Ti particles is focused in this study. The Al-Al3Ti alloy has coarse Al3Ti platelet particles in α-Al matrix. When the Al-Al3Ti alloy is deformed by ECAP under route A, fine Al3Ti platelet particles are observed. These Al3Ti platelet particles are aligned along to deformation axis, and its plane normal is perpendicular to the deformation axis. On the other hand, Al-Al3Ti alloy ECAPed under route Bc forms several groups consisted of fine Al3Ti platelet particles. Moreover, longitudinal size of the Al3Ti particle groups is close to that of initial Al3Ti particles with 4-pass ECAP specimen. These distribution behaviors of the Al3Ti particle can be explained by plastic flow of α-Al matrix. Finally, it is concluded that distribution of Al3Ti particle in Al-Al3Ti alloy by ECAP is controlled by plastic deformation of α-Al matrix.

Abu al-Layth al-Libi

DTIC Science & Technology

2015-02-01

in the region and apparently “showed brilliance in this regard through his perfect memorization , clever understanding, persistence, and patience...Taliban’s officials quietly left the capital without informing 73 Vernie Liebl, “Al-Qaida on the US Invasion of Afghanistan in Their Own Words ,” Small Wars... memorization . A talented and charismatic orator, he also used to deliver eulogies and `Id sermons. As to `Abdallah Sa`id al-Libi, his profile is similar

Defect structures in ordered intermetallics; grain boundaries and surfaces in FeAl, NiAl, CoAl and TiAl

NASA Astrophysics Data System (ADS)

Mutasa, Batsirai Manyara

Ordered intermetallics based on transition metal aluminides have been proposed as structural materials for advanced aerospace applications. The development of these materials, which have the advantages of low density and high operating temperatures, have been focused on the aluminides of titanium, nickel and iron. Though these materials exhibit attractive properties at elevated temperatures, their utilization is limited due to their propensity for low temperature fracture and susceptibility to decreased ductility due to environmental effects. A major embrittlement mechanism at ambient temperatures in these aluminides has been by the loss of cohesive strength at the interfaces (intergranular failure). This study focuses on this mechanism of failure, by undertaking a systematic study of the energies and structures of specific grain boundaries in some of these compounds. The relaxed atomistic grain boundary structures in B2 aluminides, FeAl, NiAl and CoAl and L10 gamma-TiAl were investigated using molecular statics and embedded atom potentials in order to explore general trends for a series of B2 compounds as well as TiAl. The potentials used correctly predict the proper mechanism of compositional disorder of these compounds. Using these potentials, point defects, free surface energies and various grain boundary structures of similar energies in three B2 compounds, FeAl, NiAl and CoAl were studied. These B2 alloys exhibited increasing anti-phase boundary energies respectively. The misorientations chosen for detailed study correspond to the Sigma5(310) and Sigma5(210) boundaries. These boundaries were investigated with consideration given to possible variations in the local chemical composition. The effects of both boundary stoichiometry and bulk stoichiometry on grain boundary energetics were also considered. Defect energies were calculated for boundaries contained in both stoichiometric and off-stoichiometric bulk. The surface energies for these aluminides were also

A Rechargeable Al/S Battery with an Ionic-Liquid Electrolyte.

PubMed

Gao, Tao; Li, Xiaogang; Wang, Xiwen; Hu, Junkai; Han, Fudong; Fan, Xiulin; Suo, Liumin; Pearse, Alex J; Lee, Sang Bok; Rubloff, Gary W; Gaskell, Karen J; Noked, Malachi; Wang, Chunsheng

2016-08-16

Aluminum metal is a promising anode material for next generation rechargeable batteries owing to its abundance, potentially dendrite-free deposition, and high capacity. The rechargeable aluminum/sulfur (Al/S) battery is of great interest owing to its high energy density (1340 Wh kg(-1) ) and low cost. However, Al/S chemistry suffers poor reversibility owing to the difficulty of oxidizing AlSx . Herein, we demonstrate the first reversible Al/S battery in ionic-liquid electrolyte with an activated carbon cloth/sulfur composite cathode. Electrochemical, spectroscopic, and microscopic results suggest that sulfur undergoes a solid-state conversion reaction in the electrolyte. Kinetics analysis identifies that the slow solid-state sulfur conversion reaction causes large voltage hysteresis and limits the energy efficiency of the system. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Experiências internacionais da aplicação de sistemas de apoio à decisão clínica em gastroenterologia

PubMed Central

Tenório, Josceli Maria; Hummel, Anderson Diniz; Sdepanian, Vera Lucia; Pisa, Ivan Torres; de Fátima Marin, Heimar

2015-01-01

Objetivo Descrever as experiências recentes com a aplicação de sistemas de apoio à decisão clínica em gastroenterologia, de forma a estabelecer o nível de desenvolvimento, testes e vantagens conferidas à prática médica com a introdução desses softwares. Métodos Foi realizada busca nas bases de dados PubMed, LILACS e ISI Web of Knowledge, utilizando termos relacionados à sistemas de apoio à decisão e à gastroenterogia, incluindo artigos originais publicados no período entre 2005 e 2010. Foram recuperadas 104 publicações, na busca inicial e, após a aplicação dos critérios de inclusão e exclusão, foram eleitos nove estudos para leitura do texto completo. Resultados Os sistemas de apoio à decisão clínica apresentam grande multiplicidade de problemas clínicos e investigação de doenças. Em 89% dos casos, são descritos modelos experimentais para o desenvolvimento de sistemas de apoio à decisão clínica. A descrição dos resultados obtidos por técnicas de inteligência artificial em 78% das publicações. Em dois dos estudos foram realizadas comparações com o médico e em apenas uma publicação um estudo controlado foi descrito, mostrando evidências de melhorias na prática médica. Conclusão Os estudos mostram potenciais benefícios dos sistemas de apoio à decisão clínica à prática médica, porém, estudos controlados em ambiente real devem ser realizados para comprovar esta perspectiva. PMID:26491625

Growth of Ni-Al alloys on Ni(1 1 1), from Al deposits of various thicknesses: (II) Formation of NiAl over a Ni 3Al interfacial layer

NASA Astrophysics Data System (ADS)

Le Pévédic, S.; Schmaus, D.; Cohen, C.

2007-01-01

This paper describes the second part of a study devoted to the growth of thin Ni-Al alloys after deposition of Al on Ni(1 1 1). In the previous paper [S. Le Pévédic, D. Schmaus, C. Cohen, Surf. Sci. 600 (2006) 565] we have described the results obtained for ultra-thin Al deposits, leading, after annealing at 750 K, to an epitaxial layer of Ni 3Al(1 1 1). In the present paper we show that this regime is only observed for Al deposits smaller than 8 × 10 15 Al/cm 2 and we describe the results obtained for Al deposits exceeding this critical thickness, up to 200 × 10 15 Al/cm 2. Al deposition was performed at low temperature (around 130 K) and the alloying process was followed in situ during subsequent annealing, by Auger electron spectroscopy, low energy electron diffraction and ion beam analysis-channeling measurements, in an ultra-high vacuum chamber connected to a Van de Graaff accelerator. We evidence the formation, after annealing at 750 K, of a crystallographically and chemically well-ordered NiAl(1 1 0) layer (whose thickness depends on the deposited Al amount), over a Ni 3Al "interfacial" layer (whose thickness—about 18 (1 1 1) planes—is independent of the deposited Al amount). The NiAl overlayer is composed of three variants, at 120° from each other in the surface plane, in relation with the respective symmetries of NiAl(1 1 0) and Ni 3Al(1 1 1). The NiAl layer is relaxed (the lattice parameters of cc-B2 NiAl and fcc-L1 2 Ni 3Al differ markedly), and we have determined its epitaxial relationship. In the case of the thickest alloyed layer formed the results concerning the structure of the NiAl layer have been confirmed and refined by ex situ X-ray diffraction and information on its grain size has been obtained by ex situ Atomic Force Microscopy. The kinetics of the alloying process is complex. It corresponds to an heterogeneous growth leading, above the thin Ni 3Al interfacial layer, to a mixture of Al and NiAl over the whole Al film, up to the

Multidisciplinary ALS care improves quality of life in patients with ALS.

PubMed

Van den Berg, J P; Kalmijn, S; Lindeman, E; Veldink, J H; de Visser, M; Van der Graaff, M M; Wokke, J H J; Van den Berg, L H

2005-10-25

To examine the effect of multidisciplinary ALS care on the quality-of-life (QoL) in patients with ALS and their caregivers. In a cross-sectional study, 208 patients with ALS and their caregivers were interviewed. QoL was assessed using the 36-item Short Form Health Survey (SF-36) and two visual analogue scales (VAS). Criteria for multidisciplinary ALS care were: an ALS team headed by a consultant in rehabilitation medicine and consisting of at least a physical therapist, occupational therapist, speech pathologist, dietician and a social worker; use of the Dutch ALS consensus guidelines for ALS care; and at least six incident ALS patients per year. Clinical characteristics and functional loss of the 133 patients receiving multidisciplinary ALS care and the 75 patients receiving general ALS care were similar. The percentage of patients with adequate aids and appliances was higher in those with multidisciplinary ALS care (93.1 vs 81.3%, p = 0.008), whereas the number of visits to professional caregivers was similar in both groups. Patients in the multidisciplinary ALS care group had a better mental QoL on the SF-36 Mental Summary Score than those in the general care group (p = 0.01). The difference in QoL was most pronounced in the domains of Social Functioning and Mental Health, and was independent of the presence of aids and appliances. No significant differences were found in the SF-36 Physical Summary Score, VAS, or in QoL of caregivers of patients with ALS. High standard of care improves mental quality-of-life in patients with ALS.

Use of information and communication technology among dental students and registrars at the faculty of dental sciences, University of Lagos.

PubMed

Butali, A; Adeyemo, W L; Akinshipo, A O; Fashina, A; Savage, K O

2011-01-01

The aim of this study was to investigate the use of information technology amongst dental students, dental nursing students and resident doctors in training at the faculty of dental Surgery University of Lagos. A structured questionnaire was distributed to 58 clinical dental students in 4 th and 5 th years of training in the 2010/2011 academic year, 36 dental nursing students and 63 resident doctors undergoing specialist training. All participants have access to the computers, 2.5% within the University and 31% at home and internet cafes and about 50% have the basic skills required. A significant difference was observed between the resident doctors and clinical dental students (P = 0.003), between resident doctors and dental nursing students (P = 0.0001) when the use of computer for study was compared. Over 95% of participants have access to internet and about 50% of them use the internet for their studies. A significant difference (P = 0.005) was observed between clinical dental students and dental nursing students that use the internet and word processing. The resident doctors used the computers for multimedia and MedLine search tools more than clinical dental students (P = 0.004) and dental nursing students (0.0006). The findings of the study show that dental students and resident doctors in training have the requisite knowledge to operate the computer for use in their study and personal activities.

Close-up view of Grey Glacier from Lago Grey (Grey Lake), taken during NASA's AirSAR 2004 campaign in Chile

NASA Image and Video Library

2004-03-11

Close-up view of Grey Glacier from Lago Grey (Grey Lake), taken during NASA's AirSAR 2004 campaign in Chile. AirSAR 2004 is a three-week expedition in Central and South America by an international team of scientists that is using an all-weather imaging tool, called the Airborne Synthetic Aperture Radar (AirSAR), located onboard NASA's DC-8 airborne laboratory. Scientists from many parts of the world are combining ground research with NASA's AirSAR technology to improve and expand on the quality of research they are able to conduct. Founded in 1959, Torres del Paine National Park encompasses 450,000 acres in the Patagonia region of Chile. This region is being studied by NASA using a DC-8 equipped with an Airborne Synthetic Aperture Radar (AirSAR) developed by scientists from NASA’s Jet Propulsion Laboratory. This is a very sensitive region that is important to scientists because the temperature has been consistently rising causing a subsequent melting of the region’s glaciers. AirSAR will provide a baseline model and unprecedented mapping of the region. This data will make it possible to determine whether the warming trend is slowing, continuing or accelerating. AirSAR will also provide reliable information on ice shelf thickness to measure the contribution of the glaciers to sea level.

AlGaN-based ultraviolet light-emitting diodes on sputter-deposited AlN templates with epitaxial AlN/AlGaN superlattices

NASA Astrophysics Data System (ADS)

Zhao, Lu; Zhang, Shuo; Zhang, Yun; Yan, Jianchang; Zhang, Lian; Ai, Yujie; Guo, Yanan; Ni, Ruxue; Wang, Junxi; Li, Jinmin

2018-01-01

We demonstrate AlGaN-based ultraviolet light-emitting diodes (UV-LEDs) grown by metalorganic chemical vapor deposition (MOCVD) on sputter-deposited AlN templates upon sapphire substrates. An AlN/AlGaN superlattices structure is inserted as a dislocation filter between the LED structure and the AlN template. The full width at half maximum values for (0002) and (10 1 bar 2) X-ray rocking curves of the n-type Al0.56Ga0.44N layer are 513 and 1205 arcsec, respectively, with the surface roughness of 0.52 nm. The electron concentration and mobility measured by Hall measurement are 9.3 × 1017cm-3 and 54 cm2/V·s at room temperature, respectively. The light output power of a 282-nm LED reaches 0.28 mW at 20 mA with an external quantum efficiency of 0.32%. And the values of leakage current and forward voltage of the LEDs are ∼3 nA at -10 V and 6.9 V at 20 mA, respectively, showing good electrical performance. It is expected that the cost of the UV-LED can be reduced by using sputter-deposited AlN template.

Five Encounters with "El Sistema" International: A Venezuelan Marvel Becomes a Global Movement

ERIC Educational Resources Information Center

Booth, Eric; Tunstall, Tricia

2014-01-01

Genuine worldwide movements for social change are rare in human history. Even more rare is the phenomenon of a worldwide movement for social change through art, with teaching artists at the forefront. This article presents the evolution of such a movement now, in the global blossoming of "El Sistema," a program that seeks to change the…

Social Responsibility and Community Development: Lessons from the Sistema de Aprendizaje Tutorial in Honduras

ERIC Educational Resources Information Center

Honeyman, Catherine A.

2010-01-01

This article extends understanding of the connections between education, social capital, and development through a mixed-methods case study of the Sistema de Aprendizaje Tutorial, or SAT, an innovative secondary-level education system. The quantitative dimension of the research used survey measures of social responsibility to compare 93 SAT…

Cyclic oxidation resistance of a reaction milled NiAl-AlN composite

NASA Technical Reports Server (NTRS)

Lowell, Carl E.; Barrett, Charles A.; Whittenberger, J. D.

1990-01-01

Based upon recent mechanical property tests a NiAl-AlN composite produced by cryomilling has very attractive high temperature strength. This paper focuses on the oxidation resistance of the NiAl-AlN composite at 1473 and 1573 K as compared to that of Ni-47Al-0.15Zr, one of the most oxidation resistant intermetallics. The results of cyclic oxidation tests show that the NiAl-AlN composite has excellent properties although not quite as good as those of Ni-47Al-0.15Zr. The onset of failure of the NiAl-AlN was unique in that it was not accompanied by a change in scale composition from alumina to less protective oxides. Failure in the composite appears to be related to the entrapment of AlN particles within the alumina scale.

ALS-Plus Syndrome: Non-Pyramidal Features in a Large ALS Cohort

PubMed Central

McCluskey, Leo; Vandriel, Shannon; Elman, Lauren; Van Deerlin, Vivianna M.; Powers, John; Boller, Ashley; Wood, Elisabeth McCarty; Woo, John; McMillan, Corey T.; Rascovsky, Katya; Grossman, Murray

2014-01-01

Objective Autopsy studies show widespread pathology in amyotrophic lateral sclerosis (ALS), but clinical surveys of multisystem disease in ALS are rare. We investigated ALS-Plus syndrome, an understudied group of patients with clinical features extending beyond pyramidal and neuromuscular systems with or without cognitive/behavioral deficits. Methods In a large, consecutively-ascertained cohort of 550 patients with ALS, we documented atypical clinical manifestations. Genetic screening for C9orf72 hexanucleotide expansions was performed in 343 patients, and SOD1, TARDBP, and VCP were tested in the subgroup of patients with a family history of ALS. Gray matter and white matter imaging was available in a subgroup of 30 patients. Results Seventy-five (13.6%) patients were identified with ALS-Plus syndrome. We found disorders of ocular motility, cerebellar, extrapyramidal and autonomic functioning. Relative to those without ALS-Plus, cognitive impairment (8.0% vs 2.9%, p=0.029), bulbar-onset (49.3% vs 23.2%, p<0.001), and pathogenic mutations (20.0% vs 8.4%, p=0.015) were more than twice as common in ALS-Plus. Survival was significantly shorter in ALS-Plus (29.66 months vs 42.50 months, p=0.02), regardless of bulbar-onset or mutation status. Imaging revealed significantly greater cerebellar and cerebral disease in ALS-Plus compared to those without ALS-Plus. Conclusions ALS-Plus syndrome is not uncommon, and the presence of these atypical features is consistent with neuropathological observations that ALS is a multisystem disorder. ALS-Plus syndrome is associated with increased risk for poor survival and the presence of a pathogenic mutation. PMID:25086858

National health insurance scheme: How receptive are the private healthcare practitioners in a local government area of Lagos state.

PubMed

Christina, Campbell Princess; Latifat, Taiwo Toyin; Collins, Nnaji Feziechukwu; Olatunbosun, Abolarin Thaddeus

2014-11-01

National Health Insurance Scheme (NHIS) is one of the health financing options adopted by Nigeria for improved healthcare access especially to the low income earners. One of the key operators of the scheme is the health care providers, thus their uptake of the scheme is fundamental to the survival of the scheme. The study reviewed the uptake of the NHIS by private health care providers in a Local Government Area in Lagos State. To assess the uptake of the NHIS by private healthcare practitioners. This descriptive cross-sectional study recruited 180 private healthcare providers selected by multistage sampling technique with a response rate of 88.9%. Awareness, knowledge and uptake of NHIS were 156 (97.5%), 110 (66.8%) and 97 (60.6%), respectively. Half of the respondents 82 (51.3%) were dissatisfied with the operations of the scheme. Major reasons were failure of entitlement payment by Health Maintenance Organisations 13 (81.3%) and their incurring losses in participating in the scheme 8(50%). There was a significant association between awareness, level of education, knowledge of NHIS and registration into scheme by the respondents P-value < 0.05. Awareness and knowledge of NHIS were commendable among the private health care providers. Six out of 10 had registered with the NHIS but half of the respondents 82 (51.3%) were dissatisfied with the scheme and 83 (57.2%) regretted participating in the scheme. There is need to improve payment modalities and ensure strict adherence to laid down policies.

Valence subband coupling effect on polarization of spontaneous emissions from Al-rich AlGaN/AlN quantum wells.

PubMed

Lu, Huimin; Yu, Tongjun; Yuan, Gangcheng; Jia, Chuanyu; Chen, Genxiang; Zhang, Guoyi

2012-12-03

The optical polarization properties of Al-rich AlGaN/AlN quantum wells (QWs) were investigated using the theoretical model based on the k·p method. Numerical results show that there is valence subband coupling which can influence the peak emission wavelength and emission intensity for TE and TM polarization components from Al-rich AlGaN/AlN QWs. Especially the valence subband coupling could be strong enough when CH1 is close to HH1 and LH1 subbands to modulate the critical Al content switching dominant emissions from TE to TM polarization. It is believed that the valence subband coupling may give important influence on polarization properties of spontaneous emissions and should be considered in designing high efficiency AlGaN-based ultraviolet (UV) LEDs.

Modulating optical polarization properties of Al-rich AlGaN/AlN quantum well by controlling wavefunction overlap

NASA Astrophysics Data System (ADS)

Chen, X. J.; Yu, T. J.; Lu, H. M.; Yuan, G. C.; Shen, B.; Zhang, G. Y.

2013-10-01

Using modified k.p perturbation method, the optical polarization properties of Al-rich AlGaN/AlN quantum wells (QWs) are studied. It is found that change of wavefunction overlaps between conduction band and valance subbands of heavy hole, light hole, and crystal-field split off hole is different. Such difference leads to the overturn of polarization degree and modulates optical polarization properties as well width and strain vary. This prompts that changing wavefunction overlaps of electron and hole can lead to a way to modulate optical polarization properties of Al-rich AlGaN/AlN QWs, on no condition that valence band order changes.

Effect of AlB2 on the P-threshold in Al-Si alloy

NASA Astrophysics Data System (ADS)

Wu, Yuying; Liu, Xiangfa

2018-06-01

The nucleation of primary Si in Al-Si alloys has been investigated in this work. It was found that there was a threshold concentration of P, below which AlP can not heterogeneous nucleate primary Si in Al-12 wt%Si alloy. AlB2 can not nucleate primary Si directly, but the presence of AlB2 may assist the nucleation of AlP leading to the nucleation of primary Si particles. In addition, with addition of AlB2, the nucleation efficiency of AlP can be improved in Al-18 wt%Si alloy. The orientation relationship between AlB2 and AlP has been calculated, and the adsorption model for AlB2 and AlP was proposed in this work.

Rational use of medicines: assessing progress using primary health centres in Shomolu local government area of Lagos, Nigeria.

PubMed

Oyeyemi, A S; Ogunleye, O A

2013-01-01

Medicines (drugs) are a critical component in the prevention and treatment of diseases. Their rational use is important to maximize their benefits and prevent undesirable effects. This study was conducted to assess progress with rational use of medicines at primary care level using recommended indicators. The cross-sectional descriptive study was conducted in four primary health centres in Somolu Local Government Area (LGA) of Lagos State, Nigeria. It employed retrospective and prospective data collection methods. From the four centres, prescription notes of 600 clinical encounters spanning one year were analyzed for prescribing indicators and a checklist was administered for facility indicators. For the 600 clinical encounters studied, 2802 drugs were prescribed. The mean number of drugs per encounter was 4.7 ± 2.1; 75.6% of drugs were prescribed by generic name; prescriptions containing at least an antibiotic averaged 48.5%, while those with at least an injection prescribed were 21%. Of all the drugs prescribed, 83.2% were from the National Essential Drugs List (NEDL). On the average, 86.5% of key essential drugs were available in the health centres but none of the centres had a copy of the NEDL or drug formulary. There were wide variations in some of the indicators across the four facilities. The study showed progress in some indicators when compared with previous studies but gaps still exist. We recommend training on rational use of medicines for health workers in the facilities and distribution of copies of NEDL to all the facilities.

High temperature deformation of NiAl and CoAl

NASA Technical Reports Server (NTRS)

Nix, W. D.

1982-01-01

The high temperature mechanical properties of the aluminides are reviewed with respect to their potential as high temperature structural materials. It is shown that NiAl and CoAl are substantially stronger than the pure metals Ni and Co at high temperatures and approach the strength of some superalloys, particularly when those superalloys are tested in "weak" directions. The factors that limit and control the high temperature strengths of NiAl and CoAl are examined to provide a basis for the development of intermetallic alloys of this type.

Sistemas Correctores de Campo Para EL Telescopio Ritchey-Chretien UNAM212

NASA Astrophysics Data System (ADS)

Cobos, F. J.; Galan, M. J.

1987-05-01

El telescopio UNAM2l2 fue inaugurado hace siete años y concebido para trabajar en las razones focales: f/7.5, F/13.5, F/27 y F/98. El diseño Ritchey-Chretién corresponde a la razón focal F/7.5 y el foco primario (F/2.286) no se consideró como utilizable para fotografía directa. En el Instituto de Astronomía de la UNAM, se diseñó y construyó un sistema corrector de campo para la razón focal F/7.5, que actualmente está en funcionamiento. Dentro de un programa de colaboración en diseflo y evaluación de sistemas ópticos, entre el Instituto de Astrofísica de Canarias y el Instituto de Astronomía de la UNAM, decidimos intentar el diseño de una correctora de campo para el foco primario del tȩlescopio UNAM212 bajo la consideración de que no son insalvables los problemas que implicaría su instalación y de que es muy posible que, en un futuro relativamente cercano, podamom tener un detector bidimenmional tipo Mepsicrón cuya área sensible haga tentadora la idea de construir la cámara directa para foco primario

Atomistic Modeling of RuAl and (RuNi) Al Alloys

NASA Technical Reports Server (NTRS)

Gargano, Pablo; Mosca, Hugo; Bozzolo, Guillermo; Noebe, Ronald D.; Gray, Hugh R. (Technical Monitor)

2002-01-01

Atomistic modeling of RuAl and RuAlNi alloys, using the BFS (Bozzolo-Ferrante-Smith) method for alloys is performed. The lattice parameter and energy of formation of B2 RuAl as a function of stoichiometry and the lattice parameter of (Ru(sub 50-x)Ni(sub x)Al(sub 50)) alloys as a function of Ni concentration are computed. BFS based Monte Carlo simulations indicate that compositions close to Ru25Ni25Al50 are single phase with no obvious evidence of a miscibility gap and separation of the individual B2 phases.

Knowledge and Acceptability of Human Papillomavirus Vaccination among Women Attending the Gynaecological Outpatient Clinics of a University Teaching Hospital in Lagos, Nigeria.

PubMed

Okunade, Kehinde S; Sunmonu, Oyebola; Osanyin, Gbemisola E; Oluwole, Ayodeji A

2017-01-01

This study was aimed at determining the knowledge and acceptability of HPV vaccine among women attending the gynaecology clinics of the Lagos University Teaching Hospital (LUTH). This was a descriptive cross-sectional study involving 148 consecutively selected women attending the gynaecology clinic of LUTH. Relevant information was obtained from these women using an interviewer-administered questionnaire. The data was analysed and then presented by simple descriptive statistics using tables and charts. Chi-square statistics were used to test the association between the sociodemographical variables and acceptance of HPV vaccination. All significance values were reported at P < 0.05. The mean age of the respondents was 35.7 ± 9.7 years. The study showed that 36.5% of the respondents had heard about HPV infection while only 18.9% had knowledge about the existence of HPV vaccines. Overall, 81.8% of the respondents accepted that the vaccines could be administered to their teenage girls with the level of education of the mothers being the major determinant of their acceptability ( P = 0.013). Awareness of HPV infections and existence of HPV vaccines is low. However, the acceptance of HPV vaccines is generally high. Efforts should be made to increase the awareness about cervical cancer, its aetiologies, and prevention via HPV vaccination.

Paleoenvironmental dynamics in South Amazonia, Brazil, during the last 35,000 years inferred from pollen and geochemical records of Lago do Saci

NASA Astrophysics Data System (ADS)

Fontes, D.; Cordeiro, R. C.; Martins, G. S.; Behling, H.; Turcq, B.; Sifeddine, A.; Seoane, J. C. S.; Moreira, L. S.; Rodrigues, R. A.

2017-10-01

Paleoenvironmental changes for the last 35,000 years were reconstructed from palynological, sedimentological and organic geochemical evidence from a well-dated sediment core from Lago do Saci (South Amazonia). Dry climatic conditions occurred between 35,000 and 18,200 cal yr BP as recorded by high frequencies of open savanna taxa and low lake level indicated by Sagittaria and low Total Organic Carbon content. Cold temperatures are indicated by the presence of Podocarpus and Ilex. A sedimentation hiatus observed between 18,200 and 9200 cal yr BP was likely related to dry conditions. The beginning of the Holocene was marked by rainforest expansion and an increase in carbon content that represented high lake levels and warmer and wetter climate conditions. Between 7500 and 5000 cal yr BP, the expansion of open savanna, seasonal forest elements and abundant black carbon suggests a dry phase. After 5000 cal yr BP, rainforest expansion and higher lake levels indicate a return to wetter conditions. A reduction of flooding taxa (Celtis and Mauritia) between 1800 and 1300 cal yr BP, high lake level conditions and maintenance of a forest physiognomy, suggests a decrease of regional precipitation and subsequent reduction of the flooded areas in a still humid climate regime.

Al6H18: A baby crystal of γ-AlH3

NASA Astrophysics Data System (ADS)

Kiran, B.; Kandalam, Anil K.; Xu, Jing; Ding, Y. H.; Sierka, M.; Bowen, K. H.; Schnöckel, H.

2012-10-01

Using global-minima search methods based on the density functional theory calculations of (AlH3)n (n = 1-8) clusters, we show that the growth pattern of alanes for n ≥ 4 is dominated by structures containing hexa-coordinated Al atoms. This is in contrast to the earlier studies where either linear or ring structures of AlH3 were predicted to be the preferred structures in which the Al atoms can have a maximum of five-fold coordination. Our calculations also reveal that the Al6H18 cluster, with its hexa-coordination of the Al atoms, resembles the unit-cell of γ-AlH3, thus Al6H18 is designated as the "baby crystal." The fragmentation energies of the (AlH3)n (n = 2-8) along with the dimerization energies for even n clusters indicate an enhanced stability of the Al6H18 cluster. Both covalent (hybridization) and ionic (charge) contribution to the bonding are the driving factors in stabilizing the isomers containing hexa-coordinated Al atoms.

MOSES: a Symbiosis Between the Lagos Ciência Viva Science Centre and a Research Project from the University of the Algarve

NASA Astrophysics Data System (ADS)

Leote, Catarina; Moura, Delminda; Azevedo Rodrigues, Luis

2017-04-01

Geoscience education is key for the understanding of our home, the planet Earth. The Lagos Ciência Viva Science Centre (CCVL) in Portugal develops various geoscience activities including astronomy sessions, geology, paleontology and oceanography field trips, complementary primary school classes, seminars and numerous workshops for a public ranging from pre-schoolers to seniors . Our experience in geoscience communication and informal education also includes a formal partnership with a research centre from the University of the Algarve, the CIMA - Centre for Marine and Environmental Research, through the project MOSES, which focuses on sand transport along crenulated coasts. Based on the project goals, methods and results, the CCVL team designed a communication and outreach plan including a seminar, a field trip and a workshop, to alert for the subjects of coastal erosion and management, both highly relevant in the Algarve. This partnership was highly beneficial for both parts as it facilitated the communication of a scientific project to the public, while the CCVL had the opportunity to update and expand its educational offer. This type of interaction between universities/research institutes and science centres/museums allows scientists to focus on their research work, reducing their need to invest in communication, and provides good and updated scientific contents to science communicators, ensuring a direct channel between scientific research and the public.

27Al MQMAS of the δ-Al 13-Keggin

DOE PAGES

Pilgrim, C. D.; Callahan, J. R.; Colla, C. A.; ...

2017-01-20

Here, one-dimensional 27Al, 23Na Magic-Angle-Spinning (MAS) NMR and 27Al Multiple-Quantum Magic-Angle-Spinning NMR (MQMAS) measurements are reported for the δ-isomer of the Al 13 Keggin structure at high spinning speed and 14.1 T field. Values for the CQ and η parameters are on the same scale as those seen in other isomers of the Al 13 structure. Density functional theory (DFT) calculations are performed for comparison to the experimental fits using the B3PW91/6-31+G* and PBE0/6-31+G* levels of theory, with the Polarizable Continuum Model (PCM).

Pressure induced coordination change of Al in silicate melts from Al K edge XANES of high pressure NaAlSi2O6-NaAlSi3O8 glasses

NASA Astrophysics Data System (ADS)

Li, Dien; Secco, R. A.; Bancroft, G. M.; Fleet, M. E.

Aluminum K-edge XANES spectra of high pressure and high temperature (4.4 GPa and 1575°C) glasses along the NaAlSi2O6 (Jd)-NaAlSi3O8 (Ab) join are reported using synchrotron radiation, and shown to provide direct experimental evidence for the pressure-induced coordination change of Al. Five- and six-fold coordinated Al (5Al and 6Al), characterized by Al K-edge positions at 1567.8 and 1568.7 eV, respectively, first appear in glass of composition Jd60Ab40 and increase in proportion progressively with increasing Jd content. The end-member jadeite glass contains about 6% of each of 5Al and 6Al. The present direct measurements confirm literature suggestions for the important role of Al in controlling viscosity and diffusion in mantle melts.

Assessing behavioural changes in ALS: cross-validation of ALS-specific measures.

PubMed

Pinto-Grau, Marta; Costello, Emmet; O'Connor, Sarah; Elamin, Marwa; Burke, Tom; Heverin, Mark; Pender, Niall; Hardiman, Orla

2017-07-01

The Beaumont Behavioural Inventory (BBI) is a behavioural proxy report for the assessment of behavioural changes in ALS. This tool has been validated against the FrSBe, a non-ALS-specific behavioural assessment, and further comparison of the BBI against a disease-specific tool was considered. This study cross-validates the BBI against the ALS-FTD-Q. Sixty ALS patients, 8% also meeting criteria for FTD, were recruited. All patients were evaluated using the BBI and the ALS-FTD-Q, completed by a carer. Correlational analysis was performed to assess construct validity. Precision, sensitivity, specificity, and overall accuracy of the BBI when compared to the ALS-FTD-Q, were obtained. The mean score of the whole sample on the BBI was 11.45 ± 13.06. ALS-FTD patients scored significantly higher than non-demented ALS patients (31.6 ± 14.64, 9.62 ± 11.38; p < 0.0001). A significant large positive correlation between the BBI and the ALS-FTD-Q was observed (r = 0.807, p < 0.0001), and no significant correlations between the BBI and other clinical/demographic characteristics indicate good convergent and discriminant validity, respectively. 72% of overall concordance was observed. Precision, sensitivity, and specificity for the classification of severely impaired patients were adequate. However, lower concordance in the classification of mild behavioural changes was observed, with higher sensitivity using the BBI, most likely secondary to BBI items which endorsed behavioural aspects not measured by the ALS-FTD-Q. Good construct validity has been further confirmed when the BBI is compared to an ALS-specific tool. Furthermore, the BBI is a more comprehensive behavioural assessment for ALS, as it measures the whole behavioural spectrum in this condition.

Doping and compensation in Al-rich AlGaN grown on single crystal AlN and sapphire by MOCVD

NASA Astrophysics Data System (ADS)

Bryan, Isaac; Bryan, Zachary; Washiyama, Shun; Reddy, Pramod; Gaddy, Benjamin; Sarkar, Biplab; Breckenridge, M. Hayden; Guo, Qiang; Bobea, Milena; Tweedie, James; Mita, Seiji; Irving, Douglas; Collazo, Ramon; Sitar, Zlatko

2018-02-01

In order to understand the influence of dislocations on doping and compensation in Al-rich AlGaN, thin films were grown by metal organic chemical vapor deposition (MOCVD) on different templates on sapphire and low dislocation density single crystalline AlN. AlGaN grown on AlN exhibited the highest conductivity, carrier concentration, and mobility for any doping concentration due to low threading dislocation related compensation and reduced self-compensation. The onset of self-compensation, i.e., the "knee behavior" in conductivity, was found to depend only on the chemical potential of silicon, strongly indicating the cation vacancy complex with Si as the source of self-compensation. However, the magnitude of self-compensation was found to increase with an increase in dislocation density, and consequently, AlGaN grown on AlN substrates demonstrated higher conductivity over the entire doping range.

The Existence of a Designer Al=Al Double Bond in the LiAl2 H4- Cluster Formed by Electronic Transmutation.

PubMed

Lundell, Katie A; Zhang, Xinxing; Boldyrev, Alexander I; Bowen, Kit H

2017-12-22

The Al=Al double bond is elusive in chemistry. Herein we report the results obtained via combined photoelectron spectroscopy and ab initio studies of the LiAl 2 H 4 - cluster that confirm the formation of a conventional Al=Al double bond. Comprehensive searches for the most stable structures of the LiAl 2 H 4 - cluster have shown that the global minimum isomer I possesses a geometric structure which resembles that of Si 2 H 4 , demonstrating a successful example of the transmutation of Al atoms into Si atoms by electron donation. Theoretical simulations of the photoelectron spectrum discovered the coexistence of two isomers in the ion beam, including the one with the Al=Al double bond. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lou Gehrig's Disease (ALS)

MedlinePlus

... for Educators Search English Español Lou Gehrig's Disease (ALS) KidsHealth / For Kids / Lou Gehrig's Disease (ALS) What's ... with ALS in the 1930s. What Happens in ALS? ALS damages motor neurons in the brain and ...

Characterization of N-polar AlN in GaN/AlN/(Al,Ga)N heterostructures grown by metal-organic chemical vapor deposition

NASA Astrophysics Data System (ADS)

Li, Haoran; Mazumder, Baishakhi; Bonef, Bastien; Keller, Stacia; Wienecke, Steven; Speck, James S.; Denbaars, Steven P.; Mishra, Umesh K.

2017-11-01

In GaN/(Al,Ga)N high-electron-mobility transistors (HEMT), AlN interlayer between GaN channel and AlGaN barrier suppresses alloy scattering and significantly improves the electron mobility of the two-dimensional electron gas. While high concentrations of gallium were previously observed in Al-polar AlN interlayers grown by metal-organic chemical vapor deposition, the N-polar AlN (Al x Ga1-x N) films examined by atom probe tomography in this study exhibited aluminum compositions (x) equal to or higher than 95% over a wide range of growth conditions. The also investigated AlN interlayer in a N-polar GaN/AlN/AlGaN/ S.I. GaN HEMT structure possessed a similarly high x content.

Pure AlN layers in metal-polar AlGaN/AlN/GaN and AlN/GaN heterostructures grown by low-temperature ammonia-based molecular beam epitaxy

NASA Astrophysics Data System (ADS)

Kaun, Stephen W.; Mazumder, Baishakhi; Fireman, Micha N.; Kyle, Erin C. H.; Mishra, Umesh K.; Speck, James S.

2015-05-01

When grown at a high temperature (820 °C) by ammonia-based molecular beam epitaxy (NH3-MBE), the AlN layers of metal-polar AlGaN/AlN/GaN heterostructures had a high GaN mole fraction (∼0.15), as identified by atom probe tomography in a previous study (Mazumder et al 2013 Appl. Phys. Lett. 102 111603). In the study presented here, growth at low temperature (<740 °C) by NH3-MBE yielded metal-polar AlN layers that were essentially pure at the alloy level. The improved purity of the AlN layers grown at low temperature was correlated to a dramatic increase in the sheet density of the two-dimensional electron gas (2DEG) at the AlN/GaN heterointerface. Through application of an In surfactant, metal-polar AlN(3.5 nm)/GaN and AlGaN/AlN(2.5 nm)/GaN heterostructures grown at low temperature yielded low 2DEG sheet resistances of 177 and 285 Ω/□, respectively.

Interdiffusion in U 3Si-Al, U 3Si 2-Al, and USi-Al dispersion fuels during irradiation

NASA Astrophysics Data System (ADS)

Kim, Yeon Soo; Hofman, Gerard L.

2011-03-01

Uranium-silicide compound fuel dispersion in an Al matrix is used in research and test reactors worldwide. Interaction layer (IL) growth between fuel particles and the matrix is one of performance issues. The interaction layer growth data for U 3Si, U 3Si 2 and USi dispersions in Al were obtained from both out-of-pile and in-pile tests. The IL is dominantly U(AlSi) 3 from out-of-pile tests, but its (Al + Si)/U ratio from in-pile tests is higher than the out-of-pile data, because of amorphous behavior of the ILs. IL growth correlations were developed for U 3Si-Al and U 3Si 2-Al. The IL growth rates were dependent on the U/Si ratio of the fuel compounds. During irradiation, however, the IL growth rates did not decrease with the decreasing U/Si ratio by fission. It is reasoned that transition metal fission products in the IL compensate the loss of U atoms by providing chemical potential for Al diffusion and volume expansion by solid swelling and gas bubble swelling. The addition of Mo in U 3Si 2 reduces the IL growth rate, which is similar to that of UMo alloy dispersion in a silicon-added Al matrix.

ALS - resources

MedlinePlus

Resources - ALS ... The following organizations are good resources for information on amyotrophic lateral sclerosis : Muscular Dystrophy Association -- www.mda.org/disease/amyotrophic-lateral-sclerosis National Amyotrophic Lateral Sclerosis (ALS) ...

Study of the Al m 26 ( d , p ) Al 27 Reaction and the Influence of the Al 26 0 + Isomer on the Destruction of Al 26 in the Galaxy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Almaraz-Calderon, S.; Rehm, K. E.; Gerken, N.

The existence of 26Al (t 1/2 = 7.17 × 10 5 yr) in the interstellar medium provides a direct confirmation of ongoing nucleosynthesis in the Galaxy. The presence of a low-lying 0 + isomer ( 26Al m), however, severely complicates the astrophysical calculations. Here we present for the first time a study of the 26Al m (d, p) 27 Al reaction using an isomeric 26Al beam. The selectivity of this reaction allowed the study of ℓ = 0 transfers to T = 1/2, and T = 3/2 states in 27Al . Mirror symmetry arguments were then used to constrain themore » 26Al m (p,γ) 27Si reaction rate and provide an experimentally determined upper limit of the rate for the destruction of isomeric 26Al via radiative proton capture reactions, which is expected to dominate the destruction path of 26Al m in asymptotic giant branch stars, classical novae, and core collapse supernovae.« less

Study of the Al m 26 ( d , p ) Al 27 Reaction and the Influence of the Al 26 0 + Isomer on the Destruction of Al 26 in the Galaxy

DOE PAGES

Almaraz-Calderon, S.; Rehm, K. E.; Gerken, N.; ...

2017-08-17

The existence of 26Al (t 1/2 = 7.17 × 10 5 yr) in the interstellar medium provides a direct confirmation of ongoing nucleosynthesis in the Galaxy. The presence of a low-lying 0 + isomer ( 26Al m), however, severely complicates the astrophysical calculations. Here we present for the first time a study of the 26Al m (d, p) 27 Al reaction using an isomeric 26Al beam. The selectivity of this reaction allowed the study of ℓ = 0 transfers to T = 1/2, and T = 3/2 states in 27Al . Mirror symmetry arguments were then used to constrain themore » 26Al m (p,γ) 27Si reaction rate and provide an experimentally determined upper limit of the rate for the destruction of isomeric 26Al via radiative proton capture reactions, which is expected to dominate the destruction path of 26Al m in asymptotic giant branch stars, classical novae, and core collapse supernovae.« less

Study of the ^{26}Al^{m}(d,p)^{27}Al Reaction and the Influence of the ^{26}Al 0^{+} Isomer on the Destruction of ^{26}Al in the Galaxy.

PubMed

Almaraz-Calderon, S; Rehm, K E; Gerken, N; Avila, M L; Kay, B P; Talwar, R; Ayangeakaa, A D; Bottoni, S; Chen, A A; Deibel, C M; Dickerson, C; Hanselman, K; Hoffman, C R; Jiang, C L; Kuvin, S A; Nusair, O; Pardo, R C; Santiago-Gonzalez, D; Sethi, J; Ugalde, C

2017-08-18

The existence of ^{26}Al (t_{1/2}=7.17×10^{5}  yr) in the interstellar medium provides a direct confirmation of ongoing nucleosynthesis in the Galaxy. The presence of a low-lying 0^{+} isomer (^{26}Al^{m}), however, severely complicates the astrophysical calculations. We present for the first time a study of the ^{26}Al^{m}(d,p)^{27}Al reaction using an isomeric ^{26}Al beam. The selectivity of this reaction allowed the study of ℓ=0 transfers to T=1/2, and T=3/2 states in ^{27}Al. Mirror symmetry arguments were then used to constrain the ^{26}Al^{m}(p,γ)^{27}Si reaction rate and provide an experimentally determined upper limit of the rate for the destruction of isomeric ^{26}Al via radiative proton capture reactions, which is expected to dominate the destruction path of ^{26}Al^{m} in asymptotic giant branch stars, classical novae, and core collapse supernovae.

Reduced electron back-injection in Al2O3/AlOx/Al2O3/graphene charge-trap memory devices

NASA Astrophysics Data System (ADS)

Lee, Sejoon; Song, Emil B.; Min Kim, Sung; Lee, Youngmin; Seo, David H.; Seo, Sunae; Wang, Kang L.

2012-12-01

A graphene charge-trap memory is devised using a single-layer graphene channel with an Al2O3/AlOx/Al2O3 oxide stack, where the ion-bombarded AlOx layer is intentionally added to create an abundance of charge-trap sites. The low dielectric constant of AlOx compared to Al2O3 reduces the potential drop in the control oxide Al2O3 and suppresses the electron back-injection from the gate to the charge-storage layer, allowing the memory window of the device to be further extended. This shows that the usage of a lower dielectric constant in the charge-storage layer compared to that of the control oxide layer improves the memory performance for graphene charge-trap memories.

A comparison of basic and state-of-the-arts skills sets of biomedical science technical staff in Lagos public universities.

PubMed

John, T A

2011-12-01

Biomedical science has advanced drastically in developed countries in the last two decades with many health and economic benefits. In Nigeria, biomedical science has not thrived and the contribution from Nigerian universities, indeed African universities, to publications in global high impact journals is low. The present work was based on the hypothesis that there is a lack of state-of-the-arts experimentation in Nigerian biomedical science experiments. An investigation was carried out on the professional skills of biomedical science technical staff of the two (federal and state) public universities in Lagos, Nigeria using a closed-ended questionnaire survey. The 17 respondents were asked about their training, the frequency of utilization of 99 skills, and their expertise. The respondents were "untrained" more in state-of-the-arts skills (34% for electrophoresis, 28% for genomics, 22% for immunochemistry, and 34% for proteomics skills) than in general professional skills (5%), basic technical equipment skills (16%), or general biomedical science knowledge and skills (16%). Frequencies of responses were higher for general skills than for state-of-the-arts skills in the responses "utilizing frequently" (9.96%-31-61% versus 0.36%-4.2%), and "I'm expert" (9.55%-19.88% versus 5.88%-8.48%). It was projected that with continued investment in modern equipment and infrastructure, there will be increased drive for training and usage of modern bioscience research skills and multidisciplinary approaches and production of high-tech scientific publications.

77 FR 73732 - In the Matter of Amendment of the Designation of al-Qa'ida in Iraq, aka Jam'at al Tawhid wa'al...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-11

...'ida in Iraq, aka Jam'at al Tawhid wa'al-Jihad, aka The Monotheism and Jihad Group, aka The al-Zarqawi Network, aka al-Tawhid, aka Tanzim Qa`idat al-Jihad fi Bilad al-Rafidayn, aka The Organization of al-Jihad... Rivers, aka al-Qaida of Jihad Organization in the Land of the Two Rivers, aka al- Qaida Group of Jihad in...

Phenotypic and genotypic studies of ALS cases in ALS-SMA families.

PubMed

Corcia, Philippe; Vourc'h, Patrick; Blasco, Helene; Couratier, Philippe; Dangoumau, Audrey; Bellance, Remi; Desnuelle, Claude; Viader, Fausto; Pautot, Vivien; Millecamps, Stephanie; Bakkouche, Salah; Salachas, FranÇois; Andres, Christian R; Meininger, Vincent; Camu, William

2018-08-01

Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are the most frequent motor neuron disorders in adulthood and infancy, respectively. There is a growing literature supporting common pathophysiological patterns between those disorders. One important clinical issue for that is the co-occurrence of both diseases within a family. To collect families in which ALS and SMA patients co-exist and describe the phenotype and the genotype of ALS patients. Nine families with co-occurrence of SMA and ALS have been gathered over the last 15 years. Epidemiological, phenotype and genetic status were collected. Out of the nine families, six corresponded to the criteria of familial ALS (FALS). Clinical data were available for 11 patients out of the 15 ALS cases. Mean age of onset was 58.5 years, site of onset was lower limbs in nine cases (81.8%), median duration was 22 months. Four ALS patients carried a mutation: three mutations in SOD1 gene (G147N in two cases and one with E121G) and one repeat expansion in the C9ORF72 gene. Three patients had abnormal SMN1 copy numbers. While the high proportion of familial history of ALS cases in these ALS-SMA pedigrees could have suggested that these familial clusters of the two most frequent MND rely on a genetic background, we failed to exclude that this occurred by chance.

Distribution and size of lava shields on the Al Haruj al Aswad and the Al Haruj al Abyad Volcanic Systems, Central Libya

NASA Astrophysics Data System (ADS)

Elshaafi, Abdelsalam; Gudmundsson, Agust

2017-05-01

The Al Haruj Volcanic Province (AHVP) consists of two distinct volcanic systems. In the north is the system of Al Haruj al Aswad, covering an area of 34,200 km2, while in the south the system of Al Haruj al Abyad, covering an area of 7,850 km2. The systems have produced some 432 monogenetic volcanoes, primarily scoria (cinder) cones, lava shields, and maars. The density distribution of the volcanoes in each system, plotted as eruption points or sites, has a roughly elliptical surface expression, suggesting similar plan-view geometry of the magma sources, here suggested as deep-seated reservoirs. More specifically, the Al Haruj al Aswad magma reservoir has major and minor axes of 210 km and 119 km, respectively, and an area of 19,176 km2, the corresponding figures for the Haruj al Abyad reservoir being 108 km and 74 km, for the axes, and 6209 km2 for the area. We measured 55 lava shields on the AHVP. They are mostly restricted to the northern and southern parts of AHVP and date from late Miocene to (at least) the end of Pleistocene, while some may have been active into Holocene. In fact, although primarily monogenetic, some of the lava shields show evidence of (possibly Holocene) fissure eruptions in the summit parts. The early lava shields tend to be located at the edges of volcanic systems and with greater volumes than later (more central) shields. The average lava shield basal diameter is 4.5 km and height 63 m. There is strong linear correlation between lava shield volume and basal area, the coefficient of determination (R2) being about 0.75. When 22 Holocene Icelandic lava shields are added to the dataset, for comparison, the correlation between volume and basal area becomes R2 = 0.95. Numerical models suggest that the local stress fields favoured rupture and dyke injection at the margins of the source reservoirs during late Miocene - early Pliocene, in agreement with the distribution of the early, large-volume shields.

Improving Middle School Quality in Poor Countries: Evidence from the Honduran "Sistema De Aprendizaje Tutorial"

ERIC Educational Resources Information Center

McEwan, Patrick J.; Murphy-Graham, Erin; Torres Irribarra, David; Aguilar, Claudia; Rápalo, Renán

2015-01-01

This article evaluates the impact and cost-effectiveness of offering an innovative middle school model--the Sistema de Aprendizaje Tutorial (SAT)--to Honduran villages instead of traditional middle schools. We identified a matched sample of villages with either type of school and collected baseline data among primary school graduates eligible to…

Biodiversity Measurement Using Indices Based on Hyperspectral Reflectance on the Coast of Lagos

NASA Astrophysics Data System (ADS)

Omodanisi, E. O.; Salami, A. T.

2013-12-01

Hyperspectral measurements provide explicit measurements which can be used in the analysis of biodiversity change. This study was carried out in the coastal area of Lagos State, Nigeria. The objective of this study was to determine if gasoline seepage affects vegetation species distribution and reflectance; with the view to analyzing the vegetation condition. To evaluate the potential of different reflectance spectroscopy of species, the ASD Handheld2 Spectrometer was used. Three identified impacted plots of 30m by 30m were selected randomly and a control plot established in relatively undisturbed vegetated areas away from but perpendicular to the source of seepage. Each identified plot and the control consisted of five transects and measurement were taken at every 2m with about four reflectance measurement per sample point, to average out differences in reflectance as a result of different leaf angles. The radiance output of the spectrometer was converted into reflectance using the reflectance of a white reference over a standardized white spectralon panel. Indices such as Normalized Differential Vegetation Index, RedEdge Normalized Difference Vegetation Index, Soil Adjusted Vegetation Index, Ratio Vegetation Index and Volgelmann RedEdge Index 1 were calculated to accurately estimate the chlorophyll content in the vegetation within optimal band wavelength. Shannon-Weiner's index, Spearman's rank correlation and Analysis of Variance were used to analyze the data. Cocos nucifera was observed to be the most dominant species with a relative abundance of 47.27% while Ananas comosus recorded the lowest relative abundance of 21.8%. In the control plot, Cocos nucifera had the highest relative abundance of 42.3% and Mangifera indica with the least relative abundance of 16.7%. The relationship between the indices and chlorophyll content of the vegetation were significantly higher at (p>0.01) for all the indices in all the plots; however, RedEdgeNDVI and VOG1 indices had the

Smoking habits, awareness of risks, and attitude towards tobacco control policies among medical students in Lagos, Nigeria.

PubMed

Dania, Michelle G; Ozoh, Obianuju B; Bandele, Emmanuel O

2015-01-01

This study aimed to assess the prevalence of cigarette smoking among medical students, and to determine their level of knowledge regarding risk associated with cigarette smoking and their attitude and behavior towards tobacco control strategies and policies. A stratified random sampling approach was used to select participants. A modified version of the the Global Health Professional Students Survey questionnaire was self-administered. Descriptive statistics were applied and comparisons were done using chi-square test. Multivariate logistic regression was used to obtain the significant determinants of smoking. A P < 0.05 was considered significant. A total of 250 students participated in the study with a response rate of 89.2%. The mean age (years) was 21.4 ± 3. Rate of ever smoking and current smoking was 9.6 and 1.2%, respectively. Age > 21, having a smoking father, and use of alcohol were significantly associated with ever smoking. Knowledge of smoking as a risk for emphysema was 72.8%, coronary artery disease 82.8%, stroke 68.8%, and low birth weight 76.4%. There were 103 (41.2%) students aware of antidepressant usage in smoking cessation. One hundred and ninety-five (78%) offered smoking cessation advice if a smoker had no smoking-related disease and did not seek their opinion about smoking, 68.8% affirmed to having adequate knowledge on smoking cessation, and 56.8% had received formal training on smoking cessation techniques. The ban on cigarette smoking in enclosed public places was supported by 92.4%. The prevalence of current cigarette smoking among medical students in Lagos is relatively low. Gaps exist in the level of knowledge of the students regarding risks of cigarette smoking, tobacco cessation strategies, and in their attitude and behavior towards offering tobacco cessation advice. There is need therefore to include formal training on tobacco control strategies at an early stage in the medical curriculum.

Prevalence and correlates of influenza-A in piggery workers and pigs in two communities in Lagos, Nigeria.

PubMed

Awosanya, Emmanuel Jolaoluwa; Ogundipe, Gabriel; Babalobi, Olutayo; Omilabu, Sunday

2013-01-01

Worldwide, three Influenza-A virus subtypes (H1N1, H1N2 and H3N2) in swine are major public health issues. In Nigeria, the existence of these subtypes in pigs has not been well studied. This study aimed at determining the prevalence and correlates of Influenza-A viruses circulating in piggery workers and pigs in Oke-aro and Goshen communities in Lagos, Nigeria. Nasal swabs were taken from 197 consenting piggery workers and 281 randomly selected pigs to determine the prevalence of Influenza-A (H1, H3, H5) using Reverse Transcriptase Polymerase Chain Reaction test (gene M). An interviewer administered questionnaire was used to collect information on demography, Influenza-A related symptoms experienced, personal hygiene and management practices from the piggery workers. Descriptive statistics was used and chi square test performed at 5% significant level. All piggery workers and pigs' nasal swabs tested negative for Influenza-A viruses, hence, association could not be tested. Mean age of piggery workers was 41 ± 13.6 years and 60% were females. Forty two percent were farm attendants, 38.0% were pig farmers and the rest butchers. Nineteen percent had history of headache; 14.0% had catarrh and cough; 4.0% had sore-throat; 5.0% had diarrhea; while 48.0% had muscle pain at the time of data collection. The mean body temperature for the pig workers was 36.5 ± 0.5 °C. A significant difference (p<0.05) existed among piggery workers who had muscle pains. Piggery workers and pigs in study area were free of Influenza-A (H1, H3, H5) viruses. The current practices of the piggery workers should be encouraged.

Extending health insurance coverage to the informal sector: Lessons from a private micro health insurance scheme in Lagos, Nigeria.

PubMed

Peterson, Lauren; Comfort, Alison; Hatt, Laurel; van Bastelaer, Thierry

2018-04-15

As a growing number of low- and middle-income countries commit to achieving universal health coverage, one key challenge is how to extend coverage to informal sector workers. Micro health insurance (MHI) provides a potential model to finance health services for this population. This study presents lessons from a pilot study of a mandatory MHI plan offered by a private insurance company and distributed through a microfinance bank to urban, informal sector workers in Lagos, Nigeria. Study methods included a survey of microfinance clients, key informant interviews, and a review of administrative records. Demographic, health care seeking, and willingness-to-pay data suggested that microfinance clients, particularly women, could benefit from a comprehensive MHI plan that improved access to health care and reduced out-of-pocket spending on health services. However, administrative data revealed declining enrollment, and key informant interviews further suggested low use of the health insurance plan. Key implementation challenges, including changes to mandatory enrollment requirements, insufficient client education and marketing, misaligned incentives, and weak back-office systems, undermined enrollment and use of the plan. Mandatory MHI plans, intended to mitigate adverse selection and facilitate private insurers' entry into new markets, present challenges for covering informal sector workers, including when distributed through agents such as a microfinance bank. Properly aligning the incentives of the insurer and the agent are critical to effectively distribute and service insurance. Further, an urban environment presents unique challenges for distributing MHI, addressing client perceptions of health insurance, and meeting their health care needs. Copyright © 2018 John Wiley & Sons, Ltd.

The Insecticide Susceptibility Status of Aedes aegypti (Diptera: Culicidae) in Farm and Nonfarm Sites of Lagos State, Nigeria

PubMed Central

Ayorinde, A.; Oboh, B.; Oduola, A.; Otubanjo, O.

2015-01-01

Nigeria is one of the malaria-endemic countries. In Lagos State, Nigeria, various malaria vector control programs including the use of chemical insecticides are currently being implemented. This study was designed to provide information on the susceptibility status of some nontargeted vectors such as Aedes aegypti. Adult Ae. aegypti mosquitoes from two farm sites and a nonfarm site were exposed to World Health Organization test papers impregnated with Deltamethrin (0.05%), Permethrin (0.75%), and DDT (4%) insecticides. The Knockdown time (KdT50 and KdT95) and percentage mortality after 24 h post exposure were determined. In all the exposed mosquito populations to permethrin, mortality rate > 98% (susceptibility) was recorded, whereas mortality rates < 95.8% (resistance) and > 98% (susceptibility) to deltamethrin were observed in the nonfarm site and farm sites mosquito populations, respectively. All the mosquito populations were resistant to DDT in 2 yr. The KdT50 of the populations to DDT increased (60.2–69.6) in one of the farm sites and the nonfarm site (68.9–199.96), while a decrease (243–63.4) in another farm site in 2 yr. Significant difference (P < 0.05) in KdT50 was recorded between the farm and nonfarm sites Ae. aegypti mosquitoes in the second year after exposure to deltamethrin and DDT. An increase in KdT95 after exposure to deltamethrin in the first year was recorded. Higher KdT values and lower mortality rates in Ae. aegypti populations in the nonfarm sites are indications there are existing factors selecting for insecticide resistance outside agricultural use of insecticides. PMID:26106087

Formation of gamma'-Ni3Al via the Peritectoid Reaction: gamma plus beta (+Al2O3) equals gamma'(+Al2O3)

NASA Technical Reports Server (NTRS)

Copland, Evan

2008-01-01

The activities of Al and Ni were measured using multi-cell Knudsen effusion-cell mass spectrometry (multi-cell KEMS), over the composition range 8 - 32 at.%Al and temperature range T = 1400 - 1750 K in the Ni-Al-O system. These measurements establish that equilibrium solidification of gamma'-Ni3Al-containing alloys occurs by the eutectic reaction, L (+ Al2O3) = gamma + beta (+ Al2O3), at 1640 plus or minus 1 K and a liquid composition of 24.8 plus or minus 0.2 at.%Al (at an unknown oxygen content). The {gamma + beta + Al2O3} phase field is stable over the temperature range 1633 - 1640 K, and gamma'-Ni3Al forms via the peritectiod, gamma + beta (+ Al2O3) = gamma'(+ Al2O3), at 1633 plus or minus 1 K. This behavior is inconsistent with the current Ni-Al phase diagram and a new diagram is proposed. This new Ni-Al phase diagram explains a number of unusual steady state solidification structures reported previously and provides a much simpler reaction scheme in the vicinity of the gamma'-Ni3Al phase field.

Directional Solidification and Mechanical Properties of NiAl-NiAlTa Alloys

NASA Technical Reports Server (NTRS)

Johnson, D. R.; Chen, X. F.; Oliver, B. F.; Noebe, R. D.; Whittenberger, J. D.

1995-01-01

Directional solidification of eutectic alloys is a promising technique for producing in-situ composite materials exhibiting a balance of properties. Consequently, the microstructure, creep strength and fracture toughness of directionally solidified NiAl-NiAlTa alloys were investigated. Directional solidification was performed by containerless processing techniques to minimize alloy contamination. The eutectic composition was found to be NiAl-15.5 at% Ta and well-aligned microstructures were produced at this composition. A near-eutectic alloy of NiAl-14.5Ta was also investigated. Directional solidification of the near-eutectic composition resulted in microstructures consisting of NiAl dendrites surrounded by aligned eutectic regions. The off-eutectic alloy exhibited promising compressive creep strengths compared to other NiAl-based intermetallics, while preliminary testing indicated that the eutectic alloy was competitive with Ni-base single crystal superalloys. The room temperature toughness of these two-phase alloys was similar to that of polycrystalline NiAl even with the presence of the brittle Laves phase NiAlTa.

Worldwide Report, Telecommunications Policy, Research and Development, No. 258

DTIC Science & Technology

1983-01-28

3379, December 1979. [20] F. Vatalaro: Caratteristiche di un filtro digitale dpplicato al sistema DME di precisione per MLS, F.U.B., Relazione 43...Spring 1980. [8] F. Chiarini, M. Gori: Possibilitä di miglioramento della precisione di un DME in banda L öfferta da u’n sistema di antenne a...Vecchio, G. Pedrini, F. Vatalaro: Rapporto sul programma per la determinazione delta forma d’onda impulsiva ottima per un sistema DME di precisione in

Theory and X-ray Absorption Spectroscopy for Aluminum Coordination Complexes – Al K-Edge Studies of Charge and Bonding in (BDI)Al, (BDI)AlR2, and (BDI)AlX2 Complexes.

PubMed

Altman, Alison B; Pemmaraju, C D; Camp, Clément; Arnold, John; Minasian, Stefan G; Prendergast, David; Shuh, David K; Tyliszczak, Tolek

2015-08-19

Polarized aluminum K-edge X-ray absorption near edge structure (XANES) spectroscopy and first-principles calculations were used to probe electronic structure in a series of (BDI)Al, (BDI)AlX2, and (BDI)AlR2 coordination compounds (X = F, Cl, I; R = H, Me; BDI = 2,6-diisopropylphenyl-β-diketiminate). Spectral interpretations were guided by examination of the calculated transition energies and polarization-dependent oscillator strengths, which agreed well with the XANES spectroscopy measurements. Pre-edge features were assigned to transitions associated with the Al 3p orbitals involved in metal-ligand bonding. Qualitative trends in Al 1s core energy and valence orbital occupation were established through a systematic comparison of excited states derived from Al 3p orbitals with similar symmetries in a molecular orbital framework. These trends suggested that the higher transition energies observed for (BDI)AlX2 systems with more electronegative X(1-) ligands could be ascribed to a decrease in electron density around the aluminum atom, which causes an increase in the attractive potential of the Al nucleus and concomitant increase in the binding energy of the Al 1s core orbitals. For (BDI)Al and (BDI)AlH2 the experimental Al K-edge XANES spectra and spectra calculated using the eXcited electron and Core-Hole (XCH) approach had nearly identical energies for transitions to final state orbitals of similar composition and symmetry. These results implied that the charge distributions about the aluminum atoms in (BDI)Al and (BDI)AlH2 are similar relative to the (BDI)AlX2 and (BDI)AlMe2 compounds, despite having different formal oxidation states of +1 and +3, respectively. However, (BDI)Al was unique in that it exhibited a low-energy feature that was attributed to transitions into a low-lying p-orbital of b1 symmetry that is localized on Al and orthogonal to the (BDI)Al plane. The presence of this low-energy unoccupied molecular orbital on electron-rich (BDI)Al distinguishes

Development of Al2O3 fiber-reinforced Al2O3-based ceramics.

PubMed

Tanimoto, Yasuhiro; Nemoto, Kimiya

2004-09-01

The purpose of this study was to use a tape casting technique to develop an Al2O3 fiber-reinforced Al2O3-based ceramic material (Al2O3-fiber/Al2O3 composite) into a new type of dental ceramic. The Al2O3-based ceramic used a matrix consisting of 60 wt% Al2O3 powder and 40 wt% SiO2-B2O3 powder. The prepreg sheets of Al2O3-fiber/Al2O3 composite (in which uniaxially aligned Al2O3 fibers were infiltrated with the Al2O3-based matrix) were fabricated continuously using tape casting technique with a doctor blade system. Multilayer preforms of Al2O3-fiber/Al2O3 composite sheets were then sintered at a maximum temperature of 1000 degrees C under an atmospheric pressure in a furnace. The results showed that the shrinkage and bending properties of Al2O3-fiber/Al2O3 composite exceeded those of unreinforced Al2O3--hence demonstrating the positive effects of fiber reinforcement. In conclusion, the tape casting technique has been utilized to successfully develop a new type of dental ceramic material.

NiAl-base composite containing high volume fraction of AlN for advanced engines

NASA Technical Reports Server (NTRS)

Hebsur, Mohan (Inventor); Whittenbeger, John D. (Inventor); Lowell, Carl F. (Inventor)

1994-01-01

A particulate reinforced NiAl-AlN composite alloy has a NiAl matrix and greater than about 13 volume percent fine particles of AlN within the matrix. The particles preferably have a diameter from about 15 nanometers to about 50 nanometers. The particulate reinforced NiAl-AlN composite alloy may be prepared by cryomilling prealloyed NiAl in liquid nitrogen using grinding media having a diameter of from about 2 to 6 mm at an impeller speed of from about 450 RPM to about 800 RPM. The cryomilling may be done for a duration of from about 4 hours to about 20 hours to obtain a cryomilled powder. The cryomilled powder may be consolidated to form the particulate reinforced NiAl-AlN composite alloy. The particulate reinforced alloy can further include a toughening alloy. The toughening alloy may include NiCrAlY, FeCrAlY, and FeAl.

Molecular dynamics study of Al and Ni 3Al sputtering by Al clusters bombardment

NASA Astrophysics Data System (ADS)

Zhurkin, Eugeni E.; Kolesnikov, Anton S.

2002-06-01

The sputtering of Al and Ni 3Al (1 0 0) surfaces induced by impact of Al ions and Al N clusters ( N=2,4,6,9,13,55) with energies of 100 and 500 eV/atom is studied at atomic scale by means of classical molecular dynamics (MD). The MD code we used implements many-body tight binding potential splined to ZBL at short distances. Special attention has been paid to model dense cascades: we used quite big computation cells with lateral periodic and damped boundary conditions. In addition, long simulation times (10-25 ps) and representative statistics (up to 1000 runs per each case) were considered. The total sputtering yields, energy and time spectrums of sputtered particles, as well as preferential sputtering of compound target were analyzed, both in the linear and non-linear regimes. The significant "cluster enhancement" of sputtering yield was found for cluster sizes N⩾13. In parallel, we estimated collision cascade features depending on cluster size in order to interpret the nature of observed non-linear effects.

Nb/Al-AlOx/Nb Edge Junctions for Distributed Mixers

NASA Astrophysics Data System (ADS)

Amos, R. S.; Lichtenberger, A. W.; Tong, C. E.; Blundell, R.; Pan, S.-K.; Kerr, A. R.

We have fabricated high quality Nb/Al-oxide/Al/Nb edge junctions using a Nb/SiO/sub 2/ bi-layer film as the base electrode, suitable for use as traveling wave mixers. An edge is cut in the bi-layer with an ion gun at a 45 degree angle using a photoresist mask. The wafer is then cleaned in-situ with a physical ion gun clean followed by the deposition of a thin Al (a1) film, which is then thermally oxidized, an optional second Al (a2) layer, and a Nb counter electrode. It was found that devices with an a2 layer resulted in superior electrical characteristics, though proximity effects increased strongly with a2 thickness. The counter electrode is defined with an SF/sub 6/+N/sub 2/ reactive ion etch, using the Al barrier layer as an etch stop. The Al barrier layer is then either removed with an Al wet etch to isolate the individual devices, or the devices are separated with an anodization process. Various ion gun cleaning conditions have been examined; in addition, both wet and plasma etch bi-layer edge surface pre-treatments were investigated. It was found that edge junctions with large widths (i.e., those more suitable for traveling wave mixers) typically benefited more from such treatments. Initial receiver results at 260 GHz have yielded a DSB noise temperature of 60 K.

Photoelectrical, photophysical and photocatalytic properties of Al based MOFs: MIL-53(Al) and MIL-53-NH{sub 2}(Al)

DOE Office of Scientific and Technical Information (OSTI.GOV)

An, Yang; Li, Huiliang; Liu, Yuanyuan, E-mail: yyliu@sdu.edu.cn

Two Al based MOFs (MIL-53(Al) and MIL-53-NH{sub 2} (Al)) were synthesized, and their photoelectrical, photophysical and photocatalytic properties towards oxygen evolution from water were investigated. Different from the ligand to metal charge transfer process previously reported, we proposes a new photocatalytic mechanism based on electron tunneling according to the results of theoretical calculation, steady state and time resolved fluorescence spectra. The organic linkers absorb photons, giving rise to electrons and holes. Then, the photogenerated electrons tunnel through the AlO{sub 6}-octahedra, which not only inhibit the recombination of photogenerated charge carriers, but also is a key factor to the photocatalytic activitymore » of Al based MOFs. - Graphical abstract: The photoelectrical, photophysical and photocatalytic properties towards oxygen evolution from water of two Al based MOFs were investigated. A new photocatalytic mechanism was proposed based on electron tunneling according to the results of both theoretical calculation and steady state, time resolved fluorescence spectra. The electron tunneling process not only inhibit the recombination of photogenerated charge carriers, but also is a key factor to the photocatalytic activity of Al based MOFs.« less

U-Th and 10Be constraints on sediment recycling in proglacial settings, Lago Buenos Aires, Patagonia

NASA Astrophysics Data System (ADS)

Cogez, Antoine; Herman, Frédéric; Pelt, Éric; Reuschlé, Thierry; Morvan, Gilles; Darvill, Christopher M.; Norton, Kevin P.; Christl, Marcus; Märki, Lena; Chabaux, François

2018-03-01

The estimation of sediment transfer times remains a challenge to our understanding of sediment budgets and the relationships between erosion and climate. Uranium (U) and thorium (Th) isotope disequilibria offer a means of more robustly constraining sediment transfer times. Here, we present new uranium and thorium disequilibrium data for a series of nested moraines around Lago Buenos Aires in Argentine Patagonia. The glacial chronology for the area is constrained using in situ cosmogenic 10Be analysis of glacial outwash. Sediment transfer times within the periglacial domain were estimated by comparing the deposition ages of moraines to the theoretical age of sediment production, i.e., the comminution age inferred from U disequilibrium data and recoil loss factor estimates. Our data show first that the classical comminution age approach must include weathering processes accounted for by measuring Th disequilibrium. Second, our combined data suggest that the pre-deposition history of the moraine sediments is not negligible, as evidenced by the large disequilibrium of the youngest moraines despite the equilibrium of the corresponding glacial flour. Monte Carlo simulations suggest that weathering was more intense before the deposition of the moraines and that the transfer time of the fine sediments to the moraines was on the order of 100-200 kyr. Long transfer times could result from a combination of long sediment residence times in the proglacial lake (recurrence time of a glacial cycle) and the remobilization of sediments from moraines deposited during previous glacial cycles. 10Be data suggest that some glacial cycles are absent from the preserved moraine record (seemingly every second cycle), supporting a model of reworking moraines and/or fluctuations in the extent of glacial advances. The chronological pattern is consistent with the U-Th disequilibrium data and the 100-200 kyr transfer time. This long transfer time raises the question of the proportion of freshly

Medio ambiente y cáncer pediátrico en la Región de Murcia (España): integrando la historia clínica medioambiental en un sistema de información geográfica

PubMed Central

Ortega-García, J.A.; López-Hernández, F.A.; Sobrino-Najul, E.; Febo, I.; Fuster-Soler, J.L.

2016-01-01

Introducción Medio Ambiente y Cáncer Pediátrico (CP) en la Región de Murcia (RM) es un proyecto de investigación, cuya principal meta es el desarrollo de una cuidadosa historia ambiental pediátrica (HAP) y el uso de sistemas de información geográfica (SIG) para crear mapas de incidencia y analizar la distribución geográfica del CP en la RM. El objetivo es presentar la metodología, el estudio descriptivo y los primeros resultados sobre la incidencia espacial y temporal del CP en la RM (España). Material y métodos Estudio descriptivo y de georreferenciación de todos los casos de CP menores de 15 años, diagnosticados entre el 1 de enero de 1998 y el 31 de diciembre de 2009. Se han asociado a cada caso tres direcciones postales, durante el embarazo, en el período posnatal y en el momento del diagnóstico. También se han utilizado las siguientes variables: sexo, fechas de nacimiento y diagnóstico y el diagnóstico patológico. Resultados No se observa un incremento en la tendencia de la incidencia del CP. La tasa cruda de incidencia fue de 14,3 casos por 100.000 niños menores de 15 años. La razón de incidencia estandarizada es más elevada en el noroeste de la RM. El 30% tienen un domicilio previo al diagnóstico distinto al del embarazo. Conclusiones La integración de la información temporal y espacial de la HAP en un SIG permitirá la identificación y el estudio de conglomerados espacio-temporales a través de un sistema de vigilancia medioambiental que ayude a ponderar la importancia de los factores de riesgo asociados. PMID:21315667

Moto del Sole intorno al baricentro del sistema solare

NASA Astrophysics Data System (ADS)

Piovan, Luciano; Milani, Franco

2006-06-01

The paper discusses the Sun's motion around the barycentre of the Solar System determined by the ever-changing dispositon of the planets over approximately 2000 years. Files of high-quality data taken from international sites were used in common personal computers. The Sun shows a repetitive behaviour, where an apocycle (ApC, decennial period in which the Sun moves very far from the barycentre) is followed by a pericycle (PeC, decennial period in which the Sun moves very near the barycentre) and by another ApC, etc. Periodicities exist in the short period (supercycles, SpC, lasting about 40 years and made of two sequences ApC-PeC, each lasting 20 years), in the mean period (phases comprising a sequence of 4 to 5 SpC, then lasting approximately 160 or 200 years respectively, mean value 180 years), and in the long period (hypercycles, IpC, consisting of two phases, lasting approximately 360 or 400 years). During one phase, the successive ApCs start opposed to each other in ecliptical coordinates and end nearly superimposed; during the following phase the ApCs start superimposed one over the other and end opposed to each other in ecliptical coordinates. The phase length, whose mean value is about 180 years, is very near the modulation of the maxima of the sunspot cycle (178.7 years). The periodicities found are modulated mainly by the alignment of Jupiter, or by both Jupiter and Saturn, with the Sun and the barycentre of the Solar System.

Oxidation of Al2O3 continuous fiber-reinforced/NiAl composites

NASA Technical Reports Server (NTRS)

Doychak, J.; Nesbitt, J. A.; Noebe, R. D.; Bowman, R. R.

1992-01-01

The 1200 C and 1300 C isothermal and cyclic oxidation behavior of Al2O3 continuous fiber-reinforced/NiAl composites were studied. Oxidation resulted in formation of Al2O3 external scales in a similar manner as scales formed on monolithic NiAl. The isothermal oxidation of an Al2O3/NiAl composite resulted in oxidation of the matrix along the fiber/matrix interface near the fiber ends. This oxide acted as a wedge between the fiber and the matrix, and, under cyclic oxidation conditions, led to further oxidation along the fiber lengths and eventual cracking of the composite. The oxidation behavior of composites in which the Al2O3 fibers were sputter coated with nickel prior to processing was much more severe. This was attributed to open channels around the fibers which formed during processing, most likely as a result of the diffusion of the nickel coating into the matrix.

Structure of oxides prepared by decomposition of layered double Mg–Al and Ni–Al hydroxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cherepanova, Svetlana V.; Novosibirsk State University, Novosibirsk; Leont’eva, Natalya N., E-mail: n_n_leonteva@list.ru

2015-05-15

Abstracts: Thermal decomposition of Mg–Al and Ni–Al layered double hydroxides LDH at temperatures lower than 800 °C leads to the formation of oxides with different structures. Mg–Al oxide has a very defective structure and consists of octahedral layers as in periclase MgO and mixed octahedral–tetrahedral layers as in spinel MgAl{sub 2}O{sub 4}. Mixed Ni–Al oxide has a sandwich-like structure, consisting of a core with Al-doped NiO-like structure and some surface layers with spinel NiAl{sub 2}O{sub 4} structure epitaxial connected with the core. Suggested models were verified by simulation of X-ray diffraction patterns using DIFFaX code, as well as HRTEM, IR-,more » UV-spectroscopies, and XPS. - Graphical abstract: In the Mg–Al layered double hydroxide Al{sup 3+} ions migrate into interlayers during decomposition. The Mg–Al oxide represents sequence of octahedral and octahedral–tetrahedral spinel layers with vacancies. The Ni–Al oxide has a sandwich-like structure with NiO-like core and surface spinel layers as a result of migration of Al{sup 3+} ions on the surface. The models explain the presence and absence of “memory effect” for the Mg–Al and Ni–Al oxides, respectively. - Highlights: • We study products of Mg(Ni)–Al LDH decomposition by calcination at 500(400)–800 °C. • In Mg–Al/Ni–Al LDH Al ions migrate into interlayers/on the surface during decomposition. • Mg–Al oxide represents sequence of periclase- and spinel-like layers with vacancies. • Ni–Al oxide has a sandwich-like structure with NiO-like core and surface spinel layers. • The models explain the presence/absence of “memory effect” for Mg–Al/Ni–Al oxides.« less

Correlations between psychopathology and self-reported quality of life among adolescents in youth correctional facilities in Lagos, Nigeria: A short report.

PubMed

Atilola, Olayinka; Ola, Bolanle; Abiri, Gbonjubola; Adewuya, Abiodun O

2018-02-01

The relationship between psychopathology and quality of life (QoL) and well-being among young incarcerated offenders has hardly been explored. Our aim was to test the hypothesis that higher self-rated psychopathology would be associated with lower QoL among adolescents resident within youth correctional facilities in Lagos. Psychopathology was assessed using the Strength and Difficulty Questionnaire (SDQ), while QoL was measured by using the Paediatric Quality of Life. One hundred and sixty-five adolescents completed the study, mostly boys (n = 124; 75%) with a mean age of 14.3 ± 2.1 years. Nearly, a fifth (30, 18%) of respondents had abnormal total SDQ scores (≥17), suggestive of definite psychiatric disorder, while another 44 (27%) had highly probable psychopathology (total SDQ scores 15-16). There was strong negative correlation (r = -0.51, p < 0.001) between total SDQ scores and overall self-reported QoL among respondents. Although we were unable to infer direction of relationship between psychopathology and QoL among these adolescents, it is plausible to suppose that treatment of mental health problems could have a positive impact on rehabilitation and reintegration. Given the rate of likely psychopathology, mental health screening within young offender institutions should be routine, and followed, as necessary with full assessment and resultant treatment. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

FACTORS ASSOCIATED WITH TB/HIV CO-INFECTION AMONG DRUG SENSITIVE TUBERCULOSIS PATIENTS MANAGED IN A SECONDARY HEALTH FACILITY IN LAGOS, NIGERIA.

PubMed

Adejumo, Olusola A; Daniel, Olusoji J; Otesanya, Andrew F; Adegbola, Adebukola A; Femi-Adebayo, Temitope; Bowale, Abimbola; Adesola, Sunday; Kuku, Olugbenga O; Otemuyiwa, Kehinde O; Oladega, Shafaatu N; Johnson, Eze O; Falana, Ayodeji A; Dawodu, Olusola; Owuna, Henry; Osoba, Ganiyat; Dacosta, Adetokunbo

2017-01-01

This study assessed factors associated with TB/HIV co-infection among TB patients managed in a secondary health facility in Lagos Nigeria. A retrospective review of treatment cards of patients seen at a secondary referral hospital between January 1 2014 and December 31 2014 was conducted. Treatment outcomes and factors associated with TB/HIV co-infection were assessed. Of the 334 records of patients reviewed, the proportion of patients with TB/HIV co-infection was 21.6%. The odds of having TB/HIV co-infection was 2.7 times higher among patients above 40 years than patients less than 25 years (AOR 2.7 95% CI 1.1 - 6.5, p =0.030). In addition, the odds of having TB/HIV co-infection was 3.3 higher among extra-pulmonary TB cases (AOR 3.3; 95% CI 1.2 - 9.5; p = 0.026) and 2.1 times higher among retreated patients (AOR 2.1; 95% CI 1.1 - 3.9; p = 0.017) than pulmonary TB and new patients respectively. The chance of having TB/HIV co-infection was 2.7-fold more in patients with poor treatment outcomes than patients with treatment success (AOR 2.7; 95%CI 1.3 - 5.4; p =0.006). TB/HIV co-infection rate was high in the study area. There is need to put measures in place to improve treatment outcomes of TB/HIV co-infected patients.

Molecular structure of Mg-Al, Mn-Al and Zn-Al halotrichites-type double sulfates--an infrared spectroscopic study.

PubMed

Palmer, Sara J; Frost, Ray L

2011-05-01

Near infrared (NIR), X-ray diffraction (XRD) and infrared (IR) spectroscopy have been applied to halotrichites of the formula MgAl(2)(SO(4))(4)·22H(2)O, MnAl(2)(SO(4))(4)·22H(2)O and ZnAl(2)(SO(4))(4)·22H(2)O. Comparison of the halotrichites in different spectral regions has shown that the incorporation of a divalent transition metal into the halotrichite structure causes a shift in OH stretching band positions to lower wavenumbers. Therefore, an increase of the hydrogen bond strength of the bonded water is observed for divalent cations with a larger molecular mass. XRD has confirmed the formation of halotrichite for all three samples and characteristic peaks of halotrichite have been identified for each halotrichite-type compound. It has been observed that Mg-Al and Mn-Al halotrichite are very similar in structure, while Zn-Al showed several differences particularly in the NIR spectra. This work has shown that compounds with halotrichite structures can be synthesised and characterised by infrared and NIR spectroscopy. Copyright © 2011 Elsevier B.V. All rights reserved.

Mechanisms of elevated-temperature deformation in the B2 aluminides NiAl and CoAl

NASA Technical Reports Server (NTRS)

Yaney, D. L.; Nix, W. D.

1988-01-01

A strain rate change technique, developed previously for distinguishing between pure-metal and alloy-type creep behavior, was used to study the elevated-temperature deformation behavior of the intermetallic compounds NiAl and CoAl. Tests on NiAl were conducted at temperatures between 1100 and 1300 K while tests on CoAl were performed at temperatures ranging from 1200 to 1400 K. NiAl exhibits pure-metal type behavior over the entire temperature range studied. CoAl, however, undergoes a transition from pure-metal to alloy-type deformation behavior as the temperature is decreased from 1400 to 1200 K. Slip appears to be inherently more difficult in CoAl than in NiAl, with lattice friction effects limiting the mobility of dislocations at a much higher tmeperature in CoAl than in NiAl. The superior strength of CoAl at elevated temperatures may, therefore, be related to a greater lattice friction strengthening effect in CoAl than in NiAl.

CVD Fiber Coatings for Al2O3/NiAl Composites

NASA Technical Reports Server (NTRS)

Boss, Daniel E.

1995-01-01

While sapphire-fiber-reinforced nickel aluminide (Al2O3/NiAl) composites are an attractive candidate for high-temperature structures, the significant difference in the coefficient of thermal expansion between the NiAl matrix and the sapphire fiber creates substantial residual stresses in the composite. This study seeks to produce two fiber-coating systems with the potential to reduce the residual stresses in the sapphire/NiAl composite system. Chemical vapor deposition (CVD) was used to produce both the compensating and compliant-fiber coatings for use in sapphire/NiAl composites. A special reactor was designed and built to produce the FGM and to handle the toxic nickel precursors. This process was successfully used to produce 500-foot lengths of fiber with coating thicknesses of approximately 3 microns, 5 microns, and 10 microns.

Dietary practices and nutritional status of under-five children in rural and urban communities of Lagos State, Nigeria.

PubMed

Senbanjo, Idowu O; Olayiwola, Ibiyemi O; Afolabi, Wasiu A O

2016-01-01

Evidence shows that urban children generally have a better nutritional status than their rural counterparts. However, data establishing whether this difference in prevalence of undernutrition could be ascribed to difference in dietary practices are few. The aim of this study was to compare dietary practices and nutritional status of children in rural and urban communities of Lagos State, Nigeria. This was a comparative-analytical study conducted using the multistage sampling technique to select the study cases. A total of 300 mother-child pairs were studied, including 150 each from rural and urban communities. Data collected include demographics, socioeconomic characteristics, feeding practices and anthropometric measurements of the participants. Food intake data were collected using 24-h dietary recall. Malnutrition in children was determined by calculating the prevalence of low height-for-age (stunting), low weight-for-age (underweight), and low weight-for-height (wasting) using the World Health Organization cutoff points. The prevalence of exclusive breastfeeding for 6 months (25.3% vs. 28.7%; P = 0.516), use of formula feeds (48.7% vs. 44%; P = 0.077), and mean age of child at introduction of semisolid foods (7.54 ± 4.0 months vs. 8.51 ± 7.3 months; P = 0.117) were not significantly different between urban and rural communities. The diversity of food choices and frequencies of consumption were similar between urban and rural communities. However, prevalence levels of underweight and stunted children were significantly higher in rural than that of urban communities (19.4% vs. 9.3%, P < 0.001 and 43.3% vs. 12.6%, P < 0.001, respectively). Other risk factors besides inappropriate feeding practices need to be considered for higher prevalence of undernutrition among children in rural communities.

Dietary practices and nutritional status of under-five children in rural and urban communities of Lagos State, Nigeria

PubMed Central

Senbanjo, Idowu O.; Olayiwola, Ibiyemi O.; Afolabi, Wasiu A. O.

2016-01-01

Background: Evidence shows that urban children generally have a better nutritional status than their rural counterparts. However, data establishing whether this difference in prevalence of undernutrition could be ascribed to difference in dietary practices are few. Objective: The aim of this study was to compare dietary practices and nutritional status of children in rural and urban communities of Lagos State, Nigeria. Methods: This was a comparative-analytical study conducted using the multistage sampling technique to select the study cases. A total of 300 mother–child pairs were studied, including 150 each from rural and urban communities. Data collected include demographics, socioeconomic characteristics, feeding practices and anthropometric measurements of the participants. Food intake data were collected using 24-h dietary recall. Malnutrition in children was determined by calculating the prevalence of low height-for-age (stunting), low weight-for-age (underweight), and low weight-for-height (wasting) using the World Health Organization cutoff points. Results: The prevalence of exclusive breastfeeding for 6 months (25.3% vs. 28.7%; P = 0.516), use of formula feeds (48.7% vs. 44%; P = 0.077), and mean age of child at introduction of semisolid foods (7.54 ± 4.0 months vs. 8.51 ± 7.3 months; P = 0.117) were not significantly different between urban and rural communities. The diversity of food choices and frequencies of consumption were similar between urban and rural communities. However, prevalence levels of underweight and stunted children were significantly higher in rural than that of urban communities (19.4% vs. 9.3%, P < 0.001 and 43.3% vs. 12.6%, P < 0.001, respectively). Conclusions: Other risk factors besides inappropriate feeding practices need to be considered for higher prevalence of undernutrition among children in rural communities. PMID:27942096

Study on Mg/Al Weld Seam Based on Zn–Mg–Al Ternary Alloy

PubMed Central

Liu, Liming; Liu, Fei; Zhu, Meili

2014-01-01

Based on the idea of alloying welding seams, a series of Zn–xAl filler metals was calculated and designed for joining Mg/Al dissimilar metals by gas tungsten arc (GTA) welding. An infrared thermography system was used to measure the temperature of the welding pool during the welding process to investigate the solidification process. It was found that the mechanical properties of the welded joints were improved with the increasing of the Al content in the Zn–xAl filler metals, and when Zn–30Al was used as the filler metal, the ultimate tensile strength could reach a maximum of 120 MPa. The reason for the average tensile strength of the joint increasing was that the weak zone of the joint using Zn–30Al filler metal was generated primarily by α-Al instead of MgZn2. When Zn–40Al was used as the filler metal, a new transition zone, about 20 μm-wide, appeared in the edge of the fusion zone near the Mg base metal. Due to the transition zones consisting of MgZn2- and Al-based solid solution, the mechanical property of the joints was deteriorated. PMID:28788508

Chemical failure modes of AlQ3-based OLEDs: AlQ3 hydrolysis.

PubMed

Knox, John E; Halls, Mathew D; Hratchian, Hrant P; Schlegel, H Bernhard

2006-03-28

Tris(8-hydroxyquinoline)aluminum(III), AlQ3, is used in organic light-emitting diodes (OLEDs) as an electron-transport material and emitting layer. The reaction of AlQ3 with trace H2O has been implicated as a major failure pathway for AlQ3-based OLEDs. Hybrid density functional calculations have been carried out to characterize the hydrolysis of AlQ3. The thermochemical and atomistic details for this important reaction are reported for both the neutral and oxidized AlQ3/AlQ3+ systems. In support of experimental conclusions, the neutral hydrolysis reaction pathway is found to be a thermally activated process, having a classical barrier height of 24.2 kcal mol(-1). First-principles infrared and electronic absorption spectra are compared to further characterize AlQ3 and the hydrolysis pathway product, AlQ2OH. The activation energy for the cationic AlQ3 hydrolysis pathway is found to be 8.5 kcal mol(-1) lower than for the neutral reaction, which is significant since it suggests a role for charge imbalance in promoting chemical failure modes in OLED devices.

Risk Perception and Correlates of Tobacco Use among Young People Outside of Formal School Settings in Lagos State, Nigeria.

PubMed

Odukoya, O O; Dada, M R; Olubodun, T; Igwilo, U A; Ayo-Yusuf, O A

2016-01-01

Tobacco use among youth is a major public health problem. Youth outside of formal school settings are often understudied but may be at increased risk. A descriptive cross- sectional study was carried out among 326 young people aged 15-24 years in four randomly selected motor parks in Lagos state. Interviewer-administered questionnaires were used to collect data. The mean age of the respondents was 21.0±2.3yrs. Many 252 (77.3%) dropped out before the end of the third year of secondary schooling. The majority were aware that active (78.2%), and passive smoking (77.3%) are harmful to health. Nearly two-thirds of the respondents disagreed with an outright ban of cigarettes (63.2%) and restriction of cigarette sales to persons below 18 years (67.9%) while 254 (66.8%) supported a ban on tobacco smoking in enclosed public places. One hundred and fifty (46.0%) respondents had experimented with smoking of which 106 (32.5%) had progressed to become current smokers. Half of the current smokers, 54 (50.9%), felt the need for a cigarette first thing in the morning. A multivariate analysis for smoking initiation, showed that for every increasing year of age, respondents were 1.08 times more likely to have initiated cigarette smoking; males and respondents who lived alone or with peers were 2.34 times and 1.77 times more likely to have initiated smoking respectively; those who consume alcohol and marijuana were 7.27 and 1.89 times respectively more likely to have initiated smoking while those who consumed alcohol were 6.17 times more likely to be current smokers.

Optical, structural, and nuclear scientific studies of AlGaN with high Al composition

NASA Astrophysics Data System (ADS)

Lin, Tse Yang; Chung, Yee Ling; Li, Lin; Yao, Shude; Lee, Y. C.; Feng, Zhe Chuan; Ferguson, Ian T.; Lu, Weijie

2010-08-01

AlGaN epilayers with higher Al-compositions were grown by Metalorganic Chemical Vapor Deposition (MOCVD) on (0001) sapphire. Trimethylgallium (TMGa), trimethylaluminium (TMAl) and NH3 were used as the source precursors for Ga, Al, and N, respectively. A 25 nm AlN nucleation layer was first grown at low-temperature of 590 °C at 300 Torr. Followed, AlxGa1-xN layers were grown at 1080 °C on low-temperature AlN nucleation layers. The heterostructures were characterized by a series of techniques, including x-ray diffraction (XRD), Rutherford backscattering (RBS), photoluminescence (PL), scanning electron microscopy (SEM) and Raman scattering. Precise Al compositions were determined through XRD, RBS, and SEM combined measurements. Room Temperature Raman Scattering spectra shows three major bands from AlGaN alloys, which are AlN-like, A1 longitudinal optical (LO) phonon modes, and E2 transverse optical (TO) band, respectively, plus several peak comes from the substrate. Raman spectral line shape analysis lead to an optical determination of the electrical property free carrier concentration of AlGaN. The optical properties of AlGaN with high Al composition were presented here.

Epitaxial growth of Al9Ir2 intermetallic compound on Al(100): Mechanism and interface structure

NASA Astrophysics Data System (ADS)

Kadok, J.; Pussi, K.; Šturm, S.; Ambrožič, B.; Gaudry, É.; de Weerd, M.-C.; Fournée, V.; Ledieu, J.

2018-04-01

The adsorption of Ir adatoms on Al(100) has been investigated under various exposures and temperature conditions. The experimental and theoretical results reveal a diffusion of Ir adatoms within the Al(100) surface selvedge already at 300 K. Above 593 K, two domains of a (√{5 }×√{5 }) R 26 .6∘ phase are identified by low energy electron diffraction (LEED) and scanning tunneling microscopy measurements. This phase corresponds to the initial growth of an Al9Ir2 compound at the Al(100) surface. The Al9Ir2 intermetallic domains are terminated by bulklike pure Al layers. The structural stability of Al9Ir2 (001) grown on Al(100) has been analyzed by density functional theory based calculations. Dynamical LEED analysis is consistent with an Ir adsorption leading to the growth of an Al9Ir2 intermetallic compound. We propose that the epitaxial relationship Al9Ir2(001 ) ∥Al (100) and Al9Ir2[100 ] ∥Al [031 ]/[013 ] originates from a matching of Al atomic arrangements present both on Al(100) and on pure Al(001) layers present in the Al9Ir2 compound. Finally, the interface between Al9Ir2 precipitates and the Al matrix has been characterized by transmission electron microscopy measurements. The cross-sectional observations are consistent with the formation of Al9Ir2 (001) compounds. These measurements indicate an important Ir diffusion within Al(100) near the surface region. The coherent interface between Al9Ir2 and the Al matrix is sharp.

Evaluations of groundwater contamination by leachates around Olusosun open dumpsite in Lagos metropolis, southwest Nigeria.

PubMed

Aboyeji, Olatunji Sunday; Eigbokhan, Stephen Femi

2016-12-01

A major cause of groundwater pollution in urban areas is contamination by leachates emanating from municipal solid waste dumpsites. The study evaluated the quality of water of selected boreholes and wells around Olusosun open solid waste dumpsite in Lagos metropolis, using water quality index (WQI) rating and geospatial techniques. Water samples were randomly collected from fifteen boreholes and five wells downslopes of the dumpsite. The samples were analysed for the physico-chemical parameters and heavy metals. Factor Analysis was employed to analyse the information content of the water quality indicators to determine their appropriateness for indexing. The spatial distribution of the WQIs determined using Inverse Distance Weighting (IDW) interpolation procedure. Results showed that the waters were generally acidic with 85% of pH values below the range suggested by WHO for drinking water. All samples contained concentration of dissolved oxygen (DO) in quantities higher than the recommended limit of 2.0 mg/l (average = 4.97 mg/l), while 40% of the samples contained concentration of K above the recommended limit. The concentration of heavy metals was generally low. The major cations (Mg, Na, and K) were highly positively correlated, and were positively correlated with pH, TA, TAL, TH and Cl. Negative correlations were observed between TDS, NO3(-) and PO4(3-); NO3(-) and Ag; and DO with the heavy metals. Eighteen parameters consisting of pH, EC, TDS, TA, TAL, TH, Cl, NO3(-), PO4(3-), Mg, Na, K, Zn, Mn, Fe, Cd, Ag and Pb were found to be the main indicators of groundwater pollution caused by landfill leachate percolation. Evaluation of the WQIs indicated that 35% of the water samples were unsuitable for consumption, while 15%, 15% and 35% were in the good, very good and excellent categorises, respectively. The degree of suitability of the borehole and well waters was closely related to proximity to the dumpsite. It is imperative that appropriate remediation

Formation of gamma(sup prime)-Ni3Al via the Peritectoid Reaction: gamma + beta (+ Al2O3)=gamma(sup prime)(+ Al2O3)

NASA Technical Reports Server (NTRS)

Copeland, Evan

2008-01-01

The activities of Al and Ni were measured using multi-cell Knudsen effusion-cell mass spectrometry (multi-cell KEMS), over the composition range 8-32 at.%Al and temperature range T=1400-1750 K in the Ni-Al-O system. These measurements establish that equilibrium solidification of gamma(sup prime)-Ni3Al-containing alloys occurs by the eutectic reaction, L (+ Al2O3)=gamma + Beta(+ Al2O3), at 1640 +/- 1 K and a liquid composition of 24.8 +/- 0.2 at.%al (at an unknown oxygen content). The {gamma + Beta (+Al2O3} phase field is stable over the temperature range 1633-1640 K, and gamma(sup prime)-Ni3Al forms via the peritectoid, gamma + Beta (+ Al2O3)=gamma(sup prime) (+ Al2O3), at 1633 +/- 1 K. This behavior is consistent with the current Ni-Al phase diagram and a new diagram is proposed. This new Ni-Al phase diagram explains a number of unusual steady-state solidification structures reported previously and provides a much simpler reaction scheme in the vicinity of the gamma(sup prime)-Ni2Al phase field.

Chemical trend of superconducting transition temperature in hole-doped delafossite of CuAlO2, AgAlO2 and AuAlO2

NASA Astrophysics Data System (ADS)

Nakanishi, Akitaka; Katayama-Yoshida, Hiroshi

2012-12-01

We have performed the first-principles calculations about the superconducting transition temperature Tc of hole-doped delafossite CuAlO2, AgAlO2 and AuAlO2. Calculated Tc are about 50 K (CuAlO2), 40 K (AgAlO2) and 3 K(AuAlO2) at maximum in the optimum hole-doping concentration. The low Tc of AuAlO2 is attributed to the weak electron-phonon interaction caused by the low covalency and heavy atomic mass.

Atomistic simulation of Al-graphene thin film growth on polycrystalline Al substrate

NASA Astrophysics Data System (ADS)

Zhang, Lan; Zhu, Yongchao; Li, Na; Rong, Yan; Xia, Huimin; Ma, Huizhong

2018-03-01

The growth of Al-Graphene composite coatings on polycrystalline Al substrate was investigated by using classical molecular dynamics (MD) simulations. Unlike the diffusion behaviors on single crystal surface, most of adatoms were easily bound by the steps on polycrystalline Al surface, owing to the local accelerated energy. Both Ehrlich-Schwoebel (ES) barriers and the steering effect backed up the volmer-weber growth mode, which was consistent with the dynamic growth process observed in the deposit. The morphology of composite coatings was significantly affected by graphene flakes. Enrichment of graphene flakes gave rise to an increase of the local thickness, and graphene flakes only existed in Al grain boundaries. The size of Al grains in the composite coating visibly decreased when compared with that in the pure Al coating. This grain refinement and the mechanical property can be reinforced by the increase of graphene flakes.

Insulator-semiconductor interface fixed charges in AlGaN/GaN metal-insulator-semiconductor devices with Al2O3 or AlTiO gate dielectrics

NASA Astrophysics Data System (ADS)

Le, Son Phuong; Nguyen, Duong Dai; Suzuki, Toshi-kazu

2018-01-01

We have investigated insulator-semiconductor interface fixed charges in AlGaN/GaN metal-insulator-semiconductor (MIS) devices with Al2O3 or AlTiO (an alloy of Al2O3 and TiO2) gate dielectrics obtained by atomic layer deposition on AlGaN. Analyzing insulator-thickness dependences of threshold voltages for the MIS devices, we evaluated positive interface fixed charges, whose density at the AlTiO/AlGaN interface is significantly lower than that at the Al2O3/AlGaN interface. This and a higher dielectric constant of AlTiO lead to rather shallower threshold voltages for the AlTiO gate dielectric than for Al2O3. The lower interface fixed charge density also leads to the fact that the two-dimensional electron concentration is a decreasing function of the insulator thickness for AlTiO, whereas being an increasing function for Al2O3. Moreover, we discuss the relationship between the interface fixed charges and interface states. From the conductance method, it is shown that the interface state densities are very similar at the Al2O3/AlGaN and AlTiO/AlGaN interfaces. Therefore, we consider that the lower AlTiO/AlGaN interface fixed charge density is not owing to electrons trapped at deep interface states compensating the positive fixed charges and can be attributed to a lower density of oxygen-related interface donors.

26Al- 26Mg and 207Pb- 206Pb systematics of Allende CAIs: Canonical solar initial 26Al/ 27Al ratio reinstated

NASA Astrophysics Data System (ADS)

Jacobsen, Benjamin; Yin, Qing-zhu; Moynier, Frederic; Amelin, Yuri; Krot, Alexander N.; Nagashima, Kazuhide; Hutcheon, Ian D.; Palme, Herbert

2008-07-01

The precise knowledge of the initial 26Al/ 27Al ratio [( 26Al/ 27Al) 0] is crucial if we are to use the very first solid objects formed in our Solar System, calcium-aluminum-rich inclusions (CAIs) as the "time zero" age-anchor and guide future work with other short-lived radio-chronometers in the early Solar System, as well as determining the inventory of heat budgets from radioactivities for early planetary differentiation. New high-precision multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) measurements of 27Al/ 24Mg ratios and Mg-isotopic compositions of nine whole-rock CAIs (six mineralogically characterized fragments and three micro-drilled inclusions) from the CV carbonaceous chondrite, Allende yield a well-defined 26Al- 26Mg fossil isochron with an ( 26Al/ 27Al) 0 of (5.23 ± 0.13) × 10 - 5 . Internal mineral isochrons obtained for three of these CAIs ( A44A, AJEF, and A43) are consistent with the whole-rock CAI isochron. The mineral isochron of AJEF with ( 26Al/ 27Al) 0 = (4.96 ± 0.25) × 10 - 5 , anchored to our precisely determined absolute 207Pb- 206Pb age of 4567.60 ± 0.36 Ma for the same mineral separates, reinstate the "canonical" ( 26Al/ 27Al) 0 of 5 × 10 - 5 for the early Solar System. The uncertainty in ( 26Al/ 27Al) 0 corresponds to a maximum time span of ± 20 Ka (thousand years), suggesting that the Allende CAI formation events were culminated within this time span. Although all Allende CAIs studied experienced multistage formation history, including melting and evaporation in the solar nebula and post-crystallization alteration likely on the asteroidal parent body, the 26Al- 26Mg and U-Pb-isotopic systematics of the mineral separates and bulk CAIs behaved largely as closed-system since their formation. Our data do not support the "supra-canonical" 26Al/ 27Al ratio of individual minerals or their mixtures in CV CAIs, suggesting that the supra-canonical 26Al/ 27Al ratio in the CV CAIs may have resulted from post

Effects of Al(III) and Nano-Al13 Species on Malate Dehydrogenase Activity

PubMed Central

Yang, Xiaodi; Cai, Ling; Peng, Yu; Li, Huihui; Chen, Rong Fu; Shen, Ren Fang

2011-01-01

The effects of different aluminum species on malate dehydrogenase (MDH) activity were investigated by monitoring amperometric i-t curves for the oxidation of NADH at low overpotential using a functionalized multi-wall nanotube (MWNT) modified glass carbon electrode (GCE). The results showed that Al(III) and Al13 can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III) and Al13 concentration increase. Our study also found that the effects of Al(III) and Al13 on the activity of MDH depended on the pH value and aluminum speciation. Electrochemical and circular dichroism spectra methods were applied to study the effects of nano-sized aluminum compounds on biomolecules. PMID:22163924

Effects of Al(III) and nano-Al13 species on malate dehydrogenase activity.

PubMed

Yang, Xiaodi; Cai, Ling; Peng, Yu; Li, Huihui; Chen, Rong Fu; Shen, Ren Fang

2011-01-01

The effects of different aluminum species on malate dehydrogenase (MDH) activity were investigated by monitoring amperometric i-t curves for the oxidation of NADH at low overpotential using a functionalized multi-wall nanotube (MWNT) modified glass carbon electrode (GCE). The results showed that Al(III) and Al(13) can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III) and Al(13) concentration increase. Our study also found that the effects of Al(III) and Al(13) on the activity of MDH depended on the pH value and aluminum speciation. Electrochemical and circular dichroism spectra methods were applied to study the effects of nano-sized aluminum compounds on biomolecules.

Fracture toughness of Ti-Al3Ti-Al-Al3Ti laminate composites under static and cyclic loading conditions

NASA Astrophysics Data System (ADS)

Patselov, A. M.; Gladkovskii, S. V.; Lavrikov, R. D.; Kamantsev, I. S.

2015-10-01

The static and cyclic fracture toughnesses of a Ti-Al3Ti-Al-Al3Ti laminate composite material containing at most 15 vol % intermetallic compound are studied. Composite specimens are prepared by terminating reaction sintering of titanium and aluminum foils under pressure. The fracture of the titanium layers is quasi-cleavage during cyclic crack growth and is ductile during subsequent static loading.

Co-existence of a few and sub micron inhomogeneities in Al-rich AlGaN/AlN quantum wells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iwata, Yoshiya; Oto, Takao; Banal, Ryan G.

2015-03-21

Inhomogeneity in Al-rich AlGaN/AlN quantum wells is directly observed using our custom-built confocal microscopy photoluminescence (μ-PL) apparatus with a reflective system. The μ-PL system can reach the AlN bandgap in the deep ultra-violet spectral range with a spatial resolution of 1.8 μm. In addition, cathodoluminescence (CL) measurements with a higher spatial resolution of about 100 nm are performed. A comparison of the μ-PL and CL measurements reveals that inhomogeneities, which have different spatial distributions of a few- and sub-micron scales that are superimposed, play key roles in determining the optical properties.

Aluminium (Al) speciation in serum and urine after subcutaneous venom immunotherapy with Al as adjuvant.

PubMed

Michalke, Bernhard; Kramer, Matthias F; Brehler, Randolf

2018-02-21

Aluminium is associated with disorders and is the commonly used vaccine adjuvant. Understanding the mechanisms of how Al is transported, metabolized or of its toxicity depends on the knowledge of Al-interactions with bioligands, i.e. Al-species. Al-speciation in serum is difficult because of low concentration and the risk of exogenous Al contamination. Furthermore, Al-measurements may be hampered according to various interferences. This study aims for developing quality controlled protocols for reliable Al- and Al-species determination and for investigating probable differences in Al (-speciation) after Al-containing subcutaneous immunotherapy (SIT). Sample donors were recruited either for the control group ("class-0", they never had been treated with SIT containing an Al-depot extract) or for the SIT-group ("class-1", they previously had been treated with SIT for insect venom allergy with an Al-depot extract). Blood was drawn for medical reasons and serum prepared. Additionally, some sample donors collected 24-h-urine. They had been informed (and they consented) about the scientific use of their samples. The study was approved by the ethic committee of the "Medical Association Westphalia-Lippe" and of the University of Münster, evaluating the study positively (No. 2013-667-f-S). We applied quality controlled sample preparation and interference-free Al detection by ICP sectorfield-mass spectrometry. Al-species were analysed using size-exclusion-chromatography-ICP-qMS. Al-concentrations or speciation in urine samples showed no differences between class-0 and class-1. Al-citrate was the main uric Al-species. In serum elevated Al-concentrations were found for both classes, with class-1 samples being significantly higher than class-0 (p = 0.041), but class-0 samples being approximately 10-fold too high compared to reference values from non-exposed persons. We identified gel-monovettes as contamination source. In contamination-free samples from HNO 3 -prewashed gel

Synthesis of core-shell AlOOH hollow nanospheres by reacting Al nanoparticles with water

NASA Astrophysics Data System (ADS)

Lozhkomoev, A. S.; Glazkova, E. A.; Bakina, O. V.; Lerner, M. I.; Gotman, I.; Gutmanas, E. Y.; Kazantsev, S. O.; Psakhie, S. G.

2016-05-01

A novel route for the synthesis of boehmite nanospheres with a hollow core and the shell composed of highly crumpled AlOOH nanosheets by oxidizing Al nanopowder in pure water under mild processing conditions is described. The stepwise events of Al transformation into boehmite are followed by monitoring the pH in the reaction medium. A mechanism of formation of hollow AlOOH nanospheres with a well-defined shape and crystallinity is proposed which includes the hydration of the Al oxide passivation layer, local corrosion of metallic Al accompanied by hydrogen evolution, the rupture of the protective layer, the dissolution of Al from the particle interior and the deposition of AlOOH nanosheets on the outer surface. In contrast to previously reported methods of boehmite nanoparticle synthesis, the proposed method is simple, and environmentally friendly and allows the generation of hydrogen gas as a by-product. Due to their high surface area and high, slit-shaped nanoporosity, the synthesized AlOOH nanostructures hold promise for the development of more effective catalysts, adsorbents, vaccines and drug carriers.

Millimeter distance effects of surface plasmon polaritons in electroformed Al-Al2O3-Ag diodes

NASA Astrophysics Data System (ADS)

Hickmott, T. W.

2017-02-01

Electroforming of metal-insulator-metal diodes is a soft dielectric breakdown that changes the high resistance of as-prepared diodes to a low resistance state. Electroforming of Al-Al2O3-metal diodes with anodic Al2O3 results in voltage-controlled negative resistance in the current-voltage (I-V) characteristics, electroluminescence (EL), and electron emission into vacuum (EM). EL is due to electrons injected at the Al-Al2O3 interface combining with radiative defects in Al2O3. Surface plasmon polaritons (SPPs) are electromagnetic waves that can be excited by photons or electrons. SPPs are confined to a metal-dielectric interface, cause large electric fields in the metal and dielectric, and have ranges of micrometers. The temperature dependence of I-V curves, EL, and EM of a group of electroformed Al-Al2O3-Ag diodes with Al2O3 thicknesses between 12 nm and 20 nm, group A, was measured between 200 K and 300 K. After a sequence of temperature measurements, the Al-Al2O3-Ag diodes, the Al-Al2O3 regions between diodes, and portions of the Ag on the glass region that provides contacts to the diodes are darkened. The range of darkening is >7 mm in a diode with 12 nm of Al2O3 and 2.0-3.5 mm in diodes with Al2O3 thicknesses between 14 nm and 20 nm. Darkening is attributed to the occurrence of SPPs generated by EL photons at the Ag-Al2O3 and Al-Al2O3 interfaces. The results are compared to a second group of Al-Al2O3-Ag diodes with identical Al2O3 thicknesses, group B, that were prepared in the same way as the diodes of group A except for a difference in the deposition of Al films for the two groups. Al-Al2O3-Ag diodes of group B exhibit enhanced EL, which is attributed to spontaneous emission of recombination centers in Al2O3 being enhanced by large electromagnetic fields that are due to SPPs that are generated by EL photons.

Electronic transport through Al/InN nanowire/Al junctions

DOE PAGES

Lu, Tzu -Ming; Wang, George T.; Pan, Wei; ...

2016-02-10

We report non-linear electronic transport measurement of Al/Si-doped n-type InN nanowire/Al junctions performed at T = 0.3 K, below the superconducting transition temperature of the Al electrodes. The proximity effect is observed in these devices through a strong dip in resistance at zero bias. In addition to the resistance dip at zero bias, several resistance peaks can be identified at bias voltages above the superconducting gap of the electrodes, while no resistance dip is observed at the superconducting gap. The resistance peaks disappear as the Al electrodes turn normal beyond the critical magnetic field except one which remains visible atmore » fields several times higher than critical magnetic field. An unexpected non-monotonic magnetic field dependence of the peak position is observed. As a result, we discuss the physical origin of these observations and propose that the resistance peaks could be the McMillan-Rowell oscillations arising from different closed paths localized near different regions of the junctions.« less

Rechargeable Al/Cl2 battery with molten AlCl4/-/ electrolyte.

NASA Technical Reports Server (NTRS)

Holleck, G. L.; Giner, J.; Burrows, B.

1972-01-01

A molten salt system based on Al- and Cl2 carbon electrodes, with an AlCl3 alkali chloride eutectic as electrolyte, offers promise as a rechargeable, high energy density battery which can operate at a relatively low temperature. Electrode kinetic studies showed that the electrode reactions at the Al anode were rapid and that the observed passivation phenomena were due to the formation at the electrode surface of a solid salt layer resulting from concentration changes on anodic or cathodic current flow. It was established that carbon electrodes were intrinsically active for chlorine reduction in AlCl3-alkali chloride melts. By means of a rotating vitreous carbon disk electrode, the kinetic parameters were determined.

Two-Phase Eutectic Growth in Al-Cu and Al-Cu-Ag

NASA Astrophysics Data System (ADS)

Senninger, Oriane; Peters, Matthew; Voorhees, Peter W.

2018-02-01

The microstructure developed by two-phase lamellar eutectics (α ) -(θ {-Al}2{Cu}) in Al-Cu and Al-Cu-Ag alloys is analyzed. A model of two-phase eutectic growth in multicomponent alloys is used to determine the scaling law of the eutectic microstructure using the alloy thermophysical properties. The application of the model to these alloys shows that the addition of Ag to Al-Cu alloys does not significantly change the length scale of the microstructure, which is in agreement with previous experimental studies. This is explained by the combined phenomena of the decrease in interface energies with the addition of Ag and the superheating of the (α ) phase interface induced by the Ag composition profile.

Hot Corrosion Behavior of Stainless Steel with Al-Si/Al-Si-Cr Coating

NASA Astrophysics Data System (ADS)

Fu, Guangyan; Wu, Yongzhao; Liu, Qun; Li, Rongguang; Su, Yong

2017-03-01

The 1Cr18Ni9Ti stainless steel with Al-Si/Al-Si-Cr coatings is prepared by slurry process and vacuum diffusion, and the hot corrosion behavior of the stainless steel with/without the coatings is studied under the condition of Na2SO4 film at 950 °C in air. Results show that the corrosion kinetics of stainless steel, the stainless steel with Al-Si coating and the stainless steel with Al-Si-Cr coating follow parabolic laws in several segments. After 24 h corrosion, the sequence of the mass gain for the three alloys is the stainless steel with Al-Si-Cr coating < the stainless steel with Al-Si coating < the stainless steel without any coating. The corrosion products of the three alloys are layered. Thereinto, the corrosion products of stainless steel without coating are divided into two layers, where the outside layer contains a composite of Fe2O3 and FeO, and the inner layer is Cr2O3. The corrosion products of the stainless steel with Al-Si coating are also divided into two layers, of which the outside layer mainly consists of Cr2O3, and the inner layer is mainly SiO2. The corrosion film of the stainless steel with Al-Si-Cr coating is thin and dense, which combines well with substrate. Thereinto, the outside layer is mainly Cr2O3, and the inside layer is Al2O3. In the matrix of all of the three alloys, there exist small amount of sulfides. Continuous and protective films of Cr2O3, SiO2 and Al2O3 form on the surface of the stainless steel with Al-Si and Al-Si-Cr coatings, which prevent further oxidation or sulfide corrosion of matrix metals, and this is the main reason for the much smaller mass gain of the two alloys than that of the stainless steel without any coatings in the 24 h hot corrosion process.

Heterogeneity Index for the Assessment of Relationship Between Land Use Pattern and Road Traffic Congestion in Apapa-Oworoshoki Express way, Lagos Metropolis

NASA Astrophysics Data System (ADS)

Alaigba, D. B.; Soumah, M.; Banjo, M. O.

2017-05-01

The problem of urban mobility is complicated by traffic delay, resulting from poor planning, high population density and poor condition of roads within urban spaces. This study assessed traffic congestion resulting from differential contribution made by various land-uses along Apapa-Oworoshoki expressway in Lagos metropolis. The data for this study was from both primary and secondary sources; GPS point data was collected at selected points for traffic volume count; observation of the nature of vehicular traffic congestion, and land use types along the corridor. Existing data on traffic count along the corridor, connectivity map and land use map sourced from relevant authorities were acquired. Traffic congestion within the area was estimated using volume capacity ratio (V/C). Heterogeneity Index was developed and used to quantify the percentage contribution to traffic volume from various land-use categories. Analytical Hierarchical Processing (AHP) and knowledge-based weighting were used to rank the importance of different heterogeneity indices. Results showed significant relationship between the degree of heterogeneity of the land use pattern and road traffic congestion. Volume Capacity Ratio computed revealed that the route corridor exceeds its designed capacity in the southward direction between the hours of 8am and 12pm on working days. Five major nodes were analyzed along the corridor, and were all above the expected Passenger Car Unit (PCU), these are "Oshodi" 15 %, "Airport junction" 10 %, "Cele bus stop" 21 %, "Mile 2" 14 %, "Berger" 15 % and "Tincan bus stop" 33 % indicating heavy traffic congestion.

Microstructural and Phase Composition Differences Across the Interfaces in Al/Ti/Al Explosively Welded Clads

NASA Astrophysics Data System (ADS)

Fronczek, Dagmara Malgorzata; Chulist, Robert; Litynska-Dobrzynska, Lidia; Lopez, Gabriel Alejandro; Wierzbicka-Miernik, Anna; Schell, Norbert; Szulc, Zygmunt; Wojewoda-Budka, Joanna

2017-09-01

The microstructure and phase composition of Al/Ti/Al interfaces with respect to their localization were investigated. An aluminum-flyer plate exhibited finer grains located close to the upper interface than those present within the aluminum-base plate. The same tendency, but with a higher number of twins, was observed for titanium. Good quality bonding with a wavy shape and four intermetallic phases, namely, TiAl3, TiAl, TiAl2, and Ti3Al, was only obtained at the interface closer to the explosive material. The other interface was planar with three intermetallic compounds, excluding the metastable TiAl2 phase. As a result of a 100-hour annealing at 903 K (630 °C), an Al/TiAl3/Ti/TiAl3/Al sandwich was manufactured, formed with single crystalline Al layers. A substantial difference between the intermetallic layer thicknesses was measured, with 235.3 and 167.4 µm obtained for the layers corresponding to the upper and lower interfaces, respectively. An examination by transmission electron microscopy of a thin foil taken from the interface area after a 1-hour annealing at 825 K (552 °C) showed a mixture of randomly located TiAl3 grains within the aluminum. Finally, the hardness results were correlated with the microstructural changes across the samples.

Projeto do sistema anti-ressonante da fiação dos transdutores para o detector Mario Schenberg

NASA Astrophysics Data System (ADS)

Vieira, S. J.., Jr.; Melo, J. L.

2003-08-01

O detector de ondas gravitacionais Mario Schenberg está sendo projetado e construído pelo grupo Gráviton. Sua construção está ocorrendo no Laboratório de Estado Sólido e Baixas Temperaturas (LESBT) da Universidade de São Paulo, na cidade de São Paulo. Esse detector possui uma massa ressonante esférica de cobre-alumínio, com 65 cm de diâmetro, pesando aproximadamente 1150 Kg, suspensa por um sistema de isolamento vibracional, que se encontra em fase de testes preliminares. A real eficácia desse sistema, entretanto, só poderá ser comprovada quando o detector estiver aparelhado com, pelo menos, um transdutor eletromecânico de altíssima sensibilidade acoplado à massa ressonante. Neste momento, não só este sistema de isolamento vibracional será posto em teste, como o do projeto da fiação que transporta os sinais de microondas até os transdutores e destes para a pré-amplificação. Apesar dessa fiação ter sido projetada para não apresentar nenhum contato com a superfície esférica da antena, de maneira a não haver nenhuma transmissão de ruído vibracional do laboratório para esta, deve-se minimizar o ruído microfônico produzido nessa fiação por oscilações mecânicas, uma vez que ela não utiliza nenhum sistema de isolamento vibracional. Com o intuito de resolver este problema, projetamos uma estrutura, formada por pequenos cilindros conectados por barras, a qual não terá nenhuma ressonância mecânica na faixa de freqüências de interesse para detecção (3000 - 3400 Hz). Desta forma, as vibrações nessa faixa não serão amplificadas. O projeto foi feito usando iterativamente, de maneira a otimizar os resultados obtidos, o programa de elementos finitos Msc/Nastran. Através de simulações feitas neste programa, determinamos os parâmetros geométricos ideais a serem utilizados, os quais proporcionam a maior região espectral de interesse livre de ressonâncias.

Response of rice to Al stress and identification of quantitative trait Loci for Al tolerance.

PubMed

Ma, Jian Feng; Shen, Renfang; Zhao, Zhuqing; Wissuwa, Matthias; Takeuchi, Yoshinobu; Ebitani, Takeshi; Yano, Masahiro

2002-06-01

Rice (Oryza sativa L.) shows the highest tolerance to Al toxicity among small-grain cereal crops, however, the mechanisms and genetics responsible for its high Al tolerance are not yet well understood. We investigated the response of rice to Al stress using the japonica variety Koshihikari in comparison to the indica variety Kasalath. Koshihikari showed higher tolerance at various Al concentrations than Kasalath. The Al content in root apexes was less in Koshihikari than in Kasalath, suggesting that exclusion mechanisms rather than internal detoxification are acting in Koshihikari. Al-induced secretion of citrate was observed in both Koshihikari and Kasalath, however, it is unlikely to be the mechanism for Al tolerance because there was no significant difference in the amount of citrate secreted between Koshihikari and Kasalath. Quantitative trait loci (QTLs) for Al tolerance were mapped in a population of 183 backcross inbred lines (BILs) derived from a cross of Koshihikari and Kasalath. Three putative QTLs controlling Al tolerance were detected on chromosomes 1, 2 and 6. Kasalath QTL alleles on chromosome 1 and 2 reduced Al tolerance but increased tolerance on chromosome 6. The three QTLs explained about 27% of the phenotypic variation in Al tolerance. The existence of QTLs for Al tolerance was confirmed in substitution lines for corresponding chromosomal segments.

An epidemiological study of cutaneous leishmaniasis in Al-jabal Al-gharbi, Libya.

PubMed

Abdellatif, Manal Z M; El-Mabrouk, Khamis; Ewis, Ashraf A

2013-02-01

Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that males were more affected than females (P=0.04), and people above 10-years were more affected than younger ones (P=0.0001). A significant percent of CL cases belonged to Al-Kawasem subprovince (P=0.0001). Farm-related activities were the most frequent occupations among CL cases (P=0.04). In addition to farm workers, housewives and students are at risk groups since they are engaged at farm activities. Moreover, those who have occupations that require staying outdoors for a part of night, e.g., policemen, are also at risk. Compared to children, adult CL patients had multiple lesions (P=0.001) that were more prevalent in their upper and lower extremities than the face (P=0.0001). We conclude that CL is a major health problem in Al-jabal Al-gharbi province of Libya. The presence of rodents and sandflies makes it a suitable environment for Leishmania to spread in an endemic epidemiological pattern. Being engaged in farming activities or outdoor occupations increases the risk of infection. Various clinical patterns of CL suggest the presence of more than 1 species of Leishmania at Al-jabal Al-gharbi province. We propose that the 2 species responsible for CL in this area are L. major and L. tropica. Further investigations to identify the leishmanial species responsible for CL at Al-jabal Al-gharbi together with adoption of preventive and control programs are needed.

An Epidemiological Study of Cutaneous Leishmaniasis in Al-Jabal Al-Gharbi, Libya

PubMed Central

Abdellatif, Manal Z. M.; El-Mabrouk, Khamis

2013-01-01

Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that males were more affected than females (P=0.04), and people above 10-years were more affected than younger ones (P=0.0001). A significant percent of CL cases belonged to Al-Kawasem subprovince (P=0.0001). Farm-related activities were the most frequent occupations among CL cases (P=0.04). In addition to farm workers, housewives and students are at risk groups since they are engaged at farm activities. Moreover, those who have occupations that require staying outdoors for a part of night, e.g., policemen, are also at risk. Compared to children, adult CL patients had multiple lesions (P=0.001) that were more prevalent in their upper and lower extremities than the face (P=0.0001). We conclude that CL is a major health problem in Al-jabal Al-gharbi province of Libya. The presence of rodents and sandflies makes it a suitable environment for Leishmania to spread in an endemic epidemiological pattern. Being engaged in farming activities or outdoor occupations increases the risk of infection. Various clinical patterns of CL suggest the presence of more than 1 species of Leishmania at Al-jabal Al-gharbi province. We propose that the 2 species responsible for CL in this area are L. major and L. tropica. Further investigations to identify the leishmanial species responsible for CL at Al-jabal Al-gharbi together with adoption of preventive and control programs are needed. PMID:23467624

Formation of epitaxial Al 2O 3/NiAl(1 1 0) films: aluminium deposition

NASA Astrophysics Data System (ADS)

Lykhach, Y.; Moroz, V.; Yoshitake, M.

2005-02-01

Structure of epitaxial Al 2O 3 layers formed on NiAl(1 1 0) substrates has been studied by means of reflection high-energy electron diffraction (RHEED). The elucidated structure was compared to the model suggested for 0.5 nm-thick Al 2O 3 layers [K. Müller, H. Lindner, D.M. Zehner, G. Ownby, Verh. Dtsch. Phys. Ges. 25 (1990) 1130; R.M. Jaeger, H. Kuhlenbeck, H.J. Freund, Surf. Sci. 259 (1991) 235]. The stepwise growth of Al 2O 3 film, involving deposition and subsequent oxidation of aluminium onto epitaxial 0.5 nm-thick Al 2O 3 layers, has been investigated. Aluminium was deposited at room temperature, whereas its oxidation took place during annealing at 1070 K. The Al 2O 3 thickness was monitored by means of Auger electron spectroscopy (AES). It was found that Al 2O 3 layer follows the structure of 0.5 nm thick Al 2O 3 film, although a tilting of Al 2O 3(1 1 1) surface plane with respect to NiAl(1 1 0) surface appeared after Al deposition.

Amyotrophic lateral sclerosis (ALS)

MedlinePlus

Lou Gehrig disease; ALS; Upper and lower motor neuron disease; Motor neuron disease ... One out of 10 cases of ALS is due to a genetic defect. The cause is unknown in most other cases. In ALS, motor nerve cells (neurons) waste away ...

All About ALS

MedlinePlus

... by storm with videos of people pouring ice water on themselves for the Ice Bucket Challenge. The worldwide phenomenon raised awareness—and millions of research dollars—for a fatal disease called ALS. ALS ...

Oxidation behavior of Al/Cr coating on Ti2AlNb alloy at 900 °C

NASA Astrophysics Data System (ADS)

Yang, Zhengang; Liang, Wenping; Miao, Qiang; Chen, Bowen; Ding, Zheng; Roy, Nipon

2018-04-01

In this paper, the Al/Cr coating was fabricated on the surface of Ti2AlNb alloy via rf magnetron sputtering and double glow treatment to enhance oxidation resistance. The protective coating with an outer layer of Al and inner layer of Cr has great bonding strength due to the in-diffusion of Cr and the inter-diffusion between Al and Cr to form Al-Cr alloyed layer which has great hardness. Acoustic emission curve which was detected via WS-2005 scratch tester indicates the bonding strength between Al/Cr coating and substrate is great. Morphology of Ti2AlNb alloy with Al/Cr coating after scratch test shows that the scratch is smooth without disbanding, and the depth and breadth of scratch are changed uniformly. The mass change was reduced after oxidation test due to the Al/Cr protective coating. Isothermal oxidation test at 900 °C was researched. Results indicate that Al/Cr coating provided oxidation resistance of Ti2AlNb alloy with prolonged air exposure at 900 °C. Al2O3 was detected by XRD patterns and SEM images, and was formed on the surface of Ti2AlNb alloy to protect substrate during oxidation test. A certain content of Cr is beneficial for the formation of Al2O3. Besides, Cr2O3 was produced under Al2O3 by outward diffusion of Cr to protect substrate sequentially, no cracks were discovered on Al/Cr protective coating. The process of Ti outward diffusion into surface was suppressive due to integration of Cr-Ti and Al-Ti intermetallics. A steady, adherent and continuous coated layer of Al/Cr on Ti2AlNb alloy increases oxidation resistance.

Elastocaloric effect in CuAlZn and CuAlMn shape memory alloys under compression

PubMed Central

Qian, Suxin; Wang, Yi; Pillsbury, Thomas E.; Hada, Yoshiharu; Yamaguchi, Yuki; Fujimoto, Kenjiro; Hwang, Yunho; Radermacher, Reinhard; Cui, Jun; Yuki, Yoji; Toyotake, Koutaro; Takeuchi, Ichiro

2016-01-01

This paper reports the elastocaloric effect of two Cu-based shape memory alloys: Cu68Al16Zn16 (CuAlZn) and Cu73Al15Mn12 (CuAlMn), under compression at ambient temperature. The compression tests were conducted at two different rates to approach isothermal and adiabatic conditions. Upon unloading at a strain rate of 0.1 s−1 (adiabatic condition) from 4% strain, the highest adiabatic temperature changes (ΔTad) of 4.0 K for CuAlZn and 3.9 K for CuAlMn were obtained. The maximum stress and hysteresis at each strain were compared. The stress at the maximum recoverable strain of 4.0% for CuAlMn was 120 MPa, which is 70% smaller than that of CuAlZn. A smaller hysteresis for the CuAlMn alloy was also obtained, about 70% less compared with the CuAlZn alloy. The latent heat, determined by differential scanning calorimetry, was 4.3 J g−1 for the CuAlZn alloy and 5.0 J g−1 for the CuAlMn alloy. Potential coefficients of performance (COPmat) for these two alloys were calculated based on their physical properties of measured latent heat and hysteresis, and a COPmat of approximately 13.3 for CuAlMn was obtained. This article is part of the themed issue ‘Taking the temperature of phase transitions in cool materials’. PMID:27402936

Structural and compositional evolution of Al{sub 3}(Zr,Y) precipitates in Al-Zr-Y alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Haiyan, E-mail: gaohaiyan@sjtu.edu.cn

Structural and compositional evolution of Al{sub 3}(Zr,Y) precipitates in aged Al-Zr-Y alloy was investigated through atom probe tomography (APT) and transmission electron microscope (TEM) analysis and first principles calculations. The results show that short-bar-shaped D0{sub 19}-Al{sub 3}Y with some Zr atoms dissolved in precipitated at the very beginning of decomposition and worked as heterogeneous nuclei for L1{sub 2}-Al{sub 3}Zr with spherical morphology after being aged at 400 °C for 2 h. Quasi-static coarsening happened as the aging treatment lasted from 2 h to 200 h. However, distribution of Zr and Y atoms in Al{sub 3}(Zr,Y) is nearly uniform and Al{submore » 3}(Zr,Y) do not have the typical “Al{sub 3}RE core-Al{sub 3}Zr shell” structure which observed in other RE containing Al-Zr-RE alloys with L1{sub 2}-Al{sub 3}RE as nuclei. First principles calculations revealed that binding energy between Y and Zr is strong during the growth of Al{sub 3}(Zr,Y), which led to the co-precipitation of Y and Zr atoms and attribute to the evolution of Al{sub 3}(Zr,Y). - Highlights: •Al{sub 3}Y precipitated firstly and then became nuclei for Al{sub 3}Zr during aging of Al-Zr-Y. •Al{sub 3}(Zr,Y) precipitates do not have the typical “Al{sub 3}Y core-Al{sub 3}Zr shell” structure. •Strong binding between Y and Zr led to the co-precipitation of Y and Zr atoms.« less

Revisiting Deng et al.'s Multiparty Quantum Secret Sharing Protocol

NASA Astrophysics Data System (ADS)

Hwang, Tzonelih; Hwang, Cheng-Chieh; Yang, Chun-Wei; Li, Chuan-Ming

2011-09-01

The multiparty quantum secret sharing protocol [Deng et al. in Chin. Phys. Lett. 23: 1084-1087, 2006] is revisited in this study. It is found that the performance of Deng et al.'s protocol can be much improved by using the techniques of block-transmission and decoy single photons. As a result, the qubit efficiency is improved 2.4 times and only one classical communication, a public discussion, and two quantum communications between each agent and the secret holder are needed rather than n classical communications, n public discussions, and 3n/2 quantum communications required in the original scheme.

FACTORS ASSOCIATED WITH TB/HIV CO-INFECTION AMONG DRUG SENSITIVE TUBERCULOSIS PATIENTS MANAGED IN A SECONDARY HEALTH FACILITY IN LAGOS, NIGERIA

PubMed Central

Adejumo, Olusola A.; Daniel, Olusoji J.; Otesanya, Andrew F.; Adegbola, Adebukola A.; Femi-Adebayo, Temitope; Bowale, Abimbola; Adesola, Sunday; Kuku, Olugbenga O.; Otemuyiwa, Kehinde O.; Oladega, Shafaatu N.; Johnson, Eze O.; Falana, Ayodeji A.; Dawodu, Olusola; Owuna, Henry; Osoba, Ganiyat; Dacosta, Adetokunbo

2017-01-01

Background: This study assessed factors associated with TB/HIV co-infection among TB patients managed in a secondary health facility in Lagos Nigeria. Materials and Methods: A retrospective review of treatment cards of patients seen at a secondary referral hospital between January 1 2014 and December 31 2014 was conducted. Treatment outcomes and factors associated with TB/HIV co-infection were assessed. Results: Of the 334 records of patients reviewed, the proportion of patients with TB/HIV co-infection was 21.6%. The odds of having TB/HIV co-infection was 2.7 times higher among patients above 40 years than patients less than 25 years (AOR 2.7 95% CI 1.1 – 6.5, p =0.030). In addition, the odds of having TB/HIV co-infection was 3.3 higher among extra-pulmonary TB cases (AOR 3.3; 95% CI 1.2 – 9.5; p = 0.026) and 2.1 times higher among retreated patients (AOR 2.1; 95% CI 1.1 – 3.9; p = 0.017) than pulmonary TB and new patients respectively. The chance of having TB/HIV co-infection was 2.7-fold more in patients with poor treatment outcomes than patients with treatment success (AOR 2.7; 95%CI 1.3 – 5.4; p =0.006). Conclusion: TB/HIV co-infection rate was high in the study area. There is need to put measures in place to improve treatment outcomes of TB/HIV co-infected patients. PMID:28670643

Fabrication of Al/Mg/Al Composites via Accumulative Roll Bonding and Their Mechanical Properties

PubMed Central

Nie, Jinfeng; Liu, Mingxing; Wang, Fang; Zhao, Yonghao; Li, Yusheng; Cao, Yang; Zhu, Yuntian

2016-01-01

Al(1060)/Mg(AZ31)/Al(1060) multilayered composite was successfully produced using an accumulative roll bonding (ARB) process for up to four cycles at an elevated temperature (400 °C). The microstructure evolution of the composites and the bonding characteristics at the interfaces between Al and Mg layers with increasing ARB cycles were characterized through optical microscopy, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). It was found that the grains of Al and Mg layers were significantly refined and Al3Mg2 and Al12 Mg17 intermetallic compound layers formed at the Al/Mg bonding interfaces. The strength increased gradually and the ultimate tensile strength (UTS) reached a maximum value of about 240 MPa at the third pass. Furthermore, the strengthening mechanism of the composite was analyzed based on the fracture morphologies. PMID:28774072

Suppression of gate leakage current in in-situ grown AlN/InAlN/AlN/GaN heterostructures based on the control of internal polarization fields

NASA Astrophysics Data System (ADS)

Kotani, Junji; Yamada, Atsushi; Ishiguro, Tetsuro; Yamaguchi, Hideshi; Nakamura, Norikazu

2017-03-01

This paper investigates the gate leakage characteristics of in-situ AlN capped InAlN/AlN/GaN heterostructures grown by metal-organic vapor phase epitaxy. It was revealed that the leakage characteristics of AlN capped InAlN/AlN/GaN heterostructures are strongly dependent on the growth temperature of the AlN cap. For an AlN capped structure with an AlN growth temperature of 740 °C, the leakage current even increased although there exists a large bandgap material on InAlN/AlN/GaN heterostructures. On the other hand, a large reduction of the gate leakage current by 4-5 orders of magnitudes was achieved with a very low AlN growth temperature of 430 °C. X-ray diffraction analysis of the AlN cap grown at 740 °C indicated that the AlN layer is tensile-strained. In contrast to this result, the amorphous structure was confirmed for the AlN cap grown at 430 °C by transmission electron microscopy. Furthermore, theoretical analysis based on one-dimensional band simulation was carried out, and the large increase in two-dimensional electron gas (2DEG) observed in Hall measurements was well reproduced by taking into account the spontaneous and piezo-electric polarization in the AlN layer grown at 740 °C. For the AlN capped structure grown at 430 °C, it is believed that the reduced polarization field in the AlN cap suppressed the penetration of 2DEG into the InAlN barrier layer, resulting in a small impact on 2DEG mobility and density. We believe that an in-situ grown AlN cap with a very low growth temperature of 430 °C is a promising candidate for high-frequency/high-power GaN-based devices with low gate leakage current.

Depolarization currents in Al 2O 3 and MgAl 2O 4 oxides

NASA Astrophysics Data System (ADS)

Carvalhaes, R. P. M.; Rocha, M. S.; de Souza, S. S.; Blak, A. R.

2004-06-01

In the present work, dipole defects in γ-irradiated and thermally treated samples of Al 2O 3 and MgAl 2O 4 oxides are investigated, applying the thermally stimulated depolarisation currents technique (TSDC). The TSDC spectra of MgAl 2O 4 doped with Fe 2+, Fe 3+, Co 2+, Cr 3+ and Mn 2+ show four bands at 130 K, 160 K, 250 K and 320 K, and the spectra of Al 2O 3 doped with Mg 2+, Cr 3+ and Fe 3+ show bands between 230 K and 260 K. It has been observed that the bands at 130 K, 160 K and 250 K in MgAl 2O 4 spinel and that the 230 K and 240 K bands in Al 2O 3 are related to dipole defects. The other bands are possibly related to different types of charge storage mechanisms (space-charge and interfacial polarisation) or deal with distributions in activation energies and/or in relaxation times. A thermal decrease of the TSDC bands for heat treatments above 1000 K has been observed. In MgAl 2O 4 spinel, the 250 K band could be recovered after γ-irradiation and the two dipole peaks in Al 2O 3 were partially recovered. Thermal treatments affect the dipole aggregation processes in both oxides. Optical absorption (AO) results indicate that the presence of bands of water molecules in the infrared region obstructs the appearance of the TSDC bands in both Al 2O 3 and MgAl 2O 4. The 250 K peak in MgAl 2O 4 was correlated to V-type centres and the 250 K peak in Al 2O 3 to a substitutional Mg 2+ ion near a trapped hole localised on an adjacent oxygen ion.

The growth of high-Al-content InAlGaN quaternary alloys by RF-MBE

NASA Astrophysics Data System (ADS)

Wang, B. Z.; Wang, X. L.; Wang, X. Y.; Guo, L. C.; Wang, X. H.; Xiao, H. L.; Liu, H. X.

2007-02-01

High-Al-content InxAlyGa1-x-yN (x = 1-10%, y = 34-45%) quaternary alloys were grown on sapphire by radio-frequency plasma-excited molecular beam epitaxy. Rutherford back-scattering spectrometry, high resolution x-ray diffraction and cathodoluminescence were used to characterize the InAlGaN alloys. The experimental results show that InAlGaN with an appropriate Al/In ratio (near 4.7, which is a lattice-match to the GaN under-layer) has better crystal and optical quality than the InAlGaN alloys whose Al/In ratios are far from 4.7. Some cracks and V-defects occur in high-Al/In-ratio InAlGaN alloys. In the CL image, the cracks and V-defect regions are the emission-enhanced regions.

Tuberculosis infection control measures in health care facilities offering tb services in Ikeja local government area, Lagos, South West, Nigeria.

PubMed

Kuyinu, Y A; Mohammed, A S; Adeyeye, O O; Odugbemi, B A; Goodman, O O; Odusanya, O O

2016-03-15

Tuberculosis infection among health care workers is capable of worsening the existing health human resource problems of low--and middle-income countries. Tuberculosis infection control is often weakly implemented in these parts of the world therefore, understanding the reasons for poor implementation of tuberculosis infection control guidelines are important. This study was aimed at assessing tuberculosis infection control practices and barriers to its implementation in Ikeja, Nigeria. A cross-sectional study in 20 tuberculosis care facilities (16 public and 4 private) in Ikeja, Lagos was conducted. The study included a facility survey to assess the availability of tuberculosis infection control guidelines, the adequacy of facilities to prevent transmission of tuberculosis and observations of practices to assess the implementation of tuberculosis infection control guidelines. Four focus group discussions were carried out to highlight HCWs' perceptions on tuberculosis infection control guidelines and barriers to its implementation. The observational study showed that none of the clinics had a tuberculosis infection control plan. No clinic was consistently screening patients for cough. Twelve facilities (60%) consistently provided masks to patients who were coughing. Ventilation in the waiting areas was assessed to be adequate in 60% of the clinics while four clinics (20%) possessed N-95 respirators. Findings from the focus group discussions showed weak managerial support, poor funding, under-staffing, lack of space and not wanting to be seen as stigmatizing against tuberculosis patients as barriers that hindered the implementation of TB infection control measures. Tuberculosis infection control measures were not adequately implemented in health facilities in Ikeja, Nigeria. A multi-pronged approach is required to address the identified barriers to the implementation of tuberculosis infection control guidelines.

Preparation, deformation, and failure of functional Al-Sn and Al-Sn-Pb nanocrystalline alloys

NASA Astrophysics Data System (ADS)

Noskova, N. I.; Vil'Danova, N. F.; Filippov, Yu. I.; Churbaev, R. V.; Pereturina, I. A.; Korshunov, L. G.; Korznikov, A. V.

2006-12-01

Changes in the structure, hardness, mechanical properties, and friction coefficient of Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb (wt %) alloys subjected to severe plastic deformation by equal-channel angular pressing (with a force of 40 tonne) and by shear at a pressure of 5 GPa have been studied. The transition into the nanocrystalline state was shown to occur at different degrees of plastic deformation. The hardness exhibits nonmonotonic variations, namely, first it increases and subsequently decreases. The friction coefficient of the Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys quenched from the melt was found to be 0.33; the friction coefficients of these alloys in the submicrocrystalline state (after equal-channel angular pressing) equal 0.24, 0.32, and 0.35, respectively. The effect of disintegration into nano-sized powders was found to occur in the Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys after severe plastic deformation to ɛ = 6.4 and subsequent short-time holding.

Temperature dependence of the dielectric response of anodized Al-Al2O3-metal capacitors

NASA Astrophysics Data System (ADS)

Hickmott, T. W.

2003-03-01

The temperature dependence of capacitance, CM, and conductance, GM, of Al-Al2O3-metal capacitors with Cu, Ag, and Au electrodes has been measured between 100 and 340 K at seven frequencies between 10 kHz and 1 MHz. Al2O3 films between 15 and 64 nm thick were formed by anodizing evaporated Al films in borate-glycol or borate-H2O electrolyte. The interface capacitance at the Al2O3-metal interface, CI, which is in series with the capacitance CD due to the Al2O3 dielectric, is determined from plots of 1/CM versus insulator thickness. CI is not fixed for a given metal-insulator interface but depends on the vacuum system used to deposit the metal electrode. CI is nearly temperature independent. When CI is taken into account the dielectric constant of Al2O3 determined from capacitance measurements is ˜8.3 at 295 K. The dielectric constant does not depend on anodizing electrolyte, insulator thickness, metal electrode, deposition conditions for the metal electrode or measurement frequency. By contrast, GM of Al-Al2O3-metal capacitors depends on both the deposition conditions of the metal and on the metal. For Al-Al2O3-Cu capacitors, GM is larger for capacitors with large values of 1/CI that result when Cu is evaporated in an oil-pumped vacuum system. For Al-Al2O3-Ag capacitors, GM does not depend on the Ag deposition conditions.

Maternal and child under-nutrition in rural and urban communities of Lagos state, Nigeria: the relationship and risk factors

PubMed Central

2013-01-01

Background Poor nutritional status of mothers has a direct and indirect consequence on their own health and that of their children. The objective of this study was to determine the relationship between nutritional status of mothers and their children and the risk factors for under-nutrition among mothers and children in rural and urban communities of Lagos State, Nigeria. Methods This was a cross sectional survey conducted using the multistage random sampling technique. A total of 300 mother-child pairs were studied, consisting of 150 each from rural and urban communities. Under-nutrition in mothers and children was determined using standard criteria. Results The prevalence of under-nutrition among mothers was significantly higher in rural than urban communities (10.7% vs. 2.7%, p = 0.014). The prevalences of underweight and stunted children were also significantly higher in rural than urban communities (19.4% vs. 9.3%, p < 0.001) and (43.3% vs. 12.6%, p < 0.001) respectively. In rural communities, the risk of stunted mothers having children with stunting was about 7 times higher than those who were not (OR 6.7, 95% CI = 1.4-32.0, p = 0.007). In urban communities, undernourished mothers have about 11 and 12 times risk of having children with underweight and wasting respectively (OR 11.2, 95% CI = 1.4-86.5, p = 0.005) and (OR 12.3, 95% CI = 1.6-95.7, p = 0.003) respectively. The identified risk factors for maternal and child under nutrition differs across rural and urban communities. Conclusions The prevalence of maternal and child under-nutrition is high in both communities although higher in rural communities. Efforts at reducing the vicious cycle of under-nutrition among mothers and children should concentrate on addressing risk factors specific for each community. PMID:23880121

Maternal and child under-nutrition in rural and urban communities of Lagos state, Nigeria: the relationship and risk factors.

PubMed

Senbanjo, Idowu O; Olayiwola, Ibiyemi O; Afolabi, Wasiu A; Senbanjo, Olayinka C

2013-07-23

Poor nutritional status of mothers has a direct and indirect consequence on their own health and that of their children. The objective of this study was to determine the relationship between nutritional status of mothers and their children and the risk factors for under-nutrition among mothers and children in rural and urban communities of Lagos State, Nigeria. This was a cross sectional survey conducted using the multistage random sampling technique. A total of 300 mother-child pairs were studied, consisting of 150 each from rural and urban communities. Under-nutrition in mothers and children was determined using standard criteria. The prevalence of under-nutrition among mothers was significantly higher in rural than urban communities (10.7% vs. 2.7%, p = 0.014). The prevalences of underweight and stunted children were also significantly higher in rural than urban communities (19.4% vs. 9.3%, p < 0.001) and (43.3% vs. 12.6%, p < 0.001) respectively. In rural communities, the risk of stunted mothers having children with stunting was about 7 times higher than those who were not (OR 6.7, 95% CI = 1.4-32.0, p = 0.007). In urban communities, undernourished mothers have about 11 and 12 times risk of having children with underweight and wasting respectively (OR 11.2, 95% CI = 1.4-86.5, p = 0.005) and (OR 12.3, 95% CI = 1.6-95.7, p = 0.003) respectively. The identified risk factors for maternal and child under nutrition differs across rural and urban communities. The prevalence of maternal and child under-nutrition is high in both communities although higher in rural communities. Efforts at reducing the vicious cycle of under-nutrition among mothers and children should concentrate on addressing risk factors specific for each community.

Glacier Grey in front of The Cuernos del Paine mountains, photographed from Lago Grey (Grey Lake) during NASA's AirSAR 2004 campaign in Chile

NASA Image and Video Library

2004-03-11

Glacier Grey in front of the Cuernos del Paine mountains, photographed from Lago Grey (Grey Lake) during NASA's AirSAR 2004 campaign in Chile. AirSAR 2004 is a three-week expedition in Central and South America by an international team of scientists that is using an all-weather imaging tool, called the Airborne Synthetic Aperture Radar (AirSAR), located onboard NASA's DC-8 airborne laboratory. Scientists from many parts of the world are combining ground research with NASA's AirSAR technology to improve and expand on the quality of research they are able to conduct. Founded in 1959, Torres del Paine National Park encompasses 450,000 acres in the Patagonia region of Chile. This region is being studied by NASA using a DC-8 equipped with an Airborne Synthetic Aperture Radar (AirSAR) developed by scientists from NASA’s Jet Propulsion Laboratory. This is a very sensitive region that is important to scientists because the temperature has been consistently rising causing a subsequent melting of the region’s glaciers. AirSAR will provide a baseline model and unprecedented mapping of the region. This data will make it possible to determine whether the warming trend is slowing, continuing or accelerating. AirSAR will also provide reliable information on ice shelf thickness to measure the contribution of the glaciers to sea level.

From Snow to Hill to ALS: An epidemiological odyssey in search of ALS causation.

PubMed

Armon, Carmel

2018-05-21

Establishing mechanisms of disease causation in neurodegenerative diseases has long seemed to be beyond the pale of traditional epidemiological tools. Establishing a plausible mechanism for initiation of amyotrophic lateral sclerosis (ALS) has appeared a particularly elusive goal. This review shows that a likely mechanism for ALS initiation may be inferred by applying classical methods of epidemiological inference. Advances in characterizing the biology of ALS suggest that most cases of ALS are cortically-generated, part of the ALS-FTD spectrum, with focal onset and spread by contiguity within the motor super-network. Evidence-based methods identified the most credible exogenous risk factor - smoking. AB Hill's nine viewpoints to inferring causation from association were invoked. The most likely mechanism consistent with smoking being a risk factor for ALS was inferred: cumulative DNA damage, akin to cumulative somatic mutations in carcinogenesis. Focal onset supports the concept that these changes, occurring in a single cell, may trigger the cascade leading to clinical ALS. The plausibility of this mechanism was affirmed by its coherence/consistency with other observations in sporadic, familial and western Pacific ALS. Application of traditional epidemiological reasoning suggests that cumulative DNA damage may contribute to disease onset in ALS. Copyright © 2018 Elsevier B.V. All rights reserved.

Polarization and Fowler-Nordheim tunneling in anodized Al-Al2O3-Au diodes

NASA Astrophysics Data System (ADS)

Hickmott, T. W.

2000-06-01

Polarization in anodic Al2O3 films is measured by using quasi-dc current-voltage (I-V) curves of Al-Al2O3-Au diodes. A reproducible polarization state is established by applying a negative voltage to the Au electrode of a rectifying Al-Al2O3-Au diode. The difference between subsequent I-V curves with Au positive is a measure of polarization in the sample. The magnitude of polarization charge in Al2O3 depends on the anodizing electrolyte. Al2O3 films formed in H2O-based electrolytes have approximately ten times the polarization charge of Al2O3 films formed in ethylene glycol-based electrolyte. Anodizing conditions that produce greater polarizing charge in anodic Al2O3 result in voltage-time curves during anodization under galvanostatic conditions that are nonlinear. Anodic films with greater polarizing charge also have a greater apparent interface capacitance which is independent of Al2O3 thickness. I-V curves of Al-Al2O3-Au diodes for increasing voltage are dominated by polarization. I-V curves for decreasing voltage are reproducible and parallel but depend on the maximum current and voltage reached during the measurement. There is no single current corresponding to a given voltage. I-V curves for decreasing voltage are analyzed assuming that the conduction mechanism is Fowler-Nordheim (FN) tunneling. There is a qualitative difference between the FN tunneling parameters for Al2O3 films formed in H2O-based electrolytes and those formed in ethylene glycol-based electrolyte. For the former the value of the exponential term in the FN analysis increases as the value of maximum voltage and current in an I-V characteristic increases, while the value of the pre-exponential term is nearly constant. For the latter, the exponential term is nearly constant as maximum voltage and current increase, but the pre-exponential term decreases by about 5 decades. Thus polarization charge incorporated during formation of anodized Al2O3 strongly affects the formation of the insulating

From the model of El Sistema in Venezuela to current applications: learning and integration through collective music education.

PubMed

Majno, Maria

2012-04-01

Over the last years, El Sistema--the Venezuelan project started in 1975 and now acknowledged worldwide as the most significant example of collective music education--has inspired a profusion of remarkable initiatives on all continents. From the original impulse by founder José Antonio Abreu, strong social principles of integration are combined with specific musical approaches to achieve individual empowerment as a large-scale alternative to endemic juvenile crime, counteracting the risk factors of social unease, serving as a stimulating example toward emancipation, and providing professional opportunities to the talented. Such a network, in turn, proves to be a powerful instrument of cultural progress: the tenets of "Sistema" become shared values able to foster development, reaching into issues of disability and rehabilitation. This paper presents continuities and contrasts in various ramifications of such a successful trend and outlines perspectives for further impact of this powerful transformational agent. © 2012 New York Academy of Sciences.

CuAlO2 and CuAl2O4 thin films obtained by stacking Cu and Al films using physical vapor deposition

NASA Astrophysics Data System (ADS)

Castillo-Hernández, G.; Mayén-Hernández, S.; Castaño-Tostado, E.; DeMoure-Flores, F.; Campos-González, E.; Martínez-Alonso, C.; Santos-Cruz, J.

2018-06-01

CuAlO2 and CuAl2O4 thin films were synthesized by the deposition of the precursor metals using the physical vapor deposition technique and subsequent annealing. Annealing was carried out for 4-6 h in open and nitrogen atmospheres respectively at temperatures of 900-1000 °C with control of heating and cooling ramps. The band gap measurements ranged from 3.3 to 4.5 eV. Electrical properties were measured using the van der Pauw technique. The preferred orientations of CuAlO2 and CuAl2O4 were found to be along the (1 1 2) and (3 1 1) planes, respectively. The phase percentages were quantified using a Rietveld refinement simulation and the energy dispersive X-ray spectroscopy indicated that the composition is very close to the stoichiometry of CuAlO2 samples and with excess of aluminum and deficiency of copper for CuAl2O4 respectively. High resolution transmission electron microscopy identified the principal planes in CuAlO2 and in CuAl2O4. Higher purities were achieved in nitrogen atmosphere with the control of the cooling ramps.

Three-Dimensional FIB/EBSD Characterization of Irradiated HfAl3-Al Composite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hua, Zilong; Guillen, Donna Post; Harris, William

2016-09-01

A thermal neutron absorbing material, comprised of 28.4 vol% HfAl3 in an Al matrix, was developed to serve as a conductively cooled thermal neutron filter to enable fast flux materials and fuels testing in a pressurized water reactor. In order to observe the microstructural change of the HfAl3-Al composite due to neutron irradiation, an EBSD-FIB characterization approach is developed and presented in this paper. Using the focused ion beam (FIB), the sample was fabricated to 25µm × 25µm × 20 µm and mounted on the grid. A series of operations were carried out repetitively on the sample top surface tomore » prepare it for scanning electron microscopy (SEM). First, a ~100-nm layer was removed by high voltage FIB milling. Then, several cleaning passes were performed on the newly exposed surface using low voltage FIB milling to improve the SEM image quality. Last, the surface was scanned by Electron Backscattering Diffraction (EBSD) to obtain the two-dimensional image. After 50 to 100 two-dimensional images were collected, the images were stacked to reconstruct a three-dimensional model using DREAM.3D software. Two such reconstructed three-dimensional models were obtained from samples of the original and post-irradiation HfAl3-Al composite respectively, from which the most significant microstructural change caused by neutron irradiation apparently is the size reduction of both HfAl3 and Al grains. The possible reason is the thermal expansion and related thermal strain from the thermal neutron absorption. This technique can be applied to three-dimensional microstructure characterization of irradiated materials.« less

The Genyornis Egg: Response to Miller et al.'s commentary on Grellet-Tinner et al., 2016

NASA Astrophysics Data System (ADS)

Grellet-Tinner, Gerald; Spooner, Nigel A.; Handley, Warren D.; Worthy, Trevor H.

2017-04-01

Williams (1981) and Williams and Rich (1991) attributed Australian Quaternary fossil eggshell that differed from that of emu Dromaius novaehollandiae to the extinct bird Genyornis newtoni without any osteological or embryonic support. Such association by proximity or abundance mirrors the case of the mistaken association of oviraptor eggs to Protoceratops in the 1920's by Andrews (Grellet-Tinner and Makovicky, 2006). No other candidate species was considered, and this attribution has been unchallenged and followed by everyone thereafter. Much research has been done on this Australian eggshell, with one result being that the extinction of the parent of this eggshell is the most well documented for a taxon in Australia (e.g., Miller et al., 1999, 2005). Grellet-Tinner et al. (2016) raised several problems with the identity of the eggshell Williams (1981) attributed to Genyornis newtoni and suggested that extinct megapodes of the genus Progura were the more likely layer of this eggshell type, therein referred to as ;putative Genyornis oological material; (PGOM). Miller et al. (2017) challenged our hypothesis stating that ;Based on the dimensions of the reconstructed Spooner Egg,Grellet-Tinner et al. (2016)argue that PGOM is too small for a bird with the body mass estimated for Genyornis (168-275 kg) … …[and] …. None of the additional PGOM observations reported byGrellet-Tinner et al. (2016)are inconsistent with a Genyornis parent;. Here we take the opportunity to respond to their critique, the basis of which resolves into a few points, which we address in turn.

Mowafak Al-Jassim | NREL

Science.gov Websites

Mowafak Al-Jassim Photo of Mowafak Al-Jassim Mowafak Al-Jassim Group Research Manager III-Materials researcher and advancing to a principal scientist and a technical manager. His research group has contributed numerous international conferences. Research Interests His research interests include the multiscale

Data supporting Al-Abed et al., Environ. Sci.: Nano, 2016,

EPA Pesticide Factsheets

Data files representing each of the Figures and Tables published in Al-Abed et al., Environ. Sci.: Nano, 2016,3, 593. The data file names identify the Figure or Table and each file contains an internal set of data definitionsThis dataset is associated with the following publication:Al-Abed, S.R., J. Virkutyte, J. Ortenzio , R.M. McCarrick, L. Degn, R. Zucker , N. Coates , K. Cleveland, H. Ma, S. Diamond, K. Dreher , and W. Boyes. Environmental aging alters AI(OH)3 coating of TiO2 nanoparticles enhancing their photocatalytic and phototoxicity activities. Environmental Science: Nano. RSC Publishing, Cambridge, UK, N/A, (2016).

Two-Phase (TiAl+TiCrAl) Coating Alloys for Titanium Aluminides

NASA Technical Reports Server (NTRS)

Brady, Michael P. (Inventor); Smialek, James L. (Inventor); Brindley, William J. (Inventor)

1998-01-01

A coating for protecting titanium aluminide alloys, including the TiAl gamma + Ti3Al (alpha(sub 2)) class, from oxidative attack and interstitial embrittlement at temperatures up to at least 1000 C. is disclosed. This protective coating consists essentially of titanium, aluminum. and chromium in the following approximate atomic ratio: Ti(41.5-34.5)Al(49-53)Cr(9.5-12.5)

Al Qaeda in the Arabian Peninsula (AQAP): An Al Qaeda Affiliate Case Study

DTIC Science & Technology

2017-10-01

Underwear Bombing ” and an unsuccessful 2010 plan to put parcel bombs on U.S.-bound airplanes. AQAP also seeks to inspire “lone jihad” attacks in the... bomb -maker,5 and Sudanese national Ibrahim al-Qosi, a former bookkeeper for Osama Bin Laden.6 Below the emir are regional commanders and heads of...5 “Profile: Al-Qaeda ‘ Bomb Maker’ Ibrahim al-Asiri,” BBC News, July 4, 2014, http://www.bbc.com/news/world-middle-east-11662143. See also al-Asiri

Screw dislocation-induced growth spirals as emissive exciton localization centers in Al-rich AlGaN/AlN quantum wells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Funato, Mitsuru, E-mail: funato@kuee.kyoto-u.ac.jp; Banal, Ryan G.; Kawakami, Yoichi

2015-11-15

Screw dislocations in Al-rich AlGaN/AlN quantum wells cause growth spirals with an enhanced Ga incorporation, which create potential minima. Although screw dislocations and their surrounding potential minima suggest non-radiative recombination processes within growth spirals, in reality, screw dislocations are not major non-radiative sinks for carriers. Consequently, carriers localized within growth spirals recombine radiatively without being captured by non-radiative recombination centers, resulting in intense emissions from growth spirals.

Transformation to Ni5Al3 in a 63.0 at. pct Ni-Al alloy

NASA Technical Reports Server (NTRS)

Khadkikar, P. S.; Locci, I. E.; Vedula, K.; Michal, G. M.

1993-01-01

Microstructures of 63 at. pct P/M Ni-Al alloys with a composition close to the stoichiometry of the Ni5Al3 phase were investigated using homogenized and quenched specimens aged at low temperatures for various times. Results of analyses of XRD data and electron microscopy observations were used for quantitative phase analysis, performed to calculate the (NiAl + Ni5Al3)/Ni5Al3 phase boundary locations. The measured lattice parameters of Ni5Al3 phase formed at 823, 873, and 923 K indicated an increase in tetragonality of the phase with increasing nickel content.

Formation of Al3Ti/Mg composite by powder metallurgy of Mg-Al-Ti system.

PubMed

Yang, Zi R; Qi Wang, Shu; Cui, Xiang H; Zhao, Yu T; Gao, Ming J; Wei, Min X

2008-07-01

An in situ titanium trialuminide (Al 3 Ti)-particle-reinforced magnesium matrix composite has been successfully fabricated by the powder metallurgy of a Mg-Al-Ti system. The reaction processes and formation mechanism for synthesizing the composite were studied by differential scanning calorimetry (DSC), x-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS). Al 3 Ti particles are found to be synthesized in situ in the Mg alloy matrix. During the reaction sintering of the Mg-Al-Ti system, Al 3 Ti particles are formed through the reaction of liquid Al with as-dissolved Ti around the Ti particles. The formed intermetallic particles accumulate at the original sites of the Ti particles. As sintering time increases, the accumulated intermetallic particles disperse and reach a relatively homogeneous distribution in the matrix. It is found that the reaction process of the Mg-Al-Ti system is almost the same as that of the Al-Ti system. Mg also acts as a catalytic agent and a diluent in the reactions and shifts the reactions of Al and Ti to lower temperatures. An additional amount of Al is required for eliminating residual Ti and solid-solution strengthening of the Mg matrix.

Bulk Al-Al3Zr composite prepared by mechanical alloying and hot extrusion for high-temperature applications

NASA Astrophysics Data System (ADS)

Pourkhorshid, E.; Enayati, M. H.; Sabooni, S.; Karimzadeh, F.; Paydar, M. H.

2017-08-01

Bulk Al/Al3Zr composite was prepared by a combination of mechanical alloying (MA) and hot extrusion processes. Elemental Al and Zr powders were milled for up to 10 h and heat treated at 600°C for 1 h to form stable Al3Zr. The prepared Al3Zr powder was then mixed with the pure Al powder to produce an Al-Al3Zr composite. The composite powder was finally consolidated by hot extrusion at 550°C. The mechanical properties of consolidated samples were evaluated by hardness and tension tests at room and elevated temperatures. The results show that annealing of the 10-h-milled powder at 600°C for 1 h led to the formation of a stable Al3Zr phase. Differential scanning calorimetry (DSC) results confirmed that the formation of Al3Zr began with the nucleation of a metastable phase, which subsequently transformed to the stable tetragonal Al3Zr structure. The tension yield strength of the Al-10wt%Al3Zr composite was determined to be 103 MPa, which is approximately twice that for pure Al (53 MPa). The yield stress of the Al/Al3Zr composite at 300°C is just 10% lower than that at room temperature, which demonstrates the strong potential for the prepared composite to be used in high-temperature structural applications.

On the Solar Stimuli That Initiate Makkah Al Mukaramah, Al-Madinah Al-Munawarah And Jeddah Flash Floods

NASA Astrophysics Data System (ADS)

Elfaki, H.; Yousef, S.; Mawad, Ramy; Algafari, Y. H. O.; Amer, M.; Abdel-Sattar, W.

2017-12-01

Severe solar events manifested as highly energetic X-Ray events accompanied by coronal mass ejections ( CMEs) and proton flares caused flash floods in Makkah Al-Mukaramah, Al-Madinah Al-Munawarah and Jeddah. In the case of the 20 January 2005 CME that initiated severe flash on the 22 of January. it is shown that the CME lowered the pressure in the polar region and extended the low pressure regime to Saudi Arabia passing by the Mediterranean. Such passage accelerated evaporation and caused Cumulonimbus clouds to form and discharge flash floods over Makkah Al-Mukaramah. On the other hand, solar forcing due coronal holes have a different technique in initiating flash floods. The November 25 2009 and the 13-15 January 2011 Jeddah flash floods are attributed to prompt events due to fast solar streams emanated from two coronal holes that arrived the Earth on 24 November 2009 and 13 January 2011. We present evidences that those streams penetrated the Earth's magnetosphere and hit the troposphere at the western part of the Red Sea, dissipated their energy at 925mb geopotential height and left two hot spots. It follows that the air in the hot spots expanded and developed spots of low pressure air that spread over the Red Sea to its eastern coast. Accelerated evaporation due to reduced pressure caused quick formation of Cumulonimbus clouds that caused flash floods over Makkah Al-Mukaramah and Jeddah.

Ultrafast decay of hot phonons in an AlGaN/AlN/AlGaN/GaN camelback channel

NASA Astrophysics Data System (ADS)

Leach, J. H.; Wu, M.; Morkoç, H.; Liberis, J.; Šermukšnis, E.; Ramonas, M.; Matulionis, A.

2011-11-01

A bottleneck for heat dissipation from the channel of a GaN-based heterostructure field-effect transistor is treated in terms of the lifetime of nonequilibrium (hot) longitudinal optical phonons, which are responsible for additional scattering of electrons in the voltage-biased quasi-two-dimensional channel. The hot-phonon lifetime is measured for an Al0.33Ga0.67N/AlN/Al0.1Ga0.9N/GaN heterostructure where the mobile electrons are spread in a composite Al0.1Ga0.9N/GaN channel and form a camelback electron density profile at high electric fields. In accordance with plasmon-assisted hot-phonon decay, the parameter of importance for the lifetime is not the total charge in the channel (the electron sheet density) but rather the electron density profile. This is demonstrated by comparing two structures with equal sheet densities (1 × 1013 cm-2), but with different density profiles. The camelback channel profile exhibits a shorter hot-phonon lifetime of ˜270 fs as compared with ˜500 fs reported for a standard Al0.33Ga0.67N/AlN/GaN channel at low supplied power levels. When supplied power is sufficient to heat the electrons > 600 K, ultrafast decay of hot phonons is observed in the case of the composite channel structure. In this case, the electron density profile spreads to form a camelback profile, and hot-phonon lifetime reduces to ˜50 fs.

Enhancing phosphate adsorption by Mg/Al layered double hydroxide functionalized biochar with different Mg/Al ratios.

PubMed

Li, Ronghua; Wang, Jim J; Zhou, Baoyue; Awasthi, Mukesh Kumar; Ali, Amjad; Zhang, Zengqiang; Gaston, Lewis A; Lahori, Altaf Hussain; Mahar, Amanullah

2016-07-15

Mg/Al ratio plays a significant role for anion adsorption by Mg/Al-layered double hydroxides (Mg/Al-LDHs) modified biochar. In this study, Mg/Al-LDHs biochar with different Mg/Al ratios (2, 3, 4) were prepared by co-precipitation for phosphate removal from aqueous solution. Factors on phosphate adsorption including Mg/Al ratio, pH, and the presence of other inorganic anions were investigated through batch experiments. Increasing Mg/Al ratio in the Mg/Al-LDHs biochar composites generally enhanced phosphate adsorption with Langmuir adsorption maximum calculated at 81.83mg phosphorous (P) per gram of 4:1Mg/Al-LDHs biochar at pH3.0. The adsorption process was best described by the pseudo-second-order kinetic model. Solution pH had greater effects on the phosphate adsorption by Mg/Al LDHs biochar composites with lower Mg/Al ratios. The presence of other inorganic anions decreased the phosphate adsorption efficiency in the order of F(-) > SO4(2-) > NO2(-) >Cl(-). Phosphate adsorption mechanism involves ion exchange, electrostatic attraction and surface inner-sphere complex formation. Overall, Mg/Al-LDHs biochar composites offer a potential alternative of carbon-based adsorbent for phosphate removal from aqueous solution. Copyright © 2016 Elsevier B.V. All rights reserved.

Electronic structures of Al-Si clusters and the magic number structure Al8Si4

NASA Astrophysics Data System (ADS)

Du, Ning; Su, Mingzhi; Chen, Hongshan

2018-02-01

The low-energy structures of Al8Sim (m = 1-6) have been determined by using the genetic algorithm combined with density functional theory and the Second-order Moller-Plesset perturbation theory (MP2) models. The results show that the close-packed structures are preferable in energy for Al-Si clusters and in most cases there exist a few isomers with close energies. The valence molecular orbitals, the orbital level structures and the electron localisation function (ELF) consistently demonstrate that the electronic structures of Al-Si clusters can be described by the jellium model. Al8Si4 corresponds to a magic number structure with pronounced stability and large energy gap; the 40 valence electrons form closed 1S21P61D102S21F142P6 shells. The ELF attractors also suggest weak covalent Si-Si, Si-Al and Al-Al bonding, and doping Si in aluminium clusters promotes the covalent interaction between Al atoms.

Sintering of (Ni,Mg)(Al,Fe)2O4 Materials and their Corrosion Process in Na3AlF6-AlF3-K3AlF6 Electrolyte

NASA Astrophysics Data System (ADS)

Xu, Yibiao; Li, Yawei; Yang, Jianhong; Sang, Shaobai; Wang, Qinghu

2017-06-01

The application of ledge-free sidewalls in the Hall-Héroult cells can potentially reduce the energy requirement of aluminum production by about 30 pct (Nightingale et al. in J Eur Ceram, 33:2761-2765, 2013). However, this approach poses great material challenges since such sidewalls are in direct contact with corrosive electrolyte. In the present paper, (Ni,Mg)(Al,Fe)2O4 materials were prepared using fused magnesia, reactive alumina, nickel oxide, and iron oxide powders as the starting materials. The sintering behaviors of specimens as well as their corrosion resistance to molten electrolyte have been investigated by means of X-ray diffraction and scanning electron microscope. The results show that after firing at temperature ranging from 1673 K (1400 °C) up to 1873 K (1600 °C), all the specimens prepared are composed of single-phase (Ni,Mg)(Al,Fe)2O4 composite spinel, the lattice parameter of which increases with increasing Fe3+ ion concentration. Increasing the iron oxide content enhances densification of the specimens, which is accompanied by the formation of homogeneously distributed smaller pores in the matrix. The corrosion tests show that corrosion layers consist of fluoride and Ni(Al,Fe)2O4 composite spinel grains are produced in specimens with Fe/Al mole ratio no more than 1, whereas dense Ni(Al,Fe)2O4 composite spinel layers are formed on the surface of the specimens with Fe/Al mole ratio more than 1. The dense Ni(Al,Fe)2O4 composite spinel layers formed improve the corrosion resistance of the specimens by inhibiting the infiltration of electrolyte and hindering the chemical reaction between the specimen and electrolyte.

Relationship between Al content and substitution mechanism of Al-bearing anhydrous bridgmanites

NASA Astrophysics Data System (ADS)

Noda, M.; Inoue, T.; Kakizawa, S.

2017-12-01

It is considered that two substitution mechanisms, Tschermak substitution and oxygen vacancy substitution, exist in MgSiO3 bridgmanite for the incorporation of Al in anhydrous condition. Kubo and Akaogi (2000) has conducted the phase equilibrium experiment in the system MgSiO3-Al2O3, and established the phase diagram up to 28 GPa. However the careful observation in the bridgmanite shows that the chemical compositions are slightly deviated from Tschermak substitution join. The same tendency can be also observed in the run products by Irifune et al. (1996). This result indicates that pure Tschermak substitution bridgmanite cannot be stable even in the MgSiO3-Al2O3 join experiment. However, the previous studies used powder samples as the starting materials, so the absorbed water may affect the results. Therefore, we tried to conduct the experiment in the join MgSiO3-Al2O3 in extremely anhydrous condition to clarify whether the pure Tschermak substitution bridgmanite can be stable or not. In addition, we also examined the stability of oxygen vacancy bridgmanite in the extremely anhydrous condition for the comparison. The high pressure synthesis experiments were conducted at 28 GPa and 1600-1700° for 1hour using a Kawai-type multi-anvil apparatus. Four different Al content samples were prepared as the starting materials along the ideal substitution line of Tschermak (Al=0.025, 0.05, 0.1, 0.15 mol) and oxygen-vacancy (Al=0.025, 0.05, 0.075, 0.1 mol) substitutions, respectively (when total cation of 2). The glass rods were used as the starting materials to eliminate the absorbed water on the sample surface. The chemical compositions of the synthesized bridgmanite could not be measured by EPMA because of small grain size less than submicron. Therefore the chemical compositions were estimated from the result of the XRD pattern by subtracting the amount of the other phases. The estimated chemical compositions of Tschermak substitution bridgmanites were consistent with the

Acoustic resonator with Al electrodes on an AlN layer and using a GaAs substrate

DOEpatents

Kline, Gerald R.; Lakin, Kenneth M.

1985-12-03

A method of fabricating an acoustic wave resonator wherein all processing steps are accomplished from a single side of said substrate. The method involves deposition of a multi-layered Al/AlN structure on a GaAs substrate followed by a series of fabrication steps to define a resonator from said composite. The resulting resonator comprises an AlN layer between two Al layers and another layer of AlN on an exterior of one of said Al layers.

Imaging of Al/Fe ratios in synthetic Al-goethite revealed by nanoscale secondary ion mass spectrometry.

PubMed

Pohl, Lydia; Kölbl, Angelika; Werner, Florian; Mueller, Carsten W; Höschen, Carmen; Häusler, Werner; Kögel-Knabner, Ingrid

2018-04-30

Aluminium (Al)-substituted goethite is ubiquitous in soils and sediments. The extent of Al-substitution affects the physicochemical properties of the mineral and influences its macroscale properties. Bulk analysis only provides total Al/Fe ratios without providing information with respect to the Al-substitution of single minerals. Here, we demonstrate that nanoscale secondary ion mass spectrometry (NanoSIMS) enables the precise determination of Al-content in single minerals, while simultaneously visualising the variation of the Al/Fe ratio. Al-substituted goethite samples were synthesized with increasing Al concentrations of 0.1, 3, and 7 % and analysed by NanoSIMS in combination with established bulk spectroscopic methods (XRD, FTIR, Mössbauer spectroscopy). The high spatial resolution (50-150 nm) of NanoSIMS is accompanied by a high number of single-point measurements. We statistically evaluated the Al/Fe ratios derived from NanoSIMS, while maintaining the spatial information and reassigning it to its original localization. XRD analyses confirmed increasing concentration of incorporated Al within the goethite structure. Mössbauer spectroscopy revealed 11 % of the goethite samples generated at high Al concentrations consisted of hematite. The NanoSIMS data show that the Al/Fe ratios are in agreement with bulk data derived from total digestion and demonstrated small spatial variability between single-point measurements. More advantageously, statistical analysis and reassignment of single-point measurements allowed us to identify distinct spots with significantly higher or lower Al/Fe ratios. NanoSIMS measurements confirmed the capacity to produce images, which indicated the uniform increase in Al-concentrations in goethite. Using a combination of statistical analysis with information from complementary spectroscopic techniques (XRD, FTIR and Mössbauer spectroscopy) we were further able to reveal spots with lower Al/Fe ratios as hematite. Copyright © 2018 John

Burden of rare variants in ALS genes influences survival in familial and sporadic ALS.

PubMed

Pang, Shirley Yin-Yu; Hsu, Jacob Shujui; Teo, Kay-Cheong; Li, Yan; Kung, Michelle H W; Cheah, Kathryn S E; Chan, Danny; Cheung, Kenneth M C; Li, Miaoxin; Sham, Pak-Chung; Ho, Shu-Leong

2017-10-01

Genetic variants are implicated in the development of amyotrophic lateral sclerosis (ALS), but it is unclear whether the burden of rare variants in ALS genes has an effect on survival. We performed whole genome sequencing on 8 familial ALS (FALS) patients with superoxide dismutase 1 (SOD1) mutation and whole exome sequencing on 46 sporadic ALS (SALS) patients living in Hong Kong and found that 67% had at least 1 rare variant in the exons of 40 ALS genes; 22% had 2 or more. Patients with 2 or more rare variants had lower probability of survival than patients with 0 or 1 variant (p = 0.001). After adjusting for other factors, each additional rare variant increased the risk of respiratory failure or death by 60% (p = 0.0098). The presence of the rare variant was associated with the risk of ALS (Odds ratio 1.91, 95% confidence interval 1.03-3.61, p = 0.03), and ALS patients had higher rare variant burden than controls (MB, p = 0.004). Our findings support an oligogenic basis with the burden of rare variants affecting the development and survival of ALS. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Impact of the 26mAl(p, γ) reaction to galactic 26Al yield

NASA Astrophysics Data System (ADS)

Kahl, D.; Shimizu, H.; Yamaguchi, H.; Abe, K.; Beliuskina, O.; Cha, S. M.; Chae, K. Y.; Chen, A. A.; Ge, Z.; Hayakawa, S.; Imai, N.; Iwasa, N.; Kim, A.; Kim, D. H.; Kim, M. J.; Kubono, S.; Kwag, M. S.; Liang, J.; Moon, J. Y.; Nishimura, S.; Oka, S.; Park, S. Y.; Psaltis, A.; Teranishi, T.; Ueno, Y.; Yang, L.

2018-04-01

Astrophysical observables that are directly linked to nuclear physics inputs provide critical and stringent constraints on nucleosynthetic models. As 26Al was the first specific radioactivity observed in the Galaxy, its origin has fascinated the nuclear astrophysics community for nearly forty years. Despite extensive research, the precise origins of 26Al remain elusive. At present, the sum of all putative stellar contributions generally overestimates the 26Al mass in the interstellar medium. Among the many reactions that influence the yield of 26Al, radiative proton capture on its isomer 26mAl is one of the least constrained reactions by experimental data. To this end, we developed a 26Al isomeric beam and performed proton elastic scattering to search for low-spin states in 27Si. The experimental method and the preliminary results of this on-going study will be presented.

Removal of metallic Al and Al/Zn alloys in MSWI bottom ash by alkaline treatment.

PubMed

Xuan, Dongxing; Poon, Chi Sun

2018-02-15

In order to reduce the leaching of pollutants and remove the Al and Zn/Al alloy from municipal solid waste incineration bottom ash (MSWIBA), an optimized alkaline pre-treatment procedure was developed in this study. The influences of alkaline conditions on the removal rate of Al and Zn/Al alloy were investigated, including [OH] - concentration, temperature, particle size, liquid/solid ratio and treatment duration. The experimental results showed that the optimized alkaline pre-treatment conditions to efficiently remove the Al and Zn/Al alloy was by using a minimum of 1.0mol/l [OH] - , at 55°C and with a minimal liquid/solid ratio of 5. The removal rate of Al and Zn/Al alloy followed an S-shape curve, in which the slow beginning stage was attributed to the protection of the oxidation layer and the quenched product around the Al and Al/Zn alloy. After 3h of the optimized alkaline pre-treatment, the leaching of Cr, Cu, Pb and Zn of the treated MSWIBA was reduced by more than 90% of that of the original MSWIBA. The alkali-silica reaction test further indicated that the expansion of concrete prepared with the pre-treated MSWIBA was significantly reduced and there was no macro-crack or spalling damage on the surface of the tested specimens. Copyright © 2017 Elsevier B.V. All rights reserved.

Current transport mechanism in graphene/AlGaN/GaN heterostructures with various Al mole fractions

NASA Astrophysics Data System (ADS)

Pandit, Bhishma; Seo, Tae Hoon; Ryu, Beo Deul; Cho, Jaehee

2016-06-01

The current transport mechanism of graphene formed on AlxGa1-xN/GaN heterostructures with various Al mole fractions (x = 0.15, 0.20, 0.30, and 0.40) is investigated. The current-voltage measurement from graphene to AlGaN/GaN shows an excellent rectifying property. The extracted Schottky barrier height of the graphene/AlGaN/GaN contacts increases with the Al mole fraction in AlGaN. However, the current transport mechanism deviates from the Schottky-Mott theory owing to the deterioration of AlGaN crystal quality at high Al mole fractions confirmed by reverse leakage current measurement.

Comparison of ALS functionality and plant growth in ALS-inhibitor susceptible and resistant Myosoton aquaticum L.

PubMed

Liu, Weitang; Bai, Shuang; Jia, Sisi; Guo, Wenlei; Zhang, Lele; Li, Wei; Wang, Jinxin

2017-10-01

Herbicide target-site resistance mutations may cause pleiotropic effects on plant ecology and physiology. The effect of several known (Pro197Ser, Pro197Leu Pro197Ala, and Pro197Glu) target-site resistance mutations of the ALS gene on both ALS functionality and plant vegetative growth of weed Myosoton aquaticum L. (water chickweed) have been investigated here. The enzyme kinetics of ALS from four purified water chickweed populations that each homozygous for the specific target-site resistance-endowing mutations were characterized and the effect of these mutations on plant growth was assessed via relative growth rate (RGR) analysis. Plants homozygous for Pro197Ser and Pro197Leu exhibited higher extractable ALS activity than susceptible (S) plants, while all ALS mutations with no negative change in ALS kinetics. The Pro197Leu mutation increased ALS sensitivity to isoleucine and valine, and Pro197Glu mutation slightly increased ALS sensitivity to isoleucine. RGR results indicated that none of these ALS resistance mutations impose negative pleiotropic effects on relative growth rate. However, resistant (R) seeds had a lowed germination rate than S seeds. This study provides baseline information on ALS functionality and plant growth characteristics associated with ALS inhibitor resistance-endowing mutations in water chickweed. Copyright © 2017. Published by Elsevier Inc.

Structural inheritance and difference between Ti 2AlC, Ti 3AlC 2  and Ti 5Al 2C 3 under pressure from first principles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Qing -He; Du, An; Yang, Ze -Jin

The structural inheritance and difference between Ti 2AlC, Ti 3AlC 2 and Ti 5Al 2C 3 under pressure from first principles are studied. The results indicate that the lattice parameter a are almost the same within Ti 2AlC, Ti 3AlC 2 and Ti 5Al 2C 3, and the value of c in Ti 5Al 2C 3 is the sum of Ti 2AlC and Ti 3AlC 2 which is revealed by the covalently bonded chain in the electron density difference: Al–Ti–C–Ti–Al for Ti 2AlC, Al–Ti 2–C–Ti 1–C–Ti 2–Al for Ti 3AlC 2 and Al–Ti 3–C 2–Ti 3–Al–Ti 2–C 1–Ti 1–C 1–Timore » 2–Al for Ti 5Al 2C 3. The calculated axial compressibilities, volumetric shrinkage, elastic constant c 11, c 33/c 11 ratio, bulk modulus, shear modulus, and Young’s modulus of Ti 5Al 2C 3 are within the range of the end members (Ti 2AlC and Ti 3AlC 2) in a wide pressure range of 0–100 GPa. Only Ti 2AlC is isotropic crystal at about 50 GPa within the Ti–Al–C compounds. All of the Ti 3 d density of states curves of the three compounds move from lower energy to higher energy level with pressure increasing. The similarities of respective bond length, bond overlap population (Ti–C, Ti–Al and Ti–Ti), atom Mulliken charges under pressure as well as the electron density difference for the three compounds are discovered. Among the Ti–Al–C ternary compounds, Ti–Ti bond behaves least compressibility, whereas the Ti–Al bond is softer than that of Ti–C bonds, which can also been confirmed by the density of states and electron density difference. Bond overlap populations of Ti–Ti, Ti–C and Ti–Al indicate that the ionicity interaction becomes more and more stronger in the three structures as the pressure increasing. Lastly, Mulliken charges of Ti 1, Ti 2, Ti 3, C and Al are 0.65, 0.42, 0.39, –0.73, –0.04 at 0 GPa, respectively, which are consistent with the Pauling scale.« less

Structural inheritance and difference between Ti 2AlC, Ti 3AlC 2  and Ti 5Al 2C 3 under pressure from first principles

DOE PAGES

Gao, Qing -He; Du, An; Yang, Ze -Jin

2017-02-08

The structural inheritance and difference between Ti 2AlC, Ti 3AlC 2 and Ti 5Al 2C 3 under pressure from first principles are studied. The results indicate that the lattice parameter a are almost the same within Ti 2AlC, Ti 3AlC 2 and Ti 5Al 2C 3, and the value of c in Ti 5Al 2C 3 is the sum of Ti 2AlC and Ti 3AlC 2 which is revealed by the covalently bonded chain in the electron density difference: Al–Ti–C–Ti–Al for Ti 2AlC, Al–Ti 2–C–Ti 1–C–Ti 2–Al for Ti 3AlC 2 and Al–Ti 3–C 2–Ti 3–Al–Ti 2–C 1–Ti 1–C 1–Timore » 2–Al for Ti 5Al 2C 3. The calculated axial compressibilities, volumetric shrinkage, elastic constant c 11, c 33/c 11 ratio, bulk modulus, shear modulus, and Young’s modulus of Ti 5Al 2C 3 are within the range of the end members (Ti 2AlC and Ti 3AlC 2) in a wide pressure range of 0–100 GPa. Only Ti 2AlC is isotropic crystal at about 50 GPa within the Ti–Al–C compounds. All of the Ti 3 d density of states curves of the three compounds move from lower energy to higher energy level with pressure increasing. The similarities of respective bond length, bond overlap population (Ti–C, Ti–Al and Ti–Ti), atom Mulliken charges under pressure as well as the electron density difference for the three compounds are discovered. Among the Ti–Al–C ternary compounds, Ti–Ti bond behaves least compressibility, whereas the Ti–Al bond is softer than that of Ti–C bonds, which can also been confirmed by the density of states and electron density difference. Bond overlap populations of Ti–Ti, Ti–C and Ti–Al indicate that the ionicity interaction becomes more and more stronger in the three structures as the pressure increasing. Lastly, Mulliken charges of Ti 1, Ti 2, Ti 3, C and Al are 0.65, 0.42, 0.39, –0.73, –0.04 at 0 GPa, respectively, which are consistent with the Pauling scale.« less

A study on wear resistance and microcrack of the Ti 3Al/TiAl + TiC ceramic layer deposited by laser cladding on Ti-6Al-4V alloy

NASA Astrophysics Data System (ADS)

Li, Jianing; Chen, Chuanzhong; Squartini, Tiziano; He, Qingshan

2010-12-01

Laser cladding of the Al + TiC alloy powder on Ti-6Al-4V alloy can form the Ti 3Al/TiAl + TiC ceramic layer. In this study, TiC particle-dispersed Ti 3Al/TiAl matrix ceramic layer on the Ti-6Al-4V alloy by laser cladding has been researched by means of X-ray diffraction, scanning electron microscope, electron probe micro-analyzer, energy dispersive spectrometer. The main difference from the earlier reports is that Ti 3Al/TiAl has been chosen as the matrix of the composite coating. The wear resistance of the Al + 30 wt.% TiC and the Al + 40 wt.% TiC cladding layer was approximately 2 times greater than that of the Ti-6Al-4V substrate due to the reinforcement of the Ti 3Al/TiAl + TiC hard phases. However, when the TiC mass percent was above 40 wt.%, the thermal stress value was greater than the materials yield strength limit in the ceramic layer, the microcrack was present and its wear resistance decreased.

Al-Mg isotopic evidence for episodic alteration of Ca-Al-rich inclusions from Allende

NASA Astrophysics Data System (ADS)

Fagan, T. J.; Guan, Y.; MacPherson, G. J.

2007-08-01

Textures, mineral assemblages, and Al-Mg isotope systematics indicate a protracted, episodic secondary mineralization history for Allende Ca-Al-rich inclusions (CAIs). Detailed observations from one type B1 CAI, one B2, one compact type A (CTA), and one fluffy type A (FTA) indicate that these diverse types of CAIs are characterized by two distinct textural and mineralogic types of secondary mineralization: (1) grossular-rich domains, concentrated along melilite grain boundaries in CAI interiors, and (2) feldspathoid-bearing domains, confined mostly to CAI margins just interior to the Wark-Lovering rim sequence. The Al-Mg isotopic compositions of most secondary minerals in the type B1 CAI, and some secondary minerals in the other CAIs, show no resolvable excesses of 26Mg, whereas the primary CAI phases mostly yield correlated excesses of 26Mg with increasing Al/Mg corresponding to "canonical" initial 26Al/27Al ˜ 4.5-5 × 10-5. These secondary minerals formed at least 3 Ma after the primary CAI minerals. All but two analyses of secondary minerals from the fluffy type-A CAI define a correlated increase in 26Mg/24Mg with increasing Al/Mg, yielding (26Al/27Al)0 = (4.9 ± 2.8) × 10-6. The secondary minerals in this CAI formed 1.8-3.2 Ma after the primary CAI minerals. In both cases, the timing of secondary alteration is consistent with, but does not necessarily require, alteration in an asteroidal setting. One grossular from the type B2 CAI, and several grossular and secondary feldspar analyses from the compact type A CAI, have excesses of 26Mg consistent with initial 26Al/27Al ˜ 4.5 × 10-5. Especially in the compact type A CAI, where 26Mg/24Mg in grossular correlates with increasing Al/Mg, these 26Mg excesses are almost certainly due to in situ decay of 26Al. They indicate a nebular setting for formation of the grossular. The preservation of these diverse isotopic patterns indicates that heating on the Allende parent body was not pervasive enough to reset isotopic

Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

PubMed Central

Wang, Xiao; Wang, Wei; Wang, Jingli; Wu, Hao; Liu, Chang

2017-01-01

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgGa δ doped AlGaN SLs. Mg acceptor activation energy was significantly reduced from 0.378 to 0.331 eV by using MgGa δ doping in SLs instead of traditional doping in alloys. This new process was confirmed to be able to realize high p-type doping in high Al-content AlGaN. PMID:28290480

Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

NASA Astrophysics Data System (ADS)

Wang, Xiao; Wang, Wei; Wang, Jingli; Wu, Hao; Liu, Chang

2017-03-01

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgGa δ doped AlGaN SLs. Mg acceptor activation energy was significantly reduced from 0.378 to 0.331 eV by using MgGa δ doping in SLs instead of traditional doping in alloys. This new process was confirmed to be able to realize high p-type doping in high Al-content AlGaN.

Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice.

PubMed

Wang, Xiao; Wang, Wei; Wang, Jingli; Wu, Hao; Liu, Chang

2017-03-14

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN) 5 /(GaN) 1 superlattice (SL) in Al 0.83 Ga 0.17 N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as Mg Ga δ doped AlGaN SLs. Mg acceptor activation energy was significantly reduced from 0.378 to 0.331 eV by using Mg Ga δ doping in SLs instead of traditional doping in alloys. This new process was confirmed to be able to realize high p-type doping in high Al-content AlGaN.

Al-centered icosahedral ordering in Cu46Zr46Al8 bulk metallic glass

NASA Astrophysics Data System (ADS)

Fang, H. Z.; Hui, X.; Chen, G. L.; Liu, Z. K.

2009-03-01

Icosahedral short-range order, of which Al atoms are caged in the center of icosahedra with Cu and Zr atoms being the vertices, has been evidenced in the Cu46Zr46Al8 glassy structure by ab initio molecular dynamics simulation. These Al-centered clusters distribute irregularly in the three-dimensional space and form a "backbone" structure of the Cu46Zr46Al8 glass alloy. It is suggested that this kind of local structural feature is attributed to the requirement of efficient dense packing and the chemical affinity between Zr-Zr, Zr-Al, and Cu-Zr atoms. Our calculated results are found to be in good agreement with the experimental data.

Al Basrah, Iraq

NASA Image and Video Library

2017-12-08

Al Basrah, Iraq Sensor: L7 ETM+ Acquisition Date: April 4, 2003 Path/Row: 166/39 Lat/Long: 30.486/47.811 Smoke drifts south in this image of Al Basrah, located in southeastern Iraq. The green circles from the center to the left of the image represent irrigated crops.

Al Speciation in Silicate Melts: AlV a new Network Former?

NASA Astrophysics Data System (ADS)

Neuville, D. R.; Florian, P.; de Ligny, D.; Montouillout, V.; Massiot, D.

2009-05-01

The first human glasses were made 3500 BC. It was essentially sodo-lime silicate glass. To improve the chemical resistance, the thermal properties and increase the viscosity it is interesting to add aluminum in these silicates. But what is the speciation of the aluminum and how it varies according to the chemical composition and to the temperature? The aluminum appears essentially in four or five fold coordination in glasses and melts melted. The proportion of [5]Al varies according to the alkaline or to the earth-alkaline content and to the temperature. We shall present in a first part the influence of the network-modifier on the proportion of [5]Al and then we shall present some new results of absorption of high-temperature using NMR and XANES spectroscopy at the Al K-edge. Finally, from glass transition temperature measurements we propose to explain that [5]Al can be a new network former.

Microstructure and Properties of 5083 Al/1060 Al/AZ31 Composite Plate Fabricated by Explosive Welding

NASA Astrophysics Data System (ADS)

Yang, Suyuan; Bao, Jiawei

2018-03-01

A 5083 Al/1060 Al/AZ31 composite plate was fabricated by explosive welding. The microstructure and properties of the composite plate were investigated after explosive welding. The results showed that all bonding interfaces were wavy interfaces. With an increasing distance from the detonation point, the wavelength and the amplitude also increased. The EDS results indicated that a 5-μm diffusion layer was observed at the 1060 Al/AZ31 layer, including the Mg2Al3 phase. Adiabatic shear bands and twin structures were observed in AZ31. The shear bond strength of the 5083 Al/1060 Al interface was 60 MPa, and the shear bond strength of the 1060 Al/AZ31 interface was 84 MPa.

NEK1 genetic variability in a Belgian cohort of ALS and ALS-FTD patients.

PubMed

Nguyen, Hung Phuoc; Van Mossevelde, Sara; Dillen, Lubina; De Bleecker, Jan L; Moisse, Matthieu; Van Damme, Philip; Van Broeckhoven, Christine; van der Zee, Julie

2018-01-01

We evaluated the genetic impact of the amyotrophic lateral sclerosis (ALS) risk gene never in mitosis gene a-related kinase 1 (NEK1) in a Belgian cohort of 278 patients with ALS (n = 245) or ALS with frontotemporal dementia (ALS-FTD, n = 33) and 609 control individuals. We identified 2 ALS patients carrying a loss-of-function (LOF) mutation, p.Leu854Tyrfs*2 and p.Tyr871Valfs*17, that was absent in the control group. A third LOF variant p.Ser1036* was present in 2 sibs with familial ALS but also in an unrelated control person. Missense variants were common in both patients (3.6%) and controls (3.0%). The missense variant, p.Arg261His, which was previously associated with ALS risk, was detected with a minor allele frequency of 0.90% in patients compared to 0.33% in controls. Taken together, NEK1 LOF variants accounted for 1.1% of patients, although interpretation of pathogenicity and penetrance is complicated by the observation of occasional LOF variants in unaffected individuals (0.16%). Furthermore, enrichment of additional ALS gene mutations was observed in NEK1 carriers, suggestive of a "second hit" model were NEK1 variants may modify disease presentation of driving mutations. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Arsenic entrapment by nanocrystals of Al-magnetite: The role of Al in crystal growth and As retention.

PubMed

Freitas, Erico T F; Stroppa, Daniel G; Montoro, Luciano A; de Mello, Jaime W V; Gasparon, Massimo; Ciminelli, Virginia S T

2016-09-01

The nature of As-Al-Fe co-precipitates aged for 120 days are investigated in detail by High Resolution Transmission Electron Microscopy (HRTEM), Scanning TEM (STEM), electron diffraction, Energy Dispersive X-Ray Spectroscopy (EDS), Electron Energy-Loss Spectroscopy (EELS), and Energy Filtered Transmission Electron Microscopy (EFTEM). The Al present in magnetite is shown to favour As incorporation (up to 1.10 wt%) relative to Al-free magnetite and Al-goethite, but As uptake by Al-magnetite decreases with increasing Al substitution (3.53-11.37 mol% Al). Arsenic-bearing magnetite and goethite mesocrystals (MCs) are formed by oriented aggregation (OA) of primary nanoparticles (NPs). Well-crystalline magnetite likely formed by Otswald ripening was predominant in the Al-free system. The As content in Al-goethite MCs (having approximately 13% substituted Al) was close to the EDS detection limit (0.1 wt% As), but was below detection in Al-goethites with 23.00-32.19 mol% Al. Our results show for the first time the capacity of Al-magnetite to incorporate more As than Al-free magnetite, and the role of Al in favouring OA-based crystal growth under the experimental conditions, and therefore As retention in the formed MCs. The proposed mechanism of As incorporation involves adsorption of As onto the newly formed NPs. Arsenic is then trapped in the MCs as they grow by self-assembly OA upon attachment of the NPs. We conclude that Al may diffuse to the crystal faces with high surface energy to reduce the total energy of the system during the attachment events, thus favouring the oriented aggregation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Compliance with driver's license laws and illegal licensing among commercial bus drivers in Lagos, Nigeria: policy implications and evidence for action.

PubMed

Okafor, I P; Odeyemi, K A; Dolapo, D C; Adegbola, A A

2014-09-01

To determine the level of compliance with driver's license laws among commercial bus drivers in Lagos, Nigeria. Two intercity motor parks were selected by simple random sampling and all consenting minibus drivers participated in the study. Key Informant Interviews (KIIs) were also conducted with selected officials in the driver training and licensing authorities. Compliance with the minimum age for driving was high (93.6%), so also was having driving test prior to driver's license procurement (83.3%). Formal driver training and VA testing were very low, (26.1% and 32.9% respectively) Overall, only 9.3% of them were found to have fulfilled all the pre-license obligations before obtaining their first driver's license. The odds of a driver with a secondary education having formal driver training is 3.33 times higher than those with no education (OR 3.33, 95% CI 1.01-11.35). Drivers who were 60 years or older were 3.62 times more likely to be compliant than those who were between 20-29 years (OR 3.62, 95% CI 0.56-29.19). For the 98.3% of them who possessed valid licenses, 52.3% of them obtained them illegally. All the key officials saw RTIs as a serious public health problem but faced several challenges in the course of their work. Overall compliance with pre-license regulations was very poor. There is need for a review and strict enforcement of driver's license laws to improve compliance. Also vital are fostering inter-sectoral collaboration and improvement in the operations of all establishments involved in driver training and license procurement in Nigeria.

Electronic circuits having NiAl and Ni.sub.3 Al substrates

DOEpatents

Deevi, Seetharama C.; Sikka, Vinod K.

1999-01-01

An electronic circuit component having improved mechanical properties and thermal conductivity comprises NiAl and/or Ni.sub.3 Al, upon which an alumina layer is formed prior to applying the conductive elements. Additional layers of copper-aluminum alloy or copper further improve mechanical strength and thermal conductivity.

Lateglacial-Holocene abrupt vegetation changes at Lago Trifoglietti in Calabria, Southern Italy: The setting of ecosystems in a refugial zone

NASA Astrophysics Data System (ADS)

Beaulieu, Jacques-Louis de; Brugiapaglia, Elisabetta; Joannin, Sébastien; Guiter, Frédéric; Zanchetta, Giovanni; Wulf, Sabine; Peyron, Odile; Bernardo, Liliana; Didier, Julien; Stock, Agnès; Rius, Damien; Magny, Michel

2017-02-01

Retrospective science such as palaeoecology deeply depends on the preservation of archives in sensitive places. As an example, mountains of medium altitude from Mediterranean peninsulas have long been identified by biogeographers as refuges zones allowing the survival of European temperate taxa during the ice ages, but archives to validate this hypothesis are scarce, especially in Southern Italy. Here we present a new sequence from Lago Trifoglietti (1048 m a.s.l.) in the Calabrian Mountains, which covers the Late Glacial Interstadial (LGI, corresponding to the Bölling-Alleröd period in northern-central Europe) and the transition to the Holocene. The independent chronology based on seven radiocarbon dates is supported by the evidence of three tephra layers already identified in other regional sequences. During the LGI, besides the high diversity of non arboreal pollen grains, a great number of pollens of temperate forest trees are present or abundant (mostly deciduous oaks and fir). These assemblages suggest that the site was above but not far from the upper limit of diversified woodland stands. They confirm a local survival during the last glacial. The Younger Dryas is not marked by major changes, and oak percentages are even higher, suggesting a resilient expansion at lower altitude. Surprisingly the site remains above the timberline until an aridity crisis centered at 11,100 cal 14C yr PB, which is correlated with the Preboreal Oscillation (PBO). This event is immediately followed by the local settlement of a dense fir and beech forest around the lake. A comparison with other Italian key sequences aims at explaining the climate forcing factors that governed this original vegetation dynamic. Further investigations using additional proxies are needed for a more robust climate reconstruction.

Improving the management of acute diarrhoea and dehydration in under-5 children in a paediatric referral facility in Lagos, Nigeria.

PubMed

Senbanjo, Idowu O; Ch'ng, Chin Lye; Allen, Stephen J

2017-02-01

Mortality from acute diarrhoea and dehydration (AD/D) in children is high despite existing management guidelines. The aim of this study was to identify deficiencies in the management of AD/D by health staff and assess changes in management after a training intervention in a paediatric referral facility in Lagos, Nigeria. In a retrospective review of case notes, the management of AD/D was assessed using WHO guidelines as the standard. An e-learning module was developed that directly addressed deficiencies and was used to train health staff. Changes in the management of AD/D were assessed by re-auditing case notes. There were learning needs among health staff in the management of AD/D. Altogether, 34 (97.1%) of 35 residents were trained. Training resulted in modest improvements in the number of children in whom nutritional status was assessed, use of oral rather than intravenous fluids for rehydration and reducing unnecessary laboratory tests. Training resulted in marked improvements in the correct volume of (pre- vs. post-training 6.3% vs. 94.1%, P<0.001) and follow-up of fluid therapy (8.1% vs. 98.0%; P<0.001), prescription of zinc (41.6% vs. 85.1%, P<0.001) and providing advice on when to return after discharge (77.6% vs. 96.0%, P<0.001). Although statistically significant, the minimal improvements in antibiotic use (43.8% vs. 56.6%, P = 0.03), re-starting feeds (10.6% vs. 38.6%, P<0.001) and counselling about feeding (11.8% vs. 33.7%, P<0.001) highlighted areas for further training. In low-resource countries, clinical auditing and training can significantly improve the management of illnesses that contribute to child deaths and identify areas where further training is required.

Transcriptome Analysis of Al-Induced Genes in Buckwheat (Fagopyrum esculentum Moench) Root Apex: New Insight into Al Toxicity and Resistance Mechanisms in an Al Accumulating Species

PubMed Central

Xu, Jia Meng; Fan, Wei; Jin, Jian Feng; Lou, He Qiang; Chen, Wei Wei; Yang, Jian Li; Zheng, Shao Jian

2017-01-01

Relying on Al-activated root oxalate secretion, and internal detoxification and accumulation of Al, buckwheat is highly Al resistant. However, the molecular mechanisms responsible for these processes are still poorly understood. It is well-known that root apex is the critical region of Al toxicity that rapidly impairs a series of events, thus, resulting in inhibition of root elongation. Here, we carried out transcriptome analysis of the buckwheat root apex (0–1 cm) with regards to early response (first 6 h) to Al stress (20 μM), which is crucial for identification of both genes and processes involved in Al toxicity and tolerance mechanisms. We obtained 34,469 unigenes with 26,664 unigenes annotated in the NCBI database, and identified 589 up-regulated and 255 down-regulated differentially expressed genes (DEGs) under Al stress. Functional category analysis revealed that biological processes differ between up- and down-regulated genes, although ‘metabolic processes’ were the most affected category in both up- and down-regulated DEGs. Based on the data, it is proposed that Al stress affects a variety of biological processes that collectively contributes to the inhibition of root elongation. We identified 30 transporter genes and 27 transcription factor (TF) genes induced by Al. Gene homology analysis highlighted candidate genes encoding transporters associated with Al uptake, transport, detoxification, and accumulation. We also found that TFs play critical role in transcriptional regulation of Al resistance genes in buckwheat. In addition, gene duplication events are very common in the buckwheat genome, suggesting a possible role for gene duplication in the species’ high Al resistance. Taken together, the transcriptomic analysis of buckwheat root apex shed light on the processes that contribute to the inhibition of root elongation. Furthermore, the comprehensive analysis of both transporter genes and TF genes not only deep our understanding on the responses

Transcriptome Analysis of Al-Induced Genes in Buckwheat (Fagopyrum esculentum Moench) Root Apex: New Insight into Al Toxicity and Resistance Mechanisms in an Al Accumulating Species.

PubMed

Xu, Jia Meng; Fan, Wei; Jin, Jian Feng; Lou, He Qiang; Chen, Wei Wei; Yang, Jian Li; Zheng, Shao Jian

2017-01-01

Relying on Al-activated root oxalate secretion, and internal detoxification and accumulation of Al, buckwheat is highly Al resistant. However, the molecular mechanisms responsible for these processes are still poorly understood. It is well-known that root apex is the critical region of Al toxicity that rapidly impairs a series of events, thus, resulting in inhibition of root elongation. Here, we carried out transcriptome analysis of the buckwheat root apex (0-1 cm) with regards to early response (first 6 h) to Al stress (20 μM), which is crucial for identification of both genes and processes involved in Al toxicity and tolerance mechanisms. We obtained 34,469 unigenes with 26,664 unigenes annotated in the NCBI database, and identified 589 up-regulated and 255 down-regulated differentially expressed genes (DEGs) under Al stress. Functional category analysis revealed that biological processes differ between up- and down-regulated genes, although 'metabolic processes' were the most affected category in both up- and down-regulated DEGs. Based on the data, it is proposed that Al stress affects a variety of biological processes that collectively contributes to the inhibition of root elongation. We identified 30 transporter genes and 27 transcription factor (TF) genes induced by Al. Gene homology analysis highlighted candidate genes encoding transporters associated with Al uptake, transport, detoxification, and accumulation. We also found that TFs play critical role in transcriptional regulation of Al resistance genes in buckwheat. In addition, gene duplication events are very common in the buckwheat genome, suggesting a possible role for gene duplication in the species' high Al resistance. Taken together, the transcriptomic analysis of buckwheat root apex shed light on the processes that contribute to the inhibition of root elongation. Furthermore, the comprehensive analysis of both transporter genes and TF genes not only deep our understanding on the responses of

Some TEM observations of Al2O3 scales formed on NiCrAl alloys