96 research outputs found
Is South Africa on the road to achieving sustainable agriculture? : An environmental law perspective
No full textIncludes bibliographical references.The appearance and development of the concept of sustainable agriculture in international legal discourse has taken place in a period of human history characterised by elevated understanding of the complex relationship between humanity and its surrounding environment
Transport & urban planning in New Zealand : a constant balance of conflict of interests
No full textThis article is in response to an article published in the previous edition of Lincoln University planning review 1(1), by Tim Cheesebrough. This reply considers future developments in transport and urban planning in New Zealand, in particular the role of public transport and how to reduce dependence on motor vehicles
The Search for Very High Energy γ-rays from Misaligned AGN
No full textThe aim of this work is to study the potential for emission at very high energies (100 GeV) by misaligned active galactic nuclei (AGN) and the future prospects for observations of these objects with the next generation imaging atmospheric Cherenkov telescope, the Cherenkov Telescope Array (CTA). Initially, data collected by the H.E.S.S. array was used to study fourteen Seyfert galaxies
and two other AGN with Seyfert-like properties and no new detections were reported. For each object upper limits were calculated, assuming a similar spectral shape to M87.
Further work focused on modelling the GeV spectra of misaligned AGN (AGN with angles of inclination to the line of sight 5◦ ) detected in 2010 with the Fermi Space Telescope. The modelling was carried out using a multiblob model that had previously been used to model the very high energy emission of M87 and Centaurus A. This work was used to investigate the capacity of the model to reproduce the high energy spectra observed for each object, while also allowing predictions of the potential very high energy fluxes to be produced. In each case the multiblob model was able to reproduce the observed GeV spectrum. The spectral energy distributions produced were then compared to predicted sensitivity curves for a number of possible CTA configurations to determine the likelihood of detection of these misaligned AGN with the array. It was found that detection of the objects within 50 hours of observations with CTA using standard Durham analysis is unlikely, but that 3C 111 may be detectable using the Paris analysis method
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The Impact of Welfare Reform Time Limits on Children and Families: Implications for Reauthorization
No full textThe passage of the Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) in 1996 abolished the Aid to Families with Dependent Children (AFDC) program, and replaced the AFDC cash assistance entitlement with the Temporary Assistance to Needy Families (TANF) program. With the creation of TANF, behavioral mandates such as time limits were imposed so that for the first time welfare recipients were limited to a maximum of five years of federal cash assistance in a lifetime. In order to determine the impact of time limits on children and families, the present paper explores time limits from both a theoretical and an empirical perspective. After a careful review of both the theoretical work of Grogger et al. (1999, 2000) as well as four state-level evaluations, the paper finds that many of the studies reviewed understate the real impact of time limits on children and families across several measurable outcomes. The paper con cludes with recommendations for the upcoming welfare reauthorization debate, including the abolition of time limits, or if abolition is not possible, to carefully apply best practice policies such as earned income disregards, automatic Food Stamp and Medicaid enrollment (or at the very least, mandated outreach), and generous exemption and extension policies in all states
Successful Contracting of Production Facilities for Al Shaheen Field, Offshore Qatar
No full textAbstract
In 1992 Qatar Petroleum signed an Exploration and Production agreement with Maersk Oil Qatar AS regarding the development of the Al Shaheen field offshore Qatar. Production commenced in 1994 via early production facilities, and by late 2005, when 18 permanent platforms had been installed through earlier field development plans, the Field Development Plan 2005 (FDP 2005) was initiated.
FDP 2005 required 15 additional platforms (with a total dry weight of 125,000 tonnes), 24 inter field pipelines (with a total installed length of 240 Kms) and 5 subsea power cables (with a total installed length of 50 Kms) to be installed and connected offshore with the existing platform facilities in full production and executing a 6 rig, 163 well drilling campaign at the same time. In addition to prepare the existing facilities for the integration with the new FDP 2005 facilities, approximately 4 Million man hours of Brownfield work was required. The overall offshore work was completed with a production “up time” of 99.7%, Remarkable.
Personnel safety and environmental protection are essential and constant considerations within Maersk Oil Qatar and therefore the safety performance of FDP 2005 was a source of great satisfaction; more than 55 Million construction man hours were expended on the project, both onshore and offshore, without any fatalities and with an achieved overall LTIF of less than 0.3.</jats:p
Hookworm Infection in Edo State, Nigeria
No full textThe main objective of this study is to determine the prevalence of infection, geographical, seasonal and age group distribution of the parasites in the state. The study which was prospective and cross-sectional, lasted during the period May 2008 to April 2009. The study was carried out in all the Local Government Areas in Edo state. The participants were one hundred children drawn randomly from primary and junior secondary schools and twenty adult farmers in the community. Stool samples were collected from the participants for analysis. Identification of parasites was by examination of direct fecal smear with the light microscope after the method of Cheesebrough. The prevalence of hookworm parasites was 3.5%. There was a significant age difference in infection rate between ages 1year-50yrs.and 51-80 yrs (p<0.05). Other intestinal parasites found were Ascaris lumbricoides, Trichuris trichiura and Entamoeba coli. There was no significant difference in both monthly prevalence and in the various local government areas (p > 0.05). However, there was a significant difference in infection rate between ages one year to fifty years and fifty one years to eighty years. Software package was (Gen Stat Release 8.1). The study identified hookworm infection as a disease which largely affects children and farmers as a result of habit and occupation. Control measures should therefore be targeted at children and farmers who are much predisposed to the infection.Keywords: Prevalence; hookworm infection; skin penetration, endemicityNigerian Journal of Parasitology, Vol. 33 [1] March 2012, pp. 67-7
Whole-genome comparison of two Campylobacter jejuni isolates of the same sequence type reveals multiple loci of different ancestral lineage
No full textCampylobacter jejuni ST-474 is the most important human enteric pathogen in New Zealand, and yet this genotype is rarely found elsewhere in the world. Insight into the evolution of this organism was gained by a whole genome comparison of two ST-474, flaA SVR-14 isolates and other available C. jejuni isolates and genomes. The two isolates were collected from different sources, human (H22082) and retail poultry (P110b), at the same time and from the same geographical location. Solexa sequencing of each isolate resulted in 1.659 Mb (H22082) and 1.656 Mb (P110b) of assembled sequences within 28 (H22082) and 29 (P110b) contigs. We analysed 1502 genes for which we had sequences within both ST-474 isolates and within at least one of 11 C. jejuni reference genomes. Although 94.5% of genes were identical between the two ST-474 isolates, we identified 83 genes that differed by at least one nucleotide, including 55 genes with non-synonymous substitutions. These covered 101 kb and contained 672 point differences. We inferred that 22 (3.3%) of these differences were due to mutation and 650 (96.7%) were imported via recombination. Our analysis estimated 38 recombinant breakpoints within these 83 genes, which correspond to recombination events affecting at least 19 loci regions and gives a tract length estimate of 2 kb. This includes a 12 kb region displaying non-homologous recombination in one of the ST-474 genomes, with the insertion of two genes, including ykgC, a putative oxidoreductase, and a conserved hypothetical protein of unknown function. Furthermore, our analysis indicates that the source of this recombined DNA is more likely to have come from C. jejuni strains that are more closely related to ST-474. This suggests that the rates of recombination and mutation are similar in order of magnitude, but that recombination has been much more important for generating divergence between the two ST-474 isolates
Radio imaging of the very-high-energy gamma-ray emission region in the central engine of a radio galaxy
No full textThe accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10^12 electron Volts (eV) and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy M87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.The VERITAS Collaboration, the VLBA 43 GHz M87 Monitoring Team, the H.E.S.S. Collaboration, the MAGIC Collaboratio
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