Analysis of genes controlling notochord development in zebrafish.

The notochord is a vital and defining organ in vertebrates. Mutagenesis screening in zebrafish identified seven 'dwarf mutants that lack notochord development grumpy, sleepy, bashful, dopey, happy, sneezy and doc. This thesis is concerned with the identification and positional cloning of the doc locus as well as the confirmation and characterisation of the dopey and happy loci. Previous positional cloning efforts identified the grumpy, sleepy and bashful genes, demonstrating a requirement for the laminin chains pi, yl and al in formation of the notochord basement membrane (Parsons et al., 2002b Pollard, 2002) and the mutant sneezy, which has been shown to encode the COPI subunit a (Coutinho et al., 2004). This thesis establishes that the doc locus lies within a 0.5Mb region on linkage group 18, containing several genes, including a novel gene encoding a predicted protein with 14 WD40 domains. Antisense morpholino (MO) knock-down of doc results in a phenocopy of doc and insitu expression demonstrates that this gene is expressed specifically within the notochord during development. Expression analysis of echidna hedgehog (ehh) demonstrated that MO knock-down of this gene results in a lack of notochord differentiation. I therefore expect this novel gene is doc. Analysis of the mutants dopey and happy has demonstrated that they encode the coatomer subunits COPp' and COPp respectively. Expression of these and other COPI subunits demonstrate that the majority of COPI subunits are up-regulated within the notochord during development and maintained abnormally in COPI deficient embryos. I have investigated the mechanism of coatomer gene regulation and found that loss of coatomer function leads both to up-regulation of coatomer mRNA and activation of the unfolded protein response (UPR). Suggesting that the UPR is the regulator of mRNA expression, functioning to maintain the secretory network during development, though work to provide definitive proof remains

Turning on the heat: ecological response to simulated warming in the sea

Significant warming has been observed in every ocean, yet our ability to predict the consequences of oceanic warming on marine biodiversity remains poor. Experiments have been severely limited because, until now, it has not been possible to manipulate seawater temperature in a consistent manner across a range of marine habitats. We constructed a "hot-plate'' system to directly examine ecological responses to elevated seawater temperature in a subtidal marine system. The substratum available for colonisation and overlying seawater boundary layer were warmed for 36 days, which resulted in greater biomass of marine organisms and a doubling of space coverage by a dominant colonial ascidian. The "hot-plate'' system will facilitate complex manipulations of temperature and multiple stressors in the field to provide valuable information on the response of individuals, populations and communities to environmental change in any aquatic habitat

Health Personnel’s Perception On The Use Of Social Media In Healthcare Delivery System In Rural and Urban Communities of Oyo State, Nigeria

The study examined health personnel’s perception on the use of social media in healthcare delivery system in rural and urban communities of Oyo state, Nigeria. Randomly, 2 Local Government Area (LGA) each were selected from rural and urban LGA that represents 12% of LGA in the state, these are Ibarapa East, Iseyin, Ibadan North and Ogbomosho North.  Purposively, medical centres were sampled based on the concentration of health practitioners in selected health centres. A total of three medical centres each from Ibarapa East and Iseyin, while three medical centres were selected from Ibadan North and Ogbomoso North. In all, 112 health personnel were used from the 124 personnel sampled. A good number of the respondents were below 50 years, data obtained indicated that there were more female medical personnel (66.1%) than male (33.9%). All the respondents had more than one year of working experience with 33.9% of them having less than five years work experience. Majority (58.9%) are aware of social media and had the mean score of 16.70 ± 3.19.  Respondents have a high knowledge of social media (13.3± 2.67), favourably disposed to the use of social media in healthcare delivery (84.34±13.20). There exist a significant relationship between respondents’ knowledge (r = 0.267; p<0.05) and the perception of health personnel on the use of social media for health care delivery, while there is no significant difference ((F=0.956; p>0.05) in respondents’ perception of health personnel on the use of social media for health care delivery across the medical personnel interviewed. Social media encourages youth participation and consequently can promote energies of rural youths for innovative effort to use social media to bring healthcare to rural communities. Keywords: Social Media, Health personnel, Perception, Rural and Urban Communitie

Poor choices: the limits of competitive markets in the provision of essential services to low-income consumers

A major study of the problems faced by the poor in the market for seven essential services in the UK - energy, food, housing, water, telecoms, transport, and financial services. Together these represent 60% of spending by the poorest 30% of households

Impact of continuous mechanical harvesting on leaf leatheriness and possible alleviation measures

Mechanization in plucking has become imperative to improve the profitability and efficiency in tea industry. Continuous shear harvesting of tea shoots creates a stress on plant thereby changing the texture of the crop shoots termed as “leaf leatheriness”. Objective of the study was to generate data on the formation of leaf leatheriness due to continuous shear harvesting and to propose the remedial measures. A factorial block design experiment was conducted with a ‘Chinery’ clone UPASI-9. Results indicated that continuous shear harvesting for a period of six months resulted in the accumulation of total wax content when compared to the hand plucked crop shoots which contributed to the leatheriness of crop shoots. Significant increase in the banji content in the harvest was also noticed due to continuous shear harvesting. Foliar applied chemicals influenced the reduction in banji shoots in the shear harvested treatments. Among the foliar applied treatments, reduction in the total wax content in the continuously shear harvested plots was obtained by the foliar application of KNO3 (2%) + Urea (1%) followed by KNO3 (2%) and Ca(NO3)2 (2%) when compared with control. Study concluded that foliar application of KNO3 (2%) alone or in combination with Urea (1%) is beneficial in alleviating the leaf leatheriness caused due to continuous shear harvesting without deterioration of quality characteristics with a prophylactic effect to improve the yield of tea plants

New Longevity Record for Ivory Gulls (Pagophila eburnea) and Evidence of Natal Philopatry

Ivory gulls (Pagophila eburnea) have been listed as “endangered” in Canada and “near threatened” interna-tionally. In June 2010, we visited Seymour Island, Nunavut, Canada, where gulls were banded in the 1970s and 1980s. We recaptured and released two breeding gulls banded as chicks in 1983, confirming natal philopatry to this breeding colony. These gulls are more than 28 years old, making the ivory gull one of the longest-living marine bird species known in North America.La mouette blanche (Pagophila eburnea) figure sur la liste des espèces « en voie de disparition » sur la scène canadienne et des espèces « quasi menacées » sur la scène internationale. En juin 2010, nous sommes allés à l’île Seymour, au Nunavut, Canada, où des mouettes avaient été baguées dans le courant des années 1970 et 1980. Nous avons recapturé et relâché deux mouettes reproductrices qui étaient considérées comme des oisillons en 1983, ce qui nous a permis de confirmer la philopatrie natale de cette colonie de nidification. Ces mouettes blanches ont plus de 28 ans, ce qui en fait l’un des oiseaux aquatiques vivant le plus longtemps en Amérique du Nord

Coulomb blockade of strongly coupled quantum dots studied via bosonization of a channel with a finite barrier

A pair of quantum dots, coupled through a point contact, can exhibit Coulomb blockade effects that reflect an oscillatory term in the dots' total energy whose value depends on whether the total number of electrons on the dots is even or odd. The effective energy associated with this even-odd alternation is reduced, relative to the bare Coulomb blockade energy for uncoupled dots, by a factor (1-f) that decreases as the interdot coupling is increased. When the transmission coefficient for interdot electronic motion is independent of energy and the same for all channels within the point contact (which are assumed uncoupled), the factor (1-f) takes on a universal value determined solely by the number of channels and the dimensionless conductance g of each individual channel. This paper studies corrections to the universal value of (1-f) that result when the transmission coefficent varies over energy scales of the size of the bare Coulomb blockade energy. We consider a model in which the point contact is described by a single orbital channel containing a parabolic barrier potential, and we calculate the leading correction to (1-f) for one-channel (spin-split) and two-channel (spin-degenerate) point contacts in the limit where the single orbital channel is almost completely open. By generalizing a previously used bosonization technique, we find that, for a given value of the dimensionless conductance g, the value of (1-f) is increased relative to its value for a zero-thickness barrier, but the absolute value of the increase is small in the region where our calculations apply.Comment: 13 pages, 3 Postscript figure

Characterizing Scales of Genetic Recombination and Antibiotic Resistance in Pathogenic Bacteria Using Topological Data Analysis

Pathogenic bacteria present a large disease burden on human health. Control of these pathogens is hampered by rampant lateral gene transfer, whereby pathogenic strains may acquire genes conferring resistance to common antibiotics. Here we introduce tools from topological data analysis to characterize the frequency and scale of lateral gene transfer in bacteria, focusing on a set of pathogens of significant public health relevance. As a case study, we examine the spread of antibiotic resistance in Staphylococcus aureus. Finally, we consider the possible role of the human microbiome as a reservoir for antibiotic resistance genes.Comment: 12 pages, 6 figures. To appear in AMT 2014 Special Session on Advanced Methods of Interactive Data Mining for Personalized Medicin

Chemical and mineralogical characterization of Gidan Jaja iron ore, Zamfara State, Nigeria

The chemical and mineralogical characteristics of Gidan Jaja iron ore located in Zurmi Local Governmental Area of Zamfara State was carried out using X-ray Fluorescence (XRF) spectrometer, X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and Optical Microscope. The XRF results obtained revealed that Gidan Jaja Iron ore has an average content of 73.79 % Fe2O3, 0.52 % MnO, 17.50 % TiO2, 0.11 % CaO, 0.50 % Cr2O3, 3.84 % SiO2, 0.43 % Al2O3, 0.034 % CuO, 0.02 % NiO, 0.46 % PbO, 2.76 % LOI. Phosphorus and Sulphur were below limit of detection. XRD analysis revealed that the ore contained 56 % Ilmenite, 34 % Magnetite and 10 % Spinel minerals. Petrographic study using polarized light revealed that the iron bearing minerals are predominantly Ilmenite and Magnetite, with minor amount of hematite, spinel and quartz. The results obtained from SEM analysis showed that the iron bearing minerals are separated from other minerals in the ore by smooth grain boundaries. The quality of the ore was compared with ores from other part of Nigeria, and based on the results obtained in this research work, Gidan Jaja iron ore can be classified as high grade, low silica, ilmenite iron ore. Finally combined results from chemical and mineralogical characterization of the iron ore deposit indicated that, the iron ore can be a source of iron ore for use in iron production.Keywords: Chemical, Mineralogical, Characterization, Gidan Jaja, Iron or