Heavy Metals Concentrations in the Shell and Tissue of Periwinkle (Tympanotonus fuscatus) and Giant Land Snail (Achatina fulica) in Soku Community of Niger Delta, Nigeria.

The pollution of aquatic ecosystem by heavy metals has assumed serious proportions due to their toxicity and accumulative behaviour. River dams are especially at risk of contamination by different contaminants from anthropogenic sources including heavy metals since change of sediment regime often occur. The accumulation of five heavy metals; chromium (Cr), Cadmium (Cd), Lead (Pb), Copper (Cu) and Arsenic (As) in periwinkle, (Tympanotonus fuscatus, var, radula) and giant land snail (Achatina fulica) shell and soft tissue collected from Soku Community, Akuku-toru Local Government Area of Rivers State, Nigeria. The periwinkle and giant land snail were processed and analyzed for heavy metals presence. Results obtained showed that the periwinkles accumulated more of these heavy metals than the snails. Copper and arsenic were the highest concentrated heavy metals in the periwinkle shell soft tissue. The concentration of copper and arsenic in periwinkles soft tissue was found to be l,612 mg/kg and 2.40 mg/kg respectively. In the giant land snail the soft tissue concentrated more of copper (277 mg/kg). These values exceeded set standards for guidelines on toxicity

Translation and narration: A corpus-based study of French translations of two novels by Virginia Woolf.

Narratology does not usually distinguish between original and translated fiction and narratologicai models do not pay any attention to the translator as a discursive subject. Since the 1990's, the visibility of translators in translated narrative texts has been increasingly discussed and researchers like Schiavi (1996) and Hermans (1996) introduced the concept of the translator's voice, which attempts to recognise the 'other' voice in translation, i.e. the presence of the translator. Corpus-based studies have also focused on recurrent features of translated language (see, for example. Baker 1993, Kenny 2001; Laviosa 1997; Olohan and Baker 2000), and corpus techniques and tools are being employed to identify the translators' 'style' in their translations (Baker 2000). The present thesis seeks to explore the nature of the translator's discursive presence by investigating certain narratologicai aspects of the relation between originals and translations. Until recently comparative analysis between originals and their translations have mainly relied on manual examinations; the present study will demonstrate that corpus-based translation studies and its tools can gready facilitate and sharpen the process of comparison. My work uses a parallel corpus composed of two English novels and their French translations; Virginia Woolf's To The Lighthouse (1927) and its three translations (Promenade au Phare, 1929, translated by Michel Lanoire; Voyage au Phare, 1993, by Magali Merle; Vers le Phare, 1996, by Francoise Pellan), and The Waves (1931), and its two translations (Les leagues, 1937, translated by Marguerite Yourcenar and Les agues, 1993, translated by Cecile Wajsbrot). The relevant texts have been scanned and put in machine-readable form and I study them using corpus-analysis tools and techniques (WordSmith Tools, Multiconcord). My investigation is particularly concerned with the potential problems involved in the translation of linguisdc features that constitute the notion of point of view, i.e. deixis, modality, transitivity and free indirect discourse, and seeks to determine whether and how the translator's choices affect the transfer of narratologicai structures

SEASONAL VARIATION OF HEAVY METALS CONCENTRATIONS IN FISH IN OGUTA LAKE, NIGERIA

Concentrations of heavy metals iron (Fe), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), chromium (Cr), cadmium (Cd) and arsenic (As), were determined in the head of four fish species, namely, Trachinotus goreensis, Clarias anguillaris, Synodontis membranaceous, and Tilapia zilli, in Oguta Lake, Nigeria. Result obtained from analyses using Atomic Absorption Spectrophotometry (AAS) revealed that Fe (13.309 mg/l) was the highest metal accumulated by the fish (S. membranaceous) in October, while Hg and As were not detected in all the fish species except in July where 0.003 and 0.005mg/l of As were detected in the fish species (T. zilli and C. anguillaris), and November where 0.001 mg/l of As was also detected in S. membranaceous. The distribution of HMs in the fish species revealed that, overall, Fe was the highest metal accumulated by the fish species, C. membranaceous, followed by T. goreensis. This high level of Fe accumulated by the fish species may be attributed to the fact that Fe occur at high levels in organic matter at the bottom of the Lake. So being typical bottom dwellers, the fish species were more exposed to the metal. Heavy metals were higher (not significantly) during the dry season than the rainy season. Statistically, however, seasonal variation didn’t significantly influence the accumulation of HMs by the fish species. The levels of heavy metals examined in the present study were below maximum permissible limits set by World Health Organization (WHO), indicating that the Oguta Lake is not polluted by heavy metals

Determination of Physicochemical Characteristics of Early Rain Water in a Rain Forest Region, Owerri, Nigeria.

Analysis of physicochemical characteristics of samples of rain water collected from rain gauges at two sampling stations at Orji and Umuchima-Ihiagwa in Owerri, Nigeria revealed that rain water from sampling station, Orji (RWSO) had the highest pH value (6.24), while values obtained for total suspended solids (14.23 mg/l-1), total dissolved solids (15.10 mg/l-1), calcium hardness (3.91 mg/l-1), and sulphate (11.23 mg/l-1) were highest for RWSO compared to values obtained from analysis of rain water sampling station, Umuchima (RWSU). However, it was observed that values obtained from nitrate analysis were almost equal (0.62, 0.60 mg/l-1 for RWSO and RWSU) for both sampling stations. Values obtained for the physicochemical parameters from both sampling stations were within World Health Organization (WHO) permissible standards for quality drinking-water

Influence of intensive melt shearing on the microstructure and mechanical properties of an Al-Mg alloy with high added impurity content

The official published version can be accessed from the link below - Copyright @ The Minerals, Metals & Materials Society and ASM International 2011We have investigated the influence of melt conditioning by intensive shearing on the mechanical behavior and microstructure of Al-Mg-Mn-Fe-Cu-Si alloy sheet produced from a small book mold ingot with high added impurity content. The melt conditioned ingot has fine grains throughout its cross section, whereas a conventionally cast ingot, without melt shearing, has coarser grains and shows a wider variation of grain size. Both needle-shaped and coarse Chinese script iron bearing intermetallic particles are found in the microstructure at the center of the conventionally processed ingot, but for the melt conditioned ingot, only fine Chinese script intermetallic particles are observed. In addition to the iron bearing intermetallics, Mg2Si particles are also observed. The ingots were rolled to thin sheet and solution heat treated (SHT). During rolling, the iron-based intermetallics and Mg2Si particles are broken and aligned along the rolling direction. Yield strength (YS), ultimate tensile strength (UTS), and elongation of the intensively melt sheared and processed sheet are all improved compared to the conventionally cast and processed sheet. Fractographic analysis of the tensile fracture surfaces shows that the clustered and coarse iron bearing intermetallic particles are responsible for the observed reduction in mechanical properties of the conventionally cast sheet. We have shown that by refining the initial microstructure of the ingot by intensive shear melt conditioning, it is possible to achieve improved mechanical properties at the final sheet gage of an AlMgMn alloy with a high content of impurities.This study is under the Technology Strategy Board funded REALCAR projec

Metabolomics, peptidomics and glycoproteomics studies on human schistosomiasis mansoni

The application of dedicated mass spectrometry (MS) and nuclear magnetic resonance (NMR) technologies for biomarker discovery and diagnostic purposes has increased substantially in the last decade. In the studies presented in this thesis, we have used these technologies to identify parasite or host-derived products (biomarkers) related to infection and morbidity associated with schistosomiasis and to better understand the host-parasite interaction. The application of our peptidomics and metabonomics studies on schistosomiasis have provided some novel, valuable information but they are obviously only the first step. In addition to the potential biomarkers identified with the global biomarker discovery approaches, we showed in this thesis that a more targeted approach, looking at glycosylation, also resulted in novel information on S. mansoni infection. We have identified and characterized a set of human Apolipoprotein C-III peptides aberrantly glycosylated at the O-glycosylation site (Thr74), in urine of S. mansoni- infected individuals. The presented study is the first in which MS and NMR were used for the analysis of a cohort of human S. mansoni-infected individuals. This has resulted in the identification of a number of novel markers. Nevertheless, further studies are needed to evaluate the overall applicability of these putative biomarkersThe printing of this thesis was financially supported by: Bruker Daltonics, Germany Dionex Benelux B.VUBL - phd migration 201

Kinetic Study of Aluminum Sulphate and Ammonium Aluminum Sulphate Coagulants in Wastewater Treatment

An investigation into the kinetics of two inorganic coagulant namely: aluminum sulphate octadecahydrate (Al2(SO4)3.18H2O) an ammonium aluminum sulphate dodecahydrate (NH4Al(SO4)2.12H2O) was studied to determine the effect of certain kinetic parameters on coagulation performance of the above mentioned coagulants. Results of analysis obtained revealed that the rate constant (k) for Al2(SO4)3.18H2O was 5.727s-1, while that for NH4Al(SO4)2.12H2O was 2.282s-1. However, the order of the reaction (xn) of Al2(SO4)3.18H2O and NH4Al(SO4)2.12H2O with the wastewater was 1.0 and 1.0, respectively, indicating that both reactions were first order. Considering the mechanism of the reaction, the general trend observed indicated that the Al2(SO4)3.18H2O reaction was thrice as fast as the NH4Al(SO4)2.12H2O reaction. This fact together with the larger value of k for Al2(SO4)3.18H2O obtained in the experiment lend credence to the widely held believe that Al2(SO4)3.18H2O is a more effective coagulant than NH4Al(SO4)2.12H2O in wastewater treatment

ASSESSMENT OF SEASONAL PHYSICO-CHEMICAL PARAMETERS OF OGUTA LAKE, NIGERIA.

Seasonal variation of physico-chemical variables of Oguta Lake, Nigeria was studied. Results obtained using standard analytical methods indicated that in the rainy and dry seasons (July and August) and (October and November), 2014, iron (Fe; 1.401 mg/l in November) was the overall metal observed in the lake, while mercury (Hg) was not detected throughout the period of study. Heavy metals concentrations observed were higher (not significantly) during the dry than the rainy season. The values observed for dissolved oxygen (DO), biological and chemical oxygen demand (BOD and COD) were within WHO permissible limits. The above evidence revealed that there was signs of heavy metal (Fe) pollution of the lake, and steps must be taking for constant monitoring of anthropogenic inputs into the lake.Â

SLC11A1 Gene Polymorphism in Adults Co-Infected with Helminth and Latent Tuberculosis in Yewa, Ogun State

Mutations in the 3’UTR and D543N regions of the solute carrier 11a1 protein (SLC11A1) gene have been found to strongly increase the risk of several diseases caused by intracellular organisms such as M. tuberculosis. The aim of this study was to screen for polymorphisms in the 3’UTR and D543N regions of SLC11A1 gene with the goal of understanding the genetic dynamics of tuberculosis and schistosomiasis co-infection in a Nigerian adult population. A cross-sectional study was carried out with 185 participants who were screened for intestinal and urinary helminthiases using microscopic examination of stool and urine respectively; latent tuberculosis using skin tuberculin test; and active tuberculosis using sputum microscopy. PCR-RFLP analyses were carried out on extracted DNA for detection of SLC11A1 gene polymorphisms. Participants filled questionnaires from which information on awareness, clinical and family histories and lifestyles were obtained. There were no polymorphisms observed. 32% had urinary schistosomiasis and 0.1% had intestinal helminthiasis suggesting that both types of infections could occur independently in the same population. The prevalence of coinfection with schistosomiasis and tuberculosis was 6.5%. This observation suggests an immunomodulation during schistosomiasis and latent tuberculosis co-infection. The absence of polymorphisms did not support the hypothesis that co-infection with schistosomiasis and latent tuberculosis might play a role as a risk factor during the development of active tuberculosis

Seasonal drought limits tree species across the Neotropics

Within the tropics, the species richness of tree communities is strongly and positively associated with precipitation. Previous research has suggested that this macroecological pattern is driven by the negative effect of water-stress on the physiological processes of most tree species. This process implies that the range limits of taxa are defined by their ability to occur under dry conditions, and thus in terms of species distributions it predicts a nested pattern of taxa distribution from wet to dry areas. However, this ‘dry-tolerance’ hypothesis has yet to be adequately tested at large spatial and taxonomic scales. Here, using a dataset of 531 inventory plots of closed canopy forest distributed across the Western Neotropics we investigated how precipitation, evaluated both as mean annual precipitation and as the maximum climatological water deficit, influences the distribution of tropical tree species, genera and families. We find that the distributions of tree taxa are indeed nested along precipitation gradients in the western Neotropics. Taxa tolerant to seasonal drought are disproportionally widespread across the precipitation gradient, with most reaching even the wettest climates sampled; however, most taxa analysed are restricted to wet areas. Our results suggest that the ‘dry tolerance’ hypothesis has broad applicability in the world's most species-rich forests. In addition, the large number of species restricted to wetter conditions strongly indicates that an increased frequency of drought could severely threaten biodiversity in this region. Overall, this study establishes a baseline for exploring how tropical forest tree composition may change in response to current and future environmental changes in this region