River Sediment Sampling and Environment Quality Standards: A Case Study of the Ravensbourne River

Sediment is a major sink for heavy metals in river, and poses significant risks not only to river quality but also to aquatic and benthic organisms. At present in the UK, there are no mandatory sediment quality standards. This is partly due to insufficient toxicity data but also due to problems with identification of appropriate sediment monitoring and analytical techniques. The aim of this research was to examine the sampling different river sediment compartments in order to monitor compliance with any future UK sediment environmental quality standards (EQS). The significance of sediment physical and chemical characteristics on sampling and analysis was also determined. The Ravensbourne River, a tributary of the River Thames located in the highly urbanised South Eastern area of London was used for this study. Sediment was collected from the bed using the Van Veer grab, the bank using hand trowel, and from the water column (suspended sediment) using the time integrated suspended tube sampler between the period of July 2010 and December, 2011. The result for the total metal extraction carried out using aqua regia found that there were no significant differences in the metal concentrations retained in the different compartments by the <63μm sediment fraction but there were differences between the 63μm-2mm fractions of the bed and bank. The metal concentration in the bed, bank and suspended sediment exceeded the draft UK sediment quality guidelines. Sequential extraction was also carried out to determine metal speciation in each sediment compartment using the Maiz et al. (1997) and Tessier et al. (1979) methods. The Maiz et al. (1997) found over 80% of the metals in each sediment compartment were not bioavailable, while Tessier et al. (1979) method found most of the metals to be associated with the Fe/Mn and the residual phase. The bed sediment compartment and the <2mm (<63μm + 63μm-2mm) fraction appears to be the most suitable sediment sample for sediment monitoring from this study

PRINCIPALS’ OPENNESS AND AGREEABLENESS AS CORRELATE OF THEIR ADMINISTRATIVE EFFECTIVENESS IN SECONDARY SCHOOLS IN ANAMBRA STATE

This study investigated principals’ openness and agreeableness as correlate of their administrative effectiveness in secondary schools in Anambra State. Two research questions guided the study and two hypotheses were tested at 0.05 level of significance. A correlational survey research design was adopted for the study. The population of the study consisted all the 263 principals in the six education zones of Anambra State. All the principals were used for the study. Two sets of researchers’-developed instrument titled “Principals’ Openness and Agreeableness Questionnaire” (POAQ) and “Principals’ Administrative Effectiveness Questionnaire” (PAEQ) were used for data collection. The instruments were validated by three experts and subjected to internal consistency test using Cronbach’s Alpha method which yielded 0.81 for POAQ and 0.89 for PAEQ. Pearson’ Product Moment Correlation Co-efficient was used to analyze data for the study. The findings of the study indicated that there is a strong positive relationship between principals’ openness and agreeableness and their administrative effectiveness in secondary schools in Anambra State. Based on the findings it was recommended among others that there is need for Post Primary School Service Commission to determine the personality traits of would be principals before their appointment to ensure they possess requisite traits to manage the affairs of the schools for effectiveness

Mobile Transactions Architecture: Lagos---rethinking the drive through market

MOBILE TRANSACTIONS ARCHITECTURE learns from Lagos' "publiccongestion" infrastructures to create a new architectural typology: The drive through market, an intensification of the interchange market phenomenon. It anticipates a greater densification of the Lagos megalopolis by appropriating the site of future superstructure abutments connecting the Island to the mainland. The principal design approach renegotiates and de-optimizes the existing motorway interchange geometry and technology to facilitate a flexible and dynamic public space of both mobility and commerce activity, giving Lagos a liberating opportunity to legitimize informal street trade and regularize its economy. This thesis projects an ambition for an architecture of percolation, a flowscape that simultaneously accommodates conveyance and interaction to facilitate an unprecedented magnitude of collective inhabitation

Power to identify a genetic predictor of antihypertensive drug response using different methods to measure blood pressure response

<p>Abstract</p> <p>Background</p> <p>To determine whether office, home, ambulatory daytime and nighttime blood pressure (BP) responses to antihypertensive drug therapy measure the same signal and which method provides greatest power to identify genetic predictors of BP response.</p> <p>Methods</p> <p>We analyzed office, home, ambulatory daytime and nighttime BP responses in hypertensive adults randomized to atenolol (N = 242) or hydrochlorothiazide (N = 257) in the Pharmacogenomic Evaluation of Antihypertensive Responses Study. Since different measured BP responses may have different predictors, we tested the "same signal" model by using linear regression methods to determine whether known predictors of BP response depend on the method of BP measurement. We estimated signal-to-noise ratios and compared power to identify a genetic polymorphism predicting BP response measured by each method separately and by weighted averages of multiple methods.</p> <p>Results</p> <p>After adjustment for pretreatment BP level, known predictors of BP response including plasma renin activity, race, and sex were independent of the method of BP measurement. Signal-to-noise ratios were more than 2-fold greater for home and ambulatory daytime BP responses than for office and ambulatory nighttime BP responses and up to 11-fold greater for weighted averages of all four methods. Power to identify a genetic polymorphism predicting BP response was directly related to the signal-to-noise ratio and, therefore, greatest with the weighted averages.</p> <p>Conclusion</p> <p>Since different methods of measuring BP response to antihypertensive drug therapy measure the same signal, weighted averages of the BP responses measured by multiple methods minimize measurement error and optimize power to identify genetic predictors of BP response.</p

A palaeoenvironmental study of particle size-specific connectivity- new insights and implications from the West Sussex Rother Catchment, United Kingdom

Connectivity has become an important conceptual and practical framework for understanding and managing sediment transfers across hillslopes, between hillslopes and rivers and between rivers and other compartments along the river corridor (e.g. reservoirs, channel substrate, floodplain). Conventionally, connectivity focuses on the quantity of sediment transferred but here we also consider the size of the finer sediment (typically particles < 500 µm diameter). We examine the role of small rapidly silting reservoirs in the River Rother on storing sediment and disrupting downstream sediment transfers. Spatial and temporal changes in the particle size characteristics of sediment deposited in one of the ponds is explored in detail. Downstream of this pond we collected sediment from the river on nine occasions over 17 months using two sampling methods at two locations; one immediately downstream of the pond and a second ~700 m further downstream but upstream of the confluence with the Rother. Results showed a significant depletion in sand sized particles immediately downstream of the pond but the sand had been recovered from an in-channel source before the river reached the downstream sampling point

Trace metal distribution in the bed, bank and suspended sediment of the Ravensbourne River and its implication for sediment monitoring in an urban river

Purpose This study aims to identify a suitable sediment compartment for sediment quality monitoring by: (a) studying the concentration of trace metals (Cd, Cu, Ni, Pb and Zn) in the bed, bank and suspended sediment compartments of the Ravensbourne River to establish any differences in trace metal concentrations with compartment; (b) determining the influence of sediment particle size fractions ( 0.05) in the concentrations of metals between the suspended sediment and the < 63 μm bed sediment fraction, but there was a significant difference (p < 0.05) between the suspended sediment and the < 63 μm bank sediment fraction. There were also significant differences between the concentrations of metals in the < 63 μm and the 63 μm–2 mm fractions. Generally, the Ravensbourne River did not comply with the draft UK sediment quality guidelines for the metals analysed. Conclusions This study shows the importance of identifying a suitable sediment compartment to sample for compliance with sediment quality standards. The bed and suspended sediments are the most widely used sediment compartments for sediment monitoring, but collecting sufficient mass of the < 63 μm sediment fraction for monitoring presents a challenge for urban gravel bed rivers like the Ravensbourne River. It seems appropriate to establish individual monitoring regimes for different rivers

Aimé Césaire : un être de papier dans le roman antillais contemporain

This paper aims to scrutinize various aspects in which Aimé Césaire is represented in the Caribbean novel as a personage, on the basis of Théorie et fiction by Milagros Ezquerro. We discover that, because of the great halo and notoriety of the eminent cultural and political figure that he was, Aimé Césaire has been put on stage by several Caribbean novelists. So Césaire has become a literary material, as well as a theme with various patterns

Relationship between Success Attributions and Academic Achievement of Secondary School Students in Anambra State, Nigeria

The study focused on the relationship between success attributions and academic achievement of secondary school students in Anambra State. Six research questions and six null hypotheses guided the study. Using a multi-stage sampling technique, the study adopted a correlation design with a sample size of 600 senior secondary two students drawn from the population of 11,417 co-educational students. The instrument for data collection was the Students’ Attribution Style Questionnaire. Students’ Achievement Scores were used to obtain students’ academic achievement. The reliability of the instrument was established using the Cronbach Alpha method, which yielded a reliability of .84. The Pearson Product Moment correlation was used to answer the research questions, while the t-test of the significance of the correlation was used to test the null hypotheses at a .05 level of significance. Findings from the study revealed a medium positive correlation between attributions and academic achievement scores of students with internal success attributions. Also, the finding revealed a significant relationship between attributions and academic achievement scores of students with internal success attributions. Based on these findings, it was recommended that teachers always emphasize the effort to adopt the success attribution approach in the learning process as the basis for students’ success in their academic activities and also improve the learning environment to minimize environmental constraints