Rainstorm Intensity–Duration–Frequency Model for Tarkwa, Ghana

Rainstorm intensity–duration–frequency relationship is a tool required for appropriate planning and designing of drainage systems. In this study, 22 years of annual peak daily rainstorm data distribution was tested to verify if it followed Lognormal, Gumbel, or Log Pearson Type III distribution. The distribution to which it belonged was used to build rainstorm intensity model of 0.5, 2, 5, 8, 10, 12, 15, 18, and 24 h durations. The findings revealed that the observed peak annual rainstorm followed Gumbel and Log Pearson Type III distributions at 0.05 significant level. Sherman rainstorm intensity model was also adopted and the parameters determined. Data generated with the Gumbel distribution function best fitted the Sherman model followed by those by log Pearson Type III. The rainstorm models developed with Sherman’s equation were recommended for use in the Tarkwa area. Keywords: Flood, Gumbel Distribution, Water Resources, Rainstor

Impact Of Lamda Cyhalothrin Pyrethroid Insecticide On The Uptake Of Cations And Anions By The Gills Of Freshwater Catfish Hybrid Juvenile

The impact o acute exposure of karate (Lambda cyhalothrin pyrethroid) insecticide was evaluatedin a 4 – day exposure period at 20, 40, 60 and 80 ppm to Heterobranchus bidosals(+) X Clarias gariepinus(&#9794;) fngerlingsshowed the 96-hlc 50 as 25.11 ppm. The threshold value was 25. 11 ppm. The gills of the exposed fish analyzed showed a significant decrease in all major cations and anions(C1-, Ca2+, Na+, K+, Mg2+) at P < 0.05). There was no inhibion of upake of the catons and anions (C1-, Ca2+ Na+, K+, Mg2+). Their uptakeincreased rapidly during the 24 hr period and dropped at 48hr and 72 hr and gradualy increased at the end of 96 hr showing that it was time dependent. During the exposure period the fish stood in upright position with their snouts above the water surface gasping for air. Other behavioral characteristics of the exposed fish were peeling of the skin, initial increase in opercula movement, curvature of the body, loss of balance, erratic swimming and quietness Based the outcome of this research and under similar experimental condition it is the recommendation of this research that this pyrethroid will affect the uptake of the major cations and anions. It further advises environmental officers, crop farmers and insecticides habitual users to be cautious on the use of thisinsecticide because of the resultant consequences of the misuse. Keywords: Karate, Uptake, Cations, Anions, Gills, Catfish, Toxicity Animal Research International Vol. 4 (1) 2007 pp. 591-59

Multiwavelength analysis of the Lyman alpha emitting galaxy Haro 2: relation between the diffuse Lyman alpha and soft X-ray emissions

In order to use Lyman alpha (Lya) emission as star formation tracer in cosmological studies, we must understand how the resonant scattering affects the escape fraction of the Lya photons. Thus, high spatial resolution multiwavelength studies of nearby Lya emitters, like Haro 2, are highly needed. For that purpose, we have used Chandra X-ray and HST (UV, optical and NIR) images of Haro 2, and STIS and ground-based spectral images along its major and minor axes, to characterize the Lya emission and the properties of the stellar population. The UV, Ha (Halpha) and FIR luminosities of the Haro 2 nuclear starburst are reproduced using evolutionary synthesis models assuming a young stellar population with ages ~3.5-5.0 Myr, affected by differential interstellar extinctions. The observed X-ray emission is attributed to gas heated by the mechanical energy released by the starburst (soft component) and a Ultra-Luminous X-ray source candidate (hard). Both compact and diffuse Lya components are observed. Whereas Lya is spatially decoupled from Balmer lines emission, Balmer decrement and UV continuum, the diffuse Lya component is spatially correlated with the diffuse soft X-ray emission. Moreover, unlike the compact one, diffuse Lya shows luminosities larger than predicted from Ha, assuming case B recombination and dust extinction as derived from Ha/Hbeta. We propose that, whereas the compact Lya emission is associated to the massive stellar clusters and is affected by outflows and dust extinction, the diffuse Lya originates in gas ionized by the hot plasma responsible for the soft X-ray radiation, as suggested by their spatial correlation and by the measured L(Ha)/LsoftX ratios. Calibration of Lya as star formation rate tracer should therefore include both effects (destruction vs. enhancement) to avoid biases in the study of galaxies at cosmological distances.Comment: Accepted for publication in A&A, 18 pages, 8 figures, 9 tables. If problems with quality of images, see http://www.cab.inta-csic.es/users/otih/haro2-v63.clean.pd

Physical properties and evolutionary state of the Lyman alpha emitting starburst galaxy IRAS 08339+6517

Though Lyman alpha emission (Lya) is one of the most used tracers of massive star formation at high redshift, a correct understanding of radiation transfer effects by neutral gas is required to properly quantify the star formation rate along the history of the Universe. We are embarked in a program to study the properties of the Lya emission (spectral profile, spatial distribution, relation to Balmer lines intensity,...) in several local starburst galaxies. We present here the results obtained for IRAS 08339+6517. Using evolutionary population synthesis models, we have characterized the properties of the starburst (UV continuum, Halpha, total infrared and X-ray emissions, etc.), which transformed 1.4e+8 Mo of gas into stars around 5-6 Myr ago. In addition to the central compact emission blob, we have identified a diffuse Lya emission component smoothly distributed over the whole central area of IRAS 08339+6517. This diffuse emission is spatially decoupled from the UV continuum, the Halpha emission or the Halpha/Hbeta ratio. Both locally and globally, the Lya/Halpha ratio is lower than the Case B predictions, even after reddening correction, with an overall Lya escape fraction of only 4%. We conclude that in IRAS 08339+6517 the resonant scattering of Lya photons by an outflowing shell of neutral gas causes their highly-efficient destruction by dust, which explains the low Lya escape fraction measured. These results stress again the importance of a proper correction of scattering and transfer effects when using Lya to derive the star formation rate in high-redshift galaxies.Comment: Accepted for publication in A&A, 17 pages, 13 figures, 8 tables. If problems with quality of images, see https://cloud.cab.inta-csic.es/public.php?service=files&file=%2Fotih%2Ffiles%2Foti_mas%2Firas%2Firas-v53.ack_referee.pd

A study of the potential of cloud/mobile BIM for the management of construction projects

Successful management of construction projects in the Building Information Modelling (BIM) era of the 21st Century should include intelligent systems to support construction project teams in making informed decisions. Project teams are routinely faced with contractual obligations to deliver projects to meet key construction parameters such as cost, time, quality and more recently stringent sustainability requirements. These sorts of pressures are no longer new as widely acknowledged by experienced project managers, contract administrators and clients. The poor performance of one or more of the aforementioned parameters will undoubtedly compromise the entire project, thus leading to the dissatisfaction of clients. This paper explores the use of mobile/cloud BIM in facilitating the adoption of an integrated approach to project delivery through automated or semi-automated dynamic information sharing processes with the ultimate goal of improving construction performance. The adopted methodology involved the use of an online-administered questionnaire survey and in-depth interviews. The study identifies the adoption and uptake of cloud/mobile BIM technologies and the benefits and barriers

Evaluation of the structural performance of low carbon concrete

Evaluation of the effect of embodied carbon reduction using an optimized design section for a ground beam, use of supplementary cementitious materials, and replacement of normal aggregatewith light weight aggregate on the mechanical properties of low-carbon concrete was carried out. A creep coefficient of 0.019 was estimated for a 365-day period on a change in section from 1 to 0.6 m2 on a proposed trapezoidal section for ground beam, which showed a negligible difference when compared to the normal rectangular section owing to a reduction in embodied carbon due to the associated reduction in concrete volume and reinforcement. Training of 81 low-carbon concrete data sets in MATLAB using artificial neural network for 100% cement replacement with ground granular base slag indicates good performance with a mean square error of 0.856. From the study, it was observed that the extent of carbonation depth in concrete evidenced the measure of compressivestrength formation based on the specific surface area of the binder and the water absorption rate of the aggregate, while enhancing the flexural strength of the low-carbon concrete required a cement-to supplementary-cementitious-material ratio of 0.8

Development of low carbon concrete and prospective of geopolymer concrete using lightweight coarse aggregate and cement replacement materials

The use of Ground Granulated Blast-furnace Slag (GGBS) as an alternative cement replacement material incombination with conventional coarse aggregate have been successful in the production of near green concrete.Undoubtedly, GGBS has exhibited good cementitious attributes, however, there are concerns with slow strengthdevelopment and workability owing to its non-pozzolanic activities as well as some degree of porositynotwithstanding the sustainability potential. Therefore, this study presents a lytag based geopolymer lightweightconcrete with high strength development, improved mechanical properties and reduced embodied carbon. Tofurther improve and enhance the potential production of green concrete, complete replacement of conventionalcoarse aggregate with a recycled lightweight aggregate from industrial waste was carried out. The geopolymerprecursors consisted of sodium hydroxide, sodium silicate, GGBS and silica fume to optimize the performance ofthe concrete at 60–80% cement replacement for a target design mix of 20, 30, 40, and 50 MPa. The performanceof lytag based geopolymer concrete was compared with that of non-geopolymer lytag based concrete (controlsamples). The results show a 42% increase in compressive strength for the geopolymer lightweight concrete anda 22% increase in ultimate compressive strain which is an indication of improved moment of resistance instructural design. The results also show a 46–61% reduction in embodied carbon for the use of non-geopolymerlytag based concrete and 69–77% reduction for lytag based geopolymer concrete. The geopolymer concretebetween 7 and 63 days of loading increases by 0.55% in creep strain compared with increases of 2.81% for non-geopolymerlytag based concrete and reduction to 27.96% for the normal weight concrete. Modulus of Elasticityreduces with age of loading for the geopolymer concrete during creep at 0.39% compared to reduction of 1.93%for non-geopolymer lytag based concrete and increase of 12% for the normal weight concrete

Trainee teachers' use of blogs as private reflections for professional development

A collaborative research project between Sheffield Hallam University and Nottingham Trent University in the UK investigated the use of blogs with trainee teachers as an alternative to reflective paper-based diaries. An action research case study, involving focus groups of post-graduate (secondary) trainee teachers (one group from each University) was undertaken to determine attitudes and perceptions of blogging as an appropriate tool to support reflective professional development. The findings indicate that the use of blogs by the trainee teachers had a positive impact overall, and provide concrete evidence of their development as emerging professional teachers. Unlike traditional paper-based systems, blogs provided ongoing opportunities for the tutor to assist the trainees in their development as reflective practitioners. This paper seeks to share the findings of this research which the authors believe could be applicable to other areas of Higher Education.</p

DADA: Degree-Aware Algorithms for Network-Based Disease Gene Prioritization

<p>Abstract</p> <p>Background</p> <p>High-throughput molecular interaction data have been used effectively to prioritize candidate genes that are linked to a disease, based on the observation that the products of genes associated with similar diseases are likely to interact with each other heavily in a network of protein-protein interactions (PPIs). An important challenge for these applications, however, is the incomplete and noisy nature of PPI data. Information flow based methods alleviate these problems to a certain extent, by considering indirect interactions and multiplicity of paths.</p> <p>Results</p> <p>We demonstrate that existing methods are likely to favor highly connected genes, making prioritization sensitive to the skewed degree distribution of PPI networks, as well as ascertainment bias in available interaction and disease association data. Motivated by this observation, we propose several statistical adjustment methods to account for the degree distribution of known disease and candidate genes, using a PPI network with associated confidence scores for interactions. We show that the proposed methods can detect loosely connected disease genes that are missed by existing approaches, however, this improvement might come at the price of more false negatives for highly connected genes. Consequently, we develop a suite called D<smcaps>A</smcaps>D<smcaps>A</smcaps>, which includes different uniform prioritization methods that effectively integrate existing approaches with the proposed statistical adjustment strategies. Comprehensive experimental results on the Online Mendelian Inheritance in Man (OMIM) database show that D<smcaps>A</smcaps>D<smcaps>A</smcaps> outperforms existing methods in prioritizing candidate disease genes.</p> <p>Conclusions</p> <p>These results demonstrate the importance of employing accurate statistical models and associated adjustment methods in network-based disease gene prioritization, as well as other network-based functional inference applications. D<smcaps>A</smcaps>D<smcaps>A</smcaps> is implemented in Matlab and is freely available at <url>http://compbio.case.edu/dada/</url>.</p

Mortality from external causes in Africa and Asia: evidence from INDEPTH Health and Demographic Surveillance System Sites.

BACKGROUND: Mortality from external causes, of all kinds, is an important component of overall mortality on a global basis. However, these deaths, like others in Africa and Asia, are often not counted or documented on an individual basis. Overviews of the state of external cause mortality in Africa and Asia are therefore based on uncertain information. The INDEPTH Network maintains longitudinal surveillance, including cause of death, at population sites across Africa and Asia, which offers important opportunities to document external cause mortality at the population level across a range of settings. OBJECTIVE: To describe patterns of mortality from external causes at INDEPTH Network sites across Africa and Asia, according to the WHO 2012 verbal autopsy (VA) cause categories. DESIGN: All deaths at INDEPTH sites are routinely registered and followed up with VA interviews. For this study, VA archives were transformed into the WHO 2012 VA standard format and processed using the InterVA-4 model to assign cause of death. Routine surveillance data also provide person-time denominators for mortality rates. RESULTS: A total of 5,884 deaths due to external causes were documented over 11,828,253 person-years. Approximately one-quarter of those deaths were to children younger than 15 years. Causes of death were dominated by childhood drowning in Bangladesh, and by transport-related deaths and intentional injuries elsewhere. Detailed mortality rates are presented by cause of death, age group, and sex. CONCLUSIONS: The patterns of external cause mortality found here generally corresponded with expectations and other sources of information, but they fill some important gaps in population-based mortality data. They provide an important source of information to inform potentially preventive intervention designs