Adaption of structured analysis design techniques methodology for construction project planning

The construction industry has been heavily criticised by researchers and governmental organisations for its performance especially excessive delay. Ballard and Howell (2003) indicated that only about 50% of the tasks on weekly work plans are completed by the end of the plan week. This is a result of a lack of either effective project planning or effective production control. It therefore seems the traditional approach of planning is insufficient to meet the current demand and complexity of construction projects. This paper proposes to critically evaluate the adaptation of Structured Analysis Design Techniques (SADT) methodology as a tool for project planning. SADT which was further developed into IDEF (Integrated Definition) techniques claims to be a complete methodology to provide the means of understanding complex production systems and aid the implementation of change. The use of this methodology has led to process improvement. The research uses a literature review followed by interviews with academics and practitioners to investigate their knowledge and understanding of SADT (IDEFO). The results of the interviews indicated that SADT (IDEFO) methodology is seldom known and used in the construction industry. However, this study indicates that SADT methodology appears to be an effective project planning tool. This study contributes to the limited project planning techniques in construction industry by exploring the possible adaption of SADT

A Review of the Anticancer Potential of the Antimalarial Herbal Cryptolepis Sanguinolenta and its Major Alkaloid Cryptolepine

Cryptolepis sanguinolenta (Lindl.) Schltr (Periplocaceae), has a longstanding traditional use in the treatment of malaria in the West African region. Recent evidence suggests that the aqueous extract from the roots and the major alkaloid from the plant, cryptolepine, have prospects as cancer chemotherapeutic agents on account of their potent cytotoxicity to mammalian cells. Several mechanisms have been proposed to explain the cytotoxic activities of the agents. However, emerging evidence from their anti-inflammatory actions suggest that the mechanism of the cytotoxicity may be closely related to its antiinflammatory activity. This review looks at the mechanisms of cryptolepis-induced cytotoxicity, its link with inflammation and its potential as anticancer agent. The elucidation of these interwoven mechanisms may be useful in the development of cryptolepine or other analogues as new anticancer agents

Analysis of the Detection of Organophosphate Pesticides in Aqueous Solutions Using Hydrogen-Bond Acidic Coating on SH-SAW Devices

The work presented in this paper focuses on the synthesis and characterization of a hybrid organic/inorganic chemically sensitive layer for rapid detection and analysis of OPs in aqueous solutions using SH-SAW devices. Coated SH-SAW devices on 36° YX-LiTaO and 42.75° YX-Quartz (ST-90° X Quartz), are used to determine the optimum operating conditions for achieving rapid sensor responses with high sensitivity. Three analytes (parathion-methyl, parathion, and paraoxon), having similar molecular mass and volume, are used to evaluate the performance of the hybrid organic/inorganic coating in terms of sensor properties of interest including sensitivity, selectivity, reproducibility. It is shown that the coating has a high degree of partial selectivity and sensitivity towards the analytes. With the present non-optimized chemical sensor, a limit of detection of 60 (ppb), 20 (ppb) and 100 (ppb) is estimated for parathion-methyl, parathion, and paraoxon, respectively, when using a 0.5 -thick BPA-HMTS sensing layer. Concentrations as low as 500 (ppb) parathion have been measured. This concentration is significantly much lower than the typical concentrations found on agricultural produce (≥10 ppm)

Emerging Physico-Chemical Methods for Biomass Pretreatment

A major challenge to commercial production of cellulosic ethanol pertains to the cost-effective breakdown of the complex and recalcitrant structure of lignocellulose into its components by pretreatment methods—physical, chemical, physico-chemical, biological and various combinations thereof. The type and conditions of a pretreatment impacts both upstream processes such as size reduction as well as downstream processes such as enzymatic hydrolysis and enzyme loadings, and as such the choice of a pretreatment method for a specific biomass (or mix of materials) is influenced by several factors such as carbohydrate preservation and digestibility, sugar and ethanol yields, energy consumption, equipment and solvent costs, lignin removal and quality, formation of sugar/lignin degradation products, waste production, and water usage, among others. This chapter reviews both well-known and emerging physico-chemical methods of biomass fractionation with regards to process description and applications, advantages and disadvantages, as well as recent innovations employed to improve sugar yields, environmental sustainability and process economics

Measuring The Usefulness Of Information For Investors Inferences: The Case Of Quarterly Earnings Announcements

In this paper, we propose a new method for assessing the usefulness of information, its inferential value. In the context of accounting and finance, we define the inferential value of information about a firm as how efficaciously the information enables investors to draw correct inferences regarding its future financial performance. On the basis of this definition, we develop a stylized model to measure the proximity of a firm’s future realized rates of return to the estimated rates of return implied by its current stock price. We then use the new measure to test the hypothesis that quarterly earnings announcements have a higher inferential value than other information arriving during interim (non-earnings announcement) periods. Our empirical findings suggest that investors are able to make more informative inferences about a firm’s future profitability based on quarterly earnings announcement than based on information available during interim periods. However, our findings also suggest that, in general, investors do not correctly anticipate future losses. Finally, we find that earnings announcements are as important in anticipating future profitability for larger firms as they are for smaller firms

Nanoparticle growth following photochemical α‐ and β‐pinene oxidation at Appledore Island during International Consortium for Research on Transport and Transformation/Chemistry of Halogens at the Isles of Shoals 2004

Nanoparticle events were observed 48 times in particle size distributions at Appledore Island during the International Consortium for Atmospheric Research on Transport and Transformation/Chemistry of Halogens on the Isles of Shoals (ICARTT/CHAiOS) field campaign from 2 July to 12 August of 2004. Eighteen of the nanoparticle events showed particle growth and occurred during mornings when peaks in mixing ratios of α‐ and β‐pinene and ozone made production of condensable products from photochemical oxidation probable. Many pollutants and other potential precursors for aerosol formation were also at elevated mixing ratios during these events, including NO, HNO3, NH3, HCl, propane, and several other volatile organic carbon compounds. There were no consistent changes in particle composition, although both submicron and supermicron particles included high maximum concentrations of methane sulfonate, sulfate, iodide, nitrate, and ammonium during these events. Nanoparticle growth continued over several hours with a nearly linear rate of increase of diameter with time. The observed nanoparticle growth rates varied from 3 to 13 nm h−1. Apparent nanoparticle aerosol mass fractions (yields) were estimated to range from less than 0.0005 to almost 1 using α‐ and β‐pinene as the presumed particle source. These apparent high aerosol mass fractions (yields) at low changes in aerosol mass are up to two orders of magnitude greater than predictions from extrapolated laboratory parameterizations and may provide a more accurate assessment of secondary organic aerosol formation for estimating the growth of nanoparticles in global models

Book Reviews

This issue of the CJAS includes reviews of two important books: The Mind of Africa by William Abraham, that was recently re-issued in paperback, and Building the Nation: Seven Notable Ghanaians, edited by Mercy Akrofi- Ansah and Esi Sutherland-Addy. We think that these commentaries provide critical illumation of these important texts, and we are grateful to Professor Emeritus Ivan Addae-Mensah, and Drs Amoah-Boampong and Richmond Kwesi for their thoughtful reflections