Neuroactive substances and associated major muscle systems in Bucephaloides gracilescens (Trematoda : Digenea) metacercaria and adult

Cholinergic, serotoninergic and neuropeptidergic components of the nervous system were examined and compared in the progenetic metacercaria and adult gasterostome trematode, Bucephaloides gracilescens in order to provide baseline information on neuronal control of the musculature involved in egg-assembly. Enzyme cytochemistry and indirect immunocytochemical techniques interfaced with confocal scanning laser microscopy demonstrated all three classes of neuroactive substance throughout the central and peripheral nervous systems. A comparable orthogonal arrangement of the central nervous system (CNS) and peripheral array of nerve plexuses was observed in both metacercaria and adult. Staining patterns for cholinergic and peptidergic substances showed significant overlap, while the serotoninergic system was confined to a separate set of neurons. Immunostaining for FMRFamide-related peptides (FaRPs) was strong in the CNS and peripheral innervation to the attachment apparatus of metacercaria and adult but was only found in the innervation of the ootype in ovigerous adults, implicating FaRPs in neuronal control of the muscle of the female reproductive tract during egg-assembly.

Activation of waste MDF sawdust charcoal and its reactive dye adsorption characteristics

This paper reports an experimental investigation of converting waste medium density fibreboard (MDF) sawdust into chars and activated carbon using chemical activation and thermal carbonisation processes. The MDF sawdust generated during the production of architectural mouldings was characterised and found to have unique properties in terms of fine particle size and high particle density. It also has a high content of urea formaldehyde resin used as a binder in the manufacturing of MDF board. Direct thermal carbonisation and chemical activation of the sawdust by metal impregnation and acid (phosphoric acid) treatment prior to pyrolysis treatment were carried out. The surface morphology of the raw dust, its chars and activated carbon were examined using scanning electron microscopy (SEM). Adsorptive properties and total pore volume of the materials were also analysed using the BET nitrogen adsorption method. Liquid adsorption of a reactive dye (Levafix Brilliant red E-4BA) by the derived sawdust carbon was investigated in batch isothermal adsorption process and the results compared to adsorption on to a commercial activated carbon (Filtrasorb F400). The MDF sawdust carbon exhibited in general a very low adsorption capacity towards the reactive dye, and physical characterisation of the carbon revealed that the conventional chemical activation and thermal carbonisation process were ineffective in developing a microporous structure in the dust particles. The small size of the powdery dust, the high particle density, and the presence of the urea formaldehyde resin all contributed to the difficulty of developing a proper porous structure during the thermal and chemical activation process. Finally, activation of the dust material in a consolidated form (cylindrical pellet) only achieved very limited improvement in the dye adsorption capacity. This original study, reporting some unexpected outcomes, may serve as a stepping-stone for future investigations of recycle and reuse of the waste MDF sawdust which is becoming an increasing environmental and cost liability. (C) 2004 Elsevier Ltd. All rights reserved.

Adsorption Characteristics of Reactive Dyes in Columns of Activated Carbon

Abstract: Adsorption behaviour of reactive dyes in fixed-bed adsorber was evaluated in this work. The characteristics of mass transfer zone (MTZ), where adsorption in column occurs, were affected by carbon bed depth and influent dye concentration. The working lifetime (t(x)) of MTZ, the height of mass transfer zone (HMTZ), the rate of mass transfer zone (RMTZ), and the column capacity at exhaustion (q(column)) were estimated for the removal of remazol reactive yellow and remazol reactive black by carbon adsorber. The results showed that column capacity calculated at 90% of column exhaustion was lower than carbon capacity obtained from equilibrium studies. This indicated that the capacity of activated carbon was not fully utilized in the fixed-bed adsorber. The bed-depth service time model (BDST) was applied for analysis of reactive yellow adsorption in the column. The adsorption capacity of reactive yellow calculated at 50% breakthrough point (No) was found to be 0.1 kg kg(-1) and this value is equivalent to about 14% of the available carbon capacity. The results of this study indicated the applicability of fixed-bed adsorber for removing remazol reactive yellow from solution. (C) 2008 Elsevier B.V. All rights reserved.

The death blow to unlimited liability in Victorian Britain: The City of Glasgow failure

In 1878, one of Britain's largest banks, the City of Glasgow Bank, collapsed, leaving a huge deficit between its assets and liabilities. As this bank, similar to many other contemporary British banks, had unlimited liability, its failure was accompanied by the bankruptcy of the vast majority of its stockholders. It is generally believed that the collapse of this depository institution revealed the extent to which ownership in large joint-stock banks had been diffused to investors of very modest means. It is also believed that the failure resulted in bank shareholders dumping their shares unto the market. Our evidence, garnered from ownership records, trading data, and stock prices, offers no support for these widely held beliefs. © 2007 Elsevier Inc. All rights reserved.

Complexity and Conundrums in Pollution Control:Improving Effectiveness in Regulatory Compliance

The last century has witnessed a dramatic increase in the wealth of European nations and the well being of their inhabitants. The focus has, however, largely been upon economic growth to the detriment of people and the environment. It is only in recent years that governments have taken cognisance of the impacts of our actions and there is a growing realisation that the causal factors must be identified and addressed as a matter of urgency. One of the key problem areas is pollution and as such environmental protection has become increasingly important as a mechanism for safeguarding the quality of air, water and land. This involves a range of activities from setting standards to monitoring and reporting on discharges and emissions, through to the enforcement of legislation. In theory, this is a simple challenge, in practice, it has proven to be an extremely complex equation that might only begin to be addressed through research. In this context it is strange, and alarming, to find that while it is an axiom of good practice that policy is informed by research there has been a dearth of investigation in this field. The purpose of this paper is, therefore, to consider the issue of pollution, how it impacts on the environment, what measures have been established in pursuit of reducing the number of incidences and, most significantly, which strategies might be employed to avoid or ameliorate detrimental impacts.