Adsorption of flexible n-alkane on graphitized thermal carbon black: analysis of adsorption isotherm by means of GCMC simulation

In this paper, we investigate the suitability of the grand canonical Monte Carlo in the description of adsorption equilibria of flexible n-alkane (butane, pentane and hexane) on graphitized thermal carbon black. Potential model of n-alkane of Martin and Siepmann (J. Phys. Chem. 102 (1998) 2569) is employed in the simulation, and we consider the flexibility of molecule in the simulation. By this we study two models, one is the fully flexible molecular model in which n-alkane is subject to bending and torsion, while the other is the rigid molecular model in which all carbon atoms reside on the same plane. It is found that (i) the adsorption isotherm results of these two models are close to each other, suggesting that n-alkane model behaves mostly as rigid molecules with respect to adsorption although the isotherm for longer chain n-hexane is better described by the flexible molecular model (ii) the isotherms agree very well with the experimental data at least up to two layers on the surface.

A study on transition of iron from active into passive state

An investigation was carried out on the transition of an iron electrode from active to passive state in a sulphuric acid solution. It was found that the active-passive transition was an auto-catalytic process in which a pre-passive film grew on the electrode surface. The growing pre-passive film had a fractal edge whose dimension was affected by the applied passivating potential and the presence of chlorides in the solution. Applying a more positive passivating potential led to a faster active-passive transition and resulted in a more irregular pre-passive film. If chlorides were introduced into the sulphuric acid solution, the active-passive transition became more rapid and the pre-passive film more irregular. Apart from the influence on the growth of the pre-passive film, the presence of chlorides in the passivating solution was found to deteriorate the stability of the final passive film. All these phenomena can be understood if the passivating iron electrode is regarded as a dissipative system. To explain these results, a fractal pre-film model is proposed in this paper. (C) 2004 Elsevier Ltd. All rights reserved.

Optofluidics enables compact tunable interferometer

An optofluidic interferometer - in which a beam propagates across an interface between fluid and air - modulates at high extinction ratios and is only microns in size.

An inflammatory role for the mammalian carboxypeptidase inhibitor latexin: Relationship to cystatins and the tumor suppressor TIG1

Latexin, the only known mammalian carboxypeptidase inhibitor, has no detectable sequence similarity with plant and parasite inhibitors, but it is related to a human putative tumor suppressor protein, TIG1. Latexin is expressed in the developing brain, and we find that it plays a role in inflammation, as it is expressed at high levels and is inducible in macrophages in concert with other protease inhibitors and potential protease targets. The crystal structure of mouse latexin, solved at 1.83 Angstrom resolution, shows no structural relationship with other carboxypeptidase inhibitors. Furthermore, despite a lack of detectable sequence duplication, the structure incorporates two topologically analogous domains related by pseudo two-fold symmetry. Surprisingly, these domains share a cystatin fold architecture found in proteins that inhibit cysteine proteases, suggesting an evolutionary and possibly functional relationship. The structure of the tumor suppressor protein TIG1 was modeled, revealing its putative membrane binding surface.

Corrosion of magnesium alloys in commercial engine coolants

A number of magnesium alloys show promise as engine block materials. However, a critical issue for the automotive industry is corrosion of the engine block by the coolant and this could limit the use of magnesium engine blocks. This work assesses the corrosion performance of conventional magnesium alloy AZ91D and a recently developed engine block magnesium alloy AM-SC1 in several commercial coolants. Immersion testing, hydrogen evolution measurement, galvanic current monitoring and the standard ASTM D1384 test were employed to reveal the corrosion performance of the magnesium alloys subjected to the coolants. The results show that the tested commercial coolants are corrosive to the magnesium alloys in terms of general and galvanic corrosion. The two magnesium alloys exhibited slightly different corrosion resistance to the coolants with AZ91D being more corrosion resistant than AM-SC1. The corrosivity varied from coolant to coolant. Generally speaking. an oraganic-acid based long life coolant was less corrosive to the magnesium alloys than a traditional coolant. Among the studied commercial coolants. Toyota long, life coolant appeared to be the most promising one. In addition. it was found that potassium fluoride effectively inhibited corrosion of the magnesium alloys in the studied commercial coolants. Both general and galvanic corrosion rates were significantly decreased by addition of KF, and there were no evident side effects on the other engine block materials, such as copper, solder. brass. steel and aluminium alloys, in terms of their corrosion performance. The ASTM D 1384 test further confirmed these results and suggested that Toyota long life coolant with 1%wt KF addition is a promising coolant for magnesium engine blocks.

Integrated versus non-integrated management and care for clients with co-occurring mental health and substance use disorders: a qualitative systematic review of randomised controlled trials

The purpose of this paper is to conduct a qualitative review of randomised controlled trials in relation to the treatment of adults with co-occurring mental health and substance use disorder (MH/SUD). In particular, integrated approaches are compared with non-integrated approaches to treatment. Ten articles were identified for inclusion in the review. The findings are equivocal with regard to the superior efficacy of integrated approaches to treatment, although the many limitations of the studies need to be considered in our understanding of this finding. Clearly, this is an extremely challenging client group to engage and maintain in intervention research, and the complexity and variability of the problems render control particularly difficult. The lack of available evidence to support the superiority of integration is discussed in relation to these challenges. Much remains to be investigated with regard to integrated management and care for people with co-occurring and MH/SUD, particularly for specific combinations of dual diagnosis and giving consideration to the level of inter-relatedness between the disorders. (C) 2004 Elsevier Ltd. All rights reserved.

Accumulation and toxicity of monophenyl arsenicals in rat endothelial cells

Clark 1 (diphenylarsine chloride) and Clark 2 ( diphenylarsine cyanide) were used as chemical weapon agents (CWA), and the soil contamination by these CWA and their degraded products, diphenyl and phenyl arsenicals, has been one of the most serious environmental issues. In a series of comparisons in toxicity between trivalent and pentavalent arsenicals we investigated differences in the accumulation and toxicity of phenylarsine oxide (PAO(3+)) and phenylarsonic acid (PAA(5+)) in rat heart microvascular endothelial cells. Both the cellular association and toxicity of PAO(3+) were much higher than those of PAA(5+), and LC50 values of PAO(3+) and PAA(5+) were calculated to be 0.295 muM and 1.93 mM, respectively. Buthionine sulfoximine, a glutathione depleter, enhanced the cytotoxicity of both PAO(3+) and PAA(5+). N-Acetyl-L-cysteine (NAC) reduced the cytotoxicity and induction of heme oxygenase-1 (HO-1) mRNA in PAO(3+)-exposed cells, while NAC affected neither the cytotoxicity nor the HO-1 mRNA level in PAA(5+)-exposed cells. The effect of NAC may be due to a strong affinity of PAO(3+) to thiol groups because both NAC and GSH inhibited the cellular accumulation of PAO(3+), but PAA(3+) increased tyrosine phosphorylation levels of cellular proteins. These results indicate that the inhibition of protein phosphatases as well as the high affinity to cellular components may confer PAO(3+) the high toxicity.

The combined SPE : ToxY-PAM phytotoxicity assay; application and appraisal of a novel biomonitoring tool for the aquatic environment

Mounting concerns regarding the environmental impact of herbicides has meant a growing requirement for accurate, timely information regarding herbicide residue contamination of, in particular, aquatic systems. Conventional methods of detection remain limited in terms of practicality due to high costs of operation and the specialised information that analysis provides. A new phytotoxicity bioassay was trialled for the detection of herbicide residues in filter-purified (Milli-Q) as well as natural waters. The performance of the system, which combines solid-phase extraction (SPE) with the ToxY-PAM dual-channel yield analyser (Heinz Walz GmbH), was tested alongside the traditional method of liquid chromatography-mass spectrometry (LC-MS). The assay methodology was found to be highly sensitive (LOD 0.1 ng L-1 diuron) with good reproducibility. The study showed that the assay protocol is time effective and can be employed for the aquatic screening of herbicide residues in purified as well as natural waters.

Sexual abuse in childhood and sexual dysfunction in adulthood: An Australian population-based study

This study examined self-reported adult sexual functioning in individuals reporting a history of childhood sexual abuse (CSA) in a representative sample of the Australian population. A sample of 1793 persons, aged 18-59 years, were randomly selected from the electoral roll for Australian states and territories in April 2000. Respondents were interviewed about their health status and sexual experiences, including unwanted sexual experiences before the age of 16 years. More than one-third of women and approximately one-sixth of men reported a history of CSA. Women were more likely than men to report both non-penetrative and penetrative experiences of CSA. For both sexes, there was a significant association between CSA and symptoms of sexual dysfunction. In assessing the specific nature of the relationship between sexual abuse and sexual dysfunction, statistically significant associations were, in general, evident for women only. CSA was not associated with the level of physical or emotional satisfaction respondents experienced with their sexual activity. The total number of lifetime sexual partners was significantly and positively associated with CSA for females, but not for males; however, the number of sexual partners in the last year was not related to CSA. CSA in the Australian population is common and contributes to significant impairment in the sexual functioning of adults, especially women. These consequences appear not to extend to the other areas of sexual activity considered in this study.

Faith and politics: The rhetoric of church-state separation

Criticism of religiously motivated contributions to public policy debate is largely misconceived. It assumes that the mischief which constitutional separation of church and state is supposed to cure is a domination of the state by the church. This presents only one side of the story. Subservience by the church to the slate should also be avoided. The law of a liberal state is legitimate to the extent that it does not conflict with the basic moral values of its citizens. Therefore, an ongoing conversation about basic values is necessary. Allowing churches and individual believers the freedom to make distinctive 'religious' contributions to this conversation is consistent with the separation of church and state. It is an aspect of the liberal democratic state's obligation to listen to all perspectives on difficult moral issues. A close relationship between church and state, on the other hand, has the capacity to impede the conversation.

Transnational organised crime and the International Criminal Court developments and debates

Limitation to jurisdiction of International Criminal Court (ICC) - proposal to strengthen the universal criminalisation of transnational organised crimes by enabling them to be prosecuted through an international authority - debate on whether existing offences under the ICC Statute encompass certain transnational organised crimes - whether the Statute should be expanded to include crimes that have been recognised in international treaties.

Unconscionability and commercial law

Standard of unconscionability in private and commercial cases - argument for caution in the standard's use - instability as a juridical notion - concern about the coherence of the doctrine - statutory provisions in Australia compound current problems - questionable status of unconscionability as a legally useful term.