Comparison of nitrogen adsorption at 77 K on non-porous silica and pore wall of MCM-41 materials by means of density functional theory

Nitrogen adsorption on a surface of a non-porous reference material is widely used in the characterization. Traditionally, the enhancement of solid-fluid potential in a porous solid is accounted for by incorporating the surface curvature into the solid-fluid Potential of the flat reference surface. However, this calculation procedure has not been justified experimentally. In this paper, we derive the solid-fluid potential of mesoporous MCM-41 solid by using solely the adsorption isotherm of that solid. This solid-fluid potential is then compared with that of the non-porous reference surface. In derivation of the solid-fluid potential for both reference surface and mesoporous MCM-41 silica (diameter ranging front 3 to 6.5 nm) we employ the nonlocal density functional theory developed for amorphous solids. It is found that, to out, surprise, the solid-fluid potential of a porous solid is practically the same as that for the reference surface, indicating that there is no enhancement due to Surface curvature. This requires further investigations to explain this unusual departure from our conventional wisdom of curvature-induced enhancement. Accepting the curvature-independent solid-fluid potential derived from the non-porous reference surface, we analyze the hysteresis features of a series of MCM-41 samples. (c) 2005 Elsevier Inc. All rights reserved.

Dietary patterns and metabolic syndrome - a review of epidemiologic evidence

Metabolic syndrome is associated with increased risk of coronary heart disease and type 2 diabetes, and appears to be widely prevalent in both developed and developing countries. While lifestyle modification is recommended for management of the syndrome, the dietary pattern most beneficial for patients is yet to be ascertained. Original research papers from the Medline database were examined for dietary patterns that may be associated with the syndrome. Three large-scale epidemiological studies were found fitting our criteria. Dietary patterns high in fruit and vegetable content were generally found to be associated with lower prevalence of metabolic syndrome. Diet patterns with high meat intake were frequently associated with components of metabolic syndrome, particularly impaired glucose tolerance. High dairy intake was generally associated with reduced risk for components of metabolic syndrome with some inconsistency in the literature regarding risk of obesity. Minimally processed cereals appeared to be associated with decreased risk of metabolic syndrome, while highly processed cereals with high glycaemic index are associated with higher risk. Fried foods were noticeably absent from any dietary pattern associated with decreased prevalence of metabolic syndrome. The conclusion of this review is that no individual dietary component could be considered wholly responsible for the association of diet with metabolic syndrome. Rather it is the overall quality of the diet that appears to offer protection against lifestyle disease such as metabolic syndrome. Further research is required into conditions, such as overweight and obesity, which may influence the effect of diet on the development of metabolic syndrome.

Morphology of breast cancer as a means of triage of patients for BRCA1 genetic testing

Background: Women who have germline mutations in the BRCA1 gene are at substantially increased lifetime risk of developing breast and ovarian cancer but are otherwise normal. Currently. early age of onset of cancer and a strong family history are relied upon as the chief clues as to who should be offered genetic testing. Certain morphologic and immunohistochemical features are overrepresented in BRCA1-associated breast cancers but these differences have not been incorporated into the current selection criteria for genetic testing. Design: Each of the 4 pathologists studied 30 known cases of BRCA1- and BRCA2-associated breast cancer from kConFab families. After reviewing the literature, we agreed on a semiquantitative scoring system for estimating the chances of presence of an underlying BRCA1 mutation, based on the number of the reported prototypic features present. After a time lag of 12 months, we each examined a series of 62 deidentified cases of breast cancer, inclusive of cases of BRCA1-associated breast cancer and controls. The controls included cases of BRCA2-associated breast cancer and sporadic cases. Results: Our predictions had a sensitivity of 92%, specificity of 86%, positive predictive value of 61%, and negative predictive value of 98%. For comparison the sensitivity of currently used selection criteria are in the range of 25% to 30%. Conclusion: The inclusion of morphologic and immunohistochemical features of breast cancers in algorithms to predict the likelihood of presence of germline mutations in the BRCA1 gene improves the accuracy of the selection process.

What are the policy implications of the evidence on cannabis and psychosis?

Objective: To explore the implications for mental health services, for health education about the risks of cannabis use, and for public policy toward cannabis use of observational evidence that cannabis use is a contributory cause of psychosis. Method: Using comparative analyses of similar evidence for the harmful effects of alcohol, tobacco, and amphetamine use, we considered the relation between observational evidence and action on cannabis. We examined arguments on the grounds of public health prudence for discouraging cannabis use by young individuals. With the assumption that the relation may be causal, we considered recommendations for policy in mental health services, health education, and public policy toward cannabis. Results: The observational evidence and biological plausibility of the hypothesis that cannabis is a contributory cause of psychosis is at least as strong as evidence for causal relations between heavy alcohol and amphetamine use and psychosis. On public health grounds, there is a good case for discouraging cannabis use among adolescents and young adults. It remains uncertain how best to discourage use and at whom campaigns to reduce cannabis use should be targeted. Conclusions: We should discourage young adults seeking treatment in mental health services from using cannabis and inform them of the probable mental health risks of cannabis use, especially of early and frequent use. We must exercise caution in liberalizing cannabis laws in ways that may increase young individuals' access to cannabis, decrease their age of first use, or increase their frequency of cannabis use. We should consider the feasibility of reducing the availability of high-potency cannabis products.

Attenuated total reflection-FT-IR spectroscopic imaging of protein crystallization

Protein crystallization is of strategic and commercial relevance in the post-genomic era because of its pivotal role in structural proteomics projects. Although protein structures are crucial for understanding the function of proteins and to the success of rational drug design and other biotechnology applications, obtaining high quality crystals is a major bottleneck to progress. The major means of obtaining crystals is by massive-scale screening of a target protein solution with numerous crystallizing agents. However, when crystals appear in these screens, one cannot easily know if they are crystals of protein, salt, or any other molecule that happens to be present in the trials. We present here a method based on Attenuated Total Reflection (ATR)-FT-IR imaging that reliably identifies protein crystals through a combination of chemical specificity and the visualizing capability of this approach, thus solving a major hurdle in protein crystallization. ATR-FT-IR imaging was successfully applied to study the crystallization of thaumatin and lysozyme in a high-throughput manner, simultaneously from six different solutions. This approach is fast as it studies protein crystallization in situ and provides an opportunity to examine many different samples under a range of conditions.

FDI and the labour market: a review of the evidence and policy implications

This paper presents a series of results concerning the labour-market impact of inward foreign direct investment (FDI) in the UK. The paper demonstrates that one of the crucial impacts of FDI is to increase wage inequality and the use of relatively more skilled labour in the domestic firms. This result is found to be a combination of two effects. First, the entry by a multinational enterprise (MNE) increases the demand for skilled workers in an industry or region, thus increasing wage inequality. Second, technology spillovers occur from foreign to domestic firms. As a result of these spillovers, relative demand for skilled workers increases in the domestic firms, further contributing to aggregate wage inequality and skill upgrading. The paper also considers how FDI impacts upon skill shares by productivity differentials between foreign and domestic firms. Finally, the policy implications of this are discussed, from the perspective of regional development, and the likely effectiveness of attracting FDI to reduce structural unemployment.

What are the practical implications for treating diabetes in light of recent evidence? Updated recommendations from the Global Partnership for Effective Diabetes Management

The Global Partnership for Effective Diabetes Management was established in 2004 to provide practical guidance to improving glycaemic control for people with type 2 diabetes. Those recommendations have been updated to take account of recent trials assessing the effects of intensive glucose control. We continue to emphasis the importance of early and sustained glycaemic control, aiming for HbA( 1c) 6.5-7% wherever safe and appropriate. Individualisation of targets and the management process is strongly encouraged to accommodate patient circumstances and to avoid hypoglycaemia. Prompt introduction of combinations of agents is suggested when monotherapy is inadequate.Treatments will preferably address the underlying pathophysiology of type 2 diabetes and integrate within a wider programme of care which also aims to reduce modifiable cardiovascular risk factors and better equip patients in the self-management of their condition.

Wage inequality and the role of multinationals:evidence from UK panel data

Despite the increased attention on the impacts of globalisation, there has been little empirical investigation into the impact of multinational firms on the domestic labour market and in particular wage inequality, this is in spite of a rapid increase in foreign direct investment (FDI) at around the same time of rising inequality. Using UK panel data, this paper tests whether inward flows of FDI have contributed to increasing wage inequality. Even after controlling for the two most common explanations of wage inequality, technology and trade, we find that FDI has a significant effect upon wage inequality, with the overall impact of FDI explaining on average 11% of wage inequality. © 2003 Elsevier B.V. All rights reserved.