Approximation of ill-posed boussinesq equations

In this paper we compare the dynamics on the centre manifold of the solutions of an ill-posed Boussinesq equation with a well-posed version. We show that the dynamics in the centre manifold of the ill-posed equation tracks the dynamics of the well-posed equation. Our results give partial justification to the long-wave perturbation theory.     

A formal description of open distributed processing (ODP) trading based on guidelines for the definition of managed objects (GDMO)

New requirements of growing computer networks and information systems have an influence on extended client/server models with increased functionality. This forms the basis for service management in distributed systems which is realized by a service trading concept. This paper studies the requirements derived from the Open Distributed Processing (ODP) Reference Model in order to consider an open service market. Furthermore, it examines management possibilities for describing the service trading scenario. Because of similar architectures and properties ODP services, service offers, types, exporters and traders are mapped onto management components and modeled as managed objects. Therefore, the Guidelines for the Definition of Managed Objects (GDMO) are used. The final concept allows a precise and unambiguous study of the service trading scenario and provides means for exporting and importing of service offers in a distributed environment.     

Vom freiwilligen Seminar zur Q2-Pflichtveranstaltung

Definition of the problem: Ethical reasoning cannot be enforced. Voluntary understanding is a basic condition for the development of ethical competencies and attitudes. The aim of this survey was to investigate whether the presence of those students who attended our seminars compulsorily would have a negative effect upon the quality of the course. Methods and results: The participants of our small-group seminars in medical ethics were asked to complete a questionnaire on teaching aims, seminar atmosphere, moderation and importance of subjects. One hundred and ninety-two voluntary participants (2001/2) and 293 compulsory participants (2002/3) completed the questionnaire and were statistically compared. There was no significant difference between voluntary and compulsory participants in any of the important items. However, there were considerable differences in some items between male and female participants. Conclusion: We were surprised that there was no difference between the two groups. This leads us to hope that our concept of case-based small-group seminars will prove capable of realising our teaching aims for all students. The difference between male and female participants may have important didactic consequences and will be the subject of further studies.     

Crystallization of some anorthite-diopside glass precursors

Anorthite and diopside have been obtained from complete devitrification of glasses belonging to the quaternary system MgO-CaO-Al₂O₃-SiO₂. Microstructure, the natural trend of the nucleation mechanism and kinetic studies on the crystallization phenomenon have been investigated by means of optical and electron microscopies, thermal and thermomechanical techniques and X-ray powder diffractometry. All the glasses investigated show a complete crystallization starting from a simple surface nucleation process. The activation energy for the crystallization process proved to be higher than that for viscous flow, leading to an important aspect modification in the sample during ceramization. Thermal stability and physical properties of both glass and glass-ceramic materials have been tested, suggesting the possible use of these materials in industrial application.     

Specific interactions in blends containing Chitosan and functionalized polymers. Molecular dynamics simulations

Chitosan (CS)/poly(vinyl alcohol) (PVA) and Chitosan/poly(2-hydroxyethyl methacrylate) (P2HEM) blends have been studied through molecular dynamic simulations. In a previous work it was found miscibility between these polymers and it was attributed to hydrogen bonding formation. However, the experimental information obtained was not enough to know which of the interacting groups of Chitosan, i.e. -CH₂OH or -NH₂, are responsible of the interaction. Therefore, we have performed molecular dynamics simulation runs of 1 ns in order to calculate radial distribution functions (RDF) for the groups tentatively involved in the interaction. The results are correlated with our previous experimental data. This way, we have obtained a more precise conclusive information about the interactions involved as function of the blends composition. For low compositions of PVA and P2HEM the interaction is predominantly with the hydroxymethyl groups of CS while as the composition of PVA and P2HEM increases, the interaction with the amine groups increases.     

To treat or not to treat: comparison of different criteria used to determine whether weight loss is to be recommended

Background  

Excess body fat is a major risk factor for disease primarily due to its endocrine activity. In recent years several criteria have been introduced to evaluate this factor. Nevertheless, treatment need is currently assessed only on the basis of an individual's Body Mass Index (BMI), calculated as body weight (in kg) divided by height in m². The aim of our study was to determine whether application of the BMI, compared to adiposity-based criteria, results in underestimation of the number of subjects needing lifestyle intervention.     

The Impact of eBusiness and the Information Society on ‘STRATEGY’ and ‘STRATEGIC PLANNING’: An Assessment of New Concepts and Challenges

The current era of Information, Communication and Media Technologies (ICMT) has ushered in the era of eBusiness and the Information Society where traditional managerial paradigms are challenged and new business models are sought. One central area of managerial discourse is STRATEGY. Based upon a pilot study with leading European managers, consultants and academics, we offer a structured perspective on what may be the shape of things to come for STRATEGIC PLANNING in the context of eBusiness and the Information Society. Normative implications are explored.     

Comorbidity of drug dependence and other mental disorders: a two-phase study of prevalence at outpatient treatment centres in Italy

The proposed mechanism of action of the antineoplastic drug 3-nitrobenzothiazolo[3,2-alpha]quinolinium chloride (NBQ-2) involves its interaction with DNA by intercalation and inhibition of topoisomerase II activity by arresting the enzyme in a covalent cleavage complex. In an attempt to identify some structural determinants for activity and develop a molecular structure/cytotoxicity correlation, four new structural analogs of the antitumor NBQ-2 were prepared and their cytotoxic activity and DNA binding properties were investigated. The cytotoxic activity was evaluated against six different human tumor cell lines: U937, K-562, HL-60, HT-29, HeLa, and A431. The results showed that these new drugs elicit pronounced cytotoxic effects against U937, K-562, HL-60 and A431 while HeLa and HT-29 were less sensitive to the new drugs. This apparent selectivity was different to that of m-AMSA, a drug currently used for cancer treatment. Since the interaction of NBQ-2 to DNA by intercalation has been proposed as the initial step leading to its antineoplastic activity, DNA binding and changes in DNA contour length induced by the new NBQ-2 structural analogs were also investigated using calf thymus and human DNA. The drug, 7-(1-propenyl)-3-nitrobenzimidazolo[3,2-alpha]quinolinium chloride (NBQ-59) was the most cytotoxic agent of the analog series (IC50 = 16 microM for HL-60 cells), however, it demonstrated the weakest binding to DNA (Kint = 0.9 x 10[5] M-1 for calf thymus DNA). NBQ-59 was also found to be a poor intercalator into the DNA double helix. Therefore, our results suggest that DNA binding is not the primary mechanism of drug action for this family of compounds. In addition structural determinants important for cytotoxicity of the benzazolo quinolinium chlorides were suggested by our results. In particular, the nitro group in the 3 position does not seem to be necessary for bioactivity, while substitutions in the benzazolo moiety have striking effects on the biological activity of the drugs.     

Postoperative enteral feeding does not prevent intestinal bacterial translocation, but reduces the rate of pulmonary infections in pigs undergoing total orthotopic small bowel transplantation

OBJECTIVE: To assess the effects of a non-elemental liquid diet on nutritional state, composition of bowel flora, intestinal translocation, and pulmonary infections after small bowel transplantation in pigs. DESIGN: Prospective randomised experiment. SETTING: Teaching hospital, Italy. MATERIAL: 32 female Large White pigs. INTERVENTIONS: Group 1 (n = 6) underwent small bowel transplantation, were treated with immunosuppression, and fed on commercial chow. Group 2 (n = 6) were treated similarly except that they were fed with an enteral feed through a tube gastrostomy starting on day 4 postoperatively. Group 3 (n = 6) were treated similarly to group 1 except that they had no immunosuppression, and Group 4 (n = 6) underwent orthotopic small bowel autotransplantation; 8 further pigs underwent a sham operation only to act as controls. MAIN OUTCOME MEASURES: Signs of rejection, graft-versus-host-disease, luminal bacterial overgrowth, bacterial translocation, pneumonia, and the pigs' nutritional state. RESULTS: All animals in group 3 showed signs of acute rejection. There was appreciable overgrowth of aerobic and anaerobic bacteria in all three groups after allotransplantation compared with controls. The counts of anaerobic bacteria were significantly lower in group 2 (enterally fed animals) compared with those given free access to commercial chow [mean (SD) 2.81 (1.39) log CFU/cm2 compared with 4.80 (1.65), p = 0.047]. Bacterial translocation developed to a similar degree after autografts and allografts and pneumonia developed in fewer animals after enteral feeding (1/6) than after conventional feeding (5/6) but the difference was not significant (p = 0.08, odds ratio 25.0, 95% confidence interval of odds ratio 1.20 to 521.13). Enterally fed animals also lost less weight than conventionally fed animals [2.32 (1.23) kg compared with 4.53 (1.74), p = 0.016]. CONCLUSIONS: Enteral feeding for up to a month slightly reduced the rate of pneumonia and resulted in a better nutritional state in pigs after small bowel transplantation. It had no effect on luminal bacterial overgrowth or translocation.     

Data collection: evaluation of a pilot model

The overall purpose of this study was to explore nurses' feelings about the applicability and adequacy of a pilot model of nursing assessment (PMNA) developed for coronary care units (CCU) in order to obtain data that could help in establishing a definitive model. The evaluation, performed by 11 CCU nurses, showed that they considered the development and implementation of PMNA as valuable, and that its design was adequate for interviewing cardiac patients. These results will be employed in the elaboration of a definitive model of nursing assessment.