Modelling and Characterisation of the Texture Development in the Fusion Zone of An Austenitic Weld

The relation between texture and microstructure and the macroscopic solidification direction has been investigated for an austenitic 316L stainless steel weld. The fusion zone has been characterised by EBSD. Texture development has been simulated by thermal Finite Element Analysis coupled with a simple model of preferential <100>‐oriented solidification following the solidification direction. The thermal part is validated by means of thermocouple measurements at several locations on the specimen. The predicted texture is in very good agreement with the measured one.     

A study of the microstructural evolution during selective laser melting of Ti–6Al–4V

Selective laser melting (SLM) is an additive manufacturing technique in which functional, complex parts can be created directly by selectively melting layers of powder. This process is characterized by highly localized high heat inputs during very short interaction times and will therefore significantly affect the microstructure. In this research, the development of the microstructure of the Ti–6Al–4V alloy processed by SLM and the influence of the scanning parameters and scanning strategy on this microstructure are studied by light optical microscopy. The martensitic phase is present, and due to the occurrence of epitaxial growth, elongated grains emerge. The direction of these grains is directly related to the process parameters. At high heat inputs it was also found that the intermetallic phase Ti₃Al is precipitated during the process.     

The Dula Dangerous Driving Index: an investigation of reliability and validity across cultures

The aim of this study is to further establish the validity and reliability of the Dula Dangerous Driving Index (DDDI). The reliability and validity of the instrument was investigated by comparing data from a US university sample, a US community sample, and a sample of Belgian traffic offenders. Exploratory and confirmatory factor analysis supported the presence of a four-factor structure with items for Drunk Driving forming a separate scale apart from items for Risky Driving, Negative Cognitive/Emotional Driving and Aggressive Driving. A multi-group confirmatory factor analysis with model constraints supported the validity of the DDDI. Inter-correlations revealed that the DDDI subscales are closely interrelated and uni-dimensionality of the measure was found in all three samples. This suggests the DDDI Total score can be used as a composite measure for dangerous driving. However, the validity of the subscales was demonstrated in the Belgian sample, as specific traffic offender groups (convicted for drunk driving, aggressive driving, speeding) scored higher on corresponding scales (Drunk Driving, Aggressive Driving, and Risky Driving, respectively), indicating that it is clinically meaningful to differentiate the subscales.     

Experimental deformation analysis of an adhesively bonded multi-material joint for marine applications

The strength and deformation of full-scale adhesively bonded multi-material joints is studied in this paper. Four joints with a thick layer of methyl methacrylate adhesive (MMA) have been manufactured in shipyard conditions. In two specimens, cracks have been introduced at steel–adhesive and composite–adhesive interfaces. One cracked and one un-cracked specimen were subjected to quasi-static tensile testing; the two remaining specimens were stepwise loaded/unloaded with increasing load until failure. The strain in the adhesive layers was measured with digital image correlation (DIC). This showed a predominant shear deformation and dissimilar shear strain patterns for different bond lines. Fibre Bragg (FBG) sensors were used to monitor strains at steel and composite constituents and to detect the onset and evolution of damage in the un-cracked specimen. Strains measured by FBG sensors correspond well with DIC results at nearby regions. All specimens failed by delamination of the composite panel near the composite–adhesive interface.     

A Thermodynamic Model of the EAF Process for Stainless Steel

A time‐dependent thermochemical model has been developed for the electric arc furnace (EAF) process for stainless steel production. Time dependency is implemented by a stepwise input of energy and matter into an equilibrium reactor. The equilibrium calculations are performed using data from FACT‐databases and implemented using the programming library ChemApp. The material input for the model was generated by reconciliation of industrial data and the energy input is approximated from the industrial data and scaled through an efficiency factor. The model is used to calculate the evolution of temperature and composition of gas, slag and metal phases with time. Agreement of the end composition in the metal phase with industrial data is good. In the slag phase, however, Cr, Fe, Mn and Si are oxidized significantly less than expected due to excess formation of CO‐gas. The dynamics of the slag composition are examined in more detail. Here a fair agreement is reached for the main slag components. However, for Cr, Fe and Mn the model cannot predict the dynamics, which seem to be strongly kinetically controlled. The results of the equilibrium model can thus provide some insight into the kinetics of the process.     

Actual neurosis and PTSD: The impact of the other.

The authors argue that posttraumatic stress disorder (PTSD) is not an automatic consequence of a trauma. A review of empirical research demonstrates that there must be subjective mediating factors. On the basis of a conceptual reasoning, the existence of an actual-neurotic structure prior to the traumatic event is put forward as a precondition for the development of PTSD. Freud's theory on actual neurosis is interpreted as the impossibility to process the arousal coming from the drive in a symbolic way. The reason for this impossibility is sought in the failure of the primary caretakers in presenting the child with the necessary symbolic tools for drive regulation. The therapeutic implications of the presence of an actual-neurotic structure are important, because it can lead to a failure of free association. Suggestions for a more fruitful approach are formulated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intrauterine tracheal obstruction, a new treatment for congenital diaphragmatic hernia, decreases amniotic fluid sodium and chloride concentrations in the fetal lamb

The chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP) interacts with neutrophils, generating signals that induce activation of the superoxide anion/hydrogen peroxide-producing NADPH-oxidase. Low temperature binding of fMLP to its neutrophil surface receptors is associated with a desensitization of the cells with respect to activation of the oxidase. Other stimuli can still activate the oxidase (in fact even induce a primed response), indicating that the observed phenomenon is stimulus specific and could not be accounted for by an effect on the oxidase itself. Furthermore, no desensitization is obtained in the presence of cytochalasin B, suggesting that the cytoskeleton is involved in the process leading to desensitization. Okadaic acid is a toxin produced by dinoflagellates and exerts its effects by an inhibition of cellular phosphatases. To investigate the role of phosphorylation/dephosphorylation events in the desensitization process we used okadaic acid as a scientific tool. We show that neutrophils treated with okadaic acid are primed with respect to the fMLP-induced production of superoxide anion, and that no desensitization is obtained in toxin-treated cells. Because the recovery of ligand-receptor complexes in a Triton X-100-insoluble fraction is very low in the cells treated with okadaic acid, we suggest that protein dephosphorylation is required to obtain binding to the cytoskeleton of occupied fMLP receptors; binding of the occupied receptors to the cell cytoskeleton being the mechanism behind desensitization.     

Rt-PA thrombolysis in the treatment of massive pulmonary embolism

BACKGROUND: Research on psychiatric morbidity among patients with dermatological diseases generally focuses on outpatients and questionnaire-based surveys. The aim of this study was to determine the prevalence and nature of psychiatric morbidity among dermatological inpatients with diagnosis being made by psychiatric interview, and ascertain whether demographic and clinical details in dermatological inpatients with psychiatric morbidity differed from those without it. METHODS: Charts of all inpatients admitted by the dermatology department between 1 January 1991 and 31 July 1995 were analysed for socio-demographic data, clinical features, treatment and course in hospital. For those patients who were referred to a psychiatrist, all records of the psychiatric consultation were obtained and analysed. RESULTS: A total of 1073 patients were admitted during the study period. Ninety-eight patients (9%) were diagnosed to have a psychiatric illness. Patients with psychiatric illness were likely to have had more admissions and longer duration of hospital stay. The most common psychiatric diagnoses were depressive episodes (34%) and adjustment disorders (29%). The highest rates of psychiatric morbidity were found among patients with chronic urticaria, exfoliative dermatitis and sexually transmitted diseases, including human immunodeficiency virus infection. The prevalence of psychiatric disorders was significantly higher in those who had received long term (more than six weeks) treatment with high-dose steroids (more than 1 mg/kg body weight of prednisolone). CONCLUSION: Some dermatology inpatients have psychiatric morbidity, which affects the course of the dermatological condition as well as the duration of hospitalization. The availability of psychiatric consultation at dermatology clinics and regular liaison between psychiatrists and dermatologists are essential for appropriate management.