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To investigate the effect of laser densification parameters on the cross section geometry of the laser‐densified single line, and thus provide guidance for selecting the laser processing condition to obtain dense shapes with minimum processing defects.

A range of dental porcelain powder lines with small cross section areas (in the order of 1 × 1 mm²) were extruded from micro‐extruders and laser densified with the systematically changed peak laser power intensity, laser beam diameter, and ratio of the laser beam diameter to the width of the powder line.

The peak laser power intensity, laser beam diameter, and ratio of the laser beam diameter to the width of the powder line have substantial influence on the cross section geometry. The effects of these laser processing parameters can be explained in terms of minimization of surface energy in both solid and liquid states, volume shrinkage associated with densification, and temperature gradients present in the powder line during laser densification.

For the first time the cross section geometry of single powder lines in response to laser processing conditions has been systematically investigated, and the result offers guidance for obtaining dense shapes with minimum processing defects.

OUR new features of record and reminiscence appear to have been appreciated by our readers; and, as this number shows, we continue with increased pages and are endeavouring to extend our scope to meet every kind of library interest. There is an atmosphere, of change and, as some think, of crisis, in library matters, especially in those of the public library. The winter to which our minds turn in mid‐September is likely to be interesting and may bring decisions of various kinds. We hope to reflect them, and, as is our invariable custom, invite readers to use us to express their views as well as their experiences.

A three‐dimensional thermal finite element model including the effect of the powder‐to‐solid transition has been developed to investigate the transient temperature distribution and effects of substrate preheating during laser densification of dental powder bed for the layer‐by‐layer fabrication. The model encompasses the effects of the temperature‐ and porosity‐dependent thermal conduction and radiation as well as the temperature‐dependent natural convection. Substrate preheating is found to be important in preventing the formation of cracks in the dental porcelain body during laser densification. The simulation results are found to match the experiments very well.

A 3D finite element model was developed that simulates selective area laser deposition vapor infiltration (SALDVI) of silicon carbide. The model predicts the laser input power history needed to maintain constant surface temperature and the distribution of vapor deposited SiC within the powder bed as well as on the surface of the powder bed. The model considers a moving Gaussian distribution laser beam, temperature‐ and pore‐dependent thermal conductivity, specific heat and temperature‐dependent deposition rate. Furthermore, the model also includes closed‐loop control of the laser power to achieve a desired target processing temperature on the surface of the power bed. Effects of laser scanning rates have been investigated. The simulated solid fraction and SALD distributions are also consistent in the trend with the experimental data.

Commercial dental porcelain powder was deposited via slurry extrusion and laser densified to fabricate dental restorations in a multi‐material laser densification (MMLD) process.

A dental porcelain slurry was made from ball milled dental porcelain powders and extruded using the MMLD system. Extruded lines and rings were laser densified under different conditions in order to study how to build fully dense porcelain layers without warping and cracking during the MMLD process.

The geometric cross section of laser densified porcelain lines were dependent on laser processing parameters. Laser densified single ring showed no warping, and multiple layer body after laser densification showed cracks in the rings. The interface microstructure suggested good bonding between multiple layers. The mechanism to achieve single porcelain ring without warping and cracking is discussed. Alternate ways to build physical tooth layer by layer are proposed.

In the MMLD process, dental porcelain slurry was extruded from a human tooth computer file and laser densified to manufacture dental restorations based on solid freeform fabrication (SFF) principles. The understanding developed will pave the way for fabricating a physical dental restoration unit in the near future.

Residual thermal stresses and distortion are frequently present in the parts built using a layer‐by‐layer solid freeform fabrication techniques assisted with a moving laser source. This study uses finite element analysis to investigate the effect of laser scanning patterns on residual thermal stresses and distortion. It is shown that the out‐of‐plane distortion of a layer, processed by a moving laser beam can be minimized with a proper selection of the laser scanning pattern. A scanning pattern having changes in its scanning direction frequently by 90° at every turn can lead to the cancellation of concave upward and downward distortions. As a result of this cancellation, very small distortion is present in the laser processed plate. It is also found that distortion is mainly caused by transient thermal stresses rather than residual thermal stresses.

The purpose of this paper is to identify offender typologies based on aspects of the offenders’ psychopathology and their associations with crime scene behaviours using data derived from the National Confidential Enquiry into Suicide and Safety in Mental Health concerning homicides in England and Wales committed by offenders in contact with mental health services in the year preceding the offence (n=759).

The authors used multiple correspondence analysis to investigate the interrelationships between the variables and hierarchical agglomerative clustering to identify offender typologies. Variables describing: the offenders’ mental health histories; the offenders’ mental state at the time of offence; characteristics useful for police investigations; and patterns of crime scene behaviours were included.

Results showed differences in the offenders’ histories in relation to their crime scene behaviours. Further, analyses revealed three homicide typologies: externalising, psychosis and depression.

These typologies may assist the police during homicide investigations by: furthering their understanding of the crime or likely suspect; offering insights into crime patterns; provide advice as to what an offender’s offence behaviour might signify about his/her mental health background. Findings suggest information concerning offender psychopathology may be useful for offender profiling purposes in cases of homicide offenders with schizophrenia, depression and comorbid diagnosis of personality disorder and alcohol/drug dependence.

Empirical studies with an emphasis on offender profiling have almost exclusively focussed on the inference of offender demographic characteristics. This study provides a first step in the exploration of offender psychopathology and its integration to the multivariate analysis of offence information for the purposes of investigative profiling of homicide by identifying the dominant patterns of mental illness within homicidal behaviour.

OUR next number will contain our impressions and those of others of the Blackpool conference. Any anticipations made now will be obsolete by the middle of June. All that need be said here is that we hope no drastic change will have been suggested in the examination syllabus; all other matters are, in our view, legitimate matters for debate in general meetings, but where the syllabus is concerned only Fellows have the necessary qualifications to vote upon it. This we have expressed sufficiently perhaps in the past; there is, however, no harm in repeating it.

Research into the experience of BSc Psychology students and graduates in the graduate transition was carried out to enquire if ontology is central to educational transformation; if professional work experience is important in the process of becoming; and how graduates experience the transition from student to professional. The paper aims to discuss these issues.

In this qualitative longitudinal in-depth interview investigation four one-year work placement students were interviewed twice and five graduates were interviewed at graduation and again two years later. Student transcriptions were analysed thematically and graduate transcriptions received interpretative phenomenological analysis.

Placement students became legitimate participants in professional life. Graduates thought that BSc Psychology should enable a career and were dissatisfied when it did not. Professional psychology dominated career aspiration. Relationships and participation in work communities of practice were highly significant for learning, personal and professional identity and growth.

Ontology may be central to educational transformation in BSc Psychology and is facilitated by integrated work experience. A more vocational focus is also advocated.

The UK Bachelor’s degree in psychology is increasingly concerned with employability however becoming a professional requires acting and being as well as knowledge and skills and Barnett and others have called for higher education to embrace an ontological turn. This is explored in the context of BSc Psychology student experience and reflection on work placements, graduation and early career development.

Thisissue of Aslib Proceedings is mainly devoted to papers presented at the 24th Annual Conference, held at Ashorne Hill, near Learnington Spa, Warwickshire, from 9 to 11 September, 1949. In addition, we have pleasure in printing the annual report and accounts of the British Union Catalogue of Periodicals.