Murray James Barrett, dental anthropologist: Yuendumu and beyond.

Murray James Barrett (1916-1975) graduated from the University of Adelaide's Bachelor of Dental Surgery programme in 1939 and subsequently became a colleague of Professor Thomas Draper Campbell (1893-1967). Campbell's passion for dental anthropology and his special interest in food habits and dental disease inspired Barrett to commence a longitudinal growth study in the 1960s of Aboriginal Australians living at Yuendumu in the Northern Territory of Australia. This study, referred to as the Dentgro project, involved the collection of dental records, growth data and cultural information about the Wailbri people. Murray Barrett's application of computer technology enabled him to automate the entry of data derived from the Dentgro study and to develop programmes to analyse those data. The collection of dental casts (over 1700 serial casts for more than 450 individuals) and other records have provided a unique resource for research and teaching purposes. The casts have been in constant use for over 40 years providing insights into many aspects of dental development, including: the timing and sequence of tooth emergence; the nature and extent of variation in dental crown size and morphology in human populations; the patterns of growth in the dental arches over time; the range of occlusal variation between individuals; and the effects of wear on the dentition. The Yuendumu cast collection, representing a population with limited exposure to European customs and dietary habits, continues to attract the Adelaide School of Dentistry many interstate and overseas researchers interested in genetic and environmental influences on human dental development.

Containerless measurements of thermophysical properties of Zr54Ti8Cu20Al10Ni8.

High-temperature measurement and study of reactive materials can be difficult with conventional processing methods because contamination from the measuring apparatus and container walls can adversely affect measurements. Containerless processing techniques can be employed to isolate samples from their environment, reducing contamination. Benefits of containerless processing include reduction in heterogeneous nucleation sites, which in turn delays the onset of solidification and allows the study of meta-stable undercooled phases. However, property measurements must use noncontact methods as well. Fortunately, several optical-based methods have been developed and successfully employed to measure thermophysical properties, including surface tension, viscosity, density, and thermal expansion. Combining these techniques with the electrostatic levitator (ESL) located at the NASA Marshall Space Flight Center (MSFC) has resulted in an excellent facility to perform containerless material studies which support microgravity flight projects. Currently, studies of the thermophysical properties of liquid quasi-crystal forming and related alloys ranging from superheated to deeply undercooled states are being done with this facility in support of the NASA-funded flight project Quasi-crystalline Undercooled Alloys for Space Investigation (QUASI). While the primary purpose of these measurements is to support planned flight experiments, they are also a desirable resource for future manufacturing considerations and for fundamental insight in the physics of icosahedral ordering in liquids and solids. Presented here is an overview of the contactless measuring methods for surface tension, viscosity, density, and thermal expansion applied to Zr54Ti8Cu20Al10Ni8, for the superheated and meta-stable undercooled liquid phases, in support of QUASI.

In situ high-energy x-ray diffraction study of the local structure of supercooled liquid Si.

Employing the technique of electrostatic levitation, coupled with high-energy x-ray diffraction and rapid data acquisition methods, we have obtained high quality structural data more deeply into the supercooled regime of liquid silicon than has been possible before. No change in coordination number is observed in this temperature region, calling into question previous experimental claims of structural evidence for the existence of a liquid-liquid phase transition.

Difference in icosahedral short-range order in early and late transition metal liquids.

New short-range order data are presented for equilibrium and undercooled liquids of Ti and Ni. These were obtained from in situ synchrotron x-ray diffraction measurements of electrostatically levitated droplets. While the short-range order of liquid Ni is icosahedral, consistent with Frank's hypothesis, significantly distorted icosahedral order is observed in liquid Ti. This is the first experimental observation of distorted icosahedral short-range order in any liquid, although this has been predicted by theoretical studies on atomic clusters.

First x-ray scattering studies on electrostatically levitated metallic liquids: demonstrated influence of local icosahedral order on the nucleation barrier.

To explain the unusual stability of undercooled liquids against crystallization, Frank hypothesized that the local structures of undercooled liquids contain a significant degree of icosahedral short-range order, which is incompatible with long-range periodicity. We present here the first direct experimental demonstration of Frank's complete hypothesis, showing a correlation between the nucleation barrier and a growing icosahedral short-range order with decreasing temperature in a Ti39.5Zr39.5Ni21 liquid. A new experimental facility, BESL (Beamline Electrostatic Levitation), was developed to enable the synchrotron x-ray structural studies on deeply undercooled, reactive liquids.

EVI1 expression in acute myeloid leukaemia.

Acute myeloid leukaemia (AML) with 3q26 cytogenetic abnormalities is associated with overexpression of EVI1, dysmegakaryopoiesis and poor prognosis. Screening for EVI1 transcripts was performed in 336 cases of AML, including 139 patients with acute promyelocytic leukaemia (APL). Expression was detected in 7 out of 10 cases with and 23 out of 326 without 3q26 abnormalities including one APL case. Among cases lacking 3q abnormalities, detection of EVI1 transcripts was neither associated with characteristic dysmegakaryopoietic features, nor predictive of a poor outcome, indicating that screening will probably not assist in treatment stratification. This study nevertheless demonstrates that deregulation of EVI1, although rare in APL, is a relatively frequent event in AML.

Rational and assisted suicidal communication on the Internet: case example and discussion of ethical and practice issues.

The development of ethical and practice guidelines related to mental health service on the Internet has lagged behind the movement of practitioners into this area. Even for clinicians who are not offering services on the Web, the Internet has led to confusion and concern about proper roles and responsibilities. This article discusses an actual experience we had with a self-described rationally suicidal man with multiple sclerosis (MS). After presenting some background on MS, we report initial interactions with the man verbatim and summarize subsequent correspondence in an analysis of the man's claim that his decision to die was well reasoned and that he should be allowed a physician's assistance.

A study to determine whether trisomy 8, deleted 9q and trisomy 22 are markers of cryptic rearrangements of PML/RARalpha, AML1/ETO and CBFB/MYH11 respectively in acute myeloid leukaemia. MRC Adult Leukaemia Working Party. Medical Research Council.

Acute myeloid leukaemia (AML) patients with either a t(15;17), t(8;21) or inv(16) at diagnosis have 'good-risk' disease with a favourable response to therapy and improved survival. Detection of cryptic fusion genes created by these translocations has been reported where there is no cytogenetic evidence of the corresponding abnormality. It is likely that these cases share the same favourable prognosis. Secondary cytogenetic changes commonly associated with these rearrangements are +8 with t(15;17), del(9q) with t(8;21) and +22 with inv(16). These secondary abnormalities are also observed alone, raising the possibility that they may be markers of underlying cryptic rearrangements. In order to determine the frequency of these rearrangements in AML cases with +8, del(9q) or +22 we have performed an analysis of 63 such patients in whom there was no evidence of a t(15;17), t(8;21) or inv(16) by cytogenetics. No disease-related fusion transcripts were identified, indicating that the secondary changes are rarely markers for cryptic rearrangements.

Vision 21 Delphi panel: senior Army Medical Service Corps Officers' vision of behaviors for success of future Medical Service Corps officers.

A Delphi study was conducted of Army senior Medical Service Corps leaders (O6s) to identify the expected behaviors and competencies needed to ensure that junior officers will achieve successful careers as Medical Service Corps officers in the 21st century. A Delphi mailing was conducted in two phases. In the first iteration, 41 behaviors were identified to be of importance. In the second mailing, the 41 behaviors were rated for relative importance on a 7-point bipolar rating scale (1 = unimportant, 7 = most important). Comparisons were made between the ratings of administrative and biomedical scientific/technical (BS/T) series. Discriminant models developed to compare demographics between administrative and BS/T officers indicated that administrative officers had more time in grade, years of service, and professional military education, whereas BS/T officers reported significantly more civilian education. Minor differences among the two groups emerged for behavior ratings; however, the final priority order of behaviors reflected a high degree of consensus from both groups.

Incidence of AML1/ETO fusion transcripts in patients entered into the MRC AML trials. MRC Adult Leukaemia Working Party.

Acute myeloid leukaemia (AML) with the t(8;21)(q22;q22) is deemed to be a 'good-risk' disease. 396 patients with AML at diagnosis were screened for the presence of t(8;21) and AML1/ETO fusion transcripts by cytogenetic and RT-PCR techniques respectively. 32 cases of t(8;21) were detected, all of which were also PCR positive. A further 19 cases were detected at the molecular level, predominantly but not exclusively in M1 and M2 FAB types. Approximately 12% of all new cases of AML are estimated to have AML1/ETO fusion transcripts and it is suggested that molecular screening should be performed in all cases with the possible exception of the M3 FAB type.

Assessing right to die attitudes: a conceptually guided measurement model.

This article discusses the current status of research regarding the assessment of attitudes toward euthanasia and other right to die constructs with a focus on conceptual and methodological issues hindering advancement in this area. Two models are presented: a conceptual model for differentiating the various right to die constructs, and a measurement model to guide scale development and refinement. The conceptual model defines the right to die constructs as a function of locus of decision and locus of action. Health status and age are hypothesized as important factors that in some instances are defining attributes in right to die constructs and in other instances are factors influencing people's attitudes toward the right to die. The measurement model considers the importance of construct specificity, individual characteristics, and conviction in the assessment of right to die attributes. An extant euthanasia attitude scale is presented and evaluated in terms of the models to demonstrate how they may be useful for advancing attitude research in this important area.

Application of nitrogen from swine lagoon effluent to bermudagrass pastures: seasonal changes in forage nitrogenous constituents and effects of energy and escape protein supplementation on beef cattle performance.

A 2-yr study was conducted to evaluate 1) the effects of nitrogen level from swine lagoon effluent on forage composition and animal performance and 2) the effects of supplemental escape protein (EP) on performance by steers grazing pastures fertilized with swine lagoon effluent. Bermudagrass (Cynodon dactylon) pastures were fertilized via sprinkler irrigation with either 448 or 896 kg/ha of N from swine lagoon effluent (two pasture replications/treatment). Within each pasture, four supplement treatments were evaluated using electronic Calan gates (8 steers.pasture-1.yr-1). The treatments were 1) negative control (pasture only); 2) energy control, which supplied 79.9 g of EP.hd-1.d-1; 3) 159 g of EP.hd-1.d-1, and 4) 239 g of EP.hd-1.d-1. Gains were increased (P < .05) an average of .15 kg/d by supplementation, with no differences in gain among supplements. Forage samples representative of that grazed by steers (CONSUM) and representative of all available forage (AVAIL) were obtained at 14-d intervals. Total CP content of CONSUM and AVAIL samples were slightly higher (P < .20 and P < .15, respectively) from pastures fertilized with 896 compared with 448 kg/ha of N (20.8 vs 20.0% for CONSUM and 15.2 vs 14.2% for AVAIL). Concentrations of nonprotein N and soluble true protein (% of CP) in both AVAIL and CONSUM samples were higher (P < .06) from pastures fertilized with the higher N level. Total N uptake by the plant, based on CP content and animal grazing days/ha, was essentially the same for both N treatments.

Cross-validation of the five-factor interpretive model of the Suicide Opinion Questionnaire.

This study is a cross-validation analysis of the five-factor interpretative model of the Suicide Opinion Questionnaire (Domino, Moore, Westlake, & Gibson, 1982) reported by Rogers and DeShon (1992). Results indicated moderate support for the five-factor model. That is, although the factor analysis results generally supported the 5-factor model, a number of items loaded equally well across 2 or more factors. Additionally, internal consistency and test-retest reliabilities ranged from .48 to .85 and from .34 to .92, respectively, indicating weaknesses in some of the subscales. Strategies are suggested for the future psychometric development and refinement of the instrument.

Assessing the "modeling effect" in parasuicidal behavior: a comment on Platt (1993)

This article provides a critical evaluation of Platt's [1993] research investigating the role of modeling in the acquisition of parasuicidal behavior. The discussion focuses on general theoretical and methodological issues related to research in this area, as well as on specific concerns regarding Platt's investigation. In addition to presenting a critique of this research, a hypothetical model is presented that should lend credibility to future investigations into the theoretically posited casual relationships within the modeling paradigm. Model selection was based upon a recognition that an adequate test of the observational learning theory would need to appropriately employ correlational data commonly found in research in suicide and parasuicide. The implications for clinical practice are presented.

A reliability investigation of the eight clinical scales of the Suicide Opinion Questionnaire.

The Suicide Opinion Questionnaire (SOQ) has been employed in a variety of settings as a measure of attitudes toward suicidal behavior. However there has been a lack of consensus across these studies with regard to the underlying factor structure of the measure. In addition there has been little empirical information reported in the literature regarding the scale's reliability. This article presents a psychometric investigation of the 8-factor clinical model of the SOQ as representing the most appropriate interpretive model for the SOQ. Factor-analytic and internal consistency reliability results failed to support the hypothesized 8-factor model. An alternative factor scheme and suggestions for future research on the SOQ are discussed.

Interferometric measurement of group and phase refractive index.

An experimental apparatus has been designed to measure group refractive index (n(g)) by observing the shift of the fringe visibility envelope upon insertion of a sample into one arm of a Twyman-Green interferometer. A criterion is developed for the limiting bandwidth and thickness for which good visibility may be expected and for predicting the bandwidth for the narrowest visibility curve. It is demonstrated that the measured group index data can be converted to phase index data with a previously described technique [J. R. Rogers and M. D. Hopler, J. Opt. Soc. Am. A 5, 1595-1600 (1988)] to an accuracy of approximately 0.0006 across the visible spectrum.

End-stage renal failure in children: 16 years' experience at one Australian centre.

Sixty-five children over one year and under 15 years of age began treatment for end-stage renal failure between 1973 and 1988. Sixty-one renal transplants were performed in 53 children, 39 of these were from living donors (38 were first-degree relatives and one was an emotionally related volunteer). Thirteen children, of whom seven had received transplants and six had not, died, including three children with functioning transplants; nine deaths occurred in the first eight years of the programme. Cumulative five-year and 10-year patient survival rates were 78% and 75%, respectively. Eighteen transplants failed, 12 as a result of rejection, five as a result of disease recurrence and one due to primary non-function. Cumulative five-year and 10-year transplant survival rates for first grafts were 66% and 53%, respectively. For living donor transplants these rates were 85% and 68%, respectively. Growth rates fell by 0.4 +/- 0.05 standard deviation score (SDS) per year in children undergoing dialysis, were normal in children with renal transplants receiving prednisone (change in SDS per year, -0.02 +/- 0.08) and increased by 0.36 +/- 0.07 SDS per year in children with transplants receiving cyclosporin A alone. Currently, 32 (82%) of 39 transplant recipients and 7 (58%) of 12 patients undergoing dialysis attend school or work full time. Although both dialysis and transplantation are acceptable therapies for children with end-stage renal failure, successful transplantation provides the best opportunity for satisfactory growth and development.

Optical performance of holographic kinoforms.

The optical properties of holographic kinoforms are described. It is shown that paraxial designs are not adequate for f/Nos. less than F/10. A nonparaxial design is introduced that retains the high diffraction efficiency of the paraxial designs, yet also produces an unaberrated diffracted wavefront for the design wavelength. Aberration calculations and computer calculations, based on the Huygens-Fresnel principle, of the point spread functions for these elements show the necessity of using the nonparaxial design. Specifications for a surface profile that takes account of the finite thickness of the diffracting surface are given. A model for kinoforms which can be used in optical design programs is proposed.