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We present a dynamic random access memory (DRAM) design technology co-optimization (DTCO) methodology that allows the optimization of the DRAM cell structure in the presence of contact resistance variation, trap-assisted tunneling (TAT) leakage variation, and storage node capacitance variation. We showcase our methodology features and results by studying the optimization of a DRAM metal gate work function under the constraints of writeability, retention time (tRET) performance, and robustness to the row hammer effect. Our simulation results show that DRAM performance and its reliability are strongly affected by the contact resistance variations induced by random discrete dopants (RDDs) and can be maximized by means of DTCO-based engineering of contact area and doping concentrations. Our findings also highlight that focusing the optimization on leakage reduction can pay higher dividends than increasing storage node capacitance or improving writeability.

Various algorithmic techniques are available for generating music, many of which come from the field of artificial intelligence, which is rich with potential in this regard. However, the musical appropriateness of these techniques is less clearly understood. In this paper, I will report on a study that aimed to describe the characteristics of two of these techniques, rule-based and genetic algorithms, as they apply to melody generation. The appropriateness of these characteristics in contributing to well-formed melodies was judged by aesthetic criteria. The results indicate that most combinations of rules, mutations and evolutionary selection result in poor or average melodies, but that careful combination of these techniques can generate melodies that are not simply well-formed but in many cases display some elegance and novelty.

This paper examines three functions of music technology in the study of music. Firstly as a tool, secondly as an instrument and lastly as a medium for thinking. As our societies become increasingly embroiled in digital media for representation and communication, our philosophies of music education need to adapt to integrate these developments while maintaining the essence of music. The foundation of music technology in the 1990s is the digital representation of sound. It is this fundamental shift to a new medium with which to represent sound that carries with it the challenge to address digital technology and its multiple effects on music creation and presentation. In this paper I suggest that music institutions should take a broad and integrated approach to the place of music technology in their courses, based on the understanding of digital representation of sound and these three functions it can serve. Educators should reconsider digital technologies such as synthesizers and computers as music instruments and cognitive amplifiers, not simply as efficient tools.

The presence of antibody to human immunodeficiency virus (HIV) in postpartum women may be inferred by screening the blood of their newborn babies, since maternal IgG antibodies freely cross the placenta. We tested a sample of 10 217 newborns from 10 hospitals covering three areas in Sydney and other metropolitan centres in New South Wales from April to July, 1989. None of the specimens gave a positive test for antibody to HIV. Thus, the prevalence of HIV positive serology in this sample of newborns was found to be zero. It was estimated that the seroprevalence of antibody to HIV among all neonates in the study area was between zero and 0.045% (99% confidence interval). Because newborns are an accessible group for the study of HIV, and can act as surrogates for their mothers, anonymous testing of this sentinel group will remove some of the limitations on generalising the information in the present database of HIV infection in Australia. This study provides baseline data and suggests that there is not a widespread epidemic of HIV infection among heterosexual persons in Australia at the present time and that routine antenatal testing of women for antibody to HIV may not be costeffective. However, it will be Important to repeat this study at regular intervals to detect any increase in HIV seroprevalence.

This paper describes research focusing on the teaching of synthesizer as a musical instrument. The teaching of synthesizer performance in Australian schools is in its infancy but is currently expanding. There is a need to promote excellence and encourage comprehensiveness in this fledgling area. The research reported here used a case study approach to establish initial guidance in the hope that synthesizer performance may grow strongly and contribute constructively to the overall fabric of music education activities in Australia. In particular, it. identifies areas of study which should be included in a synthesizer curriculum and highlights teaching and learning methods which seem to be effective. The paper concludes by addressing the institutional responsibilities, including resource and environment considerations, which support the teaching of synthesizer.

Stroke injury and incomplete long-term stroke recovery remain key health issues in the United States and world-wide. We seek to help identify cellular dysfunction of the motor cortex after stroke, and its possible circuit remodeling during stroke recovery, since this structure is heavily implicated in this biology. We propose to measure evoked motor responses during long-train intracortical microstimulation (LT-ICMS) of motor cortex in the mouse as a method to identify the functional organization of this structure and plasticity following experimental stroke that relates to functional recovery. This work is one of the first to use LT-ICMS in mice after experimental stroke and it is employed in this study because it evokes complex, multi-joint forelimb movements that may match the temporal activity patterns of motor cortical cells during volitional movement and relate to skilled motor behavior. Permanent stroke injury is induced here using photothrombotic occlusion of the distal middle cerebral artery (MCAo) using Rose Bengal dye and green laser photostimulation. Skilled motor behavior is tested using the single pellet reaching task. Each mouse completes 30 days of post-injury or sham-injury single pellet reaching that is followed by an evaluation of cortical forelimb movement representation using LT-ICMS and then histological testing of lesion size and location. LT-ICMS is delivered as 500 millisecond trains of biphasic 200 microsecond pulses (delivered at 333 Hz) via a platinum/iridium microelectrode. The microelectrode is applied to test sites across the motor cortex (354 micron spacing) that are each at a depth of 800 microns. Evoked movements to LT-ICMS are quantified using high-speed video kinematic tracking of the forelimb. Experimental blind conditions are maintained until study completion. Statistics are then used to relate outcomes of behavioral reaching, LT-ICMS, and lesion characteristics. Collectively, the goal of this project is to understand whether (and how) complex movement representations derived by LT-ICMS change during stroke recovery in order to guide rehabilitative and interventional stroke therapies.

Purpose. To compare long-term outcomes of total hip replacement (THR) in patients with or without contamination of the femoral head.Methods. After a mean period of 12 (range, 8–17) years, 104 female and 71 male THR patients aged 47 to 96 (mean, 77) years were reassessed via a self-administered questionnaire, and 25 other THR patients were reassessed by review of case notes. The questionnaires comprised the 12-item Oxford hip score and the European Quality Of Life (EuroQOL). 87 and 88 patients had positive and negative cultures in the donated femoral heads, respectively. The 2 groups were compared with respect to the Oxford hip score, the EuroQOL, and rates of complication and revision surgery.Results. Long-term outcomes of THR patients with or without femoral head contamination were not significantly different. Respectively, the mean Oxford hip scores were 36 and 39 (p=0.4); 16 and 14 patients had the maximum score of 48; 2 and 3 patients scored <10 (mostly owing to aseptic loosening). The respective mean visual analogue scale score of the EuroQOL were 65 and 73 (p=0.07); only the dimension of self care was significantly different between groups (p=0.04). Respectively, 14 and 12 patients had complications (16% vs. 15%, ?2=0.05, p=0.8), whereas 11 and 5 patients had revision surgery (13% vs. 6%, ?2=2.2, p>0.1).Conclusion. Microbiological screening of donated femoral heads plays no role in predicting long-term failure of THR in the donors.