University of New South Wales

About: University of New South Wales is a education organization based out in Sydney, New South Wales, Australia. It is known for research contribution in the topics: Population & Poison control. The organization has 51197 authors who have published 153634 publications receiving 4880608 citations. The organization is also known as: UNSW & UNSW Australia.

Liquid junction potentials and small cell effects in patch-clamp analysis.

Abstract: Since the early 1980s, the patch-clamp technique (Hamill et al., 1981) has been of particular value in investigating the properties of ion channels in cells. When used in either the intact or excised configurations, the properties of individual ionic channels can be directly measured. In addition, the whole-cell configuration can be used to investigate the total response of the full complement of channels in a cell. The whole-cell configuration is of particular value in exploring the properties of very small cells which are not readily accessible to conventional microelectrode techniques. in all of the above measurements, there are two potential sources of error, in every situation there may be significant errors due to uncompensated junction potentials, which m a y a p p e a r to be eliminated by the normal zeroing procedure whereby residual potentials between pipette and bath solutions are offset prior to patch formation. In addition, in the intact and whole-cell patch configurations, the effect of the cells being small can introduce radical errors in the measurement of single-channel and whole-cell properties. The aim of this review is firstly to outline the contribution of such junction potentials and the errors resulting from measurements on small cells and secondly to indicate how adequate junction potential corrections can be applied and the true values of underlying membrane parameters determined for such cells. Where necessary, appropriate equations have been presented. Much of the material is a review of published work. However, the review also seeks to extend the implications of that work and, in particular, it also includes (in an appendix) a timedependent solution of the current relaxation following a channel closure.

The Psychiatric Sequelae of Traumatic Injury

Abstract: ObjectiveTraumatic injury affects millions of people each year. There is little understanding of the extent of psychiatric illness that develops after traumatic injury or of the impact of mild traumatic brain injury (TBI) on psychiatric illness. The authors sought to determine the range of new psychiatric disorders occurring after traumatic injury and the influence of mild TBI on psychiatric status. MethodIn this prospective cohort study, patients were drawn from recent admissions to four major trauma hospitals across Australia. A total of 1,084 traumatically injured patients were initially assessed during hospital admission and followed up 3 months (N=932, 86%) and 12 months (N=817, 75%) after injury. Lifetime psychiatric diagnoses were assessed in hospital. The prevalence of psychiatric disorders, levels of quality of life, and mental health service use were assessed at the follow-ups. The main outcome measures were 3- and 12-month prevalence of axis I psychiatric disorders, levels of quality of life, a...

Selective neuronal vulnerability in Parkinson disease.

Abstract: Intracellular α-synuclein (α-syn)-rich protein aggregates called Lewy pathology (LP) and neuronal death are commonly found in the brains of patients with clinical Parkinson disease (cPD). It is widely believed that LP appears early in the disease and spreads in synaptically coupled brain networks, driving neuronal dysfunction and death. However, post-mortem analysis of human brains and connectome-mapping studies show that the pattern of LP in cPD is not consistent with this simple model, arguing that, if LP propagates in cPD, it must be gated by cell- or region-autonomous mechanisms. Moreover, the correlation between LP and neuronal death is weak. In this Review, we briefly discuss the evidence for and against the spreading LP model, as well as evidence that cell-autonomous factors govern both α-syn pathology and neuronal death.

Single-shot readout of an electron spin in silicon.

Abstract: The size of silicon transistors used in microelectronic devices is shrinking to the level at which quantum effects become important. Although this presents a significant challenge for the further scaling of microprocessors, it provides the potential for radical innovations in the form of spin-based quantum computers and spintronic devices. An electron spin in silicon can represent a well-isolated quantum bit with long coherence times because of the weak spin-orbit coupling and the possibility of eliminating nuclear spins from the bulk crystal. However, the control of single electrons in silicon has proved challenging, and so far the observation and manipulation of a single spin has been impossible. Here we report the demonstration of single-shot, time-resolved readout of an electron spin in silicon. This has been performed in a device consisting of implanted phosphorus donors coupled to a metal-oxide-semiconductor single-electron transistor-compatible with current microelectronic technology. We observed a spin lifetime of ∼6 seconds at a magnetic field of 1.5 tesla, and achieved a spin readout fidelity better than 90 per cent. High-fidelity single-shot spin readout in silicon opens the way to the development of a new generation of quantum computing and spintronic devices, built using the most important material in the semiconductor industry.