Optimal Imaging of Remote Bodies Using Quantum Detectors.

We implement a general imaging method by measuring the complex degree of coherence using linear optics and photon number resolving detectors. In the absence of collective or entanglement-assisted measurements, our method is optimal over a large range of practically relevant values of the complex degree of coherence. We measure the size and position of a small distant source of pseudothermal light, and show that our method outperforms the traditional imaging method by an order of magnitude in precision. Finally, we show that a lack of photon-number resolution in the detectors has only a modest detrimental effect on measurement precision and simulate imaging using the new and traditional methods with an array of detectors, showing that the new method improves both image clarity and contrast.

Recurrent rhabdomyolysis caused by carnitine palmitoyltransferase II deficiency, common but under-recognised: Lessons to be learnt.

We discuss two adult siblings who presented with symptoms of myalgia and rhabdomyolysis following exercise with myoglobinuria; genetic testing confirmed carnitine palmitoyltransferase II deficiency and resulted in institution of appropriate crisis management and dietary advice. We explore the phenotypic variability of this commonest fatty oxidation defect that remains under-diagnosed in the adult population and provide clues for early recognition and diagnosis.

The current role of decompressive craniectomy for severe traumatic brain injury.

There is little doubt that decompressive craniectomy can reduce mortality however, the results of a recent study has provided more evidence to inform the debate regarding clinical and ethical concerns that it merely converts death into survival with severe disability or in a vegetative state. The recently published RESCUEicp trial compared last-tier secondary decompressive craniectomy with continued medical management for refractory intracranial hypertension after severe traumatic brain injury. Patients were randomly assigned to decompressive craniectomy with medical therapy or to receive continued medical therapy with the option of adding barbiturates. The results of the study support the findings of the stroke studies in that the reduction in mortality was almost directly translatable into survival with either severe disability or in a vegetative state. The question remains as to whether there is a subset of patients who obtain benefit from surgical decompression and it is in this regard that the use of observational cohort studies and sophisticated outcome prediction models may be of use. Comparing the percentage prediction with the observed long outcome provides an objective assessment of the most likely outcome can be obtained for patients thought to require surgical intervention. Whilst there will always be limitations when using this type of data they may help prompt appropriate patient-centred discussions regarding realistic outcome expectations. A broader debate is also needed regarding use of a medical intervention that may leave a person in a condition that they may feel to be unacceptable and also places a considerable burden on society.

Reconsidering the role of decompressive craniectomy for neurological emergencies.

OBJECTIVE: There is little doubt that decompressive craniectomy can reduce mortality. However, there is concern that any reduction in mortality comes at an increase in the number of survivors with severe neurological disability. METHOD: Over the past decade there have been several randomised controlled trials comparing surgical decompression with standard medical therapy in the context of ischaemic stroke and severe traumatic brain injury. The results of each trial are evaluated. RESULTS: There is now unequivocal evidence that a decompressive craniectomy reduces mortality in the context of "malignant" middle infarction and following severe traumatic brain injury. However, it has only been possible to demonstrate an improvement in outcome by categorizing a mRS of 4 and upper severe disability as favourable outcome. This is contentious and an alternative interpretation is that surgical decompression reduces mortality but exposes a patient to a greater risk of survival with severe disability. CONCLUSION: It would appear unlikely that further randomised controlled trials will be possible given the significant reduction in mortality achieved by surgical decompression. It may be that observational cohort studies and outcome prediction models may provide data to determine those patients most likely to benefit from surgical decompression.

Intensive care unit research ethics and trials on unconscious patients.

There are widely acknowledged ethical issues in enrolling unconscious patients in research trials, particularly in intensive care unit (ICU) settings. An analysis of those issues shows that, by and large, patients are better served in units where research is actively taking place for several reasons: i) they do not fall prey to therapeutic prejudices without clear evidential support, ii) they get a chance of accessing new and potentially beneficial treatments, iii) a climate of careful monitoring of patients and their clinical progress is necessary for good clinical research and affects the care of all patients and iv) even those not in the treatment arm of a trial of a new intervention must receive best current standard care (according to international evidence-based treatment guidelines). Given that we have discovered a number of 'best practice' regimens of care that do not optimise outcomes in ICU settings, it is of great benefit to all patients (including those participating in research) that we are constantly updating and evaluating what we do. Therefore, the practice of ICU-based clinical research on patients, many of whom cannot give prospective informed consent, ticks all the ethical boxes and ought to be encouraged in our health system. It is very important that the evaluation of protocols for ICU research should not overlook obvious (albeit probabilistic) benefits to patients and the acceptability of responsible clinicians entering patients into well-designed trials, even though the ICU setting does not and cannot conform to typical informed consent procedures and requirements.

Experimental distribution of entanglement with separable carriers.

The key requirement for quantum networking is the distribution of entanglement between nodes. Surprisingly, entanglement can be generated across a network without direct transfer-or communication-of entanglement. In contrast to information gain, which cannot exceed the communicated information, the entanglement gain is bounded by the communicated quantum discord, a more general measure of quantum correlation that includes but is not limited to entanglement. Here, we experimentally entangle two communicating parties sharing three initially separable photonic qubits by exchange of a carrier photon that is unentangled with either party at all times. We show that distributing entanglement with separable carriers is resilient to noise and in some cases becomes the only way of distributing entanglement through noisy environments.

Neurotrauma and the rule of rescue.

The rule of rescue describes the powerful human proclivity to rescue identified endangered lives, regardless of cost or risk. Deciding whether or not to perform a decompressive craniectomy as a life-saving or 'rescue' procedure for a young person with a severe traumatic brain injury provides a good example of the ethical tensions that occur in these situations. Unfortunately, there comes a point when the primary brain injury is so severe that if the patient survives they are likely to remain severely disabled and fully dependent. The health resource implications of this outcome are significant. By using a web-based outcome prediction model this study compares the long-term outcome and designation of two groups of patients. One group had a very severe injury as adjudged by the model and the other group a less severe injury. At 18 month follow-up there were significant differences in outcome and healthcare requirements. This raises important ethical issues when considering life-saving but non-restorative surgical intervention. The discussion about realistic outcome cannot be dichotomised into simply life or death so that the outcome for the patient must enter the equation. As in other 'rescue situations', the utility of the procedure cannot be rationalised on a mere cost-benefit analysis. A compromise has to be reached to determine at what point either the likely outcome would be unacceptable to the person on whom the procedure is being performed or the social utility gained from the rule of rescue intervention fails to justify the utilitarian value and justice of equitable resource allocation.

The influence of objective prognostic information on the likelihood of informed consent for decompressive craniectomy: a study of Australian anaesthetists.

The aim of this study was to assess the influence of detailed prognostic information on the likelihood of informed consent for decompressive craniectomy for severe traumatic brain injury. The study was a simulation exercise, asking anaesthetists to give opinions as if they themselves were the injured party. Anaesthetists were chosen as they represent a distinct group likely to be familiar with the procedure and the decision-making process, but not necessarily aware of the longer-term outcomes. A two-part structured interview was used. Seventy-five anaesthetists were shown three cases of differing severity of traumatic brain injury. A visual analogue scale (1 to 10) was used to assess the strengths of their opinion. Initially they were asked their opinion with no predictive outcome data. They were then shown the prediction of an unfavourable outcome (Glasgow Outcome Scale severely disabled, vegetative state or dead) and the observed outcome at 18-month follow-up from a cohort of 147 patients (who had had a decompressive craniectomy for severe traumatic brain injury in Perth, Western Australia between the years 2004 and 2008). The opinions of the participants before and after seeing the prediction outcome data were compared. The participants' preferences to consent to the procedure changed after being informed of the predicted risks of unfavourable outcomes (P values < 0.01). The changes in attitude appeared to be independent of age group, amount of experience in caring for similar patients and religious background. These findings suggest that access to objective information on risks of unfavourable outcomes may influence opinions in relation to consent for decompressive craniectomy for traumatic brain injury.

Towards quantum chemistry on a quantum computer.

Exact first-principles calculations of molecular properties are currently intractable because their computational cost grows exponentially with both the number of atoms and basis set size. A solution is to move to a radically different model of computing by building a quantum computer, which is a device that uses quantum systems themselves to store and process data. Here we report the application of the latest photonic quantum computer technology to calculate properties of the smallest molecular system: the hydrogen molecule in a minimal basis. We calculate the complete energy spectrum to 20 bits of precision and discuss how the technique can be expanded to solve large-scale chemical problems that lie beyond the reach of modern supercomputers. These results represent an early practical step toward a powerful tool with a broad range of quantum-chemical applications.

Neurotrauma and the RUB: where tragedy meets ethics and science.

Decompressive craniectomy is a technically straightforward procedure whereby a large section of the cranium is temporarily removed in cases where the intracranial pressure is dangerously high. While its use has been described for a number of conditions, it is increasingly used in the context of severe head injury. As the use of the procedure increases, a significant number of patients may survive a severe head injury who otherwise would have died. Unfortunately some of these patients will be left severely disabled; a condition likened to the RUB, an acronym for the Risk of Unacceptable Badness. Until recently it has been difficult to predict this outcome, however an accurate prediction model has been developed and this has been applied to a large cohort of patients in Western Australia. It is possible to compare the predicted outcome with the observed outcome at 18 months within this cohort. By using predicted and observed outcome data this paper considers the ethical implications in three cases of differing severity of head injury in view of the fact that it is possible to calculate the RUB for each case.

Experimental feedback control of quantum systems using weak measurements.

A goal of the emerging field of quantum control is to develop methods for quantum technologies to function robustly in the presence of noise. Central issues are the fundamental limitations on the available information about quantum systems and the disturbance they suffer in the process of measurement. In the context of a simple quantum control scenario-the stabilization of nonorthogonal states of a qubit against dephasing-we experimentally explore the use of weak measurements in feedback control. We find that, despite the intrinsic difficultly of implementing them, weak measurements allow us to control the qubit better in practice than is even theoretically possible without them. Our work shows that these more general quantum measurements can play an important role for feedback control of quantum systems.

Overlap of premature birth and permissible abortion.

Abortion is permitted in many jurisdictions after the age at which an infant is viable on the basis of intensive neonatal care techniques. Does this cause special concerns for those involved in perinatal care and termination of pregnancy services or is the overlap mainly an abstract issue fretted over by ethicists and academics? In order to explore this question, a group of clinicians involved in this area of care were interviewed and their interviews analysed using qualitative measures. The clinicians concerned were exercised by the ethical issues and had various ways of resolving them which tended to reflect a gradualist, multifaceted and, to some extent, particularist approach to ethical decision-making in relation to the edges of human life. The ways in which those strands of ethical thought are instanced in the interview material are reported and discussed.

Cyborgs and moral identity.

Neuroscience and technological medicine in general increasingly faces us with the imminent reality of cyborgs-integrated part human and part machine complexes. If my brain functions in a way that is supported by and exploits intelligent technology both external and implantable, then how should I be treated and what is my moral status-am I a machine or am I a person? I explore a number of scenarios where the balance between human and humanoid machine shifts, and ask questions about the moral status of the individuals concerned. The position taken is very much in accordance with the Aristotelian idea that our moral behaviour is of a piece with our social and personal skills and forms a reactive and reflective component of those skills.

The unwitting sacrifice problem.

The diagnosis of bipolar disorder has been linked to giftedness of various sorts and this raises a special problem in that it is likely that the condition has a genetic basis. Therefore it seems possible that in the near future we will be able to detect and eliminate the gene predisposing to the disorder. This may mean, however, that, as a society, we lose the associated gifts. We might then face a difficult decision either way in that it is unclear that we are preventing an unalloyed bad when we diagnose and eliminate bipolar disorder through prenatal genetic testing and yet if we allow the individual to be born we are condemning that person to being an unwitting sacrifice in that they might well suffer considerable net distress as a result of our need to keep our gene pool enriched in the relevant way.

Spinal epidural empyema.

Spinal epidural empyema is a very rare entity occurring with an estimated incidence of 1 per 10,000 hospital admissions. This condition has a reputation for presenting as a diagnostic challenge resulting in late diagnosis and delayed treatment. However, the cornerstones of treatment are prompt diagnosis and early treatment to prevent permanent paralysis and high mortality. We present a cluster of nine cases presenting to the neurosurgery unit over a 3-year period and discuss their relevant features in view of the most recent literature. The diagnosis of spinal epidural empyema was made with gadolinium-enhanced MRI in eight of nine cases. Staphylococcus aureus was isolated as the causative pathogen in all cases. All patients were treated with antibiotics. Eight patients had surgery for debridement and spinal decompression. One patient was treated successfully with antibiotics alone.

An ethics core curriculum for Australasian medical Schools.

Teaching ethics incorporates teaching of knowledge as well as skills and attitudes. Each of these requires different teaching and assessment methods. A core curriculum of ethics knowledge must address both the foundations of ethics and specific ethical topics. Ethical skills teaching focuses on the development of ethical awareness, moral reasoning, communication and collaborative action skills. Attitudes that are important for medical students to develop include honesty, integrity and trustworthiness, empathy and compassion, respect, and responsibility, as well as critical self-appraisal and commitment to lifelong education.