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.

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.

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.

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.

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.

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.

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.

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.

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.

Ethics and dental research.

Dentistry is a Hippocratic profession and is therefore committed to ongoing research into the causes and treatments of disease. This research embodies ethical standards which place a high value on a respect for persons. Those standards emphasize that we obtain informed consent from individuals selected to participate in research. The relevant information required for informed consent varies from situation to situation but should take into account the need for participants to make a reasoned decision about their involvement. Where community research is involved, there should be consultation with appropriate representatives. In all contemporary medical research, there is an inherent conflict between the ethical requirement that we share information which will help those who are suffering and the need to preserve rights to competitively sensitive information related to product development and academic funding. These various pressures on research emphasize the need for an active and lively appreciation of ethical issues in contemporary biomedical sciences.

Mediodorsal nucleus and behavior regulation in the rat.

Twelve electrodes aimed at the mediodorsal thalamic nucleus were implanted in 6 rats. In 5 of these animals intracranial stimulation was effective in punishing a bar press response on a baseline schedule of water reinforcement. The sixth animal was not tested. In all 6 animals lesions produced through these electrodes disrupted response suppression to punishing electric shock superimposed on the same baseline. Those animals in which both parts of the mediodorsal thalamic nucleus were damaged showed a more marked and graded punishment effect of intracranial stimulation and a more profound disruption of the quantitative shock intensity-response relationship than those in which only the rostromedial part of the nucleus was damaged. Three other animals had electrodes implanted in the rostromedial hypothalamus or the midline thalamus. They showed neither the punishing effect of intracranial stimulation nor the dusruptive effect on response suppression of electrocoagulative lesions.

Beyond the orthodox: heresy in medicine and social science.

Kuhn's seminal work on scientific revolutions has undermined any strong claim to the idea that there is one single true theory about the way nature is. Both social science and medicine share, in differing ways, the uncertainty produced by the complexity of the human condition. This is not well accommodated by the traditional medicine model. There are both individual diseases and individual responses to disease that require a more holistic response to the patient. The holistic responses to these problems show promise but require careful evaluation through critical reflection on our practice of medicine.

Hypothalamic glioma.

Seven patients from a series of 400 parasellar lesions presenting with visual failure treated in the Gough-Cooper Department of Neurological Surgery, The National Hospital for Nervous Diseases, Queen Square, were found to have low-grade gliomas of the hypothalamus. All were retrochiasmatic in site. The median age was 18 years. All showed low-grade astrocytoma, grade 2 and, in 6 of the 7 cases, presentation was with a variety of visual problems including homonymous hemianopia, bitemporal hemianopia, and unilateral scotomata. The other case presented with papilledema. Skull x-rays were, by and large, normal. Computed tomography scanning showed low- or mixed-density midline lesions and angiography showed mass effect and occasionally a capsular blush. All were operated on directly through a variety of approaches, and in each case, a radical subtotal removal was carried out. Postoperatively there were no major complications and no major worsening of symptoms in any patient. Radiotherapy was applied in 6 of the 7 cases. Follow-up periods range from 6 months to 6 years and 5 of the 7 patients remain well. The other 2, who are surviving, have advancing neurological disturbance.

Ethics, brain damage and ending lives.

The problem of patients in the persistent vegetative state is beset by complex ethical and philosophical issues to do with the nature of persons and our ethical duties towards them. Many discussions obscure the main ethical considerations. In this paper, I approach the problem through a philosophical analysis of the concept of a person and the attributes that ground our ethical responsibilities to persons. I argue that we are under no ethical obligation to continue lifesustaining treatment for patients properly diagnosed as being in the persistent vegetative state or with other severe brain damaged conditions. This, of course, is compatible with our trying to do our best for such patients until the prognosis is clear.

Innovative treatments: ethical requirements for evaluation.

An innovative surgical treatment may arise as a deliberate strategy to solve a clinical problem or as a serendipitous discovery in the course of clinical care. In either case there is a need to evaluate the procedure and there are ethical requirements on such evaluation concerning the reasons for its introduction, patient consent, patient safety and clinical efficacy. Some of these ethical considerations may tell against a randomized controlled trial but the need for monitoring and evaluation along with genuine informed consent remain as absolute requirements. Two cases are introduced and discussed, one of which concerns potentially dangerous surgery and the other a new technology. In each case the ethical requirements are examined and discussed and the possible substitutes for prospective randomized controlled studies in clinical surgery are explored. It is concluded that there are defensible and scientific ways to introduce surgical innovation even where the 'gold standard' of a prospective randomized controlled trial cannot be met.

Should doctors be more proactive as advocates for victims of violence?

Currently the management of adult victims of violence by general practitioners and accident and emergency departments is reactive, concerned almost exclusively with the management of physical injuries. Professor Jonathan Shepherd outlines some ideas for a more proactive approach on the part of doctors to improve the protection and support of vulnerable people; to deal with psychological sequelae; to take the responsibility of making an official complaint to the police away from seriously injured people, who are unable to give or withhold consent to disclosure; and to prevent assailants inflicting further injuries. We asked a sociologist, a psychiatrist, a moral philosopher, and a police surgeon for their comments.

Doctors' legal position in treating temporarily incompetent patients.

Doctors in accident and emergency departments are sometimes presented with patients with potentially life threatening conditions who refuse to consent to treatment. The doctors then face a dilemma: to withhold necessary treatment or to act against a patient's express wishes. Two such cases are presented, and we asked a lawyer, two medical ethicists, a psychiatrist, and an accident and emergency physician to comment on the implications.

Euthanasia from the perspective of hospice care.

The hospice believes in the concept of a gentle and harmonious death. In most hospice settings there is also a rejection of active euthanasia. This set of two apparently conflicting principles can be defended on the basis of two arguments. The first is that doctors should not foster the intent to kill as part of their moral and clinical character. This allows proper sensitivity to the complex and difficult situation that arises in many of the most difficult terminal care situations. The second argument turns on the seduction of technological solutions to human problems and the slippery slope that may arise in the presence of a quick and convenient way of dealing with problems of death and dying.