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Defining and describing what we do: Doctrinal legal research
What exactly is doctrinal legal research? And where does the doctrinal methodology ‘fit’ within the spectrum of scientific and social research methodologies undertaken in other disciplines? The practitioner lawyer of the past had little need to reflect on process. The doctrinal research methodology developed intuitively within the common law - a research method at the core of practice. There was no need to justify or classify it within a broader research framework. Modern academic lawyers are facing a different situation. At a time when competition for limited research funds is becoming more intense, and in which interdisciplinary work is highly valued and non-lawyers are involved in the assessment of grant applications, lawyer-applicants who engage in doctrinal research need to be able to explain their methodology more clearly. Doctrinal scholars need to be more open and articulate about their methods. These methods may be different in different contexts. This paper examines the legal research doctrinal method and its place in recent research dialogue. Some commentators are of the view that the doctrinal method is simply scholarship rather than a separate research methodology. Richard Posner even suggests that law is ‘not a field with a distinct methodology, but an amalgam of applied logic, rhetoric, economics and familiarity with a specialized vocabulary and a particular body of texts, practices, and institutions ..’. Therefore, academic lawyers are beginning to realise that the doctrinal research methodology needs clarification for those outside the legal profession and that a discussion about the standing and place of doctrinal research compared to other methodologies is required
Prognostically controlled comparison of dialysis and renal transplantation
Prognostically controlled comparison of dialysis and renal transplantation. Because the comparison of survival in patients with renal failure treated by dialysis and transplantation may be biased by pretreatment prognostic differences in the patients who receive these two therapies, we quantified the pretreatment prognosis of all 430 dialysis and transplant patients who began therapy for end-stage renal disease at two hospitals from 1970 to 1980. Five pretreatment factors had a statistically significant adverse effect on survival: age, duration of diabetes, left ventricular failure, myocardial infarction, and other serious comorbid illness. Dialysis patients had a worse pretreatment prognosis than transplant patients did. When we controlled for these pretreatment differences, the actuarial 5-year patient survivals were 80% for dialysis (D), 79% for cadaver transplantation (CT), and 91% for living donor transplantation (LDT), (P = 0.9 for CT vs. D, and P = 0.05 for LDT vs. D). This similarity in survival with dialysis and cadaver transplantation was quite different from the results obtained when pretreatment prognosis was not controlled; the uncontrolled 5-year patient survivals were 43% for D, 77% for CT, and 89% for LDT (P < 0.001 for CT vs. D, and P < 0.001 for LDT vs. D). Our data suggest that the major factor determining differences in survival with dialysis and renal transplantation is not the relative efficacy of the two treatments but the pretreatment prognostic status of the patients chosen to receive them.Une comparaison contrôlée de façon pronostique entre la dialyse et la transplantation rénale. Puisque la comparaison de la survie des malades en insuffisance rénale traités par dialyse ou par transplantation peut être biaisée par des différences pronostiques pré-thérapeutiques entre les malades qui reçoivent ces deux traitements, nous avons quantifié le pronostic pré-thérapeutique de l'ensemble des 430 malades dialysés et transplantés qui ont commencé le traitement de leur insuffisance rénale dans deux hôpitaux de 1970 à 1980. Cinq facteurs préthérapeutiques possédaient un effet adverse statistiquement significatif sur la survie: l'âge, la durée du diabète, une insuffisance ventriculaire gauche, un infarctus du myocarde, et une autre maladie sérieuse associée. Les dialysés avaient un pronostic pré-thérapeutique plus mauvais que les transplantés. Lorsque nous avons contrôlé ces différences pré-thérapeutiques, la survie actuarielle à 5 ans des malades était de 80% pour la dialyse (D), 79% pour la transplantation cadavérique (CT), et 91% pour la transplantation avec donneur vivant (LDT) (P = 0,9 pour CT contre D, et P = 0,05 pour LDT contre D). Cette similitude de survie en dialyse ou après transplantation cadavérique était très différente des résultats obtenus lorsque le pronostic pré-thérapeutique n'était pas contrôlé; les survies non contrôlées à 5 ans des malades étaient de 43% pour D, 77% pour CT, et 89% pour LDT (P < 0,001 pour CT contre D, et P < 0,001 pour LDT contre D). Nos données suggèrent que le facteur principal déterminant les différences de survie en dialyse ou après transplantation rénale n'est pas l'efficacité relative des deux traitements, mais l'état pronostique pré-thérapeutique des malades choisis pour les recevoir
Planar projections of graphs
We introduce and study a new graph representation where vertices are embedded
in three or more dimensions, and in which the edges are drawn on the
projections onto the axis-parallel planes. We show that the complete graph on
vertices has a representation in planes. In 3
dimensions, we show that there exist graphs with edges that can be
projected onto two orthogonal planes, and that this is best possible. Finally,
we obtain bounds in terms of parameters such as geometric thickness and linear
arboricity. Using such a bound, we show that every graph of maximum degree 5
has a plane-projectable representation in 3 dimensions.Comment: Accepted at CALDAM 202
Glycolysis and the pentose phosphate pathway after human traumatic brain injury: microdialysis studies using 1,2-(13)C2 glucose.
Increased 'anaerobic' glucose metabolism is observed after traumatic brain injury (TBI) attributed to increased glycolysis. An alternative route is the pentose phosphate pathway (PPP), which generates putatively protective and reparative molecules. To compare pathways we employed microdialysis to perfuse 1,2-(13)C2 glucose into the brains of 15 TBI patients and macroscopically normal brain in six patients undergoing surgery for benign tumors, and to simultaneously collect products for nuclear magnetic resonance (NMR) analysis. (13)C enrichment for glycolytic 2,3-(13)C2 lactate was the median 5.4% (interquartile range (IQR) 4.6-7.5%) in TBI brain and 4.2% (2.4-4.4%) in 'normal' brain (P<0.01). The ratio of PPP-derived 3-(13)C lactate to glycolytic 2,3-(13)C2 lactate was median 4.9% (3.6-8.2%) in TBI brain and 6.7% (6.3-8.9%) in 'normal' brain. An inverse relationship was seen for PPP-glycolytic lactate ratio versus PbtO2 (r=-0.5, P=0.04) in TBI brain. Thus, glycolytic lactate production was significantly greater in TBI than 'normal' brain. Several TBI patients exhibited PPP-lactate elevation above the 'normal' range. There was proportionally greater PPP-derived lactate production with decreasing PbtO2. The study raises questions about the roles of the PPP and glycolysis after TBI, and whether they can be manipulated to achieve a better outcome. This study is the first direct comparison of glycolysis and PPP in human brain.We gratefully acknowledge financial support as follows. Study support: Medical Research
Council (Grant Nos. G0600986 ID79068 and G1002277 ID98489) and National Institute for
Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain
Injury and Repair Theme). Authors’ support: I.J. – Medical Research Council (Grant no.
G1002277 ID 98489) and National Institute for Health Research Biomedical Research
Centre, Cambridge; K.L.H.C. – National Institute for Health Research Biomedical Research
Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); C.G. – the
Canadian Institute of Health Research; A.H. – Medical Research Council/ Royal College of
Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and
Raymond and Beverly Sackler Fellowship; D.K.M. and J.D.P. - National Institute for Health
Research Senior Investigator Awards; P.J.H. – National Institute for Health Research
Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist
Fellowship.This is the accepted manuscript version. The final version is available from the Nature Publishing Group http://www.nature.com/jcbfm/journal/v35/n1/full/jcbfm2014177a.html
A Comparison of Oxidative Lactate Metabolism in Traumatically Injured Brain and Control Brain.
Metabolic abnormalities occur after traumatic brain injury (TBI). Glucose is conventionally regarded as the major energy substrate, although lactate can also be an energy source. We compared 3-13C lactate metabolism in TBI with "normal" control brain and muscle, measuring 13C-glutamine enrichment to assess tricarboxylic acid (TCA) cycle metabolism. Microdialysis catheters in brains of nine patients with severe TBI, five non-TBI brain surgical patients, and five resting muscle (non-TBI) patients were perfused (24 h in brain, 8 h in muscle) with 8 mmol/L sodium 3-13C lactate. Microdialysate analysis employed ISCUS and nuclear magnetic resonance. In TBI, with 3-13C lactate perfusion, microdialysate glucose concentration increased nonsignificantly (mean +11.9%, p = 0.463), with significant increases (p = 0.028) for lactate (+174%), pyruvate (+35.8%), and lactate/pyruvate ratio (+101.8%). Microdialysate 13C-glutamine fractional enrichments (median, interquartile range) were: for C4 5.1 (0-11.1) % in TBI and 5.7 (4.6-6.8) % in control brain, for C3 0 (0-5.0) % in TBI and 0 (0-0) % in control brain, and for C2 2.9 (0-5.7) % in TBI and 1.8 (0-3.4) % in control brain. 13C-enrichments were not statistically different between TBI and control brain, showing both metabolize 3-13C lactate via TCA cycle, in contrast to muscle. Several patients with TBI exhibited 13C-glutamine enrichment above the non-TBI control range, suggesting lactate oxidative metabolism as a TBI "emergency option."Medical Research Council (Grant Nos. G0600986 ID79068 and G1002277 ID98489) and National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme). Authors’ support: IJ – Medical Research Council (Grant no. G1002277 ID 98489) and National Institute for Health Research Biomedical Research Centre, Cambridge; KLHC – National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); CG – the Canadian Institute of Health Research; AH – Medical Research Council/Royal College of Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and Raymond and Beverly Sackler Fellowship; Royal College of Surgeons of England and the NIHR Cambridge Biomedical Research Centre; DKM and JDP – National Institute for Health Research Senior Investigator Awards; MPM - Medical Research Council UK (MC_U105663142) and a Wellcome Trust Investigator award (110159/Z/15/Z). PJH – National Institute for Health Research Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist Fellowship and the National Institute for Health Research Biomedical Research Centre, Cambridge
13C-labelled microdialysis studies of cerebral metabolism in TBI patients
AbstractHuman brain chemistry is incompletely understood and better methodologies are needed. Traumatic brain injury (TBI) causes metabolic perturbations, one result of which includes increased brain lactate levels. Attention has largely focussed on glycolysis, whereby glucose is converted to pyruvate and lactate, and is proposed to act as an energy source by feeding into neurons’ tricarboxylic acid (TCA) cycle, generating ATP. Also reportedly upregulated by TBI is the pentose phosphate pathway (PPP) that does not generate ATP but produces various molecules that are putatively neuroprotective, antioxidant and reparative, in addition to lactate among the end products.We have developed a novel combination of 13C-labelled cerebral microdialysis both to deliver 13C-labelled substrates into brains of TBI patients and recover the 13C-labelled metabolites, with high-resolution 13C NMR analysis of the microdialysates. This methodology has enabled us to achieve the first direct demonstration in humans that the brain can utilise lactate via the TCA cycle. We are currently using this methodology to make the first direct comparison of glycolysis and the PPP in human brain.In this article, we consider the application of 13C-labelled cerebral microdialysis for studying brain energy metabolism in patients. We set this methodology within the context of metabolic pathways in the brain, and 13C research modalities addressing them
Focally perfused succinate potentiates brain metabolism in head injury patients.
Following traumatic brain injury, complex cerebral energy perturbations occur. Correlating with unfavourable outcome, high brain extracellular lactate/pyruvate ratio suggests hypoxic metabolism and/or mitochondrial dysfunction. We investigated whether focal administration of succinate, a tricarboxylic acid cycle intermediate interacting directly with the mitochondrial electron transport chain, could improve cerebral metabolism. Microdialysis perfused disodium 2,3-13C2 succinate (12 mmol/L) for 24 h into nine sedated traumatic brain injury patients' brains, with simultaneous microdialysate collection for ISCUS analysis of energy metabolism biomarkers (nine patients) and nuclear magnetic resonance of 13C-labelled metabolites (six patients). Metabolites 2,3-13C2 malate and 2,3-13C2 glutamine indicated tricarboxylic acid cycle metabolism, and 2,3-13C2 lactate suggested tricarboxylic acid cycle spinout of pyruvate (by malic enzyme or phosphoenolpyruvate carboxykinase and pyruvate kinase), then lactate dehydrogenase-mediated conversion to lactate. Versus baseline, succinate perfusion significantly decreased lactate/pyruvate ratio (p = 0.015), mean difference -12%, due to increased pyruvate concentration (+17%); lactate changed little (-3%); concentrations decreased for glutamate (-43%) (p = 0.018) and glucose (-15%) (p = 0.038). Lower lactate/pyruvate ratio suggests better redox status: cytosolic NADH recycled to NAD+ by mitochondrial shuttles (malate-aspartate and/or glycerol 3-phosphate), diminishing lactate dehydrogenase-mediated pyruvate-to-lactate conversion, and lowering glutamate. Glucose decrease suggests improved utilisation. Direct tricarboxylic acid cycle supplementation with 2,3-13C2 succinate improved human traumatic brain injury brain chemistry, indicated by biomarkers and 13C-labelling patterns in metabolites.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Medical Research Council (Grant Nos. G0600986 ID79068 and G1002277 ID98489) and National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme). Authors’ support: IJ – Medical Research Council (Grant no. G1002277 ID 98489) and National Institute for Health Research Biomedical Research Centre, Cambridge; KLHC – National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); CG – the Canadian Institute of Health Research; AH – Medical Research Council/Royal College of Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and Raymond and Beverly Sackler Fellowship; DKM and JDP – National Institute for Health Research Senior Investigator Awards; PJH – National Institute for Health Research Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist Fellowship and the National Institute for Health Research Biomedical Research Centre, Cambridge
Motor Control and Sensory Feedback Enhance Prosthesis Embodiment and Reduce Phantom Pain After Long-Term Hand Amputation
We quantified prosthesis embodiment and phantom pain reduction associated with motor control and sensory feedback from a prosthetic hand in one human with a long-term transradial amputation. Microelectrode arrays were implanted in the residual median and ulnar arm nerves and intramuscular electromyography recording leads were implanted in residual limb muscles to enable sensory feedback and motor control. Objective measures (proprioceptive drift) and subjective measures (survey answers) were used to assess prosthesis embodiment. For both measures, there was a significant level of embodiment of the physical prosthetic limb after open-loop motor control of the prosthesis (i.e., without sensory feedback), open-loop sensation from the prosthesis (i.e., without motor control), and closed-loop control of the prosthesis (i.e., motor control with sensory feedback). There was also a statistically significant reduction in reported phantom pain after experimental sessions that included open-loop nerve microstimulation, open-loop prosthesis motor control, or closed-loop prosthesis motor control. The closed-loop condition provided no additional significant improvements in phantom pain reduction or prosthesis embodiment relative to the open-loop sensory condition or the open-loop motor condition. This study represents the first long-term (14-month), systematic report of phantom pain reduction and prosthesis embodiment in a human amputee across a variety of prosthesis use cases
Broad Down, Devon: archaeological and other stories
publication-status: PublishedThis is a post-print, author-produced version of an article accepted for publication
Journal of Material Culture, 2010, Vol. 15, Issue 3, pp. 345 - 367. Copyright © 2010 SAGE Publications. The definitive publisher-authenticated version is available online at http://mcu.sagepub.com/content/15/3/345.shortThis article explores the knowledge construction process of an archaeological site in East Devon, UK. Bouncing off an oral historical account of the site that seems to run against scientific truth claims, the author investigates the story of how knowledge of the site has developed over the last two centuries. Building on previous work that explores the history and practice of archaeology, the article opens up questions of what counts as evidence. Then, taking a cue from more recent work that suggests a more dynamic and open-ended engagement with the landscape, the article turns to examine how the meaning of a site can be made and remade. As part of this endeavour, questions of what as well as who can ‘speak’ are examined and some space is opened up for the agency of ‘minor figures’, both human and non-human
24-h sheltering behaviour of individually kept horses during Swedish summer weather
Provision of shelter for horses kept on summer pasture is rarely considered in welfare guidelines, perhaps because the benefits of shelter in warm conditions are poorly documented scientifically. For cattle, shade is a valued resource during summer and can mitigate the adverse effects of warm weather on well-being and performance. We found in a previous study that horses utilized shelters frequently in summer. A shelter with a roof and closed on three sides (shelter A) was preferred and can reduce insect pressure whereas a shelter with roof and open on three sides was not utilized. However, shelter A restricts the all-round view of a horse, which may be important for horses as flight animals. Therefore, we studied whether a shelter with roof, where only the upper half of the rear wall was closed (shelter B), would be utilized while maintaining insect protection properties and satisfying the horses’ sense for security. A third shelter was offered with walls but no roof (shelter C) to evaluate whether the roof itself is an important feature from the horse’s perspective. Eight Warmblood horses were tested each for 2 days, kept individually for 24 h in two paddocks with access to shelters A and B, or shelters A and C, respectively. Shelter use was recorded continuously during the night (1800–2400 h, 0200–0600 h) and the following day (0900–1600 h), and insect defensive behaviour (e.g., tail swish) in instantaneous scan samples at 5-min intervals during daytime
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