1,421 research outputs found
Perturbative expansion of N<8 Supergravity
We characterise the one-loop amplitudes for N=6 and N=4 supergravity in four
dimensions. For N=6 we find that the one-loop n-point amplitudes can be
expanded in terms of scalar box and triangle functions only. This
simplification is consistent with a loop momentum power count of n-3, which we
would interpret as being n+4 for gravity with a further -7 from the N=6
superalgebra. For N=4 we find that the amplitude is consistent with a loop
momentum power count of n, which we would interpret as being n+4 for gravity
with a further -4 from the N=4 superalgebra. Specifically the N=4 amplitudes
contain non-cut-constructible rational terms.Comment: 13 pages. v2 adds analytic expression for rational parts of 5-pt
1-loop N=4 SUGRA amplitude; v3 normalisations clarifie
Obtaining One-loop Gravity Amplitudes Using Spurious Singularities
The decomposition of a one-loop scattering amplitude into elementary
functions with rational coefficients introduces spurious singularities which
afflict individual coefficients but cancel in the complete amplitude. These
cancellations create a web of interactions between the various terms. We
explore the extent to which entire one-loop amplitudes can be determined from
these relationships starting with a relatively small input of initial
information, typically the coefficients of the scalar integral functions as
these are readily determined. In the context of one-loop gravity amplitudes, of
which relatively little is known, we find that some amplitudes with a small
number of legs can be completely determined from their box coefficients. For
increasing numbers of legs, ambiguities appear which can be determined from the
physical singularity structure of the amplitude. We illustrate this with the
four-point and N=1,4 five-point (super)gravity one-loop amplitudes.Comment: Minor corrections. Appendix adde
The army isn\u27t all work : Physical culture in the evolution of the British army, 1860-1920
Between the Crimean War and the end of WWI the British Army underwent a dramatic change from being an anachronistic and frequently ineffective organization to being perhaps the most professional and highly trained army in the world. British Army physical culture was a central part of that transformation. It acted as a significant bridge between the Army and its parent society, over which flowed ideas and values in both directions. An investigation of the Army\u27s physical culture provides an excellent means of gaining a clear understanding of how this transformation occurred. This dissertation does two primary things: First, it documents the origins and development of formal physical training in the late Victorian Army, and the ways in which the Army\u27s gymnastic training evolved into what was perhaps the most important building block of the process of making a civilian into a fighting man. Second, it assesses the nature and extent of British m~litary sport, particularly regimental sports, during the Victorian period and throuzh WWI. During WWI the pre-war programs of physical training and command-sponsored games acted as a powerful means of assimilating the Commonwealth\u27s civilian-soldiers. and then ensured that they were physically and mentally prepared for the rigors of fighting. Additionally, these same programs had been used since the middle of the nineteenth century to improve the perceived military effectiveness of Britain\u27s imperial troops, and to inculcate them with the same ethos of athleticism that was a seminal part of the British Army\u27s philosophy of training and leadership. The role of sport and physical training in the process of remaking the Army between 1860 and 1920 is only a small piece of the whole, but a critical one. British Army physical culture before and during WWI was an integral part of the Army\u27s modem and highly effective training program. Much of current research on both WWI and the period before has tended to emphasize the unprepared and unprofessional nature of Britain\u27s army; my research not only suggests the contrary, but that sport and physical training in the Army were major contributors to the Army\u27s effectiveness throughout the period
The n-point MHV one-loop Amplitude in N=4 Supergravity
We present an explicit formula for the n-point MHV one-loop amplitude in a
N=4 supergravity theory. This formula is derived from the soft and collinear
factorisations of the amplitude.Comment: 8 pages; v2 References added. Minor changes to tex
Interrelationship of visual perceptual deficits, self-concept, and reading achievement
This study was undertaken to sort out the myriad of studies dealing with visual perception and its effects on reading achievement and self-concept
The TrueBlue study : is practice nurse-led collaborative care effective in the management of depression for patients with heart disease or diabetes?
Background: In the presence of type 2 diabetes (T2DM) or coronary heart disease (CHD), depression is under diagnosed and under treated despite being associated with worse clinical outcomes. Our earlier pilot study demonstrated that it was feasible, acceptable and affordable for practice nurses to extend their role to include screening for and monitoring of depression alongside biological and lifestyle risk factors. The current study will compare the clinical outcomes of our model of practice nurse-led collaborative care with usual care for patients with depression and T2DM or CHD.Methods: This is a cluster-randomised intervention trial. Eighteen general practices from regional and metropolitan areas agreed to join this study, and were allocated randomly to an intervention or control group. We aim to recruit 50 patients with co-morbid depression and diabetes or heart disease from each of these practices. In the intervention group, practice nurses (PNs) will be trained for their enhanced roles in this nurse-led collaborative care study. Patients will be invited to attend a practice nurse consultation every 3 months prior to seeing their usual general practitioner. The PN will assess psychological, physiological and lifestyle parameters then work with the patient to set management goals. The outcome of this assessment will form the basis of a GP Management Plan document. In the control group, the patients will continue to receive their usual care for the first six months of the study before the PNs undergo the training and switch to the intervention protocol. The primary clinical outcome will be a reduction in the depression score. The study will also measure the impact on physiological measures, quality of life and on patient attitude to health care delivered by practice nurses.Conclusion: The strength of this programme is that it provides a sustainable model of chronic disease management with monitoring and self-management assistance for physiological, lifestyle and psychological risk factors for high-risk patients with co-morbid depression, diabetes or heart disease. The study will demonstrate whether nurse-led collaborative care achieves better outcomes than usual care.<br /
A virtual clinic : telemetric assessment and monitoring for rural and remote areas
This article reports the establishment of a pilot ‘virtual clinic’ in a rural region of Victoria, Australia. Using low-cost videophones that work across ordinary phone lines, together with off-the-shelf (mostly automatic) clinical tools, local volunteers have been trained to mediate a virtual consultation between simulated patients and local GPs. This system has the potential to save long trips into town by such patients since the traditional ‘home visit’ is not feasible, as well as to provide regular home monitoring for those with chronic conditions. This in turn should impact favourably on ambulance deployment, sometimes enabling patients to avoid going to hospital or allowing them to come home sooner than otherwise would be the case, and generally to offer a sense of medical security to those living in isolated regions.<br /
- …