Performance Measurement Under Increasing Environmental Uncertainty In The Context of Interval Type-2 Fuzzy Logic Based Robotic Sailing

Performance measurement of robotic controllers based on fuzzy logic, operating under uncertainty, is a subject area which has been somewhat ignored in the current literature. In this paper standard measures such as RMSE are shown to be inappropriate for use under conditions where the environmental uncertainty changes significantly between experiments. An overview of current methods which have been applied by other authors is presented, followed by a design of a more sophisticated method of comparison. This method is then applied to a robotic control problem to observe its outcome compared with a single measure. Results show that the technique described provides a more robust method of performance comparison than less complex methods allowing better comparisons to be drawn.Comment: International Conference on Fuzzy Systems 2013 (Fuzz-IEEE 2013

A comparison of non-stationary, type-2 and dual surface fuzzy control

Type-1 fuzzy logic has frequently been used in control systems. However this method is sometimes shown to be too restrictive and unable to adapt in the presence of uncertainty. In this paper we compare type-1 fuzzy control with several other fuzzy approaches under a range of uncertain conditions. Interval type-2 and non-stationary fuzzy controllers are compared, along with ‘dual surface’ type-2 control, named due to utilising both the lower and upper values produced from standard interval type-2 systems. We tune a type-1 controller, then derive the membership functions and footprints of uncertainty from the type-1 system and evaluate them using a simulated autonomous sailing problem with varying amounts of environmental uncertainty. We show that while these more sophisticated controllers can produce better performance than the type-1 controller, this is not guaranteed and that selection of Footprint of Uncertainty (FOU) size has a large effect on this relative performance

Performance measurement under increasing environmental uncertainty in the context of interval type-2 fuzzy logic based robotic sailing

Performance measurement of robotic controllers based on fuzzy logic, operating under uncertainty, is a subject area which has been somewhat ignored in the current literature. In this paper standard measures such as RMSE are shown to be inappropriate for use under conditions where the environmental uncertainty changes significantly between experiments. An overview of current methods which have been applied by other authors is presented, followed by a design of a more sophisticated method of comparison. This method is then applied to a robotic control problem to observe its outcome compared with a single measure. Results show that the technique described provides a more robust method of performance comparison than less complex methods allowing better comparisons to be drawn

The hypothetical consent objection to anti-natalism

Abstract: A very common but untested assumption is that potential children would consent to be exposed to the harms of existence in order to experience its benefits (if it were possible for us to ask and for them to respond). And so, would-be parents might appeal to the following view: Procreation is all-things-considered permissible, as it is morally acceptable for one to knowingly harm an unconsenting patient if one has good reasons for assuming her hypothetical consent—and procreators can indeed reasonably rely on some notion of hypothetical consent. I argue that this view is in error. My argument appeals to a consent-based version of anti-natalism advanced by Seana Valentine Shiffrin. Anti-natalism is the view that it is (almost) always wrong to bring people (and perhaps all sentient beings) into existence. While, like Shiffrin, I stop short of advocating a thoroughgoing anti-natalism, I nevertheless argue that procreators cannot appeal to hypothetical consent to justify exposing children to the harms of existence. I end by suggesting a more promising route by which this justification might be achieved

Plasmodium falciparum FIKK Kinase Members Target Distinct Components of the Erythrocyte Membrane

BACKGROUND: Modulation of infected host cells by intracellular pathogens is a prerequisite for successful establishment of infection. In the human malaria parasite Plasmodium falciparum, potential candidates for erythrocyte remodelling include the apicomplexan-specific FIKK kinase family (20 members), several of which have been demonstrated to be transported into the erythrocyte cytoplasm via Maurer's clefts. METHODOLOGY: In the current work, we have knocked out two members of this gene family (Pf fikk7.1 and Pf fikk12), whose products are localized at the inner face of the erythrocyte membrane. Both mutant parasite lines were viable and erythrocytes infected with these parasites showed no detectable alteration in their ability to adhere in vitro to endothelial receptors such as chondroitin sulfate A and CD36. However, we observed sizeable decreases in the rigidity of infected erythrocytes in both knockout lines. Mutant parasites were further analyzed using a phospho-proteomic approach, which revealed distinct phosphorylation profiles in ghost preparations of infected erythrocytes. Knockout parasites showed a significant reduction in the level of phosphorylation of a protein of approximately 80 kDa for FIKK12-KO in trophozoite stage and a large protein of about 300 kDa for FIKK7.1-KO in schizont stage. CONCLUSIONS: Our results suggest that FIKK members phosphorylate different membrane skeleton proteins of the infected erythrocyte in a stage-specific manner, inducing alterations in the mechanical properties of the parasite-infected red blood cell. This suggests that these host cell modifications may contribute to the parasites' survival in the circulation of the human host

Books

Human neurology The Human Central Nervous System: A Synopsis and Atlas. 3rd revised ed. Ed. by R. Nieuwenhuys, J. Voogd, C. H. R. van Huijzen. Pp. xii + 437. Illustrated. DM 85. Berlin: SpringerVerlag. 1988.Paediatric respiratory disorders Kendig's Disorders of the Respiratory Tract in Children. 5th ed. Ed. by Victor Chernick. Consulting ed. Edwin L. Kendig, jun. Pp. xxi + 1055. Philadelphia: WB Saunders. 1990.Maxillofacial imaging Maxillofacial Imaging. Ed. by A. M. Delbalso. pp. Vlll + 799. Illustrated. Kent: Harcourt Brace Jovanovich. 1990.Introduction to philosophy of medicine Philosophy of Medicine: An Introduction. Ed. by H. R. Wulff, S. A. Pedersen and R. Rosenberg. pp. xv + 222. £14,95. Oxford: Blackwell. 1990.Cataract management Management of Cataract in Primary Health Care Services. Pp. vi + 43. Illustrated. SFr. 15. Geneva: WHO. 1990.Family practice-management Family Practice Management. Ed. by G. J. and C. M. 1. Pistorius. Pp. 587. Illustrated. R99,50. Parow: Haurn/De Jager. J99O.Obstetrics and gynaecology Essential Obstetrics and Gynaecology. By E. Malcolm Symonds. pp. vi + 266. Illustrated. Edinburgh: Maskew Miller Longman.Surgical memoirs Surgical Roots and Branches. Ed. by R. Murley. Pp. x + 341. Illustrated. £18,50. Hamilton: Libriger Book Distribution. 1990.Survival in a hostile environment Staying Alive. Ed. by Ron Reid-Daly. Pp. ix + 259. Illustrated. R49,95. Rivonia: Ashami. 1990.Urolithiasis Urolithiasis: Medical and Surgical Reference. Ed. by M. 1. Resnick and C. Y. C. Pak. Pp. x + 375. Illustrated. R53,50. Kent: Harcoun Brace Jovanovich. 1990.Mental health in primary health care The Introduction of a Mental Health Component into Primary Health Care. pp. 1-59. SFr. 11,50. Geneva: WHO. 1990Tuberculosis in South Africa White Plague, Black Labor: Tuberculosis and the Political Economy of Health and Disease in South Africa. Ed. by Randall M. Packard. pp. xxii + 389. Illustrated. $40 (cloth) and$15,95 (paperback). California: University of California Press. 1989.Medical research Research in Medicine:"A Guide to Writing a Thesis in the Medical Sciences. Ed. by G. Murrell, C. Huang and H. Ellis. PP: xii + 105. Illustrated. £19,50 (hIb) £7,50 (Plb). Cambridge: Cambridge University Press. 1990

Mild motor impairment as prodromal state in amyotrophic lateral sclerosis:A new diagnostic entity

Amyotrophic lateral sclerosis, when viewed as a biological entity rather than a clinical syndrome, probably evolves along a continuum, with the initial clinically silent phase eventually evolving into clinically manifest amyotrophic lateral sclerosis. Since motor neuron degeneration is incremental and cumulative over time, it stands to reason that the clinical syndrome of amyotrophic lateral sclerosis is probably preceded by a prodromal state characterized by minor motor abnormalities that are initially insufficient to permit a diagnosis of amyotrophic lateral sclerosis. This prodromal period, however, is usually missed, given the invariably long delays between symptom onset and diagnostic evaluation. The Pre-Symptomatic Familial ALS Study, a cohort study of pre-symptomatic gene mutation carriers, offers a unique opportunity to observe what is typically unseen. Here we describe the clinical characterization of 20 pre-symptomatic mutation carriers (in SOD1, FUS and C9orf72) whose phenoconversion to clinically manifest disease has been prospectively studied. In so doing, we observed a prodromal phase of mild motor impairment in 11 of 20 phenoconverters. Among the n = 12 SOD1 A4V mutation carriers, phenoconversion was characterized by abrupt onset of weakness, with a short (1–3.5 months) prodromal period observable in a small minority (n = 3); the observable prodrome invariably involved the lower motor neuron axis. By contrast, in all n = 3 SOD1 I113T mutation carriers, diffuse lower motor neuron and upper motor neuron signs evolved insidiously during a prodromal period that extended over a period of many years; prodromal manifestations eventually coalesced into a clinical syndrome that is recognizable as amyotrophic lateral sclerosis. Similarly, in all n = 3 C9orf72 hexanucleotide repeat expansion mutation carriers, focal or multifocal manifestations of disease evolved gradually over a prodromal period of 1–2 years. Clinically manifest ALS also emerged following a prodromal period of mild motor impairment, lasting >4 years and ∼9 months, respectively, in n = 2 with other gene mutations (SOD1 L106V and FUS c.521del6). On the basis of this empirical evidence, we conclude that mild motor impairment is an observable state that precedes clinically manifest disease in three of the most common genetic forms of amyotrophic lateral sclerosis (SOD1, FUS, C9orf72), and perhaps in all genetic amyotrophic lateral sclerosis; we also propose that this might be true of non-genetic amyotrophic lateral sclerosis. As a diagnostic label, mild motor impairment provides the language to describe the indeterminate (and sometimes intermediate) transition between the unaffected state and clinically manifest amyotrophic lateral sclerosis. Recognizing mild motor impairment as a distinct clinical entity should generate fresh urgency for developing biomarkers reflecting the earliest events in the degenerative cascade, with potential to reduce the diagnostic delay and to permit earlier therapeutic intervention