Summary of the digital adaptive filter, digital polynomial filter and specification set control techniques applied to large launch vehicles

Digital polynomial and adaptive feedback control system techniques for large launch vehicle guidance, stability, and contro

Continuation of theoretical and experimental research on digital adaptive control system, 16 September 1966 - 16 February 1967

Digital adaptive control syste

Glutamate receptors in nucleus accumbens mediate regionally selective increases in cortical acetylcholine release

The basal forebrain cortical cholinergic system (BFCS) is critical for the regulation of attentional information processing. BFCS activity is regulated by several cortical and subcortical structures, including the nucleus accumbens (NAC) and prefrontal cortex (PFC). GABAergic projection neurons from NAC to basal forebrain are modulated by Glu receptors within NAC. We previously reported that intra-NAC perfusions of NMDA or its antagonist CPP stimulate ACh release in PFC. In this experiment we determined whether this trans-synaptic modulation of cortical ACh release is evident in multi-sensory associational areas like the posterior parietal cortex (PPC). Artificial cerebrospinal fluid (aCSF, control), NMDA (250 or 400 ΜM), or CPP (200 or 400 ΜM) were perfused into the NAC shell and ACh was measured in the ipsilateral PPC. Amphetamine (2.0 mg/kg, i.p), was systemically administered as a positive control in a fourth session, since it also stimulates cortical ACh release but via mechanisms known to not necessitate transmission within the NAC. Neither NMDA nor CPP increased ACh efflux in the PPC, yet both drugs increased ACh release in PFC, suggesting that NMDA receptor modulation in the NAC increases ACh in the cortex in a regionally-specific manner. Systemic amphetamine administration significantly increased (100–200%) ACh in the PPC, suggesting that levels of ACh in the PPC can be increased following certain pharmacological manipulations. The cortical region-specific modulation of ACh by NAC may underlie the linkage of motivational information with top-down controls of attention as well as guide appropriate motor output following exposure to salient and behaviorally relevant stimuli. Synapse 61:115–123, 2007. © 2006 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55892/1/20354_ftp.pd

Control techniques for large launch vehicles Final report, Jul. 1964 - Sep. 1965

Fuel sloshing and rigid body oscillations in large rocket booster control during launchin

Block diagonal dominance for systems of nonlinear equations with application to load flow calculations in power systems

AbstractThe concept of a pointwise strict (or Ω) diagonally dominant nonlinear function, first introduced by Moré, is generalized to the blockwise case. A sufficient condition is obtained for the convergence of underrelaxed block Jacobi and block Gauss– Seidel iterations for a nonlinear system of equations in terms of the strict (or Ω) diagonal dominance of an associated matrix. A new formulation for the determination of the steady-state load flow in lossless electric power systems is described and it is shown that this formulation leads to the solution of a system of quadratic equations in the unknown (complex-valued) voltages. Under suitable assumptions on the power system the sufficient condition is satisfied. Numerical examples, consisting of an illustrative three bus system and a realistic thirty bus system, are presented. Results of our block Gauss–Seidel iteration are compared with those of Newton–Raphson iteration

Measurement issues when assessing quality of life outcomes for different types of hernia mesh repair

INTRODUCTION: The NHS is required to collect data from patient reported outcome measures (PROMs) for inguinal hernia surgery. We explored the use of one such measure, the Carolinas Comfort Scale(®) (CCS), to compare long-term outcomes for patients who received two different types of mesh. The CCS questionnaire asks about mesh sensation, pain and movement limitations, and combines the answers into a total score. PATIENTS AND METHODS: A total of 684 patients were treated between January 2007 and August 2008 and were followed up in November 2009. RESULTS: Data on 215 patients who met the inclusion criteria were available (96 patients who received Surgipro™ mesh and 119 who received Parietene™ Progrip™ mesh). Recurrence rates were similar in the Surgipro™ group (2/96, 2.1%) and Progrip™ group (3/118, 2.5%) (Fisher's exact test = 1.0). Chronic pain occurred less frequently in the Surgipro™ group (11/95, 11.6%) than in the Progrip™ group (22/118, 18.6%) (p<0.157). Overall, 90% of CCS total scores indicated a good outcome (scores of 10 or less out of 115). A principal component analysis of the CCS found that responses clustered into two subscales: 'mesh sensation' and 'pain+movement limitations'. The Progrip™ group had a slightly higher mesh sensation score (p<0.051) and similar pain+movement limitations scores (p<0.120). CONCLUSIONS: In this study of quality of life outcomes related to different mesh types, the CCS subscales were more sensitive to differences in outcome than the total CCS score for the whole questionnaire. Future research should consider using the CCS subscales rather than the CCS total score

Meynert's Nucleus Complex White Matter Abnormalities in Autism Spectrum Disorders: An MRI Study

Introduction: Cholinergic dysfunction has been proposed to play a role in autistic symtomatology. However, to date, its structural correlates are poorly understood. Methods: Twenty-five low-functioning, non-verbal males with Autism Spectrum Disorders (ASD) and 25 controls were enrolled in the study. All underwent MR T1-weighted 3D Structural Imaging and Diffusion Tensor Imaging. Grey and white matter components of the Meynert's Nucleus Complex were then identified on MR images, and both grey matter density and white matter mean Fractional Anisotropy in the Meynert's Nucleus region of interest were quantified for each subject. Non-verbal IQ was assessed in all subjects with ASD. Results: We showed reduced white matter Fractional Anisotropy in the bundles surrounding the Meynert's Nucleus in ASD subjects compared to controls. Fractional Anisotropy in these bundles was positively associated with non-verbal IQ, independently from whole brain white matter mean Fractional Anisotropy. ASD subjects did not show significant abnormalities in Meynert's Nucleus grey matter density. Conclusions: Our findings suggest that white matter abnormalities in the Meynert's Nucleus might be involved in the cholinergic deficits of ASD