Investigation and study of a multi-aperture antenna system final report, 1 jan. - 1 apr. 1964

Multiple aperture adaptive antenna system for telemetry reception from remote space vehicle

Influences of Neural Pathway Integrity on Children's Response to Reading Instruction

As the education field moves toward using responsiveness to intervention to identify students with disabilities, an important question is the degree to which this classification can be connected to a student's neurobiological characteristics. A few functional neuroimaging studies have reported a relationship between activation and response to instruction; however, whether a similar correlation exists with white matter (WM) is not clear. To investigate this issue, we acquired high angular resolution diffusion images from a group of first grade children who differed in their levels of responsiveness to a year-long reading intervention. Using probabilistic tractography, we calculated the strength of WM connections among nine cortical regions of interest and correlated these estimates with participants’ scores on four standardized reading measures. We found eight significant correlations, four of which were connections between the insular cortex and angular gyrus. In each of the correlations, a relationship with children's response to intervention was evident

Controlling Light Through Optical Disordered Media : Transmission Matrix Approach

We experimentally measure the monochromatic transmission matrix (TM) of an optical multiple scattering medium using a spatial light modulator together with a phase-shifting interferometry measurement method. The TM contains all information needed to shape the scattered output field at will or to detect an image through the medium. We confront theory and experiment for these applications and we study the effect of noise on the reconstruction method. We also extracted from the TM informations about the statistical properties of the medium and the light transport whitin it. In particular, we are able to isolate the contributions of the Memory Effect (ME) and measure its attenuation length

Separable Neural Components in the Processing of Black and White Faces

In a study of the neural components of automatic and controlled social evaluation, White participants viewed Black and White faces during event-related functional magnetic resonance imaging. When the faces were presented for 30 ms, activation in the amygdala—a brain region associated with emotion—was greater for Black than for White faces. When the faces were presented for 525 ms, this difference was significantly reduced, and regions of frontal cortex associated with control and regulation showed greater activation for Black than White faces. Furthermore, greater race bias on an indirect behavioral measure was correlated with greater difference in amygdala activation between Black and White faces, and frontal activity predicted a reduction in Black-White differences in amygdala activity from the 30-ms to the 525-ms condition. These results provide evidence for neural distinctions between automatic and more controlled processing of social groups, and suggest that controlled processes may modulate automatic evaluation.Psycholog

Methods for Fine Scale Functional Imaging of Tactile Motion in Human and Nonhuman Primates

In the visual and auditory systems specialized neural pathways use motion cues to track object motion and self-motion, and use differential motion cues for figure-ground segregation. To examine the neural circuits that encode motion in the somatosensory system, we have developed neuroimaging methods to study motion processing in human and nonhuman primates. We have implemented stimulus presentation paradigms to examine neural encoding of apparent motion percepts. These paradigms are designed to be compatible with fMRI, optical imaging, and electrophysiological methods, thereby permitting direct comparison of data derived across neurofunctional scales. An additional motivation for using a common tactile motion stimulation paradigm is to bridge two disparate bodies of work, that derived from neuroimaging studies in humans and another from neuroimaging, neurophysiological and neuroanatomical studies in monkeys. Here, we demonstrate that such an approach through the use of optical imaging and 9.4 Tesla fMRI experiments in monkeys, and 7 Tesla fMRI experiments in humans is effective in revealing neural regions activated by tactile motion stimuli. These methods span spatial scales capable of detecting 100 μm sized domains to those that would reveal global whole brain circuits. Armed with such capabilities, our long-term goals are to identify directionally selective areas and directionally se-lective functional domains and understand the global pathways within which they reside. Such knowledge would have great impact on our thinking regarding not only tactile motion processing, but also general strategies underlying somatosensory cortical processing

“We can all just get on a bus and go” : Rethinking independent mobility in the context of the universal provision of free bus travel to young Londoners

This paper uses qualitative data from interviews with 118 young Londoners (age 12-18) to examine how the universal provision of free bus travel has affected young people’s independent mobility. Drawing on Sen’s ‘capabilities approach’, we argue that free bus travel enhanced young Londoners’ capability to shape their daily mobility, both directly by increasing financial access and indirectly by facilitating the acquisition of the necessary skills, travelling companions and confidence. These capabilities in turn extended both opportunity freedoms (e.g. facilitating non-“necessary” recreational and social trips) and process freedoms (e.g. feeling more independent by decreasing reliance on parents). Moreover, the universal nature of the entitlement rendered buses a socially inclusive way for groups to travel and spend time together, thereby enhancing group-level capabilities. We believe this attention to individual and group capabilities for self-determination provides the basis for a broader and more child-centred view of ‘independent mobility’ than the typical research focus upon ‘travelling without an adult’ and acquiring parental permissions.Peer reviewe

Effective low-cost pediatric vision screening by naive nonophthalmic examiners using the 'Arclight' device

Purpose: To explore whether a low-cost ophthalmoscope (Arclight) can be used by naive nonophthalmic examiners to effectively screen for pediatric eye disease. Methods: Fifty-four children (108 eyes) were examined by five medical students using an Arclight. Gold standard examination was performed by an ophthalmologist using a slit lamp and indirect ophthalmoscope. Examinations performed included ophthalmoscopy of the optic disc, estimation of the cup-to-disc ratio (CDR), corneal light reflex test (CRT), Bruckner’s reflex test (BRT), and evaluation of refractive error. We determined the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the nonophthalmologist’s Arclight exam compared to the gold standard findings of comprehensive evaluation by pediatric ophthalmologists. Results: Using the Arclight, the optic nerve exam was successfully completed in 65% of patients. CDRs above and below 0.5 could be determined with 66.7% sensitivity and 84.4% specificity. Arclight CRT measurements were significant (P < .00001) predictors of strabismus, with 80% sensitivity, 95.1%, specificity, 80% PPV, and 95.1% NPV. BRT was not a significant predictor of amblyopia, with a 34.6% sensitivity, 85.7% specificity, 69.2% PPV, and 58.5% NPV. Refractive error was estimated with a success rate of 81% for emmetropia, 38% for myopia, and 21% for hyperopia. The Arclight ease-of-use was rated on average as 4.4 (SD = 0.9) on a scale of 1 to 5, with 1 being the hardest and 5 being the easiest. Conclusions: Our study shows the Arclight as an affordable and effective alternative to the traditional ophthalmoscope for assessing eye disease in children. This device can improve eye health services in under-resourced regions.Peer reviewe

Hydrodynamic suppression of soot emissions in laminar diffusion flames

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77139/1/AIAA-23984-264.pd

A retrospective study on the impact of comorbid depression or anxiety on healthcare resource use and costs among diabetic neuropathy patients

<p>Abstract</p> <p>Background</p> <p>Diabetic neuropathy (DN) is a common complication of diabetes that has significant economic burden, especially for patients with comorbid depression or anxiety. This study examines and quantifies factors associated with healthcare costs among patients diagnosed with diabetic neuropathy (DN) with or without a comorbid diagnosis of depression or anxiety (DA) using retrospective administrative claims data. No study has examined the differences in economic outcomes depending on the presence of comorbid DA disorders.</p> <p>Methods</p> <p>Over-age-18 individuals with 1+ diagnosis of DN in 2005 were selected. The first observed DN claim was considered the "index date." All individuals had a 12-month pre-index and follow-up period. For both under-age-65 commercially insured and over-age-65 individuals with employer-sponsored Medicare supplemental insurance, we constructed 2 subgroups for individuals with DA (DN-DA) or without (DN-only). Patients' clinical characteristics over pre-index period were compared. Multivariate regressions were performed to assess whether DN-DA patients had higher utilization of healthcare resources and costs than DN-only patients, controlling for demographic and clinical characteristics.</p> <p>Results</p> <p>We identified 16,831 DN-only and 1,699 DN-DA patients in the Medicare supplemental cohort, as well as 17,205 and 3,105 in the commercially insured. DN-DA patients had higher prevalence of diabetes-related comorbidities for cardiovascular disease, cerebrovascular/peripheral vascular disease, nephropathy, obesity, and hypoglycemic events than DN-only patients (all p < 0.05). Controlling for differences in demographic and clinical characteristics, DN-DA patients had $9,235 (p < 0.05) higher total healthcare costs than patients with DN-only among those with Medicare supplemental coverage ($26,718 vs. $17,483), and$10,389 (p < 0.05) more total costs among commercially insured ($29,775 vs.$19,386). Factors associated with increased costs included insurance type, geographical region, diabetes-related comorbidities, and insulin therapy.</p> <p>Conclusion</p> <p>These findings indicate that the healthcare costs were significantly higher for DN patients with depression or anxiety relative to those without such comorbid disorders.</p