Parallel machine architecture and compiler design facilities

The objective is to provide an integrated simulation environment for studying and evaluating various issues in designing parallel systems, including machine architectures, parallelizing compiler techniques, and parallel algorithms. The status of Delta project (which objective is to provide a facility to allow rapid prototyping of parallelized compilers that can target toward different machine architectures) is summarized. Included are the surveys of the program manipulation tools developed, the environmental software supporting Delta, and the compiler research projects in which Delta has played a role

Serotonin 5-HT(2A )and 5-HT(6 )receptors in the prefrontal cortex of Alzheimer and normal aging patients

BACKGROUND: It has been hypothesized that alterations of the serotonergic system contribute to neuropsychiatric symptoms in Alzheimer disease (AD). Cellular expressions of the two serotonergic receptors 5-HT(2A )and 5-HT(6 )have therefore been determined by immunohistochemistry in the prefrontal cortex of patients with AD (n=6) and normal age-matched controls (n = 7). RESULTS: In normal aging patients, 5-HT(2A )label was mainly observed in large pyramidal cells, but to a lesser extent also in small pyramidal cells and in stellate cells of cortical layers II-VI. In AD, a similar distribution was observed, but density of positive cells was significantly reduced by 33%. In aging control patients, the 5-HT(6 )receptor was expressed by pyramidal cells and occasional stellate cells, not only of layers II-V, but also of layer I, where a distinct label was observed in neurons and surrounding fibers. 5-HT(6 )receptor expression in AD patients had the same pattern, but was significantly decreased by 40%. CONCLUSION: Our results indicate that a decline in neurons expressing 5-HT(2A), but also 5-HT(6 )receptors may play a role in the etiopathology of neuropsychiatric symptoms in AD

Method of Obtaining High Resolution Intrinsic Wire Boom Damping Parameters for Multi-Body Dynamics Simulations

The goal of NASA's Magnetospheric MultiScale (MMS) mission is to understand magnetic reconnection with sensor measurements from four spinning satellites flown in a tight tetrahedron formation. Four of the six electric field sensors on each satellite are located at the end of 60- meter wire booms to increase measurement sensitivity in the spin plane and to minimize motion coupling from perturbations on the main body. A propulsion burn however, might induce boom oscillations that could impact science measurements if oscillations do not damp to values on the order of 0.1 degree in a timely fashion. Large damping time constants could also adversely affect flight dynamics and attitude control performance. In this paper, we will discuss the implementation of a high resolution method for calculating the boom's intrinsic damping, which was used in multi-body dynamics simulations. In summary, experimental data was obtained with a scaled-down boom, which was suspended as a pendulum in vacuum. Optical techniques were designed to accurately measure the natural decay of angular position and subsequently, data processing algorithms resulted in excellent spatial and temporal resolutions. This method was repeated in a parametric study for various lengths, root tensions and vacuum levels. For all data sets, regression models for damping were applied, including: nonlinear viscous, frequency-independent hysteretic, coulomb and some combination of them. Our data analysis and dynamics models have shown that the intrinsic damping for the baseline boom is insufficient, thereby forcing project management to explore mitigation strategies

Model assessment for Bayesian spatio-temporal epidemic models for complex data sets using hybrid computational methods

This project investigates the use of model assessment techniques for stochastic spatiotemporal models, with a focus on embedding classical style tests within the Bayesian framework and applying them to study real-world systems. Techniques will be investigated within the context of epidemic models. These models model the spread of a disease, for example, citrus canker, over a spatial region. We will focus on methods of choosing between different transmission kernels. The transmission kernel is a component in the model which determines how the disease spreads over space and time, and is important in choosing the right strategy for the disease, for example, culling of infected individual. The methods for model selection within this context are challenging to develop and implement. Building on recent work within the group which has focused on tests applied to residual processes, we will investigate how likelihood-based tests might be applied to latent processes in order to formulate methods that avoid the sensitivity to parameter priors suffered by purely Bayesian approaches to model comparison. In addition, we extend existing latent residual tests to detect the presence of anisotropic spatial kernels. The power of these tests will be calculated and their advantages and disadvantages investigated, both from a computational and a practical perspective as well from a theoretical perspective. These investigations will be carried out using computational statistical methods performed on simulated and real-world data sets, including the DEFRA data-set for the foot-and-mouth outbreak of 2001. Our investigations show that the likelihood-based methods are able to detect misspecification of spatial kernel, sometimes exceeding the power of existing latent residual tests. Our directional infection link residual test is shown to be able detect anisotropy in simulated data. Using hybrid computational programming techniques, our tests have been shown to scale to big data sets of 188,361 individuals, and detect mis-specification of kernel in an existing analysis of the data.EPSRC fundin

A scanning electron microscopic study of the marmoset palate and periodontium microvasculature using corrosion casts

Thesis (M.D.S.) -- University of Adelaide, Dept. of Dentistry, 198

Effects of Perinatal Exposure to Ketamine on the Developing Brain

Initially used as an analgesic and anesthetic, ketamine has unfortunately been abused as a popular recreational party drug due to its psychotropic effects. Over the last decade, ketamine has also emerged as an effective rapid-onset anti-depressant. The increasingly widespread use and misuse of the drug in infants and pregnant women has posed a concern about the neurotoxicity of ketamine to the immature brains of developing fetuses and children. In this review, we summarize recent research findings on major possible mechanisms of perinatal ketamine-induced neurotoxicity. We also briefly summarize the neuroprotective effects of ketamine in the presence of noxious stimuli. Future actions include implementation of more drug abuse education and prevention campaigns to raise the public’s awareness of the harmful effects of ketamine abuse; further investigations to justify the clinical use of ketamine as analgesic, anesthetic and anti-depressant; and further studies to develop alternatives to ketamine or treatments that can alleviate the detrimental effects of ketamine use, especially in infants and pregnant women

Responses of Astrocytes in Culture After Low Dose Laser Irradiation

The effect of Helium-Neon low dose laser on astrocytes was investigated in cultures of isolated astrocytes from albino neonatal rats. The laser appeared to inhibit the growth of astrocytes as exemplified by the smaller sizes of the cells and the decreased leucine uptake in each cell after treatment. Temporary decrease in the number of mitoses was also observed, but this trend was reversed soon after. Electron microscopic studies revealed an increase in buddings from cell bodies and processes (branches) after irradiation

Neoplasms of the vagina following cervical carcinoma

Neoplasm in the vagina which occurs following treatment of cervical carcinoma could represent a separate primary neoplasm, a "field" response to a common carcinogen, or be due to neoplastic transformation of tissue from previous radiation treatment. Fifty patients with a second neoplasm in the vagina were identified: 17 following total hysterectomy for carcinoma in situ of cervix; 4 following radical hysterectomy; and 29 following radiotherapy for invasive cervical carcinoma. Their clinical features, diagnosis, and treatment modalities are presented. Since vaginal neoplasm may occur long after treatment of the initial cervical carcinoma especially after previous radiotherapy, life-long follow-up of all patients with cervical carcinoma is mandatory.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23906/1/0000149.pd

Electron dynamics in topological insulator based semiconductor-metal interfaces (topological p-n interface based on Bi2Se3 class)

Single-Dirac-cone topological insulators (TI) are the first experimentally discovered class of three dimensional topologically ordered electronic systems, and feature robust, massless spin-helical conducting surface states that appear at any interface between a topological insulator and normal matter that lacks the topological insulator ordering. This topologically defined surface environment has been theoretically identified as a promising platform for observing a wide range of new physical phenomena, and possesses ideal properties for advanced electronics such as spin-polarized conductivity and suppressed scattering. A key missing step in enabling these applications is to understand how topologically ordered electrons respond to the interfaces and surface structures that constitute a device. Here we explore this question by using the surface deposition of cathode (Cu/In/Fe) and anode materials (NO$_2$) and control of bulk doping in Bi$_2$Se$_3$ from P-type to N-type charge transport regimes to generate a range of topological insulator interface scenarios that are fundamental to device development. The interplay of conventional semiconductor junction physics and three dimensional topological electronic order is observed to generate novel junction behaviors that go beyond the doped-insulator paradigm of conventional semiconductor devices and greatly alter the known spin-orbit interface phenomenon of Rashba splitting. Our measurements for the first time reveal new classes of diode-like configurations that can create a gap in the interface electron density near a topological Dirac point and systematically modify the topological surface state Dirac velocity, allowing far reaching control of spin-textured helical Dirac electrons inside the interface and creating advantages for TI superconductors as a Majorana fermion platform over spin-orbit semiconductors.Comment: 14 pages, 4 Figure