Radiometric performance of AVIRIS: Assessment for an arid region geologic target

Data from several AVIRIS flight lines were examined to assess instrument stability and response. Both scene and in-flight calibration data were analyzed statistically. The data clearly indicates that, although the instrument output was noisy and unstable at the time of the data acquisition, valuable spectral signatures can still be extracted and analyzed. Some first order calibration corrections can be performed by forcing internal consistency within the data. AVIRIS data are delivered in band-interleaved-by-line format, but high efficiency routines were developed which access the data as either image or spectral planes and enable effective statistical and visual examination of both AVIRIS scenes and ancillary files. Two methods were used to extract spectral information from segment 4 of the Kelso Dunes flight. Both successfully identified at least three distinct spectral signatures, but neither has positively identified a specific material

Beyond static measures:A review of functional magnetic resonance spectroscopy and its potential to investigate dynamic glutamatergic abnormalities in schizophrenia

Abnormalities of the glutamate system are increasingly implicated in schizophrenia but their exact nature remains unknown. Proton magnetic resonance spectroscopy (1H-MRS), while fundamental in revealing glutamatergic alterations in schizophrenia, has, until recently, been significantly limited and thought to only provide static measures. Functional magnetic resonance spectroscopy (fMRS), which uses sequential scans for dynamic measurement of a range of brain metabolites in activated brain areas, has lately been applied to a variety of task or stimulus conditions, producing interesting insights into neurometabolite responses to neural activation. Here, we summarise the existing 1H-MRS studies of brain glutamate in schizophrenia. We then present a comprehensive review of research studies that have utilised fMRS, and lastly consider how fMRS methods might further the understanding of glutamatergic abnormalities in schizophrenia. </jats:p

Simulating Windows-Based Cyber Attacks Using Live Virtual Machine Introspection

Static memory analysis has been proven a valuable technique for digital forensics. However, the memory capture technique halts the system causing the loss of important dynamic system data. As a result, live analysis techniques have emerged to complement static analysis. In this paper, a compiled memory analysis tool for virtualization (CMAT-V) is presented as a virtual machine introspection (VMI) utility to conduct live analysis during simulated cyber attacks. CMAT-V leverages static memory dump analysis techniques to provide live system state awareness. CMAT-V parses an arbitrary memory dump from a simulated guest operating system (OS) to extract user information, network usage, active process information and registry files. Unlike some VMI applications, CMAT-V bridges the semantic gap using derivation techniques. This provides increased operating system compatibility for current and future operating systems. This research demonstrates the usefulness of CMAT-V as a situational awareness tool during simulated cyber attacks and measures the overall performance of CMAT-V

Transgluteal CT-Guided Percutaneous Renal Access for Percutaneous Nephrolithotomy in a Pelvic Horseshoe Kidney

CT-guided percutaneous renal access has been described as a safe and effective access technique in patients with complex anatomy, including ectopic kidney, retrorenal colon, spinal dysraphism, hepatomegaly, and splenomegaly. In comparison to conventional intraoperative fluoroscopic-guided access, CT imaging allows for delineation of surrounding structures that are at risk for injury during percutaneous access. However, previous reports indicate that pelvic kidneys might be inaccessible percutaneously without laparoscopic assistance. Herein, we present a novel transgluteal route to renal access for percutaneous nephrolithotomy (PCNL) in a patient with a pelvic horseshoe kidney and severe spinal deformity

Molecular clock-like evolution of human immunodeficiency virus type 1

AbstractThe molecular clock hypothesis states that the rate of nucleotide substitution per generation is constant across lineages. If generation times were equal across lineages, samples obtained at the same calendar time would have experienced the same number of generations since their common ancestor. However, if sequences are not derived from contemporaneous samples, differences in the number of generations may be misinterpreted as variation in substitution rates and hence may lead to false rejection of the molecular clock hypothesis. A recent study has called into doubt the validity of clock-like evolution for HIV-1, using molecular sequences derived from noncontemporaneous samples. However, after separating their within-individual data according to sampling time, we found that what appeared to be nonclock-like behavior could be attributed, in most cases, to noncontemporaneous sampling, with contributions also likely to derive from recombination. Natural selection alone did not appear to obscure the clock-like evolution of HIV-1