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Comprehensive test ban treaty international monitoring system security threats and proposed security attributes
To monitor compliance with a Comprehensive Test Ban Treaty (CTBT), a sensing network, referred to as the International Monitoring System (IMS), is being deployed. Success of the IMS depends on both its ability to preform its function and the international community`s confidence in the system. To ensure these goals, steps must be taken to secure the system against attacks that would undermine it; however, it is not clear that consensus exists with respect to the security requirements that should be levied on the IMS design. In addition, CTBT has not clearly articulated what threats it wishes to address. This paper proposes four system-level threats that should drive IMS design considerations, identifies potential threat agents, and collects into one place the security requirements that have been suggested by various elements of the IMS community. For each such requirement, issues associated with the requirement are identified and rationale for the requirement is discussed
The development and application of two-time-scale turbulence models for non-equilibrium flows
The reliable prediction of turbulent non-equilibrium flows is of high academic and industrial interest in several engineering fields. Most turbulent flows are often predicted using single-time-scale Reynolds-Averaged-Navier-Stokes (RANS) turbulence models which assume the flows can be modelled through a single time or length scale which is an admittedly incorrect assumption. Therefore they are not expected to capture the lag in the response of the turbulence in non-equilibrium flows. In attempts to improve prediction of these flows, by taking into consideration some features of the turbulent kinetic energy spectrum, the multiple-time-scale models arose. A number of two-scale models have been proposed, but so far their use has been rather limited.This work thus focusses on the development of two-time-scale approaches. Two two-time-scale linear-eddy-viscosity models, referred to as NT1 and NT2 models, have been developed and the initial stages of the development of two-time-scale non-linear-eddy-viscosity models are also reported. The models' coefficients have been determined through asymptotic analysis of decaying grid turbulence, homogeneous shear flows and the flow in a boundary layer in local equilibrium. Three other important features of these models are that there is consistent partition of the large and the small scales for all above limiting cases, model sensitivity to the partition and production rate ratios and sensitivity of the eddy viscosity sensitive to the mean strain rates.The models developed have been tested through computations of a wide range of flows such as homogeneous shear and normally strained flows, fully developed channel flows, zero-pressure-gradient, adverse-pressure-gradient, favourable-pressure-gradient and oscillatory boundary layer flows, fully developed oscillatory and ramp up pipe flows and steady and pulsated backward-facing-step flows.The proposed NT1 and NT2 two-scale models have been shown to perform well in all test cases, being, among the benchmarked models tested, the models which best performed in the wide range of dimensionless shear values of homogeneous shear flows, the only linear-eddy-viscosity models which predicted well the turbulent kinetic energy in the normally strained cases and the only models which showed satisfactory sensitivity in predicting correctly the reattachment point in the unsteady backward facing step cases with different forcing frequencies. Although the development of the two-time-scale non-linear-eddy-viscosity models is still in progress, the interim versions proposed here have resulted in predictions of the Reynolds normal stresses similar to those of much more complex models in all test cases studied and in predictions of the turbulent kinetic energy in normally strained flows which are better than those of the other models tested in this study.EThOS - Electronic Theses Online ServiceCNPq, National Council for Scientific and Technological Development, BrazilOverseas Research Student (ORS) Scholarship, School of MACEGBUnited Kingdo
Don’t worry deer, predators are not real (no one has seen one before).
The absence of natural predators could have profound behavioral and ecological impacts. Black tail deer (BTD) on Blakely Island provide a unique opportunity to study the effects of predation as there is a multigenerational lack of predators on the island. Therefore, the current study was designed to determine if the lack of predators has a behavioral impact (e.g., vigilance) on BTD as well as forest ecology. Two Douglas Fir saplings, and either cow or wolf urine, were placed in ten locations across the island. Trail cameras recorded BTD behavior. We predicted that predator cues would influence BTD behaviors and foraging
Exploring the Nexus of Alzheimer’s Disease and Related Dementias with Cancer and Cancer Therapies
Recent population studies suggest an intriguing inverse relationship between several types of cancer and neurodegenerative diseases, including Alzheimer’s disease. Understanding the intersection of the underlying biology for these two distinct families of diseases with one another may offer novel approaches to identify new therapeutic approaches and possible opportunities to repurpose existing drug candidates. The Alzheimer’s Association and the Alzheimer’s Drug Discovery Foundation convened a one day workshop to delve into this discussion. Workshop participants outlined research focus areas, potential collaborations and partnerships for future action
Transcriptional Profiles in Olfactory Pathway-Associated Brain Regions of African Green Monkeys: Associations With Age and Alzheimer’s Disease Neuropathology
Introduction: Olfactory impairment in older individuals is associated with an increased risk of Alzheimer\u27s disease (AD). Characterization of age versus neuropathology-associated changes in the brain olfactory pathway may elucidate processes underlying early AD pathogenesis. Here, we report age versus AD neuropathology-associated differential transcription in four brain regions in the olfactory pathway of 10 female African green monkeys (vervet, Chlorocebus aethiops sabaeus), a well-described model of early AD-like neuropathology.
Methods: Transcriptional profiles were determined by microarray in the olfactory bulb (OB), piriform cortex (PC), temporal lobe white matter (WM), and inferior temporal cortex (ITC). Amyloid beta (Aβ) plaque load in parietal and temporal cortex was determined by immunohistochemistry, and concentrations of Aβ42, Aβ40, and norepinephrine in ITC were determined by enzyme-linked immuosorbent assay (ELISA). Transcriptional profiles were compared between middle-aged and old animals, and associations with AD-relevant neuropathological measures were determined.
Results: Transcriptional profiles varied by brain region and age group. Expression levels of TRO and RNU4-1 were significantly lower in all four regions in the older group. An additional 29 genes were differentially expressed by age in three of four regions. Analyses of a combined expression data set of all four regions identified 77 differentially expressed genes (DEGs) by age group. Among these DEGs, older subjects had elevated levels of CTSB , EBAG9, LAMTOR3, and MRPL17, and lower levels of COMMD10 and TYW1B. A subset of these DEGs was associated with neuropathology biomarkers. Notably, CTSB was positively correlated with Aβ plaque counts, Aβ42:Aβ40 ratios, and norepinephrine levels in all brain regions.
Discussion: These data demonstrate age differences in gene expression in olfaction-associated brain regions. Biological processes exhibiting age-related enrichment included the regulation of cell death, vascular function, mitochondrial function, and proteostasis. A subset of DEGs was specifically associated with AD phenotypes. These may represent promising targets for future mechanistic investigations and perhaps therapeutic intervention
Diagnostic performance of treadmill exercise cardiac magnetic resonance: the prospective, multicenter EXACT trial
Effects of acute adult and early-in-life bladder inflammation on bladder neuropeptides in adult female rats
Interaction between Attention and Bottom-Up Saliency Mediates the Representation of Foreground and Background in an Auditory Scene
Bottom-up (stimulus-driven) and top-down (attentional) processes interact when a complex acoustic scene is parsed. Both modulate the neural representation of the target in a manner strongly correlated with behavioral performance
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