2,525 research outputs found

    Developing a Stand Alone Sun Photometer for Ships and Buoys

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    During November and December 1995 the first Aerosol Characterization Experiment (ACE 1) was carried to characterize the aerosol physical and optical properties in the clean marine atmosphere near Tasmania in the South Pacific. As part of this effort, and with funding from this proposal, we installed a sun photometer on the R/V Discoverer and a spectro-photometer on the NOAA C-130 aircraft

    Remote Marine Aerosol: A Characterization of Physical, Chemical and Optical Properties and their Relation to Radiative Transfer in the Troposphere

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    Our research effort is focused on improving our understanding of aerosol properties needed for optical models for remote marine regions. This includes in-situ and vertical column optical closure and involves a redundancy of approaches to measure and model optical properties that must be self consistent. The model is based upon measured in-situ aerosol properties and will be tested and constrained by the vertically measured spectral differential optical depth of the marine boundary layer, MBL. Both measured and modeled column optical properties for the boundary layer, when added to the free-troposphere and stratospheric optical depth, will be used to establish spectral optical depth over the entire atmospheric column for comparison to and validation of satellite derived radiances (AVHRR)

    Vibration Isolation Design for the Micro-X Rocket Payload

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    Micro-X is a NASA-funded, sounding rocket-borne X-ray imaging spectrometer that will allow high precision measurements of velocity structure, ionization state and elemental composition of extended astrophysical systems. One of the biggest challenges in payload design is to maintain the temperature of the detectors during launch. There are several vibration damping stages to prevent energy transmission from the rocket skin to the detector stage, which causes heating during launch. Each stage should be more rigid than the outer stages to achieve vibrational isolation. We describe a major design effort to tune the resonance frequencies of these vibration isolation stages to reduce heating problems prior to the projected launch in the summer of 2014.Comment: 6 pages, 7 figures, LTD15 Conference Proceeding

    The Allocation of a Shared Resource Within an Organization

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    Many resources such as supercomputers, legal advisors, and university classrooms are shared by many members of an organization. When the supply of shared resources is limited, conflict usually results between contending demanders. If these conflicts can be adequately resolved, then value is created for the organization. In this paper we use the methodology of applied mechanism design to examine alternative processes for the resolution of such conflicts for a particular class of scheduling problems. We construct a laboratory environment, within which we evaluate the outcomes of various allocation mechanisms. In particular, we are able to measure efficiency, the value attained by the resulting allocations as a percentage of the maximum possible value. Our choice of environment and parameters is guided by a specific application, the allocation of time on NASA's Deep Space Network, but the results also provide insights relevant to other scheduling and allocation applications. We find (1) experienced user committees using decision support algorithms produce reasonably efficient allocations in lower conflict situations but perform badly when there is a high level of conflict between demanders, (2) there is a mechanism, called the Adaptive User Selection Mechanism (AUSM) which charges users for time, which yields high efficiencies in high conflict situations but because of the prices paid, the net surplus available to the users is less than that resulting from the inefficient user committee (a reason why users may not appreciate "market solutions" to organization problems) and (3) there is a modification of AUSM in which tokens, or internal money, replaces real money, which results in highly efficient allocations without extracting any of the users' surplus. Although the distribution of surplus is still an issue, the significant increase in efficiency provides users with a strong incentive to replace inefficient user committees with the more efficient AUSM

    A public health approach to palliative care in the response to drug resistant TB: an ethnographic study in Bengaluru, India.

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    BACKGROUND: The treatment of Multidrug-Resistant Tuberculosis represents one of the most significant challenges to global health. Despite guidance on improving treatment outcomes, there is little focus on how to support individuals in their suffering. Palliative care is therefore proposed as a necessary component in the global strategy to fight Tuberculosis. We aim to describe the informal resources and networks available to persons affected by Multidrug-Resistant Tuberculosis, how they are accessed and how they are integrated into everyday lives. METHODS: In-depth ethnographic research was conducted in Bengaluru, India. Informal interactions and observations were recorded across a range of palliative care and tuberculosis treatment providers over a month-long period. In addition, ten individuals with Multidrug-Resistant Tuberculosis were asked for in-depth interviews, and five agreed. RESULTS: Multidrug-Resistant Tuberculosis caused a dynamic chain of events that transgress through physical and psychological domains to cause human suffering. Participants utilised support from their family and friends to build a network of care that was of therapeutic benefit. Informal care networks were similar to the holistic model of care practice by specialist palliative care services and represent an underused resource with enormous potential. CONCLUSION: Patient suffering is poorly addressed in current Tuberculosis treatment programmes. A community-based palliative care approach may extend peoples' support networks, helping to alleviate suffering. Further research on existing support structures and integration of these services into Tuberculosis control programmes is required

    Calcium\u27s Role as Nuanced Modulator of Cellular Physiology in the Brain

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    Neuroscientists studying normal brain aging, spinal cord injury, Alzheimer’s disease (AD) and other neurodegenerative diseases have focused considerable effort on carefully characterizing intracellular perturbations in calcium dynamics or levels. At the cellular level, calcium is known for controlling life and death and orchestrating most events in between. For many years, intracellular calcium has been recognized as an essential ion associated with nearly all cellular functions from cell growth to degeneration. Often the emphasis is on the negative impact of calcium dysregulation and the typical worse-case-scenario leading inevitably to cell death. However, even high amplitude calcium transients, when executed acutely can alter neuronal communication and synaptic strength in positive ways, without necessarily killing neurons. Here, we focus on the evidence that calcium has a subtle and distinctive role in shaping and controlling synaptic events that underpin neuronal communication and that these subtle changes in aging or AD may contribute to cognitive decline. We emphasize that calcium imaging in dendritic components is ultimately necessary to directly test for the presence of age- or disease-associated alterations during periods of synaptic activation

    Uveitis Therapy With Shark Variable Novel Antigen Receptor Domains Targeting Tumor Necrosis Factor Alpha or Inducible T-Cell Costimulatory Ligand

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    Acknowledgments Supported by an unrestricted departmental grant from Research to Prevent Blindness (New York, NY), NEI K08EY023998 (KLP), P30-EY001730 (RVG; Bethesda, MD), by a grant from Elasmogen Limited (RVG), and with support from the Mark J. Daily, MD Research Fund (RVG, KLP).Peer reviewedPublisher PD
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