2,568 research outputs found
High Power, Continuous-wave Supercontinuum Generation in Highly Nonlinear Fibers Pumped with High Order, Cascaded Raman Fiber Amplifiers
A novel method for efficient generation of high power, equalized
continuous-wave supercontinuum source in an all conventional silica fiber
architecture is demonstrated. Highly nonlinear fiber (HNLF) is pumped in its
anomalous dispersion region using a novel, high power, L-band laser. The L-band
laser encompasses a 6th order cascaded Raman amplifier which is pumped with a
high power Ytterbium doped fiber laser and amplifies a low-power, tunable
L-band seed source. The supercontinuum generated 35W of power with ~40%
efficiency. The Supercontinuum spectrum was measured to have a high degree of
flatness of better than 5 dB over 400 nm of bandwidth (1.3 - 1.7 micron,
limited by spectrum analyzer range) and a power spectral density in this region
of >50 mW/nm. The extent of the SC spectrum is estimated to be upto 2 micronComment: 6 pages, 5 figure
High Power, High Efficiency, Continuous-Wave Supercontinuum Generation using Standard Telecom Fibers
We demonstrate a simple module for octave spanning continuous-wave
supercontinuum generation using standard telecom fiber. This module can accept
any high power Ytterbium-doped fiber laser as input. The input light is
transferred into the anomalous dispersion region of the telecom fiber through a
cascade of Raman shifts. A recently proposed Raman laser architecture with
distributed feedback efficiently performs these Raman conversions. A spectrum
spanning over 1000nm(>1 octave) from 880-1900nm is demonstrated. The average
power from the supercontinuum is ~34W with a high conversion efficiency of 44%.
Input wavelength agility is demonstrated with similar supercontinua over a wide
input wavelength range.Comment: 6 pages, 5 figures, final versio
FogGIS: Fog Computing for Geospatial Big Data Analytics
Cloud Geographic Information Systems (GIS) has emerged as a tool for
analysis, processing and transmission of geospatial data. The Fog computing is
a paradigm where Fog devices help to increase throughput and reduce latency at
the edge of the client. This paper developed a Fog-based framework named Fog
GIS for mining analytics from geospatial data. We built a prototype using Intel
Edison, an embedded microprocessor. We validated the FogGIS by doing
preliminary analysis. including compression, and overlay analysis. Results
showed that Fog computing hold a great promise for analysis of geospatial data.
We used several open source compression techniques for reducing the
transmission to the cloud.Comment: 6 pages, 4 figures, 1 table, 3rd IEEE Uttar Pradesh Section
International Conference on Electrical, Computer and Electronics (09-11
December, 2016) Indian Institute of Technology (Banaras Hindu University)
Varanasi, Indi
Alveolar macrophages and Toll-like receptor 4 mediate ventilated lung ischemia reperfusion injury in mice.
BackgroundIschemia-reperfusion (I-R) injury is a sterile inflammatory process that is commonly associated with diverse clinical situations such as hemorrhage followed by resuscitation, transient embolic events, and organ transplantation. I-R injury can induce lung dysfunction whether the I-R occurs in the lung or in a remote organ. Recently, evidence has emerged that receptors and pathways of the innate immune system are involved in recognizing sterile inflammation and overlap considerably with those involved in the recognition of and response to pathogens.MethodsThe authors used a mouse surgical model of transient unilateral left pulmonary artery occlusion without bronchial involvement to create ventilated lung I-R injury. In addition, they mimicked nutritional I-R injury in vitro by transiently depriving cells of all nutrients.ResultsCompared with sham-operated mice, mice subjected to ventilated lung I-R injury had up-regulated lung expression of inflammatory mediator messenger RNA for interleukin-1β, interleukin-6, and chemokine (C-X-C motif) ligand-1 and -2, paralleled by histologic evidence of lung neutrophil recruitment and increased plasma concentrations of interleukin-1β, interleukin-6, and high-mobility group protein B1 proteins. This inflammatory response to I-R required toll-like receptor-4 (TLR4). In addition, the authors demonstrated in vitro cooperativity and cross-talk between human macrophages and endothelial cells, resulting in augmented inflammatory responses to I-R. Remarkably, the authors found that selective depletion of alveolar macrophages rendered mice resistant to ventilated lung I-R injury.ConclusionsThe data reveal that alveolar macrophages and the pattern recognition receptor toll-like receptor-4 are involved in the generation of the early inflammatory response to lung I-R injury
Investing in breastfeeding – the world breastfeeding costing initiative
BACKGROUND Despite scientific evidence substantiating the importance of breastfeeding in child survival and development and its economic benefits, assessments show gaps in many countries' implementation of the 2003 WHO and UNICEF Global Strategy for Infant and Young Child Feeding (Global Strategy). Optimal breastfeeding is a particular example: initiation of breastfeeding within the first hour of birth, exclusive breastfeeding for the first six months; and continued breastfeeding for two years or more, together with safe, adequate, appropriate, responsive complementary feeding starting in the sixth month. While the understanding of "optimal" may vary among countries, there is a need for governments to facilitate an enabling environment for women to achieve optimal breastfeeding. Lack of financial resources for key programs is a major impediment, making economic perspectives important for implementation. Globally, while achieving optimal breastfeeding could prevent more than 800,000 under five deaths annually, in 2013, US17.5 billion ($130 per live birth). The major recurring cost is maternity entitlements. CONCLUSIONS WBCi is a policy advocacy initiative to encourage integrated actions that enable breastfeeding. WBCi will help countries plan and prioritize actions and budget them accurately. International agencies and donors can also use the tool to calculate or track investments in breastfeeding.The project was possible
through financial support from SAFANSI (South Asia Food and Nutrition
Security Initiative) project and a contribution by DFID (Department for
International Development) and AusAID (Australian Agency for International
Development)
N-Arachidonoyl Dopamine Modulates Acute Systemic Inflammation via Nonhematopoietic TRPV1.
N-Arachidonoyl dopamine (NADA) is an endogenous lipid that potently activates the transient receptor potential vanilloid 1 (TRPV1), which mediates pain and thermosensation. NADA is also an agonist of cannabinoid receptors 1 and 2. We have reported that NADA reduces the activation of cultured human endothelial cells by LPS and TNF-α. Thus far, in vivo studies using NADA have focused on its neurologic and behavioral roles. In this article, we show that NADA potently decreases in vivo systemic inflammatory responses and levels of the coagulation intermediary plasminogen activator inhibitor 1 in three mouse models of inflammation: LPS, bacterial lipopeptide, and polymicrobial intra-abdominal sepsis. We also found that the administration of NADA increases survival in endotoxemic mice. Additionally, NADA reduces blood levels of the neuropeptide calcitonin gene-related peptide but increases the neuropeptide substance P in LPS-treated mice. We demonstrate that the anti-inflammatory effects of NADA are mediated by TRPV1 expressed by nonhematopoietic cells and provide data suggesting that neuronal TRPV1 may mediate NADA's anti-inflammatory effects. These results indicate that NADA has novel TRPV1-dependent anti-inflammatory properties and suggest that the endovanilloid system might be targeted therapeutically in acute inflammation
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