923 research outputs found

    Challenges of poor surface water drainage and wastewater management in refugee camps

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    Since refugee camps are meant to be temporary and setting them up usually require urgency, little attention has been given to provision of surface water drainage and to a lesser extent wastewater management. As the population of refugees in these camps continues to grow, the effectiveness of drainage infrastructure continues to diminish. In addition, availability of sufficient safe drinking water and wastewater management have become difficult in the refugee camps across the world. The present situation in refugee camps across the world, such as flooding and outbreak of water-related diseases in South Sudan refugee camps, has made the need for sustainable approach to solving the problems to be very urgent. One sustainable way of solving the problems of flooding and outbreak of diseases in refugee camps is to provide effective drainage and wastewater infrastructure that ensures all the wastewater are properly collected, treated and reused for various purposes such as agriculture, drinking, laundry and other relevant uses. This paper therefore presents the current state of drainage and wastewater management in two refugee camps and propose low-cost technologies for stormwater management, wastewater collection, treatment and potential reuse, suitable for these refugee camps

    Study of Eclipsing Binary and Multiple Systems in OB Associations II. The Cygnus OB Region: V443 Cyg, V456 Cyg and V2107 Cyg

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    Three presumably young eclipsing binary systems in the direction of the Cygnus OB1, OB3 and OB9 associations are studied. Component spectra are reconstructed and their orbits are determined using light curves and spectra disentangling techniques. V443 Cyg and V456 Cyg have circular orbits, while the light curve of V2107\,Cyg imposes a slightly eccentric orbit (e=0.045±0.03)e=0.045\pm0.03). V443 Cyg harbours F-type stars, and not young early-A stars as previously suggested in the literature based on photometry solely. It appears to be situated in the foreground (distance 0.6±0.20.6\pm0.2 kpc) of the young stellar populations in Cygnus. V456 Cyg, at a distance of 0.50±0.030.50\pm0.03 kpc consists of a slightly metal-weak A--type and an early--F star. The age of both systems, on or very near to the main sequence, remains uncertain by an order of magnitude. V2107 Cyg is a more massive system (8.9±28.9\pm2 and 4.5±1.2M4.5\pm1.2 M_\odot) at 1.5±0.51.5\pm0.5 kpc and, also kinematically, a strong candidate-member of Cyg OB1. The more massive component is slightly evolved and appears to undergo non-radial βCep\beta Cep-type pulsations. The Doppler signal of the secondary is barely detectable. A more extensive study is important to fix masses more precisely, and an asteroseismological study would then become appropriate. Nevertheless, the position of the primary in the HR-diagram confines the age already reasonably well to 20±520\pm5 Myr, indicating for Cyg OB1 a similar extent of star formation history as established for Cyg OB2.Comment: 27 pages, including 9 figures and 6 tables, accepted for publication in Astronomical Journa

    MRI: Acquisition of Interactive Visualization Tools for Supercomputer Models

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    This project, acquiring a visualization facility (vizwall with high resolution display and high volume storage system to visualize large size data generated from diverse research activities), models polar ice sheets, oceans, atmospheric turbulent boundary layers, and geodynamics. The facility, whose main components consist of a visualization wall, a PRISM visualization server, and RAID storage disks, will be integrated to the university\u27s existing supercomputer cluster

    Cloud Host Selection using Iterative Particle-Swarm Optimization for Dynamic Container Consolidation

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    A significant portion of the energy consumption in cloud data centres can be attributed to the inefficient utilization of available resources due to the lack of dynamic resource allocation techniques such as virtual machine migration and workload consolidation strategies to better optimize the utilization of resources. We present a new method for optimizing cloud data centre management by combining virtual machine migration with workload consolidation. Our proposed Energy Efficient Particle Swarm Optimization (EE-PSO) algorithm to improve resource utilization and reduce energy consumption. We carried out experimental evaluations with the Container CloudSim toolkit to demonstrate the effectiveness of the proposed EE-PSO algorithm in terms of energy consumption, quality of service guarantees, the number of newly created VMs, and container migrations

    Tunable Room Temperature THz Sources Based on Nonlinear Mixing in a Hybrid Optical and THz Micro-Ring Resonator

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    We propose and systematically investigate a novel tunable, compact room temperature terahertz (THz) source based on difference frequency generation in a hybrid optical and THz micro-ring resonator. We describe detailed design steps of the source capable of generating THz wave in 0.5–10 THz with a tunability resolution of 0.05 THz by using high second order optical susceptibility (x(2)) in crystals and polymers. In order to enhance THz generation compared to bulk nonlinear material, we employ a nonlinear optical micro-ring resonator with high-Q resonant modes for infrared input waves. Another ring oscillator with the same outer radius underneath the nonlinear ring with an insulation of SiO2 layer supports the generated THz with resonant modes and out-couples them into a THz waveguide. The phase matching condition is satisfied by engineering both the optical and THz resonators with appropriate effective indices. We analytically estimate THz output power of the device by using practical values of susceptibility in available crystals and polymers. The proposed source can enable tunable, compact THz emitters, on-chip integrated spectrometers, inspire a broader use of THz sources and motivate many important potential THz applications in different fields

    Induced hypotension for functional endoscopic sinus surgery: comparison between dexmedetomidine and nitro-glycerine

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    Background: Functional endoscopic sinus surgery (FESS) is a minimally invasive technique used to restore sinus ventilation and normal function by opening sinus air cells and ostia. FESS requires bloodless field, several techniques and drugs have been used in the past for achieving controlled hypotension such as nitroglycerine, esmolol, remifentanil, dexmedetomidine, isoflurane, propofol. Therefore, this study was conducted to compare between dexmedetomidine and nitroglycerine for controlled hypotension for FESS. Primary aim to compare quality of surgical field using average category scale and surgeon satisfaction and secondary aim to compare arterial pressure and heart rate changes between dexmedetomidine and nitroglycerine when used to induce hypotension.Methods: This study was conducted in 40 consenting adult patients posted for FESS and were randomly divided into two groups, group D received dexmedetomidine 1 mcg/kg and group N received nitroglycerine 0.5 mcg/kg/min, both infusions started 10 min after induction. Parameters such as quality of surgical field by average category scale, heart rate and mean arterial pressure (MAP) recorded every 10 minutes.Results: Dexmedetomidine and nitroglycerine both had comparable quality of surgical field. ACS grading of 1 or 2 were found among both the groups. Dexmedetomidine group had better mean arterial pressure at 10th, 20th, 30th, 40th, 50th, 60th and 70th min and heart rate at 10th, 20th, 30th, 40th, 50th, 60th and 70th min when compared to nitroglycerine group.Conclusions: Dexmedetomidine and nitroglycerine both were found to be safe to use for controlled hypotension in functional endoscopic sinus surgeries

    Quality of weight loss advice on internet forums.

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    BACKGROUND: Adults use the Internet for weight loss information, sometimes by participating in discussion forums. Our purpose was to analyze the quality of advice exchanged on these forums. METHODS: This was a retrospective analysis of messages posted to 18 Internet weight loss forums during 1 month in 2006. Advice was evaluated for congruence with clinical guidelines; potential for causing harm; and subsequent correction when it was contradictory to guidelines (erroneous) or potentially harmful. Message- and forum-specific characteristics were evaluated as predictors of advice quality and self-correction. RESULTS: Of 3368 initial messages, 266 (7.9%) were requests for advice. Of 654 provisions of advice, 56 (8.6%) were erroneous and 19 of these 56 (34%) were subsequently corrected. Forty-three (6.6%) provisions of advice were harmful, and 12 of these 43 (28%) were subsequently corrected. Messages from low-activity forums (fewer messages) were more likely than those from high-activity forums to be erroneous (10.6% vs 2.4%, P \u3c .001) or harmful (8.4% vs 1.2%, P \u3c .001). In high-activity forums, 2 of 4 (50%) erroneous provisions of advice and 2 of 2 (100%) potentially harmful provisions of advice were corrected by subsequent postings. Compared with general weight loss advice, medication-related advice was more likely to be erroneous (P = .02) or harmful (P = .01). CONCLUSIONS: Most advice posted on highly active Internet weight loss forums is not erroneous or harmful. However, clinical and research strategies are needed to address the quality of medication-related advice

    Immunomodulatory function and in vivo properties of pediococcus pentosaceus OZF, a promising probiotic strain

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    Some of the important properties of probiotics are the ability to survive during gastrointestinal transit and to modulate the immune functions. The objectives of the reported study were to assess in vivo gastrointestinal survival of orally administered Pediococcus pentosaceus OZF using an animal model BALB/c mice, and to examine its effects on the immune response. Following oral administration to mice, the ability of Pediococcus pentosaceus OZF to pass and survive through the mouse gastrointestinal system was investigated by analyzing the recovery of the strain in fecal samples. Microbiological and polymerase chain reaction (PCR) methods proved that the strain OZF could overcome specific conditions in the gastrointestinal tract of mice and reach the intestine alive after ingestion. To observe the effect of oral administration on immune response, IL-6, IL-12 and IFN-γ were measured by ELISA, and the strain OZF was found to cause increases in IL-6 synthesis in regularly fed mice. However, stimulation was carried out with various concentrations of bacterial ssDNA and heat killed cells of Pediococcus pentosaceus OZF. The heat killed cells of the strain OZF were shown to produce IFN- γ independently from IL-12. On the other hand, a significant difference between control and experimental group was noticed when lipopolysaccharide, a TLR4 (toll like receptor) ligand, was used. Overall, Pediococcus pentosaceus OZF may be a valuable probiotic strain for therapeutic uses. Nevertheless, further studies on the mechanisms of immunomodulatory effect will allow for better clarification of the immune functions of this strain. © Springer-Verlag Berlin Heidelberg and the University of Milan 2012
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