1,528 research outputs found

    Water reuse: dairy effluent treated by a hybrid anaerobic biofilm baffled reactor and its application in lettuce irrigation

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    There is a synergy between the large quantities of organics-rich effluents generated by the dairy industry and the continually increasing water needs for crop irrigation. In this sense, this study aimed at evaluating the effect of decreasing the hydraulic retention time (HRT) on the stability and efficiency of a hybrid anaerobic biofilm baffled reactor (HABBR) treating simulated fat- and salt-rich dairy wastewater, followed by its agricultural reuse. The reactor was monitored over 328 days, during which 72, 24, and 12 hours were the hydraulic detention times. After achieving steady-state, the reactor presented organic matter removal above 90% and produced biogas with 41 ± 23%, 53 ± 3%, and 64 ± 12% of methane for HRTs of 72, 24, and 12 hours, respectively. The best process performance was observed for an HRT of 24 h, and thus, a lettuce culture was irrigated with the treated effluent. The irrigation was performed in five different treatments, for which the amount of treated effluent added to tap water varied from 0 to 100%. Both the effluent and the harvested vegetables were evaluated for microbial contamination. Apart from the 75% effluent supply condition, there were no losses in leaf mass or area observed, and instead, there was an increase of these parameters for the 25 and 50% effluent supply treatment. The use of dairy effluent treated by the HABBR allowed for microbiologically safe food production. Therefore, the process offered both potential cost reduction for fertilizers, preservation of water resources, and a renewable energy source.The authors are grateful to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES for the grants to L. K. A. Santos (Finace Code 001) and to M. M. S. Alves (PVE 123/2012, process no. 23038.009805/2012-39), as well for the financial support.info:eu-repo/semantics/publishedVersio

    Oral Appliance Treatment for Obstructive Sleep Apnea: An Update

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    Oral appliances (OA) have emerged as an alternative to continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA) treatment. The most commonly used OA reduces upper airway collapse by advancing the mandible (OAm). There is a strong evidence base demonstrating OAm improve OSA in the majority of patients, including some with more severe disease. However OAm are not efficacious for all, with approximately one-third of patients experiencing no therapeutic benefit. OAm are generally well tolerated, although short-term adverse effects during acclimatization are common. Long-term dental changes do occur, but these are for the most part subclinical and do not preclude continued use. Patients often prefer OAm to gold-standard CPAP treatment. Head-to-head trials confirm CPAP is superior in reducing OSA parameters on polysomnography; however, this greater efficacy does not necessarily translate into better health outcomes in clinical practice. Comparable effectiveness of OAm and CPAP has been attributed to higher reported nightly use of OAm, suggesting that inferiority in reducing apneic events may be counteracted by greater treatment adherence. Recently, significant advances in commercially available OAm technologies have been made. Remotely controlled mandibular positioners have the potential to identify treatment responders and the level of therapeutic advancement required in single night titration polysomnography. Objective monitoring of OAm adherence using small embedded temperature sensing data loggers is now available and will enhance clinical practice and research. These technologies will further enhance efficacy and effectiveness of OAm treatment for OSA

    Myofunctional Therapy to Treat Obstructive Sleep Apnea: A Systematic Review and Meta-analysis.

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    OBJECTIVE: To systematically review the literature for articles evaluating myofunctional therapy (MT) as treatment for obstructive sleep apnea (OSA) in children and adults and to perform a meta-analysis on the polysomnographic, snoring, and sleepiness data. DATA SOURCES: Web of Science, Scopus, MEDLINE, and The Cochrane Library. REVIEW METHODS: The searches were performed through June 18, 2014. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was followed. RESULTS: Nine adult studies (120 patients) reported polysomnography, snoring, and/or sleepiness outcomes. The pre- and post-MT apneahypopnea indices (AHI) decreased from a mean ± standard deviation (M ± SD) of 24.5 ± 14.3/h to 12.3 ± 11.8/h, mean difference (MD) -14.26 [95% confidence interval (CI) -20.98, -7.54], P < 0.0001. Lowest oxygen saturations improved from 83.9 ± 6.0% to 86.6 ± 7.3%, MD 4.19 (95% CI 1.85, 6.54), P = 0.0005. Polysomnography snoring decreased from 14.05 ± 4.89% to 3.87 ± 4.12% of total sleep time, P < 0.001, and snoring decreased in all three studies reporting subjective outcomes. Epworth Sleepiness Scale decreased from 14.8 ± 3.5 to 8.2 ± 4.1. Two pediatric studies (25 patients) reported outcomes. In the first study of 14 children, the AHI decreased from 4.87 ± 3.0/h to 1.84 ± 3.2/h, P = 0.004. The second study evaluated children who were cured of OSA after adenotonsillectomy and palatal expansion, and found that 11 patients who continued MT remained cured (AHI 0.5 ± 0.4/h), whereas 13 controls had recurrent OSA (AHI 5.3 ± 1.5/h) after 4 y. CONCLUSION: Current literature demonstrates that myofunctional therapy decreases apnea-hypopnea index by approximately 50% in adults and 62% in children. Lowest oxygen saturations, snoring, and sleepiness outcomes improve in adults. Myofunctional therapy could serve as an adjunct to other obstructive sleep apnea treatments

    The Dynamics of Internet Traffic: Self-Similarity, Self-Organization, and Complex Phenomena

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    The Internet is the most complex system ever created in human history. Therefore, its dynamics and traffic unsurprisingly take on a rich variety of complex dynamics, self-organization, and other phenomena that have been researched for years. This paper is a review of the complex dynamics of Internet traffic. Departing from normal treatises, we will take a view from both the network engineering and physics perspectives showing the strengths and weaknesses as well as insights of both. In addition, many less covered phenomena such as traffic oscillations, large-scale effects of worm traffic, and comparisons of the Internet and biological models will be covered.Comment: 63 pages, 7 figures, 7 tables, submitted to Advances in Complex System

    Reanalysis of Data Taken by the CANGAROO 3.8 Meter Imaging Atmospheric Cherenkov Telescope: PSR B1706-44, SN 1006, and Vela

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    We have reanalyzed data from observations of PSR B1706-44, SN 1006, and the Vela pulsar region made with the CANGAROO 3.8 m imaging atmospheric Cherenkov telescope between 1993 and 1998 in response to the results reported for these sources by the H.E.S.S. collaboration. In our reanalysis, in which gamma-ray selection criteria have been determined exclusively using gamma-ray simulations and OFF-source data as background samples, no significant TeV gamma-ray signals have been detected from compact regions around PSR B1706-44 or within the northeast rim of SN 1006. We discuss reasons why the original analyses gave the source detections. The reanalysis did result in a TeV gamma-ray signal from the Vela pulsar region at the 4.5 sigma level using 1993, 1994, and 1995 data. The excess was located at the same position, 0.13 deg. to the southeast of the Vela pulsar, as that reported in the original analysis. We have investigated the effect of the acceptance distribution in the field of view of the 3.8 m telescope, which rapidly decreases toward the edge of the field of the camera, on the detected gamma-ray morphology. The expected excess distribution for the 3.8 m telescope has been obtained by reweighting the distribution of HESS J0835-455 measured by H.E.S.S. with the acceptance of the 3.8 m telescope. The result is morphologically comparable to the CANGAROO excess distribution, although the profile of the acceptance-reweighted H.E.S.S. distribution is more diffuse than that of CANGAROO. The integral gamma-ray flux from HESS J0835-455 has been estimated for the same region as defined by H.E.S.S. from the 1993-1995 data of CANGAROO to be F(> 4.0 +/- 1.6 TeV) = (3.28 +/- 0.92) x 10^{-12} photons cm^{-2} s^{-1}, which is statistically consistent with the integral flux obtained by H.E.S.S.Comment: Published in ApJ, minor improvement
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