247 research outputs found

    Optimisation conjointe d'un codeur source et d'une modulation codée pour la transmission numérique d'images sur canal bruité

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    Dans cet article, nous proposons un système de transmission d'images fixes qui minimise la distorsion introduite par les erreurs résiduelles de transmission. Ce système comprend un codeur source combinant la transformée en cosinus discret et la technique de Quantification Vectorielle (QV). Le taux de compression est égal à 16.7 avec un PSNR de 29.2dB pour l'image Lenna. Les informations issues du codeur source sont ensuite codées par un code en bloc BCH(63,57,3) et transmis par une modulation MAQ-64 (Modulation d'Amplitude en Quadrature). Les paramètres du dictionnaire utilisé pour la QV ainsi que ceux du codeur canal ont été optimisés pour la MAQ-64. Pour le décodage canal, nous avons utilisé un décodage suivant le maximum de vraisemblance (décodage pondéré). Le PSNR de l'image Lenna reconstruite après transmission est égale à 28.6dB pour un SNR canal de 11dB. Ceci représente une faible dégradation du PSNR (0.6dB) en présence d'un Taux d'Erreur Symbole (TES) canal de 10% à l'entrée du décodeur de canal

    Determining the status of chlorinated pesticide residue in some leafy vegetables

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    A study was carried out to identify the bioaccumulation and the ascertain level of chlorinated pesticide residues in three leafy vegetables viz. red amaranth, spinach and Indian spinach collected from city market. The samples were randomly collected from different shops and analyzed by capillary column of Gas Chromatograph Mass Spectrometry (GCMS) with Electron Impact Ionization (EI) method for the detection of chlorinated pesticide. The results of the study revealed that collected samples of red amaranth and spinach were contaminated with some chlorinated substances. But Indian spinach was free of contamination with organochlorine pesticide

    Décodage de codes correcteurs d'erreurs avec information a priori de la source

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    Dans cet article, nous proposons un système complet de transmission d'images fixes. Ce système comprend un quantificateur vectorielle (QV) avec un taux de compression de 9. Les information en sortie du QV sont codées par un code en blocs BCH avant d'être associées aux points de la constellation d'une MAQ-16. Les paramètres du dictionnaire et du code correcteur d'erreur sont optimisés pour la MAQ-16. Nous utilisons un nouvel algorithme de décodage conjoint source-canal pour les codes en blocs. Comparé aux algorithmes de décodage classiques, l'algorithme proposé permet une amélioration, en terme de gain de codage, de 1dB sur le canal de Gauss et de 3 dB sur le canal de Rayleigh pour un taux d'erreur binaire de 10-5. Le PSNR de l'image décodée présente une amélioration de 3 dB comparé aux systèmes classique sans décodage conjoint

    Folk Medicine in the Philippines: A Phenomenological Study of Health-Seeking Individuals

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    Background: Folk medicine refers to traditional healing practices anchored on cultural beliefs of body physiology and health preservation. Reflective of indigenous heritage, it fosters a better understanding of health and disease, healthcare systems, and biocultural adaptation. In the Philippines, Quiapo is a well-known site for folk medicine services, cultural diversity, religious practices, and economic activities. Methods: This study utilized a phenomenological approach to comprehend the lived experiences of health-seeking individuals and the meaning behind their acquisition of folk medicine products. Using convenience sampling, seven participants acquiring folk medicine products in Quiapo on the day of data collection were approached and interviewed on separate instances. The collected data subsequently underwent thematic analysis. Results: Analysis revealed three emergent themes: health-seeking behavior, sources of knowledge, and folk medicine utilization. Health-seeking behavior was linked with the participants’ purpose of going to Quiapo, reasons for utilizing folk medicine, experiences in using folk medicine, and beliefs associated with the product bought. Sources of knowledge tackled the participants’ sources of information about Quiapo and its products. Folk medicine utilization relates to the type of product bought, its perceived medicinal use, and its history of usage. Conclusion: Folk medicine is perceived to be effective alleviating health concerns. The acquisition of such products is attributed to satisfaction from prior experience, distrust in the current healthcare system, family tradition, and intention to supplement existing medical treatment. This study provides health professionals a better understanding of patients who patronize folk medicine, subsequently aiding them in providing a holistic approach to treatment

    One-session treatment for specific phobias: barriers, facilitators and acceptability as perceived by children & young people, parents, and clinicians

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    Between 2015 and 2020 the Alleviating Specific Phobias Experienced by Children Trial (ASPECT) was conducted in the UK to examine the non-inferiority of One-Session Treatment in comparison to Cognitive Behavioural Therapy based interventions for children and young people with specific phobias. A nested qualitative evaluation was conducted as part of this trial to examine the acceptability of One-Session Treatment. Qualitative interviews were conducted with children and young people taking part in the trial, their parents/guardians, and clinicians delivering the intervention, about their experiences and the acceptability of One Session Treatment. Interviews were digitally recorded and transcribed verbatim. Analysis followed a qualitative framework approach, a widely used method of analysing primary qualitative data pertaining to healthcare practices with policy relevance. Stakeholder groups found One Session Treatment to be an acceptable intervention and barriers and facilitators for its implementation into services were also identified. Potential barriers included challenges to patient flow and treatment scepticism, whilst facilitators included adopting a child-centred approach, child readiness and suitability, opportunity for increased momentum, parental support and involvement, and proximal and distal gains. For One Session Treatment’s successful implementation into services, consideration of these barriers is needed and suitability guidance for its use in this population should be developed. Further research exploring children and young people’s experiences of receiving Cognitive Behavioural Therapy and its acceptability in comparison to One Session Treatment would be welcomed

    Biochar versus hydrochar as growth media constituents for ornamental plant cultivation

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    [EN] Biochar and hydrochar have been proposed as novel materials for providing soilless growth media. However, much more knowledge is required before reliable advice can be given on the use of these materials for this purpose. Depending on the material and the technology applied (pyrolysis or hydrothermal carbonization), phytotoxicity and greenhouse gas emissions have been found for certain chars. In this study, our aim was to assess the feasibility of three chars as substrate constituents. We compared two biochars, one from forest waste and the other from olive mill waste, and a hydrochar from forest waste. We studied how chars affected substrate characteristics, plant performance, water economy and respiratory CO2 emission. Substrates containing biochar from forest waste showed the best characteristics, with good air/water relationships and adequate electrical conductivity. Those with biochar from olive mill waste were highly saline and, consequently, low quality. The substrates with hydrochar retained too much water and were poorly aerated, presenting high CO2 concentrations due to high respiratory activity. Plants performed well only when grown in substrates containing a maximum of 25 % biochar from forest waste or hydrochar. After analyzing the char characteristics, we concluded that biochar from forest waste could be safely used as a substrate constituent and is environmentally friendly when applied due to its low salinity and low CO2 emission. However, biochar from olive mill waste and hydrochar need to be improved before they can be used as substrate constituents.This study was funded by the Polytechnic University of Valencia (Projects on New Multidisciplinary Research; PAID-05-12). We thank Molly Marcus-McBride for supervising the English.Fornes Sebastiá, F.; Belda Navarro, RM. (2018). Biochar versus hydrochar as growth media constituents for ornamental plant cultivation. Scientia Agricola (Online). 75(4):304-312. https://doi.org/10.1590/1678-992X-2017-0062S304312754Abad, M., Noguera, P., & Burés, S. (2001). National inventory of organic wastes for use as growing media for ornamental potted plant production: case study in Spain. Bioresource Technology, 77(2), 197-200. doi:10.1016/s0960-8524(00)00152-8Bargmann, I., Martens, R., Rillig, M. C., Kruse, A., & Kücke, M. (2013). Hydrochar amendment promotes microbial immobilization of mineral nitrogen. Journal of Plant Nutrition and Soil Science, 177(1), 59-67. doi:10.1002/jpln.201300154Bargmann, I., Rillig, M. C., Buss, W., Kruse, A., & Kuecke, M. (2013). Hydrochar and Biochar Effects on Germination of Spring Barley. Journal of Agronomy and Crop Science, 199(5), 360-373. doi:10.1111/jac.12024Bedussi, F., Zaccheo, P., & Crippa, L. (2015). Pattern of pore water nutrients in planted and non-planted soilless substrates as affected by the addition of biochars from wood gasification. Biology and Fertility of Soils, 51(5), 625-635. doi:10.1007/s00374-015-1011-6Belda, R. M., Lidón, A., & Fornes, F. (2016). Biochars and hydrochars as substrate constituents for soilless growth of myrtle and mastic. Industrial Crops and Products, 94, 132-142. doi:10.1016/j.indcrop.2016.08.024Costello, R. C., & Sullivan, D. M. (2013). Determining the pH Buffering Capacity of Compost Via Titration with Dilute Sulfuric Acid. Waste and Biomass Valorization, 5(3), 505-513. doi:10.1007/s12649-013-9279-yFernandes, C., & Corá, J. E. (2004). Bulk density and relationship air/water of horticultural substrate. Scientia Agricola, 61(4), 446-450. doi:10.1590/s0103-90162004000400015Fornes, F., Belda, R. M., Carrión, C., Noguera, V., García-Agustín, P., & Abad, M. (2007). Pre-conditioning ornamental plants to drought by means of saline water irrigation as related to salinity tolerance. Scientia Horticulturae, 113(1), 52-59. doi:10.1016/j.scienta.2007.01.008Fornes, F., Belda, R. M., & Lidón, A. (2015). Analysis of two biochars and one hydrochar from different feedstock: focus set on environmental, nutritional and horticultural considerations. Journal of Cleaner Production, 86, 40-48. doi:10.1016/j.jclepro.2014.08.057Fornes, F., & Belda, R. M. (2017). Acidification with nitric acid improves chemical characteristics and reduces phytotoxicity of alkaline chars. Journal of Environmental Management, 191, 237-243. doi:10.1016/j.jenvman.2017.01.026Fornes, F., Belda, R. M., Fernández de Córdova, P., & Cebolla-Cornejo, J. (2017). Assessment of biochar and hydrochar as minor to major constituents of growing media for containerized tomato production. Journal of the Science of Food and Agriculture, 97(11), 3675-3684. doi:10.1002/jsfa.8227Fornes, F., Carrión, C., García-de-la-Fuente, R., Puchades, R., & Abad, M. (2010). Leaching composted lignocellulosic wastes to prepare container media: Feasibility and environmental concerns. Journal of Environmental Management, 91(8), 1747-1755. doi:10.1016/j.jenvman.2010.03.017GARCIADELAFUENTE, R., CARRION, C., BOTELLA, S., FORNES, F., NOGUERA, V., & ABAD, M. (2007). Biological oxidation of elemental sulphur added to three composts from different feedstocks to reduce their pH for horticultural purposes. Bioresource Technology, 98(18), 3561-3569. doi:10.1016/j.biortech.2006.11.008Genty, B., Briantais, J.-M., & Baker, N. R. (1989). The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochimica et Biophysica Acta (BBA) - General Subjects, 990(1), 87-92. doi:10.1016/s0304-4165(89)80016-9Hoitink, H. A. J., Stone, A. G., & Han, D. Y. (1997). Suppression of Plant Diseases by Composts. HortScience, 32(2), 184-187. doi:10.21273/hortsci.32.2.184Libra, J. A., Ro, K. S., Kammann, C., Funke, A., Berge, N. D., Neubauer, Y., … Emmerich, K.-H. (2011). Hydrothermal carbonization of biomass residuals: a comparative review of the chemistry, processes and applications of wet and dry pyrolysis. Biofuels, 2(1), 71-106. doi:10.4155/bfs.10.81Mazuela, P., Salas, M. del C., & Urrestarazu, M. (2005). Vegetable Waste Compost as Substrate for Melon. Communications in Soil Science and Plant Analysis, 36(11-12), 1557-1572. doi:10.1081/css-200059054Méndez, A., Paz-Ferreiro, J., Gil, E., & Gascó, G. (2015). The effect of paper sludge and biochar addition on brown peat and coir based growing media properties. Scientia Horticulturae, 193, 225-230. doi:10.1016/j.scienta.2015.07.032Nieto, A., Gascó, G., Paz-Ferreiro, J., Fernández, J. M., Plaza, C., & Méndez, A. (2016). The effect of pruning waste and biochar addition on brown peat based growing media properties. Scientia Horticulturae, 199, 142-148. doi:10.1016/j.scienta.2015.12.012Sáez, J. A., Belda, R. M., Bernal, M. P., & Fornes, F. (2016). Biochar improves agro-environmental aspects of pig slurry compost as a substrate for crops with energy and remediation uses. Industrial Crops and Products, 94, 97-106. doi:10.1016/j.indcrop.2016.08.035Smith, B. R., Fisher, P. R., & Argo, W. R. (2004). Growth and Pigment Content of Container-grown Impatiens and Petunia in Relation to Root Substrate pH and Applied Micronutrient Concentration. HortScience, 39(6), 1421-1425. doi:10.21273/hortsci.39.6.1421Solaiman, Z. M., Murphy, D. V., & Abbott, L. K. (2011). Biochars influence seed germination and early growth of seedlings. Plant and Soil, 353(1-2), 273-287. doi:10.1007/s11104-011-1031-4Steiner, C., & Harttung, T. (2014). Biochar as a growing media additive and peat substitute. Solid Earth, 5(2), 995-999. doi:10.5194/se-5-995-2014Tian, Y., Sun, X., Li, S., Wang, H., Wang, L., Cao, J., & Zhang, L. (2012). Biochar made from green waste as peat substitute in growth media for Calathea rotundifola cv. Fasciata. Scientia Horticulturae, 143, 15-18. doi:10.1016/j.scienta.2012.05.018Vaughn, S. F., Eller, F. J., Evangelista, R. L., Moser, B. R., Lee, E., Wagner, R. E., & Peterson, S. C. (2015). Evaluation of biochar-anaerobic potato digestate mixtures as renewable components of horticultural potting media. Industrial Crops and Products, 65, 467-471. doi:10.1016/j.indcrop.2014.10.04

    Stepped-wedge cluster-randomised controlled trial to assess the cardiovascular health effects of a managed aquifer recharge initiative to reduce drinking water salinity in southwest coastal Bangladesh: study design and rationale.

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    INTRODUCTION: Saltwater intrusion and salinisation have contributed to drinking water scarcity in many coastal regions globally, leading to dependence on alternative sources for water supply. In southwest coastal Bangladesh, communities have few options but to drink brackish groundwater which has been associated with high blood pressure among the adult population, and pre-eclampsia and gestational hypertension among pregnant women. Managed aquifer recharge (MAR), the purposeful recharge of surface water or rainwater to aquifers to bring hydrological equilibrium, is a potential solution for salinity problem in southwest coastal Bangladesh by creating a freshwater lens within the brackish aquifer. Our study aims to evaluate whether consumption of MAR water improves human health, particularly by reducing blood pressure among communities in coastal Bangladesh. METHODS AND ANALYSIS: The study employs a stepped-wedge cluster-randomised controlled community trial design in 16 communities over five monthly visits. During each visit, we will collect data on participants' source of drinking and cooking water and measure the salinity level and electrical conductivity of household stored water. At each visit, we will also measure the blood pressure of participants ≥20 years of age and pregnant women and collect urine samples for urinary sodium and protein measurements. We will use generalised linear mixed models to determine the association of access to MAR water on blood pressure of the participants. ETHICS AND DISSEMINATION: The study protocol has been reviewed and approved by the Institutional Review Boards of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). Informed written consent will be taken from all the participants. This study is funded by Wellcome Trust, UK. The study findings will be disseminated to the government partners, at research conferences and in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT02746003; Pre-results

    The Effects of Ash and Black Carbon (Biochar) on Germination of Different Tree Species

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    Forest fires generate large amounts of ash and biochar, or black carbon (BC), that cover the soil surface, interacting with the soil’s constituents and its seedbank. This study concerns reproductive ecology assessments supported by molecular characterisation to improve our understanding of the effects of fire and fire residues on the germination behaviour of 12 arboreal species with a wide geographic distribution. For this purpose, we analysed the effects of three ash and one BC concentration on the germination of Acacia dealbata Link, A. longifolia (Andrews) Willd., A. mearnsii De Wild., A. melanoxylon R. Br., Pinus nigra Arnold, P. pinaster Aiton, P. radiata D. Don, P. sylvestris L., Quercus ilex L., Q. pyrenaica Willd., Q. robur L., and Q. rubra L. Each tree species was exposed to ash and BC created from its foliage or twigs (except for Q. rubra, which was exposed to ash and BC of Ulex europaeus L.). We monitored germination percentage, the T50 parameter, and tracked the development of germination over time (up to 1 yr). The BC of A. dealbata, P. pinaster, and Q. robur was analysed by pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS) to assess the molecular composition. In six species, ash inhibited the germination, while in another five species, germination was not affected by ash or by BC. In Q. rubra, ash and BC stimulated its germination. This stimulating effect of the BC on Q. rubra is likely to be related to the chemical composition of the ash and BC obtained from Ulex feedstock. The BC of U. europaeus has a very different molecular composition than the other BC samples analysed, which, together with other factors, probably allowed for its germination stimulating effects.This study was carried out within the Project 10MDS200007PR, financed by the Xunta de Galicia; the Project AGL2013-48189-C2-2-R, financed by the Ministerio de Economía y Competitividad, Spain; and FEDERS
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