Small-sized reverberation chamber for the measurement of sound absorption

[ES] Cámara reverberante de tamaño reducido para medidas de la absorción sonora. En este trabajo se muestra el diseño, construcción, calibración y automatización de una cámara reverberante para pequeñas muestras. Se ha buscado un equilibro entre la reducción de tamaño de las muestras para disminuir los costes de fabricación de materiales, y el volumen adecuado que permita obtener valores fiables a determinadas frecuencias. La cámara reverberante construida tiene 1.12 m3 de volumen y permite la medida de muestras de 0.3 m2. La colocación de difusores para aumentar el grado de difusión, y la automatización de las medidas, disminuyen los errores de ensayo. Se muestran también diferentes campañas comparativas de medidas en la cámara reverberante para pequeñas muestras y en la cámara normalizada. Puede verse un buen grado de ajuste entre ambas dentro del rango de frecuencias válido. Por tanto, se muestra un pequeño laboratorio que permite comparar muestras y tomar decisiones, antes de realizar la fabricación de grandes tamaños.[EN] This paper presents the design, construction, calibration and automation of a reverberation chamber for small samples. A balance has been sought between reducing sample size, to reduce the manufacturing costs of materials, and finding the appropriate volume of the chamber, to obtain reliable values at high and mid frequencies. The small-sized reverberation chamber, that was built, has a volume of 1.12 m3 and allows for the testing of samples of 0.3 m2. By using diffusers, to improve the diffusion degree, and automating measurements, we were able to improve the reliability of the results, thus reducing test errors. Several comparison studies of the measurements of the small-sized reverberation chamber and the standardised reverberation chamber are shown, and a good degree of adjustment can be seen between them, within the range of valid frequencies. This paper presents a small laboratory for comparing samples and making decisions before the manufacturing of larger sizes.This project involved the contribution of the European Union’s financial instrument, LIFE: ‘LIFE 09 ENV/ES/461: Demonstrative solutions to reduce noise pollution in industrial, using finishing technologies in textile materials’ and that of the European project ‘WOOL4BUILD ECO/13/630249/SI2.681252, CIP-ECO-INNOVATION: Improved isolation material for eco-building based on natural wool’.Rey Tormos, RMD.; Alba Fernández, J.; Bertó Carbó, L.; Gregori, A. (2017). Small-sized reverberation chamber for the measurement of sound absorption. Materiales de Construcción. 67(328):1-9. doi:10.3989/mc.2017.07316S1967328Del Rey, R., Alba, J., Ramis, J., & Sanchís, V. J. (2011). Nuevos materiales absorbentes acústicos obtenidos a partir de restos de botellas de plástico. Materiales de Construcción, 61(304), 547-558. doi:10.3989/mc.2011.59610Maderuelo-Sanz, R., Nadal-Gisbert, A. V., Crespo-Amorós, J. E., & Parres-García, F. (2012). A novel sound absorber with recycled fibers coming from end of life tires (ELTs). Applied Acoustics, 73(4), 402-408. doi:10.1016/j.apacoust.2011.12.001Rey, R. del, Alba, J., Arenas, J. P., & Sanchis, V. J. (2012). An empirical modelling of porous sound absorbing materials made of recycled foam. Applied Acoustics, 73(6-7), 604-609. doi:10.1016/j.apacoust.2011.12.009Fatima, S., & Mohanty, A. R. (2011). Acoustical and fire-retardant properties of jute composite materials. Applied Acoustics, 72(2-3), 108-114. doi:10.1016/j.apacoust.2010.10.005Ramis, J., Alba, J., Del Rey, R., Escuder, E., & Sanchís, V. J. (2010). Nuevos materiales absorbentes acústicos basados en fibra de kenaf. Materiales de Construcción, 60(299), 133-143. doi:10.3989/mc.2010.50809Ramis, J., Del Rey, R., Alba, J., Godinho, L., & Carbajo, J. (2014). A model for acoustic absorbent materials derived from coconut fiber. Materiales de Construcción, 64(313), e008. doi:10.3989/mc.2014.00513Díaz, C., Jiménez, M., Navacerrada, M. A., & Pedrero, A. (2010). Propiedades acústicas de los paneles de carrizo. Materiales de Construcción, 62(305), 55-66. doi:10.3989/mc.2010.60510Arenas, J. P., Rebolledo, J., Del Rey, R., & Alba, J. (2014). Sound Absorption Properties of Unbleached Cellulose Loose-Fill Insulation Material. BioResources, 9(4). doi:10.15376/biores.9.4.6227-624011. Bulent, E.; Aykut, K.; Haluk, K. (2012). Improving Sound Absorption Property of Polyurethane Foams by Adding Tea-Leaf Fibers. Arch. Acoust. 37 [4] 515-520.16. Hernández, D.; Liu, E.J.; Huang, J.H.; Liu, Y.C. (2015). Design and Construction of a Small Reverberation Chamber Applied to Absorption and Scattering Acoustic Measurements. Advanced Materials Research. 1077. 197–202.Bradley, D. T., Müller-Trapet, M., Adelgren, J., & Vorländer, M. (2014). Effect of boundary diffusers in a reverberation chamber: Standardized diffuse field quantifiers. The Journal of the Acoustical Society of America, 135(4), 1898-1906. doi:10.1121/1.486629123. Skålevik, M. (2011). Schroeder Frequency revisited. International Congress Forum Acustikum – Aalborg, Denmark – 2011

Revalorisation of chito-oligosaccharides obtained from fishery by-products as natural antimicrobials

La quitina es el polímero más común en la Tierra después de la celulosa y se encuentra principalmente en los caparazones de los crustáceos, entre otros. A partir de la quitina se puede obtener como derivado desacetilado el quitosano, con propiedades específicas como su capacidad biocida, que le ha proporcionado múltiples aplicaciones potenciales. No obstante, debido a su baja so-lubilidad, estas aplicaciones están limitadas y cobran especial importancia los quito-oligosacáridos (COS), productos obtenidos a partir del quitosano. Por ello y ante el aumento significativo de los subproductos de la industria pesquera en los últimos años, el objetivo del presente trabajo fue evaluar la capacidad biocida de diferentes formulaciones desarrolladas a partir de COS extraídos de subproductos de la industria pesquera frente a los principales microorganismos alimentarios, para su revalorización como antimicrobianos naturales. Con dicho fin, se evaluó la capacidad biocida de siete formulaciones siguiendo la norma UNE-EN 1276, frente a distintas especies de hongos y bacterias, mediante el recuento en placa. Los resultados obtenidos mostraron que todos los formulados presentaron capacidad biocida frente a los microorganismos estudiados y, en base a ellos, se pudo concluir que el formulado basado en COS3 es el candidato que mayor proyección presenta para el desarrollo de un futuro producto biocida sostenible.Chitin is the most common polymer on Earth after cellulose and it is found mainly in the shells of crustaceans, among others. Chitosan can be obtained from chitin, it is a deacetylated deriva-tive with specific properties such as biocide capacity, which has provided it with many potential applications. However, due to its low solubility these applications are limited and chito-oligosaccharides (COS), products obtained from chitosan, take on special interest. For this reason and before the significant increase in by-products of the fishing industry in recent years, the objective of this project was to evaluate the biocide capacity of different formulations developed from COS extracted from by-products of the fishing industry against the main food microorga-nisms, for their revaluation as natural antimicrobials. For that purpose, the biocide capacity of seven formulations was evaluated by plate count following the UNE-EN 1276 standard, against different species of fungi and bacteria. The results obtained showed that all the formulations pre-sented biocide capacity against the studied microorganisms and, based on them, it was possible to conclude that the formula based on COS3 is the candidate with the greatest projection for the development of a future sustainable biocide product.Ciencias Experimentale

Chronic obstructive pulmonary disease (COPD) as a disease of early aging: evidence from the epiChron cohort

Background: Aging is an important risk factor for most chronic diseases. Patients with COPD develop more comorbidities than non-COPD subjects. We hypothesized that the development of comorbidities characteristically affecting the elderly occur at an earlier age in subjects with the diagnosis of COPD. Methods and findings: We included all subjects carrying the diagnosis of COPD (n = 27,617), and a similar number of age and sex matched individuals without the diagnosis, extracted from the 727,241 records of individuals 40 years and older included in the EpiChron Cohort (Aragon, Spain). We compared the cumulative number of comorbidities, their prevalence and the mortality risk between both groups. Using network analysis, we explored the connectivity between comorbidities and the most influential comorbidities in both groups. We divided the groups into 5 incremental age categories and compared their comorbidity networks. We then selected those comorbidities known to affect primarily the elderly and compared their prevalence across the 5 age groups. In addition, we replicated the analysis in the smokers' subgroup to correct for the confounding effect of cigarette smoking. Subjects with COPD had more comorbidities and died at a younger age compared to controls. Comparison of both cohorts across 5 incremental age groups showed that the number of comorbidities, the prevalence of diseases characteristic of aging and network's density for the COPD group aged 56-65 were similar to those of non-COPD 15 to 20 years older. The findings persisted after adjusting for smoking. Conclusion: Multimorbidity increases with age but in patients carrying the diagnosis of COPD, these comorbidities are seen at an earlier age

List of amphibian species across the globe whose ranges and macrohabitat overlap with those of L. humile populations

Invasive species cause major ecosystem impacts. To prioritise management, it is first necessary to recognise which invaders have the highest impact, as outlined by the Convention on Biological Diversity’s Strategic Plan 2020. We show for the first time that chemical compounds previously shown to be used in ant defence against other ant species can also be used to prey upon vertebrates of relatively greater size. We estimate the number of amphibian species whose ranges overlap with those of the Argentine ant across the globe and examine the likely global threat to terrestrial amphibians, an already endangered taxonomic group.Peer reviewe

Pulmonary arterial enlargement predicts long-term survival in COPD patients

Rationale Pulmonary artery enlargement (PAE) is associated with exacerbations in Chronic Obstructive Pulmonary Disease (COPD) and with survival in moderate to severe patients. The potential role of PAE in survival prediction has not been compared with other clinical and physiological prognostic markers. Methods In 188 patients with COPD, PA diameter was measured on a chest CT and the following clinical and physiological parameters registered: age, gender, smoking status, pack-years history, dyspnea, lung function, exercise capacity, Body Mass Index, BODE index and history of exacerbations in year prior to enrolment. Proportional Cox regression analysis determined the best predictor of all cause survival. Results During 83 months (±42), 43 patients died. Age, pack-years history, smoking status, BMI, FEV1%, six minute walking distance, Modified Medical Research Council dyspnea scale, BODE index, exacerbation rate prior to enrollment, PA diameter and PAE (diameter≥30mm) were associated with survival. In the multivariable analysis, age (HR: 1.08; 95%CI: 1.03–1.12, p<0.001) and PAE (HR: 2.78; 95%CI: 1.35–5.75, p = 0.006) were the most powerful parameters associated with all-cause mortality. Conclusions In this prospective observational study of COPD patients with mild to moderate airflow limitation, PAE was the best predictor of long-term survival along with age

Chronic Obstructive Pulmonary Disease (COPD) as a disease of early aging: Evidence from the EpiChron Cohort

Background: Aging is an important risk factor for most chronic diseases. Patients with COPD develop more comorbidities than non-COPD subjects. We hypothesized that the development of comorbidities characteristically affecting the elderly occur at an earlier age in subjects with the diagnosis of COPD. Methods and findings We included all subjects carrying the diagnosis of COPD (n = 27,617), and a similar number of age and sex matched individuals without the diagnosis, extracted from the 727,241 records of individuals 40 years and older included in the EpiChron Cohort (Aragon, Spain). We compared the cumulative number of comorbidities, their prevalence and the mortality risk between both groups. Using network analysis, we explored the connectivity between comorbidities and the most influential comorbidities in both groups. We divided the groups into 5 incremental age categories and compared their comorbidity networks. We then selected those comorbidities known to affect primarily the elderly and compared their prevalence across the 5 age groups. In addition, we replicated the analysis in the smokers’ subgroup to correct for the confounding effect of cigarette smoking. Subjects with COPD had more comorbidities and died at a younger age compared to controls. Comparison of both cohorts across 5 incremental age groups showed that the number of comorbidities, the prevalence of diseases characteristic of aging and network’s density for the COPD group aged 56–65 were similar to those of non-COPD 15 to 20 years older. The findings persisted after adjusting for smoking. Conclusion: Multimorbidity increases with age but in patients carrying the diagnosis of COPD, these comorbidities are seen at an earlier age

Chronic obstructive pulmonary disease (COPD) as a disease of early aging: evidence from the epiChron cohort

Background: Aging is an important risk factor for most chronic diseases. Patients with COPD develop more comorbidities than non-COPD subjects. We hypothesized that the development of comorbidities characteristically affecting the elderly occur at an earlier age in subjects with the diagnosis of COPD. Methods and findings: We included all subjects carrying the diagnosis of COPD (n = 27,617), and a similar number of age and sex matched individuals without the diagnosis, extracted from the 727,241 records of individuals 40 years and older included in the EpiChron Cohort (Aragon, Spain). We compared the cumulative number of comorbidities, their prevalence and the mortality risk between both groups. Using network analysis, we explored the connectivity between comorbidities and the most influential comorbidities in both groups. We divided the groups into 5 incremental age categories and compared their comorbidity networks. We then selected those comorbidities known to affect primarily the elderly and compared their prevalence across the 5 age groups. In addition, we replicated the analysis in the smokers' subgroup to correct for the confounding effect of cigarette smoking. Subjects with COPD had more comorbidities and died at a younger age compared to controls. Comparison of both cohorts across 5 incremental age groups showed that the number of comorbidities, the prevalence of diseases characteristic of aging and network's density for the COPD group aged 56-65 were similar to those of non-COPD 15 to 20 years older. The findings persisted after adjusting for smoking. Conclusion: Multimorbidity increases with age but in patients carrying the diagnosis of COPD, these comorbidities are seen at an earlier age

Prevalence comparison of those diseases mostly occurring in elders.

<p>Prevalence comparison of those diseases mostly occurring in elders.</p

Number of comorbidities per individual by age brackets and total mortality.

<p>Each band represent the number of comorbidities/patient, and the width the proportion of individuals with that number of comorbidities at different age brackets (x-axis). Panel A represent those patients carrying the diagnosis of COPD and Panel B those without COPD. The stacked “Grim Reaper” represents the number of death at 3 years of follow-up (5,247 for COPD and 2,911 in the non-COPD) and their position is located at the mean age of death; one full “Grim Reaper” represents 1,000 deaths.</p

Prevalence of co-morbidities commonly seen in the elderly between COPD and non-COPD patients at five different age categories.

<p>Solid dots ● represent COPD patients and hollow dots ○ represent non-COPD patients. The size of the dots is proportional to the number of links (degrees) in their respective networks. Note, the prevalence (vertical axis) is higher in the COPD group and reach those values seen in non-COPD at an earlier age (horizontal axis). Comorbidities where the prevalence in COPD is similar to controls 10–20 years earlier are highlighted with a solid arrow ↓ and hollow arrow ⇓ in non-COPD. We show in this <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193143#pone.0193143.g002" target="_blank">Fig 2</a> representative examples of comorbidities of the elder (osteoporosis and atherosclerosis). For the complete list of comorbidities seen in the elders please refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193143#pone.0193143.s009" target="_blank">S9 Fig</a>.</p