Growing monitoring in sea cages: TS measurements issues

Hydroacoustic monitoring of fish growing in sea cages needs of an accurate relationship between fish size and target strength (TS) for every species of commercial interest. We discuss the conditions for TS measurement in near range conditions in sea cages for the case of the dorsal and ventral aspects of gilthead sea bream and bluefin tuna. Gilthead sea bream dorsal and ventral TS distributions, obtained with a split beam echosounder, are unimodal and the same results are derived for single beam data analysis when specific processing threshold criteria are applied. The expected linear relationship between the average TS and the logarithm of fish length is only found for the ventral case, being more accurate the uncompensated TS single beam analysis, probably due to near range errors. Bluefin tuna dorsal measurements performed in a fattening farm from February to July did not show a significant variation of TS distributions, and we propose a synchronized system of echosounder and video recordings, in order to relate target strength and orientation and size of specific tuna in the acoustic beam. Preliminary results indicate that only ventral TS values correlate properly with tuna size

Formation of collimated sound beams by three-dimensional sonic crystals

A theoretical and experimental study of the propagation of sound beams in- and behind three-dimensional sonic crystals at frequencies close to the band edges is presented. An efficient collimation of the beam behind the crystal is predicted and experimentally demonstrated. This effect could allow the design of sources of high spatial quality sound beams

Wave focusing using symmetry matching in axisymmetric acoustic gradient index lenses

Copyright 2013 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Romero García, V.; Cebrecos Ruiz, A.; Picó Vila, R.; Sánchez Morcillo, VJ.; García-Raffi, LM.; Sánchez Pérez, JV. (2013). Wave focusing using symmetry matching in axisymmetric acoustic gradient index lenses. Applied Physics Letters. 103(26):264106-264106. doi:10.1063/1.4860535 and may be found at http://scitation.aip.org/The symmetry matching between the source and the lens results in fundamental interest for lensing applications. In this work, we have modeled an axisymmetric gradient index (GRIN) lens made of rigid toroidal scatterers embedded in air considering this symmetry matching with radially symmetric sources. The sound amplification obtained in the focal spot of the reported lens (8.24 dB experimentally) shows the efficiency of the axisymmetric lenses with respect to the previous Cartesian acoustic GRIN lenses. The axisymmetric design opens new possibilities in lensing applications in different branches of science and technology.The work was supported by Spanish Ministry of Science and Innovation and European Union FEDER through Project Nos. FIS2011-29734-C02-01 and -02 and PAID 2012/253. V. R. G. is grateful for the support of post-doctoral contracts of the UPV CEI-01-11.Romero García, V.; Cebrecos Ruiz, A.; Picó Vila, R.; Sánchez Morcillo, VJ.; García-Raffi, LM.; Sánchez Pérez, JV. (2013). Wave focusing using symmetry matching in axisymmetric acoustic gradient index lenses. Applied Physics Letters. 103(26):264106-264106. https://doi.org/10.1063/1.4860535S26410626410610326John, S. (1987). Strong localization of photons in certain disordered dielectric superlattices. Physical Review Letters, 58(23), 2486-2489. doi:10.1103/physrevlett.58.2486Yablonovitch, E. (1987). Inhibited Spontaneous Emission in Solid-State Physics and Electronics. Physical Review Letters, 58(20), 2059-2062. doi:10.1103/physrevlett.58.2059Kushwaha, M. S., Halevi, P., Dobrzynski, L., & Djafari-Rouhani, B. (1993). Acoustic band structure of periodic elastic composites. Physical Review Letters, 71(13), 2022-2025. doi:10.1103/physrevlett.71.2022Martínez-Sala, R., Sancho, J., Sánchez, J. V., Gómez, V., Llinares, J., & Meseguer, F. (1995). Sound attenuation by sculpture. Nature, 378(6554), 241-241. doi:10.1038/378241a0Pennec, Y., Vasseur, J. O., Djafari-Rouhani, B., Dobrzyński, L., & Deymier, P. A. (2010). Two-dimensional phononic crystals: Examples and applications. Surface Science Reports, 65(8), 229-291. doi:10.1016/j.surfrep.2010.08.002Cervera, F., Sanchis, L., Sánchez-Pérez, J. V., Martínez-Sala, R., Rubio, C., Meseguer, F., … Sánchez-Dehesa, J. (2001). Refractive Acoustic Devices for Airborne Sound. Physical Review Letters, 88(2). doi:10.1103/physrevlett.88.023902Krokhin, A. A., Arriaga, J., & Gumen, L. N. (2003). Speed of Sound in Periodic Elastic Composites. Physical Review Letters, 91(26). doi:10.1103/physrevlett.91.264302Sánchez-Pérez, J. V., Caballero, D., Mártinez-Sala, R., Rubio, C., Sánchez-Dehesa, J., Meseguer, F., … Gálvez, F. (1998). Sound Attenuation by a Two-Dimensional Array of Rigid Cylinders. Physical Review Letters, 80(24), 5325-5328. doi:10.1103/physrevlett.80.5325Sheng, P. (1995). Wave Scattering and the Effective Medium. Introduction to Wave Scattering, Localization, and Mesoscopic Phenomena, 49-113. doi:10.1016/b978-012639845-8/50003-4Mei, J., Liu, Z., Wen, W., & Sheng, P. (2006). Effective Mass Density of Fluid-Solid Composites. Physical Review Letters, 96(2). doi:10.1103/physrevlett.96.024301Lin, S.-C. S., Huang, T. J., Sun, J.-H., & Wu, T.-T. (2009). Gradient-index phononic crystals. Physical Review B, 79(9). doi:10.1103/physrevb.79.094302Zigoneanu, L., Popa, B.-I., & Cummer, S. A. (2011). Design and measurements of a broadband two-dimensional acoustic lens. Physical Review B, 84(2). doi:10.1103/physrevb.84.024305Li, Y., Liang, B., Tao, X., Zhu, X., Zou, X., & Cheng, J. (2012). Acoustic focusing by coiling up space. Applied Physics Letters, 101(23), 233508. doi:10.1063/1.4769984Yang, S., Page, J. H., Liu, Z., Cowan, M. L., Chan, C. T., & Sheng, P. (2004). Focusing of Sound in a 3D Phononic Crystal. Physical Review Letters, 93(2). doi:10.1103/physrevlett.93.024301Luo, C., Johnson, S. G., Joannopoulos, J. D., & Pendry, J. B. (2002). All-angle negative refraction without negative effective index. Physical Review B, 65(20). doi:10.1103/physrevb.65.201104Ke, M., Liu, Z., Qiu, C., Wang, W., Shi, J., Wen, W., & Sheng, P. (2005). Negative-refraction imaging with two-dimensional phononic crystals. Physical Review B, 72(6). doi:10.1103/physrevb.72.064306SAMIMY, M., KIM, J.-H., KEARNEY-FISCHER, M., & SINHA, A. (2010). Acoustic and flow fields of an excited high Reynolds number axisymmetric supersonic jet. Journal of Fluid Mechanics, 656, 507-529. doi:10.1017/s0022112010001357Choe, Y., Kim, J. W., Shung, K. K., & Kim, E. S. (2011). Microparticle trapping in an ultrasonic Bessel beam. Applied Physics Letters, 99(23), 233704. doi:10.1063/1.3665615Baac, H. W., Ok, J. G., Maxwell, A., Lee, K.-T., Chen, Y.-C., Hart, A. J., … Guo, L. J. (2012). Carbon-Nanotube Optoacoustic Lens for Focused Ultrasound Generation and High-Precision Targeted Therapy. Scientific Reports, 2(1). doi:10.1038/srep00989Chang, T. M., Dupont, G., Enoch, S., & Guenneau, S. (2012). Enhanced control of light and sound trajectories with three-dimensional gradient index lenses. New Journal of Physics, 14(3), 035011. doi:10.1088/1367-2630/14/3/035011Sanchis, L., Yánez, A., Galindo, P. L., Pizarro, J., & Pastor, J. M. (2010). Three-dimensional acoustic lenses with axial symmetry. Applied Physics Letters, 97(5), 054103. doi:10.1063/1.3474616Gomez-Reino, C., Perez, M. V., & Bao, C. (2002). Gradient-Index Optics. doi:10.1007/978-3-662-04741-5Romero-García, V., Sánchez-Pérez, J. V., Castiñeira-Ibáñez, S., & Garcia-Raffi, L. M. (2010). Evidences of evanescent Bloch waves in phononic crystals. Applied Physics Letters, 96(12), 124102. doi:10.1063/1.3367739Climente, A., Torrent, D., & Sánchez-Dehesa, J. (2010). Sound focusing by gradient index sonic lenses. Applied Physics Letters, 97(10), 104103. doi:10.1063/1.3488349Martin, T. P., Nicholas, M., Orris, G. J., Cai, L.-W., Torrent, D., & Sánchez-Dehesa, J. (2010). Sonic gradient index lens for aqueous applications. Applied Physics Letters, 97(11), 113503. doi:10.1063/1.348937

Acoustically penetrable sonic crystals based on fluid-like scatterers

We propose a periodic structure that behaves as a fluid fluid composite for sound waves, where the building blocks are clusters of rigid scatterers. Such building-blocks are penetrable for acoustic waves, and their properties can be tuned by selecting the filling fraction. The equivalence with a fluid fluid system of such a doubly periodic composite is tested analytical and experimentally. Because of the fluid-like character of the scatterers, sound structure interaction is negligible, and the propagation can be described by scalar models, analogous to those used in electromagnetics. As an example, the case of focusing of evanescent waves and the guided propagation of acoustic waves along an array of penetrable elements is discussed in detail. The proposed structure may be a real alternative to design a low contrast and acoustically penetrable medium where new properties as those shown in this work could be experimentally realized.We acknowledge financial support by Spanish Ministerio de Economia y Competitividad and European Union FEDER through project FIS2011-29731-C02-01 and -02. VRG is grateful for the financial support of the post-doctoral grant from the "Pays de la Loire". ACR is grateful for the support of the Programa de Ayudas e Iniciativas de Investigacin (PAID) of the UPV.Cebrecos Ruiz, A.; Romero García, V.; Picó Vila, R.; Sánchez Morcillo, VJ.; Botey, M.; Herrero, R.; Cheng, YC.... (2015). Acoustically penetrable sonic crystals based on fluid-like scatterers. Journal of Physics D-Applied Physics. 48(2):25501-25510. https://doi.org/10.1088/0022-3727/48/2/025501S255012551048

Experimental evidence of rainbow trapping and Bloch oscillations of torsional waves in chirped metallic beams

[EN] The Bloch oscillations (BO) and the rainbow trapping (RT) are two apparently unrelated phenomena, the former arising in solid state physics and the latter in metamaterials. A Bloch oscillation, on the one hand, is a counter-intuitive effect in which electrons start to oscillate in a crystalline structure when a static electric field is applied. This effect has been observed not only in solid state physics but also in optical and acoustical structured systems since a static electric field can be mimicked by a chirped structure. The RT, on the other hand, is a phenomenon in which the speed of a wave packet is slowed down in a dielectric structure; different colors then arrive to different depths within the structure thus separating the colors also in time. Here we show experimentally the emergence of both phenomena studying the propagation of torsional waves in chirped metallic beams. Experiments are performed in three aluminum beams in which different structures were machined: one periodic and two chirped. For the smaller value of the chirping parameter the wave packets, with different central frequencies, are back-scattered at different positions inside the corrugated beam; the packets with higher central frequencies being the ones with larger penetration depths. This behavior represents the mechanical analogue of the rainbow trapping effect. This phenomenon is the precursor of the mechanical Bloch oscillations, which are here demonstrated for a larger value of the chirping parameter. It is observed that the oscillatory behavior observed at small values of the chirp parameter is rectified according to the penetration length of the wave packet.Work partially supported by DGAPA-UNAM under projects PAPIIT IN103115 and IN109318 and by CONACYT project 284096. A.A.L. acknowledges CONACYT for the support granted to pursue his Ph.D. studies. G. Baez received CONACYT's financial support. RAMS received support from DGAPA-UNAM under program PASPA. We thank M. Martinez, A. Martinez, V. Dominguez-Rocha, E. Flores and E. Sadurni for invaluable comments. F.C., A.C. and J.S-D. acknowledge the support by the Ministerio de Economa y Competitividad of the Spanish government, and the European Union FEDER through project TEC2014-53088-C3-1-R.Arreola-Lucas, A.; Baez, G.; Cervera Moreno, FS.; Climente Alarcón, A.; Mendez-Sanchez, R.; Sánchez-Dehesa Moreno-Cid, J. (2019). Experimental evidence of rainbow trapping and Bloch oscillations of torsional waves in chirped metallic beams. Scientific Reports. 9:1860-1872. https://doi.org/10.1038/s41598-018-37842-7S186018729Ascroft, N. W. & Mermin, N. D. Solid State Physics (Hold, Reinhart & Winston, 1972).Kadic, M., Buckmann, T., Schittny, R. & Wegener, M. Metamaterials beyond electromagnetism. Rep. Prog. Phys. 76, 126501 (2013).Cummer, S. A., Christensen, J. & Alù, A. Controlling sound with acoustic metamaterials. Nat. Rev. Mat. 1, 16001 (2016).Tsakmakidis, K. L., Boarman, A. D. & Hess, O. Trapped rainbow storage of light in metamaterials. Nature 450, 397–401 (2007).Kathryn, H. et al. Designing perturbative metamaterials from discrete models. Nat. Mat. 17, 323–328 (2018).de Lima, M. M. Jr., Kosevich, Y. A., Santos, P. V. & Cantarero, A. Surface acoustic Bloch oscillations and Wannier-Stark ladders and Landau-Zenner tunneling in a solid. Phys. Rev. Lett. 104, 165502, https://doi.org/10.1103/PhysRevLett.104.165502 (2010).Tian, Z. & Yu, L. Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates. Sci. Rep. 7, 40004, https://doi.org/10.1038/srep40004 (2017).Waschke, C. et al. Coherent submillimeter-wave emission from bloch oscillations in a semiconductor superlattice. Phys. Rev. Lett. 70, 3319–3322, https://doi.org/10.1103/PhysRevLett.70.3319 (1993).Sapienza, R. et al. Optical analogue of electronic Bloch oscillations. Phys. Rev. Lett. 91, 263902 (2014).Morandotti, R., Peschel, U., Aitchison, J. S., S., E. H. & Silberberg, Y. Experimental observation of linear and nonlinear optical Bloch oscillations. Phys. Rev. Lett. 83, 4756 (1999).Battestti, R. et al. Bloch oscillations of ultracould atoms: a tool for a metrological determination of h / mRb. Phys. Rev. Lett. 92, 253001, https://doi.org/10.1103/PhysRevLett.92.253001 (2007).Sanchis-Alepuz, H., Kosevich, Y. & Sánchez-Dehesa, J. Acoustic analogue of electronic Bloch oscillations. Phys. Rev. Lett. 98, 134301, https://doi.org/10.1103/PhysRevLett.104.197402 (2007).Lanzilotti-Kimura, N. D. et al. Bloch oscillations of THz acoustic phonons in coupled nanocavity structures. Phys. Rev. Lett. 104, 197402, https://doi.org/10.1103/PhysRevLett.104.197402 (2010).Floß, J., Kamalov, A., Averbukh, I. S. & H., B. P. Observation of Bloch oscillations in molecular rotation. Phys. Rev. Lett. 115, 203002, https://doi.org/10.1103/PhysRevLett.115.203002 (2015).Gan, Q., Ding, Y. J. & Bartoli, F. Trapping and releasing at telecommunication wavelengths. Phys. Rev. Lett. 102, 056801, https://doi.org/10.1103/PhysRevLett.102.056801 (2009).Park, J., Boarman, A. D. & Hess, O. Trapping light in plasmonic waveguides. Opt. Express 18, 598–623, https://doi.org/10.1364/OE.18.000598 (2010).Zhao, D., Li, Y. & Zhu, X. Trapped rainbow effect in visible light left-handed heterostructures. Appl. Phys. Lett. 95, 071111, https://doi.org/10.1063/1.3211867 (2009).Smolyaninova, V. N., Smolyaninov, I. I., Kildishev, A. V. & Shalaev, V. Experimental observation of the trapped rainbow. Appl. Phys. Lett. 96, 211121, https://doi.org/10.1063/1.3442501 (2010).Ni, X. et al. Acoustic rainbow trapping by coiling up space. Sci. Rep. 4, 7038, https://doi.org/10.1038/srep07038 (2014).Zhu, J. et al. Acoustic rainbow trapping. Sci. Rep. 3, 1728, https://doi.org/10.1038/srep01728 (2013).Romero-García, V., Picó, R., Cebrecos, A., Sánchez-Morcillo, V. J. & Staliunas, K. 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Enhanced transmission band in periodic media with loss modulation

Copyright (2014) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in: Applied Physics Letters 105, 204104 (2014); doi: 10.1063/1.4902387 and may be found at: http://dx.doi.org/10.1063/1.490238.We study the propagation of waves in a periodic array of absorbing layers. We report an anomalous increase of wave transmission through the structure related to a decrease of the absorption around the Bragg frequencies. The effect is first discussed in terms of a generic coupled wave model extended to include losses, and its predictions can be applied to different types of waves propagating in media with periodic modulation of the losses at the wavelength scale. The particular case of sound waves in an array of porous layers embedded in air is considered. An experiment designed to test the predictions demonstrates the existence of the enhanced transmission band. (C) 2014 AIP Publishing LLC.The work was supported by Spanish Ministry of Science and Innovation and European Union FEDER through Projects FIS2011-29731-C02-01 and -02, also MAT2009-09438. A.M.Y. would like to thank the Erasmus Mundus Project (WELCOME program) for supporting him. V.R.G. acknowledges financial support from the "Pays-de-la-Loire" through the post-doctoral program.Cebrecos Ruiz, A.; Picó Vila, R.; Romero García, V.; Yasser, AM.; Maigyte, L.; Herrero, R.; Botey, M.... (2014). Enhanced transmission band in periodic media with loss modulation. Applied Physics Letters. 105(20):204104-1-204104-4. doi:10.1063/1.4902387S204104-1204104-410520Figotin, A., & Vitebskiy, I. (2008). Absorption suppression in photonic crystals. Physical Review B, 77(10). doi:10.1103/physrevb.77.104421Figotin, A., & Vitebskiy, I. (2010). Magnetic Faraday rotation in lossy photonic structures. Waves in Random and Complex Media, 20(2), 298-318. doi:10.1080/17455030.2010.482575Erokhin, S. G., Lisyansky, A. A., Merzlikin, A. M., Vinogradov, A. P., & Granovsky, A. B. (2008). Photonic crystals built on contrast in attenuation. Physical Review B, 77(23). doi:10.1103/physrevb.77.233102Kumar, N., Botey, M., Herrero, R., Loiko, Y., & Staliunas, K. (2012). High-directional wave propagation in periodic loss modulated materials. Photonics and Nanostructures - Fundamentals and Applications, 10(4), 644-650. doi:10.1016/j.photonics.2012.06.003Staliunas, K., Herrero, R., & Vilaseca, R. (2009). Subdiffraction and spatial filtering due to periodic spatial modulation of the gain-loss profile. Physical Review A, 80(1). doi:10.1103/physreva.80.013821Kumar, N., Herrero, R., Botey, M., & Staliunas, K. (2013). Flat lensing by periodic loss-modulated materials. Journal of the Optical Society of America B, 30(10), 2684. doi:10.1364/josab.30.002684Psarobas, I. E. (2001). Viscoelastic response of sonic band-gap materials. Physical Review B, 64(1). doi:10.1103/physrevb.64.012303Lee, C.-Y., Leamy, M. J., & Nadler, J. H. (2010). Frequency band structure and absorption predictions for multi-periodic acoustic composites. Journal of Sound and Vibration, 329(10), 1809-1822. doi:10.1016/j.jsv.2009.11.030Laude, V., Escalante, J. M., & Martínez, A. (2013). Effect of loss on the dispersion relation of photonic and phononic crystals. Physical Review B, 88(22). doi:10.1103/physrevb.88.224302Hwan Oh, J., Jae Kim, Y., & Young Kim, Y. (2013). Wave attenuation and dissipation mechanisms in viscoelastic phononic crystals. Journal of Applied Physics, 113(10), 106101. doi:10.1063/1.4795285Hussein, M. I. (2009). Theory of damped Bloch waves in elastic media. Physical Review B, 80(21). doi:10.1103/physrevb.80.212301Andreassen, E., & Jensen, J. S. (2013). Analysis of Phononic Bandgap Structures With Dissipation. Journal of Vibration and Acoustics, 135(4). doi:10.1115/1.4023901Allard, J. F., & Atalla, N. (2009). Propagation of Sound in Porous Media. doi:10.1002/9780470747339Tournat, V., Pagneux, V., Lafarge, D., & Jaouen, L. (2004). Multiple scattering of acoustic waves and porous absorbing media. Physical Review E, 70(2). doi:10.1103/physreve.70.026609Umnova, O., Attenborough, K., & Linton, C. M. (2006). Effects of porous covering on sound attenuation by periodic arrays of cylinders. The Journal of the Acoustical Society of America, 119(1), 278-284. doi:10.1121/1.2133715Romero-García, V., Sánchez-Pérez, J. V., & Garcia-Raffi, L. M. (2010). Evanescent modes in sonic crystals: Complex dispersion relation and supercell approximation. Journal of Applied Physics, 108(4), 044907. doi:10.1063/1.3466988Christensen, J., Romero-García, V., Picó, R., Cebrecos, A., de Abajo, F. J. G., Mortensen, N. A., … Sánchez-Morcillo, V. J. (2014). Extraordinary absorption of sound in porous lamella-crystals. Scientific Reports, 4(1). doi:10.1038/srep04674Kogelnik, H., & Shank, C. V. (1972). Coupled‐Wave Theory of Distributed Feedback Lasers. Journal of Applied Physics, 43(5), 2327-2335. doi:10.1063/1.166149

Clinical efficacy of β-lactam/β-lactamase inhibitor combinations for the treatment of bloodstream infection due to extended-spectrum β-lactamase-producing Enterobacteriaceae in haematological patients with neutropaenia: a study protocol for a retrospective observational study (BICAR)

Introduction: Bloodstream infection (BSI) due to extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-GNB) is increasing at an alarming pace worldwide. Although β-lactam/β-lactamase inhibitor (BLBLI) combinations have been suggested as an alternative to carbapenems for the treatment of BSI due to these resistant organisms in the general population, their usefulness for the treatment of BSI due to ESBL-GNB in haematological patients with neutropaenia is yet to be elucidated. The aim of the BICAR study is to compare the efficacy of BLBLI combinations with that of carbapenems for the treatment of BSI due to an ESBL-GNB in this population. Methods and analysis: A multinational, multicentre, observational retrospective study. Episodes of BSI due to ESBL-GNB occurring in haematological patients and haematopoietic stem cell transplant recipients with neutropaenia from 1 January 2006 to 31 March 2015 will be analysed. The primary end point will be case-fatality rate within 30 days of onset of BSI. The secondary end points will be 7-day and 14-day case-fatality rates, microbiological failure, colonisation/infection by resistant bacteria, superinfection, intensive care unit admission and development of adverse events. Sample size: The number of expected episodes of BSI due to ESBL-GNB in the participant centres will be 260 with a ratio of control to experimental participants of 2. Ethics and dissemination: The protocol of the study was approved at the first site by the Research Ethics Committee (REC) of Hospital Universitari de Bellvitge. Approval will be also sought from all relevant RECs. Any formal presentation or publication of data from this study will be considered as a joint publication by the participating investigators and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE). The study has been endorsed by the European Study Group for Bloodstream Infection and Sepsis (ESGBIS) and the European Study Group for Infections in Compromised Hosts (ESGICH)

Co-infections and superinfections complicating COVID-19 in cancer patients: A multicentre, international study

Background: We aimed to describe the epidemiology, risk factors, and clinical outcomes of co-infections and superinfections in onco-hematological patients with COVID-19. Methods: International, multicentre cohort study of cancer patients with COVID-19. All patients were included in the analysis of co-infections at diagnosis, while only patients admitted at least 48 h were included in the analysis of superinfections. Results: 684 patients were included (384 with solid tumors and 300 with hematological malignancies). Co-infections and superinfections were documented in 7.8% (54/684) and 19.1% (113/590) of patients, respectively. Lower respiratory tract infections were the most frequent infectious complications, most often caused by Streptococcus pneumoniae and Pseudomonas aeruginosa. Only seven patients developed opportunistic infections. Compared to patients without infectious complications, those with infections had worse outcomes, with high rates of acute respiratory distress syndrome, intensive care unit (ICU) admission, and case-fatality rates. Neutropenia, ICU admission and high levels of C-reactive protein (CRP) were independent risk factors for infections. Conclusions: Infectious complications in cancer patients with COVID-19 were lower than expected, affecting mainly neutropenic patients with high levels of CRP and/or ICU admission. The rate of opportunistic infections was unexpectedly low. The use of empiric antimicrobials in cancer patients with COVID-19 needs to be optimized

Broadband acoustic attenuation with multiresonant lossy three- dimensional sonic crystal for the train noise reduction.

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