Hip hop and diaspora: the significance of afro-american music in the creation of identity

Treballs Finals del Grau d'Estudis Anglesos, Facultat de Filologia, Universitat de Barcelona, Curs: 2019-2020, Tutor: Cornelis Martin Renes[eng] This essay aims to provide a look on the appropriateness to classify hip-hop as a product of Afrodiasporic oral and musical traditions. Music is a conduit which provides resistant identities to the dominant cultures. So, this essay is going to expose how reggae and blues music have been key in the development of Hip Hop and will take examples from these genres to illustrate how African Americans created identities within adverse environments through music. Finally, this paper will explore how hip-hop is a product of its context and how music reflects the difficult realities most African Americans face.[spa] Este ensayo tiene como objetivo proporcionar la idoneidad de clasificar el hip-hop como un producto de las tradiciones orales y musicales africanas. Este observará cómo la música sirve para crear identidades resistentes a las culturas dominantes. El reggae y el blues han sido clave en el desarrollo de este género y este ensayo tomará ejemplos de estos para ilustrar como los afroamericanos crearon identidades en entornos adversos. Finalmente, este artículo explorará cómo el hip-hop es un producto de su entorno y cómo la música refleja las difíciles realidades en las que se enfrentan la mayoría de los afroamericanos

Transmission Over SSMF at 850 nm: Bimodal Propagation and Equalization

[EN] The combination of 850 nm vertical-cavity surfaceemitting laser (VCSEL) with standard single-mode fiber (SSMF) presents an effective and low-cost interface to increase the reach provided by multi-mode fiber links. At 850 nm, SSMF propagates two modes, and in this study, it has been experimentally shown that the different commercially available SSMF¿s present dissimilar values of differential mode delay. To cope with this unequal behavior of modal dispersion, we propose a scheme based on bidirectional decision feedback equalization (BiDFE) to overcome limited performance of other solutions as mode filtering or classical equalizers. A single span SSMF cabling model, including a measurement-derived statistical characterization of optical connectors, is simulated to evaluate the reach provided by the equalizer attending to both the conditions of the fiber excitation and the characteristics of the VCSEL. A minimum 1.45 km link length at 10 Gb/s is achieved if a linear combining BiDFE (LC-BiDFE) equalizer is included in the receiver, whatever laser launching condition and employing a single-transverse mode VCSEL. If a multitransverse mode VCSEL is used, the reach provided by LC-BiDFE is slightly reduced but assuring a minimum coverage of 1.15 km.This work was supported by the Spanish Ministerio de Economia y Competitividad under Projects TEC2015-70858-C2-2-R and TEC2015-70858-C2-1-R, both with FEDER funds. The work of P. Medina Sevila was supported by the Formacion de Personal Investigador grant program of the Universitat Politecnica de Valencia.Medina-Sevila, P.; Almenar Terré, V.; Corral, JL. (2017). Transmission Over SSMF at 850 nm: Bimodal Propagation and Equalization. Journal of Lightwave Technology. 35(19):4125-4136. https://doi.org/10.1109/JLT.2017.2726585S41254136351

Combined data detection scheme for zero-padded OFDM signals in MMF links

© © 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this letter, we propose a receiver scheme for zero-padded orthogonal frequency division multiplexing (OFDM) that combines low complexity from overlap-and-add equalizer and low error rate provided by successive interference cancellation data detection from optimal ordering vertical Bell Laboratories layered space-time (V-BLAST) architecture. Results of numerical simulations on multimode optical fiber links show that the proposed scheme improves the error rate performance of zero forcing (ZF) equalization receiver, reaching results similar to V-BLAST. For example, the proposed scheme can reach 33.9 Gb/s in a 600-m link, whereas the ZF receiver would reach 29.06 Gb/s and cyclic prefix OFDM only 19.37 Gb/s. These results are obtained with a reduction in computational complexity (measured in number of real products) of 86% in detection and 66% in preprocessing with respect to the ZF receiver, and 75% and 97% with respect to the V-BLAST receiver.Manuscript received May 6, 2015; accepted May 24, 2015. Date of publication June 1, 2015; date of current version July 10, 2015. This work was supported by the Spanish Ministerio de Economia y Competitividad under Project TEC2012-38558-C02-02 and Project TEC2012-38558-C02-01, both with FEDER funds. The work of P. Medina was supported by the Formacion de Personal Investigador Grant Program of the Universitat Politecnica de Valencia.Medina Sevila, P.; Almenar Terré, V.; Corral, JL. (2015). Combined data detection scheme for zero-padded OFDM signals in MMF links. IEEE Photonics Technology Letters. 27(16):1753-1756. https://doi.org/10.1109/LPT.2015.2439158S17531756271

Twitching and swimming motility play a role in Ralstonia solanacearum pathogenicity

Ralstonia solanacearum is a bacterial plant pathogen causing important economic losses worldwide. In addition to the polar flagella responsible for swimming motility, this pathogen produces type IV pili (TFP) that govern twitching motility, a flagellum-independent movement on solid surfaces. The implication of chemotaxis in plant colonization, through the control flagellar rotation by the proteins CheW and CheA, has been previously reported in R. solanacearum. In this work, we have identified in this bacterium homologues of the Pseudomonas aeruginosa pilI and chpA genes, suggested to play roles in TFP-associated motility analogous to those played by the cheW and cheA genes, respectively. We demonstrate that R. solanacearum strains with a deletion of the pilI or the chpA coding region show normal swimming and chemotaxis but altered biofilm formation and reduced twitching motility, transformation efficiency, and root attachment. Furthermore, these mutants displayed wild-type growth in planta and impaired virulence on tomato plants after soil-drench inoculations but not when directly applied to the xylem. Comparison with deletion mutants for pilA and fliC encoding the major pilin and flagellin subunits, respectively showed that both twitching and swimming are required for plant colonization and full virulence. This work proves for the first time the functionality of a pilus-mediated pathway encoded by pil-chp genes in R. solanacearum, demonstrating that pilI and chpA genes are bona fide motility regulators controlling twitching motility and its three related phenotypes: virulence, natural transformation, and biofilm formation

Linear Response Modeling of High Luminous Flux Phosphor-Coated White LEDs for VLC

[EN] The widespread deployment of LEDs for illumination purposes has open the door to the use of these devices for visible light communications (VLC). Most lighting fixtures are mounted with phosphor-based white LEDs, and a driver connected to the LED is also required for VLC. This paper shows that the parasitic effects introduced by this setup change the frequency response of the intrinsic LED. A linear model to characterize the whole setup is proposed, as well as a methodology to extract its parameters. This methodology allows the designer to characterize the frequency response of LEDs without the additional difficulty of knowing the specific parasitic components introduced by the setup. The proposed model offers an accurate estimation of the slope of the LED frequency response in order to broaden the frequency range in which the model is useful to characterize and simulate VLC links. This was corroborated with the characterization of three commercial white LEDs whose measured and modeled frequency responses matched perfectly.Salvador-Llàcer, P.; Valls Coquillat, J.; Corral, JL.; Almenar Terre, V.; Canet Subiela, MJ. (2022). Linear Response Modeling of High Luminous Flux Phosphor-Coated White LEDs for VLC. Journal of Lightwave Technology. 40(12):3761-3767. https://doi.org/10.1109/JLT.2022.315090737613767401

On the Performance and Power Consumption of Bias-T Based Drivers for High Speed VLC

[EN] LED lamps have become the predominant technology for lighting thanks to their low power consumption. Recently, the joint use of these devices for lighting and data transmission has aroused interest in the research community as a future green communication technology. During this time, many of the advances developed in this area have been demonstrated with experimental setups using LED drivers based on bias-T, thanks to their ease to combine signal modulation and LED bias. This article discusses the impact of the output impedance of the bias-T driver and the driver-LED connection parasitics on the performance and energy efficiency of the VLC system. It is concluded that the output impedance of the driver not only affects energy efficiency but also modifies the frequency response and, therefore, the LED's capacity to be modulated. A low output impedance driver is shown to offer a substantial improvement in the energy efficiency of the VLC driver.Thisworkwas supported in part by MCIN/AEI/10.13039/501100011033, in part by European Union (ERDF A way of making Europe) under Grants RTI2018101658-B100 and RTI2018-101296-B-I00, and in part byMinisterio de Ciencia, Innovacion y Universidades para la Formacion de Profesorado Universitario under Grant FPU19/04648.Salvador-Llàcer, P.; Valls Coquillat, J.; Canet Subiela, MJ.; Almenar Terre, V.; Corral, JL. (2022). On the Performance and Power Consumption of Bias-T Based Drivers for High Speed VLC. Journal of Lightwave Technology. 40(18):6078-6086. https://doi.org/10.1109/JLT.2022.319093660786086401

Model and Methodology to Characterize Phosphor-Based White LED Visible Light Communication Links

[EN] LED lighting has become the standard solution for illumination purposes thanks to its energy efficiency. Nowadays, there is growing interest in the use of LEDs for data transmission to develop future-generation communication systems. The low cost and widespread deployment of phosphor-based white LEDs make them the best candidate for visible light communications (VLC), although they have a limited modulation bandwidth. This paper presents a simulation model of a VLC link based on phosphor-based white LEDs and a method to characterize the VLC setup used to perform the data transmission experiments. Specifically, the simulation model incorporates the frequency response of the LED, the noise levels coming from the lighting source and the acquisition electronics, and the attenuation due to both the propagation channel and the angular misalignment between the lighting source and the photoreceiver. In order to validate the suitability of the model for VLC, carrierless amplitude phase (CAP) and orthogonal frequency division multiplexing (OFDM) modulation signals were employed for data transmission, and simulations with the proposed model and measurements over the equivalent scenario show high agreement.This research was funded by MCIN/AEI/10.13039/501100011033; by the European Union's "ERDF A way of making Europe" grant numbers PID2021-126514OB-I00 and RTI2018-101296-B-I00; and by the Ministerio de Ciencia, Innovacion y Universidades para la Formacion de Profesorado Universitario, grant number FPU19/04648.Salvador-Llàcer, P.; Almenar Terre, V.; Corral, JL.; Valls Coquillat, J.; Canet Subiela, MJ. (2023). Model and Methodology to Characterize Phosphor-Based White LED Visible Light Communication Links. Sensors. 23(10). https://doi.org/10.3390/s23104637231

Evaluation of optical ZP-OFDM transmission performance in multimode fiber links

© 2014 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited.In this paper, the performance of Zero Padding Orthogonal Frequency Division Multiplexing (ZP-OFDM) on intensity modulationdirect detection (IM-DD) multimode fiber (MMF) links is assessed by means of numerical simulations. The performance of ZP-OFDM is compared to classical Cyclic Prefixed form of OFDM (CP-OFDM) which is known to offer a limited performance in terms of symbol recovery in subcarriers suffering severe fading. Simulations results show that ZPOFDM is able to reach 29 Gbps in 99.5% of all installed MMF links up to 600 meters compared to 14 Gbps for CP-OFDM when a 64 points fast Fourier transform (FFT) size is used. The use of ZP-OFDM makes it possible to increase the link length up to 1200 and 2400 m with a 25 Gbps data rate if the FFT sizes are increased to 128 and 256 points, respectively; whereas the CP-OFDM scheme will offer a maximum data rate of 10 Gbps in both cases. ZP-OFDM can be an alternative to adaptive loading OFDM schemes without the need of a negotiation between transmitter and receiver, reducing the system deployment complexity and increasing the flexibility in scenarios with multiple receivers. (C) 2014 Optical Society of AmericaThe work presented in this paper has been supported by the Spanish Ministerio de Economia y Competitividad under projects TEC2012-38558-C02-02 and TEC2012-38558-C02-01.Medina Sevila, P.; Almenar Terré, V.; Corral González, JL. (2014). Evaluation of optical ZP-OFDM transmission performance in multimode fiber links. Optics Express. 22(1):1008-1017. https://doi.org/10.1364/OE.22.001008S10081017221Cunningham, J. E., Beckman, D., Zheng, X., Huang, D., Sze, T., & Krishnamoorthy, A. V. (2006). PAM-4 Signaling over VCSELs with 0.13µm CMOS Chip Technology. Optics Express, 14(25), 12028. doi:10.1364/oe.14.012028Gasulla, I., & Capmany, J. (2008). 1 Tb/s·km Multimode fiber link combining WDM transmission and low-linewidth lasers. Optics Express, 16(11), 8033. doi:10.1364/oe.16.008033Xia, C., Ajgaonkar, M., & Rosenkranz, W. (2005). On the performance of the electrical equalization technique in MMF links for 10-gigabit ethernet. Journal of Lightwave Technology, 23(6), 2001-2011. doi:10.1109/jlt.2005.849920Lowery, A. J., & Armstrong, J. (2005). 10Gbit/s Multimode Fiber Link using Power-Efficient Orthogonal-Frequency-Division Multiplexing. Optics Express, 13(25), 10003. doi:10.1364/opex.13.010003Xu, J., von Hoyningen-Huene, J., Ruprecht, C., Rath, R., & Rosenkranz, W. (2013). Robust Transmission of 29-Gb/s OFDM Signal Over 1-km OM1 MMF Under Center Launching. IEEE Photonics Technology Letters, 25(2), 206-209. doi:10.1109/lpt.2012.2233729Giacoumidis, E., Jin, X. Q., Tsokanos, A., & Tang, J. M. (2010). Statistical Performance Comparisons of Optical OFDM Adaptive Loading Algorithms in Multimode Fiber-Based Transmission Systems. IEEE Photonics Journal, 2(6), 1051-1059. doi:10.1109/jphot.2010.2092422Tang, J. M., Lane, P. M., & Shore, K. A. (2006). Transmission performance of adaptively modulated optical OFDM signals in multimode fiber links. IEEE Photonics Technology Letters, 18(1), 205-207. doi:10.1109/lpt.2005.861631Jin, X. Q., Tang, J. M., Qiu, K., & Spencer, P. S. (2008). Statistical Investigations of the Transmission Performance of Adaptively Modulated Optical OFDM Signals in Multimode Fiber Links. Journal of Lightwave Technology, 26(18), 3216-3224. doi:10.1109/jlt.2008.917088Kanprachar, S., & Jacobs, I. (2003). Diversity coding for subcarrier multiplexing on multimode fibers. IEEE Transactions on Communications, 51(9), 1546-1553. doi:10.1109/tcomm.2003.816981Muquet, B., Zhengdao Wang, Giannakis, G. B., de Courville, M., & Duhamel, P. (2002). Cyclic prefixing or zero padding for wireless multicarrier transmissions? IEEE Transactions on Communications, 50(12), 2136-2148. doi:10.1109/tcomm.2002.806518Tang, J. M., & Shore, K. A. (2007). Maximizing the Transmission Performance of Adaptively Modulated Optical OFDM Signals in Multimode-Fiber Links by Optimizing Analog-to-Digital Converters. Journal of Lightwave Technology, 25(3), 787-798. doi:10.1109/jlt.2006.890457Mestdagh, D. J. G., Spruyt, P. M. P., & Biran, B. (1993). Effect of amplitude clipping in DMT-ADSL transceivers. Electronics Letters, 29(15), 1354. doi:10.1049/el:1993090

Best Treatment Option for Patients With Refractory Aggressive B-Cell Lymphoma in the CAR-T Cell Era: Real-World Evidence From GELTAMO/GETH Spanish Groups

CAR-T cell therapy; Real world evidence; B cell lymphomaTerapia con células CAR-T; Evidencia del mundo real; Linfoma de células BTeràpia amb cèl·lules CAR-T; Evidència del món real; Limfoma de cèl·lules BReal-world evidence comparing the efficacy of chimeric antigen receptor (CAR) T-cell therapy against that of the previous standard of care (SOC) for refractory large B-cell lymphoma (LBCL) is scarce. We retrospectively collected data from patients with LBCL according to SCHOLAR-1 criteria treated with commercial CAR T-cell therapy in Spain (204 patients included and 192 treated, 101 with axicabtagene ciloleucel [axi-cel], and 91 with tisagenlecleucel [tisa-cel]) and compared the results with a historical refractory population of patients (n = 81) obtained from the GELTAMO-IPI study. We observed superior efficacy for CAR-T therapy (for both axi-cel and tisa-cel) over pSOC, with longer progression-free survival (PFS) (median of 5.6 vs. 4–6 months, p ≤ 0.001) and overall survival (OS) (median of 15 vs. 8 months, p < 0.001), independently of other prognostic factors (HR: 0.59 (95% CI: 0.44–0.80); p < 0.001] for PFS, and 0.45 [(95% CI: 0.31–0.64)] for OS). Within the CAR-T cohort, axi-cel showed longer PFS (median of 7.3 versus 2.8 months, respectively, p = 0.027) and OS (58% versus 42% at 12 months, respectively, p = 0.048) than tisa-cel. These differences were maintained in the multivariable analysis. On the other hand, axi-cel was independently associated with a higher risk of severe cytokine release syndrome and neurotoxicity. Our results suggest that the efficacy of CAR-T cell therapy is superior to pSOC in the real-world setting. Furthermore, axi-cel could be superior in efficacy to tisa-cel, although more toxic, in this group of refractory patients according to SCHOLAR-1 criteria

Gastrointestinal Bleeding in Patients with Hereditary Hemorrhagic Telangiectasia: Risk Factors and Endoscopic Findings

Background: We aimed to describe risk factors for gastrointestinal (GI) bleeding and endoscopic findings in patients with hereditary hemorrhagic telangiectasia (HHT). Methods: This is a prospective study from a referral HHT unit. Endoscopic tests were performed when there was suspicion of GI bleeding, and patients were divided as follows: with, without, and with unsuspected GI involvement. Results: 67 (27.9%) patients with, 28 (11.7%) patients without, and 145 (60.4%) with unsuspected GI involvement were included. Age, tobacco use, endoglin (ENG) mutation, and hemoglobin were associated with GI involvement. Telangiectases were mostly in the stomach and duodenum, but 18.5% of patients with normal esophagogastroduodenoscopy (EGD) had GI involvement in video capsule endoscopy (VCE). Telangiectases ≤ 3 mm and ≤10 per location were most common. Among patients with GI disease, those with hemoglobin 3 mm). After a mean follow-up of 34.2 months, patients with GI involvement required more transfusions and more emergency department and hospital admissions, with no differences in mortality. Conclusions: Risk factors for GI involvement have been identified. Patients with GI involvement and severe anemia had larger telangiectases and higher ESS. VCE should be considered in patients with suspicion of GI bleeding, even if EGD is normal