Promising Practices: The Importance of Outreach to Underserved Populations

Underserved groups have been handicapped by barriers that have resulted in low participation rates in the job market, especially if they have a physical or mental disability. It is often times difficult to get the attention of these underserved groups without making extraordinary efforts to reach out to their communities. Understanding the barriers that cause the low participation in our programs is the first step in removing these barriers. This overview is not intended to be all-inclusive, but simply to discuss a few of the barriers that have caused this lack of participation and how specific projects have taken steps to address them

Time and frequency pump-probe multiplexing to enhance the signal response of Brillouin optical time-domain analyzers

© 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 prohibitedA technique to enhance the response and performance of Brillouin distributed fiber sensors is proposed and experimentally validated. The method consists in creating a multi-frequency pump pulse interacting with a matching multi-frequency continuous-wave probe. To avoid nonlinear cross-interaction between spectral lines, the method requires that the distinct pump pulse components and temporal traces reaching the photodetector are subject to wavelength-selective delaying. This way the total pump and probe powers launched into the fiber can be incrementally boosted beyond the thresholds imposed by nonlinear effects. As a consequence of the multiplied pump-probe Brillouin interactions occurring along the fiber, the sensor response can be enhanced in exact proportion to the number of spectral components. The method is experimentally validated in a 50 km-long distributed optical fiber sensor augmented to 3 pump-probe spectral pairs, demonstrating a signal-to-noise ratio enhancement of 4.8 dB.The authors would like to thank Mr. Javier Urricelqui from Universidad Publica de Navarra (Spain) for the valuable discussions and help in relation to the noise characteristics of BOTDA sensors. This work was performed in the framework and with the support of the COST Action TD1001 OFSeSa. M. A. Soto and L. Thevenaz acknowledge the support from the Swiss Commission for Technology and Innovation (Project 13122.1), and from the Swiss State Secretariat for Education, Research and Innovation (SERI) through the project COST C10.0093. UPVLC group acknowledges the support from the Spanish MICINN and the Valencia Government through the projects TEC2011-29120-C05-05 and ACOMP/2013/146, respectively. L. Zhang acknowledges the support from the China Scholarship Council during his stay at EPFL in Switzerland.Soto, MA.; Ricchiuti, AL.; Zhang, L.; Barrera Vilar, D.; Sales Maicas, S.; Thevenaz, L. (2014). Time and frequency pump-probe multiplexing to enhance the signal response of Brillouin optical time-domain analyzers. Optics Express. 22(23):28584-28595. https://doi.org/10.1364/OE.22.028584S28584285952223Horiguchi, T., Shimizu, K., Kurashima, T., Tateda, M., & Koyamada, Y. (1995). Development of a distributed sensing technique using Brillouin scattering. Journal of Lightwave Technology, 13(7), 1296-1302. doi:10.1109/50.400684Soto, M. A., & Thévenaz, L. (2013). Modeling and evaluating the performance of Brillouin distributed optical fiber sensors. Optics Express, 21(25), 31347. doi:10.1364/oe.21.031347Foaleng, S. M., & Thévenaz, L. (2011). Impact of Raman scattering and modulation instability on the performances of Brillouin sensors. 21st International Conference on Optical Fiber Sensors. doi:10.1117/12.885105Alem, M., Soto, M. A., & Thévenaz, L. (2014). Modelling the depletion length induced by modulation instability in distributed optical fibre sensors. 23rd International Conference on Optical Fibre Sensors. doi:10.1117/12.2058862Thévenaz, L., Mafang, S. F., & Lin, J. (2013). Effect of pulse depletion in a Brillouin optical time-domain analysis system. Optics Express, 21(12), 14017. doi:10.1364/oe.21.014017Minardo, A., Bernini, R., & Zeni, L. (2009). A Simple Technique for Reducing Pump Depletion in Long-Range Distributed Brillouin Fiber Sensors. IEEE Sensors Journal, 9(6), 633-634. doi:10.1109/jsen.2009.2019372Soto, M. A., Bolognini, G., Di Pasquale, F., & Thévenaz, L. (2010). Simplex-coded BOTDA fiber sensor with 1 m spatial resolution over a 50 km range. Optics Letters, 35(2), 259. doi:10.1364/ol.35.000259Soto, M. A., Bolognini, G., & Di Pasquale, F. (2010). Analysis of pulse modulation format in coded BOTDA sensors. Optics Express, 18(14), 14878. doi:10.1364/oe.18.014878Rodriguez-Barrios, F., Martin-Lopez, S., Carrasco-Sanz, A., Corredera, P., Ania-Castanon, J. D., Thevenaz, L., & Gonzalez-Herraez, M. (2010). Distributed Brillouin Fiber Sensor Assisted by First-Order Raman Amplification. Journal of Lightwave Technology, 28(15), 2162-2172. doi:10.1109/jlt.2010.2051141Martin-Lopez, S., Alcon-Camas, M., Rodriguez, F., Corredera, P., Ania-Castañon, J. D., Thévenaz, L., & Gonzalez-Herraez, M. (2010). Brillouin optical time-domain analysis assisted by second-order Raman amplification. Optics Express, 18(18), 18769. doi:10.1364/oe.18.018769Soto, M. A., Bolognini, G., & Di Pasquale, F. (2011). Optimization of long-range BOTDA sensors with high resolution using first-order bi-directional Raman amplification. Optics Express, 19(5), 4444. doi:10.1364/oe.19.004444Soto, M. A., Taki, M., Bolognini, G., & Pasquale, F. D. (2012). Simplex-Coded BOTDA Sensor Over 120-km SMF With 1-m Spatial Resolution Assisted by Optimized Bidirectional Raman Amplification. IEEE Photonics Technology Letters, 24(20), 1823-1826. doi:10.1109/lpt.2012.2212183Jia, X.-H., Rao, Y.-J., Yuan, C.-X., Li, J., Yan, X.-D., Wang, Z.-N., … Peng, F. (2013). Hybrid distributed Raman amplification combining random fiber laser based 2nd-order and low-noise LD based 1st-order pumping. Optics Express, 21(21), 24611. doi:10.1364/oe.21.024611Soto, M. A., Angulo-Vinuesa, X., Martin-Lopez, S., Chin, S.-H., Ania-Castanon, J. D., Corredera, P., … Thevenaz, L. (2014). Extending the Real Remoteness of Long-Range Brillouin Optical Time-Domain Fiber Analyzers. Journal of Lightwave Technology, 32(1), 152-162. doi:10.1109/jlt.2013.2292329Soto, M. A., Bolognini, G., & Pasquale, F. D. (2009). Distributed optical fibre sensors based on spontaneous Brillouin scattering employing multimode Fabry-Pérot lasers. Electronics Letters, 45(21), 1071. doi:10.1049/el.2009.2381Li, C., Wang, F., Lu, Y., & Zhang, X. (2012). SNR enhancement in Brillouin optical time domain reflectometer using multi-wavelength coherent detection. Electronics Letters, 48(18), 1139-1141. doi:10.1049/el.2012.1248Voskoboinik, A., Wang, J., Shamee, B., Nuccio, S. R., Zhang, L., Chitgarha, M., … Tur, M. (2011). SBS-Based Fiber Optical Sensing Using Frequency-Domain Simultaneous Tone Interrogation. Journal of Lightwave Technology, 29(11), 1729-1735. doi:10.1109/jlt.2011.2145411Voskoboinik, A., Yilmaz, O. F., Willner, A. W., & Tur, M. (2011). Sweep-free distributed Brillouin time-domain analyzer (SF-BOTDA). Optics Express, 19(26), B842. doi:10.1364/oe.19.00b842Chaube, P., Colpitts, B. G., Jagannathan, D., & Brown, A. W. (2008). Distributed Fiber-Optic Sensor for Dynamic Strain Measurement. IEEE Sensors Journal, 8(7), 1067-1072. doi:10.1109/jsen.2008.926107Nikles, M., Thevenaz, L., & Robert, P. A. (1997). Brillouin gain spectrum characterization in single-mode optical fibers. Journal of Lightwave Technology, 15(10), 1842-1851. doi:10.1109/50.633570Jacobs, I. (1995). Dependence of optical amplifier noise figure on relative-intensity-noise. Journal of Lightwave Technology, 13(7), 1461-1465. doi:10.1109/50.400712Bolognini, G., Soto, M. A., & Di Pasquale, F. (2009). Fiber-Optic Distributed Sensor Based on Hybrid Raman and Brillouin Scattering Employing Multiwavelength Fabry–PÉrot Lasers. IEEE Photonics Technology Letters, 21(20), 1523-1525. doi:10.1109/lpt.2009.202889

A framework for the standardisation of tropical tuna purse seine CPUE: application to the yellowfin tuna in the Indian Ocean

We revised the existing framework for tuna CPUE standardisation in light of the increasing literature that advocates the use of mixed effects models to account for the characteristics of logbook data. We apply the framework on yellowfin tuna (YFT) from the Indian Ocean, caught by the purse seine EU fleet (Spain and France) from 1984 to 2015. We used a comprehensive list of candidate covariates, including non- conventional covariates, and run exploratory models to assess the contribution of each covariate. Due to the large number of covariates, the lasso – least absolute shrinkage and selection operator- method was applied for data mining and model selection purposes. The results are two standardised YFT CPUE time series for the period 1984-2015, one for large fish caught in free-school related sets, and one for mainly juveniles caught in floating object related sets. Issues on the usefulness of highly aggregated data (low resolution: annual and fleet wide) is discussed along with the need for more detailed information on the use of dFADs, preferably at the level of a fishing trip.Preprin

Home-Based Exercise in Elderly Patients with Claudication and Chronic Kidney Disease Is Associated with Lower Progressive Renal Function Worsening: A 5-Year Retrospective Study

This observational study aimed to monitor the 5-year trends of kidney function in patients with peripheral artery disease (PAD) and concomitant chronic kidney disease (CKD) enrolled or not enrolled into a rehabilitative exercise program. Sixty-six patients (aged 72 ± 10, males n = 52) at KDOQI stages III-IV and PAD at Rutherford’s stage I-III were included in the study, with a group (Exercise, EX; n = 32) receiving a 6-month structured pain-free home-based walking program and a group (Control, CO; n = 34) receiving walking advice and optimal nephrological care. Outcomes included kidney function measured through serum creatinine (sCr) and clinical outcomes, including the rate of advance of CKD stages and admission to dialysis, revascularizations, and hospitalizations. At baseline, the two groups were comparable for age, nephropathy, medications, comorbidities, and PAD severity. Patients in the EX group safely completed the exercise program. SCr values were slightly increased in EX (baseline: 2.35 ± 0.32; 5-year: 2.71 ± 0.39 mg/dL) and progressively worsened in CO (baseline: 2.30 ± 0.31; 5-year 4.22 ± 0.42 mg/dL), with a significant between-group difference (p = 0.002). The control group also showed a higher number of dialysis admissions (5 vs. 0, p = 0.025) and advancing CKD stage as well a higher risks for lower limb revascularization (hazard ratio: 2.59; 95%CI: 1.11–6.02; p = 0.027) and for all-cause hospitalization (hazard ratio: 1.77; 95%CI: 1.05–2.97; p = 0.031). PAD-CKD patients enrolled in a low-moderate intensity home-exercise program showed more favorable long-term trends in kidney function and clinical outcomes than patients with usual care. These preliminary observations need to be confirmed in randomized trials

Distributed acoustic sensing for seismic activity monitoring

Continuous, real-time monitoring of surface seismic activity around the globe is of great interest for acquiring new insight into global tomography analyses and for recognition of seismic patterns leading to potentially hazardous situations. The already-existing telecommunication fiber optic network arises as an ideal solution for this application, owing to its ubiquity and the capacity of optical fibers to perform distributed, highly sensitive monitoring of vibrations at relatively low cost (ultra-high density of point sensors available with minimal deployment of new equipment). This perspective article discusses early approaches on the application of fiber-optic distributed acoustic sensors (DASs) for seismic activity monitoring. The benefits and potential impact of DAS technology in these kinds of applications are here illustrated with new experimental results on teleseism monitoring based on a specific approach: the so-called chirped-pulse DAS. This technology offers promising prospects for the field of seismic tomography due to its appealing properties in terms of simplicity, consistent sensitivity across sensing channels, and robustness. Furthermore, we also report on several signal processing techniques readily applicable to chirped-pulse DAS recordings for extracting relevant seismic information from ambient acoustic noise. The outcome presented here may serve as a foundation for a novel conception for ubiquitous seismic monitoring with minimal investment

Ambulatory blood pressure monitoring during pregnancy: an Italian experience

Objective: To describe the impact of a collaborative Italian diagnostic pathway offering ambulatory blood pressure (BP) monitoring (ABPM) in High Risk Antenatal Clinic (HRAC) pregnant women. The study included 395 pregnant women evaluated at HRAC between 2012 and 2016, while analyzing demographic, clinical characteristics, and prescription of ABPM. Pregnant women were firstly seen when gestational age was 19.6 +/- 9.6 weeks. In at least one-third of cases, ABPM was followed by medical intervention aiming to modify the preexisting therapeutic treatment. Hypertension and overweight were the main reasons for performing ABPM. WCH: white-coat hypertension

Distributed acoustic sensing for seismic activity monitoring

Continuous, real-time monitoring of surface seismic activity around the globe is of great interest for acquiring new insight into global tomography analyses and for recognition of seismic patterns leading to potentially hazardous situations. The already-existing telecommunication fiber optic network arises as an ideal solution for this application, owing to its ubiquity and the capacity of optical fibers to perform distributed, highly sensitive monitoring of vibrations at relatively low cost (ultra-high density of point sensors available with minimal deployment of new equipment). This perspective article discusses early approaches on the application of fiber-optic distributed acoustic sensors (DASs) for seismic activity monitoring. The benefits and potential impact of DAS technology in these kinds of applications are here illustrated with new experimental results on teleseism monitoring based on a specific approach: the so-called chirped-pulse DAS. This technology offers promising prospects for the field of seismic tomography due to its appealing properties in terms of simplicity, consistent sensitivity across sensing channels, and robustness. Furthermore, we also report on several signal processing techniques readily applicable to chirped-pulse DAS recordings for extracting relevant seismic information from ambient acoustic noise. The outcome presented here may serve as a foundation for a novel conception for ubiquitous seismic monitoring with minimal investment