Sensor Technologies for Intelligent Transportation Systems

Modern society faces serious problems with transportation systems, including but not limited to traffic congestion, safety, and pollution. Information communication technologies have gained increasing attention and importance in modern transportation systems. Automotive manufacturers are developing in-vehicle sensors and their applications in different areas including safety, traffic management, and infotainment. Government institutions are implementing roadside infrastructures such as cameras and sensors to collect data about environmental and traffic conditions. By seamlessly integrating vehicles and sensing devices, their sensing and communication capabilities can be leveraged to achieve smart and intelligent transportation systems. We discuss how sensor technology can be integrated with the transportation infrastructure to achieve a sustainable Intelligent Transportation System (ITS) and how safety, traffic control and infotainment applications can benefit from multiple sensors deployed in different elements of an ITS. Finally, we discuss some of the challenges that need to be addressed to enable a fully operational and cooperative ITS environment

Análisis de desempeño de estándar 802.11p en situaciones de handoff dentro de un entorno de redes vehículares.

En los últimos años un grupo de trabajo del IEEE está definiendo un nuevo estándar de comunicaciones, el cual es conocido como 802.11p, para su uso futuro en redes vehiculares ad-hoc (VANET), tanto en el formato de vehículo a vehículo (V2V) como en vehículo a infraestructura (V2I). En este artículo, nos enfocamos en un entorno de comunicación V2I, en específico se analiza el desempeño del estándar 802.11p en situaciones de traspaso (handoff). Los resultados muestran el impacto que tiene la velocidad de movimiento en el desempeño del estándar 802.11p a través de la evaluación de métricas como la cantidad de paquetes perdidos, retardo medio y tasa de transferencia asignada a las aplicaciones en entornos de redes vehiculares, lo que podría impactar a las aplicaciones implementadas dentro de este nuevo entorno.Postprint (published version

The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity

The purpose of this study is to test the role that parasympathetic postganglionic neurons could play on the adaptive electrophysiological changes produced by physical training on intrinsic myocardial automatism, conduction and refractoriness. Trained rabbits were submitted to aphysical training protocol on treadmill during 6 weeks. The electrophysiological study was performed in an isolated heart preparation. The investigated myocardial properties were: (a) sinus automatism, (b) atrioventricular and ventriculoatrial conduction, (c) atrial, conduction system and ventricular refractoriness. The parameters to study the refractoriness were obtained by means of extrastimulus test at four diVerent pacing cycle lengths (10% shorter than spontaneous sinus cycle length, 250, 200 and 150 ms) and (d) mean dominant frequency (DF) of the induced ventricular Wbrillation (VF), using a spectral method. The electrophysiological protocol was performed before and during continuous atropine administration (1 ¿M), in order to block cholinergic receptors. Cholinergic receptor blockade did not modify either the increase in sinus cycle length, atrioventricular conduction and refractoriness (left ventricular and atrioventricular conduction system functional refractory periods) or the decrease of DF of VF. These Wndings reveal that the myocardial electrophysiological modiWcations produced by physical training are not mediated by intrinsic cardiac parasympathetic activity.The authors thank Carmen Rams, Ana Diaz, Pilar Navarro and Cesar Avellaneda for their excellent technical assistance. This work has been supported by grants from the Spanish Ministry of Education and Science (DEP2007-73234-C03-01) and Generalitat Valenciana (PROMETEO 2010/093). M Zarzoso was supported by a research scholarship from Generalitat Valenciana (BFPI/2008/003).Zarzoso Muñoz, M.; Such Miquel, L.; Parra Giraldo, G.; Brines Ferrando, L.; Such, L.; Chorro, F.; Guerrero, J.... (2012). The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity. European Journal of Applied Physiology. 112(6):2185-2193. https://doi.org/10.1007/s00421-011-2189-4S218521931126Armour JA, Hopkins DA (1990a) Activity of in vivo canine ventricular neurons. Am J Physiol Heart Circ Physiol 258:H326–H336. doi: 10.1152/ajpregu.00183.2004Armour JA, Hopkins DA (1990b) Activity of canine in situ left atrial ganglion neurons. Am J Physiol Heart Circ Physiol 259:H1207–H1215Armour JA (2004) Cardiac neuronal hierarchy in health and disease. Am J Physiol Regul Integr Comp Physiol 287:R262–R271Armour JA, Murphy DA, Yuan BX, Macdonald S, Hopkins DA (1997) Gross and microscopic anatomy of the human intrinsic cardiac nervous system. Anat Rec 247:289–298Bedford TG, Tipton CM (1987) Exercise training and the arterial baroreflex. J Appl Physiol 63:1926–1932Bonaduce D, Petretta M, Cavallaro V, Apicella C, Ianniciello A, Romano M, Breglio R, Marciano F (1998) Intensive training and cardiac autonomic control in high level athletes. Med Sci Sports Exerc 30:691–696Brack KE, Coote JH, Ng GA (2011) Vagus nerve stimulation protects against ventricular fibrillation independent of muscarinic receptor activation. Cardiovasc Res 91:437–446. doi: 10.1093/cvr/cvr105Brorson L, Conradson TB, Olsson B, Varnauskas E (1976) Right atrial monophasic action potential and effective refractory periods in relation to physical training and maximal heart rate. Cardiovasc Res 10:160–168Carmeliet E, Mubagwa K (1998) Antiarrhythmic drugs and cardiac ion channels: mechanisms of action. Prog Biophys Mol Biol 70:1–72Chorro FJ, Cánoves J, Guerrero J, Mainar L, Sanchis J, Such L, López-Merino V (2000) Alteration of ventricular fibrillation by flecainide, verapamil, and sotalol: an experimental study. Circulation 101:1606–1615Di Carlo SE, Bishop VS (1990) Exercise training enhances cardiac afferent inhibition of baroreflex function. Am J Physiol 258:212–220Gagliardi M, Randall WC, Bieger D, Wurster RD, Hopkins DA, Armour JA (1988) Activity of in vivo canine cardiac plexus neurons. Am J Physiol Heart Circ Physiol 255:H789–H800Gao L, Wang W, Liu D, Zucker IH (2007) Exercise training normalizes sympathetic outflow by central antioxidant mechanisms in rabbits with pacing-induced chronic heart failure. Circulation 115:3095–3102. doi: 10.1161/CIRCULATIONAHA.106.677989Gaustad SE, Rolim N, Wisløff U (2010) A valid and reproducible protocol for testing maximal oxygen uptake in rabbits. Eur J Cardiovasc Prev Rehabil 17:83–88. doi: 10.1097/HJR.0b013e32833090c4Gómez-Cabrera MC, Borrás C, Pallardó FV, Sastre J, Ji LL, Viña J (2005) Decreasing xanthine oxidase-mediated oxidative stress prevents useful cellular adaptations to exercise in rats. J Physiol 567:113–120. doi: 10.1113/jphysiol.2004.080564Gray AL, Johnson TA, Ardell JL, Massari VJ (2004) Parasympathetic control of the heart II. A novel interganglionic intrinsic cardiac circuit mediates neural control of heart rate. J Appl Physiol 96:2273–2278. doi: 10.1152/japplphysiolHamilton KL, Powers SK, Sugiura T, Kim S, Lennon S, Tumer N, Mehta JL (2001) Short-term exercise training can improve myocardial tolerance to I/R without elevation in heat shock proteins. Am J Physiol Heart Circ Physiol 281:1346–1352Inoue H, Zipes DP (1987) Changes in atrial and ventricular refractoriness and atrioventricular nodal conduction produced by combinations of vagal and sympathetic stimulation that result in a constant spontaneous sinus cycle length. Circ Res 60:942–951Jew KN, Olsson MC, Mokelke EA, Palmer BM, Moore RL (2001) Endurance training alters outward K+ current characteristics in rat cardiocytes. J Appl Physiol 90:1327–1333Johnson TA, Gray AL, Lauenstein JM, Newton SS, Massari VJ (2004) Parasympathetic control of the heart I. An interventriculo-septal ganglion is the major source of the vagal intracardiac innervation of the ventricles. J Appl Physiol 96:2265–2272. doi: 10.1152/japplphysiol.00620.2003Katona PG, McLean M, Dighton DH, Guz A (1982) Sympathetic and parasympathetic cardiac control in athletes and nonathletes at rest. J Appl Physiol 52:1652–1657Lewis SF, Nylander E, Gad P, Areskog N (1980) Non-autonomic component in bradycardia of endurance trained men at rest and during exercise. Acta Physiol Scand 109:297–305Litovsky SH, Antzelevitch C (1990) Differences in the electrophysiological response of canine ventricular subendocardium and subepicardium to acetylcholine and isoproterenol. A direct effect of acetylcholine in ventricular myocardium. Circ Res 67:615–627Löffelholz K (1981) Release of acetylcholine in the isolated heart. Am J Physiol 240(4):H431–H440Lopatin AN, Nichols CG (2001) Inward rectifiers in the heart: an update on I(K1). J Mol Cell Cardiol 33:625–638. doi: 10.1006/jmcc.2001.1344Mace LC, Palmer BM, Brown DA, Jew KN, Lynch JM, Glunt JM, Parsons TA, Cheung JY, Moore RL (2003) Influence of age and run training on cardiac Na+/Ca2+ exchange. J Appl Physiol 95:1994–2003. doi: 10.1152/japplphysiol.00551.2003Martins JB, Zipes DP (1980) Effects of sympathetic and vagal nerves on recovery properties of the endocardium and epicardium of the canine left ventricle. Circ Res 46:100–110Mezzani A, Giovannini T, Michelucci A, Padeletti L, Resina A, Cupelli V, Musante R (1990) Effects of training on the electrophysiologic properties of atrium and accessory pathway in athletes with Wolff–Parkinson–White syndrome. Cardiology 77:295–302Mokelke EA, Palmer BM, Cheung JY, Moore RL (1997) Endurance training does not affect intrinsic calcium current characteristics in rat myocardium. Am J Physiol Heart Circ Physiol 273:H1193–H1197Mont L, Elosua R, Brugada J (2009) Endurance sport practice as a risk factor for atrial fibrillation and atrial flutter. Europace 11:11–17. doi: 10.1093/europace/eun289Moore RL, Korzick DH (1995) Cellular adaptations of the myocardium to chronic exercise. 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J Auton Nerv Syst 20:91–101Scott AS, Eberhard A, Ofir D, Benchetrit G, Dinh TP, Calabrese P, Lesiuk V, Perrault H (2004) Enhanced cardiac vagal efferent activity does not explain training-induced bradycardia. Auton Neurosci 112:60–68. doi: 10.1016/j.autneu.2004.04.006Seals DR, Chase PB (1989) Influence of physical training on HR variability and baroreflex circulatory control. J Appl Physiol 66:1886–1895Shi X, Stevens GHJ, Foresman BH, Stern SA, Raven PB (1995) Autonomic nervous system control of the heart: endurance exercise training. Med Sci Sports Exerc 27:1406–1413Snyders DJ (1999) Structure and function of cardiac potassium channels. Cardiovasc Res 42:377–390Stein R, Moraes RS, Cavalcanti AV, Ferlin EL, Zimerman LI, Ribeiro JP (2000) Atrial automaticity and atrioventricular conduction in athletes: contribution of autonomic regulation. 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Walking Promotion in Pregnancy and Its Effects on Insomnia: Results of Walking_Preg Project (WPP) Clinical Trial

Insomnia is a frequent condition during pregnancy. The aim of this study was to assess if a walking promotion program from the 12th GestationalWeek (GW) of pregnancy helps to prevent insomnia and improve the quality of sleep at third trimester. Materials and Methods: A prospective, randomized, and controlled trial was conducted with 270 pregnant women divided into 3 groups in parallel: maximum intervention group, I1 (pedometer and goal of 10,000 steps/day), minimum intervention group, I2 (pedometer without a goal), and control group (no intervention). All groups received recommendations about physical activity in pregnancy. A structured interview was performed at 13th, 20th, and 32nd GW, collecting pedometer mean steps/day, Athens Insomnia Scale (AIS), and Pittsburgh questionnaire (PSQI). Lineal regression models were conducted to determine the association between mean steps/day at 31st GW and AIS or PSQI score. Results: At 19th GW, groups I1 and I2 reached a mean of 6267 steps/day (SD = 3854) and 5835 steps/day (SD = 2741), respectively (p > 0.05). At 31st GW mean steps/day was lower for I2 (p < 0.001). Insomnia and poor sleep quality prevalence increased through pregnancy, but no differences between groups, within trimesters, were found (p > 0.05). Lineal regression showed no association between the average steps/day at third trimester of pregnancy and AIS and PSQI scores. Conclusions: Our walking promotion program based on pedometers did not help to prevent insomnia in the third trimester of pregnancy.FIBAO (Fundacion para la Investigacion Biosanitaria de Andalucia Oriental-Alejandro Otero) PI-0350-201

Biodegradable FeMnSi sputter-coated macroporous polypropylene membranes for the sustained release of drugs

Pure Fe and FeMnSi thin films were sputtered on macroporous polypropylene (PP) membranes with the aim to obtain biocompatible, biodegradable and, eventually, magnetically-steerable platforms. Room-temperature ferromagnetic response was observed in both Fe- and FeMnSi-coated membranes. Good cell viability was observed in both cases by means of cytotoxicity studies, though the FeMnSi-coated membranes showed higher biodegradability than the Fe-coated ones. Various strategies to functionalize the porous platforms with transferrin-Alexa Fluor 488 (Tf-AF488) molecules were tested to determine an optimal balance between the functionalization yield and the cargo release. The distribution of Tf-AF488 within the FeMnSi-coated PP membranes, as well as its release and uptake by cells, was studied by confocal laser scanning microscopy. A homogeneous distribution of the drug within the membrane skeleton and its sustained release was achieved after three consecutive impregnations followed by the addition of a layer made of gelatin and maltodextrin, which prevented exceedingly fast release. The here-prepared organic-inorganic macroporous membranes could find applications as fixed or magnetically-steerable drug delivery platforms

A novel learning environment for undergraduate mathematics courses

This work presents a scaffolding design of learning objects as auxiliaries in the teaching-learning of mathematics at undergraduate level, through an electronic learning platform developed for using in formal mathematics courses. Its design is based on the results of surveying a group of mathematics teachers in the undergraduate fields of Science and Engineering in Mexico, about different aspects of their teaching practice. This survey is consistent with other national and international studies that highlight a series of problems found in the undergraduate fields of Science and Engineering. Guidelines for the development of this kind of &nbsp;learning objects were established, which leads to curricular changes that will result in an adequate process of integrating the use of technology in the classroom. An important feature of these objects is flexibility as they are helpful tools in the innovative design process. A grounded model for the creation of teaching materials is proposed, including elements that facilitate their use, and thus, it is concluded that the use of these tools is a factor that can help alleviate some of the learning problems currently present in undergraduate level mathematics courses.&nbsp

Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

[EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. 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(2011). The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity. European Journal of Applied Physiology, 112(6), 2185-2193. doi:10.1007/s00421-011-2189-4Billman, G. E. (2009). Cardiac autonomic neural remodeling and susceptibility to sudden cardiac death: effect of endurance exercise training. American Journal of Physiology-Heart and Circulatory Physiology, 297(4), H1171-H1193. doi:10.1152/ajpheart.00534.2009HAN, J., & MOE, G. K. (1964). Nonuniform Recovery of Excitability in Ventricular Muscle. Circulation Research, 14(1), 44-60. doi:10.1161/01.res.14.1.44Beaumont, E., Salavatian, S., Southerland, E. M., Vinet, A., Jacquemet, V., Armour, J. A., & Ardell, J. L. (2013). Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function. The Journal of Physiology, 591(18), 4515-4533. doi:10.1113/jphysiol.2013.259382Armour, J. 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Exosomes as Hedgehog carriers in cytoneme-mediated transport and secretion

The Hedgehog signalling pathway is crucial for development, adult stem cell maintenance, cell migration and axon guidance in a wide range of organisms. During development, the Hh morphogen directs tissue patterning according to a concentration gradient. Lipid modifications on Hh are needed to achieve graded distribution, leading to debate about how Hh is transported to target cells despite being membrane-tethered. Cytonemes in the region of Hh signalling have been shown to be essential for gradient formation, but the carrier of the morphogen is yet to be defined. Here we show that Hh and its co-receptor Ihog are in exovesicles transported via cytonemes. These exovesicles present protein markers and other features of exosomes. Moreover, the cell machinery for exosome formation is necessary for normal Hh secretion and graded signalling. We propose Hh transport via exosomes along cytonemes as a significant mechanism for the restricted distribution of a lipid-modified morphogen.PostprintPeer reviewe

Newly developed Learning and Verbal Memory Test (TAMV-I): Normative data for Spanish-speaking pediatric population

OBJECTIVE: To generate normative data for the Learning and Verbal Memory Test (TAMV-I) in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the TAMV-I as part of a larger neuropsychological battery. Free recall, memory delay and recognition scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models indicated main effects for age on all scores, such that scores increased linearly as a function of age. Age2 had a significant effect in all countries except Cuba, and Puerto Rico for free recall score; a significant effect for memory delay score in all countries except Cuba and Puerto Rico; and a significant effect for recognition score in in all countries except Guatemala, Honduras, and Puerto Rico. Models showed an effect for MLPE in Chile (free recall), Honduras (free recall), Mexico (free recall), Puerto Rico (free recall, memory delay, and recognition), and Spain (free recall and memory delay). Sex affected free recall score for Cuba, Ecuador, Guatemala, Mexico, Paraguay, Peru, and Spain, memory delay score for all countries except Chile, Paraguay, and Puerto Rico, and recognition score for Ecuador, Mexico, Peru, and Spain, with girls scoring higher than boys. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate way to interpret the TAMV-I with pediatric populations

Stroop Color-Word Interference Test: Normative data for Spanish-speaking pediatric population

OBJECTIVE: To generate normative data for the Stroop Word-Color Interference test in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the Stroop Word-Color Interference test as part of a larger neuropsychological battery. The Stroop Word, Stroop Color, Stroop Word-Color, and Stroop Interference scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models showed main effects for age on all scores, except on Stroop Interference for Guatemala, such that scores increased linearly as a function of age. Age2 affected Stroop Word scores for all countries, Stroop Color scores for Ecuador, Mexico, Peru, and Spain; Stroop Word-Color scores for Ecuador, Mexico, and Paraguay; and Stroop Interference scores for Cuba, Guatemala, and Spain. MLPE affected Stroop Word scores for Chile, Mexico, and Puerto Rico; Stroop Color scores for Mexico, Puerto Rico, and Spain; Stroop Word-Color scores for Ecuador, Guatemala, Mexico, Puerto Rico and Spain; and Stroop-Interference scores for Ecuador, Mexico, and Spain. Sex affected Stroop Word scores for Spain, Stroop Color scores for Mexico, and Stroop Interference for Honduras. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate approach to interpret the Stroop Word-Color Interference test in pediatric populations