Corrigendum to "Assessment of tsunami hazards for the Central American Pacific coast from southern Mexico to northern Peru" published in Nat. Hazards Earth Syst. Sci., 14, 1889–1903, 2014

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Assessment of tsunami hazards for the Central American Pacific coast from southern Mexico to northern Peru

Abstract. Central America (CA), from Guatemala to Panama, has been struck by at least 52 tsunamis between 1539 and 2013, and in the extended region from Mexico to northern Peru (denoted as ECA, Extended Central America in this paper) the number of recorded tsunamis in the same time span is more than 100, most of which were triggered by earthquakes located in the Middle American Trench that runs parallel to the Pacific coast. The most severe event in the catalogue is the tsunami that occurred on 2 September 1992 off Nicaragua, with run-up measured in the range of 5–10 m in several places along the Nicaraguan coast. The aim of this paper is to assess the tsunami hazard on the Pacific coast of this extended region, and to this purpose a hybrid probabilistic-deterministic analysis is performed, that is adequate for tsunamis generated by earthquakes. More specifically, the probabilistic approach is used to compute the Gutenberg–Richter coefficients of the main seismic tsunamigenic zones of the area and to estimate the annual rate of occurrence of tsunamigenic earthquakes and their corresponding return period. The output of the probabilistic part of the method is taken as input by the deterministic part, which is applied to calculate the tsunami run-up distribution along the coast

Second and higher-order perturbations of a spherical spacetime

The Gerlach and Sengupta (GS) formalism of coordinate-invariant, first-order, spherical and nonspherical perturbations around an arbitrary spherical spacetime is generalized to higher orders, focusing on second-order perturbation theory. The GS harmonics are generalized to an arbitrary number of indices on the unit sphere and a formula is given for their products. The formalism is optimized for its implementation in a computer algebra system, something that becomes essential in practice given the size and complexity of the equations. All evolution equations for the second-order perturbations, as well as the conservation equations for the energy-momentum tensor at this perturbation order, are given in covariant form, in Regge-Wheeler gauge.Comment: Accepted for publication in Physical Review

Mode coupling of Schwarzschild perturbations: Ringdown frequencies

Within linearized perturbation theory, black holes decay to their final stationary state through the well-known spectrum of quasinormal modes. Here we numerically study whether nonlinearities change this picture. For that purpose we study the ringdown frequencies of gauge-invariant second-order gravitational perturbations induced by self-coupling of linearized perturbations of Schwarzschild black holes. We do so through high-accuracy simulations in the time domain of first and second-order Regge-Wheeler-Zerilli type equations, for a variety of initial data sets. We consider first-order even-parity $(\ell=2,m=\pm 2)$ perturbations and odd-parity $(\ell=2,m=0)$ ones, and all the multipoles that they generate through self-coupling. For all of them and all the initial data sets considered we find that ---in contrast to previous predictions in the literature--- the numerical decay frequencies of second-order perturbations are the same ones of linearized theory, and we explain the observed behavior. This would indicate, in particular, that when modeling or searching for ringdown gravitational waves, appropriately including the standard quasinormal modes already takes into account nonlinear effects

ANALYSIS OF TETHERED SWIMMING FORCE, TETHERED SWIMMING POWER, SWIMMING SPEED AND ANTROPOMETRICAL CHARACTERISTICS OF YOUNG SWIMMERS IN CRAWL STROKE

Propulsive forces, instantaneous power and swimming velocity in semi-tethered swimming were measured in a group of 69 competitive swimmers. Also, isometric force in laboratory, best 15 m swimming velocity and 100 m freestyle personal mark and anthropometric characteristics were recorded. The results show the high relationship between swimming speed and the propulsive forces, and the instantaneous power. Consequently, the above mentioned variables can be useful for the evaluation of the swimmers along a season

Applicability of the Decision Matrix of North Eastern Atlantic, Mediterranean and connected seas Tsunami Warning System to the Italian tsunamis

After the 2004 Indian Ocean tsunami catastrophe, UNESCO through the IOC (Intergovernmental Oceanographic Commission) sponsored the establishment of Intergovernmental Coordination Groups (ICG) with the aim to devise and implement Tsunami Warning Systems (TWSs) in all the oceans exposed to tsunamis, in addition to the one already in operation in the Pacific (PTWS). In this context, since 2005 efforts started for the establishment of TWSs in the Indian Ocean (IOTWS), in the Caribbean area (CARIBE EWS) and in the North Eastern Atlantic, the Mediterranean and Connected Seas (NEAMTWS). In this paper we focus on a specific tool that was first introduced in the PTWS routine operations, i.e. the Decision Matrix (DM). This is an easy-to-use table establishing a link between the main parameters of an earthquake and the possible ensuing tsunami in order to make quick decision on the type of alert bulletins that a Tsunami Warning Center launches to its recipients. In the process of implementation of a regional TWS for the NEAM area, two distinct DMs were recently proposed by the ICG/NEAMTWS, one for the Atlantic and the other for the entire Mediterranean area. This work applies the Mediterranean NEAMTWS DM to the earthquakes recorded in Italy and compares the action predicted by the DM vs. the action that should be appropriate in view of the observed tsunami characteristics with the aim to establish how good the performance of the Italian TWS will be when it uses the DM for future events. To this purpose, we make use of the parametric catalogue of the Italian earthquakes (CPTI04) compiled in 2004 and the most recent compilation of the Italian tsunami, based on the Italian Tsunami Catalogue of 2004 and the subsequent revisions. In order to better compare the TWS actions we have identified four different kinds of action coding them from 0 to 3 according to the tsunami severity and have further considered three different distance ranges where these actions apply, that is local, regional and basin-wide, that refer to the distance of the message recipients from the tsunami source. The result of our analysis is that the actions prescribed by the DM are adequate only in 45%-55% of the cases, overestimations are about 37% and underestimations are the rest. As a whole, the predictive ability of the DM is not satisfactory, which implies that recipients have the difficult task to manage bulletins carrying a great deal of uncertainty and on the other hand also suggests that strategies to improve the DM or to go beyond the DM need to be found

Creating The Learning Environment for Limited English Proficient Students Online

When offering online program options for higher education students, one of the primary concerns for institutions of higher learning program administrators is achieving high quality learning experiences for students. To achieve this goal, faculty must understand how to employ new and innovative technologies in a manner that ensures all students have positive learning outcomes. Limited English Proficiency (LEP) students are not missing in this equation. Institutions offering online courses have discerned that developing these courses requires an understanding of technologies with which many faculty are unfamiliar. As a result, administrators must create pedagogical models that enable educators to capitalize on the potentials afforded by online learning technologies to best meet the needs of all students (Norton and Hathaway, 2008) by providing quality professional development which ensures an understanding of how to use technologies effectively and how to develop a sense of instructor presence. The current case study deals with the analysis of practice within a graduate online program at a small private college in the Midwestern region of the United States. Specific identification of practices is identified via pattern recognition related to mentoring and facilitation of best practice within the online program to meet the needs of the LEP student. The foundation of all good teaching at the college level is based on specific assumptions of effective teachers (Bain, 2004)

INFLUENCE OF FOOTWEAR ON THE ANKL SPRAIN PRODUCTION MECHANISM IN BASKETBALL

INTRODUCTION: Vertical jump is a usual movement pattern in basketball, and it is related to ankle injuries, mainly during rebound actions when falling on another player's foot. The aim of the present study IS to determine the influence of the introduction of certain elements in the footwear on ankle protection when falling on an irregular surface. The study consisted in simulating a rebound action in which the player jumps and falls on an irregular surface, simulated by a 20" inclined plane. 12 footwear prototypes were studied, making a factorial design with the following elements: high or low top, upper vamp stabilizer, hollow midsole at midfoot level and lace anchors. 3 test subjects, students of Physical Education, took part. They performed 36 jumps each, in series of 3, with a recovering time of 3 s between jumps and 3 m between series. Each series was done wearing one of the 12 prototypes at random. Each jump was filmed at 150 Hz and then digitized. The angles of knee and ankle were calculated as a function of time. For the statistical analysis an analysis of variance (ANOVA) was made, considering as factors the elements introduced in the footwear and a level of significance of 0,05 was chosen. RESULTS: The results indicate the high top footwear limited the range of movement during ankle flexion-extension and they produce higher values of inversion than low top. With an upper vamp stabilizer, higher values of inversion were obtained than without it. On the other hand, with a hollow midsole, inversion values were lower. Introducing a movement control system in the rearfoot, by means of lace anchors, did not show influence on the studied movements. CONCLUSIONS: In this way, after landing on an irregular surface, the high top as well as an upper vamp stabilizer increase the degree of inversion, probably because these elements rigidify vertically the footwear and increase the adherence to the floor or to the irregular surface on which the subject IS. However, it must be considered that epidemiological studies state that high top footwear diminish the risk of acute ankle injuries in basketball players. The upper vamp stabilizer, on the contrary, only rigidifies vertically the footwear and it dos not offer any extra reinforcement of the joint, increasing the risk of suffering ankle injuries. REFERENCES: Stacoff, A.; Kalin, X.; Stiitsi, E. (1 989) Torsional movements of the foot during landing. Abstracs of the XI1 Congress of the International Society of Biomechanics. Los Angeles, 1085. Sussman, D. H.; Hamill, J.; Miller, M. (1988) Effect of shoe height and prophylactic taping on ankle joint motion during s~mulated basketball rebounding. In De Groot, G., Hollander, A.P.; Huijing, P.A.; Van lngen Schenau, G.J. (Eds.) Biomechanics XI-6

INFLUENCE OF THE FOOTBALL BOOT DESIGN ON SHOCK ABSORPTION

INTRODUCTION: A number of studies about the importance of sports shoe design on injuries prevention have been published in late years (Masson, 1989;Stacoff, 1988). Epidemiological studies indicate that football has special relevance with relation to suffering injuries (Hoff,1986; Ydes, 1990). During the practice of football a number of movement patterns such as jumping or running are performed(Reilly, 1976), being shock absorption a basic criterion for the design of footwear in Worts where such movement patterns occur. To improve the shock absorption of footwear two strategies are often adopted: to potentiate the natural mechanisms by means Of a better the tissue heel Or to increase the shock absorption capability of the footwear appropriately selecting the materials of the sole and insole. The aim the study was to evaluate the effect which different boot designs and different sole and insole materials had on load transMission during running. Based on a preliminary study, 3 boot prototypes and 4 insole prototypes were made. 8healthy football players were selected and they performed 6 runs with each of the 12possible combinations of boot/insole. The runs were performed in a football field and a speed of 4 m/s was determined controlled by electric photocells. The sequence of each condition was randomized for each subject. The subjects were instrumented with 2 accelerometers, attached to their skin by means of a strong bandage on tibia and forehead. The signals from the accelerometers were connected to a telemetry equipment which allowed the subject freer movements. With parameters obtained, an analysis of variance (ANOVA) was made. The level of significance chosen was of alfa < 0.05. To analyze the differences between conditions, an LSD test was made. RESULTS: One of the viscoelastic materials inserted in the insole offered a mean reduction of impacts of about 6%.One of' the materials of the boot sole showed a better capability of shock absorption, about 7%. The boots to which a special compartment for the heel pad did not improve shock absorption. Acceleration measured at tibia was of 6.01+0.06 times gravity (g) and at head it was of 2.45+2g.CONCLUSION: According to the results, an appropriate selection of insole and boot materials an improvement of shock absorption of 13% can be obtained. Although the tests were made on a natural grass football field and the speed of run was not too high, the values found for both tibia and forehead were high: this fact confirms the hypothesis that shock absorption is a basic criterion in the design of football boots from the point of view of protection from injuries. REFERENCES: Hoff, G.L and Martin, T.A.(1986). Outdoor and Indoor soccer: Injuries among youth players. Am. J. Sp. Med. 8,231-233.Masson, M. and Hess, H. (1989) Typicalsoccer injuries. Their effects on the design of the athletic shoe. In 6. Segesser & W.Pforringer (Eds.) The shoe in sport.London: Wolfe Publishing, Lld., 89-95.Reilly, T. (1 976) A motion analysis of work rate in differential roles in professional football match play. J. Human Mov. Stud.2, 87-97.Stacoff, A,; Denoth, J.; Kaelin, X. and Stuessi, E. (1988) Running injuries and shoe construction: Some possible relantionships. lnt. J. Sports Biomech. 4,342-357.Yde, J. and Nielsen, A.B. (1990) Sport injuries in adolescents' ball games: soccer,handball and basketball. Br. J. Sp. Med24(1), 51-54.8

Secadero tendalero con chimenea solar

El secado solar de frutas y hortalizas está siendo utilizado en distintos lugares del mundo y particularmente en Argentina. Si bien existen numerosos diseños de distinta complejidad, se presentan algunos problemas que requieren atención y estudio, especialmente en lo que se refiere a la tecnología de secaderos en convección natural. En el presente trabajo se detallan los aspectos constructivos de un tendalero adaptado para funcionar como secadero solar pasivo con una chimenea solar incorporada. El sistema básicamente consiste de un colector solar, cámara de secado y chimenea. Para el modelo de simulación se utilizó el SIMUSOL. Se analiza el sistema térmicamente y los resultados del ajuste de la simulación. Se muestran los resultados de los ensayos realizados: secado de pimiento para pimentón y membrillos. La simulación permitió determinar el flujo másico de aire dentro del secadero y resultó ser una herramienta útil a la hora del diseño. Los productos obtenidos son de buena calidad y el tiempo de secado se considera razonable para este tipo de secadero.Solar drying of fruits and vegetables is being used worldwide and particularly in Argentina. Although there are numerous designs of different complexity, they present some problems that require attention and study, especially when natural convection driers are used. This paper describes building aspects of a “tendalero” adapted for working as a passive solar drier with an incorporated solar chimney. The system essentially consists of a solar collector, a drying unit and a chimney. The simulation model used was SIMUSOL. A thermal analysis of the system is done and the results of adjustment simulation are considered. The results of the assays carried out, pepper for paprika and quince, are also shown. The simulation allowed to determine the mass flow rate of air inside the drier, and proved to be an important tool for design. The quality of dried products is good and the drying time is considered reasonable for this type of driers.Fil: Iriarte, Adolfo Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Agrarias; ArgentinaFil: Bistoni, S.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Agrarias; ArgentinaFil: Luque, V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Agrarias; ArgentinaFil: Lara, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Agrarias; ArgentinaFil: Brizuela, L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Agrarias; Argentin