We present direct observations and monitoring data of a hyperconcentrated flow that occurred along La Lumbre ravine, one of the most active channels of Volcán de Colima in Mexico. Flow properties were inferred from video images and seismic data recorded by a geophone installed outside the channel. We collected flow samples 400 m upstream from the monitoring station and analyzed the variation of sediment concentration and grain-size distribution over time. A joint analysis of hydrological (i.e. flow velocity, wetted perimeter) and rheological (i.e. yield stress τ y and dynamic viscosity μ m ) parameters was performed to characterize the flow. Different flow regimes and sediment transport processes were identified and analyzed in comparison with both the amplitude and spectral features of the seismic signal. We observed differing sediment concentrations at the same discharge, suggesting a decoupling between sediment transport processes and discharge for low-magnitude flows. A straightforward correlation was found between the amplitude of the seismic signal and the sediment concentration, and a value of 1.8 × 10 À3 mm/s was identified that can be used as a threshold to recognize the hyperconcentrated phase of the flow. This information was tested on the complete seismic dataset gathered at La Lumbre ravine during the 2015 rainy season. We identified the transition from streamflow to hyperconcentrated flow (and/or vice versa) in 16 low-magnitude events and we validated this result using the video recordings. The correlation between seismic amplitude and sediment concentration is valid at La Lumbre ravine but would need to be tested in other locations for the development of automatic flow classification methods. This work contributes to standardized seismic methods for characterizing flow processes in volcanic environments, also for the development of lahar early warning systems. Copyright

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The Taenia crassiceps recombinant antigen KETc7 has been shown to be effective as a vaccine against experimental murine cysticercosis, a laboratory model used to test potentially promising molecules against porcine Taenia soliumcysticercosis. Based on the deduced amino acid sequence of this proline-rich polypeptide, three fragments, GK-1, GK-2, and GK-3, were chemically synthesized in linear form. Of the three peptides, only GK-1 induced sterile protection against T. crassicepscysticercosis in 40 to 70% of BALB/cAnN male mice. GK-1 is an 18-amino-acid peptide which contains at least one B-cell epitope, as demonstrated by its ability to induce an antibody response to the peptide and T. crassiceps antigen without need of a carrier protein. Immunofluorescence studies revealed that anti-GK1 antibodies strongly react with the native protein in the tegument ofT. crassiceps and also with anatomical structures ofT. solium eggs, oncospheres, cysticercus, and tapeworm. GK-1 also contains at least one T-cell epitope, capable of stimulating the proliferation of CD8+ and to a lower extent CD4+ T cells primed either with the free peptide orT. crassiceps total antigen. The supernatant of the stimulated cells contained high levels of gamma interferon and low levels of interleukin-4. Similar results were obtained with T cells tested for intracellular cytokine production, an indication of the peptide’s capacity to induce an inflammatory response. The remarkable protection induced by GK-1 immunization, its physicochemical properties, and its presence in all developmental stages ofT. solium point to this synthetic peptide as a strong candidate in the construction of a synthetic vaccine againstT. solium pig cysticercosis.

Abstract. One of the most common phenomena at Volcán de Colima is the annual development of lahars that runs mainly through the southern ravines of the edifice. Since 2011 the study and the monitoring of these flows and of the associated rainfall has been achieved by means of an instrumented station located along the Montegrande ravine, together with the systematic surveying of cross-topographic profiles of the main channel. From these, we present the comparison of the morphological changes experimented by this ravine during the 2013, 2014 and 2015 rainy seasons. The erosion/deposition effects of 11 lahars that occurred during this period of time were quantified by means of the topographic profiles taken at the beginning and at the end of the rainy seasons and before and after the major lahar event of 11 June 2013. We identified (i) an erosive zone between 2100 and 1950 m a.s.l., 8 • in slope, with an annual erosional rate of 10.3 % mainly due to the narrowness of the channel and to its high slope angle and (ii) an erosive-depositional zone, between 1900 and 1700 m a.s.l., (∼ 8 % erosion and ∼ 16 % deposition), characterized by a wider channel that decreases in slope angle (4 • ). Based on these observations, the major factors controlling the erosion/deposition rates in the Montegrande ravine are the morphology of the gully (i.e., channel bed slope and the cross section width) and the joint effect of sediment availability and accumulated rainfall. On the distal reach of the ravine, the erosion/deposition processes tend to be promoted preferentially one over the other, mostly depending on the width of the active channel. Only for extraordinary rainfall events are the largest lahars mostly erosive all along the ravine up to the distal fan where the deposition takes place. In addition, as well as the morphological characteristics of the ravine, the flow depth is a critical factor in controlling erosion, as deeper flows will promote erosion against deposition. Finally, by comparing rainfalls associated with lahars that originated after the last main eruptive episode that occurred in 2004-2005, we observed that higher accumulated rainfall was needed to trigger lahars in the 2013 and 2014 seasons, which points to a progressive stabilization of the volcano slope during a post-eruptive period. These results can be used as a tool to foresee the channel response to future volcanic activity, to improve the input parameters for lahar modeling and to better constrain the hazard zonation at Volcán de Colima.