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With the changing regulations in poultry processing, increased pressure is placed on integrators to reduce the number of human enteropathogenic bacteria on the final carcass and/or parts. Reducing the total number of bacteria on broiler carcasses before entering the evisceration side of the processing plant is projected to reduce the number of bacteria on the carcasses after chilling. This study was designed to evaluate the efficacy of a prototype wash cabinet using low volume, fluidic nozzles in combination with high pressure (450 psi) and hot water (60 °C) to remove bacteria from pre-scald, post-scald, or post picked carcasses. Carcasses (n = 5) from each location were obtained from a commercial processing plant, placed into individual sterile sample bags, placed into an insulated container, and transported to the U.S. National Poultry Research Center Pilot Plant within 30 min of collection. Carcasses were hung in standard shackles and sampled pre-wash with pre-moistened, cellulose swabs. All carcasses were washed in the prototype wash cabinet with 60 °C water at 450 psi at a line speed of 52 birds/minute on 15.24 cm centered shackles. Post-wash breast sponge samples were collected identical to pre-wash swabs. Buffered peptone water (BPW) was added, sponges stomached and serially diluted before plating onto total aerobic count (TAC), Enterobacteriaceae (ENT) and Escherichia. coli (EC) Petrifilm® cards. All PetriFilm® cards were incubated at 37 °C for 24 ± 2 h. After incubation, bacterial counts were recorded and converted to log10 CFU/swab. Samples were processed for Campylobacter species using the Tempo® CAM protocol. Four replications were conducted on separate dates. Paired t-tests were used to compare numbers recovered from breast swabs collected before and after the wash cabinet, significance reported at p < 0.05. Pre-scald samples had significant reductions of 2.50, 2.01, and 1.73 log10 colony-forming units/carcass (CFU/carcass) for TAC, Ent, and EC Petrifilm®, respectively, and a 2.21 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-scald, there were significant reductions of 2.09, 1.23, and 0.90 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 1.14 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-pick, significant reductions of 0.73, 1.53, and 0.99 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 0.86 CFU/carcass reduction of Campylobacter species using Tempo® CAM were reported. These data indicate that hot water at high pressure can reduce total bacterial load on carcasses and reduce pathogenic bacteria on carcasses prior to evisceration.

The purpose of this article is to provide a brief overview of the history of projection in education, discuss potential benefits to using projection technology, and finally share ideas for the use of projection throughout typical lesson content (e.g., introductory, skill, fitness and game activities) for Physical Education programs. This is also done to promote new perceptions regarding an educational technology that otherwise might be perceived as not applicable in Physical Education contexts; and share the potential positive outcomes from use.

The Johnsons Landing landslide occurred on 12 July 2012 on the shores of Kootenay Lake, British Columbia. The landslide consisted of poorly sorted, low-plasticity debris that initially descended a steep channel, before avulsing onto a glaciofluvial terrace. This event destroyed three homes and killed four people who lived on this terrace. This paper presents a back-analysis of this event using numerical runout modelling. It is shown that undrained flow can explain the observed channel avulsion with fewer model parameters than needed by previous analyses. This mechanism should be considered in similar settings, as ignoring it can lead to underestimation of runup and overtopping of natural and anthropogenic flow obstacles, such as landslide protection structures. Key words: landslide risk analysis, landslide runout modelling, Johnsons Landing landslide. Le glissement de terrain de Johnsons Landing s'est produit le 12 juillet 2012 sur les rives du lac Kootenay, en Colombie-Britannique. Le glissement de terrain consistait en des debris mal tries et de faible plasticite, qui avaient d'abord descendu un canal escarpe avant de s'evanouir sur une terrasse glaciofluviale. Cet evenement a detruit trois maisons et tue quatre personnes qui vivaient sur cette terrasse. Cet article presente une analyse en arriere de cet evenement a l'aide de la modelisation numerique de l'execution. Il est montre qu'un ecoulement non draine peut expliquer l'avulsion de canal observee avec moins de parametres de modele que ceux requis par les analyses precedentes. Ce mecanisme devrait etre envisage dans des contextes similaires, car son ignorance peut conduire a une sous-estimation de l'accumulation et du depassement d'obstacles naturels et anthropiques, tels que les structures de protection contre les glissements de terrain. [Traduit par la Redaction] Mots-cles: analyse du risque de glissement de terrain, modelisation du glissement de terrain, glissement de terrain de Johnsons Landing., 1. Introduction On 12 July 2012, an extremely rapid flow of soil, rock, and timber swept down Gar Creek, located on the shores of Kootenay Lake, British Columbia (Fig. 1). [...]

The forced vortex equation, based on the cross-stream inclination of a flow surface as it passes through a bend, is a common approach to estimating debris flow velocities. Here, we present the preliminary results of a study of superelevation and the correction factor k, used to adapt the forced vortex equation to debris flows, based on data from the Illgraben torrent in Switzerland. The definition of the radius of curvature, a factor in the calculation of superelevation velocities, is not found to exercise a large influence on the calculated velocities when using high resolution aerial images, with the choice of cross-section location and k-factor exercising a more significant influence. The k-factors found here fall within the range previously reported in the literature, ranging from approximately 1 to 7, and a previously suggested non-linear relationship with Froude numbers is evident in the dataset. Following the debris flow season of 2022, the study will be continued with additional debris flow events and the investigative methods will be extended to include high-resolution LiDAR sensors installed along the Illgraben torrent.

More detailed field measurements are required for a better understanding of surging debris flows. In this work, we analyze a debris flow at the field-scale using timelapse point clouds from a high-resolution, high-frequency 3D LiDAR sensor, which has been installed over a check dam on the fan of the Illgraben catchment in Switzerland. In our investigations, we manually measured the front velocity and tracked individual features such as large boulders and woody debris over a 25 m long channel segment. We observed a change in the front velocity as well as a difference in the velocity of large boulders and woody debris (vboulder ≈ 0.6 vwood) during the second surge of the event. We also estimated the discharge for different closely spaced channel sections based on automated measurements of the cross-sectional area and the surface velocity, which enabled us to infer spatial variations in the bed geometry and the velocity profile. From the discharge estimates, we then derived the volume of this event. Over the course of the next year, the amount of field-scale LiDAR data from the Illgraben will increase substantially and allow for an even more detailed analysis of fundamental debris-flow processes.

In-situ measurements of debris-flow properties are crucial for understanding their movement mechanisms and quantifying their impact. Here we present the first results of a field monitoring campaign, at Illgraben, Switzerland, to measure debris-flow parameters using high temporal (10 Hz) and spatial resolution LiDAR sensors at several locations along the channel. The point cloud data is projected onto video images to enhance visualization and aid in the interpretation of the measurements. We process the data using machine vision and deep learning based algorithms, and show that this system can accurately measure front and flow surface velocity, flow depth and bed elevation change, as well as the size, style of motion (e.g. rotating or floating without rotation) and trajectories of individual particles. This system thus provides a promising new method for inferring the internal dynamics of debris flows.

The volume of a debris flow is a critical parameter in hazard analysis, yet accurate estimates of volume are often unavailable due to mixing with larger rivers at the downstream end of alluvial fans. We describe a method to calculate the volume of debris flows using flow depth data collected at a check dam, using a Manning friction relation to describe the velocity of the debris flow as a function of flow depth, and the geometry of the channel cross section. The method is evaluated using a published data set from the USGS debris-flow flume where event volume and stage information have been accurately measured, and results in volume estimates either somewhat smaller than or up to 50% larger than observed volumes. We further demonstrate the method to single-surge and a multiple-surge debris flows observed at Illgraben.

Accurate debris-flow modelling depends on the ability to simulate surging and pulsing behaviour. However, our understanding of these phenomena is starved of observational constraints. Here we propose the use of seismic measurements, which resolve the arrival of coarse-grained roll wave fronts in debris flows at Illgraben, Switzerland. Roll waves likely play a key role in flow pulses but are typically only observed with point measurements like depth gauges. We compare in-torrent force plate measurements with near-torrent seismic records and discuss how these data can test existing roll wave theories.

Proglacial settings in the Alps are typically polygenetic, often characterized by a complex and discontinuous interplay between glacial, fluvial, and gravitational processes. These processes yield high volume of sediments, which usually exceeds the transportation capacity. The excessive proglacial sediment load leads to accumulation on slopes, and thus, to subsequent failures such as debris flows. Such failures can occur unexpectedly and harm the villages and infrastructure in the vicinity of proglacial environments. The northern slopes of the Ferret and Veny valleys in the Mont Blanc Massif are home to several polygenetic cones and are a stunning field laboratory for the exploration of the interplay between the glacial, fluvial, and gravitational processes. This study investigates one of the active and well-preserved polygenetic cones in these valleys, namely the Frébouge cone, to disentangle the geomorphic processes that contributed to its formation, and to reconstruct its evolution. To achieve these goals, detailed field, and remote mapping, 10Be surface exposure dating of different geomorphic features, and runout modelling with DAN3D® were applied. The geomorphological map revealed complex interactions of glacial, fluvial, debris flow, and rock and snow avalanche processes. The established chronology indicates two major fluxes of debris flows, the first one at ca. 2 ka, and the second at ca. 1 ka. In addition, a rock mass with a maximum volume of to 12 Mm3 collapsed in the upper reaches of the cone at 1.3 ± 0.1 ka and overran the cone, travelling more than 100 m up onto the opposite valley slope. Afterwards, the Frébouge Glacier overrode the cone several times leaving moraines and till, reaching its maximum extent ca. 300 years ago. This study underscores the untwisting of the complex interaction of surface processes in the Alpine valleys, which are prone to hit the urban areas and infrastructure. [ABSTRACT FROM AUTHOR]

The pre-historic rock avalanche at Avalanche Lake was a spectacularly mobile rock avalanche that resulted in the largest documented runup of any landslide on earth. The runout of the 200 [Mm.sup.3] event was a complex and three-dimensional process that created three distinct depositional lobes. There is some controversy as to whether the presence of glacial ice played an important role in the dynamics of this event. To investigate this hypothesis an advanced, three-dimensional numerical landslide runout model was used to reconstruct the dynamics of this event. It was found that a conventional runout model is able to reproduce the bulk characteristics of this event, including its spectacular runup, without accounting for glacial ice. A sensitivity analysis was performed to determine the factors that control the mobility of this event. It was found that low strength in the source zone, as well as the presence of significant internal strength, is required to reproduce the 600 m runup. This has important implications for the hazard analysis of rock avalanches. It appears as though large-volume rock avalanches can move with a friction angle lower than that expected for dry fragmented rock, and the runout process can be strongly influenced by internal strength. These important factors must be accounted for when performing forward analyses of this type of natural disaster. Key words: Avalanche Lake, numerical runout modeling, landslide dynamics, rock avalanche, Dan3D. L'avalanche de roches mobiles qui s'est produite durant la prehistoire sur le site d'Avalanche Lake est un phenomene spectaculaire qui a genere le plus grand eboulement du un glissement de terrain documente sur terre. Ce deplacement d'une masse de 200 [Mm.sup.3] de roches a ete un processus complexe et tridimensionnel, qui a entraine la formation de trois lobes de depot distincts. Il existe une certaine controverse quant au fait que la presence de glace a joue un role dans la dynamique de cette avalanche. Afin d'etudier cette hypothese, on a utilise un modele numerique tridimensionnel elabore de deplacement de glissement de terrain pour reconstituer la dynamique de l'avalanche. On a constate qu'un modele de deplacement classique permettait de reproduire les caracteristiques globales de l'avalanche, y compris l'eboulement qui l'accompagnait, sans tenir compte de la glace de glacier. On a effectue une analyse de sensibilite afin de determiner les facteurs qui influent sur la mobilite de l'avalanche. On a constate qu'une faible resistance dans la zone de depart de l'avalanche ainsi que la presence d'une resistance interne elevee etaient necessaires pour que l'on puisse reproduire l'eboulement, qui a parcouru une distance de 600 m. Cela a d'importantes repercussions sur l'analyse des risques d'avalanches rocheuses. Il semblerait que des avalanches comprenant des volumes importants de roches peuvent de deplacer avec un angle de frottement plus faible que l'angle prevu dans le cas de roches seches fragmentees et que le mecanisme d'avalanche puisse dependre fortement de la resistance interne. Ces facteurs importants doivent etre pris en compte lorsqu'on realise des analyses prospectives de ce type de catastrophe naturelle. [Traduit par la Redaction] Mots-cles : Avalanche Lake, modelisation numerique du deplacement d'une avalanche, dynamique de glissement de terrain, avalanche rocheuse, DAN3D., Introduction Quantitative risk analysis of rapid flow-like landslides requires estimates of vulnerability parameters (e.g., velocity) and the extent of the spatial impact zone (Fell et al. 2005). Empirical correlations routinely [...]