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Microscopy techniques have been widely applied to observe cellular ultrastructure. Most of these techniques, such as transmission electron microscopy, produce high‐resolution images, but they may require extensive preparation, hampering their application for in vivo examination. Other approaches, such as fluorescent and fluorogenic probes, can be applied not only to fixed specimens but also to living cells when the probes are nontoxic. Fluorescence‐based methods, which are generally relatively easy to use, allow visual and (semi)quantitative studies of the ultrastructural organization and processes of the cell under natural as well as manipulated conditions. To date, there are relatively few published studies on the nearly ubiquitous marine protistan group Foraminifera that have used fluorescent and fluorogenic probes, despite their huge potential. The aim of the present contribution is to document the feasible application of a wide array of these probes to foraminiferal biology. More specifically, we applied fluorescence‐based probes to study esterase activity, cell viability, calcium signaling, pH variation, reactive oxygen species, neutral and polar lipids, lipid droplets, cytoskeleton structures, Golgi complex, acidic vesicles, nuclei, and mitochondria in selected foraminiferal species.

Microscopy techniques have been widely applied to observe cellular ultrastructure. Most of these techniques, such as transmission electron microscopy, produce high‐resolution images, but they may require extensive preparation, hampering their application for in vivo examination. Other approaches, such as fluorescent and fluorogenic probes, can be applied not only to fixed specimens but also to living cells when the probes are nontoxic. Fluorescence‐based methods, which are generally relatively easy to use, allow visual and (semi)quantitative studies of the ultrastructural organization and processes of the cell under natural as well as manipulated conditions. To date, there are relatively few published studies on the nearly ubiquitous marine protistan group Foraminifera that have used fluorescent and fluorogenic probes, despite their huge potential. The aim of the present contribution is to document the feasible application of a wide array of these probes to foraminiferal biology. More specifically, we applied fluorescence‐based probes to study esterase activity, cell viability, calcium signaling, pH variation, reactive oxygen species, neutral and polar lipids, lipid droplets, cytoskeleton structures, Golgi complex, acidic vesicles, nuclei, and mitochondria in selected foraminiferal species.

Fragility curves evaluating a risk of railway embankment fill and track ballast scour were developed. To develop fragility curves, two well-documented events of singletrack railway washout during floods in Japan were investigated. Type of damage to the railway was categorized into no damage, ballast scour, and embankment scour, in order of damage severity. Railway overtopping water depth for each event was estimated based on well-documented hydrologic and hydraulic analyses. Normal and log-normal fragility curves were developed based on damage probability derived from field records and the estimated overtopping water depth. A combined ballast and embankment scour model was validated by comparing the results of previous studies and the spatial distribution of railway damage type records., Hydraulic Structures and Flood Risk

Fragility curves evaluating a risk of railway embankment fill and track ballast scour were developed. To develop fragility curves, two well-documented events of singletrack railway washout during floods in Japan were investigated. Type of damage to the railway was categorized into no damage, ballast scour, and embankment scour, in order of damage severity. Railway overtopping water depth for each event was estimated based on well-documented hydrologic and hydraulic analyses. Normal and log-normal fragility curves were developed based on damage probability derived from field records and the estimated overtopping water depth. A combined ballast and embankment scour model was validated by comparing the results of previous studies and the spatial distribution of railway damage type records., Hydraulic Structures and Flood Risk

In this paper, the results of a benchmark test launched within the framework of the NSF-PIRE project Modelling of Flood Hazards and Geomorphic Impacts of Levee Breach and Dam Failure are presented. Experiments of two-dimensional dam-break flows over a sand bed were conducted at Université catholique de Louvain, Belgium. The water level evolution at eight gauging points was measured as well as the final bed topography. Intense scour occurred close to the failed dam, while significant deposition was observed further downstream. From these experiments, a benchmark was proposed to the scientific community, consisting of blind test simulations, that is, without any prior knowledge of the measurements. Twelve different teams of modellers from eight countries participated in the study. Here, the numerical models used in this test are briefly presented. The results are commented upon, in view of evaluating the modelling capabilities and identifying the challenges that may open pathways for further research. © 2012 Copyright International Association for Hydro-Environment Engineering and Research.

In this paper, the results of a benchmark test launched within the framework of the NSF-PIRE project Modelling of Flood Hazards and Geomorphic Impacts of Levee Breach and Dam Failure are presented. Experiments of two-dimensional dam-break flows over a sand bed were conducted at Université catholique de Louvain, Belgium. The water level evolution at eight gauging points was measured as well as the final bed topography. Intense scour occurred close to the failed dam, while significant deposition was observed further downstream. From these experiments, a benchmark was proposed to the scientific community, consisting of blind test simulations, that is, without any prior knowledge of the measurements. Twelve different teams of modellers from eight countries participated in the study. Here, the numerical models used in this test are briefly presented. The results are commented upon, in view of evaluating the modelling capabilities and identifying the challenges that may open pathways for further research. © 2012 Copyright International Association for Hydro-Environment Engineering and Research.

This paper examines the feasibility of applying a mobile, large scale particle image velocimetry (LS-PIV) system to a 300 m reach of a small river in order to estimate the discharge. Detailed velocity measurements at a number of locations were carried out using an acoustic Doppler current profiler (ADCP) and acoustic Doppler velocimetry (ADV) for inbank, bankfull and overbank flows. The lateral distributions of the velocity index k (i.e., the ratio of the depth-averaged velocity to the surface velocity) were found to be influenced by the secondary currents, channel vegetation and flow conditions. An attempt is made to quantify the relationship between secondary flow and the velocity index. Appropriate conclusions and advice relating to the practical use of a LS-PIV system as applied to a small river are given.

This paper examines the feasibility of applying a mobile, large scale particle image velocimetry (LS-PIV) system to a 300 m reach of a small river in order to estimate the discharge. Detailed velocity measurements at a number of locations were carried out using an acoustic Doppler current profiler (ADCP) and acoustic Doppler velocimetry (ADV) for inbank, bankfull and overbank flows. The lateral distributions of the velocity index k (i.e., the ratio of the depth-averaged velocity to the surface velocity) were found to be influenced by the secondary currents, channel vegetation and flow conditions. An attempt is made to quantify the relationship between secondary flow and the velocity index. Appropriate conclusions and advice relating to the practical use of a LS-PIV system as applied to a small river are given.