Long-Tailed Pygmy Rice Rats Modify Their Behavioural Response and Faecal Corticosterone Metabolites in Response to Culpeo Fox but Not to Lesser Grison

Even though behavioural and physiological reactions to predation risk exhibited by prey species have received considerable attention in scientific journals, there are still many questions still unsolved. Our aim was to broaden the knowledge on one specific question: do long-tailed pygmy rice rats adapt their behavioural and physiological antipredator strategies depending on the predator species? For this question, we live-trapped in a temperate forest in Southern Chile long-tailed pygmy rice rats (Oligoryzomys longicaudatus), which were exposed to three predator odour phases (Phase 0: preliminary, no predator cues; Phase 1: one plot with culpeo fox faeces (Lycalopex culpaeus), one plot with lesser grison (Galictis cuja) faeces and one plot acting as a control with no odour; Phase 2: post treatment, no predator cues). We measured the behavioural response by the capture ratio. To assess the physiological stress response, we collected fresh faecal samples to quantify faecal corticosterone metabolites (FCM). Our results showed that O. longicaudatus increased both the capture ratio and FCM levels in the presence of culpeo cues. Culpeo foxes have higher densities in the study area than G. cuja and exhibit a higher activity pattern overlap with O. longicaudatus. Moreover, it has been also been reported in other regions that L. culpaeus consumption of O. longicaudatus is more frequent compared to G. cuja diet. The increase in capturability could be because traps can be regarded as a shelter in high-risk settings, but it can also be explained by the predator inspection behaviour. The increase in FCM concentrations during culpeo treatment can be linked to the adaptive mobilisation of energy to execute antipredator responses to increase survival chances.

Estimation of load capture ratio for evaluating LID facilities performance in Korea

Accurate performance evaluation is required for efficient design or installation of Low Impact Development (LID) facilities. However, the existing evaluation method in Korea needs to be improved since it has been derived for non-point reduction facilities. The purpose of this study is to propose a new design formula for three types of LID facilities. Through the long-term continuous simulation of EPA SWMM, the Load Capture Ratio (LCR) for LID facilities such as bio-retentions, infiltration trenches, and vegetative swales was estimated. As a result of the sensitivity analysis to verify the newly derived LCR formula, it can be seen that not only the regional rainfall characteristics but also the infiltration capacity of the native soil play an important role in the accuracy of the proposed LCR formula.

Leakiness and flow capture ratio of insect pectinate antennae

The assumption that insect pectinate antennae, which are multi-scale organs spanning over four orders of magnitude in size among their different elements, are efficient at capturing sexual pheromones is commonly made but rarely thoroughly tested. Leakiness, i.e. the proportion of air that flows within the antenna and not around it, is a key parameter which depends on both the macro- and the microstructure of the antenna as well as on the flow velocity. The effectiveness of a structure to capture flow and hence molecules is a trade-off between promoting large leakiness in order to have a large portion of the flow going through it and a large effective surface area to capture as much from the flow as possible, therefore leading to reduced leakiness. The aim of this work is to measure leakiness in 3D-printed structures representing the higher order structure of an antenna, i.e. the flagellum and the rami, with varying densities of rami and under different flow conditions. The male antennae of the moth Samia cynthia (Lepidoptera: Saturniidae) were used as templates. Particle image velocimetry in water and oil using 3D-printed scaled-up surrogates enabled us to measure leakiness over a wide range of equivalent air velocities, from 0.01 m s −1 to 5 m s −1 , corresponding to those experienced by the moth. We observed the presence of a separated vortex ring behind our surrogate structures at some velocities. Variations in the densities of rami enabled us to explore the role of the effective surface area, which we assume to permit equivalent changes in the number of sensilla that host the chemical sensors. Leakiness increased with flow velocity in a sigmoidal fashion and decreased with rami density. The flow capture ratio, i.e. the leakiness multiplied by the effective surface area divided by the total surface area, embodies the above trade-off. For each velocity, a specific structure leads to a maximum flow capture ratio. There is thus not a single pectinate architecture which is optimal at all flow velocities. By contrast, the natural design seems to be robustly functioning for the velocity range likely to be encountered in nature.

Study on multiple rainfall data applied to debris flow warning in Taiwan

<p>Due to climate change, precipitation characteristics have been significantly variation and rainfall patterns are presented more concentrated, high-intensity and long-duration trend in the past two decades. Catastrophic debris-flow disaster threaten lives and property of residents. For mitigation impact of debris-flow, SWCB (Soil and Water Conservation Bureau, Taiwan) has had a leading role in sponsoring debris-flow research and developing a rainfall-based debris-flow warning model. Early warning criteria for debris-flow triggered are also determined depending on the historical rainfall data, and the observational data of rain-gauge are adopted to issue debris-flow warning. However, application of rain-gauge rainfall data has some disadvantages such as low density in mountain area, observation failure to properly represent actual rainfall condition, and data transmission likely interrupted during heavy rainfall or Typhoon. In order to improve the efficiency of debris-flow warning system, two types of gridded precipitation are analyzed and discussed in this study, which are the spatial interpolation rainfall of rain-gauge and the radar-estimated rainfall (QPESUMS). For comparison the differents of multiple rainfall data mentioned above with rain-guage, the third quartile is firstly applied to calculate the regional representative rainfall from grid cells within warning issued area. The results show that the spatial interpolation rainfall underestimates the rainfall intensity and cumulative rainfall owing to the influence of complex topography. By contrast, the radar-estimated rainfall has the advantage in comprehension of the rainfall spatial variability and provide a more complete spatial coverage. Besides, for assessing the appropriate and feasibility of multiple rainfall data applied to debris flow warning, the disaster–capture ratio has been proposed which is defined as the number of debris-flow hazards after issuing warning divided by total number of debris- flow hazards. According to analyis results of historical disaster records from 2012 to 2016, the disaster–capture ratio are 47.6%, 38.1% and 61.9% as warning issued refer to rain gauge, the spatial interpolation rainfall and the radar-estimated rainfall respectively. By the aforementioned process, we realize that the application of radar-estimated rainfall to debris flow warning is obviously increasing efficiency of debris-flow warning ,and gives assistance for reducing uncertainty of rainfall observational data, especially in mountain area.</p>

Preacceleration of the multicharged ions with the different A/Z ratios in single RFQ channel

The preacceleration of multicharged ions with the different A/Z ratios extracted from electron cyclotron resonance (ECR) sources is discussed in this report. The capture ratio, emittances and current values of multicharged ions may be better if the ions are preaccelerated before their injection into a booster synchrotron. There is a considerable possibility of separate preacceleration of multicharged ions with different A/Z ratios in a single radio-frequency quadrupole (RFQ) channel. The magnitude of the injection energy into RFQ is about a few keV/u whereas the magnitudes of the injection energy into booster or following linac cascade are 300 keV/u. In addition in this paper we discuss the approach of the fast channel parameter optimization technique by using swarm computations and gradient descend for improving the capture ratio. The optimizations aimed at changing the regular part of the RFQ or matching section profile to improve the matching of the arbitrary oriented in phase space input beam.

The Impact of the Construction of Sponge Cities on the Surface Runoff in Watersheds, China

In order to study the effect of the construction of the sponge cites on the process of urban water circulation in China, we analyzed the precipitation data from 756 stations across China between 1961 and 2011 and national land-use data in 2014. The spatial distribution characteristics of built-up area and amount of annual average runoff interception in sponge cities were explored in five different zonal scale levels. Assuming that the sponge cities have been built at the national-level construction land and the volume capture ratio of annual runoff is taken as 85%, the amount of annual average runoff interception in sponge cities is 988.58 × 108 m3 during 1961 to 2011 in China, where the annual precipitation is greater than or equal to 400 mm. The cities with more amount of annual average runoff interception are mostly distributed in Beijing-Tianjin-Hebei region, the Yangtze River Delta, and the Pearl River Delta. As to the Haihe River Basin, the annual average amount of surface water resources is 135.69 × 108 m3 between 2005 and 2014, and the amount of annual average runoff interception is 219.58 × 108 m3 from 1961 to 2011. The construction of sponge cities has the greatest impact on the surface water resources in the Haihe River Basin. Taking 80%–85% as the volume capture ratio of annual runoff in sponge cities is not reasonable, which may lead to the irrational exploitation and utilization of regional water and soil resources.