The strong and the hungry: Bias in capture methods for mountain hares (Lepus timidus).

Estimating density, age and sex structure of wild populations is a key objective in wildlife management. Live trapping is frequently used to collect data on populations of small and medium-sized mammals. Ideally, sampling mammal populations by live capturing of individuals provides a random and representative sample of the target population. Trapping data may, however, be biased. We used live-capture data from mountain hares Lepus timidus in Scotland to assess sampling bias between two different capture methods.Wecaptured hares using baited cage traps and long nets on five study areas in the Scottish Highlands. After controlling for the effects of body size, individuals caught in traps were lighter than individuals caught using long nets, suggesting that the body condition of hares differed between the capture methods. This tendency may reflect an increased risk-taking of individuals in poorer body condition and less aversion to entering traps in order to benefit from eating bait. Overall, we caught more adult hares than juveniles and more female hares than males. Our results show that estimates of density and population structure of mountain hares using livecapture data could be affected by the capture method used. We suggest that live-capture studies employ more than one capture method and test for heterogeneity in capture probability to minimise potential bias and achieve reliable estimates of population parameters

Holistic engineering design : a combined synchronous and asynchronous approach

To aid the creation and through-life support of large, complex engineering products, organizations are placing a greater emphasis on constructing complete and accurate records of design activities. Current documentary approaches are not sufficient to capture activities and decisions in their entirety and can lead to organizations revisiting and in some cases reworking design decisions in order to understand previous design episodes. Design activities are undertaken in a variety of modes; many of which are dichotomous, and thus each require separate documentary mechanisms to capture information in an efficient manner. It is possible to identify the modes of learning and transaction to describe whether an activity is aimed at increasing a level of understanding or whether it involves manipulating information to achieve a tangible task. The dichotomy of interest in this paper is that of synchronous and asynchronous working, where engineers may work alternately as part of a group or as individuals and where different forms of record are necessary to adequately capture the processes and rationale employed in each mode. This paper introduces complimentary approaches to achieving richer representations of design activities performed synchronously and asynchronously, and through the undertaking of a design based case study, highlights the benefit of each approach. The resulting records serve to provide a more complete depiction of activities undertaken, and provide positive direction for future co-development of the approaches

A New Bot Fly Species (Diptera: Oestridae) From Central Texas

The bot fly Cephenemyia albina (Diptera: Oestridae) is described from a relict pine forest in east-central Texas. This species presumably lives as a parasitic larva in the throat of white-tailed deer as do its two close relatives previously reported from both Texas and the Great Lakes region (C. phobifera (Clark) and C. jellisoni Townsend). Only the adult male is currently known

A joint motion & disparity motion estimation technique for 3D integral video compression using evolutionary strategy

3D imaging techniques have the potential to establish a future mass-market in the fields of entertainment and communications. Integral imaging, which can capture true 3D color images with only one camera, has been seen as the right technology to offer stress-free viewing to audiences of more than one person. Just like any digital video, 3D video sequences must also be compressed in order to make it suitable for consumer domain applications. However, ordinary compression techniques found in state-of-the-art video coding standards such as H.264, MPEG-4 and MPEG-2 are not capable of producing enough compression while preserving the 3D clues. Fortunately, a huge amount of redundancies can be found in an integral video sequence in terms of motion and disparity. This paper discusses a novel approach to use both motion and disparity information to compress 3D integral video sequences. We propose to decompose the integral video sequence down to viewpoint video sequences and jointly exploit motion and disparity redundancies to maximize the compression. We further propose an optimization technique based on evolutionary strategies to minimize the computational complexity of the joint motion disparity estimation. Experimental results demonstrate that Joint Motion and Disparity Estimation can achieve over 1 dB objective quality gain over normal motion estimation. Once combined with Evolutionary strategy, this can achieve up to 94% computational cost saving

Demo: Linux Goes Apple Picking: Cross-Platform Ad hoc Communication with Apple Wireless Direct Link

Apple Wireless Direct Link (AWDL) is a proprietary and undocumented wireless ad hoc protocol that Apple introduced around 2014 and which is the base for applications such as AirDrop and AirPlay. We have reverse engineered the protocol and explain its frame format and operation in our MobiCom '18 paper "One Billion Apples' Secret Sauce: Recipe of the Apple Wireless Direct Link Ad hoc Protocol." AWDL builds on the IEEE 802.11 standard and implements election, synchronization, and channel hopping mechanisms on top of it. Furthermore, AWDL features an IPv6-based data path which enables direct communication. To validate our own work, we implement a working prototype of AWDL on Linux-based systems. Our implementation is written in C, runs in userspace, and makes use of Linux's Netlink API for interactions with the system's networking stack and the pcap library for frame injection and reception. In our demonstrator, we show how our Linux system synchronizes to an existing AWDL cluster or takes over the master role itself. Furthermore, it can receive data frames from and send them to a MacBook or iPhone via AWDL. We demonstrate the data exchange via ICMPv6 echo request and replies as well as sending and receiving data over a TCP connection.Comment: The 24th Annual International Conference on Mobile Computing and Networking (MobiCom '18

Mountain Goat Removal in Olympic National Park: A Case Study of the Role of Organizational Culture in Individual Risk Decisions and Behavior

Using a case study, the authors explore the mediating role of organizational culture in individual Risk-taking decisions and behaviors. They argue that organizational culture can establish unique conditions that lead to highly reliable performance of high-Risk, undesired tasks. The authors also discuss the need for further research and its implications for Risk management

Age structure, dispersion and diet of a population of stoats (Mustela erminea) in southern Fiordland during the decline phase of the beechmast cycle

The dispersion, age structure and diet of stoats (Mustela erminea) in beech forest in the Borland and Grebe Valleys, Fiordland National Park, were examined during December and January 2000/01, 20 months after a heavy seed-fall in 1999. Thirty trap stations were set along a 38-km transect through almost continuous beech forest, at least 1 km apart. Mice were very scarce (nights, C/100TN) along two standard index lines placed at either end of the transect, compared with November 1999 (>60/100TN), but mice were detected (from footprints in stoat tunnels) along an 8 km central section of the transect (stations 14-22). Live trapping with one trap per station (total 317.5 trap nights) in December 2000 caught 2 female and 23 male stoats, of which 10 (including both females) were radio collared. The minimum range lengths of the two females along the transect represented by the trap line were 2.2 and 6.0 km; those of eight radio-tracked males averaged 2.9 ± 1.7 km. Stations 14-22 tended to be visited more often, by more marked individual stoats, than the other 21 stations. Fenn trapping at the same 30 sites, but with multiple traps per station (1333.5 trap nights), in late January 2001 collected carcasses of 35 males and 28 females (including 12 of the marked live-trapped ones). Another two marked males were recovered dead. The stoat population showed no sign of chronic nutritional stress (average fat reserve index = 2.8 on a scale of 1-4 where 4 = highest fat content); and only one of 63 guts analysed was empty. Nevertheless, all 76 stoats handled were adults with 1-3 cementum annuli in their teeth, showing that reproduction had failed that season. Prey categories recorded in descending frequency of occurrence were birds, carabid beetle (ground beetle), weta, possum, rat, and mouse. The frequencies of occurrence of mice and birds in the diet of these stoats (10% and 48%, respectively) were quite different from those in stoats collected in Pig Creek, a tributary of the Borland River (87%, 5%), 12 months previously when mice were still abundant. Five of the six stoat guts containing mice were collected within 1 km of stations 14-22

The vicious circle and infection intensity: The case of Trypanosoma microti in field vole populations

Objective: In natural populations, infection and condition may act synergistically to trigger a vicious circle: poor condition predisposes to host infections, which further reduce condition, and so on. If this vicious circle originates from a reduced resistance to infection, it will not only result in greater proneness to becoming infected of those that are in poorer condition, but it may also cause infections of higher intensity. Here, we investigate the temporal relationship between host condition and intensity of infection by a specific pathogen using as a system the dynamics of the protozoan Trypanosoma microti in field vole (Microtus agrestis) populations. Methods and results: With two years of longitudinal data from three monthly-sampled populations, we evaluated if individuals acquiring a high intensity of infection previously had lower haematological indicators of condition (red blood cells [RBCs] and lymphocyte counts) than those that acquired lower infection intensities. Also, the association of these indicators with past and present trypanosome blood levels was investigated. The individuals that developed high levels of parasitaemia were those that previously had low lymphocyte counts. Greater intensity of infection corresponded with lower RBCs only in low to moderate weight females, and no effect of intensity of infection on lymphocyte counts was observed. However, delayed effects of high trypanosome intensity were seen on both RBCs and lymphocytes. Conclusions: The vicious circle may also result in high infection intensity: individuals in poor condition are not only more likely to become infected by one pathogen; they may also be the most important source of infection for that and for other pathogens, and thus key protagonists for parasite dynamics.Fil: Beldomenico, Pablo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Telfer, Sandra. University of Liverpool; Reino UnidoFil: Gebert, Stephanie. University of Liverpool; Reino UnidoFil: Lukomski, Lukasz. University of Liverpool; Reino UnidoFil: Bennett, Malcolm. University of Liverpool; Reino UnidoFil: Begon, Michael. University of Liverpool; Reino Unid