Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey

Predator–prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s-1 and accelerated up to 7.5 m s-2 with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5–8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival.

Ergodic Capacity of Cognitive TAS/GSC Relaying in Nakagami-m Fading Channels

We examine the impact of transmit antenna selection with receive generalized selection combining (TAS/GSC) for cognitive decode-and-forward (DF) relaying in Nakagami-m fading channels. We select a single transmit antenna at the secondary transmitter which maximizes the receive signal-to-noise ratio (SNR) and combine a subset of receive antennas with the largest SNRs at the secondary receiver. In an effort to assess the performance, we first derive the probability density function and cumulative distribution function of the end-to-end SNR using the moment generating function. We then derive new exact closed-form expression for the ergodic capacity. More importantly, by deriving the asymptotic expression for the high SNR approximation of the ergodic capacity, we gather deep insights into the high SNR slope and the power offset. Our results show that the high SNR slope is 1/2 under the proportional interference power constraint. Under the fixed interference power constraint, the high SNR slope is zero.

Assessing parenting capacity in child protection: towards a knowledge-based model

The assessment of parenting capacity continues to engender public concern in cases of suspected harm to children. This paper outlines a model for approaching this task based on the application of three key domains of knowledge in social work relating to facts, theory and practice wisdom. The McMaster Model of Family Assessment is identified out of this process and reworked to give it a sharper focus on parenting roles and responsibilities. Seven formative dimensions of parenting are then elicited and combined with an analytical process of identifying strengths, concerns, prospects for growth and impact on child outcomes. The resulting assessment framework, it is argued, adds rigour to professional judgements about parenting capacity and enhances formulations on risk in child protection.

Comfort Care Rounds: A Staff Capacity-Building Initiative in Long-Term Care Homes

This article reports a pilot evaluation of Comfort Care Rounds (CCRs)-a strategy for addressing long-term care home staff's palliative and end-of-life care educational and support needs. Using a qualitative descriptive design, semistructured individual and focus group interviews were conducted to understand staff members' perspectives and feedback on the implementation and application of CCRs. Study participants identified that effective advertising, interest, and assigning staff to attend CCRs facilitated their participation. The key barriers to their attendance included difficulty in balancing heavy workloads and scheduling logistics. Interprofessional team member representation was sought but was not consistent. Study participants recognized the benefits of attending; however, they provided feedback on how the scheduling, content, and focus could be improved. Overall, study participants found CCRs to be beneficial to their palliative and end-of-life care knowledge, practice, and confidence. However, they identified barriers and recommendations, which warrant ongoing evaluation.

Variance-Constrained Capacity of the Molecular Timing Channel with Synchronization Error

Molecular communication is set to play an important role in the design of complex biological and chemical systems. An important class of molecular communication systems is based on the timing channel, where information is encoded in the delay of the transmitted molecule - a synchronous approach. At present, a widely used modeling assumption is the perfect synchronization between the transmitter and the receiver. Unfortunately, this assumption is unlikely to hold in most practical molecular systems. To remedy this, we introduce a clock into the model - leading to the molecular timing channel with synchronization error. To quantify the behavior of this new system, we derive upper and lower bounds on the variance-constrained capacity, which we view as the step between the mean-delay and the peak-delay constrained capacity. By numerically evaluating our bounds, we obtain a key practical insight: the drift velocity of the clock links does not need to be significantly larger than the drift velocity of the information link, in order to achieve the variance-constrained capacity with perfect synchronization.

On the MIMO Capacity with Residual Transceiver Hardware Impairments

Radio-frequency (RF) impairments in the transceiver hardware of communication systems (e.g., phase noise (PN), high power amplifier (HPA) nonlinearities, or in-phase/quadrature-phase (I/Q) imbalance) can severely degrade the performance of traditional multiple-input multiple-output (MIMO) systems. Although calibration algorithms can partially compensate these impairments, the remaining distortion still has substantial impact. Despite this, most prior works have not analyzed this type of distortion. In this paper, we investigate the impact of residual transceiver hardware impairments on the MIMO system performance. In particular, we consider a transceiver impairment model, which has been experimentally validated, and derive analytical ergodic capacity expressions for both exact and high signal-to-noise ratios (SNRs). We demonstrate that the capacity saturates in the high-SNR regime, thereby creating a finite capacity ceiling. We also present a linear approximation for the ergodic capacity in the low-SNR regime, and show that impairments have only a second-order impact on the capacity. Furthermore, we analyze the effect of transceiver impairments on large-scale MIMO systems; interestingly, we prove that if one increases the number of antennas at one side only, the capacity behaves similar to the finite-dimensional case. On the contrary, if the number of antennas on both sides increases with a fixed ratio, the capacity ceiling vanishes; thus, impairments cause only a bounded offset in the capacity compared to the ideal transceiver hardware case.

Building capacity in palliative care for personal support workers in long-term care through experiential learning

Background

Providing palliative care in long-term care (LTC) homes is an area of growing importance. As a result, attention is being given to exploring effective palliative care learning strategies for personal support workers (PSWs) who provide the most hands-on care to LTC residents.

The purpose of this intervention was to explore hospice visits as an experiential learning strategy to increase the capacity of PSWs in palliative care, specifically related to their new learning, and how they anticipated this experience changed their practices in LTC.

This study utilised a qualitative descriptive design.

Eleven PSWs from four Ontario LTC homes were sent to their local hospice to shadow staff for one to two days. After the visit, PSWs completed a questionnaire with open-ended questions based on critical reflection. Data were analysed using thematic content analysis.

PSWs commented on the extent of resident-focused care at the hospice and how palliative care interventions were tailored to meet the needs of residents. PSWs were surprised with the lack of routine at the hospice but felt that hospice staff prioritised their time effectively in order to meet family and client care needs. Some PSWs were pleased to see how well integrated the PSW role is on the community hospice team without any hierarchical relationships. Finally, PSWs felt that other LTC staff would benefit from palliative care education and becoming more comfortable with talking about death and dying with other staff, residents and family members.

This study highlighted the benefits of PSWs attending a hospice as an experiential learning strategy. Future work is needed to evaluate this strategy using more rigorous designs as a way to build capacity within PSWs to provide optimal palliative care for LTC residents and their family members.

PSWs need to be recognised as important members within the interdisciplinary team. PSWs who shadow staff at hospices view this experience as a positive strategy to meet their learning needs related to palliative care.

Assessing Climate Effects on Railway Earthworks Using MASW

Many parts of the UK’s rail network were constructed in the mid-19th century long before the advent of modern construction standards. Historic levels of low investment, poor maintenance strategies and the deleterious effects of climate change have resulted in critical elements of the rail network being at significant risk of failure. The majority of failures which have occurred over recent years have been triggered by extreme weather events. Advance assessment and remediation of earthworks is, however, significantly less costly than dealing with failures reactively. It is therefore crucial that appropriate approaches for assessment of the stability of earthworks are developed, so that repair work can be better targeted and failures avoided wherever possible. This extended abstract briefly discusses some preliminary results from an ongoing geophysical research project being carried out in order to study the impact of climate or seasonal weather variations on the stability of a century old railway embankment on the Gloucestershire Warwickshire steam railway line in Southern England.