Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management

Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems

Impact of massive neutrinos on the Higgs self-coupling and electroweak vacuum stability

The presence of right-handed neutrinos in the type I seesaw mechanism may lead to significant corrections to the RG evolution of the Higgs self-coupling. Compared to the Standard Model case, the Higgs mass window can become narrower, and the cutoff scale become lower. Naively, these effects decrease with decreasing right-handed neutrino mass. However, we point out that the unknown Dirac Yukawa matrix may impact the vacuum stability constraints even in the low scale seesaw case not far away from the electroweak scale, hence much below the canonical seesaw scale of 10^15 GeV. This includes situations in which production of right-handed neutrinos at colliders is possible. We illustrate this within a particular parametrization of the Dirac Yukawas and with explicit low scale seesaw models. We also note the effect of massive neutrinos on the top quark Yukawa coupling, whose high energy value can be increased with respect to the Standard Model case.Comment: 17 pages, 7 figures, minor revisions, version to appear in JHE

Natural images from the birthplace of the human eye

Here we introduce a database of calibrated natural images publicly available through an easy-to-use web interface. Using a Nikon D70 digital SLR camera, we acquired about 5000 six-megapixel images of Okavango Delta of Botswana, a tropical savanna habitat similar to where the human eye is thought to have evolved. Some sequences of images were captured unsystematically while following a baboon troop, while others were designed to vary a single parameter such as aperture, object distance, time of day or position on the horizon. Images are available in the raw RGB format and in grayscale. Images are also available in units relevant to the physiology of human cone photoreceptors, where pixel values represent the expected number of photoisomerizations per second for cones sensitive to long (L), medium (M) and short (S) wavelengths. This database is distributed under a Creative Commons Attribution-Noncommercial Unported license to facilitate research in computer vision, psychophysics of perception, and visual neuroscience.Comment: Submitted to PLoS ON

Proof of Concept: Wearable Augmented Reality Video See-Through Display for Neuro-Endoscopy

In mini-invasive surgery and in endoscopic procedures, the surgeon operates without a direct visualization of the patient’s anatomy. In image-guided surgery, solutions based on wearable augmented reality (AR) represent the most promising ones. The authors describe the characteristics that an ideal Head Mounted Display (HMD) must have to guarantee safety and accuracy in AR-guided neurosurgical interventions and design the ideal virtual content for guiding crucial task in neuro endoscopic surgery. The selected sequence of AR content to obtain an effective guidance during surgery is tested in a Microsoft Hololens based app

Reinforcement learning or active inference?

This paper questions the need for reinforcement learning or control theory when optimising behaviour. We show that it is fairly simple to teach an agent complicated and adaptive behaviours using a free-energy formulation of perception. In this formulation, agents adjust their internal states and sampling of the environment to minimize their free-energy. Such agents learn causal structure in the environment and sample it in an adaptive and self-supervised fashion. This results in behavioural policies that reproduce those optimised by reinforcement learning and dynamic programming. Critically, we do not need to invoke the notion of reward, value or utility. We illustrate these points by solving a benchmark problem in dynamic programming; namely the mountain-car problem, using active perception or inference under the free-energy principle. The ensuing proof-of-concept may be important because the free-energy formulation furnishes a unified account of both action and perception and may speak to a reappraisal of the role of dopamine in the brain

Perceived needs and satisfaction with care in people with multiple sclerosis: A two-year prospective study

<p>Abstract</p> <p>Background</p> <p>Considering the costs of multiple sclerosis (MS), it is crucial that the health-related services supplied are in accordance with needs as they are perceived by people with MS (PwMS). Satisfaction with care is related to quality of care and can provide health care providers with the means for improvement. The aim was to explore the perceived needs and satisfaction with care amongst PwMS over a two-year period, also taking sex and disease severity into consideration.</p> <p>Methods</p> <p>The sample consisted of 219 outpatients at a MS specialist clinic. Data on perceived needs and satisfaction with care were collected every six months using a questionnaire which included various dimensions of care. The data was analysed for the whole sample and on an individual level, as well as in subgroups with regard to sex and disease severity.</p> <p>Results</p> <p>There were no statistically significant variations in the proportion of PwMS with perceived needs concerning different health-related services during the study period. However, individual variations were found with regard to both perceived needs and satisfaction with care. Few PwMS perceived a continuous need for a specific service. However, the majority perceived a need for rehabilitation, assistive devices, transportation service for the disabled, psychosocial support/counselling and information on social insurance/vocational rehabilitation at least sometimes. Severe MS was associated with a greater perceived need for almost all the services studied and women experienced a need for psychosocial support/counselling to a greater extent than men. In relation to the different categories of health care staff, PwMS were most satisfied with nurses with regard to all dimensions of care. They were least satisfied with the availability of psychosocial support/counselling; and information about social insurance/vocational rehabilitation.</p> <p>Conclusion</p> <p>Despite the large proportion of individuals with mild disease severity in our sample, a considerable number of needs were identified of which many, on an individual level, varied over time. Key services demanded by PwMS were identified. Also the level of satisfaction with care varied and areas with a potential for improvement were identified such as the availability of rehabilitation services including an increase in the supply of psychosocial support and counselling.</p

Neutrophils in cancer: neutral no more

Neutrophils are indispensable antagonists of microbial infection and facilitators of wound healing. In the cancer setting, a newfound appreciation for neutrophils has come into view. The traditionally held belief that neutrophils are inert bystanders is being challenged by the recent literature. Emerging evidence indicates that tumours manipulate neutrophils, sometimes early in their differentiation process, to create diverse phenotypic and functional polarization states able to alter tumour behaviour. In this Review, we discuss the involvement of neutrophils in cancer initiation and progression, and their potential as clinical biomarkers and therapeutic targets

Fast polarization mechanisms in the uniaxial tungsten-bronze relaxor strontium barium niobate SBN-81

The high-frequency dielectric response of the uniaxial strontium barium niobate crystals with 81% of Sr has been studied from 1 kHz to 30 THz along the polar c axis by means of several techniques (far infrared, time domain terahertz, high-frequency and low-frequency dielectric spectroscopies) in a wide temperature interval 20–600 K. Relaxor properties were observed in the complex dielectric response and four main excitations were ascertained below the phonon frequencies. These fast polarization mechanisms take place at THz, GHz and MHz ranges and show different temperature evolution. The central mode excitation in the THz range, related to anharmonic dynamics of cations, slightly softens from high temperatures and then hardens below T ~ 400 K. Below the phase transition (at T ~ 330 K) an additional microwave excitation appears near 10 GHz related to micro domain wall oscillations. The strongest relaxation appears in the GHz range and slows down on cooling according to the Arrhenius law. Finally, another relaxation, present in the MHz range at high temperatures, also slows down on cooling at least to the kHz range. These two relaxations are due to polar fluctuations and nanodomains dynamics. Altogether, the four excitations explain the dielectric permittivity maximum in the kHz range