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Introduction: More than a quarter of tumors are missed by magnetic resonance imaging/ultrasound (MRI/US) fusion-guided biopsy, the majority due to software-based misregistration. Transrectal approaches to biopsy are typically performed in the lateral decubitus position; conversely, diagnostic MRI is performed with the patient lying supine. Any position-related difference in prostate location or gland deformation could potentially exacerbate misregistration at subsequent biopsy. Methods: Fifteen healthy male volunteers (mean age 35.9 years, range 27–53) were included in this prospective, institutional review board-approved study. Each volunteer had an MRI performed in the supine position, followed by the second in the lateral decubitus position (mimicking a typical biopsy position). MRI images were co-registered and analyzed in order to assess prostate translocation and distortion. Results: Whole prostate translocation of ≥5 mm was observed in 20% of patients and ≥3 mm in 60% of patients. When dividing the prostate into prostatic sectors, the prostatic base demonstrated the largest positional difference. When plotting the translocation directions with relative volume difference, there was a moderate negative correlation trend in the latero-lateral direction. Only minimal distortion was observed, with similar distortion among all prostatic sectors. Conclusions: Positional change affects the prostate translocation, however, the effect on prostate distortion appears to be negligible. Prostate translocation in latero-lateral direction can be minimized with larger bladder volumes. Thereby, prostate translocation needs to be considered alongside software misregistration error; however, positional change should not affect software registration of MRI/US fusion-guided prostate biopsy.

Circulating tumor-derived DNA (ctDNA) can be used to monitor cancer dynamics noninvasively. Patients with small tumors have few copies of ctDNA in plasma, resulting in limited sensitivity to detect low-volume or residual disease. We show that sampling limitations can be overcome and sensitivity for ctDNA detection can be improved by massively parallel sequencing when hundreds to thousands of mutations are identified by tumor genotyping. We describe the INtegration of VAriant Reads (INVAR) analysis pipeline, which combines patient-specific mutation lists with both custom error-suppression methods and signal enrichment based on biological features of ctDNA. In this framework, the sensitivity can be estimated independently for each sample based on the number of informative reads, which is the product of the number of mutations analyzed and the average depth of unique sequencing reads. We applied INVAR to deep sequencing data generated by custom hybrid-capture panels, and showed that when ~106 informative reads were obtained INVAR allowed detection of tumor-derived DNA fractions to parts per million (ppm). In serial samples from patients with advanced melanoma on treatment, we detected ctDNA when imaging confirmed tumor volume of ~1cm3. In patients with resected early-stage melanoma, ctDNA was detected in 40% of patients who later relapsed, with higher rates of detection when more informative reads were obtained. We further demonstrated that INVAR can be generalized and allows improved detection of ctDNA from whole-exome and low-depth whole-genome sequencing data.

This study assessed the feasibility of using diffusion kurtosis imaging (DKI) as a measure of tissue heterogeneity and proliferation to predict the response of high grade serous ovarian cancer (HGSOC) to neoadjuvant chemotherapy (NACT). Seventeen patients with HGSOC were imaged at 3 T and had biopsy samples taken prior to any treatment. The patients were divided into two groups: responders and non-responders based on Response Evaluation Criteria In Solid Tumours (RECIST) criteria. The following imaging metrics were calculated: apparent diffusion coefficient (ADC), apparent diffusion (Dapp) and apparent kurtosis (Kapp). Tumour cellularity and proliferation were quantified using histology and Ki-67 immunohistochemistry. Mean Kapp before therapy was higher in responders compared to non-responders: 0.69 ± 0.13 versus 0.51 ± 0.11 respectively, P = 0.02. Tumour cellularity correlated positively with Kapp (rho = 0.50, P = 0.04) and negatively with both ADC (rho = −0.72, P = 0.001) and Dapp (rho = −0.80, P app (rho = 0.53, P = 0.03) but not with ADC or Dapp. In conclusion, Kapp was found to be a potential predictive biomarker of NACT response in HGSOC, which suggests that DKI is a promising clinical tool for use oncology and radiology that should be evaluated further in future larger studies.

PURPOSESpatial heterogeneity of tumours is a major challenge in precision oncology. The relationship between molecular and imaging heterogeneity is still poorly understood, as it relies on the accurate co-registration of medical images and tissue biopsies. tumour moulds can guide the localization of biopsies, but their creation is time consuming, technologically challenging, and difficult to interface with routine clinical practice. These hurdles have so far hindered the progress in the area of multiscale integration of tumour heterogeneity data.METHODSWe have developed an open source computational framework to automatically produce patient-specific 3D-printed moulds that can be used in the clinical setting. Our approach achieves accurate co-registration of sampling location between tissue and imaging, and integrates seamlessly with clinical, imaging and pathology workflows.RESULTSWe applied our framework to patients with renal cancer undergoing radical nephrectomy. We created personalised moulds for five patients, obtaining Dice similarity coefficients between imaging and tissue sections ranging from 0.86 to 0.93 for tumour regions, and between 0.70 and 0.76 for healthy kidney. The framework required minimal manual intervention, producing the final mould design in just minutes, while automatically taking into account clinical considerations such as a preference for specific cutting planes.CONCLUSIONOur work provides a robust and automated interface between imaging and tissue samples, enabling the development of clinical studies to probe tumour heterogeneity on multiple spatial scales.

Electroreception in marine fishes occurs across a variety of taxa and is best understood in the chondrichthyans (sharks, skates, rays, and chimaeras). Here, we present an up-to-date review of what is known about the biology of passive electroreception and we consider how electroreceptive fishes might respond to electric and magnetic stimuli in a changing marine environment. We briefly describe the history and discovery of electroreception in marine Chondrichthyes, the current understanding of the passive mode, the morphological adaptations of receptors across phylogeny and habitat, the physiological function of the peripheral and central nervous system components, and the behaviours mediated by electroreception. Additionally, whole genome sequencing, genetic screening and molecular studies promise to yield new insights into the evolution, distribution, and function of electroreceptors across different environments. This review complements that of electroreception in freshwater fishes in this special issue, which provides a comprehensive state of knowledge regarding the evolution of electroreception. We conclude that despite our improved understanding of passive electroreception, several outstanding gaps remain which limits our full comprehension of this sensory modality. Of particular concern is how electroreceptive fishes will respond and adapt to a marine environment that is being increasingly altered by anthropogenic electric and magnetic fields.

Non-consumptive effects of predators can have important impacts on aquatic food webs, but there are few data on how predators change the behaviour of Caribbean reef fishes. Such changes may include behavioural responses to the invasive predatory lionfish (Pterois volitans/P. miles). This study used an aquarium experiment to examine the behaviour of herbivorous parrotfish (Scarus iseri) in the absence of other fish (control), with a non-piscivore present, and with a predatory threat from a native grouper or lionfish. Treatments were repeated with and without additional parrotfish shelters to examine the potential effects of degraded reefs (loss of refuges). Using video, parrotfish behaviours (sheltering, swimming in open areas, foraging, aggressive conspecific interactions, bite rates, and shoaling behaviour) were recorded for groups of four parrotfish. Compared to the control, the average number of parrotfish hiding was reduced by 65 % and foraging shoals were 10 % larger when threatened by grouper, likely as a specific response to an ambush predator. When exposed to lionfish, parrotfish reduced their bite rates by 50 %, possibly to be more vigilant of this predator’s unique stalking behaviour. The absence of additional shelter had limited effects although parrotfish formed 10 % larger shoals when swimming in open water, potentially as a defensive behaviour because of a perceived lack of refuges. The reduction in parrotfish bite rates caused by lionfish may have important demographic consequences. Furthermore, parrotfishes are important grazers of macroalgae, and these behavioural changes may exacerbate the direct effects of lionfish predation and potentially affect reef benthic dynamics.

Hyperpolarized 13C Magnetic Resonance Imaging (13C-MRI) provides a highly sensitive tool to probe tissue metabolism in vivo and has recently been translated into clinical studies. We report the cerebral metabolism of intravenously injected hyperpolarized [1–13C]pyruvate in the brain of healthy human volunteers for the first time. Dynamic acquisition of 13C images demonstrated 13C-labeling of both lactate and bicarbonate, catalyzed by cytosolic lactate dehydrogenase and mitochondrial pyruvate dehydrogenase respectively. This demonstrates that both enzymes can be probed in vivo in the presence of an intact blood-brain barrier: the measured apparent exchange rate constant (kPL) for exchange of the hyperpolarized 13C label between [1–13C]pyruvate and the endogenous lactate pool was 0.012 ± 0.006 s−1 and the apparent rate constant (kPB) for the irreversible flux of [1–13C]pyruvate to [13C]bicarbonate was 0.002 ± 0.002 s−1. Imaging also revealed that [1–13C]pyruvate, [1–13C]lactate and [13C]bicarbonate were significantly higher in gray matter compared to white matter. Imaging normal brain metabolism with hyperpolarized [1–13C]pyruvate and subsequent quantification, have important implications for interpreting pathological cerebral metabolism in future studies., Graphical abstract Image 1

© The Ecological Society of America The removal of thousands of structures associated with oil and gas development from the world's oceans is well underway, yet the environmental impacts of this decommissioning practice remain unknown. Similar impacts will be associated with the eventual removal of offshore wind turbines. We conducted a global survey of environmental experts to guide best decommissioning practices in the North Sea, a region with a substantial removal burden. In contrast to current regulations, 94.7% of experts (36 out of 38) agreed that a more flexible case-by-case approach to decommissioning could benefit the North Sea environment. Partial removal options were considered to deliver better environmental outcomes than complete removal for platforms, but both approaches were equally supported for wind turbines. Key considerations identified for decommissioning were biodiversity enhancement, provision of reef habitat, and protection from bottom trawling, all of which are negatively affected by complete removal. We provide recommendations to guide the revision of offshore decommissioning policy, including a temporary suspension of obligatory removal.

Predator avoidance is fundamental for survival and it can be particularly challenging for prey animals if physical movement away from a predatory threat is restricted. Many sharks and rays begin life within an egg capsule that is attached to the sea bed. The vulnerability of this sedentary life stage is exacerbated in skates (Rajidae) as the compulsory ventilatory activity of embryos makes them conspicuous to potential predators. Embryos can reduce this risk by mediating ventilatory activity if they detect the presence of a predator using an acute electrosense. To determine how early in embryonic life predator elicited behavioral responses can occur, the reactions of three different age groups (1/3 developed, 2/3 developed, and near hatching) of embryonic thornback rays Raja clavata were tested using predator-type electric field stimuli. Egg capsules were exposed to continuous or intermittent stimuli in order to assess varying predator-type encounter scenarios on the ventilatory behavior of different developmental stages. All embryos reacted with a "freeze response" following initial electric field (E-field) exposure, ceasing ventilatory behavior in response to predator presence, demonstrating electroreceptive functionality for the first time at the earliest possible stage in ontogeny. This ability coincided with the onset of egg ventilatory behavior and may represent an effective means to enhance survival. A continuous application of stimuli over time revealed that embryos can adapt their behavior and resume normal activity, whereas when presented intermittently, the E-field resulted in a significant reduction in overall ventilatory activity across all ages. Recovery from stimuli was significantly quicker in older embryos, potentially indicative of the trade-off between avoiding predation and adequate respiration. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 721-729, 2016.

Carbonic anhydrase buffers tissue pH by catalyzing the rapid interconversion of carbon dioxide (CO2) and bicarbonate (HCO3−). We assessed the functional activity of CAIX in two colorectal tumor models, expressing different levels of the enzyme, by measuring the rate of exchange of hyperpolarized 13C label between bicarbonate (H13CO3−) and carbon dioxide (13CO2), following injection of hyperpolarized H13CO3−, using 13C-magnetic resonance spectroscopy (13C-MRS) magnetization transfer measurements. 31P-MRS measurements of the chemical shift of the pH probe, 3-aminopropylphosphonate, and 13C-MRS measurements of the H13CO3−/13CO2 peak intensity ratio showed that CAIX overexpression lowered extracellular pH in these tumors. However, the 13C measurements overestimated pH due to incomplete equilibration of the hyperpolarized 13C label between the H13CO3− and 13CO2 pools. Paradoxically, tumors overexpressing CAIX showed lower enzyme activity using magnetization transfer measurements, which can be explained by the more acidic extracellular pH in these tumors and the decreased activity of the enzyme at low pH. This explanation was confirmed by administration of bicarbonate in the drinking water, which elevated tumor extracellular pH and restored enzyme activity to control levels. These results suggest that CAIX expression is increased in hypoxia to compensate for the decrease in its activity produced by a low extracellular pH and supports the hypothesis that a major function of CAIX is to lower the extracellular pH. Cancer Res; 75(19); 4109–18. ©2015 AACR.

OBJECTIVE: To compare image quality, artefact, and distortion in standard echo-planar imaging (EPI) with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) for prostate magnetic resonance imaging (MRI) diffusion-weighted imaging (DWI) in patients with previous total hip replacement (THR). METHODS: 21 male subjects with a clinical suspicion for, or known prostate cancer and previous THR were scanned at 1.5 T using a phased-array body coil. DWI was obtained using single-shot EPI and PROPELLER techniques using fat saturation (PROPELLER-DWI-FS), and without (PROPELLER-DWI-NFS). Image quality (the overall impression of diagnostic quality) was compared to T2-weighted (T2WI) imaging using a 5-point Likert scale, with diffusion sequences additionally scored for artefact and distortion according to a 4-point scale, with artefact defined as the amount of prostate affected and distortion as the degree of warping of the organ. The T2W and DW image volumes were compared to produce quantitative distortion maps. A two-sample Wilcoxon test compared the qualitative scores, with inter-reader variability calculated using Cohen's kappa. RESULTS: 21 patients were included in the study, with an average age of 70.4 years and PSA 9.2 ng/ml. Hip metalwork was present bilaterally in 3 patients, left-sided in 9, and right-sided in 9. PROPELLER-DWI-FS significantly improved image quality (p < 0.01) and reduced distortion (p < 0.01) when compared to standard EP-DWI. Artefact was not shown to be significantly improved. The last 5 patients in the study were additionally imaged with PROPELLER-DWI-NFS, which resulted in a significant reduction in artefact compared to EP-DWI (p < 0.05). Quantitative distortion was significantly lower compared to EP-DWI for both PROPELLER with fat saturation (p < 0.01) and without fat saturation (p < 0.01). CONCLUSION: PROPELLER-DWI demonstrates better image quality and decreases both artefact and distortion compared to conventional echo planar sequences in patients with hip metalwork.

IntroductionAcquired brain injury (ABI) is a major cause of morbidity and mortality in childhood. Specialist rehabilitation services are often situated far from families and local services may be non-standardised and fragmented. A strategic level of understanding is needed to improve patient care and outcomes. Roadmapping techniques are commonly used in industry settings to discover and present a systematic understanding of structures; however, they are rarely used in the healthcare setting. With continuing pressures on healthcare systems worldwide, they provide an effective method for examining services.MethodsThe Institute for Manufacturing (IfM) strategic roadmapping method was used to identify areas of difficulty and opportunities in paediatric neurorehabilitation. Participants included stakeholders from a wide range of professions and sectors who have input with children after ABI.ResultsDelegates identified a range of ‘layers’ covering trends, drivers, current experience and unmet needs. From these layers, four priorities were identified and further expanded.These included: ‘access to medical and therapy expertise close(r) to home’, ‘shared understanding across family, school and health’, ‘family and professional awareness of resources and support’ and ‘establishing a centre for rehabilitation technology evaluation, advice and co-ordination of services and research’.ConclusionThe IfM strategic roadmapping method identified and developed key areas for development in the field of paediatric neurological rehabilitation. Healthcare professionals looking at strategic level difficulties should strongly consider the use of such systematic tools when evaluating areas of practice.

Proponents of marine renewable energy worldwide highlight that regulatory and consenting procedures are a significant barrier to the upscaling of infrastructure required to transform the energy generation sector. Uncertainties about the cumulative effects of marine renewable energy developments cause substantial delays during the consenting process, which are exacerbated by the lack of clarity about how to assess cumulative effects. These obstacles have contributed to perceptions that this essential emerging industry receives disproportionate scrutiny relative to established maritime activities. However, alongside legislated targets to reduce carbon emissions, there are legal obligations to protect, maintain and improve the condition of the marine environment. As the imperative to halt the decline in the condition of the environment increases, so expectations of cumulative impact assessments grow and the risk of consenting delays persists. To investigate how robust current cumulative impact assessment practise is, a novel evaluation framework was developed and applied to Environmental Statements of the world's largest offshore wind farms, currently in United Kingdom waters. The framework was designed to evaluate cumulative impact assessments relative to the information needs of decision-makers tasked with managing cumulative effects. We found that current practise does not meet those needs, that there is dissonance between science and practise, and problematic variability between assessments was observed. Straightforward recommendations for improved practise are provided, which if implemented may ease the perceived regulatory burden by clarifying practise. We also highlight additional steps that could enable project-led cumulative impact assessments to better support regional marine management. The results and recommendations will be of interest to countries worldwide where marine renewable energy is emerging alongside ecosystem-approach and marine spatial planning aspirations.

Objective To prospectively investigate the longitudinal effect of ejaculatory abstinence on MRI-measured seminal vesicle (SV) volume and whole-prostate ADC over consecutive days. Methods 15 healthy male volunteers (mean 35.9 years, range 27–53) underwent 3-T MRI at baseline and 1, 2 and 3 days post-ejaculation. Prostate and SV volumes were derived by volume segmentation and whole-gland apparent diffusion coefficient (ADC) values calculated. A mixed-effects linear regression compared ADC values and prostate/seminal vesicle volumes in each volunteer between studies in a pairwise manner. Results All subjects completed the four MRIs. Mean prostate volume was 22.45 cm3 (range 13.04–31.21 cm3), with no change between the four studies (p = 0.89–0.99). 13/15 subjects showed SV volume reduction from baseline to day 1, with group-mean decreasing from 6.45 to 4.80 cm3 (−25.6%, p

Introduction Deforestation significantly impacts large carnivores that depend on large tracts of interconnected forest habitat and that are sensitive to human activities. Understanding the relationship between habitat use and spatial distribution of such species across human modified landscapes is critical when planning effective conservation strategies. This study assessed the presence of potential landscape connectivity thresholds resulting from habitat fragmentation associated with different deforestation patterns using a scale-based approach that links species-specific home ranges with the extent of anthropogenic activities. The objectives were (1) to quantify the spatial and temporal distribution of natural vegetation for five common deforestation patterns and (2) to evaluate the connectivity associated with these patterns and the existence of potential thresholds affecting jaguar dispersal. The Bolivian lowlands, located within jaguar conservation units, were analysed with landscape metrics to capture the spatial and temporal changes within deforested areas and to determine potential impact on jaguar connectivity and connectivity thresholds for dispersal. Results Over the period of 1976–2005, the amount of natural vegetation has decreased by more than 40% in all locations with the biggest changes occurring between 1991 and 2000. Landscape spatial structure around jaguar locations showed that jaguars used areas with mean proportion of natural areas = 83.14% (SE = 3.72%), mean patch density = 1.16 patches/100 ha (SE = 0.28 patches/100 ha), mean patch area = 616.95 ha (SE = 172.89 ha) and mean edge density = 705.27 m/ha (SE = 182.19 m/ha).We observed strong fragmentation processes in all study locations, which has resulted in the connectivity of jaguar habitat decreasing to

Offshore Wind Turbine (OWT) support structures are invariably subject to colonisation by marine organisms, which are not spatially or temporally linear. Marine Growth (MG) varies based on location and season, and with structural and material characteristics. MG is a major consideration for engineers. As organisms settle on the structure they may increase surface roughness and cross-sectional area, altering drag and inertia coefficients and increasing hydrodynamic loading. Furthermore, the added mass from MG also influences structural integrity. As such, there is considerable uncertainty surrounding the response of OWTs to MG, as this phenomenon is often overlooked in FEA modelling. This paper uses the parametric FEA model of an OWT support structure developed in (Martinez-Luengo, Kolios, and Wang 2017) to analyse how different growth rates and patterns of zonation of MG affect the structural integrity of the system. MG has a great impact in the fatigue life of the structure, as a reduction of 58.6-59.2% is presented in the baseline scenarios.

Concurrent with the development of wind energy, research activity on wind energy generation and wildlife has evolved significantly during the last decade. This chapter presents an overview of remaining key knowledge gaps, consequent future research directions and their significance for management and planning for wind energy generation. The impacts of wind farms on wildlife are generally site-, species- and season-specific and related management strategies and practices may differ considerably between countries. These differences acknowledge the need to consider potential wildlife impacts for each wind farm project. Still, the ecological mechanisms guiding species’ responses and potential vulnerability to wind farms can be expected to be fundamental in nature. A more cohesive understanding of the causes, patterns, mechanisms, and consequences of animal movement decisions will thereby facilitate successful mitigation of impacts. This requires planning approaches that implement the mitigation hierarchy effectively to reduce risks to species of concern. At larger geographical scales, population-level and cumulative impacts of multiple wind farms (and other anthropogenic activity) need to be addressed. This requires longitudinal and multiple-site studies to identify species-specific traits that influence risk of mortality, notably from collision with wind turbines, disturbance or barrier effects. In addition, appropriate pre- and post-construction monitoring techniques must be utilized. Predictive modelling to forecast risk, while tackling spatio-temporal variability, can guide the mitigation of wildlife impacts at wind farms.

This study investigated the effect of temporal resolution on the dual-input pharmacokinetic (PK) modelling of dynamic contrast-enhanced MRI (DCE-MRI) data from normal volunteer livers and from patients with hepatocellular carcinoma. Eleven volunteers and five patients were examined at 3 T. Two sections, one optimized for the vascular input functions (VIF) and one for the tissue, were imaged within a single heart-beat (HB) using a saturation-recovery fast gradient echo sequence. The data was analysed using a dual-input single-compartment PK model. The VIFs and/or uptake curves were then temporally sub-sampled (at interval ▵t = [2-20] s) before being subject to the same PK analysis. Statistical comparisons of tumour and normal tissue PK parameter values using a 5% significance level gave rise to the same study results when temporally sub-sampling the VIFs to HB▵t4 s. However, sub-sampling to ▵t4 s did adversely affect the statistical comparisons. Temporal sub-sampling of just the liver/tumour tissue uptake curves at ▵t ≤ 20 s, whilst using high temporal resolution VIFs, did not substantially affect PK parameter statistical comparisons. In conclusion, there is no practical advantage to be gained from acquiring very high temporal resolution hepatic DCE-MRI data. Instead the high temporal resolution could be usefully traded for increased spatial resolution or SNR.

Assessing and managing the cumulative impacts of human activities on the environment remains a major challenge to sustainable development. This challenge is highlighted by the worldwide expansion of marine renewable energy developments (MREDs) in areas already subject to multiple activities and climate change. Cumulative effects assessments in theory provide decision makers with adequate information about how the environment will respond to the incremental effects of licensed activities and are a legal requirement in many nations. In practise, however, such assessments are beset by uncertainties resulting in substantial delays during the licensing process that reduce MRED investor confidence and limit progress towards meeting climate change targets. In light of these targets and ambitions to manage the marine environment sustainably, reducing the uncertainty surrounding MRED effects and cumulative effects assessment are timely and vital. This review investigates the origins and evolution of cumulative effects assessment to identify why the multitude of approaches and pertinent research have emerged, and discusses key considerations and challenges relevant to assessing the cumulative effects of MREDs and other activities on ecosystems. The review recommends a shift away from the current reliance on disparate environmental impact assessments and limited strategic environmental assessments, and a move towards establishing a common system of coordinated data and research relative to ecologically meaningful areas, focussed on the needs of decision makers tasked with protecting and conserving marine ecosystems and services.

The considerable extent of construction and operation of marine renewable energy developments (MRED) within U.K. and adjacent waters will lead, among other things, to the emission of electromagnetic fields (EMF) and subsea sounds into the marine environment. Migratory fishes that respond to natural environmental cues, such as the Earth's geomagnetic field or underwater sounds, move through the same waters that the MRED occupy, thereby raising the question of whether there are any effects of MRED on migratory fishes. Diadromous species, such as the Salmonidae and Anguillidae, which undertake large-scale migrations through coastal and offshore waters, are already significantly affected by other human activities leading to national and international conservation efforts to manage any existing threats and to minimize future concerns, including the potential effect of MRED. Here, the current state of knowledge with regard to the potential for diadromous fishes of U.K. conservation importance to be affected by MRED is reviewed. The information on which to base the review was found to be limited with respect to all aspects of these fishes' migratory behaviour and activity, especially with regards to MRED deployment, making it difficult to establish cause and effect relationships. The main findings, however, were that diadromous species can use the Earth's magnetic field for orientation and direction finding during migrations. Juveniles of anadromous brown trout (sea trout) Salmo trutta and close relatives of S. trutta respond to both the Earth's magnetic field and artificial magnetic fields. Current knowledge suggests that EMFs from subsea cables may interact with migrating Anguilla sp. (and possibly other diadromous fishes) if their movement routes take them over the cables, particularly in shallow water (

To investigate the ability of elasmobranchs to distinguish between differing prey-type electric fields we examined the electroreceptive foraging behaviour of a model species, Scyliorhinus canicula (small-spotted catshark). Catshark preferences were studied by behaviourally conditioning them to swim through narrow tunnels, and on exit presenting them simultaneously with two different electric fields. Their subsequent choices of the following paired options were recorded; (i) Two artificial electric fields (dipole electrodes) with different magnitude direct current (D.C.), (ii) Two artificial electric fields, one D.C. and the other alternating current (A.C.), of the same magnitude, and (iii) similar magnitude, natural and artificial D.C. electric fields associated with shore crabs and dipole electrodes respectively. We found a highly significant preference for the stronger D.C. electric field and a less pronounced, but still significant, preference for the A.C. electric field rather than the D.C. electric field. No preference was demonstrated between the artificial and natural D.C. electric fields. The findings are discussed in relation to the animal’s diet and ecology and with regard to anthropogenic sources of electric fields within their habitat.

Marine renewable energy promises to assist in the effort to reduce carbon emissions worldwide. As with any large-scale development in the marine environment, however, it comes with uncertainty about potential environmental impacts, most of which have not been adequately evaluated—in part because many of the devices have yet to be deployed and tested. We review the nature of environmental and, more specifically, ecological effects of the development of diverse types of marine renewable energy—covering marine wind, wave, tidal, ocean current, and thermal gradient—and discuss the current state of knowledge or uncertainty on how these effects may be manifested. Many of the projected effects are common with other types of development in the marine environment; for example, additional structures lead to concerns for entanglement, habitat change, and community change. Other effects are relatively unique to marine energy conversion, and specific to the type of energy being harnessed, the individual device type, or the reduction in energy in marine systems. While many potential impacts are unavoidable but measurable, we would argue it is possible (and necessary) to minimize others through careful device development and site selection; the scale of development, however, will lead to cumulative effects that we must understand to avoid environmental impacts. Renewable energy developers, regulators, scientists, engineers, and ocean stakeholders must work together to achieve the common dual objectives of clean renewable energy and a healthy marine environment.

To examine potential effects of male–female interactions on the sexes' foraging behaviour, we studied equal-sized, single- and mixed-sex groups of a benthic elasmobranch, the small-spotted catshark, in response to electric stimuli. A total of 88 size-matched, adult individuals were repeatedly presented with a range of artificial, prey type electric fields (E fields) under laboratory conditions in groups of (1) four males, (2) four females and (3) two of each sex. Females in single-sex groups were more responsive towards E fields than both single- and mixed-sex group males, despite showing similar activity levels. Equally, females in mixed-sex groups were more responsive than males in mixed groups, but showed similar activity levels. Furthermore, females in mixed-sex groups were less responsive to E fields than females from single-sex groups, despite showing similar activity levels. Males in mixed-sex groups were less responsive than males in single-sex groups, but were more active. These results indicate more intense foraging behaviour among females than males and significant reductions in foraging behaviour when grouped with the opposite sex. Both findings are probably associated with consequences of differing reproductive strategies and resultant sexual conflict (specifically male harassment and female avoidance).

A functional form for the vascular concentration of MRI contrast agent after intravenous bolus injection was developed that can be used to model the concentration at any vascular site at which contrast concentration can be measured. The form is based on previous models of blood circulation, and is consistent with previously measured data at long post-injection times, when the contrast agent is fully and evenly dispersed in the blood. It allows the first-pass and recirculation peaks of contrast agent to be modelled, and measurement of the absolute concentration of contrast agent at a single time point allows the whole time course to be rescaled to give absolute contrast agent concentration values. This measure of absolute concentration could be performed at a long post-injection time using either MRI or blood-sampling methods. In order to provide a model that is consistent with measured data, it was necessary to include both rapid and slow extravasation, together with excretion via the kidneys. The model was tested on T(1)-weighted data from the descending aorta and hepatic portal vein, and on T*(2)-weighted data from the cerebral arteries. Fitting of the model was successful for all datasets, but there was a considerable variation in fit parameters between subjects, which suggests that the formation of a meaningful population-averaged vascular concentration function is precluded.

the uk government's strategy for reducing greenhouse gas emissions to meet carbon mitigation obligations and the wider aims on sustainable development has provided the impetus for a rapid growth in activity associated with offshore renewable energy, particularly offshore wind farms. recently, consents for offshore renewable energy development (ored) were approved in three strategic areas—the outer thames estuary, the greater wash and the eastern irish sea. the scale of the planned developments means that each will have a large environmental footprint and multiple ored will have a cumulative effect on the environment. here we discuss current understanding of ored construction, operation and decommissioning with regard to the potential interaction with elasmobranchs because of the worrying status of elasmobranch populations within the uk coastal zone. based on the likely interactions between elasmobranchs and ored a framework is proposed which aims to promote cooperative initiatives between elasmobranch conservation management and the offshore renewables industry.

Summary 1Global-scale environmental degradation and its links with non-renewable fossil fuels have led to an increasing interest in generating electricity from renewable energy resources. Much of this interest centres on offshore renewable energy developments (ORED). The large scale of proposed ORED will add to the existing human pressures on coastal ecosystems, therefore any ecological costs and benefits must be determined. 2The current pressures on coastal ecology set the context within which the potential impacts (both positive and negative) of offshore renewable energy generation are discussed. 3The number of published peer-review articles relating to renewable energy has increased dramatically since 1991. Significantly, only a small proportion of these articles relate to environmental impacts and none considers coastal ecology. 4Actual or potential environmental impact can occur during construction, operation and/or decommissioning of ORED. 5Construction and decommissioning are likely to cause significant physical disturbance to the local environment. There are both short- and long-term implications for the local biological communities. The significance of any effects is likely to depend on the natural disturbance regime and the stability and resilience of the communities. 6During day-to-day operation, underwater noise, emission of electromagnetic fields and collision or avoidance with the energy structures represent further potential impacts on coastal species, particularly large predators. The wider ecological implications of any direct and indirect effects are discussed. 7Synthesis and applications. This review demonstrates that offshore renewable energy developments will have direct and, potentially, indirect consequences for coastal ecology, with these effects occurring at different scales. Ecologists should be involved throughout all the phases of an ORED to ensure that appropriate assessments of the interaction of single and multiple developments with the coastal environment are undertaken.

Over a number of decades the process of prey choice has been investigated using fishes as model predators. Using fishes for the model has allowed the proximate factors that determine how a mobile predator finds and chooses to eat the prey encountered within a variable 3-D environment to be estimated. During prey choice a number of constraints exist, in particular most fish predators will eat their prey whole thus their jaws and gut create functional limitations once a prey has been attacked. By considering the relationship between the size of the prey and the predator's feeding apparatus and feeding motivation this study explores the link between mechanistic studies and theoretical, optimal foraging based predictions. How the prediction of prey choices made by the fish following prey encounter can be reconciled with what is likely to he found in the fish's stomach is discussed. This study uses a progression of empirical examples to illustrate how the limits of functional constraints and prey choice at different stages of motivation to feed can be taken into account to improve predictions of predator prey choice.

Summary 1 Climate is changing. Predictions are for at least a 3 °C rise in mean temperature in northern Europe over the next century. Existing severe impacts of nutrients and inappropriate fish stocking in freshwater systems remain. 2 Effects of warming by 3 °C above ambient, nutrient addition and the presence or absence of sticklebacks Gasterosteus aculeatus were studied in experimental microcosms dominated by submerged plants, mimicking shallow lake ecosystems. 3 Warming had considerably smaller effects on the phytoplankton community than did fish and nutrients. It had very minor effects on chlorophyll a and total phytoplankton biovolume. However, it significantly decreased the biovolumes of Cryptophyceae (a major component in the controls) and Dinophyceae. Contrary to expectation, warming did not increase the abundance of blue-green algae (cyanophytes). Warming decreased the abundances of Cryptomonas erosa (Cryptophyceae) and Oocystis pusilla (Chlorophycota) and increased those of two other green algae, Tetraedron minimum and Micractinium pusillum. It had no effect on a further 17 species that were predominant in a community of about 90 species. 4 Fish and nutrients, either together or separately, generally increased the crops of most of the 21 abundant species and of the algal groups. Exceptions were for diatoms and chrysophytes, which were very minor components of the communities. Fish, but neither nutrients nor warming, increased the number of species of phytoplankton detected. This was probably through removal of zooplankton grazers, and parallels terrestrial studies where the presence of top predators, by controlling herbivores, leads to increased plant diversity. 5 There was no particular pattern in the taxonomy or biological characteristics of those species affected by the treatments. In particular, there was no link between organism size (a surrogate for many important biological features of phytoplankton species) and the effects of warming, nutrient addition or presence or absence of fish. However, all species were relatively small and potentially vulnerable to grazing. 6 Synthesis and applications. The results suggest that fears of an increasing abundance of cyanophytes with current projections of global warming may be unrealized, at least in shallow unstratified lakes still dominated by macrophytes. However, they emphasize that eutrophication and fish manipulations remain very important impact factors that determine the abundance of phytoplankton and subsequent problems caused by large growths.

To aid the extraction of the portal venous input function (PVIF) from axial dynamic contrast-enhanced CT images of the liver, eliminating the need for full manual outlining of the vessel across time points.A cohort of 20 patients undergoing perfusion CT imaging of the liver was examined. Dynamic images of the liver were reformatted into contiguous thin slices. A region of interest was defined within a transverse section of the portal vein on a single contrast-enhanced image. This region of interest was then computationally projected across all thin slices for all time points to yield a semi-automated PVIF curve. This was compared against the "gold-standard" PVIF curve obtained by conventional manual outlining.Bland-Altman plots of curve characteristics indicated no substantial difference between automated and manual PVIF curves [concordance correlation coefficient in the range (0.66, 0.98)]. No substantial differences were shown by Bland-Altman plots of derived pharmacokinetic parameters when a suitable kinetic model was applied in each case [concordance correlation coefficient in range (0.92, 0.95)].This semi-automated method of extracting the PVIF performed equivalently to a "gold-standard" manual method for assessing liver function. Advances in knowledge: This technique provides a quick, simple and effective solution to the problems incurred by respiration motion and partial volume factors in the determination of the PVIF in liver dynamic contrast-enhanced CT.

e21032 Background: Circulating tumour DNA (ctDNA) is released by cancer cells into the bloodstream and can be analysed via liquid biopsy, providing a real-time snapshot of tumour burden. After treatment, ctDNA concentrations may be low, making detection challenging, and collecting larger sample volumes may be impractical. Our study aims to achieve high-sensitivity monitoring of melanoma patients melanoma on therapy, maximising the number of mutations targeted per patient by individualised sequencing. Methods: 72 patients with stage 3 or 4 melanoma have so far been recruited to MelResist, a translational research study. 235 plasma, urine, tumour and buffy coat samples have been analysed for 10 BRAF mutant metastatic melanoma patients receiving systemic therapies, and 30 matched CT scans were analysed for RECIST response. Exome or targeted sequencing were carried out on tumour samples and plasma at baseline and progression and mutations identified were used to design individualised amplicon and hybrid-capture sequencing panels targeting hundreds to thousands of mutations per patient. Results: Baseline ctDNA allele fraction predicted for overall survival ( r = -0.56, p < 0.05). Longitudinal analysis of ctDNA showed that mutant allele fractions significantly correlated with tumour burden from CT imaging ( r = 0.79, p < 0.0001) and ctDNA changes were concordant with 20/22 (90%) of RECIST response events. ctDNA allele fractions increased with a lead time of 70 days relative to serum lactate dehydrogenase, a standard measure of disease burden (IQR = 42-142 days). Targeting multiple mutations per patient enabled detection of less than one mutant genome copy per sample and allowed comprehensive monitoring of clonal evolution on therapy, even using limited sample volumes. Conclusions: Analysis of an initial cohort of BRAF mutant metastatic melanoma patients has confirmed feasibility to apply an individualised targeted sequencing panel on both plasma and urine DNA. For a given sample volume, monitoring multiple mutations improves detection sensitivity compared to targeting individual loci, has predictive value and can be applied to all melanoma patients, irrespective of BRAF mutation status.

Top predators inhabiting a dynamic environment, such as coastal waters, should theoretically possess sufficient cognitive ability to allow successful foraging despite unpredictable sensory stimuli. The cognition-related hunting abilities of marine mammals have been widely demonstrated. Having been historically underestimated, teleost cognitive abilities have also now been significantly demonstrated. Conversely, the abilities of elasmobranchs have received little attention, despite many species possessing relatively large brains comparable to some mammals. The need to determine what, if any, cognitive ability these globally distributed, apex predators are endowed with has been highlighted recently by questions arising from environmental assessments, specifically whether they are able to learn to distinguish between anthropogenic electric fields and prey bioelectric fields. We therefore used electroreceptive foraging behaviour in a model species, Scyliorhinus canicula (small-spotted catshark), to determine cognitive ability by analysing whether elasmobranchs are able to learn to improve foraging efficiency and remember learned behavioural adaptations. Positive reinforcement, operant conditioning was used to study catshark foraging behaviour towards artificial, prey-type electric fields (Efields). Catsharks rewarded with food for responding to Efields throughout experimental weeks were compared with catsharks that were not rewarded for responding in order to assess behavioural adaptation via learning ability. Experiments were repeated after a 3-week interval with previously rewarded catsharks this time receiving no reward and vice versa to assess memory ability. Positive reinforcement markedly and rapidly altered catshark foraging behaviour. Rewarded catsharks exhibited significantly more interest in the electrical stimulus than unrewarded catsharks. Furthermore, they improved their foraging efficiency over time by learning to locate and bite the electrodes to gain food more quickly. In contrast, unrewarded catsharks showed some habituation, whereby their responses to the electrodes abated and eventually entirely ceased, though they generally showed no changes in most foraging parameters. Behavioural adaptations were not retained after the interval suggesting learned behaviour was not memorised beyond the interval. Sequences of individual catshark search paths clearly illustrated learning and habituation behavioural adaptation. This study demonstrated learning and habituation occurring after few foraging events and a memory window of between 12 h and 3 weeks. These cognitive abilities are discussed in relation to diet, habitat, ecology and anthropogenic Efield sources. © 2013 Springer-Verlag Berlin Heidelberg.

In the marine environment there are natural magnetic and electric fields associated with both physical and biological sources, and there are anthropogenic electromagnetic fields (EMFs) that permeate it. Many marine animals can detect electric and magnetic fields and utilize them in such important life processes as movement, orientation and foraging. Here, these EMFs are explored and discussed in terms of how they arise, their properties (particularly those that are measurable) and the animals that have the ability to detect them. Then the evidence base for whether anthropogenic EMFs can affect sensitive receptor animals is explored. As marine renewable energy developments (MREDs) expand rapidly worldwide, with multiple devices and networks of subsea cables that emit EMFs into the marine environment, it is necessary to focus on their interaction with marine animals. The MRED industry has to take EMFs into account, so the industry perspective is also covered. Finally, suggestions are made on how research on EMFs associated with MREDs (and other sources) and its interaction with marine animals should advance in future.

Following the construction of a large-scale public aquarium, we were presented with an opportunity to investigate how wild caught Caribbean reef fish respond to their first encounter with a novel environment. Within the constraints of this opportunity, we designed a behavioural study to determine the reef fishes' response to a new habitat in relation to their locomotory mode. Nine species of fish representing three locomotory modes: carangiform, sub-carangiform and labriform/sub-carangiform were observed over a four-week period following their first introduction to the aquarium. Fish activity levels and spatial distribution were quantified in relation to time since their first encounter with the novel environment. The most important result was that, regardless of locomotory mode or ecology, all of the species extensively explored the novel environment rather than settle on the first habitat that they encountered. This is a particularly interesting result for territorial species. More specifically, however, there were significant differences between species in activity through time. Carangiform activity level was lowest in the initial phases of an encounter with the novel environment subsequently rising to a stable level. The other species had variable activity throughout the study, but all of them exhibited a phase of low activity at some stage during the study. In terms of the fishes' use of the 2.5 million litres of water, six species utilised the whole of the aquarium based on a predefined zoning scheme. Although the initial activity level was low, carangiform swimmers used at least 90% of the zones in the early phases of an encounter with the novel environment and subsequently used all of the zones. Sub-carangiform species also used 100% of the zones by the end of the study. Three of the four labriform/sub-carangiform swimmers used a maximum of 90% of the zones. There was no significant difference between species in their use of the zones. However, each individual zone was subject to differential use by the fish. Owing to the extensive scale of the aquarium, we discuss the applicability of the behavioural results obtained to the natural environment in the context of the ecology of the species of fish studied.

When a three-spined stickleback Gasterosteus aculeatus encountered prey simultaneously the probability of hanging and the median pursuit time were greater than when prey were encountered sequentially. During simultaneous prey encounter fish did not choose to attack the more profitable prey but instead the nearer prey was handled first except when the difference between the two prey sizes was large. No difference was found in the level of total energetic intake by the fish regardless of prey size pairing. Fish that handled and ate the first prey of a pair in

The race for a timely combat of climate change through the reduction of greenhouse gasses such as carbon dioxide has pushed renewable energy developments to a higher echelon. At present, wind is one of the most profitable sources of exploitable renewable energy. Wind farms are popping up at many places worldwide. Their expansion on land, however is constrained, because sites where wind farms do not conflict with the high-quality environmental standards of the local community are limited. Being uninhabited, the marine environment offers a vast area for wind farm development. Being uninhabited, however, does not equal not being subject to impact. The sea and oceans host rich ecosystems, many of which have and continue to deliver priceless and indispensable goods and services to mankind. Offshore wind farm development is hence subject to environmental impact assessment and residual impacts should be carefully monitored. Most, if not all, current offshore wind farms are accompanied by an environmental monitoring programme. These programmes should be considered the ‘finger on the pulse’ to avoid surpassing critical impact levels. They further ensure the achievement of the knowledge base needed to adjust new developments in a scientifically and environmentally sensitive and sound manner. On 26–28 November 2013, the Royal Belgian Institute of Natural Sciences organised the international scientific WinMon.BE 2013 conference on ‘‘Environmental impacts of offshorewind farms: learning from the past to optimise future monitoring programmes’’ (http:// odnature.naturalsciences.be/winmonbe2013).During the Guest editors: Steven Degraer, Jennifer Dannheim, Andrew B. Gill, Han Lindeboom & Dan Wilhelmsson / Environmental impacts of offshore wind farms

A basic ecological tenet is that a predator chooses the prey that it consumes according tothe energetic gain available in relation to the time cost of dealing with each prey. For afish predator, the energetic content of prey increases with size whilst there is an associatedincrease in handling time (Werner, 1974; Kislalioglu & Gibson, 1976; Hoyle & Keast,1986; Gill & Hart, 1994). Prey choice can be based on the profitability of each size ofprey where the greatest profitability is defined as the prey size giving the maximum energygain per unit handling time (Stephens & Krebs, 1986). For a 45-mm

Changes in the foraging behaviour due to variation in the body size of the three-spined stickleback Gasterosteus aculeatus were investigated. All sizes of fish had a high probability of attacking prey whenever encountered. The probability of eating the prey increased with the size of the fish, as the larger fish had larger jaws and a greater stomach capacity. Therefore, as fish increased in size there was an increase in the probability of successful prey capture. The level of satiation did not have an effect on the prey handling time, which is contrary to other studies and is probably a result of the large prey sizes. The physical size of the prey meant that the handling times were long regardless of the motivational level of the fish. The larger fish took in more energy and at a faster rate, although the time to reach satiation was similar for all fish sizes. The advantage that large fish appear to have in successfully gaining large prey is negated by their greater metabolic requirement. The changes in feeding performance induced by small increases in body size could have important consequences for intraspecific competition, habitat Use and risk of predation.

Competition between pairs of stickleback was studied to investigate the effects of fish size and prey size on the feeding behaviour and competitive ability of the fish when single prey items were encountered sequentially. All the fish had a high probability of attacking the prey encountered. A fish with a high probability of being first to handle the prey had a high probability of ingesting it only when the prey was the smaller of the two prey sizes offered. With the larger prey, food gain was predicted not by the first to handle but by the jaw size of the fish. Encounter with a larger prey resulted in each fish attempting to capture it more often. This was due to the larger prey being visible for longer as it had to be manipulated before being swallowed. Even when prey were ingested and hence not visible, the unsuccessful competitor remained close by for approximately 7 s. The probability of eating any prey encountered was dependent on the phenotypic properties of the individual fish. A fast reacting fish with large jaws was able to reach its daily energy requirement regardless of the encounter rate with any prey size. Competitive ability was therefore a function of the fish, ability to reach the prey first, the capacity of the jaw apparatus to ingest the prey and prey encounter rate. When the pairs of fish encountered a high proportion of large prey, a generalist feeding strategy was the best option. The results can be applied to current foraging models, in particular to extending the sequential encounter model.

We describe 15 polymorphic dinucleotide microsatellite loci in the black-and-gold chromis, Neoglyphidodon nigroris (Cuvier: Teleostei: Pomacentridae). Microsatellites were isolated from a partial genomic library that was enriched for CA repeat motifs. The 15 loci yielded between two and 23 alleles per locus in a sample of 16 fish from two forereef sites off the island of Hoga, Wakatobi National Park, Indonesia. Observed and expected heterozygosities varied from 0.13 to 1.00 and 0.24 to 0.98, respectively. These markers should allow us to discriminate between closely related individuals and also to assess the connectedness of populations of N. nigroris that inhabit different reefs.

To investigate the role of multiparametric magnetic resonance (MR) imaging in the evaluation of response to platinum-based neoadjuvant chemotherapy in advanced ovarian cancer and to compare imaging parameters between primary ovarian mass and metastatic disease.Evaluable patients suspected of having advanced ovarian carcinoma were enrolled in a prospective protocol-driven study. Research ethics committee approval and written informed consent were obtained. Multiparametric MR imaging (diffusion-weighted MR imaging, dynamic contrast material-enhanced [DCE] MR imaging, and hydrogen 1 MR spectroscopy) was performed with a 3.0-T wholebody MR imaging system. Three marker lesions-primary ovarian mass, omental cake, and peritoneal deposit-were outlined by a radiologist on apparent diffusion coefficient (ADC) and vascular signal fraction (VSF) maps and on DCE MR images. Comparisons of mean ADC, mean VSF, DCE MR imaging parameters, and choline concentration between responders and nonresponders were based on Response Evaluation Criteria in Solid Tumors and CA-125 criteria.Twenty-two patients were evaluable. The mean ADC for peritoneal metastases was lower than that for ovarian (P = .015) and omental (P = .006) sites. There were no differences in pretreatment DCE MR imaging parameters between tumor sites. After treatment, responders showed a significantly larger increase in ADC (P = .021) and fractional volume of the extravascular extracellular space (v(e)) (P = .025) of ovarian lesions compared with nonresponders, but there was no change in ADC at other sites. Pre- and posttreatment values of choline concentration of ovarian lesions were lower in responders (P = .025) than in nonresponders (P = .010).The significant differences in baseline ADCs among primary ovarian cancer, omental cake, and peritoneal deposits indicate that diffusivity profiles may be tumor-site dependent, suggesting biologic heterogeneity of disease. ADC and v(e) parameters correlated with the cytotoxic effects of platinum-based therapy and may be useful response markers, while choline concentration predicted but did not reflect response.

There is an urgent need to obtain information on the effects of underwater sound on marine fish due to imminent policy drivers, e.g., the European Union Marine Strategy Framework Directive, on one hand and the increasingly noisy activities in the marine environment on the other. Yet studying the influence of sound, particularly on the behavior of fish, is a challenging task. Studies in tanks can suffer problems with the reflection of sound, especially at the low frequencies that are most important for fish. Studies in the field are often limited because the observation of fish is very complicated.

Abstract. This study investigated changes in the feeding behaviour and prey choice of threespine stickleback, Gasterosteus aculeatus , of different body sizes, in response to increasing prey size and stomach fullness of the fish. Within the behavioural feeding sequence, a decision to attack and a decision to eat the prey were made by the fish. Smaller fish were more likely to stop in midwater during the attack and to manipulate the prey when handling it. Larger fish were more likely to attack and eat the prey. The probability of success, however, decreased with larger prey. Success also decreased with increasing stomach fullness when prey larger than the prey width:mouth width (PW:MW) ratio of 0·6 were encountered. Regardless of fish or prey size, there was a constant handling time of approximately 3 s during which the fish decided to eat. The time taken to handle and eat a prey decreased for larger fish and rose with larger prey. Spitting frequency increased with prey size and spitting was always required for prey greater than the 0·6 PW:MW ratio. This corresponded to a preference for prey oriented head first and ventral side up. Prey closest to the 0·6 PW:MW ratio were the largest prey that could be eaten with little change in the time cost over all levels of stomach fullness. These prey, therefore, gave the fish the best energy return per unit cost, except when the stomach was empty, as larger prey represented a bigger energy return for the same time cost giving them a greater effective profitability. The morphological relationship between a predator and prey determines the resulting feeding behaviour and prey choice, although this choice also depends on the predator's need to acquire food.

Purpose Previous studies reporting relaxation times within atherosclerotic plaque have typically used dedicated small-bore high-field systems and small sample sizes. This study reports quantitative T 1 , T 2 and T 2 ⁎ relaxation times within plaque tissue at 1.5 T using spatially co-matched histology to determine tissue constituents. Methods Ten carotid endarterectomy specimens were removed from patients with advanced atherosclerosis. Imaging was performed on a 1.5-T whole-body scanner using a custom built 10-mm diameter receive-only solenoid coil. A protocol was defined to allow subsequent computation of T 1 , T 2 and T 2 ⁎ relaxation times using multi-flip angle spoiled gradient echo, multi-echo fast spin echo and multi-echo gradient echo sequences, respectively. The specimens were subsequently processed for histology and individually sectioned into 2-mm blocks to allow subsequent co-registration. Each imaging sequence was imported into in-house software and displayed alongside the digitized histology sections. Regions of interest were defined to demarcate fibrous cap, connective tissue and lipid/necrotic core at matched slice-locations. Relaxation times were calculated using Levenberg-Marquardt's least squares curve fitting algorithm. A linear-mixed effect model was applied to account for multiple measurements from the same patient and establish if there was a statistically significant difference between the plaque tissue constituents. Results T 2 and T 2 ⁎ relaxation times were statistically different between all plaque tissues ( P =.026 and P =.002 respectively) [T 2 : lipid/necrotic core was lower 47±13.7 ms than connective tissue (67±22.5 ms) and fibrous cap (60±13.2 ms); T 2 ⁎ : fibrous cap was higher (48±15.5ms) than connective tissue (19±10.6 ms) and lipid/necrotic core (24±8.2 ms)]. T 1 relaxation times were not significantly different ( P =.287) [T 1 : Fibrous cap: 933±271.9 ms; connective tissue (1002±272.9 ms) and lipid/necrotic core (1044±304.0 ms)]. We were unable to demarcate hemorrhage and calcium following histology processing. Conclusions This study demonstrates that there is a significant difference between qT 2 and qT 2 ⁎ in plaque tissues types. Derivation of quantitative relaxation times shows promise for determining plaque tissue constituents.

Androgen deprivation therapy (ADT) is a key primary treatment for advanced and metastatic prostate cancer and is an important neoadjuvant before radiotherapy. We evaluated 3.0 T dynamic contrast-enhanced MRI and diffusion-weighted (DW) MRI in monitoring ADT response. Twenty-three consecutive patients with prostate cancer treated by primary ADT were included. Imaging was performed at baseline and 3 months posttreatment with ADT. After 3 months therapy there was a significant reduction in all dynamic contrast-enhanced MRI parameters measured in tumor regions of interest (K(trans), k(ep), v(p), IAUGC-90); P < 0.001. Areas of normal-appearing peripheral zone showed no significant change; P = 0.285-0.879. Post-ADT, there was no significant change in apparent diffusion coefficient values in tumors, whilst apparent diffusion coefficient values significantly decreased in areas of normal-appearing peripheral zone, from 1.786 × 10(-3) mm(2) /s to 1.561 × 10(-3) mm(2) /s; P = 0.007. As expected the median Prostate-Specific Antigen (PSA) significantly reduced from 30 ng/mL to 1.5 ng/mL posttreatment, and median prostate volume dropped from 47.6 cm(3) to 24.9 cm(3) ; P < 0.001. These results suggest that dynamic contrast-enhanced MRI and diffusion-weighted MRI offer different information but that both could prove useful adjuncts to the anatomical information provided by T2-weighted imaging. dynamic contrast-enhanced as a marker of angiogenesis may help demonstrate ADT resistance and diffusion-weighted imaging may be more accurate in determining presence of tumor cell death versus residual tumor.

(1993). Choosing prey size: A comparison of static and dynamic foraging models for predicting prey choice by fish. Marine Behaviour and Physiology: Vol. 23, Behavioural Ecology of Fishes, pp. 91-104.