Assessing the cumulative exposure of wildlife to offshore wind energy development.

Governments and developers are pursuing offshore wind energy to address climate change, but multiple wind farms may cumulatively affect wildlife populations. Assessments of cumulative effects must first calculate the cumulative exposure of a wildlife population to a hazard and then estimate how the exposure will affect the population. Our research responds to the first need by developing a model designed to assess how different wind farm siting scenarios cumulatively expose wildlife. The model assesses cumulative exposure by identifying all locations where development could occur, placing wind farms within this suitability layer, and then overlaying wind engineering and biological data sets. The first model output is a graphical representation of how offshore wind farm siting decisions affect wildlife cumulative exposure. The second output is an index that ranks which offshore wind farm siting decisions will have the greatest influence on wildlife cumulative exposure. Together these outputs provide stakeholders with valuable information that could be used to guide siting and management decisions.

Changes in mercury exposure of marine birds breeding in the Gulf of Maine, 2008-2013.

Mercury is a potent contaminant that can disrupt an organism's behavior and physiology, ultimately affecting reproductive success. Over the last 100 years, environmental deposition of anthropogenic sourced mercury has increased globally, particularly in the U.S. Northeast region. Marine birds are considered effective bioindicators of ecosystem health, including persistent marine contaminants. Goodale et al. (2008) found that mercury exposure exceeded adverse effects levels in some marine bird species breeding across the Gulf of Maine. We re-examined mercury contamination in four species identified as effective bioindicators. Compared with the previous sampling effort, inshore-feeding species showed significant increases in mercury exposure, while one pelagic-feeding species remained stable. This suggests that a major shift may have occurred in methylmercury availability in inshore waters of the Gulf of Maine. Understanding environmental mercury trends in the Gulf of Maine, and its significance to marine birds and other taxa will require a dedicated, standardized, long-term monitoring scheme.

Plasma firocoxib concentrations after intra-articular injection of autologous conditioned serum prepared from firocoxib positive horses.

Orthobiologics such as autologous conditioned serum (ACS) are often used to treat joint disease in horses. Because ACS is generated from the horse's own blood, any medication administered at the time of preparation would likely be present in stored ACS, which could lead to an inadvertent positive drug test following intra-articular (IA) injection. The main objective of this study was to determine if ACS prepared from firocoxib positive horses could result in detectable plasma concentrations of the drug following IA injection. Firocoxib was administered to six horses at 0.1mg/kg PO twice at a 24h interval. Blood was obtained at 4h following the second dose and transferred to a separate syringe (Arthrex IRAP II) for ACS preparation. Plasma and ACS concentrations of firocoxib were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). When horses were confirmed firocoxib negative, 7.5mL of ACS was injected into both tarsocrural joints. Blood samples were collected at 0, 4, 8, 12, 24, and 48h, and firocoxib concentration was measured. Mean (±standard error of the mean, SEM) plasma concentration of firocoxib 4h following the second dose was 33.3±4.72ng/mL. Mean (±SEM) firocoxib concentration in ACS was 35.4±4.47ng/mL. Fourteen days following the second and last dose of firocoxib, mean plasma concentration was below the lower limit of detection (LOD=1ng/mL) in all horses. Following IA injection of ACS, plasma concentrations of firocoxib remained below LOD at all times in all horses. ACS generated from horses with therapeutic plasma concentrations of firocoxib did not contain sufficient firocoxib to lead to a positive plasma drug test following IA administration.

Weightlifting exercise and the size-weight illusion.

In the size-weight illusion (SWI), large objects feel lighter than equally weighted small objects. In the present study, we investigated whether this powerful weight illusion could influence real-lift behavior-namely, whether individuals would perform more bicep curls with a dumbbell that felt subjectively lighter than with an identically weighted, but heavier-feeling, dumbbell. Participants performed bicep curls until they were unable to continue with both a large, light-feeling 5-lb dumbbell and a smaller, heavy-feeling 5-lb dumbbell. No differences emerged in the amounts of exercise that participants performed with each dumbbell, even though they felt that the large dumbbell was lighter than the small dumbbell. Furthermore, in a second experiment, we found no differences in how subjectively tired participants felt after exercising for a set time with either dumbbell. We did find, however, differences in the lifting dynamics, such that the small dumbbell was moved at a higher average velocity and peak acceleration. These results suggest that the SWI does not appear to influence exercise outcomes, suggesting that perceptual illusions are unlikely to affect one's ability to persevere with lifting weights.

Neural correlates of motion processing through echolocation, source hearing, and vision in blind echolocation experts and sighted echolocation novices.

We have shown in previous research (Thaler L, Arnott SR, Goodale MA. PLoS One 6: e20162, 2011) that motion processing through echolocation activates temporal-occipital cortex in blind echolocation experts. Here we investigated how neural substrates of echo-motion are related to neural substrates of auditory source-motion and visual-motion. Three blind echolocation experts and twelve sighted echolocation novices underwent functional MRI scanning while they listened to binaural recordings of moving or stationary echolocation or auditory source sounds located either in left or right space. Sighted participants' brain activity was also measured while they viewed moving or stationary visual stimuli. For each of the three modalities separately (echo, source, vision), we then identified motion-sensitive areas in temporal-occipital cortex and in the planum temporale. We then used a region of interest (ROI) analysis to investigate cross-modal responses, as well as laterality effects. In both sighted novices and blind experts, we found that temporal-occipital source-motion ROIs did not respond to echo-motion, and echo-motion ROIs did not respond to source-motion. This double-dissociation was absent in planum temporale ROIs. Furthermore, temporal-occipital echo-motion ROIs in blind, but not sighted, participants showed evidence for contralateral motion preference. Temporal-occipital source-motion ROIs did not show evidence for contralateral preference in either blind or sighted participants. Our data suggest a functional segregation of processing of auditory source-motion and echo-motion in human temporal-occipital cortex. Furthermore, the data suggest that the echo-motion response in blind experts may represent a reorganization rather than exaggeration of response observed in sighted novices. There is the possibility that this reorganization involves the recruitment of "visual" cortical areas.

What is the best fixation target? The effect of target shape on stability of fixational eye movements.

People can direct their gaze at a visual target for extended periods of time. Yet, even during fixation the eyes make small, involuntary movements (e.g. tremor, drift, and microsaccades). This can be a problem during experiments that require stable fixation. The shape of a fixation target can be easily manipulated in the context of many experimental paradigms. Thus, from a purely methodological point of view, it would be good to know if there was a particular shape of a fixation target that minimizes involuntary eye movements during fixation, because this shape could then be used in experiments that require stable fixation. Based on this methodological motivation, the current experiments tested if the shape of a fixation target can be used to reduce eye movements during fixation. In two separate experiments subjects directed their gaze at a fixation target for 17s on each trial. The shape of the fixation target varied from trial to trial and was drawn from a set of seven shapes, the use of which has been frequently reported in the literature. To determine stability of fixation we computed spatial dispersion and microsaccade rate. We found that only a target shape which looks like a combination of bulls eye and cross hair resulted in combined low dispersion and microsaccade rate. We recommend the combination of bulls eye and cross hair as fixation target shape for experiments that require stable fixation.

Two visual systems re-viewed.

The model proposed by the authors of two cortical systems providing 'vision for action' and 'vision for perception', respectively, owed much to the inspiration of Larry Weiskrantz. In the present article some essential concepts inherent in the model are summarized, and certain clarifications and refinements are offered. Some illustrations are given of recent experiments by ourselves and others that have prompted us to sharpen these concepts. Our explicit hope in writing our book in 1995 was to provide a theoretical framework that would stimulate research in the field. Conversely, well-designed empirical contributions conceived within the framework of the model are the only way for us to progress along the route towards a fully fleshed-out specification of its workings.

Practice makes perfect, but only with the right hand: sensitivity to perceptual illusions with awkward grasps decreases with practice in the right but not the left hand.

It has been proposed that the visual mechanisms that control well-calibrated actions, such as picking up a small object with a precision grip, are neurally distinct from those that mediate our perception of the object. Thus, grip aperture in such situations has been shown to be remarkably insensitive to many size-contrast illusions. But most of us have practiced such movements hundreds, if not thousands of times. What about less familiar and unpracticed movements? Perhaps they would be less likely to be controlled by specialized visuomotor mechanisms and would therefore be more sensitive to size-contrast illusions. To test this idea, we asked right-handed subjects to pick up small objects using either a normal precision grasp (thumb and index finger) or an awkward grasp (thumb and ring finger), in the context of the Ponzo illusion. Even though this size-contrast illusion had no effect on the scaling of the precision grasp, it did have a significant effect on the scaling of the awkward grasp. Nevertheless, after three consecutive days of practice, even the awkward grasp became resistant to the illusion. In a follow-up experiment, we found that awkward grasps with the left hand (in right handers) did not benefit from practice and remained sensitive to the illusion. We conclude that the skilled target-directed movements are controlled by visual mechanisms that are quite distinct from those controlling unskilled movements, and that these specialized visuomotor mechanisms may be lateralized to the left hemisphere.

Marine foraging birds as bioindicators of mercury in the Gulf of Maine.

From existing databases, we compiled and evaluated 604 total mercury (Hg) levels in the eggs and blood of 17 species of marine foraging birds from 35 Gulf of Maine islands to provide baseline data and to determine the best tissue, age class, and species for future biomonitoring. While mean Hg levels in most species did not exceed adverse effects thresholds, levels in some individual eggs did; for all species arithmetic mean egg Hg levels ranged from 0.04 to 0.62 (microg/g, wet weight). Piscivorous birds had higher Hg levels than invertivores. Leach's storm-petrel (Oceanodroma leucorhoa), razorbill (Alca torda), and black guillemot (Cepphus grylle) adult blood and egg Hg levels were higher than other species. Our results indicate that adult blood is preferable to chick blood for detecting long-term temporal trends because adult levels are higher and not confounded by metabolic effects. However, since we found that eggs and adult blood are comparable indicators of methylmercury bioavailability, we determined that eggs are the preferred tissue for long-term Hg monitoring because the relative ease in collecting eggs ensures consistent and robust datasets. We suggest specific sampling methods, and based on our results demonstrate that common eider (Somateria mollissima), Leach's storm-petrel, double-crested cormorant, and black guillemot are the most effective bioindicators of Hg of the Gulf of Maine.

Left handedness does not extend to visually guided precision grasping.

In the present study, we measured spontaneous hand preference in a "natural" grasping task. We asked right- and left-handed subjects to put a puzzle together or to create different LEGO models, as quickly and as accurately as possible, without any instruction about which hand to use. Their hand movements were videotaped and hand preference for grasping in ipsilateral and contralateral space was measured. Right handers showed a marked preference for their dominant hand when picking up objects; left handers, however, did not show this preference and instead used their right hand 50% of the time. Furthermore, compared to right handers, left handers used their non-dominant hand significantly more often to pick up objects in ipsilateral as well as contralateral space. Our results show that handedness in left handers does not extend to precision grasp and suggest that right handedness for visuomotor control may reflect a universal left-hemisphere specialization for this class of behaviour.

Efficacy of a single evening dose of syrup containing paracetamol, dextromethorphan hydrobromide, doxylamine succinate and ephedrine sulfate in subjects with multiple common cold symptoms.

OBJECTIVE: The aim of this study was to evaluate the efficacy of a single night-time dose of a syrup containing paracetamol, dextromethorphan hydrobromide, doxylamine succinate and ephedrine sulfate in subjects with multiple cold symptoms. MATERIALS: A syrup containing 15 mg dextromethorphan hydrobromide, 7.5 mg doxylamine succinate, 600 mg paracetamol and 8 mg ephedrine sulfate (Wick MediNait produced by WICK Pharma, Germany, a subsidiary of Procter & Gamble GmbH; test syrup) or placebo (placebo syrup) for oral administration. METHODS: This was a randomized, double-blind, placebo-controlled, multi-center, parallel design study. At enrollment, eligible subjects had to have at least moderate nasal congestion and a runny nose, at least mild cough and at least mild pain with one or more of the following: sore throat, sore chest, headache or body pain/aches. Subjects were randomized into either Group T (test syrup) or Group P (placebo syrup). On the evening of enrollment, subjects rated baseline symptoms, ingested the assigned study product and completed symptom-relief assessments at 3 hours post-dosing. Within one hour of awakening the following morning, subjects completed night-time symptom relief and sleep satisfaction assessments. All symptoms were recorded using an Interactive Voice Response system. Treatment comparisons were made after adjusting for the severity of baseline symptom using analysis of covariance. RESULTS: Of 485 subjects who took the study product, 432 (224 in Group T; 208 in Group P) were evaluable for analysis. For the primary endpoint (composite of nasal congestion/runny nose/cough/pain relief scores 3 hours post-dosing), subjects in Group T had clinically and statistically significantly greater relief than Group P (p = 0.0002). Each individual symptom score also showed statistically significant improvement at this time point (p < or = 0.017). The next morning, Group T continued to show clinically and statistically significant benefits over Group P on the composite score and each of the individual symptoms (p < or = 0.003). Evidence of benefit with the test syrup was also seen in the higher score for overall night-time relief (p < 0.0001) and greater satisfaction on sleep (p = 0.002) compared to placebo syrup. Improvement in individual symptoms after 3 hours was obtained in 16-42% more subjects in Group T than in Group P, whereas the percentage of subjects in Group T having Good or Very Good relief the morning after dosing increased by 25-68% compared to subjects in Group P. 14 subjects (5 in Group T; 9 in Group P) reported AEs but none of these occurred with an incidence greater than 1%. There were no serious AEs. CONCLUSIONS: The results confirm the multisymptom benefit of a single dose of the test syrup containing paracetamol, dextromethorphan hydrobromide, doxylamine succinate and ephedrine sulfate and support its role as an effective and convenient therapy for symptoms of nasal congestion, runny nose, cough and pain/body aches associated with the common cold and for increasing sleep quality disturbed by the common cold.

Comparison of memory- and visually guided saccades using event-related fMRI.

Previous functional imaging studies have shown an increased hemodynamic signal in several cortical areas when subjects perform memory-guided saccades than that when they perform visually guided saccades using blocked trial designs. It is unknown, however, whether this difference results from sensory processes associated with stimulus presentation, from processes occurring during the delay period before saccade generation, or from an increased motor signal for memory-guided saccades. We conducted fMRI using an event-related paradigm that separated stimulus-related, delay-related, and saccade-related activity. Subjects initially fixated a central cross, whose color indicated whether the trial was a memory- or a visually guided trial. A peripheral stimulus was then flashed at one of 4 possible locations. On memory-guided trials, subjects had to remember this location for the subsequent saccade, whereas the stimulus was a distractor on visually guided trials. Fixation cross disappearance after a delay period was the signal either to generate a memory-guided saccade or to look at a visual stimulus that was flashed on visually guided trials. We found slightly greater stimulus-related activation for visually guided trials in 3 right prefrontal regions and right rostral intraparietal sulcus (IPS). Memory-guided trials evoked greater delay-related activity in right posterior inferior frontal gyrus, right medial frontal eye field, bilateral supplementary eye field, right rostral IPS, and right ventral IPS but not in middle frontal gyrus. Right precentral gyrus and right rostral IPS exhibited greater saccade-related activation on memory-guided trials. We conclude that activation differences revealed by previous blocked experiments have different sources in different areas and that cortical saccade regions exhibit delay-related activation differences.

Eye movements tell only half the story.

The dramatic improvements of neglect symptoms after prism adaptation (PA) have been interpreted as evidence that PA reorganizes higher levels of spatial representation. Here the authors demonstrate that while the exploratory eye movements of a patient with neglect were clearly shifted toward the left after PA, he still showed no awareness for the left side of the stimuli he was now actively exploring. PA modulates functions of the parietal lobe, such as eye movement control, but fails to influence the underlying mechanisms of neglect.

"Active" and "passive" learning of three-dimensional object structure within an immersive virtual reality environment.

We used a fully immersive virtual reality environment to study whether actively interacting with objects would effect subsequent recognition, when compared with passively observing the same objects. We found that when participants learned object structure by actively rotating the objects, the objects were recognized faster during a subsequent recognition task than when object structure was learned through passive observation. We also found that participants focused their study time during active exploration on a limited number of object views, while ignoring other views. Overall, our results suggest that allowing active exploration of an object during initial learning can facilitate recognition of that object, perhaps owing to the control that the participant has over the object views upon which they can focus. The virtual reality environment is ideal for studying such processes, allowing realistic interaction with objects while maintaining experimenter control.

Dynamic visual speech perception in a patient with visual form agnosia.

To examine the role of dynamic cues in visual speech perception, a patient with visual form agnosia (DF) was tested with a set of static and dynamic visual displays of three vowels. Five conditions were tested: (1) auditory only which provided only vocal pitch information, (2) dynamic visual only, (3) dynamic audiovisual with vocal pitch information, (4) dynamic audiovisual with full voice information and (5) static visual only images of postures during vowel production. DF showed normal performance in all conditions except the static visual only condition in which she scored at chance. Control subjects scored close to ceiling in this condition. The results suggest that spatiotemporal signatures for objects and events are processed separately from static form cues.

Different spaces and different times for perception and action.

Separate, but interacting, visual systems have evolved in the primate brain for the perception of objects on the one hand and the control of actions directed at those objects on the other. This 'duplex' account of high-level vision suggests that 'reconstructive' approaches and 'purposive-animate-behaviorist' approaches need not be seen as mutually exclusive, but as complementary in their emphases on different aspects of visual function. Indeed, the limitations of one system are the strengths of the other. Perception (which is mediated by the ventral stream of visual projections in primate cortex) delivers a rich and detailed representation of the world, but does not compute the detailed metrics of the scene with respect to the observer. In contrast, the action system (which depends heavily on dorsal-stream projections) delivers accurate metrical information about an object in the required egocentric coordinates for action, but these computations are fleeting and are for the most part limited to the particular goal object that has been selected. Both systems work together in the production of purposive behavior--one system selects the goal object from the visual array, the other carries out the required metrical computations for the goal-directed action.

Manipulating and recognizing virtual objects: where the action is.

In an earlier report (Harman, Humphrey, & Goodale, 1999), we demonstrated that observers who actively rotated three-dimensional novel objects on a computer screen later showed faster visual recognition of these objects than did observers who had passively viewed exactly the same sequence of images of these virtual objects. In Experiment 1 of the present study we showed that compared to passive viewing, active exploration of three-dimensional object structure led to faster performance on a "mental rotation" task involving the studied objects. In addition, we examined how much time observers concentrated on particular views during active exploration. As we found in the previous report, they spent most of their time looking at the "side" and "front" views ("plan" views) of the objects, rather than the three-quarter or intermediate views. This strong preference for the plan views of an object led us to examine the possibility in Experiment 2 that restricting the studied views in active exploration to either the plan views or the intermediate views would result in differential learning. We found that recognition of objects was faster after active exploration limited to plan views than after active exploration of intermediate views. Taken together, these experiments demonstrate (1) that active exploration facilitates learning of the three-dimensional structure of objects, and (2) that the superior performance following active exploration may be a direct result of the opportunity to spend more time on plan views of the object.

Superior performance for visually guided pointing in the lower visual field.

The superior hemiretina in primates and humans has a greater density of ganglion cells than the inferior hemiretina, suggesting a bias towards processing information in the lower visual field (loVF). In primates, this over-representation of the loVF is also evident at the level of striate and extrastriate cortex. This is particularly true in some of the visual areas constituting the dorsal "action" pathway, such as area V6A. Here we show that visually guided pointing movements with the hand are both faster and more accurate when performed in the loVF when compared to the same movements made in the upper visual field (upVF). This was true despite the fact that the biomechanics of the movements made did not differ across conditions. The loVF advantage for the control of visually guided pointing movements is unlikely to be due to retinal factors and may instead reflect a functional bias for controlling skilled movements in this region of space. Possible neural correlates for this loVF advantage for visually guided pointing are discussed.

The dissociation between perception and action in the Ebbinghaus illusion: nonillusory effects of pictorial cues on grasp.

According to a recently proposed distinction [1] between vision for perception and vision for action, visually guided movements should be largely immune to the perceptually compelling changes in size produced by pictorial illusions. Tests of this prediction that use the Ebbinghaus illusion have revealed only small effects of the illusion on grasp scaling as compared to its effect on perception [2-4]. Nevertheless, some have argued that the small effect on grasp implies that there is a single representation of size for both perception and action [5]. Recent findings, however, suggest that the 2-D pictorial elements, such as those comprising illusory backgrounds, can sometimes be treated as obstacles and thereby influence the programming of grasp [6]. The arrangement of the 2-D elements commonly used in previous studies examining the Ebbinghaus illusion could therefore give rise to an effect on grasp scaling that is independent of its effect on perceptual judgements, even though the two effects are in the same direction. We present evidence demonstrating that when the gap between the target and the illusion-making elements in the Ebbinghaus illusion is equidistant across different perceptual conditions (Figure 1a), the apparent effect of the illusion on grasp scaling is eliminated.

Continuous low-level topical heat in the treatment of dysmenorrhea.

OBJECTIVE: To compare the efficacy of topically applied heat for menstrual pain with oral ibuprofen and placebo treatment. METHODS: We conducted a randomized placebo and active controlled (double dummy), parallel study using an abdominal patch (heated or unheated) for approximately 12 consecutive hours per day and oral medication (placebo or ibuprofen 400 mg) three times daily, approximately 6 hours apart for 2 consecutive days. Pain relief and pain intensity were recorded at 17 time points. There was at least 85% power to detect a true one-unit difference in the 2-day pain relief treatment means for comparisons with the unheated patch plus oral placebo group using a one-tailed test at the.05 level of significance, based on an observed within-group standard deviation of 1.147. RESULTS: Eighty-four patients were enrolled and 81 completed the study protocol. Over the 2 days of treatment, the heated patch plus placebo tablet group (mean 3.27, P <.001), the unheated patch plus ibuprofen group (mean 3.07, P =.001), and the combination heated patch plus ibuprofen group (mean 3.55, P <.001) had significantly greater pain relief than the unheated patch plus placebo group (mean 1.95). Greater pain relief was not observed for the combination heated patch plus ibuprofen group compared with the unheated patch plus ibuprofen group (P =.096); however, the time to noticeable pain relief was statistically significantly shorter for the heated patch plus ibuprofen group (median 1.5 hours) compared with the unheated patch plus ibuprofen group (median 2.79 hours, P =.01). CONCLUSION: Continuous low-level topical heat therapy was as effective as ibuprofen for the treatment of dysmenorrhea.