Chronic administration of Glucagon-like peptide-1 receptor agonists improves trabecular bone mass and architecture in ovariectomised mice

Some anti-diabetic therapies can have adverse effects on bone health and increase fracture risk. In this study, we tested the skeletal effects of chronic administration of two Glucagon-like peptide-1 receptor agonists (GLP-1RA), increasingly used for type 2 diabetes treatment, in a model of osteoporosis associated bone loss and examined the expression and activation of GLP-1R in bone cells. Mice were ovariectomised (OVX) to induce bone loss and four weeks later they were treated with Liraglutide (LIR) 0.3 mg/kg/day, Exenatide (Ex-4) 10 μg/kg/day or saline for four weeks. Mice were injected with calcein and alizarin red prior to euthanasia, to label bone-mineralising surfaces. Tibial micro-architecture was determined by micro-CT and bone formation and resorption parameters measured by histomorphometric analysis. Serum was collected to measure calcitonin and sclerostin levels, inhibitors of bone resorption and formation, respectively. GLP-1R mRNA and protein expression were evaluated in the bone, bone marrow and bone cells using RT-PCR and immunohistochemistry. Primary osteoclasts and osteoblasts were cultured to evaluate the effect of GLP-1RA on bone resorption and formation in vitro. GLP-1RA significantly increased trabecular bone mass, connectivity and structure parameters but had no effect on cortical bone. There was no effect of GLP-1RA on bone formation in vivo but an increase in osteoclast number and osteoclast surfaces was observed with Ex-4. GLP-1R was expressed in bone marrow cells, primary osteoclasts and osteoblasts and in late osteocytic cell line. Both Ex-4 and LIR stimulated osteoclastic differentiation in vitro but slightly reduced the area resorbed per osteoclast. They had no effect on bone nodule formation in vitro. Serum calcitonin levels were increased and sclerostin levels decreased by Ex-4 but not by LIR. Thus, GLP-1RA can have beneficial effects on bone and the expression of GLP-1R in bone cells may imply that these effects are exerted directly on the tissue

A novel high efficiency electro-hydrostatic flight simulator motion system

Modern flight training simulators must be equipped with long stroke six degree-of-freedom motion systems that have high dynamic response. For many years electro-hydraulic actuators in a Stewart platform configuration have been found to best meet the performance requirements. However, valve-controlled actuators are very inefficient leading to a large power consumption, and also the need for a substantial cooling system to remove waste energy (heat) from the hydraulic oil. This paper describes a new design of motion system that uses a controlled brushless motor for each actuator, with power transmission via directly driven pumps to conventional simulator hydraulic cylinders. Accumulators are used to store and later recycle high pressure oil when actuators retract. In this way, power consumption has been dramatically reduced (for example from 45kW to 5kW during one representative motion waveform), while retaining the proven characteristics of the cylinder drive. Power consumption is lower, by a factor of between 2 and 4, than an equivalent all-electric solution. The motion system will be supplied for the first time with Boeing 787 simulators to be delivered in 2008. Design details are given in this paper, together with predicted and measured power consumption during a variety of representative cyclic motions

Three dimensional tracking of a wide-ranging marine predator: flight heights and vulnerability to offshore wind farms

1. A large increase in offshore wind turbine capacity is anticipated in the next decade, raising concerns about possible adverse impacts on birds as a result of collision risk. Birds’ flight heights greatly influence this risk yet height estimates are currently available only using methods such as radar or ship-based observations over limited areas. 2. Bird-borne data-loggers have the potential to provide improved estimates of collision risk and here, we use data from GPS-loggers and barometric pressure-loggers to track the three-dimensional movements of northern gannets rearing chicks at a large colony in SE Scotland (Bass Rock), located < 50km from several major wind farm developments with recent planning consent. We estimate the foraging ranges and densities of birds at sea, their flight heights during different activities and the spatial variation in height during trips. We then use these data in collision-risk models to explore how the use of different methods to determine flight height affects the predicted risk of birds colliding with turbines. 3. Gannets foraged in and around planned wind farm sites. The probability of flying at collision- risk height was low during commuting between colonies and foraging areas (median height 12m) but was greater during periods of active foraging (median height 27m), and we estimate that ~1500 breeding adults from Bass Rock could be killed by collision with wind turbines at two planned sites in the Firth of Forth region each year. This is up to 12 times potential mortality predicted using other available flight height estimates. 4. Synthesis & Applications: The use of conventional flight height estimation techniques resulted in large underestimates of the numbers of birds at risk of colliding with wind turbines. Hence we recommend using GPS and barometric tracking to derive activity-specific and spatially-explicit flight heights and collision risks. Our predictions of potential mortality approached levels at which long-term population viability could be threatened, highlighting a need for further data to refine estimates of collision risks and sustainable mortality thresholds. We also advocate raising the minimum permitted clearance of turbine blades at sites with high potential collision risk from 22m 51 to 30m above sea level

Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets.

Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called 'Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20-30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures

Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets.

Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called 'Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20-30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures

Passerine Birds Breeding under Chronic Noise Experience Reduced Fitness

Background Fitness in birds has been shown to be negatively associated with anthropogenic noise, but the underlying mechanisms remain obscure. It is however crucial to understand the mechanisms of how urban noise impinges on fitness to obtain a better understanding of the role of chronic noise in urban ecology. Here, we examine three hypotheses on how noise might reduce reproductive output in passerine birds: (H1) by impairing mate choice, (H2) by reducing territory quality and (H3) by impeding chick development. Methodology/Principal Findings We used long-term data from an island population of house sparrows, Passer domesticus, in which we can precisely estimate fitness. We found that nests in an area affected by the noise from large generators produced fewer young, of lower body mass, and fewer recruits, even when we corrected statistically for parental genetic quality using a cross-fostering set-up, supporting H3. Also, individual females provided their young with food less often when they bred in the noisy area compared to breeding attempts by the same females elsewhere. Furthermore, we show that females reacted flexibly to increased noise levels by adjusting their provisioning rate in the short term, which suggests that noise may be a causal factor that reduces reproductive output. We rejected H1 and H2 because nestbox occupancy, parental body mass, age and reproductive investment did not differ significantly between noisy and quiet areas. Conclusions/Significance Our results suggest a previously undescribed mechanism to explain how environmental noise can reduce fitness in passerine birds: by acoustically masking parent–offspring communication. More importantly, using a cross-fostering set-up, our results demonstrate that birds breeding in a noisy environment experience significant fitness costs. Chronic noise is omnipresent around human habitation and may produces similar fitness consequences in a wide range of urban bird species

The feasibility of milkfish (Chanos chanos) aquaculture in Solomon Islands

Fish is crucial to food and nutrition security in Solomon Islands, and demand is expected to increase due to a growing population. However, it is projected that current capture fisheries production will not meet this growing demand. Aquaculture has the potential to mitigate the capture fishery shortfall, and the Government of Solomon Islands is prioritizing aquaculture as a solution to meet future food and income needs. Aquaculture in Solomon Islands is still in early development. Mozambique tilapia (Oreochromis mossambicus) is farmed for household consumption, but its prolific reproductive rate and resulting slow growth limit its potential as a commercial aquaculture species. More productive fish species that are not indigenous to Solomon Islands but are successfully farmed overseas could be introduced; however, such a decision needs to take into account the potential ecological or social impacts. For land-based pond aquaculture, the only indigenous species that has been farmed extensively elsewhere is milkfish (Chanos chanos). This report presents a feasibility assessment for milkfish farming in Solomon Islands. It synthesizes the current knowledge about milkfish farming and presents results of a 4-year study on the potential for milkfish aquaculture in Solomon Islands

Spooked

There’s always something a bit scary about a ghost story. Somehow, though, when you read a collection of them you’re expecting to meet a spook or two. It takes a little more effort to frighten the reader. We hope we’ve managed to do just that with this bunch of tales and our striking cover. We hope as well you’ll find the stories as different from each other as they are from the normal ghost story. You’ll come across some old friends amongst the authors in this volume. Bridge House is beginning to es-tablish a brand and we have several writers now who have the measure of what we’re looking for. You’ll also meet some new names and writing styles. We’re sure both will please. And now to the ghosts…. They too have a life of their own … precisely drawn by our authors. It’s that time of year isn’t it? When the nights are getting longer, the days are getting shorter, when strange shadows lurk and you begin to hear noises you don’t understand. We have traditional ghosts, more subtle ghosts, naughty ghosts, nice ghost, nasty ghost and in one or two of our stories it’s a little difficult to work out who is haunting whom. Stoke up the fire, sit back, enjoy and prepare to be: Spooked

Sexual Size Dimorphism and Body Condition in the Australasian Gannet

Funding: The research was financially supported by the Holsworth Wildlife Research Endowment. Acknowledgments We thank the Victorian Marine Science Consortium, Sea All Dolphin Swim, Parks Victoria, and the Point Danger Management Committee for logistical support. We are grateful for the assistance of the many field volunteers involved in the study.Peer reviewedPublisher PD