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Nutrient capture and sustainable yield maximized by a gear modification in artisanal fishing traps
Get PDFCoral reef artisanal fisheries are an important source of nutrition and economic wellbeing for coastal communities, but their management is subject to conflicts and tradeoffs between short-term food security benefits and long-term ecological function. One potential tradeoff is between nutrient capture and fish yields, where targeting small, nutrient-dense species may be more valuable for food security than maximizing fish yields, which is more closely aligned with supporting biodiversity and ecological function. We explored these potential tradeoffs by comparing two similar gears: traditional African basket traps and traps modified with an escape gap. Traps without escape gaps captured a higher frequency of fish with body sizes below their estimated lengths at maximum sustainable yield than gated traps. Estimates of nutrient yields for six micronutrients among the 208 captured species indicated high hump-shaped relationships for gated traps and low and linear positive relationships for traditional traps. Maximum nutrients in gated traps frequently corresponded to body sizes at maximum sustainable yield. Daily capture rates of nutrients were above daily needs more often in gated than traditional traps, but calcium values were low in both trap designs. Gated traps were more likely to capture species with unique and potentially important functional traits, including browsing herbivores, which could have negative effects on ecological functions and reef recovery. However, gated traps also catch fewer immature fish and fewer predators. Our results indicate that nutrient yields can be maximized while using a gear that captures larger and more sustainable body sizes in coral reef artisanal fisheries. Preferential targeting of nutrient-dense fishes is only one of many metrics for evaluating a nutrition-centered management strategy and may only be a management target in specific contexts
Groundwater quality: Global threats, opportunities and realising the potential of groundwater
No full textGroundwater is a critical resource enabling adaptation due to land use change, population growth, environmental degradation, and climate change. It can be a driver of change and adaptation, as well as effectively mitigate impacts brought about by a range of human activities. Groundwater quality is key to assessing groundwater resources and we need to improve our understanding and coverage of groundwater quality threats if we are to use groundwater sustainably to not further burden future generations by limiting resources and/or increasing treatment or abstraction costs. Good groundwater quality is key to progress on a range of Sustainable Development Goals, but achievement of those goals most affected by groundwater contamination is often hindered by of a lack of resources to enable adaptation. A range of threats to groundwater quality exist, both natural and anthropogenic, which may constrain groundwater use. However, groundwater often provides good quality water for a range of purposes and is the most important water resource in many settings. This special issue explores some of the key groundwater quality challenges we face today as well as the opportunities good groundwater quality and treatment solutions bring to enhance safe groundwater use. Legacy anthropogenic contaminants and geogenic contaminants may be well documented in certain places, such as N America, Europe and parts of Asia. However, there is a real issue of data accessibility in some regions, even for more common contaminants. This paucity of information can restrict our understanding and ability to manage and protect groundwater sources. Compared to surface water quality, large scale assessments for groundwater quality are still scarce and often rely on inadequate data sets. Better access to existing data sets and more research is needed on many groundwater quality threats. Identification and quantification of these threats will support the wise use and protection of this subsurface resource, allow society to adequately address future challenges, and help communities realise the full potential of groundwater
Peroxone activated persulfate oxidation of 1,4-Dioxane under column scale conditions
No full textThe research presented herein investigates a peroxone activated persulfate (PAP) oxidant, commercialized under the trade name OxyZone®, and its effects on 1,4-Dioxane (dioxane) contaminated water under column scale conditions in the presence of porous material. There is a limited understanding of the underlying processes that govern PAP oxidation, including the oxidation rates in the presence of aquifer material, and how these reactions proceed once the oxidant is injected into a contaminant plume. Initial batch experiments with porous material (e.g. sand) provided data on the reaction rates of dioxane oxidation as a function of the oxidant: contaminant ratio. The observed degradation rates were approximately 4 times lower than those reported for aqueous solutions containing no porous media. Subsequent column experiments simulated two PAP injections schemes along the flowpath of a dioxane plume to study if the injection of one oxidant slug may yield different results than injecting the same oxidant volume at two separate locations. The injection of one oxidant slug was found more effective, resulting in near complete destruction of dioxane over a prolonged time at a rate more than an order of magnitude greater than in the two-slug injection scenario. Tracer test results suggest that the prolonged oxidant reactivity was in part caused by the high density of the injected oxidant solution. Overall, the results underline the importance of accounting for the properties of both the oxidant solution and the porous material when considering the injection of PAP oxidant into an impacted aquifer
Multi-scale Computer Modeling for Advanced Pharmaceutical Manufacturing
Get PDFDrug development and manufacturing are one of the significant processes in the pharmaceutical industry. Various computational methods have been dramatically reducing the time and cost of drug discovery and development. Improved algorithms, overgrowing powerful computing architectures and the accelerating growth of rich data sets are driving advances in multiscale modelling methods capable of bridging chemical and biological complexity from the atom to the manufacturing scale. In this talk, the roles of physics based multiscale modeling and simulations in the areas of (i) continuous manufacturing of complex dosage forms and (ii) electrostatic behavior of pharmaceutical powders will be discussed. These research efforts yielded interesting results that provided insight into the effects of various material properties and operating conditions on the success of pharmaceutical processes
Newly Revised Study of Daily Time Series Data Analysis of Market Prices
Get PDFThe purpose of this paper is to clarify the existence of time series characteristics of daily stock prices of securities marketed on organized exchanges. This study differs from previous studies where the focus was on index numbers of daily stock market prices rather than the actual prices of traded securities. Furthermore, this study is important because of the theory of market efficiency and its application to short term forecasting of closing prices of traded securities
Love thy neighbor (or not): Regionalism and support for the use of offshore wind energy by others
No full textDistributive fairness influences public acceptance of renewable energy technologies. Concerns about distributive fairness contribute to opposition to export of electricity and public preferences for electricity to be consumed near its production. Distributional issues are relevant to offshore wind energy development, where the coastal communities nearest to the developments may see none of the jobs, economic development, or profits associated with development, with undersea cables often delivering the electricity to faraway places. In a survey of coastal residents in the northeast United States, we find differences in support for use of offshore wind energy in their own state. Support for electricity use by other states, however, reveals the effects of subnational regionalism. Residents of Rhode Island prefer the use of electricity produced off their shores by the state of Massachusetts over New York; residents of New Hampshire prefer for Maine to consume energy over Massachusetts. These findings portend conflicts over the transmission of electricity as offshore wind energy development expands in U.S. and has implications for all renewable energy transmission that crosses regional boundaries
Lessons learned from a natural resource disaster: The long-term impacts of the Long Island Sound lobster die-off on individuals and communities
No full textIn 1999, the Long Island Sound American lobster population experienced a severe mortality event, resulting in the abrupt demise of this culturally and economically important fishery. While studies have investigated the environmental and biological causes and effects of this event, little has been done to understand its social, economic, psychological, and cultural impacts. In this study, we interviewed lobstermen and seafood wholesalers who were affected by the die-off to understand their experiences and perceptions of impacts, and factors influencing their capacity to adapt. We compared our findings to those in the sole socio-economic impact assessment conducted in the aftermath of the event. Our findings show that the die-off had profound and lasting impacts on individuals, their families, and communities with little evidence of a successful recovery. The lack of effective and comprehensive recovery or assistance plans, combined with challenges impeding fishery diversification, significantly hindered the ability of lobstermen to adapt. The lessons learned from this case study can inform future action to address impacts and maximize adaptive capacity in fishing communities experiencing environmental changes and shifts in species distributions due to climate change and other anthropogenic factors
Rapidly declining body size in an insectivorous bat is associated with increased precipitation and decreased survival
Get PDFReduced food availability is implicated in declines in avian aerial insectivores, but the effect of nutritional stress on mammalian aerial insectivores is unclear. Unlike birds, insectivorous bats provision their young through lactation, which might protect nursing juveniles when prey availability is low but could increase the energetic burden on lactating females. We analyzed a 15-year capture–mark–recapture data set from 5312 individual little brown myotis (Myotis lucifugus) captured at 11 maternity colonies in northwestern Canada, to test the hypothesis that nutritional stress is impacting these mammalian aerial insectivores. We used long-bone (forearm [FA]) length as a proxy for relative access to nutrition during development, and body mass as a proxy for access to nutrition prior to capture. Average FA length and body mass both decreased significantly over the study period in adult females and juveniles, suggesting decreased access to nutrition. Effect sizes were very small, similar to those reported for declining body size in avian aerial insectivores. Declines in juvenile body mass were only observed in individuals captured in late summer when they were foraging independently, supporting our hypothesis that lactation provides some protection to nursing young during periods of nutritional stress. Potential drivers of the decline in bat size include one or both of (1) declining insect (prey) abundance, and (2) declining prey availability. Echolocating insectivorous bats cannot forage effectively during rainfall, which is increasing in our study area. The body mass of captured adult females and juveniles in our study was lower, on average, after periods of high rainfall, and higher after warmer-than-average periods. Finally, survival models revealed a positive association between FA length and survival, suggesting a fitness consequence to declines in body size. Our study area has not yet been impacted by bat white-nose syndrome (WNS), but research elsewhere has suggested that fatter bats are more likely to survive infection. We found evidence for WNS-independent shifts in the body size of little brown myotis, which can inform studies investigating population responses to WNS. More broadly, the cumulative effects of multiple stressors (e.g., disease, nutritional stress, climate change, and other pressures) on mammalian aerial insectivores require urgent attention
Developing a method for quantifying hip joint angles and moments during walking using neural networks and wearables
Get PDFQuantifying hip angles/moments during gait is critical for improving hip pathology diagnostic and treatment methods. Recent work has validated approaches combining wearables with artificial neural networks (ANNs) for cheaper, portable hip joint angle/moment computation. This study developed a Wearable-ANN approach for calculating hip joint angles/moments during walking in the sagittal/frontal planes with data from 17 healthy subjects, leveraging one shin-mounted inertial measurement unit (IMU) and a force-measuring insole for data capture. Compared to the benchmark approach, a two hidden layer ANN (n = 5 nodes per layer) achieved an average rRMSE = 15% and R2=0.85 across outputs, subjects and training rounds
The effects of training, acute exercise and dietary fatty acid composition on muscle lipid oxidative capacity in European starlings
No full textMigratory birds undergo seasonal changes to muscle biochemistry. Nonetheless, it is unclear to what extent these changes are attributable to the exercise of flight itself versus endogenous changes. Using starlings (Sturnus vulgaris) flying in a wind tunnel, we tested the effects of exercise training, a single bout of flight and dietary lipid composition on pectoralis muscle oxidative enzymes and lipid transporters. Starlings were either unexercised or trained over 2 weeks to fly in a wind tunnel and sampled either immediately following a long flight at the end of this training or after 2 days recovery from this flight. Additionally, they were divided into dietary groups that differed in dietary fatty acid composition (high polyunsaturates versus high monounsaturates) and amount of dietary antioxidant. Trained starlings had elevated (19%) carnitine palmitoyl transferase and elevated (11%) hydroxyacyl-CoA dehydrogenase in pectoralis muscle compared with unexercised controls, but training alone had little effect on lipid transporters. Immediately following a long wind-tunnel flight, starling pectoralis had upregulated lipid transporter mRNA (heart-type fatty acid binding protein, H-FABP, 4.7-fold; fatty acid translocase, 1.9-fold; plasma membrane fatty acid binding protein, 1.6-fold), and upregulated H-FABP protein (68%). Dietary fatty acid composition and the amount of dietary antioxidants had no effect on muscle catabolic enzymes or lipid transporter expression. Our results demonstrate that birds undergo rapid upregulation of catabolic capacity that largely becomes available during flight itself, with minor effects due to training. These effects likely combine with endogenous seasonal changes to create the migratory phenotype observed in the wild