Projecting marine mammal distribution in a changing climate

Climate-related shifts in marine mammal range and distribution have been observed in some populations; however, the nature and magnitude of future responses are uncertain in novel environments projected under climate change. This poses a challenge for agencies charged with management and conservation of these species. Specialized diets, restricted ranges, or reliance on specific substrates or sites (e.g., for pupping) make many marine mammal populations particularly vulnerable to climate change. High-latitude, predominantly ice-obligate, species have experienced some of the largest changes in habitat and distribution and these are expected to continue. Efforts to predict and project marine mammal distributions to date have emphasized data-driven statistical habitat models. These have proven successful for short time-scale (e.g., seasonal) management activities, but confidence that such relationships will hold for multi-decade projections and novel environments is limited. Recent advances in mechanistic modeling of marine mammals (i.e., models that rely on robust physiological and ecological principles expected to hold under climate change) may address this limitation. The success of such approaches rests on continued advances in marine mammal ecology, behavior, and physiology together with improved regional climate projections. The broad scope of this challenge suggests initial priorities be placed on vulnerable species or populations (those already experiencing declines or projected to undergo ecological shifts resulting from climate changes that are consistent across climate projections) and species or populations for which ample data already exist (with the hope that these may inform climate change sensitivities in less well observed species or populations elsewhere). The sustained monitoring networks, novel observations, and modeling advances required to more confidently project marine mammal distributions in a changing climate will ultimately benefit management decisions across time-scales, further promoting the resilience of marine mammal populations

Biomedical and therapeutic applications of biosurfactants

During the last years, several applications of biosurfactants with medical purposes have been reported. Biosurfactants are considered relevant molecules for applications in combating many diseases and as therapeutic agents due to their antibacterial, antifungal and antiviral activities. Furthermore, their role as anti-adhesive agents against several pathogens illustrate their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction of a large number of hospital infections without the use of synthetic drugs and chemicals. Biomedical and therapeutic perspectives of biosurfactants applications are presented and discussed in this chapter

Continuous cultivation of photosynthetic microorganisms: approaches, applications and future trends

The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modelling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed.This research work was supported by the grant SFRH/BPD/98694/2013 (Bruno Fernandes) from Fundacao para a Ciencia e a Tecnologia (Portugal). The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. The authors also thank the Project "BioInd Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" Co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDE

Formation and suppression of defects during heat treatment of BiVO4 photoanodes for solar water splitting

Metal oxide photoelectrodes typically suffer from poor carrier transport properties and extensive carrier recombination, which is caused by the presence of intrinsic or extrinsic defects in the material. Here, the influence of annealing temperature and atmosphere on the formation and suppression of defects in BiVO4 one of the best performing metal oxide photoanodes is elucidated. Annealing in argon has little or no effect on the photoelectrochemical performance due to the competing effects of an increase in grain size i.e., reduction of grain boundaries and the unfavorable formation of oxygen vacancies. When annealing in air, the formation of oxygen vacancies is suppressed, resulting in up to 1.5 fold enhancement of the photocurrent and an order of magnitude increase of the charge carrier mobility. However, vanadium leaves the BiVO4 lattice above 500 C, which leads to a decrease in carrier lifetime and photocurrent. This vanadium loss can be avoided by supplying excess vanadium in the gas phase during annealing. This leads to enhanced charge carrier mobility and lifetime, resulting in improved photocurrents. Overall, this strategy offers a general approach to prevent unfavorable changes of cation stoichiometry during high temperature treatment of complex metal oxide photoelectrode

Population projections of Pacific sardine driven by ocean warming and changing food availability in the California Current

Small pelagic fish are important marine ecosystem components and highly variable fisheries resources. In the California Current upwelling system, Pacific sardine (Sardinops sagax) has supported important fisheries in the past, but contrary to expectations, remains at low biomass despite recent warm ocean conditions. We developed a data-driven, process-based population model that reproduces fluctuations of the US Pacific sardine population based on ocean temperature, early life stage and adult food, and upwelling strength. The lack of sardine recovery after 2014 can be explained by reduced food availability. Ensemble projections for the 21st century driven by downscaled ocean-biogeochemical simulations under three Earth system models (ESMs) show a likely recovery to early 2000s sardine abundance and catch by mid-century, due to increased recruitment. Ecological process uncertainty (ensemble configuration range) is of the same magnitude as uncertainty among ESM projections, and uncertainty related to the thermal optimum of early life stages dominates after 2070. Even for a fish species presumably favoured by warmer conditions, future climate projections entail risks of stock declines in food-limited years and when passing unknown thermal optima. Quantification of combined environmental driver impacts and sources of uncertainty to projections under novel conditions open new pathways for environment-responsive fisheries management strategies

Marine Heatwaves and Climate‐Driven Warming Impact Availability of Sardine Subpopulations to Northeast Pacific Fishing Ports

ABSTRACT: Changing ocean conditions are leading to spatial redistribution of many marine species, including those that support fisheries. A combination of gradual climate trends and shorter‐lived extreme events, such as marine heatwaves, can change the availability of species or stocks to fishing ports, impacting fishing communities and challenging fisheries management frameworks. Pacific sardine (Sardinops sagax) in the California Current System are currently considered as two subpopulations for management purposes. They are separated from each other using oceanographic conditions, based on the assumption that each subpopulation is associated with different habitats and geographic areas. However, as climate change and marine heatwaves lead to increasingly novel environmental conditions in the region, habitat‐based assignments may become impractical or unrealistic. In this study, we use generalized additive models to define sea surface temperature and surface chlorophyll conditions associated with the occurrence of multiple sardine life stages in fishery‐independent surveys conducted in the California Current System. We then show how the spatial distribution of habitats across life stages and putative subpopulations may be influenced by both gradual climate change and marine heatwaves. Our results highlight the potential impacts of changing ocean conditions near major sardine landing ports. During recent marine heatwaves, habitat associated with the northern subpopulation became less available to southern California Current ports, and this trend is projected to continue through the end of the 21st century. Future spatial shifts in sardine habitat may increasingly challenge the practicality of habitat‐based subpopulation separation and introduce more uncertainty into management frameworks

Application of a data-assimilative regional ocean modeling system for assessing California Current System ocean conditions, krill, and juvenile rockfish interannual variability

Abstract To be robust and informative, marine ecosystem models and assessments require parameterized biophysical relationships that rely on realistic water column characteristics at appropriate spatial and temporal scales. We examine how hydrographic properties off California from 1990 through 2010 during late winter and spring correspond to krill and juvenile rockfish (Sebastes spp.) abundances. We evaluated coherence among temperature, salinity, depth of 26.0 potential density isopycnal, and stratification strength at regionally and monthly time scales derived from shipboard and mooring observations, and a data-assimilative Regional Ocean Model System reanalysis. The reanalysis captures spatiotemporal physical variability of coastal ocean conditions in winter and spring months and elucidates mechanisms connecting the spatial and temporal upwelling and transport dynamics on observed krill and rockfish abundances in spring. This provides evidence for a mechanistic connection between the phenology of upwelling in the California Current System and seasonal development of the shelf ecosystem

Cost-effectiveness analysis of stand-alone or combined non-invasive imaging tests for the diagnosis of stable coronary artery disease: results from the EVINCI study

Aim: This study aimed at evaluating the cost-effectiveness of different non-invasive imaging-guided strategies for the diagnosis of obstructive coronary artery disease (CAD) in a European population of patients from the Evaluation of Integrated Cardiac Imaging in Ischemic Heart Disease (EVINCI) study. Methods and results: Cost-effectiveness analysis was performed in 350 patients (209 males, mean age 59 ± 9 years) with symptoms of suspected stable CAD undergoing computed tomography coronary angiography (CTCA) and at least one cardiac imaging stress-test prior to invasive coronary angiography (ICA) and in whom imaging exams were analysed at dedicated core laboratories. Stand-alone stress-tests or combined non-invasive strategies, when the first exam was uncertain, were compared. The diagnostic end-point was obstructive CAD defined as > 50% stenosis at quantitative ICA in the left main or at least one major coronary vessel. Effectiveness was defined as the percentage of correct diagnosis (cd) and costs were calculated using country-specific reimbursements. Incremental cost-effectiveness ratios (ICERs) were obtained using per-patient data and considering “no-imaging” as reference. The overall prevalence of obstructive CAD was 28%. Strategies combining CTCA followed by stress ECHO, SPECT, PET, or stress CMR followed by CTCA, were all cost-effective. ICERs values indicated cost saving from − 969€/cd for CMR-CTCA to − 1490€/cd for CTCA-PET, − 3092€/cd for CTCA-SPECT and − 3776€/cd for CTCA-ECHO. Similarly when considering early revascularization as effectiveness measure. Conclusion: In patients with suspected stable CAD and low prevalence of disease, combined non-invasive strategies with CTCA and stress-imaging are cost-effective as gatekeepers to ICA and to select candidates for early revascularization

Ca2+-induced changes in energy metabolism and viability of melanoma cells

Cancer cells are characterized by a high rate of glycolysis, which is their primary energy source. We show here that a rise in intracellular-free calcium ion (Ca2+), induced by Ca2+-ionophore A23187, exerted a deleterious effect on glycolysis and viability of B16 melanoma cells. Ca2+-ionophore caused a dose-dependent detachment of phosphofructokinase (EC 2.7.1.11), one of the key enzymes of glycolysis, from cytoskeleton. It also induced a decrease in the levels of glucose 1,6-bisphosphate and fructose 1,6-bisphosphate, the two stimulatory signal molecules of glycolysis. All these changes occurred at lower concentrations of the drug than those required to induce a reduction in viability of melanoma cells. We also found that low concentrations of Ca2+-ionophore induced an increase in adenosine 5′-triphosphate (ATP), which most probably resulted from the increase in mitochondrial-bound hexokinase, which reflects a defence mechanism. This mechanism can no longer operate at high concentrations of the Ca2+-ionophore, which causes a decrease in mitochondrial and cytosolic hexokinase, leading to a drastic fall in ATP and melanoma cell death. The present results suggest that drugs which are capable of inducing accumulation of intracellular-free Ca2+ in melanoma cells would cause a reduction in energy-producing systems, leading to melanoma cell death. © 1999 Cancer Research Campaig