Effects of ocean acidification on invertebrate settlement at volcanic CO<inf>2</inf> vents

We present the first study of the effects of ocean acidification on settlement of benthic invertebrates and microfauna. Artificial collectors were placed for 1 month along pH gradients at CO2 vents off Ischia (Tyrrhenian Sea, Italy). Seventy-nine taxa were identified from six main taxonomic groups (foraminiferans, nematodes, polychaetes, molluscs, crustaceans and chaetognaths). Calcareous foraminiferans, serpulid polychaetes, gastropods and bivalves showed highly significant reductions in recruitment to the collectors as pCO2 rose from normal (336-341 ppm, pH 8.09-8.15) to high levels (886-5,148 ppm) causing acidified conditions near the vents (pH 7.08-7.79). Only the syllid polychaete Syllis prolifera had higher abundances at the most acidified station, although a wide range of polychaetes and small crustaceans was able to settle and survive under these conditions. A few taxa (Amphiglena mediterranea, Leptochelia dubia, Caprella acanthifera) were particularly abundant at stations acidified by intermediate amounts of CO2 (pH 7. 41-7.99). These results show that increased levels of CO2 can profoundly affect the settlement of a wide range of benthic organisms. © 2010 Springer-Verlag

Mobility, proprioception, strength and FMS as predictors of injury in professional footballers

Background The premise of this study was to investigate if anthropometric variables such as mobility, proprioception, strength and modified Functional Movement Screen (mFMS) could be used as primary indicators of injury risk in an English Championship division football team. This study focused on moderate injuries occurring in the lower extremities, during the 2014/2015 competitive season. Methods To differentiate between minor, moderate and severe injuries, this study classified moderate injuries as an injury with an average injury severity of 2–28 days. This study is composed of 4 individual investigations. Each variable was assessed against 2 groups: injured (n=6) and non-injured (n=10). The 2 groups were compiled from the first team, with the criteria that each participant of this study required: full preseason assessment and injury history for the time period, 1 July 2014 to 19 March 2015. A Mann-Whitney U test (0.05% significance) was applied to statistically analyse if each variable showed any variation across the 2 groups. Effect size was estimated with Cliff's d. Results Strength asymmetry displayed significant difference (p=0.007), mobility, proprioception and mFMS did not (p=0.263, p=0.792 and p=0.181, respectively). Mean scores for mobility, proprioception, strength asymmetry and mFMS for injured versus non-injured players (effect size) were: 40.00 vs 38.00 (0.37), 10.33 vs 10.20 (0.10), 61.13 vs 30.40 (0.80) and 7.33 vs 8.90 (−0.4), respectively. Conclusions This study found no relationship between mobility/proprioception and injury risk; however, strength asymmetry was statistically significant in predicting injury and mFMS exhibited enough positive difference for recommendation of further investigation

Salvation Abroad: Macedonian Migration to North America and the Making of Modern Macedonia, 1870-1970

This dissertation explores the establishment of Macedonian diaspora communities in North America, and the concurrent development of Macedonian national identity, between 1870 and 1970. Taking a transnational approach to cultural history, it ultimately finds a reciprocal relationship between Macedonian migration and identity by focusing on key nationalist leaders and organizations, as well as the crucial points of transformation in the evolution of Macedonian national identity. By blurring the boundary between Canada and the United States - as did many migrants from Macedonia who saw the two countries as "Upper" and "Lower" America - this study emphasizes migration rather than settlement in order to unveil nationalism's religious, cultural and political components. The dissertation, therefore, is grounded not in the cement of a single national narrative, but in the cultural products that result from passages - physical, spiritual, and social - among nations. As the nineteenth century ended, a climate of deprivation and violence compelled tens of thousands of men from the Macedonian region to depart their troubled corner of the Balkans and find economic salvation abroad. Like their fellow villagers, most of the migrants considered themselves to be geographically Macedonian but culturally Bulgarian. Almost none identified with a nationality in the modern sense. This study argues, however, that more than simply fulfilling an economic mission abroad, the migrant men, and later their families, capitalized on the freedoms North America offered to forge a broader "salvation" that fundamentally changed their national and ethnic worldview. Put another way, migration catalyzed a process in which the migrants became, simply, "Macedonians." Far from leaving behind the political and cultural battles of their homeland, the migrant communities formed political, cultural, and religious organizations that sought to influence the policies of both their host and home countries. But defining the new Macedonian nation proved a contentious issue. As the migrant communities cleaved into left- and right-leaning factions during the middle and latter years of the twentieth century, the nature of Macedonian identity, which, I argue, was intimately connected to notions of Macedonian cultural history, became a fiercely contested subject, and remains so today

Abiotic conditions in cephalopod (Sepia officinalis) eggs: embryonic development at low pH and high pCO2

Low pO(2) values have been measured in the perivitelline fluids (PVF) of marine animal eggs on several occasions, especially towards the end of development, when embryonic oxygen consumption is at its peak and the egg case acts as a massive barrier to diffusion. Several authors have therefore suggested that oxygen availability is the key factor leading to hatching. However, there have been no measurements of PVF pCO(2) so far. This is surprising, as elevated pCO(2) could also constitute a major abiotic stressor for the developing embryo. As a first attempt to fill this gap in knowledge, we measured pO(2), pCO(2) and pH in the PVF of late cephalopod (Sepia officinalis) eggs. We found linear relationships between embryo wet mass and pO(2), pCO(2) and pH. pO(2) declined from > 12 kPa to less than 5 kPa, while pCO(2) increased from 0.13 to 0.41 kPa. In the absence of active accumulation of bicarbonate in the PVF, pH decreased from 7.7 to 7.2. Our study supports the idea that oxygen becomes limiting in cephalopod eggs towards the end of development; however, pCO(2) and pH shift to levels that have caused significant physiological disturbances in other marine ectothermic animals. Future research needs to address the physiological adaptations that enable the embryo to cope with the adverse abiotic conditions in their egg environment

Lessons from two high CO2 worlds - future oceans and intensive aquaculture

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Exponentially rising CO2 (currently ~400 μatm) is driving climate change and causing acidification of both marine and freshwater environments. Physiologists have long known that CO2 directly affects acid-base and ion regulation, respiratory function and aerobic performance in aquatic animals. More recently, many studies have demonstrated that elevated CO2 projected for end of this century (e.g. 800-1000 μatm) can also impact physiology, and have substantial effects on behaviours linked to sensory stimuli (smell, hearing and vision) both having negative implications for fitness and survival. In contrast, the aquaculture industry was farming aquatic animals at CO2 levels that far exceed end-of-century climate change projections (sometimes >10 000 μatm) long before the term 'ocean acidification' was coined, with limited detrimental effects reported. It is therefore vital to understand the reasons behind this apparent discrepancy. Potential explanations include 1) the use of 'control' CO2 levels in aquaculture studies that go beyond 2100 projections in an ocean acidification context; 2) the relatively benign environment in aquaculture (abundant food, disease protection, absence of predators) compared to the wild; 3) aquaculture species having been chosen due to their natural tolerance to the intensive conditions, including CO2 levels; or 4) the breeding of species within intensive aquaculture having further selected traits that confer tolerance to elevated CO2 . We highlight this issue and outline the insights that climate change and aquaculture science can offer for both marine and freshwater settings. Integrating these two fields will stimulate discussion on the direction of future cross-disciplinary research. In doing so, this article aimed to optimize future research efforts and elucidate effective mitigation strategies for managing the negative impacts of elevated CO2 on future aquatic ecosystems and the sustainability of fish and shellfish aquaculture.The authors wish to acknowledge the funding that has contributed to ideas within this manuscript. This includes a United Kingdom Ocean Acidification Research Program (UKOARP) Project (NE/H01750X/1 to R.W.W.) cofunded by the Natural Environment Research Council (NERC), the Department for Environment, Food and Rural Affairs (Defra) and the Department of Energy and Climate Change (DECC), together with various BBSRC-funded projects (BB/J00913X/1, BB/N013344/1 and BB/M017583/1 to R.W.W.)

Food availability outweighs ocean acidification effects in juvenileMytilus edulis: laboratory and field experiments

Ocean acidification is expected to decrease calcification rates of bivalves. Nevertheless in many coastal areas high pCO2 variability is encountered already today. Kiel Fjord (Western Baltic Sea) is a brackish (12-20 g kg-1) and CO2 enriched habitat, but the blue mussel Mytilus edulis dominates the benthic community. In a coupled field and laboratory study we examined the annual pCO2 variability in this habitat and the combined effects of elevated pCO2 and food availability on juvenile M. edulis growth and calcification. In the laboratory experiment, mussel growth and calcification were found to chiefly depend on food supply, with only minor impacts of pCO2 up to 3350 μatm. Kiel Fjord was characterized by strong seasonal pCO2 variability. During summer, maximal pCO2 values of 2500 μatm were observed at the surface and >3000 μatm at the bottom. However, the field growth experiment revealed seven times higher growth and calcification rates of M. edulis at a high pCO2 inner fjord field station (mean pCO2 ca. 1000 μatm) in comparison to a low pCO2 outer fjord station (ca. 600 μatm). In addition, mussels were able to outcompete the barnacle Amphibalanus improvisus at the high pCO2 site. High mussel productivity at the inner fjord site was enabled by higher particulate organic carbon concentrations. Kiel Fjord is highly impacted by eutrophication, which causes bottom water hypoxia and consequently high seawater pCO2. At the same time, elevated nutrient concentrations increase the energy availability for filter feeding organisms such as mussels. Thus M. edulis can dominate over a seemingly more acidification resistant species such as A. improvisus. We conclude that benthic stages of M. edulis tolerate high ambient pCO2 when food supply is abundant and that important habitat characteristics such as species interactions and energy availability need to be considered to predict species vulnerability to ocean acidification

Juvenile king scallop, Pecten maximus, is potentially tolerant to low levels of ocean acidification when food is unrestricted.

The decline in ocean water pH and changes in carbonate saturation states through anthropogenically mediated increases in atmospheric CO2 levels may pose a hazard to marine organisms. This may be particularly acute for those species reliant on calcareous structures like shells and exoskeletons. This is of particular concern in the case of valuable commercially exploited species such as the king scallop, Pecten maximus. In this study we investigated the effects on oxygen consumption, clearance rates and cellular turnover in juvenile P. maximus following 3 months laboratory exposure to four pCO2 treatments (290, 380, 750 and 1140 µatm). None of the exposure levels were found to have significant effect on the clearance rates, respiration rates, condition index or cellular turnover (RNA: DNA) of individuals. While it is clear that some life stages of marine bivalves appear susceptible to future levels of ocean acidification, particularly under food limiting conditions, the results from this study suggest that where food is in abundance, bivalves like juvenile P. maximus may display a tolerance to limited changes in seawater chemistry

Effect of the Independent Acid Base Variables on Anion Gap Variation in Cardiac Surgical Patients: A Stewart-Figge Approach

Purpose. To determine the effect of each of independent acid base variables on the anion gap (AG) value in cardiac surgical patients. Methods. This retrospective study involved 128 cardiac surgical patients admitted for postoperative care. The variation of AG (AGvar) between the day of admission and the first postoperative day was correlated via a multiple linear regression model with the respective variations of the independent acid base variables, that is, apparent strong ion difference (SIDa), strong ion gap (SIG), carbon dioxide (PCO2), and albumin and phosphate concentrations. Results. The variations of all the above variables contributed significantly to the prediction of AGvar (adjusted R2=0.9999, F=201890.24, and P<0.001). According to the standardized coefficients (β),  SIGvar (β = 0.948, P<0.001), [Albumin]var (β = 0.260, P<0.001), and [Phosphate]var (β = 0.191, P<0.001) were the major determinants of AGvar with lesser contributions from SIDa, var (β = 0.071, P<0.001) and PCO2, var (β = −0.067, P<0.001). Conclusions. All the independent acid base variables contribute to the prediction of the AG value. However, albumin and phosphate and SIG variations seem to be the most important predictors, while AG appears to be rather stable with changes in PCO2 and SIDa

Optical coherence tomography angiography findings in pigmented paravenous chorioretinal atrophy

Purpose:To analyze the retino-choroidal vascular characteristics of patients affected by pigmented paravenous chorio-retinal atrophy by means of optical coherence tomography (OCT) angiography.Methods:This study was designed as an observational, cross-sectional case series. Multimodal imaging included fundus autofluorescence, structural OCT, and OCT angiography. The quantitative OCT angiography analyses included the calculation of the vessel density and choriocapillaris porosity.Results:Overall, 12 patients (24 eyes) affected by pigmented paravenous chorio-retinal atrophy were recruited. Structural OCT of the areas involved by pigmented paravenous chorio-retinal atrophy as visualized on the fundus autofluorescence showed a complete ellipsoid zone and external limiting membrane absence, with thinning of ganglion cell complex, outer nuclear layer, and outer plexiform layer, but associated with the optical partial preservation of the retinal pigment epithelium. Optical coherence tomography angiography quantitative assessment of the retinal regions affected by PPRCA, as visualized by fundus autofluorescence, was characterized by normal vessel density at the level of superficial capillary plexus but significantly altered vessel density of deep capillary plexus and choriocapillaris, with higher choriocapillaris porosity. The presence of macular atrophy was significantly correlated with worse deep capillary plexus and choriocapillaris vessel density values. Furthermore, a statistically significant correlation between the fundus autofluorescence patterns and the retinal vascular status was found.Conclusion:Optical coherence tomography angiography quantitative analyses in pigmented paravenous chorio-retinal atrophy demonstrate a specific impairment at the level of the deep capillary plexus, which could in turn bring about a thinning of ganglion cell complex and outer nuclear layer. The alterations at the level of the choriocapillaris and the choroid, in general, could then represent a secondary effect

Metabolic remodeling caused by heat-hardening in the Mediterranean mussel Mytilus galloprovincialis

Organisms can modify and increase their thermal tolerance faster and more efficiently after a brief exposure to sublethal thermal stress. This response is called ‘heat hardening’ as it leads to the generation of phenotypes with increased heat tolerance. The aim of this study was to investigate the impact of heat hardening on the metabolomic profile of Mytilus galloprovincialis in order to identify the associated adjustments of biochemical pathways that might benefit the mussels’ thermal tolerance. Thus, mussels were exposed sequentially to two different phases (heat hardening and acclimation phases). To gain further insight into the possible mechanisms underlying the metabolic response of the heat-hardened M. galloprovincialis, metabolomics analysis was complemented by the estimation of mRNA expression of phosphoenolpyruvate carboxykinase (PEPCK), pyruvate kinase (PK) and alternative oxidase (AOX) implicated in the metabolic pathways of gluconeogenesis, glycolysis and redox homeostasis, respectively. Heat-hardened mussels showed evidence of higher activity of the tricarboxylic acid (TCA) cycle and diversification of upregulated metabolic pathways, possibly as a mechanism to increase ATP production and extend survival under heat stress. Moreover, formate and taurine accumulation provide an antioxidant and cytoprotective role in mussels during hypoxia and thermal stress. Overall, the metabolic responses in non-heat-hardened and heat-hardened mussels underline the upper thermal limits of M. galloprovincialis, set at 26°C, and are in accordance with the OCLTT concept. The ability of heat-hardened mussels to undergo a rapid gain and slow loss of heat tolerance may be an advantageous strategy for coping with intermittent and often extreme temperatures