The impact of ocean warming and acidification on the behaviour of two co-occurring Gadid species, Boreogadus saida and Gadus morhua from Svalbard

Ocean acidification induces strong behavioural alterations in marine fish as a conse- quence of acid−base regulatory processes in response to increasing environmental CO2 partial pressure. While these changes have been investigated in tropical and temperate fish species, nothing is known about behavioural effects on polar species. In particular, fishes of the Arctic Ocean will experience much greater acidification and warming than temperate or tropical species. Also, possible interactions of ocean warming and acidification are still understudied. Here we analysed the combined effects of warming and acidification on behavioural patterns of 2 fish species co-occurring around Svalbard, viz. polar cod Boreogadus saida and Atlantic cod Gadus morhua. We found a significant temperature effect on the spontaneous activity of B. saida, but not of G. morhua. Environmental CO2 did not significantly influence activity of either species. In con- trast, behavioural laterality of B. saida was affected by CO2 but not by temperature. Behavioural laterality of G. morhua was not affected by temperature or CO2; however, in this species, a possi- ble temperature dependency of CO2 effects on relative laterality may have been missed due to sample size restrictions. This study indicates that fish in polar ecosystems may undergo some, albeit less intense, behavioural disturbances under ocean acidification and in combination with ocean warming than observed in tropical species. It further accentuates species-specific differ- ences in vulnerability

Local and systemic biomarkers in gingival crevicular fluid increase odds of periodontitis

AimTo determine the independent and combined associations of interleukin-1beta (IL-1beta) and C-reactive protein (CRP) in gingival crevicular fluid (GCF) on periodontitis case status in the Australian population.Materials and methodsGCF was collected from 939 subjects selected from the 2004-2006 Australian National Survey of Adult Oral Health: 430 cases had examiner-diagnosed periodontitis, and 509 controls did not. IL-1beta and CRP in GCF were detected by enzyme-linked immunosorbent assays. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated in bivariate and stratified analysis and fully adjusted ORs were estimated using multivariate logistic regression.ResultsGreater odds of having periodontitis was associated with higher amounts of IL-1beta (OR=2.4, 95% CI=1.7-3.4 for highest tertile of IL-1beta relative to lowest tertile) and CRP (OR=1.9, 95% CI=1.5-2.5 for detectable CRP relative to undetectable CRP). In stratified analysis, there was no significant interaction between biomarkers (p=0.68). In the multivariate analyses that controlled for conventional periodontal risk factors, these relationships remained (IL-1beta OR=1.8, 95% CI=1.1-2.6; CRP OR=1.7, 95% CI=1.3-2.3).ConclusionsElevated odds of clinical periodontitis was associated independently with each biomarker. This suggests that people with elevated biomarkers indicative of either local (IL-1beta) or systemic (CRP) inflammation are more likely to suffer from periodontal disease.Tracy R. Fitzsimmons, Anne E. Sanders, P. Mark Bartold and Gary D. Slad

A hybrid finite element and surrogate modelling approach for simulation and monitoring supported TBM steering

The paper proposes a novel computational method for real-time simulation and monitoring-based predictions during the construction of machine-driven tunnels to support decisions concerning the steering of tunnel boring machines (TBMs). The proposed technique combines the capacity of a process-oriented 3D simulation model for mechanized tunnelling to accurately describe the complex geological and mechanical interactions of the tunnelling process with the computational efficiency of surrogate (or meta) models based on artificial neural networks. The process-oriented 3D simulation model with updated model parameters based on acquired monitoring data during the advancement process is used in combination with surrogate models to determine optimal tunnel machine-related parameters such that tunnelling-induced settlements are kept below a tolerated level within the forthcoming process steps. The performance of the proposed strategy is applied to the Wehrhahn-line metro project in Düsseldorf, Germany and compared with a recently developed approach for real-time steering of TBMs, in which only surrogate models are used

Aortic flow is abnormal in HFpEF

Aims: Turbulent aortic flow makes the cardiovascular system less effective. It remains unknown if patients with heart failure with preserved ejection fraction (HFpEF) have disturbed aortic flow. This study sought to investigate advanced markers of aortic flow disturbances in HFpEF. Methods: This case-controlled observational study used four-dimensional flow cardiovascular magnetic resonance derived, two-dimensional phase-contrast reformatted plane data at an orthogonal plane just above the sino-tubular junction. We recruited 10 young healthy controls (HCs), 10 old HCs and 23 patients with HFpEF. We analysed average systolic aortic flow displacement (FDsavg), systolic flow reversal ratio (sFRR) and pulse wave velocity (PWV). In a sub-group analysis, we compared old HCs versus age-gender-matched HFpEF (N=10). Results: Differences were significant in mean age (P 17.7% achieved 74% sensitivity, 70% specificity for differentiating them. sFRR was notably higher in HFpEF (11±10% vs 7±6%, P 7.3% yielded 78% sensitivity, 70% specificity in differentiating these groups. In sub-group analysis, FDsavg remained distinctly elevated in HFpEF (22.4±9.7% vs 16±4.9%, P=0.029). FDsavg of >16% showed 100% sensitivity and 70% specificity (P=0.01). Similarly, sFRR remained significantly higher in HFpEF (11.3±9.5% vs 6.6±6.4%, P=0.007). A sFRR of >7.2% showed 100% sensitivity and 60% specificity (P<0.001). Conclusion: Aortic flow haemodynamics namely FDsavg and sFRR are significantly affected in ageing and HFpEF patients

Export and lateral advection of organic matter within the biological carbon pump

The biological carbon pump (BCP) exports organic carbon from the surface to the deep ocean through which it drives the oceanic carbon storage of atmospheric CO2. The majority of this exported carbon is mediated by sinking marine particles, which are mostly formed by primary producers i.e. phytoplankton, and detrital material including dead zoo- and phytoplankton as well as fecal pellets. The efficiency at which these marine particles are exported is largely dependent on the interplay between their degradation and the duration the particles settle through the water column. Particle and aggregate degradation is largely driven by attached microbes and zooplankton grazing, which is most prominent in the upper few hundred meters of the water column. Settling velocities of particles or aggregates are largely determined by their density and thus composition. Therefore, fast settling aggregates or particles sink more rapidly through the upper water column, which increases the carbon export efficiency. The incorporation of ballasting components, such as sediments or minerals, during particle aggregation may increase the size-specific settling velocities of the aggregates and are thus an important process for carbon export via the biological pump. The manuscripts within this dissertation focus on the impact of aggregate morphology and ballasting on settling velocities and how carbon export is mediated by slow versus fast settling aggregates. We investigated (1) the horizontal relocation of slow vs. fast settling aggregates in form of subsurface particle clouds, (2) aggregate ballasting through the incorporation of minerals which are released by melting sea-ice and (3) the role of the aggregate microstructure on settling

Krill and salp faecal pellets contribute equally to the carbon flux at the Antarctic Peninsula

This study was part of the project “Population shift and ecosystem response – krill vs. salps” funded by the Lower Saxony Ministry of Science and Culture (MWK) lead by B.M. M.H.I., C.M.F., C.K. and S.S. were supported by the HGF Young Investigator Group SeaPump “Seasonal and regional food web interactions with the biological pump”, VH-NG-1000. CMF was additionally supported by the AWI Strategy Fund project EcoPump. MHI was additionally supported by the DFG Research Center of Excellence “The Ocean Floor – Earth’s Uncharted Interface”: EX-2077-390741603.Krill and salps are important for carbon flux in the Southern Ocean, but the extent of their contribution and the consequences of shifts in dominance from krill to salps remain unclear. We present a direct comparison of the contribution of krill and salp faecal pellets (FP) to vertical carbon flux at the Antarctic Peninsula using a combination of sediment traps, FP production, carbon content, microbial degradation, and krill and salp abundances. Salps produce 4-fold more FP carbon than krill, but the FP from both species contribute equally to the carbon flux at 300 m, accounting for 75% of total carbon. Krill FP are exported to 72% to 300 m, while 80% of salp FP are retained in the mixed layer due to fragmentation. Thus, declining krill abundances could lead to decreased carbon flux, indicating that the Antarctic Peninsula could become a less efficient carbon sink for anthropogenic CO2 in future.Publisher PDFPeer reviewe