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Studies that address fish welfare before slaughter have concluded that many of the traditional systems used to stun fish including CO 2 narcosis are unacceptable as they cause avoidable stress before death. One system recommended as a better alternative is electrical stunning, however, the welfare aspects of this method are not yet fully understood. To assess welfare in aquaculture both behavioural and physiological measurements have been used, but few studies have examined the relationship between these variables. In an on-site study aversive behaviours and several physiological stress indicators, including plasma levels of cortisol and ions as well as blood physiological variables, were compared in Arctic char (Salvelinus alpinus) stunned with CO 2 or electricity. Exposure to water saturated with CO 2 triggered aversive struggling and escape responses for several minutes before immobilization, whereas in fish exposed to an electric current immobilization was close to instant. On average, it took 5 min for the fish to recover from electrical stunning, whereas fish stunned with CO 2 did not recover. Despite this, the electrically stunned fish had more than double the plasma levels of cortisol compared with fish stunned with CO 2. This result is surprising considering that the behavioural reactions were much more pronounced following CO 2 exposure. These contradictory results are discussed with regard to animal welfare and stress physiological responses. The present results emphasise the importance of using an integrative and interdisciplinary approach and to include both behavioural and physiological stress indicators in order to make accurate welfare assessments of fish in aquaculture. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is used for immobilisation of Arctic char (Salvelinus alpinus) prior to slaughter at Swedish aquaculture facilities, and fish are routinely exposed to hypothermia in ice water during transport. Yet, information on stress physiological responses to CO2, temperature extremes and their potential interacting effects is scarce for this cold-water species. Here, blood pressure, heart and ventilation rates and plasma variables including ions, haematocrit, glucose and cortisol were measured in cannulated char during exposure to hypothermia (i.e. a rapid temperature drop from 10°C to 0.25°C); as well as to water nearly saturated with CO2 at 10°C and 0.25°C to test the hypothesis that hypothermia alleviates stress responses during CO2 exposure. While all fish maintained equilibrium during the 30min hypothermic challenge, blood pressure, heart and ventilation rates decreased and plasma cortisol increased moderately. CO2 exposure at 10 and 0.25°C resulted in aversive behavioural reactions before equilibrium was irrecoverably lost after 184±14 and 191±9s, respectively. The physiological responses to CO2 exposure were largely similar at both temperatures with elevated cortisol levels, reduced heart and ventilation rates and hypotension; although reductions in ventilation amplitude and arterial pulse pressure were significantly more pronounced at 0.25°C. It is concluded that hypothermia alone is a relatively mild stressor in this species, while CO2 exposure elicits pronounced physiological and behavioural stress responses that are not alleviated by hypothermia. [ABSTRACT FROM AUTHOR]

Abstract: One of the most crucial parameters for successful grouting is to ensure that the grout can penetrate the necessary apertures. For the most commonly used grout, cementitious grout, the available methods for determining the ability to penetrate apertures involves several measurements with different meshes or similar, which need to be evaluated. However, during the grouting process in the field there is rarely any time for evaluation and the most commonly used field method today stipulates a mesh width through which a certain volume need to pass. This implies that only an indirect measurement of the penetrability is performed. In order to perform direct and fast field measurements of the penetrability, a new, robust measuring device has been developed at Chalmers University of Technology in Gothenburg, Sweden. The device is named PenetraCone and the measuring part consists of a gap that is formed between two conical cylinders. The penetrability characteristics are measured by decreasing this gap as grout flows through. The gap is measured using a dial indicator gauge. Initial tests with the PenetraCone show that two characteristic gaps or widths can be evaluated. The width as the grout flow goes from continuous flow to dripping is termed bfilter and when the flow stops completely it is termed bstop . The parameter bfilter is related to the commencement of clogging or filtration of the cementitious grout. This means that for apertures larger than bfilter the cement passes unrestricted but for narrower apertures filtration will commence. This filtration process will occur in apertures down to bstop , which indicates the smallest aperture that the cement can pass through and for apertures below bstop the cement will not penetrate at all. The device is easy to use and the tests show that consistent values are obtained. The accuracy seems good enough for use as a control of the penetrability of cementitious grouts in the field. For use in production, the PenetraCone should be placed on the grouting rig, after the mixer, so that direct measurements can be performed on the grout that will actually be used for grouting. By relating the measured parameters to the penetrability requirements, quick decisions regarding the quality of the grout can be made directly on the grouting rig. [Copyright &y& Elsevier]

Abstract: Cementitious grouts are the most commonly used grouting material in the world. The general concept of grouting is to propagate the grout in a sufficiently large volume in the grouted medium and hence to have a controlled penetration. This study has been performed in order to determine and test the different mechanisms that result in stoppage of the penetration of cementitious grouts. This is performed as sand column tests in a laboratory study, coupled with grouting in the field. The result shows that three different stop mechanisms can be identified depending on the ratio between the grain size of the grout and the available opening. At an opening up to three times the size of the largest grout grains, penetration does not occur due to clogging of the grains. For an opening larger than five times the largest grain the penetration is unrestricted and stoppage occurs due to equilibrium between the driving and resistance forces. Between these ratios, a transition area exists where the water content determines the penetrability and the stoppage is governed by a filtration process for the grout grains. This implies that grouting with higher water-to-cement ratios results in a larger penetration area and hence by applying the mixture-thickening method during grouting an increased sealing efficiency can be obtained. [Copyright &y& Elsevier]

Summary: Background: Striving for improved adherence and asthma control is of vital concern in today''s asthma management. Several influential factors have been identified, but the importance of personality traits has been insufficiently explored. The aim was first to determine whether personality traits in young adult asthmatics are related to asthma control and health-related quality of life (HRQL), and second to examine the influences of personality traits on adherence to regular asthma medication treatment. Methods: Young adult asthmatics, 22 years of age (n =268) completed questionnaires. Statistical analyses were performed. Results: The personality traits Negative Affectivity and Impulsivity correlated negatively with asthma control, whereas in women Hedonic Capacity correlated positively with asthma control. Negative Affectivity, Impulsivity, Hedonic Capacity, Alexithymia and asthma control predicted the mental dimension of HRQL. Asthma control and physical activity predicted the physical dimension of HRQL. Among respondents with regular asthma medication (n =109), Impulsivity correlated negatively with adherence. In men, Antagonism and Alexithymia were associated with low adherence. Additionally, Alexithymia, Hedonic Capacity and Negative Affectivity showed non-linear relationships with adherence, meaning that initially increased scores on these personality traits scales were associated with increased adherence but higher scores did not increase adherence. Respondents who were prescribed a single inhaler combining ICS and LABA reported higher adherence than those with monotherapies. Conclusion: These data suggest that personality can influence how asthma patients adhere to asthma medication treatment, and report their control and HRQL. Tools determining personality traits may be useful in the future in individualizing management of asthma patients. [Copyright &y& Elsevier]

Abstract: This introductory study on mechanical properties aims to characterize silica sol and to improve knowledge of the suitability of silica sol as grout. Silica sol is a non-cementitious grout that consists of spherical particles of amorphous silica, with a diameter of 5–100nm. For a testing period of six months, specimens of silica sol were kept at 8°C with three relative humidities: 75%, 95% and 100%. During the test period measurements of the drying shrinkage, compressive strength, modulus of elasticity (Young’s modulus), shear strength and flexural strength were made. The results show that the strength of silica sol continues to increase for a long time and during the test period of six months the strength kept increasing. The increase of strength depends on the humidity to which silica sol is exposed but the humidity also affects the drying shrinkage. A lower humidity results in a faster increase in strength but also a larger shrinkage. [Copyright &y& Elsevier]

Abstract: Hypoxia in fish is generally associated with bradycardia while cardiac output (Q˙) remains unaltered or slightly increased due to a compensatory increase in stroke volume (SV). Rainbow trout (Oncorhynchus mykiss) were subjected to severe (P WO2=7.3±0.2 kPa) or mild (P WO2=11.5±0.2 kPa) hypoxia. Central venous pressure (P ven), dorsal aortic pressure (P da), heart rate (f H) and Q˙, were recorded in vivo. Both levels of hypoxia triggered a significant increase in P ven. Severe hypoxia was associated with bradycardia and unaltered Q˙, whereas mild hypoxia was associated with a small but significant increase in Q˙ and no bradycardia. These findings indicate that an increase in P ven promotes an increase in SV during hypoxia. Since mild hypoxia increased P ven, Q˙ and SV without bradycardia or reduced systemic resistance (R sys), we hypothesize that an active increase in venous tone serving to mobilize blood to the central venous compartment in order to increase cardiac preload and consequently SV, is an important cardiovascular trait associated with hypoxia. Pharmacological pre-treatment with prazosin (1 mg kg-1) did not conclusively reveal the underlying mechanisms to the observed changes in P ven. This study discusses the influence of venous pooling, reduced R sys and altered venous tone on changes in P ven observed during hypoxia. [Copyright &y& Elsevier]

• All patients with ongoing disease activity (relapse or new lesions on MRI) had increased NFL or CXCL13. • The same proportion of patients with relapsing-remitting and progressive MS without ongoing disease activity had increased either NFL or CXCL13 or both biomarkers. • These markers might be more sensitive to disease activity than clinical and MRI measures. • At a later stage of the disease, NFL and CXCL13 could not predict disease activity or disability. Cerebrospinal fluid (CSF) levels of neurofilament light (NFL), a biomarker of axonal damage, and CXCL13, a chemokine involved in B-cell regulation, are both associated with disease activity in multiple sclerosis (MS). To explore the potential of NFL and CXCL13 to detect residual disease activity in patients with no signs of clinical or ongoing radiological activity and to study the clinical relevance of such activity. NFL and CXCL13 concentrations were determined with ELISA in CSF obtained from 90 relapsing-remitting (RR) MS and 47 Progressive (Pr) MS (including primary and secondary PrMS) at baseline and after 12 months of follow-up. The patients were assessed at baseline, before initiating or switching disease modifying therapy (DMT) and again after 12 and 27 months of follow-up. All patients with ongoing disease activity (relapse or contrast-enhancing lesions on MRI) had increased NFL or CXCL13. The proportion of RRMS and PrMS patients without ongoing disease activity with elevation of either NFL or CXCL13 (residual disease activity) was 39% and 50%, respectively, and both were increased in 11% and 16%, respectively. The treatment with DMTs decreased the proportion with residual disease activity in both RRMS and PrMS significantly. We could not show any significant association between residual disease activity and clinical or MRI measures at 12 or 27 months of follow-up. Although most of this real-world study population had been treated with second-line DMTs and achieved clinical and radiological stability, a significant proportion of patients still displayed increased CSF levels of both NFL and CXCL13, indicating residual disease activity. Thus, these markers seemed considerably more sensitive to disease activity than clinical and MRI measures. However, the long-term clinical significance of such activity remains to be determined. [ABSTRACT FROM AUTHOR]

European whitefish (Coregonus lavaretus) is an aquaculture species with the potential for expanded cultivation in the fresh and brackish waters of Northern Europe. Yet, relatively little species-specific information is available regarding the stress responses and associated welfare implications for this species in captivity. We addressed this knowledge gap by using a combination of implantable heart rate bio-loggers and a range of traditional stress indicators (e.g. haematological parameters and plasma concentrations of cortisol, glucose and ions) to comprehensively evaluate the physiological responses of freely swimming whitefish in captivity, as well as when subjected to aquaculture practices and stressors that commonly occur prior to and during slaughter. Whitefish appeared to recover rapidly from surgery, as resting heart rate decreased within 36 h to stabilize at ~25 beats min−1 for the next 18 days when fish were left relatively undisturbed (i.e. personnel were only present when feeding fish). In contrast with previous studies on farmed rainbow trout and Atlantic salmon, whitefish did not exhibit a clear circadian heart rate rhythm, which may be related to species-specific differences in diurnal locomotor activity. Whitefish also appear to have a well-developed capacity for thermal acclimation of heart rate, as daily resting heart rate did not change during the undisturbed period despite an increase in body temperature from ~6.8 to 11.2 °C. Following acute stressors such as crowding and transportation, the physiological response of whitefish typically involved transient elevations in heart rate, plasma cortisol and glucose, and red blood cell swelling, while plasma [K+] decreased. In contrast, the heart rate of whitefish plummeted following the combination of brailing (i.e. to haul in fish with a brail/net) and CO 2 exposure prior to slaughter, while plasma cortisol, glucose and [Ca2+] significantly increased. An unforeseen finding concerns the substantial and long-lasting physiological stress response observed in whitefish when held in close proximity (i.e. within ~10 m) to a rainbow trout net pen, as the mean heart rate of whitefish increased from ~32 to 43 beats min−1 (i.e. an increase of ~34%). This may represent an innate physiological response to the threat of predation, which consequently increases the allostatic load and energetic expenditure of whitefish when farmed alongside salmonids. To conclude, this study highlights the importance of performing long-term, species-specific evaluations of freely swimming fish in real aquaculture settings, and provides a platform for further research aiming to determine the welfare implications of simultaneously farming predatory and prey species in close proximity. • First recordings of heart rate and body temperature in European whitefish. • Documents the thermal acclimation capacity of whitefish. • Crowding and transportation induce transient elevations in heart rate of whitefish. • CO 2 exposure induces a severe stress response resulting in cardiac collapse. • Whitefish exhibit chronic stress response when held captive near rainbow trout. [ABSTRACT FROM AUTHOR]