Supine MRI for regional breast radiotherapy: Imaging axillary lymph nodes before and after sentinel-node biopsy

Regional radiotherapy (RT) is increasingly used in breast cancer treatment. Conventionally, computed tomography (CT) is performed for RT planning. Lymph node (LN) target levels are delineated according to anatomical boundaries. Magnetic resonance imaging (MRI) could enable individual LN delineation. The purpose was to evaluate the applicability of MRI for LN detection in supine treatment position, before and after sentinel-node biopsy (SNB). Twenty-three female breast cancer patients (cTis-3N0M0) underwent 1.5 T MRI, before and after SNB, in addition to CT. Endurance for MRI was monitored. Axillary levels were delineated. LNs were identified and delineated on MRI from before and after SNB, and on CT, and compared by Wilcoxon signed-rank tests. LN locations and LN-based volumes were related to axillary delineations and associated volumes. Although postoperative effects were visible, LN numbers on postoperative MRI (median 26 LNs) were highly reproducible compared to preoperative MRI when adding excised sentinel nodes, and higher than on CT (median 11, p < 0.001). LN-based volumes were considerably smaller than respective axillary levels. Supine MRI of LNs is feasible and reproducible before and after SNB. This may lead to more accurate RT target definition compared to CT, with potentially lower toxicity. With the MRI techniques described here, initiation of novel MRI-guided RT strategies aiming at individual LNs could be possible

Applicability of the valve gape monitor to assist with oysters bed (Ostrea edulis) restoration projects

To monitor flat oyster reef restoration projects in offshore pilots innovative techniques with a focus on remote monitoring are needed. This will reduce the frequency with which offshore pilot study locations have to be visited. The valve gape monitor can potentially be used as an effective method to monitor survival and behaviour of the European flat oyster Ostrea edulis. This is an in situ device that continuously measures the opening and closing of the shell of live bivalves (valves) equipped with sensors. It has been successfully used in combination with other bivalve species. In this study, eight oysters Ostrea edulis from two different regions (Norway and the Netherlands (Grevelingen)) were fitted with valve gape sensors. Valve gape activity was monitored during different experimental conditions (tide simulation and starvation) under controlled conditions to test the applicability of the valve gape monitor to assist with monitoring of O. edulis reef restoration projects. No significant differences in valve gape activity of Norwegian oysters and oysters from the Grevelingen were detected under controlled conditions. Tide simulation did not appear to affect valve gape activity. However, the oysters were responsive to disturbances such as daily maintenance as well as starvation. Size frequency distribution of gape class clearly shows that fed individuals show longer periods of open valves and percentage closure is significantly higher in the starved oysters. Gape width is larger in fed conditions then in starved conditions. In addition, starved oysters open less wide when they open. These results indicate that food availability affects valve gape activity and the valve gape monitor can provide information on the behaviour and stress response of Ostrea edulis. In situ monitoring of flat oyster gape activity should incorporate environmental parameters such as Chl a, temperature, salinity, current speed and oxygen to provide insight into the environmental stressors on and/or the behavioural patterns of flat oysters

Applicability of the gape monitor to study flat oyster (Ostrea edulis) feeding behaviour

Innovative techniques are needed to assess oyster performance in flat oyster reef restoration projects. A valve gape monitor, a device that continuously measures opening and closing of live bivalves, can potentially be used as an effective method to determine survival and behaviour of the European flat oyster Ostrea edulis. The method has been successfully used in combination with a number of bivalve species to investigate valve gape activity in response to environmental factors. In this study, eight O. edulis were equipped with valve gape sensors in order to relate gape to environmental conditions such as food availability. Valve gape activity was monitored under controlled laboratory conditions, with and without food, in a concrete basin in the Oosterschelde and in the field (Voordelta, Dutch North Sea). Under controlled laboratory conditions, oysters clearly responded to changes in food availability. Starved oysters closed their valves significantly longer than oysters that received food, and the relative gape width in fed oysters was larger. In the concrete basin (Oosterschelde), a positive correlation between valve opening and Chlorophyll-a was found. Additionally, valve gape activity and tidal movement appeared to be linked. When exposed to a full tidal cycle (Voordelta), a negative correlation between valve opening and Chlorophyll-a was found. However, there was no correlation between valve gape and current velocity. In autumn, longer periods of inactivity were seen, but when valves opened, the valve gape was larger. These data indicate that valve gape can provide valuable information on behaviour (gape frequency and gape width), but also show that it is not necessarily a good proxy for feeding rate. Nevertheless, these results show that the gape monitor can be used to determine the natural behaviour of flat oysters under field conditions, and that gape opening provides information on behaviour and the stress response of bivalves to environmental conditions

Applicability of the gape monitor to study flat oyster (Ostrea edulis) feeding behaviour

Innovative techniques are needed to assess oyster performance in flat oyster reef restoration projects. A valve gape monitor, a device that continuously measures opening and closing of live bivalves, can potentially be used as an effective method to determine survival and behaviour of the European flat oyster Ostrea edulis. The method has been successfully used in combination with a number of bivalve species to investigate valve gape activity in response to environmental factors. In this study, eight O. edulis were equipped with valve gape sensors in order to relate gape to environmental conditions such as food availability. Valve gape activity was monitored under controlled laboratory conditions, with and without food, in a concrete basin in the Oosterschelde and in the field (Voordelta, Dutch North Sea). Under controlled laboratory conditions, oysters clearly responded to changes in food availability. Starved oysters closed their valves significantly longer than oysters that received food, and the relative gape width in fed oysters were larger. In the concrete basin (Oosterschelde), a positive correlation between valve opening and Chlorophyll-a was found. Additionally, valve gape activity and tidal movement appeared to be linked. When exposed to a full tidal cycle (Voordelta), a negative correlation between valve opening and Chlorophyll-a was found. However, there was no correlation between valve gape and current velocity. In autumn, longer periods of inactivity were seen, but when valves opened, the valve gape was larger. These data indicate that valve gape can provide valuable information on behaviour (gape frequency and gape width), but also show that it is not necessarily a good proxy for feeding rate. Nevertheless, these results show that the gape monitor can be used to determine the natural behaviour of flat oysters under field conditions, and that gape opening provides information on behaviour and the stress response of bivalves to environmental conditions

Prospective biomarkers of major depressive disorder: a systematic review and meta-analysis

Leading biological hypotheses propose that biological changes may underlie major depressive disorder onset and relapse/recurrence. Here, we investigate if there is prospective evidence for biomarkers derived from leading theories. We focus on neuroimaging, gastrointestinal factors, immunology, neurotrophic factors, neurotransmitters, hormones, and oxidative stress. Searches were performed in Pubmed, Embase and PsychInfo for articles published up to 06/2019. References and citations of included articles were screened to identify additional articles. Inclusion criteria were having an MDD diagnosis as outcome, a biomarker as predictor, and prospective design search terms were formulated accordingly. PRISMA guidelines were applied. Meta-analyses were performed using a random effect model when three or more comparable studies were identified, using a random effect model. Our search resulted in 67,464 articles, of which 75 prospective articles were identified on: Neuroimaging (N = 24), Gastrointestinal factors (N = 1), Immunology (N = 8), Neurotrophic (N = 2), Neurotransmitters (N = 1), Hormones (N = 39), Oxidative stress (N = 1). Meta-analyses on brain volumes and immunology markers were not significant. Only cortisol (N = 19, OR = 1.294, p = 0.024) showed a predictive effect on onset/relapse/recurrence of MDD, but not on time until MDD onset/relapse/recurrence. However, this effect disappeared when studies including participants with a baseline clinical diagnosis were removed from the analyses. Other studies were too heterogeneous to compare. Thus, there is a lack of evidence for leading biological theories for onset and maintenance of depression. Only cortisol was identified as potential predictor for MDD, but results are influenced by the disease state. High-quality (prospective) studies on MDD are needed to disentangle the etiology and maintenance of MDD

Gradual versus episodic lateral saltmarsh cliff erosion: Evidence from Terrestrial Laser Scans (TLS) and Surface Elevation Dynamics (SED) sensors

As lateral erosion can threaten valuable saltmarsh habitats and their capacity to protect the hinterland from waves and floods, there is a need to understand the mechanisms of erosion. We monitored lateral saltmarsh erosion at high spatiotemporal resolution during a 2.5 year period. We performed terrestrial laser scans (TLS) with centimetric spatial resolution, ca monthly, as well as before and after 2 wind events to assess morphological change of a saltmarsh cliff

Culturing Chaetoceros muelleri using simplified media with different N sources: effects on production and lipid content

Land-based bivalve aquaculture depends on large-scale cultures of live microalgae for food. The intensity of large-scale microalgal production is important for cost-effectiveness. Using Walne’s medium as the control, simplified media containing nitrogen, phosphorus, silica, iron, manganese and vitamins were designed to determine the impact of nitrogen source and molar N:P ratio (sodium nitrate, NO3 9:1, ammonium chloride, NH4 9:1 and NH4 25:1) on growth, dry-weight biomass, culture longevity and lipid content of Chaetoceros muelleri, a diatom commonly used in shellfish aquaculture. During the exponential phase (day 6), dry-weight production in simplified media was similar to controls, indicating that this microalga can grow successfully on simplified media and use ammonium as the nitrogen source. The cultures grown on nitrate or ammonium differed in their time-course. Low nitrogen concentration in cultures grown with nitrate caused the collapse of these cultures within 11–13 days, after a short stationary phase. Cultures grown with ammonium had a longer stationary phase and were still alive on day 20, in spite of the low nitrogen concentrations observed after day 13 in cultures grown with NH4 9:1. During stationary phase (day 18) there was an increase in lipid content of algae under conditions of low nitrogen availability (NH4 9:1) and extended low phosphorus availability (NH4 25:1). Considering dry weight production, culture longevity, nutrient efficiency and lipid composition, simplified media containing ammonium, phosphorus, silica, iron, manganese and vitamins are a viable and profitable choice for batch culture of C. muelleri. In the exponential phase, the simplified medium NH4 9:1 was as effective as the control. Overall, both of the simplified media using ammonium are effective and suitable, depending on the purpose of the cultures and whether lipid contents (NH4 9:1), dry weight biomass (NH4 25:1) or nitrogen input and output (NH4 9:1) are desired

Survival probabilities of thornback and spotted rays discarded by beam trawl and flyshoot fisheries

Elasmobranchs (i.e. sharks, skates and rays) play an important role as predators in marine ecosystems. In the last century the abundance of several skates and rays in the North Sea declined. Their specific life-history traits, i.e. being long-lived, showing slow growth, late sexual maturity and producing a small number of young per year, make them vulnerable to fishing, pollution and changes in essential habitats, especially spawning and nursery areas. Since 2010 a recovery in the abundances of some species is observed. Landings of skates and rays in European waters are generally managed by a group-TAC, meaning several species are managed under a single Total Allowable Catch (TAC). In the North Sea this group-TAC applies to thornback (Raja clavata), blonde (Raja brachyura), spotted (Raja montagui) and cuckoo ray (Leucoraja naevus). Landings of starry ray (Amblyraja radiata) and common skate (Dipturus sp.) are prohibited. In Dutch fisheries, skates and rays are mainly caught as by-catch in the mixed demersal fishery for flatfish, with landings dominated by thornback ray. For these species the rays below minimum landing size and catches that exceed the vessel’s weekly trip limits are discarded. Since 2019 this practise of discarding has been restricted for all quota regulated species, including rays, by the implementation of a landing obligation under the Common Fisheries Policy (European Union, 2013). The objective of the landing obligation is to create an incentive for fishers to avoid unwanted bycatches and thereby reduce discards rates. The European commission granted a temporary ‘high survival’ exemption for rays and indicated that for this exemption to be renewed or extended beyond 2023, knowledge gaps regarding discards survival probabilities of rays, as laid out in the “Roadmap skates and rays”, need to be filled. The current study therefore aims to contribute to this roadmap by filling main gaps in our knowledge on the survival probability of rays when discarded by the most important Dutch demersal fisheries. Beam trawl and flyshoot fisheries are quantitatively the main contributors to ray catches by Dutch demersal fisheries with thornback and spotted ray as main species. These two métiers and species were therefore selected for the discards survival experiments. We conducted five trips with a beam trawler during which 184 thornback and 140 spotted rays were sampled and four trips with a flyshooter during which 134 thornback and 28 spotted rays were sampled. Survival probabilities were measured by captive observation of these rays up to 25 days post-capture. Control rays were used to separate potential effects of the experimental procedures on mortality from fisheries-induced mortality. All fishery operations were conducted in the southern North Sea (ICES division 27.4.c) and in the English Channel (ICES division 27.7.d) according to the regular commercial practices of the fishing vessels. Trips were allocated to different quarters over the year to account for the effect of variable environmental and fishing conditions on discards survival. Operational and environmental conditions during sea trips were recorded. In this study we established the following discards survival probabilities (95% CI): • 45.5% (37.9-54.5) for spotted ray discarded by tickler chain beam trawl fisheries with 80 mm cod-end meshes; • 49.6% (42.9-57.4) for thornback ray discarded by tickler chain beam trawl fisheries with 80 mm cod-end meshes; • 77.6% (63.3-95.2) for spotted ray discarded by flyshoot fisheries with 80 mm cod-end meshes; • 81.0% (74.4-88.2) for thornback ray discarded by flyshoot fisheries with 80 mm cod-end meshes. The experimental procedures did not cause any mortality since all control rays survived the experiments. All mortality among sampled rays can thus be considered to be fisheries induced. Survival probability was higher for rays discarded by flyshoot fisheries compared to beam trawl fisheries. Survival probability of discarded rays decreased with increasing seawater temperature and some evidence for decreasing survival with increasing catch processing time was found. Species and body length did not affect survival probability. Survival probability was highest for rays that were landed on deck in good condition. To further increase survival probability it is recommended to keep catch processing time as short as possible and to focus on gear modifications that reduce stressors inflicted upon fish during the catch and hauling process to increase the proportion of rays that is landed on deck in good condition. In addition, we recommend to pursue reduction of fishing mortality among rays by reducing the amount of caught rays by improved selectivity of fishing gear and by actively avoiding fishing grounds where rays occur in high densities