The ecology of larval and juvenile fishes in lowland rivers, with particular emphasis on foraging

FEEDING ECOLOGY OF 0+ FISHESThere are numerous biotic and abiotic factors that affect the abundance of cyprinid fish stocks in rivers, many of which are poorly understood. The role of food availability during critical life stages is one of these factors that may determine the growth and survival of 0+ fishes, and ultimately their recruitment to adulthood. Until the main factors affecting recruitment of cyprinid fishes are better understood, informed/appropriate management actions cannot be undertaken. For this reason temporal, spatial and inter-specific influences affecting the prey availability, feeding ecology and condition of 0+ fishes were studied in experimental and wild conditions to improve the understanding of feeding ecology for 0+ fishes in rivers and the effect this has on the health of the individual fish.This study revealed diel variation in fish species composition, prey availability, diet composition, feeding activity and prey selection of larval and 0+ juvenile fishes. Five surveys were carried out in total, until the fishes reached juvenile stage, in the River Trent. There was circumstantial evidence of zooplankton migration in some species, for example, densities of Rotifera in the margins declined at night, suggesting migration into open waters. Densities of 0+ fishes were generally higher at night in three surveys, but higher in daylight in two surveys. This may have been a result of predator avoidance as more >0+ pike and perch were found in the margins at night. There was also a significant increase in spined loach and bullhead at night compared to daylight. Gut fullness of 0+ juvenile roach and perch increased at night, but there was a reduction in gut fullness at night for larval roach and perch, suggesting a switch in feeding behaviour during ontogeny that was also evident in electivity indices and prey availability. Seasonal variations in prey availability and feeding ecology of 0+ roach and bream were studied on the River Trent, which revealed a significant reduction in feeding activity of both species from summer to winter, but this did not affect the condition of the fishes, which remained constant across all seasons. Significant seasonal differences in the diet composition were found in 0+ bream, but not 0+ roach.Spatial variations in prey availability (composition, density and diversity), feeding ecology (diet composition, feeding activity and prey selection) and condition of 0+ fishes were studied using point abundance sampling on a mesohabitat scale in the River Ancholme to investigate the influence of habitat type (floating-leaved, emergent or submerged vegetation). The highest densities of most zooplankton taxa were found in emergent and floating-leaved vegetation (the least complex habitats) compared with submerged vegetation (the most complex). Feeding activity was higher for larval and 0+ juvenile roach than bream in all vegetation categories. Gut fullness of larval roach was highest in submerged vegetation, suggesting that the complex structure did not affect the feeding activity of 0+ roach. In general, selection was higher in simple vegetation categories than complex vegetation categories, even though the same prey was available in most habitats, indicating that prey availability was not the only factor influencing feeding ecology of 0+ roach and bream and that habitat complexity influences prey choice. Nonetheless, this did not influence the condition of roach and bream between the different vegetation categories, which remained constant.The effects of interspecific interactions on the diet composition, prey selection, growth and condition of 0+ roach and bream were studied in allopatric (single-species) and sympatric (mixed-species) fish populations established in enclosures at Calverton Fish Farm, Nottinghamshire. This study found a significant influence of interspecific interactions on the diet composition and prey selection of 0+ fishes. There was evidence of resource partitioning when roach and bream larvae were in sympatry, which suggested that feeding behaviour of both species was negatively affected by interspecific interactions. By comparison, interspecific interactions had no significant influence on the length, weight or weight-length relationships of 0+ roach and bream. In addition, the condition of roach was not affected by the presence of bream, but there was a small but significant deterioration in the condition of bream in the presence of roach. These results were compared to wild conditions in the River Trent, which generally supported the findings at Calverton even though the densities at Calverton were higher. This information will improve understanding of the feeding ecology of 0+ fishes during early development, which can be used in the management and rehabilitation of fish populations and fluvial habitats, as well as improving growth and survival in aquaculture facilities, and inform research sampling strategies when studying juvenile fish populations

Diel variations in the assemblage structure and foraging ecology of larval and 0+ year juvenile fishes in a man-made floodplain waterbody

© 2016 The Fisheries Society of the British Isles. This study investigated diel variations in zooplankton composition and abundance, and the species composition, density, size structure, feeding activity, diet composition and prey selection of larval and 0+ year juvenile fishes in the littoral of a man-made floodplain waterbody over five 24 h periods within a 57 day period. There was a significant difference in the species composition of diurnal and nocturnal catches, with most species consistently peaking in abundance either during daylight or at night, reflecting their main activity period. There were no consistent diel patterns in assemblage structure or the abundance of some species, however, most likely, respectively, due to the phenology of fish hatching and ontogenetic shifts in diel behaviour or habitat use. There were few clear diel patterns in the diet composition or prey selection of larval and 0+ year juvenile roach Rutilus rutilus and perch Perca fluviatilis, with most taxa consistently selected or avoided irrespective of the time of day or night, and no obvious shift between planktonic and benthic food sources, but dietary overlap suggested that interspecific interactions were probably strongest at night. It is essential that sampling programmes account for the diel ecology of the target species, as diurnal surveys alone could produce inaccurate assessments of resource use. The relative lack of consistent diel patterns in this study suggests that multiple 24 h surveys are required in late spring and early summer to provide accurate assessments of 0+ year fish assemblage structure and foraging ecology

Family foundations outcome evaluation

[Executive Summary] The ACT Community Services Directorate (CSD) commissioned the ACU Institute of Child Protection Studies (ICPS) to conduct a process and outcome evaluation of Family Foundations. CSD, a government agency responsible for various human services functions in the ACT, funds the Belconnen Community Service to deliver Family Foundations. Family Foundations is an early intervention therapeutic program designed to promote strong, secure and healthy relationships between children aged 0-5 years and their parents/carers. ICPS evaluators finalised the process evaluation in February 2018. It assessed the extent to which Family Foundations had been implemented as intended (see Barker, Thorpe and McArthur, 2018). The outcome evaluation assessed the extent to which Family Foundations achieved intended outcomes. It involved a mixed methods approach. This approach involved collecting, analysing and interpreting qualitative and quantitative data to address the key evaluation questions. The available evidence suggested that Family Foundations enhanced parenting capacity and contributed to improved outcomes for children. Changes in parenting capacity were evident in the test scores for quantitative outcome tools and the qualitative accounts of parents, practitioners and stakeholders. Test scores typically showed small, but statistically significant, improvements post-program participation. Parents, practitioners and stakeholders provided rich descriptions of how participating in Family Foundations had developed parenting knowledge and skills and improved parents’ sense of self-confidence in their ability to meet their child’s needs. Most parents noted an improved ability to recognise and manage their emotions when caring for their child. Parents and practitioners reported improvements in the emotional regulation and behavioural outcomes of their children. Parental participation in Family Foundations also appeared to have enhanced the quality of the parent-child attachment. ICPS evaluators identified an unintended consequence for one parent who had participated in the program. This parent exited Family Foundations with lasting feelings of distress. While unfortunate, this experience appeared to be a consequence of the practitioner acting in the interests of the child. Available evidence suggested that program staff adopted process to keep the focus on the child and supported parents to understand the importance of this focus even in the event it may cause the parent discomfort. A significant implication of the evaluation relates to whether Family Foundations reached the ‘right’ parents. Many parents entered Family Foundations with pre-program test scores that fell in the moderate band. While these families experienced improvements, the change was small. Yet, when the program engaged parent who demonstrated high need at the point of entry, the change in test scores post-program participation was more substantial than for parents with low to moderate parenting need. The important message here is that Family Foundations appeared to produce the most significant result for parents in greater need. ICPS evaluators recommend further reflection on whether BCS is appropriately set up to deliver ‘blended prevention’ (Prinz, 2015) – combining universal and targeted parenting supports in an integrated strategy

“Chains Weigh Heavy”: Body Mapping Embodied Experiences of Anxiety

Anxiety has both cognitive and somatic dimensions as is ubiquitous at a population level. We report on an arts-based research workshop gathering data on embodied experiences of anxiety and non-anxiety. We developed an innovative short body mapping workshop to collect data and undertook thematic analysis to analyse textual and visual data. 35 body maps were produced. “Tightness,” “pain,” and “heaviness” were the most frequently expressed embodied sensations of anxiety. By contrast, when not feeling anxious, participants’ bodies primarily felt “energetic,” “ordered,” and “open.” Anxiety was most frequently felt in the stomach, head and heart. 35 Participants mostly used an abstracted, rather than figurative, visual language to depict anxiety. Conclusions: Participants reported diverse bodily experiences of anxiety, some of which correlate with commonly identified somatic symptoms of anxiety. Other symptoms were unique to participants. The richness and diversity of anxiety experiences elicited during workshops indicates that the brief body mapping approach has potential application in future research, and in other settings

Digital Storytelling in Research: A Systematic Review

Digital storytelling refers to a 2 to 5 minute audio-visual clip combining photographs, voice-over narration, and other audio (Lambert, 2009) originally applied for community development, artistic and therapeutic purposes, and more recently adapted as an arts-based research method. To date, no systematic review of the use of digital storytelling in a research capacity, to generate information about a phenomenon has been conducted. Accordingly, our aim was to provide a systematic review of digital storytelling in research. The review identified 25 articles representing 23 discrete studies that met inclusion criteria. A thematic analysis of results indicated that digital storytelling in research was especially appropriate for use with marginalised groups, and was most commonly used in this context. There was some variation in the extent to which digital storytelling in research adhered to the principles with which it was originally developed. Surprisingly, although digital storytelling provides a ready-made knowledge translation product, few research projects employed the digital stories generated to this end. Across research projects, participants reported several benefits of digital storytelling. While some disadvantages were noted, overall, these were outweighed by the benefits of using a respectful, participatory research practice

Temporal and spatial variations in the abundance and population structure of the spined loach (Cobitis taenia), a scarce fish species: implications for condition assessment and conservation

Effective conservation of protected species requires accurate estimates of the status of their populations. In the UK, this led to the production of a series of sampling protocols to establish the status of designated species against predetermined conservation objectives: a process known as 'condition assessment'. Condition assessments involve comparisons of various parameters, invariably including abundance and/or population structure, of the target species against criteria that are judged to be indicative of viable populations.This study investigated temporal and spatial variations in the abundance and population structure of spined loach (Cobitis taenia), a scarce species indigenous to Europe and central Asia. Specifically, the study compared the density, number of age classes and percentage contribution of the 0+ year age class of spined loach between day and night, months, years and locations.There were marked diel, seasonal, annual and spatial variations in the density, number of age classes and percentage contribution of 0+ year spined loach. Such phenomena are important because monitoring programmes conducted at inappropriate times of day or year, or with insufficient frequency or geographical coverage, could lead to inaccurate assessments of the condition of protected populations and, consequently, to inadequate conservation measures. Notwithstanding, there were few impacts on the condition assessments of the spined loach populations because at least one of the parameters invariably failed to satisfy the population condition assessment criteria.A prerequisite for successful conservation is an effective monitoring programme. It is therefore essential that surveys to assess the condition of populations of protected species are designed with due consideration of their diel behaviour, breeding season, life span and habitat use. It is recommended that the monitoring protocol and condition assessment criteria for spined loach are amended, and that surveys are conducted by trawling, in late summer, at least every 3-4years

Analyzing kinetic signaling data for G-protein-coupled receptors

In classical pharmacology, bioassay data are fit to general equations (e.g. the dose response equation) to determine empirical drug parameters (e.g. EC50 and Emax), which are then used to calculate chemical parameters such as affinity and efficacy. Here we used a similar approach for kinetic, time course signaling data, to allow empirical and chemical definition of signaling by G-protein-coupled receptors in kinetic terms. Experimental data are analyzed using general time course equations (model-free approach) and mechanistic model equations (mechanistic approach) in the commonly-used curve-fitting program, GraphPad Prism. A literature survey indicated signaling time course data usually conform to one of four curve shapes: the straight line, association exponential curve, rise-and-fall to zero curve, and rise-and-fall to steady-state curve. In the model-free approach, the initial rate of signaling is quantified and this is done by curve-fitting to the whole time course, avoiding the need to select the linear part of the curve. It is shown that the four shapes are consistent with a mechanistic model of signaling, based on enzyme kinetics, with the shape defined by the regulation of signaling mechanisms (e.g. receptor desensitization, signal degradation). Signaling efficacy is the initial rate of signaling by agonist-occupied receptor (kτ), simply the rate of signal generation before it becomes affected by regulation mechanisms, measurable using the model-free analysis. Regulation of signaling parameters such as the receptor desensitization rate constant can be estimated if the mechanism is known. This study extends the empirical and mechanistic approach used in classical pharmacology to kinetic signaling data, facilitating optimization of new therapeutics in kinetic terms

PKC-dependent Phosphorylation of the H1 Histamine Receptor Modulates TRPC6 Activity

Transient receptor potential canonical 6 (TRPC6) is a cation selective, DAG-regulated, Ca2+-permeable channel activated by the agonists of Gq-protein-coupled heptahelical receptors. Dysfunctions of TRPC6 are implicated in the pathogenesis of various cardiovascular and kidney conditions such as vasospasm and glomerulosclerosis. When stimulated by agonists of the histamine H1 receptor (H1R), TRPC6 activity decays to the baseline despite the continuous presence of the agonist. In this study, we examined whether H1R desensitization contributes to regulating the decay rate of TRPC6 activity upon receptor stimulation. We employed the HEK expression system and a biosensor allowing us to simultaneously detect the changes in intracellular diacylglycerol (DAG) and Ca2+ concentrations. We found that the histamine-induced DAG response was biphasic, in which a transient peak was followed by maintained elevated plateau, suggesting that desensitization of H1R takes place in the presence of histamine. The application of PKC inhibitor Gö6983 slowed the decay rate of intracellular DAG concentration. Activation of the mouse H1R mutant lacking a putative PKC phosphorylation site, Ser399, responsible for the receptor desensitization, resulted in a prolonged intracellular DAG increase and greater Mn2+ influx through the TRPC6 channel. Thus, our data support the hypothesis that PKC-dependent H1R phosphorylation leads to a reduced production of intracellular DAG that contributes to TRPC6 activity regulation

Recovery and purification of no-carrier-added [18F]fluoride with bistrimethylsilylsulfate (BTMSS)

No-carrier-added trimethylsilyl[18F]fluoride (TMS[18F]F) was rapidly liberated from a variety of dry supports containing unreactive [18F]fluoride by simply heating with neat bistrimethylsilylsulfate. The supports included calcium phosphate, anion exchange resins, alumina, borosilicate and porous carbon beads, to which [18F]fluoride was applied by absorption or evaporation of aqueous solution. TMS[18F]F was evolved essentially free of entrained moisture or excess silylating agent and was efficiently absorbed and rapidly cleaved to free [18F]fluoride ion by 0.1% benzyltrimethylammonium methoxide in anhydrous methanol. Passage of this solution through a strong cation exchange column provided purified hydrogen[18F]fluoride, which was subsequently trapped on a quaternary 4-aminopyridinium resin and used for heterogeneous nucleophilic radiofluorination of 1,3,4,6-tetraacetyl-beta-mannopyranose-2-triflate in 70% yield. The purified [18F]fluoride was also used for solution phase nucleophilic labeling of ethyl [18F]4-fluorobenzoate following addition of K2CO3/Kryptofix and DMSO. This approach provides a simplified way to ensure high reactivity in [18F]fluoride ion from cyclotron targets. It also may be used to salvage active [18F]fluoride ion from insoluble complexes and radiofluorination reaction residues.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29654/1/0000743.pd