2,988 research outputs found
Use of baited remote underwater video (BRUV) and motion analysis for studying the impacts of underwater noise upon free ranging fish and implications for marine energy management
© 2016 Elsevier Ltd Free-ranging individual fish were observed using a baited remote underwater video (BRUV) system during sound playback experiments. This paper reports on test trials exploring BRUV design parameters, image analysis and practical experimental designs. Three marine species were exposed to playback noise, provided as examples of behavioural responses to impulsive sound at 163–171 dB re 1 μPa (peak-to-peak SPL) and continuous sound of 142.7 dB re 1 μPa (RMS, SPL), exhibiting directional changes and accelerations. The methods described here indicate the efficacy of BRUV to examine behaviour of free-ranging species to noise playback, rather than using confinement. Given the increasing concern about the effects of water-borne noise, for example its inclusion within the EU Marine Strategy Framework Directive, and the lack of empirical evidence in setting thresholds, this paper discusses the use of BRUV, and short term behavioural changes, in supporting population level marine noise management
Sensitivity of Pagurus bernhardus (L.) to substrate-borne vibration and anthropogenic noise
© 2015 Elsevier B.V. Despite the prevalence of vibration produced by anthropogenic activities impacting the seabed there are few data and little information as to whether these are detected by crustaceans and whether they interfere with their behaviour. Here the sensitivity of unconditioned Pagurus bernhardus to substrate-borne vibration was quantified by exposure to sinusoidal vibrations of 5-410Hz of varied amplitudes using the staircase method of threshold determination, with threshold representing the detection of the response and two behavioural responses used as reception indicators: movement of the second antenna and onset or cessation of locomotion. Thresholds were compared to measured vibrations close to anthropogenic operations and to the time in captivity prior to tests. Behaviour varied according to the strength of the stimulus with a significant difference in average threshold values between the two behavioural indicators, although there was an overlap between the two, with overall sensitivity ranging from 0.09-0.44ms -2 (root mean squared, RMS). Crabs of shortest duration in captivity prior to tests had significantly greater sensitivity to vibration, down to 0.02ms -2 (RMS). The sensitivity of P. bernhardus fell well within the range of vibrations measured near anthropogenic operations. The data indicate that anthropogenic substrate-borne vibrations have a clear effect on the behaviour of a common marine crustacean. The study emphasises that these vibrations are an important component of noise pollution that requires further attention to understand the long term effects on marine crustaceans
Behavioural responses by marine fishes and macroinvertebrates to underwater noise
The aim of this thesis was to explore and evaluate the key behavioural responses of coastal UK marine fishes and macroinvertebrates to anthropogenic noise. Work focussed upon two key aspects, water-borne acoustics and the relatively unstudied substrate-borne vibration, with a combination of laboratory and field work using grouped and solitary individuals. A literature review on underwater vibroacoustics, detection abilities, anthropogenic noise sources and the effects of such stimuli was provided (Chapter 1).Playbacks were undertaken in the field using a purpose-built underwater transducer array capable of accurately reproducing man-made signatures (Chapter 2 – 3). The behavioural responses of wild, unrestrained schooling pelagic fish to impulsive sound were observed using an acoustic observation system. Precise exposure levels were linked to specific responses, with dose response curves produced for two pelagic species of varied hearing abilities. Baited remote underwater video (BRUV) was used to observe the behavioural responses of free-ranging individual fish and crustaceans exposed to impulsive sound and shipping noise. In both cases responses varied according to the level of sound, the type of school and the species.In the laboratory, animals were exposed to sinusoidal vibratory signals using a fully calibrated electromagnetic shaker system. The sensitivity of unconditioned invertebrates (crustaceans and molluscs) to substrate-borne vibration was quantified with controlled vibratory exposures, allowing the production of a sensory threshold curve for three species (Chapters 4 - 5). Response variation was described in terms of two behavioural indicators, and related to consistency within individuals (personality), morphological parameters and time in the laboratory prior to tests. Further work investigated the response of sessile invertebrates to vibration, with the observations fully described in terms of response occurrence, duration and variation for both grouped and solitary animals.The responses described in each chapter were related to actual measurements of anthropogenic noise sources in terms of water-borne and substrate-borne energy, allowing behavioural responses to be translated to actual conditions. The data here provide evidence for the levels of playback sound to induce a behavioural response, and are fully reproducible to allow further testing of the responsiveness of fish to different sound levels and signatures. Furthermore, the data are a first step towards understanding the sensitivity of benthic invertebrates to substrate-borne vibration and indicate that the effects of substrate transmission should not be overlooked when investigating the effects of noise pollution on the marine environment. The results from the current work, along with the recommendations for future work, will be important to aid the filling of the ‘information gaps’ that exist within the underwater bioacoustics field
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An exploration of Key Stage 3 girls' peer group friendships outside the class-room and their influence within the class-room
Whilst there is some literature in the UK and internationally surrounding both peer groups and their activities during break-times and more generally group-work within the class-room, there is no research, as yet, that focuses specifically on the influence that peer groups' activity during break-times has on pedagogy. This is an under-explored and under-theorised area which suggests that there is little understanding in education of how social relationships outside the class-room influence learning within the class-room. Moreover, much of the available literature focusing on teaching and learning seems to have been underpinned by traditional models of learning.
This research seeks to highlight the importance of friendships and its direct relationship with learning through the exploration and application of the socio-cultural theory (in particular through the work of Vygotsky and his zone of proximal development, Lave and Wenger's (1998) Communities of Practice literature and Bronfenbrenner's (1979) ecological approach). Here, learning is reconceptualised by moving the focus away from the individual in isolation and the personal, towards a focus on the social and active participation.
This qualitative research Main Study was carried out within the autumn term in a secondary school in Wales. Taking part in the research were a total of forty-four female pupils (all within Key Stage 3) and eight teachers. The pupils participated in focus groups (which were all tape-recorded) and one friendship group from each year volunteered for participant observation which took place over two full days per group. The teachers were all interviewed individually using semi-structured interviews.
The data from the field was all transcribed and analysed using the socio-cultural framework. A narrative was also written to help to provide a more holistic view of the data and to help situate the experience of friendships within the whole school day. One main over-riding theme emerged from the transcription, that of 'the secret world of friendship'. The theme revealed how much of peer group activity during break-times was opaque to many teachers and how pupils played out their powerlessness within the class-room in the face of oppression (due to the way that the education system is presently structured). Many secret notes were passed around and personal objects used as acts of resistance.
The data showed that negotiating identities (by curtailing the tension between the personal and the social) and generally managing social relationships were a key element in a school pupil's life and important in their overall identity, but this area still remains predominantly secret to, or ignored by, many teachers. The socio-cultural approach highlights many of the tensions that are embedded within the present structure of the education system as it stands. By adopting this approach, or gaining an awareness of its key premises, the personal and the social become reunited and peer groups can become a positive and productive part of learning
Development of a smartphone app-based intervention to promote physical activity among people living with and beyond cancer
With increasing numbers of people being diagnosed with cancer, and living for many years after diagnosis, it is important that cancer survivors are supported to live well, for as long as possible. Physical activity improves quality of life and many treatment side effects after cancer. Physical activity is important in reducing the risk of other common comorbid conditions and may prolong survival in cancer survivors. However, many cancer survivors do not meet recommended levels of physical activity and evidence-based interventions that are accessible and that could be implemented at scale are needed. The rising use of the internet, smartphones and mobile technology mean that digital interventions could reach large proportions of the population in a way that could be more cost-effective and scalable. This thesis used mixed-methods to conduct a series of studies with the aim of developing a smartphone-app based intervention to promote physical activity in breast, prostate and colorectal cancer survivors. Study 1 showed that digital interventions have the potential to increase cancer survivors’ moderate-vigorous physical activity by 41 minutes per week, however high-quality studies are lacking. Study 2 found that 38% and 24% of breast, prostate and colorectal cancer survivors respectively are interested in internet-based and app-based health behaviour interventions. Interest is related to several sociodemographic and participant characteristics. Study 3 found that physical activity apps must acknowledge the varying needs and physical activity preferences of cancer survivors. Apps that promote walking and are recommended to them by members of their clinical team (particularly Clinical Nurse Specialists) are favoured. Study 4 provided insight into Clinical Nurse Specialists’ perceptions of their role in physical activity promotion and showed that they are generally positive about the use of apps to complement existing physical activity promotion in cancer care. Together, these studies led to the development of an app-based physical activity intervention for cancer survivors
Electrochemical and structural studies of organometallic acetylide complexes
This thesis describes the synthesis and properties of systems of the general type ML(_x)-bridge- ML(_x), and related 'mixed-valence' derivatives. The efficacy of the l.l'-ferrocenediyl unit (Fc') as a bridge between two redox-active metal centres, is investigated by examination of the properties of a series of complexes, 1,1'-{Cp'(PP)RuC=C}(_2)Fc’, and the related binuclear model systems Ru(C=CFc)(PP)Cp'. Whilst interactions through an ethyndiyl bridge occur between one Ru(PP)Cp' moiety and a ferrocenyl centre, in the l,l'-{Cp'(PP)RuC=C}(_2)Fc' systems no interaction between the terminal Ru(PP)Cp' groups is observed. A comparative study of the redox and spectroscopic properties of the family of complexes [{Ru}(_2)(u-C≡CXC≡C)](^n+) [{Ru} = Ru(PPh(_3))(_2) Cp, Ru(dppe)Cp*; X = 1,4- C(_6)H(_4), l,4-C(_10)H(_6), 9,10-C(_14)H(_8); n = 0, 1, 2] is presented, together with those of the related mononuclear compounds. Comparison of the results with DFT calculations of the electronic structure allows the properties of the diethynylaryl-bridged, bimetallic complexes to be rationalised in terms of a significant contribution of the diethynylaryl bridging ligand to the SOMO. The electronic properties of the 1,12-diethynyl carborane-bridged species 1,12- {Ru(dppe)Cp*}(_2)(u-C≡C-CB(_10)H(_10)C-C≡C), and the related mononuclear complex Ru(C≡C-CB(_10)H(_10)H)(dppe)Cp*, are assessed by a combination of electrochemical and spectroscopic techniques. The results allow a comparison of the 'three-dimensional' aromatic spacer l,12-C(_2)BH(_10) with the phenylene analogue. Explorations of the acetylide chemistry of the Fe(dppe)’_n’ fragment are described. The resulting air stable complexes provide a convenient entry point to the acetylide chemistry of the octahedral iron fragment. The details of additional crystal structures obtained by single crystal X-ray diffraction methods, together with a brief description of the chemistry associated with them, are presented in the appendix
State of bills of rights 1776-1837
The purpose of this particular work is to study the State Bills of Rights and to discover what political philosophy express. To the knowledge of the author, this has never been attempted, therefore secondary sources were of value to her only as background material
Are restoration plantings an ecological success? : a thesis submitted in fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University, Palmerston North
Ecological restoration is a rapidly expanding practice that has developed in response to worldwide loss of habitat and ecosystem services. However, the success of this practice in restoring a functioning and representative ecological system remains poorly studied and uncertain. This is due to several factors predominantly, restricted funds, a knowledge gap between practitioners and the developing scientific field of restoration ecology, and the length of time it takes for some ecological systems to recover. In New Zealand restoration planting has occurred in large areas since the 1980s. These have now established canopies with unassisted seedling regeneration, making predictions of successional trajectory and ecological success assessments possible.
The ecological restoration of forests is most commonly carried out through dense planting of native seedlings. This study aims to measure the ecological success of this planting method within New Zealand lowland podocarp-broadleaved forests comparing it with a ‘do-nothing’ control site undergoing unassisted secondary succession and a reference site of the desired target community (mature lowland forest). Restoration success was determined by the Planted Site being closer than the Spontaneous Succession Site to the Reference Site in vegetation community composition within ordinational space (principal coordinates analysis).
It was found that the vegetation community within the Spontaneous sites was more comparable to the Reference sites than the Planted sites and thus, more successful. The compositional differences between the spontaneous and planted sites were further investigated by analysing environmental and structural variables of each site sampled to find explanatory variables that may be driving the success of forest restoration (in directing the successional process towards the desired target community within a reference site). A nested multivariate analysis of the plot data and generalised linear modelling of each site was carried out to find potential explanatory variables which highly correlated to restoration success (how close a site was to its reference).
Potential explanatory variables correlating to restoration success included; a lower diversity (Shannon Wiener Index) in the restoration plantings in both species richness and within the structural and function classifications of each species; a greater diversity of vegetation tiers; a fewer number of stems at breast height per individual tree; shorter canopy heights; smaller canopy diameters uncompacted soil; a greater diversity in microtopography; and a greater coverage of ground ferns.
These explanatory variables were then modelled using Akaike’s Information Criterion to identify both descriptive and driving parameters. The Akaike models identified 16 different parameters as related to the compositional differences when plotted in ordination space. High diversity within all three measured attributes (composition, structure and function) and presence of ferns are clearly descriptors of the success of Spontaneous succession here, while lessor soil compaction and diversity in microtopography at the site could be drivers. This success is demonstrated by soil compaction and a diversity in each of the species attribute classifications of structure, function and composition.
In conclusion spontaneous succession was found to be more successful. This is likely due to uncompacted soils, a greater microsite variation, a higher diversity of species, functional groups and structural characters. Further, the secondary successional dependence on functioning soils is confirmed here, as well as the presence of indicator species such as ground ferns. Management implications of these findings suggest passive restoration methods should firstly be considered in forest restoration. If in addition, planting is also considered necessary, accelerating and directing secondary succession requires more attention to pre-planting preparation of sites and of species selection
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