227 research outputs found

    Religion and the development of an urban society : Glasgow 1780-1914

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    Introduction available: v. 1

    Diving behaviour of whale sharks in relation to a predictable food pulse

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    We present diving data for four whale sharks in relation to a predictable food pulse (reef fish spawn) and an analysis of the longest continuous fine-resolution diving record for a planktivorous shark. Fine-resolution pressure data from a recovered pop-up archival satellite tag deployed for 206 days on a whale shark were analysed using the fast Fourier Transform method for frequency domain analysis of time-series. The results demonstrated that a free-ranging whale shark displays ultradian, diel and circa-lunar rhythmicity of diving behaviour. Whale sharks dive to over 979.5 m and can tolerate a temperature range of 26.4 degrees C. The whale sharks made primarily diurnal deep dives and remained in relatively shallow waters at night. Whale shark diving patterns are influenced by a seasonally predictable food source, with shallower dives made during fish spawning periods

    A petrographic investigation into the durability of common replacement sandstones to the crystallisation of de-icing salts

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    Scottish sandstone buildings are now suffering the long-term effects of salt-crystallisation damage, owing in part to the repeated deposition of de-icing salts during winter months. The use of de-icing salts is necessary in order to maintain safe road and pavement conditions during cold weather, but their use comes at a price. Sodium chloride (NaCl), which is used as the primary de-icing salt throughout the country, is a salt known to be damaging to sandstone masonry. However, there remains a range of alternative, commercially available de-icing salts. It is unknown however, what effect these salts have on porous building materials, such as sandstone. In order to protect our built heritage against salt-induced decay, it is vital to understand the effects of these different salts on the range of sandstone types that we see within the historic buildings of Scotland. Eleven common types of sandstone were characterised using a suite of methods in order to understand their mineralogy, pore structure and their response to moisture movement, which are vital properties that govern a stone’s response to weathering and decay. Sandstones were then placed through a range of durability tests designed to measure their resistance to various weathering processes. Three salt crystallisation tests were undertaken on the sandstones over a range of 16 to 50 cycles, which tested their durability to NaCl, CaCl2, MgCl2 and a chloride blend salt. Samples were primarily analysed by measuring their dry weight loss after each cycle, visually after each cycle and by other complimentary methods in order to understand their changing response to moisture uptake after salt treatment. Salt crystallisation was identified as the primary mechanism of decay across each salt, with the extent of damage in each sandstone influenced by environmental conditions and pore-grain properties of the stone. Damage recorded in salt crystallisation tests was ultimately caused by the generation of high crystallisation pressures within the confined pore networks of each stone. Stone and test-specific parameters controlled the location and magnitude of damage, with the amount of micro-pores, their spatial distribution, the water absorption coefficient and the drying efficiency of each stone being identified as the most important stone-specific properties influencing salt-induced decay. Strong correlations were found between the dry weight loss of NaCl treated samples and the proportion of pores <1µm in diameter. Crystallisation pressures are known to scale inversely with pore size, while the spatial distribution of these micro-pores is thought to influence the rate, overall extent and type of decay within the stone by concentrating crystallisation pressures in specific regions of the stone. The water absorption determines the total amount of moisture entering into the stone, which represents the total amount of void space for salt crystallisation. The drying parameters on the other hand, ultimately control the distribution of salt crystallisation. Those stones that were characterised by a combination of a high proportion of micro-pores, high water absorption values and slow drying kinetics were shown to be most vulnerable to NaCl-induced decay. CaCl2 and MgCl2 are shown to have similar crystallisation behaviour, forming thin crystalline sheets under low relative humidity and/or high temperature conditions. Distinct differences in their behaviour that are influenced by test specific criteria were identified. The location of MgCl2 crystallisation close to the stone surface, as influenced by prolonged drying under moderate temperature drying conditions, was identified as the main factor that caused substantial dry weight loss in specific stone types. CaCl2 solutions remained unaffected under these conditions and only crystallised under high temperatures. Homogeneous crystallisation of CaCl2 throughout the stone produced greater internal change, with little dry weight loss recorded. NaCl formed distinctive isometric hopper crystals that caused damage through the non-equilibrium growth of salts in trapped regions of the stone. Damage was sustained as granular decay and contour scaling across most stone types. The pore network and hydric properties of the stones continually evolve in response to salt crystallisation, creating a dynamic system whereby the initial, known properties of clean quarried stone will not continually govern the processes of salt crystallisation, nor indeed can they continually predict the behaviour of stone to salt-induced decay

    The Effect of Carbohydrate Mouth Rinsing on Multiple Choice Reaction Time During Amateur Boxing

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    Purpose: To examine whether the use of a carbohydrate mouth rinse (CMR) can improve multiple choice reaction time in amateur boxers during sparring. Methods: A total of 8 male amateur boxers (age 22 [3] y, stature 1.78 [0.07] m, mass 73.6 [14.2] kg) with at least 18 months of experience in the sport volunteered to participate in the study. All participants attended a familiarization session, followed by an experimental (CMR; 6% dextrose) and placebo trials in a randomized order. Participants undertook 3 × 2 minutes of sparring against an ability- and size-matched (stature and mass) opponent. Multiple choice reaction time and perceived exertion were measured before round 1 and then after each round. The respective mouth rinse was administered in a 25-mL solution for 10 seconds before each round. Magnitude-based inferences were used to compare the results of each round (mean difference; ±90% confidence limits). Results: The CMR was unlikely to have a beneficial effect on multiple choice reaction time compared with placebo (mean ± 90% confidence limits: 5 ± 9.5, 4 ± 3.4, −1 ± 8.5 lights for rounds 1 to 3, respectively) and had a possibly harmful effect on perceived exertion in round 1 (10 ± 20). There was an unlikely harmful effect on perceived exertion in rounds 2 (1 ± 12) and 3 (9 ± 23). Conclusion: There is no evidence to support the use of CMR during sparring in amateur boxers

    Rewilding – departures in conservation policy and practice? An evaluation of developments in Britain

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    Rewilding has been hailed as ‘radical’ and ‘agenda-setting’ in the challenge it poses to mainstream conservation. This paper questions whether that is still the case, or if rewilding is now being mainstreamed and with what consequences? Our analysis focuses upon developments in Britain, up until 2018, discussing what changes have become manifest and the barriers and restraints that have been observed. As such, we evaluate the extent to which rewilding – in practice - departs from longstanding conservation sensibilities. Discussion is structured around three key questions— Who is now involved in rewilding across Britain? What they are seeking to do, in terms of how nature is conceptualised and managed (or not)? In what ways do their objectives involve people and human-centred aspirations? Our findings reveal three key differences from current conservation approaches. First, rewilding is associated with a proliferation of new actors, new mechanisms of finance and new spaces of conservation interest. Second, rewilding as an approach exhibits clear novelty in its stated aim to be nature-led and, despite challenges, attempts to work through ongoing negotiation and experimentation. Finally, rewilding is currently being advocated and pursued as an agenda for people and nature, which moves beyond earlier nature conservation paradigms of protecting nature from human influence. However, it remains to be seen whether rewilding advocates can realise their ambitions to popularise and create peopled wild spaces across Britain's landscapes
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