• Investigations on Sanday. Vol 2. Tofts Ness: An island landscape through 3000 years of Prehistory Orcadian

      Dockrill, Stephen J.; Bond, Julie M.; Nicholson, R.A.; Smith, A.N. (2007)
      Tofts Ness is a peninsula at the north end of the Orcadian island of Sanday where mounds and banks represent a domestic landscape, marginal even in island terms, together with a funerary landscape. A combination of selective excavation and geophysical survey during 1985-8 revealed settlement and cultivation spanning Neolithic to Early Iron Age times, including burnt mounds and traces of plough cultivation. The Neolithic inhabitants of Tofts Ness appear not to have used either Grooved Ware or Unstan Ware, and it is suggested that this reflects a lack of status compared to the settlement at Pool. Instead, the pottery shares important links to contemporary assemblages from West Mainland Shetland, and this is echoed by the steatite artefacts. The link with Shetland remains visible into the Late Bronze Age. The upper levels of the main settlement mound contained the remains of stone-built roundhouses of the Late Bronze Age and Early Iron Age, of which the last survived to a height of 1.5m. A lack of personal items amongst the artefact assemblage again indicates the low status of the inhabitants. The economic evidence for all periods shows a mixed subsistence economy based on animal husbandry and barley cultivation, together with fishing, fowling and the exploitation of wild plants both terrestrial and marine. Important studies on the farming methods employed on Tofts Ness reveal a manuring strategy in managing small fields that was more akin to intensive gardening than field cultivation and a deliberate policy of harvesting the barley crop whilst under-ripe.
    • Inward rectifier potassium current (IK1) and Kir2 composition of the zebrafish (Danio rerio) heart

      Hassinen, M.; Haverinen, J.; Hardy, Matthew E.; Sheils, H.A.; Vornanen, M. (2015-12)
      Electrophysiological properties and molecular background of the zebrafish (Danio rerio) cardiac inward rectifier current (IK1) were examined. Ventricular myocytes of zebrafish have a robust (−6.7±1.2 pA pF−1 at −120 mV) strongly rectifying and Ba2+-sensitive (IC50=3.8 μM) IK1. Transcripts of six Kir2 channels (drKir2.1a, drKir2.1b, drKir2.2a, drKir2.2b, drKir2.3, and drKir2.4) were expressed in the zebrafish heart. drKir2.4 and drKir2.2a were the dominant isoforms in both the ventricle (92.9±1.5 and 6.3±1.5 %) and the atrium (28.9±2.9 and 64.7±3.0 %). The remaining four channels comprised together less than 1 and 7 % of the total transcripts in ventricle and atrium, respectively. The four main gene products (drKir2.1a, drKir2.2a, drKir2.2b, drKir2.4) were cloned, sequenced, and expressed in HEK cells for electrophysiological characterization. drKir2.1a was the most weakly rectifying (passed more outward current) and drKir2.2b the most strongly rectifying (passed less outward current) channel, whilst drKir2.2a and drKir2.4 were intermediate between the two. In regard to sensitivity to Ba2+ block, drKir2.4 was the most sensitive (IC50=1.8 μM) and drKir2.1a the least sensitive channel (IC50=132 μM). These findings indicate that the Kir2 isoform composition of the zebrafish heart markedly differs from that of mammalian hearts. Furthermore orthologous Kir2 channels (Kir2.1 and Kir2.4) of zebrafish and mammals show striking differences in Ba2+- sensitivity. Structural and functional differences needs to be taken into account when zebrafish is used as a model for human cardiac electrophysiology, cardiac diseases, and in screening cardioactive substances.
    • Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia) shell calcite precipitated at constant temperature.

      Clarke, Leon J.; Kennedy, H.A.; Richardson, C.A.; Freitas, P.S. (2009)
      Small-scale heterogeneity of biogenic carbonate elemental composition can be a significant source of error in the accurate use of element/Ca ratios as geochemical proxies. In this study ion microprobe (SIMS) profiles showed significant small-scale variability of Mg/Ca, Sr/Ca and Mn/Ca ratios in new shell calcite of the marine bivalves Pecten maximus and Mytilus edulis that was precipitated during a constant-temperature culturing experiment. Elevated Mg/Ca, Sr/Ca and Mn/Ca ratios were found to be associated with the deposition of elaborate shell features, i.e. a shell surface stria in P. maximus and surface shell disturbance marks in both species, the latter a common occurrence in bivalve shells. In both species the observed small-scale elemental heterogeneity most likely was not controlled by variable transport of ions to the extra-pallial fluid, but by factors such as the influence of shell organic content and/or crystal size and orientation, the latter reflecting conditions at the shell crystalsolution interface. In the mid and innermost regions of the P. maximus shell the lack of significant small-scale variation of Mg/Ca ratios, which is consistent with growth at constant temperature, suggest a potential application as a palaeotemperature proxy. Cross-growth band element/Ca ratio profiles in the interior of bivalve shells may provide more promising palaeo-environmental tools than sampling from the outer region of bivalve shells.
    • The ionic liquid ethyltri-n-butylphosphonium tosylate as solvent for the acid-catalysed hetero-Michael reaction.

      Karodia, Nazira; Liu, Xihan; Ludley, Petra; Pletsas, Dimitrios; Stevenson, Grace (2006)
      A new and convenient method for the acid-catalysed Michael addition reactions of alcohols, thiols and amines to methyl vinyl ketone has been developed using the ionic liquid ethyltri-n-butylphosphonium tosylate. The reaction conditions are mild and obviate the need for toxic and expensive Lewis acid catalysts, offering advantages over more commonly used systems.
    • Iontophoretic estradiol skin delivery and tritium exchange in ultradeformable liposomes

      Bonner, Michael C.; Barry, Brian W.; Essa, Ebtessam A. (2002)
      This work evaluated the in vitro transdermal iontophoretic delivery of tritiated estradiol from ultradeformable liposomes compared with saturated aqueous solution (control). Effects of current density and application time on tritium exchange with water were also determined. Penetration studies used three Protocols. Protocol I involved occluded passive steady state estradiol penetration from ultradeformable liposomes and control. The effect of current densities on drug penetration rates was also assessed (Protocol II). In Protocol III, three consecutive stages of drug penetration (first passive, iontophoresis and second passive) through the same human epidermal membranes were monitored. Such an experimental design investigated the possible effect of high current density (0.8 mA/cm2) on skin integrity. The tritium exchange study showed that extent of exchange correlated well with current density and time of application, with some shielding of estradiol by the liposomal structure. Liposomes enhanced estradiol passive penetration after occlusion. Protocol II showed that estradiol flux increased linearly with current density, although being delivered against electroosmotic flow. In Protocol III, reduction in flux of the second passive stage to near that of the first reflected a reversibility of the structural changes induced in skin by current.
    • Irish-Scottish connections in the 1st millennium AD: an evaluation of the links between souterrain ware and Hebridean ceramics

      Armit, Ian (2008)
      Although some limited consideration has been given to the possibility of links between the early medieval ceramic traditions of the Western Isles and the souterrain ware of north-east Ireland, these have tended to be framed in the context of supposed Dalriadic cultural infl uence fl owing from Ireland to Scotland. A re-evaluation of the possible relationships between these pottery styles suggests that souterrain ware might instead be seen as part of a regional expansion of western Scottish pottery styles in the seventh¿eighth centuries AD. This raises the question of what social processes might underlie the cross-regional patterning evident in what remains a vernacular, rather than a high-status, technology.
    • Is it assessment of learning or assessment for learning?

      Rahman, Sayeeda; Majumder, Md A.A. (2014)
      Assessment is a central feature of teaching and the curriculum. It powerfully frames how students learn and what students achieve. It is one of the most significant influences on students’ experience of higher education and all that they gain from it. The reason for an explicit focus on improving assessment practice is the huge impact it has on the quality of learning’.1 ‘Students should realize that assessment can be an opportunity for learning, rather than just something to be endured and suffered’.2 'Institutions should ensure that appropriate feedback is provided to students on assessed work in a way that promotes learning and facilitates improvement'.3
    • Is the ability to identify deviations in multiple trajectories compromised by amblyopia?

      Tripathy, Srimant P.; Levi, D.M. (2006)
      Amblyopia results in a severe loss of positional information and in the ability to accurately enumerate objects (V. Sharma, D. M. Levi, & S. A. Klein, 2000). In this study, we asked whether amblyopia also disrupts the ability to track a near-threshold change in the trajectory of a single target amongst multiple similar potential targets. In the first experiment, we examined the precision for detecting a deviation in the linear motion trajectory of a dot by measuring deviation thresholds as a function of the number of moving trajectories (T). As in normal observers, we found that in both eyes of amblyopes, threshold increases steeply as T increases from 1 to 4. Surprisingly, for T = 1-4, thresholds were essentially identical in both eyes of the amblyopes and were similar to those of normal observers. In a second experiment, we measured the precision for detecting a deviation in the orientation of a static, bilinear "trajectory" by again measuring deviation thresholds (i.e., angle discrimination) as a function of the number of oriented line "trajectories" (T). Relative to the nonamblyopic eye, amblyopes show a marked threshold elevation for a static target when T = 1. However, thresholds increased with T with approximately the same slope as in their preferred eye and in the eyes of the normal controls. We conclude that while amblyopia disrupts static angle discrimination, amblyopic dynamic deviation detection thresholds are normal or very nearly so.
    • Is there a link between dizziness and vision? A systematic review

      Armstrong, Deborah; Charlesworth, Emily; Alderson, Alison J.; Elliott, David B. (2016-07)
      Purpose: The aim of this study was to systematically review the literature to investigate the link (if any) between vision and dizziness. Methods: Medline, CINAHL, AMED, Web of Science and The Cochrane Library were searched with keywords chosen to find articles which investigated the causes of dizziness and considered vision as a possible trigger. Citation chaining of all included papers was performed in addition to the hand searching of all reference lists. Unpublished literature was identified using www.opengrey.eu. The review considered studies involving adults which link, measure or attempt to improve any aspect of vision in relation to dizziness. Results: Nine thousand six hundred and eighty one possible references were found, and the abstracts were screened independently by two reviewers to determine if they should be included in the study. Thirteen papers were found which investigated whether dizziness was linked to an assessment of vision. Visual impairment measures were crude and typically self-report, or Snellen visual acuity with little or no measurement details. Five studies found an independent link between dizziness and vision, five found a weak association (typically finding a link when univariate analyses were used, but not when multivariate analyses were used), and three found no association. Studies finding a strong link were usually cross-sectional with a large study population whereas those finding a weak association had relatively small numbers of participants. Studies which did not find an association used a broad definition of dizziness that included the term light-headedness, an unreliable Rosenbaum near visual acuity chart or an unusual categorisation of visual acuity. Conclusions: This review suggests that dizziness (although likely not ‘light-headedness’) is linked with poor vision although further studies using more appropriate measures of vision are recommended.
    • Ischaemic skeletal muscle increases serum ischaemia modified albumin.

      Troxler, M.; Thompson, D.; Homer-Vanniasinkam, Shervanthi (2009-11-02)
      Objectives Ischaemia modified albumin (IMA) has been used as a marker of myocardial ischaemia but little is known about its production during ischaemia of other tissues. The clinical models of patients with intermittent claudication and major arterial surgery were used to investigate IMA production from ischaemic skeletal muscle. Materials and methods IMA was measured pre-operatively, at end ischaemia, and 5min, 4, 24, 48, 72 and 144h post-surgery in patients undergoing (a) revascularisation for intermittent claudication (IC, n=15), (b) abdominal aortic aneurysm repair (AAA, n=12) and controls (n=16). Results The median pre-operative IMA concentration in IC patients was significantly higher than the AAA group (88.3 versus 83.5U/ml, p=0.036) and controls (88.3 versus 80.3U/ml, p=0.031). IMA concentrations increased significantly during arterial clamping in both IC and AAA groups (88.3 versus 120.0U/ml, p=0.001; 83.5 versus 118.8U/ml, p=0.002, respectively) consistent with increased skeletal muscle ischaemia. In contrast, there was only a mild perioperative increase in the controls (80.3 versus 91.6U/ml, p=0.012). Conclusions Patients with intermittent claudication have significantly elevated IMA and skeletal muscle ischaemia during arterial surgery results in significantly increased circulating IMA. When IMA is used to detect myocardial ischaemia, ischaemic skeletal muscle must be excluded.
    • Isolation of stimulus characteristics contributing to Weber's law for position.

      Whitaker, David J.; Bradley, A.; Barrett, Brendan T.; McGraw, Paul V. (2002)
      To examine the independent contribution of various stimulus characteristics to positional judgements, we measured vernier alignment performance for three types of Gabor stimuli. In one, only the contrast envelope of the upper and lower stimulus elements was offset, with the luminance-modulated carrier grating remaining in alignment. In the second, only the carrier grating was offset. In the third, both carrier and envelope were offset together. Performance was examined over a range of element separations. When both cues are available, thresholds for small separations are dominated by carrier offset information and are inversely proportional to carrier frequency. At large separations, thresholds are governed by the spatial scale characteristics of the envelope. For broad-band stimuli such as lines, bars or dots typically used for vernier acuity, their higher frequency content can be used when separations are small, but as separation increases a smooth transition between the scales that determine threshold results in the continuum known as Weber's law for position. That is, with increasing separation, larger scales must be used, and thresholds increase in direct proportion to 1/frequency.
    • Isolation rearing impairs novel object recognition and attentional set shifting performance in female rats

      McLean, Samantha L.; Grayson, Ben; Harris, M.; Protheroe, C.; Bate, S.; Woolley, M.L.; Neill, Joanna C. (2010-01)
      It has been suggested that the isolation rearing paradigm models certain aspects of schizophrenia symptomatology. This study aimed to investigate whether isolation rearing impairs rats’ performance in two models of cognition: the novel object recognition (NOR) and attentional set-shifting tasks, tests of episodic memory and executive function, respectively. Two cohorts of female Hooded-Lister rats were used in these experiments. Animals were housed in social isolation or in groups of five from weaning, post-natal day 28. The first cohort was tested in the NOR test with inter-trial intervals (ITIs) of 1 min up to 6 h. The second cohort was trained and tested in the attentional set-shifting task. In the NOR test, isolates were only able to discriminate between the novel and familiar objects up to 1-h ITI, whereas socially reared animals remembered the familiar object up to a 4-h ITI. In the attentional set-shifting task, isolates were significantly and selectively impaired in the extra-dimensional shift phase of the task (P < 0.01). Rats reared in isolation show impaired episodic memory in the NOR task and reduced ability to shift attention between stimulus dimensions in the attentional set-shifting task. Because schizophrenic patients show similar deficits in performance in these cognitive domains, these data further support isolation rearing as a putative preclinical model of the cognitive deficits associated with schizophrenia.
    • Isomorphism: 'Molecular similarity to crystal structure similarity' in multicomponent forms of analgesic drugs tolfenamic and mefenamic acid

      Ranjan, S.; Devarapalli, R.; Kundu, S.; Saha, S.; Deolka, S.; Vangala, Venu R.; Reddy, C.M. (2020-03)
      The non-steroidal anti-inflammatory drugs mefenamic acid (MFA) and tolfenamic acid (TFA) have a close resemblance in their molecular scaffold, whereby a methyl group in MFA is substituted by a chloro group in TFA. The present study demonstrates the isomorphous nature of these compounds in a series of their multicomponent solids. Furthermore, the unique nature of MFA and TFA has been demonstrated while excavating their alternate solid forms in that, by varying the drug (MFA or TFA) to coformer [4-dimethylaminopyridine (DMAP)] stoichiometric ratio, both drugs have produced three different types of multicomponent crystals, viz. salt (1:1; API to coformer ratio), salt hydrate (1:1:1) and cocrystal salt (2:1). Interestingly, as anticipated from the close similarity of TFA and MFA structures, these multicomponent solids have shown an isomorphous relation. A thorough characterization and structural investigation of the new multicomponent forms of MFA and TFA revealed their similarity in terms of space group and structural packing with isomorphic nature among the pairs. Herein, the experimental results are generalized in a broader perspective for predictably identifying any possible new forms of comparable compounds by mapping their crystal structure landscapes. The utility of such an approach is evident from the identification of polymorph VI of TFA from hetero-seeding with isomorphous MFA form I from acetone–methanol (1:1) solution. That aside, a pseudopolymorph of TFA with dimethylformamide (DMF) was obtained, which also has some structural similarity to that of the solvate MFA:DMF. These new isostructural pairs are discussed in the context of solid form screening using structural landscape similarity
    • Isoniazid resistance levels of Mycobacterium tuberculosis can largely be predicted by high-confidence resistance-conferring mutations.

      Lempens, P.; Meehan, Conor J.; Vandelannoote, K.; Fissette, K.; de Rijk, P.; Van Deun, A.; Rigouts, L.; de Jong, B.C. (2018-02-19)
      The majority of Mycobacterium tuberculosis isolates resistant to isoniazid harbour a mutation in katG. Since these mutations cause a wide range of minimum inhibitory concentrations (MICs), largely below the serum level reached with higher dosing (15 mg/L upon 15–20 mg/kg), the drug might still remain partly active in presence of a katG mutation. We therefore investigated which genetic mutations predict the level of phenotypic isoniazid resistance in clinical M. tuberculosis isolates. To this end, the association between known and unknown isoniazid resistance-conferring mutations in whole genome sequences, and the isoniazid MICs of 176 isolates was examined. We found mostly moderate-level resistance characterized by a mode of 6.4 mg/L for the very common katG Ser315Thr mutation, and always very high MICs (≥19.2 mg/L) for the combination of katG Ser315Thr and inhA c-15t. Contrary to common belief, isolates harbouring inhA c-15t alone, partly also showed moderate-level resistance, particularly when combined with inhA Ser94Ala. No overt association between low-confidence or unknown mutations, except in katG, and isoniazid resistance (level) was found. Except for the rare katG deletion, line probe assay is thus not sufficiently accurate to predict the level of isoniazid resistance for a single mutation in katG or inhA.
    • Isotope analysis of incremental human dentine: towards higher temporal resolution

      Beaumont, Julia; Gledhill, Andrew R.; Montgomery, Janet (2014)
      Here we present a novel method which allows the measurement of the stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) from much smaller samples of dentine than previously possible without affecting the quality parameters. The reconstruction of the diet of past populations using isotopic analysis of bone collagen is a well-established tool. However, because of remodelling of bone throughout life, this gives a blurred picture of the diet. The analysis of δ13C and δ15N from tiny increments of dentine utilizes tissue that does not remodel and permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. This new method has been tested on archaeological teeth from two sites: three molar teeth from the 19th Century Kilkenny Union Workhouse Famine cemetery, Ireland; and three from the Anglian (5-7th centuries AD) cemetery at West Heslerton, Yorkshire, England, selected on the basis of their varied preservation. The methods of incremental dentine sectioning described in Beaumont et al (2013)[1] were carried out and a sub-section removed prior to denaturing and lyophilisation. The two sample sets, dentine and collagen from each section, were measured by isotope ratio mass spectrometry. The profiles produced from each of the six teeth studied show close correlation in isotope ratios indicating that demineralized dentine which has not been denatured and lyophilised produces isotope ratios comparable with dentine collagen. This finding allows analysis of extremely small samples of dentine which could previously not be measured using current instruments and methods.
    • Isotopic Evidence for Dietary Variability in the Early Hominin Paranthropus robustus

      Lee-Thorp, Julia A.; De Ruiter, D.; Passey, B.; Sponheimer, M.B. (2006)
      Traditional methods of dietary reconstruction do not allow the investigation of dietary variability within the lifetimes of individual hominins. However, laser ablation stable isotope analysis reveals that the ¿13C values of Paranthropus robustus individuals often changed seasonally and interannually. These data suggest that Paranthropus was not a dietary specialist and that by about 1.8 million years ago, savanna-based foods such as grasses or sedges or animals eating these foods made up an important but highly variable part of its diet.
    • An isotopic investigation into the origins and husbandry of Mid-Late Bronze Age cattle from Grimes Graves, Norfolk

      Towers, Jacqueline R.; Bond, Julie M.; Evans, J.; Mainland, Ingrid L.; Montgomery, Janet (2017-10)
      Bioarchaeological evidence suggests that the site of Grimes Graves, Norfolk, characterised by the remains of several hundred Late Neolithic flint mineshafts, was a permanently settled community with a mixed farming economy during the Mid-Late Bronze Age (c. 1400 BC – c. 800 BC). The aim of this study was to investigate, through isotope ratio analysis (87Sr/86Sr, δ13C and δ18O), the origins and husbandry of Bronze Age cattle (Bos taurus) excavated from a mineshaft known as the “1972 shaft”. Strontium isotope ratios from the molar enamel of ten Grimes Graves cattle were compared with eight modern animals from the Chillingham Wild White cattle herd, Northumberland. The range of 87Sr/86Sr values for the modern cattle with known restricted mobility was low (0.00062) while the values for the Grimes Graves cattle varied much more widely (range = 0.00357) and suggest that at least five of the cattle were not born locally. Two of these animals were likely to have originated at a distance of ≥ 150 km. Intra-tooth δ13C profiles for eight of the Grimes Graves cattle show higher δ13C values compared to those of Early Bronze Age cattle from central England. Most of these profiles also display pronounced shifts in δ13C during the period of enamel formation. One possible interpretation is that the cattle were subject to dietary change resulting from movement between habitats with different vegetation δ13C values. More comparative data, both archaeological and modern, is required to validate this interpretation. The multi-isotope approach employed in this study suggests that certain cattle husbandry and/or landscape management practices may have been widely adopted throughout central Britain during the Mid-Late Bronze Age.
    • Issues of trust, fairness and efficacy: a qualitative study of information provision for newly metered households in England.

      Knamiller, C.; Sharp, Liz (2009)
      There is widespread agreement among agencies governing UK water management that more extensive domestic water metering combined with additional measures will deliver a more efficient domestic water usage. This paper argues that qualitative research is needed to select and hone additional measures. According to theory, cooperation to reduce water use is more likely if people: a) believe in the necessity to reduce use; b) feel costs are fairly shared; and c) believe their actions can affect the situation. The case study of Lydd, Kent, is presented. Lydd is the first location in which compulsory water metering has been imposed in the UK. Qualitative information was collected to inform the communication strategies being implemented by the water supply company. The investigation found that none of the three factors predicted by theory were completely present. The paper concludes by providing some recommendations for improving the water company's communications strategy for encouraging a reduction in domestic water use. The key role of qualitative information in assisting in the targeting and design of water demand management programmes is highlighted.
    • Istres, Le Castellan

      Armit, Ian; Horsley, T.; Marty, F. (2008)
    • Istres, Vigne Gaste

      Armit, Ian; Thomas, N.; Marty, F. (2008)