• Microsatellites for microbiologists

      Sweet, Michael J.; Scriven, Lucinda A.; Singleton, Ian (2012)
      Microsatellites are repeating sequences of 2–6 base pairs of DNA. Currently, they are used as molecular markers in many organisms, specifically in genetic studies analyzing kinship and population structure. In addition, they can be used to study gene duplication and/or deletion. Although they are used in studies on microorganisms including fungi, bacteria, protists, and archaea, it appears that these genetic markers are not being utilized to their full microbiological potential. Microsatellites have many advantages over other genetic markers currently in use as they are in general species specific, and therefore, cross-contamination by nontarget organisms is rare. Furthermore, microsatellites are suitable for use with fast and cheap DNA extraction methods, with ancient DNA or DNA from hair and fecal samples used in noninvasive sampling, making them widely available as a genetic marker. Microsatellites have already proven to be a useful tool for evolutionary studies of pathogenic microorganisms such as Candida albicans and Helicobacter pylori, and the onset of new sequencing techniques (such as 454, PACBIO, and mini-ion sequencing) means the ability to detect such markers will become less time consuming and cheaper, thus further expanding their potential to answer important microbial ecology questions.
    • Migration

      Huck, Maren; University of Derby; University of Derby; United Kingdom (Wiley, 2017-04)
      Primate societies are not static. Group composition changes due to births and deaths, and also by emigration and immigration of individuals between different groups. These transfers, while considered costly for the individual, have important implications for the individual itself and the population as a whole. While, generally speaking, dispersal is male-biased in strepsirrhine and catarrhine primates and female-biased in platyrrhines, variations even between different populations of the same species become increasingly apparent. This indicates that dispersal is a conditional strategy that depends on numerous external and internal proximate factors, as well as individual cost–benefit calculations. Although the advent of more advanced molecular techniques has started to provide more insights into dispersal patterns, the life of dispersing floaters remains a challenging topic, but is fundamental in order to not only understand the general behavioral ecology and evolution of a species but also help evaluate the viability of populations.
    • Mineralogical and geochemical characterisation of warm-water, shallow-marine glaucony from the Tertiary of the London Basin

      Huggett, Jennifer; Adetunji, Jacob; Longstaffe, Fred; Wray, David; Natural History Museum, London; University of Derby; University of Western Ontario; University of Greenwich (Mineralogical Society, 2017-11-27)
      Glaucony is present in the Palaeocene sediments of the London Basin, from the Thanet Sand Formation to the gravel beds at the base of the Lower Mottled Beds of the Reading Formation. The Upnor Formation glaucony is a rare example of formation in warm, shallow, brackish water and this, combined with the ready availability of fresh material from boreholes, make this study important in developing our understanding of this mineral. Glaucony comprises up to 50% of the Upnor Formation, a grey to green sandstone, of variable thickness and composition, which was deposited in a warm, shallow, marine to estuarine environment, ∼55.6–56.2 Ma. Using morphological criteria, X-ray diffraction data and K+ abundance, the Upnor glaucony may be defined as evolved. The underlying shallow marine Thanet Sand contains <5% of nascent to slightly evolved glaucony. The rare earth element (REE) data for the Upnor Formation suggest more than one source for the sediment from which the Upnor glaucony formed, while the Thanet REE data are consistent with a large detrital clay component. In the Upnor Formation, the large proportion of glaucony that occurs as granule fragments rather than whole granules, and the high-energy estuarine to shallow-marine environment of deposition, are indicative of reworking. The Upnor glaucony is inferred to be intraformationally reworked, rather than derived from the Thanet Sand Formation. The glaucony may have formed in sediments deposited away from the main estuarine channel, and been subsequently reworked into higher-energy sediments. Warm seas with freshwater mixing are more typically characteristic of verdine formation than of glaucony. The shallow, brackish environment of deposition suggests that there is not a clear distinction between the environmental requirements of verdine (or odinite) and glaucony (or glauconite), as is often proposed. The highly fractured, delicate nature of some granules indicates that they have experienced some maturation in situ, after reworking. The oxygen and hydrogen isotopic compositions of Upnor Formation shark teeth and glaucony point to formation in low-salinity water at ∼23 ± 3°C, also consistent with formation in the Upnor Formation, rather than in a fully marine sediment and subsequent reworking. A higher than normal temperature of formation may have increased the rate of evolution of glaucony. Our multidisciplinary study considers many of the factors relating to depositional environment that must be considered when glaucony-rich facies are encountered in comparable palaeo-environmental settings elsewhere in the geological record.
    • Minimum drift times infer trajectories of ghost nets found in the Maldives

      Stelfox, Martin; Lett, Christophe; Reid, Geraldine; Souch, Graham; Sweet, Michael; University of Derby; Olive Ridley Project, Bramhall, Stockport, Cheshire; MARBEC, IRD, Ifremer, Univ Montpellier, CNRS, Sète, France; National Museums Liverpool (Elsevier BV, 2020-03-07)
      This study explores methods to estimate minimum drift times of ghost nets found in the Maldives with the aim of identifying a putative origin. We highlight that percentage cover of biofouling organisms and capitulum length of Lepas anatifera are two methods that provide these estimates. Eight ghost nets were collected in the Maldives and estimated drift times ranged between 7.5 and 101 days. Additionally, Lagrangian simulations identified drift trajectories of 326 historical ghost nets records. Purse seine fisheries (associated with Korea, Mauritius, the Philippines, Spain, France and Seychelles) and gill nets from Sri Lanka were identified as 'high risk' fisheries with regard to likley origins of ghost nets drifting into the Maldives. These fisheries are active in areas where dense particle clusters occured (drift trajectories between 30 and 120 days). Interestingly, ghost nets drifting less than 30 days however, remained inside the exclusive economic zone of the Maldivian archipelago highlighting potential illegal, unreported and unregulated fishing activity is occuring in this area. This study therefore points to the urgent need for gear loss reporting to be undertaken, especially by purse seine and gill net fisheries in order to ascertain the source of this major threat to marine life. This should also be coupled with an improvment in the data focused on spatial distribution of the abandoned, lost or discarded fishing gear originating from both large- and small-scale fisheries.
    • Modelling the impact of vaccination on tuberculosis in badgers.

      Hardstaff, Joanne L.; Bulling, Mark T.; Marion, Glenn; Hutchings, Michael R.; White, Piran C. L.; University of York, Environment Department (2013-04-10)
      SUMMARY Tuberculosis (TB) in livestock, caused by Mycobacterium bovis, persists in many countries. In the UK and Ireland, efforts to control TB through culling of badgers (Meles meles), the principal wildlife host, have failed and there is significant interest in vaccination of badgers as an alternative or complementary strategy. Using a simulation model, we show that where TB is self-contained within the badger population and there are no external sources of infection, limited-duration vaccination at a high level of efficacy can reduce or even eradicate TB from the badger population. However, where sources of external infection persist, benefits in TB reduction in badgers can only be achieved by ongoing, annual vaccination. Vaccination is likely to be most effective as part of an integrated disease management strategy incorporating a number of different approaches across the entire host community.
    • Molecular changes in skin pigmented lesions of the coral trout Plectropomus leopardus.

      Lerebours, Adélaïde; Chapman, Emma C.; Sweet, Michael J.; Heupel, Michelle R.; Rotchell, Jeanette M.; University of Hull; University of Derby; Australian Institute of Marine Science; James Cook University (Elsevier, 2016-07-28)
      A high prevalence of skin pigmented lesions of 15% was recently reported in coral trout Plectropomus leopardus, a commercially important marine fish, inhabiting the Great Barrier Reef. Herein, fish were sampled at two offshore sites, characterised by high and low lesion prevalence. A transcriptomic approach using the suppressive subtractive hybridisation (SSH) method was used to analyse the differentially expressed genes between lesion and normal skin samples. Transcriptional changes of 14 genes were observed in lesion samples relative to normal skin samples. These targeted genes encoded for specific proteins which are involved in general cell function but also in different stages disrupted during the tumourigenesis process of other organisms, such as cell cycling, cell proliferation, skeletal organisation and cell migration. The results highlight transcripts that are associated with the lesion occurrence, contributing to a better understanding of the molecular aetiology of this coral trout skin disease.
    • Molecular identification of papillomavirus in ducks

      Williams, Richard; Tolf, Conny; Waldenström, Jonas; Linnaeus University (Nature Research, 2018-06-14)
      Papillomaviruses infect many vertebrates, including birds. Persistent infections by some strains can cause malignant proliferation of cells (i.e. cancer), though more typically infections cause benign tumours, or may be completely subclinical. Sometimes extensive, persistent tumours are recorded– notably in chaffinches and humans. In 2016, a novel papillomavirus genotype was characterized from a duck faecal microbiome, in Bhopal, India; the sixth papillomavirus genotype from birds. Prompted by this finding, we screened 160 cloacal swabs and 968 faecal samples collected from 299 ducks sampled at Ottenby Bird Observatory, Sweden in 2015, using a newly designed real-time PCR. Twenty one samples (1.9%) from six individuals (2%) were positive. Eighteen sequences were identical to the published genotype, duck papillomavirus 1. One additional novel genotype was recovered from three samples. Both genotypes were recovered from a wild strain domestic mallard that was infected for more than 60 days with each genotype. All positive individuals were adult (P = 0.004). Significantly more positive samples were detected from swabs than faecal samples (P < 0.0001). Sample type data suggests transmission may be via direct contact, and only infrequently, via the oral-faecal route. Infection in only adult birds supports the hypothesis that this virus is sexually transmitted, though more work is required to verify this.
    • New disease outbreak affects two dominant sea urchin species associated with Australian temperate reefs

      Sweet, Michael J.; Bulling, Mark T.; Williamson, Jane E.; University of Derby (2016-06-09)
      Diseases of sea urchins have been implicated in dramatic transitions of marine ecosystems. Although no definitive causal agent has been found for many of these outbreaks, mostare hypothesised to be waterborne and bacterial. Here we show the first report of a novel diseaseaffecting at least 2 species of urchins off the south-eastern coast of Australia. The aetiologicalagent, identified via a range of molecular techniques, immuno-histology and inoculation experi-ments, was found to be the opportunistic pathogen Vibrio anguillarum . The disease appears to betemperature-dependent, with a faster transmission rate and increase in prevalence during ex -perimental trials conducted at higher temperatures. Furthermore, analysis of long-term field datasuggests that it may have already reached epidemic proportions. With the increases in ocean temperatures brought about by climate change, this novel urchin disease may pose a severe problem for the organisms associated with the temperate reefs off Australia and/or the ecosystemas a whole.
    • No single model for super-sized eruptions and their magma bodies

      Wilson, Colin J. N.; Cooper, George F; Chamberlain, Katy; Barker, Simon J; Myers, Madison L.; Illsley-Kemp, Finnigan; Farrell, Jamie; Victoria University of Wellington; Cardiff University; University of Derby; et al. (Nature, 2021-07-27)
      The largest explosive volcanic eruptions on Earth (‘supereruptions’) generate widespread ash-fall blankets and voluminous ignimbrites with accompanying caldera collapse. However, the mechanisms of generation, storage and evacuation of the parental silicic magma bodies remain controversial. In this Review, we synthesise field and laboratory evidence from Quaternary supereruptions to illustrate the great diversity in these phenomena. Despite their size, some supereruptions started mildly over weeks to months before escalating into climactic activity, whereas others went into vigorous activity immediately. Some eruptions occupied days or weeks, and others were prolonged over decades. Some were sourced from single bodies of magma, and others from multiple magma bodies that were simultaneously or sequentially tapped. In all cases the crystal-richer, deeper roots (>10 km) of the magmatic systems had lifetimes of tens to hundreds of thousands of years or more. In contrast, the erupted magmas were assembled at shallower depths (4-10 km) on shorter timescales, sometimes only centuries. Geological knowledge of past events, combined with modern geophysical techniques, demonstrates how large silicic caldera volcanoes (with past supereruptions) operate today. Future research is needed particularly on the processes behind modern volcanic unrest and the signals that might herald an impending eruption, regardless of size, at such volcanoes.
    • A novel approach to assess resilience of energy systems

      Matzenberger, Julian; Hargreave, Nigel; Raha, Debadayita; Das, Priyan; Vienna University of Technology, A-1040 Wien, Austria; Brunel University, Uxbridge; University of Nottingham; University of Moratuwa, Moratuwa, Sri Lanka (Emerald Publishing, 2015-06-08)
      The paper presents a brief history of the development of operations management (OM). This provides the backdrop for a content analysis of journal articles published in the Journal of Operations Management and the International Journal of Operations & Production Management between January 1990 and June 2003. MBA student survey data are then used to explore any gaps that may exist between the focus of academic research and the perceived importance of given OM subject areas to practitioners. The practical and conceptual insights highlighted are then used as the basis for a discussion of extant research priorities. The paper concludes with a preliminary conceptual framework that distinguishes between OM research seeking to consolidate operations practice and that which seeks to apply theoretical concepts into a practical context.
    • A novel investigation of a blister-like syndrome in aquarium echinopora lamellosa

      Smith, David; Leary, Peter; Bendall, Mark; Flach, Edmund; Jones, Rachel; Sweet, Michael J.; University of Derby (2014-05-14)
      This study investigates potential causes of a novel blister-like syndrome in the plating coral Echinopora lamellosa. Visual inspections of this novel coral syndrome showed no obvious signs of macroparasites and the blisters themselves manifested as fluid-filled sacs on the surface of the coral, which rose from the coenosarc between the coral polyps. Histological analysis of the blisters showed that there was no associated necrosis with the epidermal or gastrodermal tissues. The only difference between blistered areas and apparently healthy tissues was the presence of proliferated growth (possible mucosal cell hyperplasia) directly at the blister interface (area between where the edge of the blister joined apparently healthy tissue).No bacterial aggregates were identified in any histological samples, nor any sign of tissue necrosis identified. We conclude, that the blister formations are not apparently caused by a specific microbial infection, but instead may be the result of irritation following growth anomalies of the epidermis. However, future work should be conducted to search for other potential casual agents, including viruses
    • A novel sponge disease caused by a consortium of micro-organisms

      Sweet, Michael J.; Bulling, Mark T.; Cerrano, Carlo; University of Derby (2015-03-20)
      In healthy sponges, microbes have been shown to account for up to 40 % of tissues. The majority of these are thought to originate from survivors evading digestion and immune responses of the sponge and growing and residing in the microenvironments of the mesophyll. Although a large percentage of these microbes are likely commensals, they may also include potentially pathogenic agents, which under specific conditions, such as temperature stress, may cause disease. Here we report a novel disease (sponge necrosis syndrome) that is severely affecting populations of the sponge Callyspongia (Euplacella) aff biru. Both ITS fungal and 16S rDNA bacterial diversities were assessed in healthy and diseased individuals, highlighting six potential primary causal agents for this new disease: two bacteria, a Rhodobacteraceae sp. and a cyanobacterium, Hormoscilla spongeliae (formally identified as Oscillatoria spongeliae), and four fungi, a Ascomycota sp., a Pleosporales sp., a Rhabdocline sp., and a Clasosporium sp. Furthermore, histological analysis showed the dominance of fungal hyphae rather than bacteria throughout the disease lesion, which was absent or rare in healthy tissues. Inoculation trails showed that only a combination of one bacterium and one fungus could replicate the disease, fulfilling Henle–Koch’s postulates and showing that this sponge disease is caused by a poly-microbial consortium.
    • Nutrient deficiencies and the restriction of compensatory mechanisms in copepods

      Burian, Alfred; Grosse, Julia; Winder, Monika; Boschker, Henricus T.S.; Stockholm University; Utrecht University (British Ecological Society, 2017-11-14)
      The flexible regulation of feeding behaviour and nutrient metabolism is a prerequisite for consumers to grow and survive under variable food conditions. Thus, it is essential to understand the ecological trade-offs that restrict regulatory mechanisms in consumers to evaluate the consequences of nutrient limitations for trophic interactions. Here, we assessed behavioural and physiological adjustments to nutrient deficiencies in copepods and examined whether energy limitation, food digestibility or co-limitation with a second nutrient restricted compensatory mechanisms. A combination of C-13-labelling and compound-specific stable isotope measurements revealed that copepods compensated nitrogen deficiencies by raising retention efficiencies of amino acids (AA). The costs of higher retention efficiencies were reflected in the doubling of structural fatty acids (FA), probably required for morphological adaptations of the gut. A depletion of highly unsaturated FA in storage lipids and their selective retention suggested that these FA became co-limiting and restricted a further increase in AA retention efficiencies. Copepods feeding on phosphorus-limited algae showed a marked increase in ingestion rates but were not fully able to compensate dietary deficiencies. The increase in ingestion rates was thereby not restricted by higher foraging costs because energy storage in copepods increased. Instead, thicker cell walls of nutrient-limited algae indicated that algal digestion resistance restricted the extent of surplus feeding. The strongly nutrient-specific response of copepods had large implications for recycling rates, growth efficiencies and the potential top-down control at the plant-animal interface. Compensatory mechanisms to mitigate nutrient deficiencies are therefore an essential aspect of trophic interactions and have the potential to alter the structure of food web.
    • Of apples and oranges? The evolution of “monogamy” in non-human primates

      Huck, Maren; Di Fore, Anthony; Fernandez-Duque, Eduardo; University of Derby, Environmental Sustainability Research Centre; University of Texas at Austin; Yale University (Frontiers, 2020-01-10)
      Behavioral ecologists, evolutionary biologists, and anthropologists have been long fascinated by the existence of “monogamy” in the animal kingdom. Multiple studies have explored the factors underlying its evolution and maintenance, sometimes with contradicting and contentious conclusions. These studies have been plagued by a persistent use of fuzzy terminology that often leads to researchers comparing “apples with oranges” (e.g., comparing a grouping pattern or social organization with a sexual or genetic mating system). In this review, we provide an overview of research on “monogamy” in mammals generally and primates in particular, and we discuss a number of problems that complicate comparative attempts to understand this issue. We first highlight why the muddled terminology has hindered our understanding of both a rare social organization and a rare mating system. Then, following a short overview of the main hypotheses explaining the evolution of pair-living and sexualmonogamy, we critically discuss various claims about the principal drivers of “monogamy” that have been made in several recent comparative studies.We stress the importance of using only high quality and comparable data. We then propose that a productive way to frame and dissect the different components of pair-living and sexual or genetic monogamy is by considering the behavioral and evolutionary implications of those components from the perspectives of all participants in a species’ social system. In particular, we highlight the importance of integrating the perspective of “floater” individuals and considering their impacts on local operational sex ratios, competition, and variance in reproductive success across a population. We stress that pair-living need not imply a reduced importance of intrasexual mate competition, a situation that may have implications for the sexual selection potential that have not yet been fully explored. Finally, we note that there is no reason to assume that different taxa and lineages, even within the same radiation, should follow the same pathway to or share a unifying evolutionary explanation for “monogamy”. The study of the evolution of pair-living, sexual monogamy, and genetic monogamy remains a challenging and exciting area of research.
    • On the importance of the microbiome and pathobiome in coral health and disease

      Sweet, Michael J.; Bulling, Mark T.; University of Derby (Frontiers, 2017-01-20)
      The term “microbiome” was first coined in 1988 and given the definition of a characteristic microbial community occupying a reasonably well defined habitat which has distinct physio-chemical properties. A more recent term has also emerged, taking this one step further and focusing on diseases in host organisms. The “pathobiome” breaks down the concept of “one pathogen = one disease” and highlights the role of the microbiome, more specifically certain members within the microbiome, in causing pathogenesis. The development of next generation sequencing has allowed large data sets to be amassed describing the microbial communities of many organisms and the field of coral biology is no exception. However, the choices made in the analytical process and the interpretation of these data can significantly affect the outcome and the overall conclusions drawn. In this review we explore the implications of these difficulties, as well as highlighting analytical tools developed in other research fields (such as network analysis) which hold substantial potential in helping to develop a deeper understanding of the role of the microbiome in disease in corals. We also make the case that standardization of methods will substantially improve the collective gain in knowledge across research groups.
    • Ontogeny of juvenile freshwater pearl mussels, Margaritifera margaritifera (Bivalvia: Margaritiferidae).

      Lavictoire, Louise; Ramsey, Andrew; Moorkens, Evelyn; Souch, Graham; Barnhart, M. Christopher; University of Cumbria; University of Derby; Trinity College Dublin; Missouri State University (Public Library of Science (PLOS), 2018-03-28)
      The gills of juvenile freshwater bivalves undergo a complex morphogenesis that may correlate with changes in feeding ecology, but ontogenic studies on juvenile mussels are rare. Scanning electron microscopy was used to examine the ultrastructure and ontogeny of 117 juvenile freshwater pearl mussels (Margaritifera margaritifera) ranging in age from 1–44 months and length from 0.49–8.90 mm. Three stages of gill development are described. In Stage 1 (5–9 inner demibranch filaments), only unreflected inner demibranch filaments were present. In Stage 2 (9–17 inner demibranch filaments), inner demibranch filaments began to reflect when shell length exceeded 1.13 mm, at 13–16 months old. Reflection began in medial filaments and then proceeded anterior and posterior. In Stage 3 (28–94 inner demibranch filaments), outer demibranch filaments began developing at shell length > 3.1 mm and about 34 months of age. The oral groove on the inner demibranch was first observed in 34 month old specimens > 2.66 mm but was never observed on the outer demibranch. Shell length (R2 = 0.99) was a better predictor of developmental stage compared to age (R2 = 0.84). The full suite of gill ciliation was present on filaments in all stages. Interfilamentary distance averaged 31.3 μm and did not change with age (4–44 months) or with size (0.75–8.9 mm). Distance between laterofrontal cirri couplets averaged 1.54 μm and did not change significantly with size or age. Labial palp primordia were present in even the youngest individuals but ciliature became more diverse in more developed individuals. Information presented here is valuable to captive rearing programmes as it provides insight in to when juveniles may be particularly vulnerable to stressors due to specific ontogenic changes. The data are compared with two other recent studies of Margaritifera development.
    • Ophyiulus in Victoria: results of millipede surveys from south-eastern Australia

      Norton, Briony, A.; Thomson, Linda, J.; Nash; Michael A.; University of Sheffield; University of Melbourne (CSIRO, 2015-08-12)
      The composition and ecology of the millipede fauna of Victoria remain poorly understood. We collected millipedes as part of a series of ecological arthropod surveys across south-eastern Australia, focusing mainly on Victoria. These samples almost exclusively contained millipedes from the introduced order Julida. We pursued species identification of the julids when it became apparent there were species other than the well-recorded Ommatoiulus moreleti (Lucas, 1860) (Portuguese millipede) in the samples. The majority of specimens were O. moreleti, but we also detected at least one species of Cylindroiulus Verhoeff, 1894, as well as an Ophyiulus Berlese, 1884, species, specimens of which have been identified as Ophyiulus cf. targionii. These are the first Ophyiulus records for Victoria to our knowledge. We present preliminary data on the abundance through the year of Ophyiulus. This is the first study to examine this species in Victoria and little is currently known about its likely impact on agriculture or on native species. Monitoring and research of the species in the future is therefore warranted.
    • Opinions of small and medium UK construction companies on environmental management systems

      Bailey, Matthew; Booth, Colin A; Horry, Rosemary; Vidalakis, Christos; Mahamadu, Abdul-Majeed; Awuah, Kwasi Gyau Baffour; University of Derby; University of the West of England; University of Salford (Thomas Telford Ltd, 2021-02-16)
      Pressure to reduce the environmental impact of construction activities has increased, such that a paradigm shift is required. This paper presents stakeholder opinions of environmental management systems as a means for the construction industry to respond to these issues. Using a previous approach, the views of small and medium construction companies were sought, using questionnaires to ask respondents to reveal their perceived benefits of and barriers to implementing the ISO 14000 suite of environmental management standards in the UK. Detailed statistical analysis showed that environmental management systems can sometimes produce quantifiable benefits to organisations in terms of cost reduction. However, from a contractor’s view, the greatest benefit was a reduction in environmental impact outweighing financial benefits. Findings also demonstrated numerous barriers to an organisation exist, both internal and external, regarding adoption and use of environmental management systems. The most critical barrier was that cost savings do not always balance with the expense of implementation. Furthermore, waste minimisation at the design stage is viewed as most important. In general, the opinions gauged in this study indicated that short-term profits are normally considered more imperative than long-term gains. Therefore, despite a need to focus on developing strategies for removing or reducing the challenges of environmental management systems, the reality is that they may not be the panacea to sustainable development, as is often touted.
    • Optimization of water content for the cryopreservation of allium sativum In vitro cultures by encapsulation-dehydration

      Lynch, Paul; Souch, Graham; Zamecnik, Jiri; Harding, Keith; University of Derby (CryoLetters, 2016-10)
      BACKGROUND: There is a general requirement to determine and correlate water content to viability for the standardization of conservation protocols to facilitate effective cryostorage of plant germplasm. OBJECTIVE: This study examined water content as a critical factor to optimize the cryostorage of Allium sativum. MATERIALS AND METHODS: Stem discs were excised from post-harvest, stored bulbs prior to cryopreservation by encapsulation-dehydration and water content was determined gravimetrically. RESULTS: Survival of cryopreserved stem discs was 42.5%, with 22.5% exhibiting shoot regrowth following 6 h desiccation. Gravimetric data demonstrated a correlation between water content corresponding with survival / regrowth from desiccated, cryopreserved stem discs. For encapsulated stem discs a 25% residual moisture and corresponding water content of 0.36 g H2O g-1 d.wt correlated with maximal survival following ~6.5 h of desiccation. CONCLUSION: The data concurs with the literature suggesting the formation of a stable vitrified state and a ‘window’ for optimal survival and regrowth that is between 6 – 10 h desiccation. Further studies using differential scanning calorimetry (DSC) are suggested to substantiate these findings
    • Oxygen and carbon isotopic composition of Quaternary meteoric carbonates from western and southern Europe: their role in palaoenvironmental reconstruction

      Candy, I.; Adamson, K.; Gallant, C.E.; Whitfield, E.; Pope, Richard J. J.; University of Manchester; University of London, Royal Holloway; Liverpool John Moores University; University of Derby (2013-05-20)
      The relationship between environmental conditions and the δ18O and δ13C values of soil and groundwater carbonates in Europe is poorly understood. Consequently, the use of the isotopic composition of these carbonate palaeoclimatic indicators in European sedimentary sequences is restricted. In this study we examine the δ18O and δ13C values of soil and groundwater carbonates from western and southern Europe. In western Europe there is no relationship between carbonate δ18O values and carbonate δ13C values. The δ18O values of soil carbonate appears to be driven by temperature, whilst the δ13C value of soil and groundwater carbonate reflects the persistent dominance of C3 vegetation in this region during the Quaternary. The δ18O and δ13C values of soil carbonates from Spain and Crete show a strong degree of co-variance suggesting that they are being controlled by the same environmental factor. This is suggested to be aridity. δ18O values are controlled by soil moisture evaporation whilst δ13C value is controlled by soil moisture degassing, vegetation abundance and possible C3/C4 vegetation inputs. The paper concludes by highlighting the fact that, although currently under-utilised, the δ18O and δ13C values of soil and groundwater carbonates have a huge potential for providing important palaeoenvironmental information from sites across Europe.