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The nonlocal stress tensor is an indispensable constitutive equation required to close the thermodynamic system of nonlocal fluid dynamics. A nonlocal functional variational principle is employed to derive a general expression for the thermodynamically reversible stress tensor for a two-phase, single component, nonlocal fluid. The Euler–Lagrange equation and Noether’s current are used to obtain the general form of the stress tensor, which is then used to derive a wide range of functional forms found in the literature. We also clarify some existing ambiguities. The general form of the nonlocal stress tensor is able to represent micro scale intermolecular interactions, and provides an efficient mesoscale numerical tool for multi-scale analysis using Lattice Boltzmann simulation.

Summary The composition of forest litter and understorey layer, and fungal biomass (in terms of ergosterol) were measured in eight subplots over a winter – spring period (January to April). The sampling site was positioned in a range of woodland habitats (variously dominated by beech, Fagus sylvatica ; birch, Betula pendula × pubescens , and oak Quercus petraea ) and a clear area covered with grass (dominated by Holcus lanatus ). The results were analysed together with data on bacteria and microinvertebrates available from parallel research. Levels of ergosterol in individual subplots ranged between 50 and 160 µ g g − 1 DW. Fungal biomass decreased in March, and then increased signifi cantly in April. Stepwise regression models for ergosterol indicated positive relationships with moisture content (February), bacteria (all but February and March), fl agellates (February) and plant-feeding nematodes and fl ies (January, overall). The relationships with roots, seeds, the collective variable ‘ other microinvertebrates ’ (all March), amoebae (February) and fragments (March, overall) were negative, while the relationship between fungi- and microbial-feeding nematodes changed sign between February ( − ) and March (+). Results of analysis of covariance for fungal ergosterol were signifi cant only for January and the combined dataset. In January, fungi were shown to be signifi cantly related to amoebae, bacteria and a collembolan Folsomia candida , while the only signifi cant predictor returned by the overall model was bacteria. Correlation analysis confi rmed some effects already noted, and revealed a number of further interactions. The results highlighted the complexity of factors infl uencing temporal dynamics and spatial variability of

Abstract The micro and meso-invertebrate abundance was measured, together with forest litter composition, in eight plots of differing vegetation (dominated by beech and birch) over a winter-spring period. The litter moisture content was a mean of 76% during the sampling period and the beech sites were the driest. The results were analysed using a suite of statistical techniques, together with data on protozoa, fungi and bacteria available from parallel research. Nematodes were analysed according to the trophic levels, which included microbial feeders, plant feeders and predators. The majority of arthropods found were the collembolan, Folsomia candida and cryptostigmatid mites, with very small quantities of other micro- and mesoarthropods (such as larvae and mesostigmatid mites). The microarthropod populations peaked in January and fell during subsequent months, while population numbers of nematodes showed a decrease between January and February, followed by an increase in March. ANOVA showed a significant date effect, but no site-date interactions for the population abundance of both nematodes and microarthropods. Ecological interactions of meiofauna were analysed by ANCOVA, stepwise regression, and correlation analysis. Examples of relationships revealed include positive relationships of plant-feeding nematodes (PFN) with microbial feeding nematodes (MFN), and of F. candida with cryptostigmatid mites. Other positive interactions were found for PFN, MFN, F. candida, cryptostigmatid and mesostigmatid mites with litter components, such as beech leaves and litter thickness, moisture and grass, and protozoa. Negative interactions were recorded for PFN, MFN, F. candida, cryptostigmatid and mesostigmatid mites with beech leaves, fungi, protozoa and bacteria. The results have highlighted a very complex structure of factors influencing the temporal and spatial dynamics of the forest litter community. It is suggested that temperature and moisture content particularly influence the invertebrates present. The invertebrates appear to be present in a range of microhabitats, which may have resulted in a reduced level of competition and a high level of positive interactions revealed.

Since 1994 data on fungal fruiting have been gathered in the Dawyck Botanic Garden outside Edinburgh, including that for eight plots within a 7.5 ha wood, which has been left unmanaged in order to investigate relationships amongst fungal succession, habitat characteristics and local weather patterns. The climatic data are provided by a small meteorological station situated on site. To handle nearly 4000 entries of data so far collected a computer database was constructed. This assists querying of the information so that changes in fungal communities and patterns of succession can be observed, and the relevant data extracted for further analysis. To aid in this analysis, and to give the user full control over editing, updating and querying the database, a special computer program was compiled. Analysis of the database records revealed that the currently known Dawyck fungal community comprises over 620 different taxa, and the species list increases every year. Although some species of mycorrhizal fungi showed high specificity towards their preferred host either at species (e.g. Lactarius blennius with beech, Lactarius quietus with oak, Russula fellea and Russula mairei with beech), or at genus level (e.g. Suillus spp. with Pinaceae), some other common fungi (e.g. of the genus Amanita ) were found to have very wide host ranges. In addition, unusual mycorrhizal associations have also been recorded. A lime tree ( Tilia ), which is supposedly primarily endomycorrhizal, has been found regularly associated with Russula cyanoxantha , Russula parazurea , Russula pectinata and Inocybe fastigiata . Many common Scottish fungi were found to be associated with introduced exotic trees, which is illustrated on the example of Pseudotsuga menziesii (Douglas Fir). The software created utilises the Microsoft Office suite of programs. Microsoft Access was used to construct the database, and Microsoft Excel was used for statistical investigations. The software was programmed using Microsoft Visual Basic, and provided a means of extracting the necessary data stored in Access and controlling the formulae used in Excel for their analysis. The recorded seasonal patterns of fungal fruiting was successfully described by a simulation mathematical model comprising differential and algebraic equations. This model may now be used as a submodel within more complex models describing terrestrial ecosystem processes. Examples of model simulations and sensitivity analysis are given and implications for future research discussed.

Summary New Trichoderma isolates were prepared from soils collected in the areas of the world where the dry rot fungus Serpula lacrymans is indigenous. Agar-screening tests were carried out to identify the antagonistic effects of isolates and determine if their mode of action was geared towards production of volatiles. Overall, Trichoderma isolates from Northern California, USA, were found to be extremely effective against S. lacrymans (Schumacher ex Fr. Gray.) and some produced a killing effect in the agar systems. In addition, these isolates inhibited S. lacrymans growth by volatile production even in the absence of direct contact between the Trichoderma isolate and S. lacrymans, whereas a standard laboratory culture of Trichoderma harzianum T25 was found to be much less effective. In two different soil and wood microcosms the USA isolates were also able to stop the growth of S. lacrymans and produced an apparent killing effect.

A previous qualitative study [Nurse Education Today 20 (2000) 499] investigated perceptions of nurse teachers, student nurses and preceptors of the theory-practice gap said to exist within nursing. One theme was views of how the theory-practice gap could be closed. A subsequent quantitative study is reported here, in which this theme was translated into three factors. A full factorial experimental design was used to study the effect of these factors on theoretical knowledge and practical skill acquisition in a sample of first year undergraduate student nurses from one institution of higher education (n=19). The effect of whether a nurse teacher or preceptor taught students theoretical elements relating to a clinical specialty, whether the nurse teacher and preceptor collaborated on the content of what was taught to students and whether students went straight to, or delayed the clinical specialty following theoretical input, was examined. The results demonstrated preceptors were more effective than nurse teachers in promoting theoretical knowledge relating to their clinical specialty. Collaboration between the preceptors and nurse teachers on teaching content was ineffective at increasing theoretical knowledge. Delay between theoretical input and clinical experience was not detrimental for medical placements and for rehabilitation placements, resulted in an improved theoretical knowledge.

The abundance of heterotrophic flagellates, ciliates and naked amoebae was measured in 8 sites covered with different vegetation (beech, birch, beech-birch, birch-oak-beech, grass) from January to April 2001. The results were analysed by a suite of mathematical techniques, together with data on bacteria, fungi, nematodes, microarthropods, and the composition of forest litter and field layer, available from parallel research. The population levels ranged between 4.02 and 795 × 103, 28 and 1010, 35 and 1170 g–1 litter dry wt for flagellates, ciliates and amoebae, respectively. Temporal changes in the microbiota appeared to be affected by progressive winter cooling followed by a spring increase in temperature, and influenced by habitat characteristics and a complex multivariate interplay among ecosystem components. The population abundance in winter (January-mid March) was higher than in spring (late March–April) for all protozoa. Amoebae showed minimum values in March, followed by considerable recovery in April. However, ciliate values dropped slightly between March and April, whilst flagellate values steadily decreased throughout the whole research period, suggesting that the spring growth of ciliates and flagellates might have been arrested by increased predation and/or competition. Statistical analysis revealed a number of significant relationships between the protozoa studied and other ecosystem components. These relationships were indicative of the conditions studied and may, therefore, be useful for future reference. The results highlighted the complexity of transient multivariate interactions of protobiota in forest litter, suggesting that any interpretations of the population dynamics must take account of a full range of both temporal and spatial factors.

According to Google Scholar, more than 1.6 million scholarly articles and book chapters have been published to date, which in one way or another describe “inter-disciplinary” research efforts. Many scientific periodicals, likeWater, Air and Soil Pollution, include the term inter-disciplinary in their full, official title, and their number is steadily growing. Likewise, more and more research institutes are devoted explicitly to interdisciplinary endeavors. This attractiveness of venues where several disciplines meet to address pressing research questions is perhaps nowhere clearer than in relation to environmental concerns. In most areas in this field, the research community is now confronted with issues of such a complexity and technical difficulty that they preclude simple treatments carried out entirely within the confines of individual disciplines, like environmental physics, chemistry, or microbiology. In the transformative research (Trevors et al. 2012) that is direly needed to address most cases of environmental contamination or the numerous problems arising at a variety of spatial scales because of global climate change, input from different disciplinary perspectives, including those of economics and social sciences, is increasingly recognized as essential. Many authors refer to research efforts involving several distinct disciplines as inter-disciplinary. Equally, many adopt alternate terms, e.g., multi-, pluri-, cross-, or trans-disciplinary, to describe what essentially appears to be the same thing. In some cases, the same terms are adopted to refer to very different concepts. For example, the term of “cross-disciplinarity” sometimes serves as an umbrella for multi-, inter-, and transdiciplinarity (e.g., Hinze 1999; Wu 2006), but occasionally is also used to designate research efforts that are very distinct in character from these “other”-disciplinarities. This profusion of terms has generated and continues to cause a great deal of confusion in practice, in particular when participants in research efforts involving distinct disciplines have very different perceptions of what their roles should be. Similarly, discrepancies between the expectations of funding agencies, research institutions, program managers, and individual researchers about the level of disciplinary integration that should be targeted in any given inter-disciplinary effort can lead to utter confusion and may explain to some extent why so many of these efforts are reported to stumble or even fail altogether (e.g., Hicks et al. 2010; Water Air Soil Pollut (2014) 225:1997 DOI 10.1007/s11270-014-1997-7

Relationships between Serpula lacrymans and S. himantioides isolates of ‘wild’ Himalayan woodland and building (European and Australian) origin were examined using RAPD-PCR and ITS rDNA sequence comparison. GelCompar analysis of the genetic fingerprints of eighteen isolates using four RAPD-primer combinations clearly distinguished S. lacrymans and S. himantioides. Little intraspecific variation was observed in S. lacrymans (including isolates of Himalayan woodland origin), relative to S. himantioides. Despite previously reported differences in growth rates and decay capabilities of ‘wild’ Himalayan woodland S. lacrymans isolates and those from buildings, RAPD fingerprints and ITS sequences indicated they were genetically similar. Interspecific ITS sequence polymorphisms were consistent with other studies and clearly demonstrated S. himantioides and S. lacrymans were distinct taxa. Evolutionary questions regarding the origins of S. lacrymans are discussed.

A full-scale model, containing numerous moisture sensors, was constructed to simulate the infection of the vulnerable floor-wall junction in a historic building by the dry rot fungus, Serpula lacrymans, and subsequent treatment by a chemical-free method. During the infection of the materials, growth of S. lacrymans became luxuriant throughout. Subsequent opening of the plaster walling of the construction, followed by aeration via ambient humidity then by fan drying, caused all exposed growth to become shrivelled and inactivated. Conversely, growth of S. lacrymans into an enclosed lower chamber, below the level of the flooring, was stimulated by the treatments. This latter growth, which emerged mostly from the stone walling, responded rapidly to direct treatment by ambient humidity followed by fan drying; however the shrivelled mycelium vigorously recrudesced soon after the restoration of suitable environmental conditions. Removal of excess moisture from the system, or isolation of timber from damp masonry, prevented this recrudescence. The salient features of chemical-free treatment via air drying were therefore demonstrated in a controlled and representative manner.

The potential of immunological probes, viz. antisera, as specific detection systems for the basidiomycete organisms Lentinus lepideus (a major cause of distribution pole failure) and Coriolus versicolor have been investigated. Using immunodot-blot techniques semi¬quantitative detection systems have been developed for the former organism and immunocytochemical techniques for the latter, allowing its visualisation in wood. Specificity studies on the antisera produced indicate that cross reactivity is limited to basidiomycetes, and in particular specific brown and white rot organisms. Cross reactivity can be diminished by suitable absorption. Western blot studies on L. lepideus indicate that the organism contains a number of antigenic species. Immunological methods are appropriate to research in the biodeterioration of wood and will prove valuable in the detection and identification of decay microorganisms.

During this investigation into the relationship between the domestic dry rot fungus, Serpula lacrymans, and some non-woody building materials, it was found that S. lacrymans removed calcium, silicon and iron from sandstone, and calcium, sulphur and iron from traditional plaster. The sequestered elements were located on its hyphae, especially in the form of calcium oxalate. Degradation of the sandstone was implicit, but not obvious microscopically. In addition, S. lacrymans selectively transported iron from these building materials through its mycelial system. These findings lend further support to the theory that this wood-decaying fungus has an special dependence upon masonry in buildings.

A questionnaire survey of building practitioners in Scotland was carried out with the aim of determining their experiences and views on the causes and treatment of dry rot. The practitioners' perceptions of the importance of key factors associated with the initiation, development and survival of the dry rot fungus Serpula lacrymans were determined and compared to scientific understandings of the organism and its effects in the built environment. Several potential misunderstandings amongst the practitioners were identified, particularly in their lack of understanding of the importance of proper building maintenance, as well as the perceived high importance of softwoods and relative non-importance of hardwoods and the low rating of the pH environment in dry rot attacks. The benefits, and drawbacks, of various dry rot treatment methods were also determined, with profiles of five treatment methods, which were rated in four specific categories, being produced. Analysis of these profiles revealed a potential interest in environmental control methods amongst the practitioners, though conventional techniques based on the removal of timber and chemical treatment remain the most widely used. Finally, a treatment strategy guide was developed from the responses, which highlighted the order of the 18 main features that the practitioners would consider in a dry rot treatment project. Of greatest concern was the apparent view that practitioners did not consider posttreatment building monitoring as being particularly important.

A stochastic cellular automaton for modelling the dynamics of a two-species fungal microcosm is presented. The state of each cell in the automaton depends on the state of a predefined neighbourhood via a set of conditional probabilities derived from experiments conducted on pairwise combinations of species. The model is tested by detailed comparison with larger-scale experimental microcosms. By employing different hypotheses which relate the pairwise data to the conditional probabilities in the model, the nature of the local and non-local interactions in the community is explored. The hypothesis that the large-scale dynamics are a consequence of independent interactions between species in a local neighbourhood can be excluded at the 5% significance level. The form of the interdependencies is determined and it is shown that the outcome of the interactions at the local neighbourhood-scale depends on the community-scale patterning of individuals. The dynamics of the microcosm are therefore an emergent property of the system of interacting mycelia that cannot be deduced from a study of the components in isolation.

The community dynamics of two- and three-fungal species interactions derived for a tessellated agar model system are described. The microcosm allows for the varied prescription of: (1) the number of fungal species interacting; (2) the spatial configuration (patchiness) of the distribution of individuals; (3) the magnitude of scale of spatial occupation by different fungal individuals; and (4) the operation of antagonistic mechanisms based on contact or longer range diffusible components. Stepwise logistic regressions for two-species interactions are used to inform the design of the multi-species interaction tessellations. The model prescribes and investigates complex parameters, such as spatiotemporal heterogeneity and microcosm scale (e.g. population patchiness and crossing times). Data are quantified as proportion, interface class and state transition class of viable fungal species. Spatiotemporal heterogeneity is represented using a novel application of principal component analysis which shows good intuitive agreement with visual assessment of the interaction outcome patterns, and allows effective comparison of the data as a whole. The model demonstrates the influence of the complex and coordinated behaviour of fungal mycelia on community development: interaction outcome of three-species interactions cannot be directly extrapolated from the relevant binary component interactions; interaction outcomes of the multi-species tessellations appears to be neither random nor fully deterministic; a degree of stochasticity is apparent in all tessellation arrangements; the smaller scale tessellations produce more consistent interaction outcome results, probably because experimental scale affects the duration of transient behaviour; and different initial spatial configurations of inoculum (irrespective of inoculum quantity or proportion) influence community development and reproducibility.

We report the first successful culturing and confirmation of identity (via sodium dodecyl sulphate polyacrylamide gel electrophoresis, SDS–PAGE) of Serpula lacrymans (the dry rot fungus) derived from basidiomes and mycelia growing in the ‘wild’. The fungus was found growing on well decayed coniferous wood within the Narkanda region of the Western Himalayas at between 2800 and 3100 m above sea level (a.s.l.). The ‘wild’ habitat of the fungus is described, as is the isolation of Serpula himantioides also found in these regions. Temperature, osmotic potential, initial pH and air-current influenced the average colony extension rate of ‘wild’ and a selection of building isolates on 2% malt extract agar. The ‘wild’ and building isolates behaved as two separate cohorts; the ‘wild’ isolates appeared to be less affected by extremes of temperature, whereas building isolates extended more rapidly at the moderate microenvironmental regimes.

The dry-rot fungus Serpula lacrymans has a maximum growth temperature of 28°C which is an unusual feature in comparison to other Serpula species. This has led to the investigation of S. lacrymans sensitivity to higher temperature regimes with respect to increased thermotolerance and the production of heat-shock proteins (hsps). The strategy employed in this study has been to correlate protein synthesis with thermotolerance and the heat-shock response. Protein profiles generated by one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (1D SDS-PAGE) of fungal colonies exposed to optimal, supraoptimal (sublethal) and lethal temperatures were probed with rabbit anti-GRoEL serum for the presence of the 60-kDa heat-shock protein. The preliminary findings indicate that an important heat-shock protein, a GRoEL analogue, is produced by S. lacrymans and that this basidiomycete undergoes the classic heat-shock response.

The growth rates, decay capacity and acid production of Serpula lacrymans (Schumacher ex Fr.) Gray and Coniophora puteana (Schumacher ex Fr.) Karst. were monitored under experimental conditions by cultivating these organisms on a range of media supplemented with varying concentrations of calcium and other divalent metal ions. Both C.puteana and S.lacrymans had maximal growth rates when cultivated on malt extract agar and wood blocks incubated on this medium gave substantial decay rates. By contrast, C.puteana cultivated on minimal medium supplemented with 21 mM calcium gave reduced growth rates whilst intermediate concentrations of calcium had little effect on the growth of the organism. In all cases, C.puteana cultivated on calcium containing minimal media gave minimal decay of the wood blocks. Finally C.puteana acidified all media and no indication of buffering was observed. Results obtained from S.lacrymans demonstrated that increasing calcium nitrate concentration promoted decay of wood blocks and increased organism growth rates. S.lacrymans also acidifed the various media used, but surface pH profiles indicated that the organism was able to buffer acid production to a certain extent when calcium nitrate, or other divalent ions, were available.

The optimum (22 and 25 °C respectively), supraoptimal (sublethal) and the minimum lethal temperature regimes for Serpula lacrymans and S. himantioides were established. Exposure of S. lacrymans and S. himantioides to supraoptimal temperature regimes induced a transient tolerance to subsequent, normally lethal heat treatments (40° for 2 and 3 h respectively). An optimum thermotolerance training ‘window’ of 28° for 24 h and 25° for 48 h was appropriate for S. lacrymans , whereas thermotolerance training improved at 28 and 30° with increasing period (1–72 h) in the case of S. himantioides . The reported thermosensitivity of S. lacrymans compared to S. himantioides appears to be reflected in the contrasting thermotolerance-training profiles presented here, and may contribute to the general absence of S. lacrymans from the wild in temperate Europe.

There have been a number of advances in the understanding of the physiology of the dry rot fungus, Serpula lacrymans, in the last decade. Specifically, studies on the natural origins of the fungus, morphogenesis, toxicant tolerance, environmental sensitivity, nitrogen metabolism, utilization of non-woody materials and biological control have all contributed to this understanding and each is discussed in relation to potential control strategies for the future. In addition, molecular studies involving detection, monitoring of speciation and the heat shock response of Serpula lacrymans have provided new insights into an organism which is uniquely destructive in the built environment.

A range of isolates of Serpula lacrymans show identical molecular profiles by Western Blotting or lectin staining. One isolate, BF-050, showed differences in silver stained protein profiles from old mycelium but profiles from young mycelium of BF-050 were identical to the type strain of S. lacrymans FPRL 12C. Both S. lacrymans and the related organism, Serpula himantoides, shared different profiles for old and young mycelium confirming that growth phase antigens/proteins are not limited to S. lacrymans. Lectin staining profiles could distinguish between S. lacrymans FPRL 12C, BF-015B, S. himantoides and all other basidiomycete organisms tested. Differences between strains of S. lacrymans including BF-050, were not apparent.

Using a standard medium (malt extract agar) and a minimal essential medium designed to mimic the carbon: nitrogen ratio in wood, a number of Trichoderma isolates were screened for their ability to kill Serpula lacrymans . From the results one Trichoderma species, T. harzianum 25, proved to be the most efficient at killing S. lacrymans . In addition, modifications to the nitrogen and iron concentrations of the minimal medium provided indications that the level of these two elements could prove important in the biological control of the dry rot fungus in wood.

Consequences of initial spatial organisation of model fungal communities upon their spatio-temporal development were investigated. Dynamics of prescribed two- and three-species 'communities' developing on tessellated agar tile model systems were analysed in terms of literal maps, principal component analyses, or as the proportion of species extant within tiles. It was established that for two-species interactions of equal patch size, large-scale (i.e. many constituent tiles) behaviour could be extrapolated from the relevant small-scale (i.e. pairs of tiles) interactions. However, relative patch sizes (scale) of species within tessellations influenced the times taken by individuals to colonise tiles and, hence, temporal behaviour of the system. Outcome of arrangements involving three species of equal patch size and inoculum potential, and prescribed with different mixing patterns, could not be directly extrapolated by reference to the outcome of pair-wise interactions between constituent species. Three-species arrangements attempt to limit assembly of lateral aggregates of individuals (patch size) and hence any effects of tile colonisation times, so as to reveal effects of nearest neighbour context within the complex community. Such arrangements indicate that spatial configuration of inoculum influences community development and reproducibility. They also suggest that spatial distribution of species affects persistence of individuals, which would otherwise be expected to be eliminated from the system. Two-species interactions appeared generally more reproducible than those comprising three species, and the sensitivity of fungal community development to temperature was not solely associated with influence on colony extension rate.

Antigenic proteins from isolates of Serpula lacrymans isolated from locations around the world and from other wood decaying basidiomycetes were compared after Western blotting using an antiserum produced against S. lacrymans strain FPRL 12C. All isolates of S. lacrymans gave identical antigen profiles. A further isolate, originally identified as S. lacrymans , gave a slightly different profile but was almost certainly an isolate of the closely related organism Serpula himantioides . All other organisms gave very different antigenic profiles indicating that identification of species would be possible using immunoblotting. The major antigens of S. lacrymans , grown in liquid culture, were represented in the immunoblots as broad, somewhat indistinct, bands and the antigenic profiles of many of the other basidiomycetes also showed this characteristic. In contrast the major antigens extracted from both S. lacrymans infected wood and actively growing regions of mycelial cultures of the organism were represented by discrete bands. However the overall antigenic profiles of each of these extracts were similar to that of the organism cultured in liquid medium in terms of the actual antigenic species present.

Interrelations of fungal mycelium with other soil biota are of paramount importance in forestry and soil ecology. Here we present the results of statistical analysis of a comprehensive data set collected in the first (and the only) British fungus sanctuary over a period of four months. The variables studied included a number of soil properties, bacteria, protozoan flagellates, ciliates and amoebae, microbial and plant feeding nematodes, various microarthropods, and two fungal biomarkers--glomalin and ergosterol. One way ANOVA showed that the dynamics of the microbiota studied was influenced by seasonal changes. Superimposed on these changes, however, was variability due to biological interactions and habitat characteristics. Two fungal biomarkers, ergosterol and glomalin, were differently influenced by other biota and abiotic variables. The results indicate that the dynamics of soil fungi is influenced not only by soil microarthropods, but also by those found in forest litter. The overall outcome, therefore, is likely to be very complex and will depend upon specific conditions of any particular ecosystem.

Molecular and morphological parameters of Serpula lacrymans isolates from various sites in the built environment in Europe and Australia were compared to similar parameters of ‘wild’ isolates from India, the Sumava Mountains (Czech Republic) and Mount Shasta (USA). The Indian, Czech Republic and all of the building isolates bar one showed identity in both molecular and morphological features. The Australian and the USA isolates (BF-050 and USA’94 respectively) showed specific morphological differences and could be separated on the basis of randomly amplified polymorphic deoxyribonucleic acid polymerase chain reaction (RAPD PCR) with the USA isolate being least closely related to the S. lacrymans type strain of FPRL12C. ITS sequence data revealed two base differences between FPRL12C and BF-050 in the 673 sequenced, nine differences between FPRL12C and USA’94 and 16 differences between USA’94 and the closely related organism Serpula himantioides. The possible evolutionary relationships between the various isolates are discussed along with suggestions for the origin of S. lacrymans as a scourge of the built environment in many temperate areas of the world. > 2003 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

A microcosm system is described which permits assessment of the progressive growth of filamentous fungi through soil. We report on its application to measure the effects of Coriolus versicolor and Phanerochaete chrysosporium upon the sorptivity and water repellence of a mineral soil, measured using a miniature infiltration device. Both fungal species caused moderate sub-critical repellence. Since the pore structure was unaffected, the repellence was probably due to hydrophobic substances of fungal origin. This is the first report of changes in soil repellence caused by the growth of potential xenobiotic bioremediating fungi. The potential consequences are discussed.

Timber represents a rich source of potential nutrients for a wide variety of macro-organisms (e.g. insects and marine borers) and micro-organisms (notably fungi and bacteria). Timber is susceptible to these agents during both production and in-service use, though degradation by them is not always inevitable and is usually associated with misuse or inappropriate use. However when timber is to be used in some types of environment, notably where relatively high levels of moisture are available, protective systems are necessary to prevent decay. Currently such systems often rely on the use of chemical treatments but alternative strategies are under development at a number of centres and these come under the headings of environmental control, biological control and the use of natural products as wood preservatives. This chapter will explore each of these systems in the context of the control of the dry rot fungus Serpula lacrymans,a wood decay basidiomycete which causes severe damage to wooden elements of buildings in temperate areas and whose natural home appears to be the Himalayan foothills. Discussion of these natural processes and products will be preceded by a description of the current wood preservation scenario and of the pressures which are bringing about change in the associated industry.

Wood as material biotechnology in the study of brown and white rot decay biopulping enzymes in pulp bleaching anaerobic treatment of pulp mill effluents bioremediation of soils contaminated with organic wood preservatives bioremediation of wood treated with preservatives by using white rot fungi biotechnology production of wood composites special (secondary) metabolites from wood wood/bark extracts as adhesive and preservatives ethanol production and forest products' wastes production of mushrooms from wood waste substrates drugs from plants the role of biological metal chelators in wood degradation and xenobiotic degradation biological control of wood decay biological control of forests pests - a biological perspective transgenic trees the use of molecular methods for the detecting and identification of wood decay fungi.

Summary The Wood Research Group at Dundee Institute of Technology is currently investigating a number of parameters associated with methodology for) the preservation of timber and the detection of decay organisms within timber. Application of specific methodologies allowing the in situ treatment of timbers with preservative agents and the relatively non-destructive testing of timbers for decay organisms are particularly appropriate to conservation strategies for wooden structures. Currently used procedures for remedial treatment of such structures require visual identification of decayed wood followed by removal and replacement of defective timbers. An alternative strategy is required where artefacts of historical or archaeological importance are under threat. The development of immunological methods for the detection of incipient decay (i.e. the presence of decay organisms before they have caused damage to timber) and the use of water soluble diffusible biocides such as boron based salts will be discussed in this presentation. Applications of these methods to two historical artefacts present in Dundee, viz. the UNICORN, the oldest surviving European built warship still afloat, and the DISCOVERY, a research ship used in Antarctic exploration in the early part of this century, will also be discussed.

The extraction and purification of glial fibrillary acidic protein (GFAP) from human fibrillary cerebellar astrocytoma is described. Using an immunoperoxidase method, antisera raised to the protein showed specific staining of astrocytes in normal spinal cord and in tumours of astrocytic origin. A double antibody radioimmunoassay for GFAP in tissue extract was developed, the detection limit of the assay being 360 pg. Extracts of tissues other than brain or spinal cord did not cross-react significantly in the assay, neither did purified preparations of myelin basic and S-100 proteins. Levels of GFAP in normal CNS tissue were highest in spinal cord (1370 μg/g wet weight) but a level of 3050 μg/g wet weight was detected in a fibrillary astrocytoma.

A herpes simplex virus type 1 (HSV-1) mutant, ts1204, which has a temperature-sensitive (ts) mutation located within genome map coordinates 0.318 to 0.324, close to but outside the coding sequences of the glycoprotein gB gene, has been characterised. Although this mutant adsorbed to the cell surface at the nonpermissive temperature (NPT), it failed to penetrate the cell membrane. As a consequence of this defect, high multiplicities of infection of ts1204 blocked subsequent infection of cells by wild-type HSV-1. By contrast, at the NPT, superinfection of cells with HSV-2 was not inhibited by prior infection with ts1204. The penetration defect could be overcome either by brief incubation of mutant virus-infected cells at the permissive temperature, or by treatment of the cells with polyethylene glycol, a compound which promotes fusion of membranes. Upon continued incubation of ts1204-infected cells at the NPT, low numbers of capsids were assembled. Although these capsids all had some internal structure, they did not contain DNA. Another mutant, ts1208, which lies in the same complementation group as ts1204, penetrated cells normally at the NPT, but like ts1204, had a defect in the formation of functional capsids. Evidence presented in this paper suggests that the gene in which the ts1204 and ts1208 lesions map encodes a structural polypeptide.

We have characterized a temperature-sensitive mutant of herpes simplex virus type 1 (HSV-1), 17tsVP1207, that induces a thermolabile ribonucleotide reductase activity. This mutant was derived from the multiple mutant tsG. Fine-structure mapping studies showed that the defect in 17tsVP1207 lies within an 800 bp sequence between genome map coordinates 0.580 and 0.585 in the gene encoding a polypeptide of 140 000 mol. wt. (Vmw136, ICP6). Since the mutation in this polypeptide produced a temperature-sensitive ribonucleotide reductase activity, Vmw136 must be a component of the herpes simplex virus-induced ribonucleotide reductase. The mRNA of Vmw136 has a common 3' terminus with an mRNA encoding a 38 000 mol. wt. polypeptide (Vmw38). Although the polypeptide-coding sequences of these mRNAs do not overlap, monoclonal antibodies against Vmw136 immunoprecipitated Vmw38 as well as Vmw136 from wild-type HSV-1-infected cells. Our data do not exclude the possibility that Vmw38 is part of the ribonucleotide reductase complex but suggest that this species on its own is not responsible for the HSV-induced enzyme activity.

Summary Antisera to two herpes simplex virus-type 1 (HSV-1) immediate-early gene products (IE12 and IE175) have been produced using oligopeptides, constructed on the basis of proposed DNA coding sequences, as immunogens. In both cases the synthetic peptides were linked to bovine serum albumin via an N-terminal tyrosine prior to immunization. Both the IE12 and the IE175 antisera reacted with their respective HSV-1 antigens and with antigens produced by the HSV-1 immediate-early mutant tsK but not with functionally equivalent antigens induced by HSV-2. IE12 induced by tsK was found to have an altered mobility with respect to the wild-type IE12 and its precipitation was accompanied by a second, minor, component of lower mobility. Revertants of tsK gave similar results. Labelling IE12 with a variety of amino acids indicated that the first of three possible initiation codons was used in its translation from mRNA. The results imply that the other initiation codons were not used. Wild-type IE12 is produced for at least 3 h after release of cycloheximide block and appears to be turned over rapidly.

The production of antisera to specific proteins using as immunogens short, synthetic oligopeptides corresponding in sequence to regions of the proteins is analysed. Of 103 oligopeptides used for this purpose and reported in the literature before the end of 1983 all those corresponding to N or C terminal sequences produced antisera reacting with the complete protein. Of 69 oligopeptides corresponding to internal sequences only 71% were successfully used to prepare antisera. An analysis of these 69 oligopeptides showed that peptides of less than 10 amino acids were unlikely to produce useful antisera and that the more hydrophilic peptides were marginally more useful than those less hydrophilic.

Serum levels of myelin basic protein (M.B.P.), a nervous-system-specific protein, were measured in 157 patients after head injury and related both to the type of brain damage and to the clinical outcome assessed three months after injury. Mean concentrations of M.B.P. in patients with severe intracerebral damage, with or without associated extracerebral haematoma, were significantly raised at the time of admission and remained high for two weeks after injury. In patients with extracerebral haematoma not associated with severe intracerebral damage mean M.B.P. values rose four to six days after injury and were significantly raised only in patients with poor eventual outcome. Mean serum-M.B.P. concentrations in patients with a good outcome after injury were similar to those in controls. In patients with a poor outcome the mean M.B.P. levels between two and six days after injury were significantly higher than in those with a good outcome. The assay of serum-M.B.P. may be valuable in assessment of severity of brain damage in patients after head injury and in prediction of outcome.

Herpes simplex virus (HSV) immediate early (IE) transcription is known to be stimulated by a structural component of the virion which interacts, either directly or indirectly, with specific regulatory sequences located far upstream from IE messenger RNA 5'-termini. The aim of the work described in this paper is the mapping and identification of the virion component. Cloned HSV DNA fragments derived from various parts of the genome were cotransfected into BHK cells together with chimaeric plasmids which contained the thymidine kinase gene under IE control. Stimulation of thymidine kinase synthesis was elicited by cloned EcoRIi (0.63 to 0.72 map units), BamHIf (0.64 to 0.69) or EcoRIb (0.72 to 0.87). Cloned BamHIf had the same specificity as the virion component, since it stimulated thymidine kinase expression only from chimaeric plasmids which contained functional IE-specific regulatory sequences. The effect of EcoRIb was not confined to plasmids with IE-specific regulatory regions, suggesting a more general stimulatory role for one or more of the polypeptides encoded by this fragment. A subclone containing a 2.7 X 10(3) base-pair fragment of BamHIf (pMC1) was active in the cotransfection assay, and the effect was abolished by an eight base-pair insertion into the middle of this fragment. The only polypeptide known to map entirely within the HSV genome region defined by pMC1 was identified as the major tegument species Vmw65. The results therefore suggest that Vmw65 is the virion component which trans-activates HSV IE transcription.

Scanning laser densitometry was performed on immuno- and dot blots developed on nitrocellulose by treatment of the nitrocellulose with xylene. This method permits the development of simple methods for recording results of immunoblots and of producing semi-quantitative assays from dot blots.

The kinetics of the corticosteroidogenic response to adrenocorticotrophin (ACTH) have been investigated using collagenase dispersed adrenocortical cells. Following the addition of ACTH at a concentration that was maximal for steroidogenesis, there was a time-lag of about 3 min before increased steroidogenesis became apparent. This lag was extended (about two-fold) in the presence of a half-maximal concentration of ACTH. Preincubation of cells with submaximal concentrations of both cycloheximide and puromycin extended the time-lag observed following ACTH addition. Increasing doses of cycloheximide or puromycin concomitantly inhibited protein synthesis and steroidogenesis. Moreover cycloheximide, at a dose that halved protein synthesis, also inhibited steroidogenesis by 54–61% for a range of ACTH concentrations (1 × 10 −4 to 1 × 10 −2 I.U./ml). It is concluded that the delay before ACTH-stimulated steroidogenesis is not attributable solely to the time taken for ribosomes to read of from the mRNA strand, the code for protein regulator(s). The results are discussed in terms of steroidogenic mechanisms whereby ACTH either induces de novo protein synthesis or activates a pre-existing, but labile, protein. In this latter scheme the steroidogenic rate observed under various conditions would be directly dependent upon the intracellular level of such an activated protein regulator. The half-life of labile protein, implicated as regulating steroidogenesis, was estimated at 2–4 min in this adrenal cell suspension system.

The effects of cholera toxin on adrenal weight in hypophysectomized rats were investigated, in an attempt to demonstrate an ACTH-like, adrenal trophic effect of the toxin. The results suggested that the toxin probably exerts its ACTH-like action on the adrenal via adenylate cyclase. Cholera toxin was also shown to have a thermolytic action, similar to that of ACTH, probably due to stimulation of adrenal glucocorticoid secretion.

The development of a double antibody radioimmunoassay for myelin basic protein in tissue extract, cerebrospinal fluid and unextracted serum is described. Detection limits for the assays were: for tissue extract 3.1 ng, for cerebrospinal fluid 30 ng/ml and for serum 13.6 ng/ml. Specificity for myelin basic protein is suggested by lack of cross reactivity by tissues other than brain and presence of immunoactivity in cerebrospinal fluid and serum only in samples from patients with brain damage due to intracranial surgery or head injury. Immunoactivity in brain extracts and serum from patients with severe brain damage was indistinguishable from authentic myelin basic protein on serial dilution. Cross reacting material in cerebrospinal fluid samples differed from the authentic protein on serial dilution and on Sephadex G-100 chromatography, and may represent breakdown products of myelin basic protein. Mean serum concentrations of myelin basic protein in patients one day after head injury were significantly higher than in control patients with or without other neurological disease. Highest serum myelin basic protein concentrations were found in patients with severe primary intracerebral damage, with peak levels occurring 2–3 days after head injury. In patients with extracerebral haematoma, without intracerebral damage, the peak serum myelin basic protein concentrations occurred 7–10 days after injury. It is suggested that the measurement of serum myelin basic protein concentrations may be valuable in the management of patients after head injury.

Myelin basic protein-like immunoactivity was measured in the serum of patients after cerebrovascular accident (CVA) using a double antibody radioimmunoassay for myelin basic protein with a detection limit of 3 ng/ml serum. For up to 6 days after ictus, serum myelin basic protein levels in patients with severe CVA and patients who died as a result of CVA were significantly greater than those in control patients, patients with moderate CVA and patients surviving CVA. All patients with serum myelin basic protein levels greater than the range found in control subjects subsequently died. Serial dilutions of positive sera suggested that the immunoactivity differs from authentic myelin basic protein and may represent breakdown products of the protein. Serum from some patients with a previous history of moderate CVA had myelin basic protein binding activity consistent with the presence of antibodies to the protein.