Fungal biosorption of silver particles on 20th-century photographic documents

Microbial deterioration is a common problem in photographic collections and is considered a major cause of loss of documents. However, few studies so far have been addressed to biological damage on these materials. Several species of naturally occurring fungi can cause infections on the gelatin-silver emulsion of both positive and negative photographic material, producing defacement and loss of mechanical and aesthetical properties of the objects. In this study a particular phenomenon, spontaneously caused by fungi on 20th-century photographic films and positive supports, was documented by means of variable pressure scanning electron microscopy (VP-SEM) combined with electronic dispersion spectroscopy (EDS). This technique allowed the observation of entire, unaltered films without metallisation thus with a not invasive approach. The ability of some fungi to alter the distribution of silver crystals in the gelatin emulsion was described thanks to a backscattered electrons detector that showed differences in the atomic number of the visualised objects, giving rise to an appreciable contrast in case of different chemical composition.     

UV-reflecting and absorbing body regions in gentoo and king penguin: Can they really be used by the penguins as signals for conspecific recognition?

Photographs of gentoo and king penguins were taken in the field on a bright and sunny day first in colour (here reproduced in black and white) and then, seconds later, through a filter that transmits only UV radiation and blocks all visible light. Because of the lower light intensity and different focal point of UV, it is unavoidable that the UV photographs turn out less sharp and less well focused than photographs taken with visible light. Comparisons of the two sets of photographs show that king penguins with white (but not yellow or orange) auricular patches reflect UV from these areas. Furthermore, the beaks of juvenile gentoo penguins, but not those of the adults, are UV reflectant. The findings are discussed in view of recent suggestions that UV reflection in penguins could be part of a communication system. However, this paper argues that as long as UV perception in penguins has not been demonstrated, UV reflection in penguins ought to be seen as an “associative phenomenon” with no significance to penguin behaviour.     

The revenge of time: fungal deterioration of cultural heritage with particular reference to books, paper and parchment

Hyphomycetous fungi - so called 'mould'- are the most important agents of biodeterioration in museums, museums' storage rooms, in libraries, collections and restoration studios. Fungi are able to live at low water activities, they are perfectly adapted to indoor environments and thrive in microclimatic niches caused by condensation, lack of ventilation or water retention by hygroscopic materials. Fungi spoil valuable pieces of art aesthetically, mechanically, chemically and by degradation of organic components. Historical material made of paper and oil paintings with high amounts of organic binders are especially susceptible to fungal deterioration. In order to prevent fungal contamination or to treat already contaminated objects an integrated approach including climate control, material-specific cleaning and application of carefully selected biocides is necessary.     

Color pattern formation on the wing of a butterfly Pieris rapae. 2. Color determination and scale development

It has been shown that microcautery on the prospective apical black region of the early pupal forewing of a butterfly, Pieris rapae , causes alteration of the scale color on the adult wing and a delay in histogenesis of the pupal wing. From these results, it has been assumed that the developmental delay of scale cells in the pupal wing alters their developmental fate and the hypothesis that different color fates of scales are determined by differences in the developmental timetables between scale cells is proposed. In this study, we attempted to find the developmental timetables of individual scales expressing specific color to test this hypothesis. It was found that the holes on the upper surface of a scale become larger as they develop and the hole sizes of scales in the white region are always larger than in the black region on the same wings either during pupal period or after eclosion. This suggests that the scale hole size is a good index that reflects developmental rate of the scale and a difference in the hole size between adult scales is attributed to a difference in the developmental timetables when their ancestral scale precursor cells were in the pupal period. A comparison of the hole sizes between adult scales in different color regions suggested that normal white scales were in a more advanced state than were the black ones but white scales induced by microcautery were in a less advanced state than black ones on the same wing. This supports our hypothesis.     

Book Reviews

Book reviewed in this article:
The Cattleyas and their Relatives. Vol. III. Schomburgkia, Sophronitis, and other South American Genera. Carl L. Withner. 136 pp., 85 colour photographs, numerous b/w line drawings.
'Chinese Wilson'. A Life of Ernest H. Wilson 1876–1930. Roy W. Briggs with a foreword by Roy Lancaster.
Gardens of Historic Charleston. James R. Cothran. 177 pp., numerous colour and b/w photographs, illustrations and portraits.
Science in the Pleasure Ground. A History of the Arnold Arboretum. Ida Hay. 349 pp., 20 colour photographs, numerous black and white photographs, maps and plans.     

BOOK REVIEWS

Book reviewed in this article:
Private Gardens of England. Penelope Hobhouse. 223 pp., 65 colour plates, 160 black and white photographs.
Flower Painting. Clare Sydney. 80 pp., 32 colour and 9 black and white Manual of Cultivated Broad-leaved Trees and Shrubs Vo13 Pru-Z. Gerd Krussmann illustrations.
The Brightest Jewel. A History of the National Botanic Gardens, Glasnevin, Dublin. E. Charles Nelson and Eileen M. McCracken
Porophyllum Saxifrages. R. Horn+, K.M. Webr and J. Byam-Grounds
Cacti for the Connoisseur. John Pilbeam     

A non-fluidic, fluorometric assay for the detection of fungi on cultural heritage materials

Cultural heritage materials are particularly susceptible to biodeterioration by fungi. Improper care and storage of artifacts contaminated with fungal material can promote the growth of these microscopic organisms and the inevitable deterioration that follows. Technology capable of detecting vegetative fungi and their reproductive structures could facilitate the struggle against fungal biodeterioration. Archivists and conservators could be notified of fungal contamination within a collection and apply pre-emptive measures, such as modification of environmental conditions, to prevent biodeterioration. The aim of this study was to improve and simplify a fluorometric assay used for the early detection of minute quantities of fungal biomass on cultural heritage materials. To this end we have successfully developed a non-fluidic assay in which fluid transfers, centrifugation steps, and much of the specialized equipment formerly needed to perform the assay are eliminated. The time required for completion of the assay was reduced to 30 min. Use of the assay was also expanded to include the early detection of viable fungal conidia from several species of fungi. These refinements will expedite implementation of this technology by archivists and conservators as they monitor and combat the fungal deterioration of cultural heritage materials.     

BOOK REVIEWS

Book reviewed in this article:
Wild Orchids of Scotland. Brian Allan and Patrick Woods. 135 pp., many colour photographs, line drawings and maps. HMSO, Edinburgh. 1993.
The Orchids of Peninsular Malaysia and Singapore. Gunnar Seidenfaden and Jeffrey Wood. 779 pp., 315 black & white line drawings, 48 colour plates and 1 black and white photograph. Olsen & Olsen, Fredenborg, Denmark. 1992.
The Orchid Book- a Guide to the Identification of Cultivated Orchid Species. Ed. J. Cullen. 529 pp., 16 colour photographs, numerous line drawings. Cambridge University Press. 1992.
Iris of China. James W. Waddick and Zhao Yu-tang. 192 pp., 31 colour photographs, 21 plates of line-drawings. Timber Press, Oregon. 1992.
Garden Pests & Predators — the wildlife in your garden and its ecological control. Elfrida Savigear. 128 pp., line-drawings. Blandford, London. 1992.
Seeds of Woody Plants in North America. James A. Young and Cheryl G. Young. 407 pp. Dioscorides Press, Oregon. 1992.
Gardening with Camellias. A complete guide. Jim Rolfe. 176 pp., 175 colour photographs. Godwit Press Ltd., New Zealand (distrib. in UK by Batsford). 1992.
Success with Rhododendrons and Azaleas. H. Edward Reiley. 285 pp., 87 colour and 33 black-and-white photographs, maps. Timber Press, Oregon. 1992.
The Old Rose Advisor. Brent C. Dickerson. 400 pp., 274 colour plates. Timber Press, Oregon. 1992.
The Subtropical Garden. Jacqueline Walker. 175 pp., many colour photographs. Godwit Press Ltd., New Zealand (distrib. in UK by Batsford). 1992.     

SHORT REVIEWS AND NOTICES

A CONCISE GUIDE TO THE FLOWERS OF BRITAIN and Europe. Oleg Polunin. xix + 107 pp., 192 plates of colour photographs. Oxford University Press, Oxford and New York. 1987.
FLOWERS OF GREECE AND THE BALKANS, A field guide. Oleg Polunin. xv + 592 pp., 82 plates of colour photographs, several pages of line drawings. Oxford University Press, Oxford and New York. 1987.
the englishman's flora. Geoffrey Grigson. 478 pp., 44 black and white woodcuts. Phoenix House, London. 1987.
bee orchids. Stephen Blackmore. ISBN 0 85263 745 4.
buttercups. Stephen Blackmore. ISBN 0 85263 763 2.
willows of the British isles. Theresa Brendall. ISBN 0 85263 765 9.
All 24 pp., illustrated in colour and black and white. Shire Publications Ltd., Princes Risborough. 1985.     

Visual aspects of species recognition in the damselfish Dascyllus aruanus L. (Pisces,Pomacentridae)

Attraction was found to be a reliable indicator of species recognition in the damselfish Dascyllus aruanus. Isolated fish are attracted to live or dead conspecifics significantly more than to heterospecifics. Attraction persists towards black and white photographs. Using photographs it was shown that certain parts of the pattern are more important for recognition than others. Of the three black bars of the normal colour pattern, the central is the most important, and the anterior the least so. Two alternative criteria for demonstrating species recognition in a boldly coloured reef fish, aggression and attraction, are contrasted.     

Short Reviews

THE WEED FLORA OF EGYPT. Loutfy Boulos & M. Nabil el-Hadidi. Pp. 178, 163 line illustrations. The American University in Cairo Press
OF PLANTS AND PEOPLE. Charles B. Heiser Jr. Pp. 250, 68 black and white photographs. University of Oklahoma Press
FLORA OF THE CAYMAN ISLANDS. George R. Proctor. Pp. 834, 256 text figs. + 3 maps
DIAGNOSIS OF MINERAL DISORDERS IN PLANTS. J.B.D. Robinson, general editor; 2 volumes. 1 Principles, C. Bould, E.J. Hewitt and P. Needham, Pp. 176, illustrated in colour and black and white
PLANT FACTS AND FANCIES. Sylvia Woods, drawing by Yvonne Skargon. Pp. 93, with line illustrations. Faber & Faber 1985
JOHN NASH. Sir John Rothenstein. Pp. 128, with colour and black and white illustration and a few black and white photographs. Macdonald & Co. (London) 1983
FLORA OF KUWAIT, VOLUME 1: DICOTYLEDONEAE. Hazim S. Daoud
THE NAMES OF PLANTS. D. Gledhill. Pp. 159. Cambridge University Press
STUDIES ON THE TIHÃMAH - THE REPORT OF THE TIHÃMAH EXPEDITION 1982 AND RELATED PAPERS
SONORAN DESERT SPRING. John Alcock. Pp. 194, numerous photographs, mostly in black and white
FLORA OF CYPRUS, VOLUME TWO. R.D. Meikle. Pp. 1137 (Pp. 833–1970), 52 text figs. Bentham-Moxon Trust     

Short-term testing of antifouling surfaces: the importance of colour

Data from short-term biofouling assays are frequently used to evaluate the performance of antifouling (AF) coatings. There are a large number of factors, however, that may influence community development. One such factor is colour. The hypothesis was that differences in colour may impact the short-term development of a biofouling community and therefore bias the results. An experiment was designed to investigate the effect of black and white substrata on settlement of fouling organisms in the field. Both Ulva sp. and Spirorbis sp. had significantly higher settlement on black surfaces. This result emphasises the importance of considering colour and other factors when undertaking short-term testing of AF coatings.     

Physical and chemical properties of primary defences in Tenebrio molitor

Prevention and reaction are the foundation for any defence system. In insects, the primary defences against pathogens and parasites limit invasion; the secondary ones (e.g. immune system) act when the cuticle and other primary defences fail. Because investment in both aspects of defence may be costly, they should be regulated in a plastic or variable way in accordance with the risk of infection. The mealworm beetle Tenebrio molitor L. changes cuticle colour and its resistance to fungal infection when subject to high population density, although such resistance is a result of the primary (cuticle) defences rather than the secondary (immunological) ones. The present study tests the hypothesis that the physical and chemical properties of the primary defences in T. molitor change with cuticular darkness. Beetles expressing black phenotypes (or with darker cuticle) have a thicker cuticle, with four well organized layers (epi‐, exo‐, endocuticle and formation zone) and more melanin than tan beetles. The cuticle properties investigated in the present study are likely to be the underlying mechanisms of pathogen resistance in black beetles, including the content of carbonylated proteins, which in black beetles was almost half that of tan beetles after exposure to ultraviolet radiation. It is proposed that, in polyphenic insects (such as mealworm beetles), primary and secondary defences are regulated pleiotropically, with the genes responsible for the expression of one defence having a positive effect on others, whereas, in polymorphic insects, there is no such link and so investment in one defence may impair others.     

Differential foraging success across a light level spectrum explains the maintenance and spatial structure of colour morphs in a polymorphic bird

Detectability of different colour morphs under varying light conditions has been proposed as an important driver in the maintenance of colour polymorphism via disruptive selection. To date, no studies have tested whether different morphs have selective advantages under differing light conditions. We tested this hypothesis in the black sparrowhawk, a polymorphic raptor exhibiting a discrete white and dark morph, and found that prey provisioning rates differ between the morphs depending on light condition. Dark morphs delivered more prey in lower light conditions, while white morphs provided more prey in brighter conditions. We found support for the role of breeding season light level in explaining the clinal pattern of variation in morph ratio across the species range throughout South Africa. Our results provide the first empirical evidence supporting the hypothesis that polymorphism in a species, and the spatial structuring of morphs across its distribution, may be driven by differential selective advantage via improved crypsis, under varying light conditions.     

Fruit Colour Preferences of Redwings (Turdus iliacus): Experiments with Hand-Raised Juveniles and Wild-Caught Adults

Certain fruit colours and their contrast with the background coloration are suggested to attract frugivorous birds. To test the attractiveness of different colours, we performed three experiments in laboratory with controlled light conditions. In the first two experiments, we studied the fruit colour preferences of naive juvenile redwings. In the third experiment, we continued to investigate whether the contrast of the fruit colour with the background coloration affects the preference of both naive juveniles and experienced adult redwings. In the first experiment, juvenile birds preferred black, UV‐blue and red berries, to white ones. In pairwise trials, a new set of juveniles still preferred red berries to white ones. When testing the effect of contrasts on their choice, juveniles preferred UV‐blue berries to red ones on a UV‐blue background. However, no preference was found, when the background was either red or green. Adult redwings preferred UV‐blue berries to red ones on all backgrounds. According to these results, juveniles seem to have an innate avoidance of white berries. Furthermore, the foraging decisions of fruit‐eating birds are affected more by fruit colour than its contrast with background coloration, at least when contrasting displays are encountered from relatively short distances. Differences in preferences of adult and juvenile birds also indicate that learning seems to play a role in fruit choices.     

The effect of surface colour on the formation of marine micro and macrofouling communities

The effect of substratum colour on the formation of micro- and macro fouling communities was investigated. Acrylic tiles, painted either black or white were covered with transparent sheets in order to ensure similar surface properties. All substrata were exposed to biofouling at 1?m depth for 40?d in the Marina Bandar al Rowdha (Muscat, Sea of Oman). Studies were conducted in 2010 over a time course of 5, 10 and 20?d, and in 2012 samples were collected at 7, 14 and 21?d. The densities of bacteria on the black and white substrata were similar with the exception of day 10, when the black substrata had a higher abundance than white ones. Pyrosequencing via 454 of 16S rRNA genes of bacteria from white and black substrata revealed that Alphaproteobacteria and Firmicutes were the dominant groups. SIMPER analysis demonstrated that bacterial phylotypes (uncultured Gammaproteobacteria, Actibacter, Gaetbulicola, Thalassobius and Silicibacter) and the diatoms (Navicula directa, Navicula sp. and Nitzschia sp.) contributed to the dissimilarities between communities developed on white and black substrata. At day 20, the highest amount of chlorophyll a was recorded in biofilms developed on black substrata. SIMPER analysis showed that Folliculina sp., Ulva sp. and Balanus amphitrite were the major macro fouling species that contributed to the dissimilarities between the communities formed on white and black substrata. Higher densities of these species were observed on black tiles. The results emphasise the effect of substratum colour on the formation of micro and macro fouling communities; substratum colour should to be taken into account in future studies.     

Short-term testing of antifouling surfaces: the importance of colour

Abstract

Data from short-term biofouling assays are frequently used to evaluate the performance of antifouling (AF) coatings. There are a large number of factors, however, that may influence community development. One such factor is colour. The hypothesis was that differences in colour may impact the short-term development of a biofouling community and therefore bias the results. An experiment was designed to investigate the effect of black and white substrata on settlement of fouling organisms in the field. Both Ulva sp. and Spirorbis sp. had significantly higher settlement on black surfaces. This result emphasises the importance of considering colour and other factors when undertaking short-term testing of AF coatings.     

Evaluation and recommendations for greater accessibility of colour figures in ornithology

People who are colour‐blind or have some form of colour vision deficiency form an invisible minority and scientists should strive to be as inclusive as possible. We reviewed 2873 figures published in 2019 from 1031 scientific papers in 27 ornithological journals to determine those that were colour‐blind compatible, and those that were black‐and‐white printer friendly. About 26% of the published figures were in colour, and while most were colour‐blind compatible, only ~ 60% of them were black‐and‐white printer friendly. Ensuring figures in all forms of scientific communication can be interpreted by readers who are colour‐blind, and can be printed in black‐and‐white will improve the accessibility of ornithological research.     

A review of melanized (black) fungal contamination in pharmaceutical products—incidence,drug recall and control measures

The aim of this study was to describe the incidence of contamination of pharmaceutical products by melanized fungi and to consider control measures in relation to bioburden and cleanrooms. This study reviews and analyses pharmaceutical product recalls and offers incidence rates of fungal detection from a typical cleanrooms. The recalls include some serious cases which resulted in the loss of life. Of different types of fungal contamination incidences some of the most damaging have been due to melanized fungi (‘black mould’), such as Exserohilum rostratum. The focus of the article is with melanized fungi. The study concludes that, from the review of recent pharmaceutical product recalls, fungal contamination is either increasingly common within cleanroom environments or the accuracy of sampling and the level of reporting has risen. The prevalence of melanized fungi in pharmaceutical facilities rests on specific virulence factors particular to these types of fungi, which are outlined. The article identifies a gap in the way that such fungi are screened for using available cultural methods. The article provides some control strategies, including assessing the suitability of disinfectants and biocides, for reducing the risk of melanized fungal incidences within the pharmaceutical facility. Understanding the fungal risk to pharmaceutical products remains a poorly understood and often overlooked aspect of pharmaceutical microbiology. This article helps to identify this risk and offer some guidance to those involved with pharmaceutical products manufacture in relation to bio‐contamination control strategies.     

Metabolic mapping of proteinase activity with emphasis on in situ zymography of gelatinases: review and protocols.

Proteases are essential for protein catabolism, regulation of a wide range of biological processes, and in the pathogenesis of many diseases. Several techniques are available to localize activity of proteases in tissue sections or cell preparations. For localization of the activity of matrix metalloproteinases, in situ zymography was introduced some decades ago. The procedure is based on zymography using SDS polyacrylamide gels containing gelatin, casein, or fibrin as substrate. For in situ zymography, either a photographic emulsion containing gelatin or a fluorescence-labeled proteinaceous macromolecular substrate is brought into contact with a tissue section or cell preparation. After incubation, enzymatic activity is revealed as white spots in a dark background or as black spots in a fluorescent background. However, this approach does not allow precise localization of proteinase activity because of limited sensitivity. A major improvement in sensitivity was achieved with the introduction of dye-quenched (DQ-)gelatin, which is gelatin that is heavily labeled with FITC molecules so that its fluorescence is quenched. After cleavage of DQ-gelatin by gelatinolytic activity, fluorescent peptides are produced that are visible against a weakly fluorescent background. The incubation with DQ-gelatin can be combined with simultaneous immunohistochemical detection of a protein on the same section. To draw valid conclusions from the findings with in situ zymography, specific inhibitors need to be used and the technique has to be combined with immunohistochemistry and zymography. In that case, in situ zymography provides data that extend our understanding of the role of specific proteinases in various physiological and pathological conditions.