Search Results (47)

Black crust and spalling are common deterioration phenomena affecting marble relics, yet their correlation remains inadequately understood. Hyperspectral imaging, reflectance spectroscopy, portable X-ray Fluorescence (p-XRF), infrared thermography, Scanning Electron Microscopy coupled with Energy-Dispersive Spectroscopy (SEM-EDS), and microbiological analysis was employed to connect these two types of deterioration on the Danbi stone carving of the Confucian Temple in Beijing. Spectral and thermal analyses reveal that black crust significantly reduces reflectance and increase solar absorption by 27%, resulting in thermal stress. p-XRF and SEM-EDS analyses indicated that black crust is enriched in Fe, Ti, Zn, Pb, As and clay minerals, while spalling areas display increase Ca, reflecting substrate exposure. Microscopy reveals microcracks at the layer–substrate interface. Microbiological analyses identify Cladosporium anthropophilum and Alternaria alternata as contributors to surface-darkening. These multi-scale datasets collectively demonstrate that alterations in surface chemistry and bio-mediated darkening promoting the formation of black crusts, which subsequently induce marble spalling due to solar absorption and thermal stress. These findings clarify the coupled physical–chemical–biological pathways through which black crust accelerates stone spalling. Full article

This work presents a multifactorial strategy for reusing waste thermoplastics and generating multifunctional filaments for additive manufacturing. Acrylonitrile–butadiene–styrene (ABS) waste and commercial poly(methyl methacrylate) (PMMA) were compounded with carbon black (CB), graphene (G), or graphene foam (GF) at different loadings and extruded into composite filaments. The aim is to couple filler-induced bulk modifications with atmospheric pressure plasma jet (APPJ) surface coatings of TiO₂ and graphene oxide (GO) to obtain waste-derived filaments with tunable morphology, wettability, and thermal stability for advanced 3D-printed architectures. The filaments were subsequently coated with TiO₂ and/or GO using an APPJ process, which tailored surface wettability and enabled the formation of photocatalytically relevant interfaces. Digital optical microscopy and SEM revealed that CB, G, and GF were reasonably well dispersed in both polymer matrices but induced distinct surface and cross-sectional morphologies, including a carbon-rich outer crust in ABS and filler-dependent porosity in PMMA. For ABS composites, static contact-angle measurements show that APPJ coatings broaden the apparent wettability window from ~60–80° for uncoated filaments to ~40–50° (TiO₂/GO) up to >90° (GO), corresponding to a ≈150% increase in contact-angle span. For PMMA/CB composites, TiO₂/GO coatings expand the accessible contact-angle range to ~15–125° while maintaining surface energies around 50 mN m⁻¹. TGA/DSC analyses confirm that the composites and coatings remain thermally stable within typical extrusion and APPJ processing ranges, with graphene showing only ≈3% mass loss over the explored temperature range, compared with ≈65% for CB and ≈10% for GF. Fused deposition modeling trials verify the printability and dimensional fidelity of ABS-based composite filaments, whereas PMMA composites were too brittle for reliable FDM printing. Overall, combining waste polymer reuse, tailored carbonaceous fillers, and APPJ TiO₂/GO coatings provides a versatile route to design surface-engineered filaments for applications such as photocatalysis, microfluidics, and soft robotics within a circular polymer manufacturing framework. Full article

Black crusts are degradation features found on stone buildings, offering valuable insights into local pollution sources. Their composition and structure reflect environmental conditions, making them important indicators for environmental and conservation studies. In this study, black crusts collected from funerary monuments in the Monumental Cemetery of Milan were comprehensively characterized using SEM-EDX, Raman spectroscopy, LIBS, and oxidative potential (OP) assays. SEM-EDX and Raman spectroscopy revealed extensive degradation of the substrate and the incorporation of pollutant-derived particles, with heavy metals such as Fe, Zn, and Pb detected in more than 90% of the samples. Correlation analysis proved effective in distinguishing major pollution sources, primarily vehicular and railway traffic, indicated by strong associations such as Zn–Mn (r = 0.896), Fe–Zn (r = 0.734), and Fe–Mn (r = 0.655), from minor sources linked to industrial emissions, reflected in correlations including Ti–Pb (r = 0.589), Pb–Cl (r = 0.702), and S–Pb (r = 0.661). Instead, LIBS analysis confirmed stratigraphic penetration of these elements beyond the surface layers, suggesting long-term accumulation. OP assays, applied here for the first time to black crusts, showed values between 0.5 and 3.0 pmol min⁻¹ µg⁻¹, indicating moderate oxidative reactivity linked to metal content. Overall, the findings contribute to a deeper understanding of pollution-driven stone decay and support the development of more effective diagnostic and conservation strategies. Full article

Black crusts and biological colonisation are among the most common types of ‘diseases’, with diverse aetiologies and presentations, affecting masonry architectural heritage. Over the past decades, there has been an increase in the incidence of this degradation phenomena due to the increase in pollution and climate change, especially on the urban walls of ancient cities. In particular, the present research examines the state of conservation of the city walls of Perugia, which are divided into two main city walls dating back to the Etruscan and Medieval periods and are recognised as historical heritage of high identity and cultural value. The degradation reflects, in the mentioned cases, on the liminal public and green areas. A view is also reflected in local journalism and social media, where residents and visitors have framed the spontaneous growth of herbs and medicinal shrubs within the stone joints of historic walls as an apparently benign and aesthetically pleasing occurrence. This misleading interpretation, while rooted in a superficial aesthetic appreciation, nevertheless draws attention to a real and urgent issue: the pressing need for systematic maintenance and intervention strategies—coordinated between academics, students, designers and stakeholders—which are able to reposition the city walls as central agents of urban and cultural regeneration, rather than peripheral remnants of the past. Full article

Urban air pollution poses significant risks to cultural heritage buildings, particularly in polluted megacities like Delhi, India. The Red Fort, a UNESCO World Heritage Site and a symbol of India’s rich history, is highly susceptible to degradation caused by air pollutants. Despite its great importance as an Indian and world heritage site, no studies have focused on characterizing its constituent materials or the degradation phenomena taking place. This study was developed in the framework of the MAECI (Italian Ministry of Foreign Affairs) and the Department of Science and Technology under the Ministry of Science and Technology, India, project: Indo—Italian Centre of Excellence for Restoration and Assessment of Environmental Impacts on Cultural Heritage Monuments. To understand their composition and degradation, Vindhyan sandstone and black crust samples were studied. Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) indicated that the red sandstone predominantly consisted of quartz and microcline, while the black crusts mainly comprised gypsum, bassanite, weddellite, quartz, and microcline. The analysis attributed the formation of gypsum to exogenous sources, such as construction activities and cement factory emissions. This pioneering study provides a basis for further research into the impacts of air pollution on Indian patrimony and promotes conservation strategies. Full article

A diagnostic chemical analysis has been performed on a Roman Cippus funebris in precious white marble located close to an ancient Roman road. The Cippus was in good condition but almost completely covered by a black patina, requiring a conservative cleaning intervention. The restorer in charge of the restoration asked us to make a preliminary diagnosis, on the basis of which we could suggest the most appropriate intervention. The Cippus was dedicated to the young Quintus Cornelius Proclianus, who died at the age of 15, by his mother Valeria Calpurnia Scopele. It perfectly fits into the Roman funerary liturgy and also shows an Etruscan-type iconography that seems to confirm the Etruscan Gens of the family and its dating to the 1st century AD. Ion chromatography (IC) analyses were performed to determine anions and cations on solutions obtained from the extraction of salts from the four samples of the Cippus. pH, conductivity, and red-ox potential measures, as well as UV-visible spectra were carried out on the same solutions. A small fragment, spontaneously fallen from the Cippus’ surface, was also observed by optical microscopy (OM) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). From the analyses, the dark patina that covered the surface before cleaning turned out to be made of black crusts, that is, smog particles adsorbed on sulfates, but above all, by a layer of microflora. The results allowed us to suggest some conservative interventions. Full article

The deterioration of stone heritage in urban environments is mainly the product of sources of air pollution like vehicular traffic and domestic heating. The results of these phenomena usually manifest as acid rain and particulate patinas, acting on the surface of stone monuments to form the so-called “black crusts”, a typical stone degradation product, mainly composed of gypsum. The aims of this study were to investigate the extent of these phenomena on the decorative apparatus of the frontal façade of Gesù Nuovo Church, in the historical centre of Naples (Italy). Preliminary diagnostics consisted of XRD and FTIR to analyse the composition of stone materials and inquire about previous restorations. The chemical characterization of black crusts was performed, using a diverse array of techniques, to highlight how different compounds are distributed along a vertical gradient and considering the proximity of specific sources of pollution (vehicle engine ignition, incense combustion, domestic heating products). Finally, molecular biology techniques were employed to identify the organisms which typically dwell in this formation and speculate about their contribution to the degradation of stone. Full article

Calcareous stones, such as marble and limestone, have been widely used in ancient architecture due to their durability, abundance, and ease of extraction and workability. However, their chemical nature renders them vulnerable to atmospheric pollutants. With industrialization and socio-economic growth, air pollution has severely impacted built heritage, including numerous historical buildings and monuments, particularly under changing climate and environmental conditions. Various forms of degradation, such as acid corrosion, mineral crystallization, and black crusts, are widespread and typically driven by atmospheric pollutants like sulfur dioxide (SO₂), nitrogen oxides (NO_X), ozone (O₃), and particulates (PM), which accelerate the deterioration of stone surfaces. To develop sustainable mitigation strategies, it is essential to gain an in-depth understanding of these deterioration mechanisms and current technological advancements. This paper first reviews the influencing factors and underlying mechanisms of atmospheric deterioration of calcareous stones. Subsequently, it discusses the advantages and limitations of traditional and advanced conservation and restoration techniques at the micro-level, as well as pollution management strategies that can be adopted. Finally, the challenges of research in this field are highlighted, and directions for the sustainable conservation of calcareous stones are proposed. Full article

The black skimmer (Rynchops niger) is a state-threatened, colonially nesting seabird in Florida, USA. Conservation threats include habitat alteration, human disturbances, severe weather, and predation. During nest monitoring (May–September, 2020–2022), black skimmer juveniles at colonies on Fort Myers Beach and Marco Island, Florida, had polyarthritis and died or were euthanized due to severe illness. Similarly-aged skimmers from geographically distant (considered unaffected) colonies were evaluated for comparison (2021–2023). We documented field, clinical, radiographical, and pathological findings to characterize disease and purported pathogenesis. The majority were lame and lethargic, in poor nutritional condition, and dehydrated. Additionally, 8/23 of the skimmers with dermatitis and arthritis from affected colonies also had penetrating sandspurs associated with skin ulceration, scabbing, and/or hemorrhage. The affected joints were often in limbs (interphalangeal and hock; less commonly stifle, elbow, carpus). A postmortem evaluation and bacteriology revealed Staphylococcal aureus-associated dermatitis, arthritis, tenosynovitis, and/or osteomyelitis in 21/22 of the juvenile skimmers from southwestern nest colonies. Staphylococcus aureus dissemination to internal organs occurred in 10/13 of the skimmers tested. Among skimmers evaluated from distant colonies, 5/10 that were examined histologically had skin crusting and inflammation but lacked arthritis. Occasional coinfections were documented (e.g., West Nile virus, Gram-negative bacilli). The results suggest that staphylococcal joint disease originated from sandspur-induced skin damage, followed by hematogenous dissemination to the joints and, occasionally, the internal organs. Additional nest sites should be tested to evaluate disease risk and potentially contributing environmental factors. We recommend that site managers employ techniques that reduce the risk of skimmer interactions with sandspurs. Full article

The Quaternary Mercure basin is a complex fault structure located in the Pollino region of the southern Apennines (Italy). A persistent seismic gap makes the Mercure basin structure one of Italy’s highest seismic risk zones. The southernmost termination of the Mercure basin is the Timpa della Manca fault. The fault’s mirror is characterised by distinctive, lineated, black-coloured striae decorating a cataclasite made of carbonate clasts. These black-coloured striae consist of a mixture of Mn phases, including hollandite, todorokite, birnessite, and orientite, which are associated with goethite and hematite along with minor amounts of phyllosilicates (chlorite, muscovite), quartz, and sursassite. This mineral association and their phase stability suggest that hydrothermal circulating fluids may have mobilised and re-precipitated low-temperature Mn hydrous phases within the shear zone, leaving remnants of higher-temperature minerals. Oceanic crust remnant blocks within the Frido Unit appear to be the most likely source of the Mn. The uniqueness of the Mn striae on the Timpa della Manca fault offers intriguing insights into fluid circulation within the Mercure basin tectonic system, with potential implications for the seismotectonic characteristics of the Pollino region. Full article

Using plant extracts to replace traditional chemical herbicides plays an essential role in sustainable agriculture. The present work evaluated the quality of durum wheat cv Valbelice in two years (2014 and 2016) using plant aqueous extracts of sumac (Rhus coriaria L.) and mugwort (Artemisia arborescens L.) as bio-herbicides on the main quality characteristics of durum wheat. The untreated, water-treated, and chemically treated durum wheat products were also analyzed as controls. Following the official methodologies, grain commercial analyses and defects of the kernels were determined. The main chemical and technological features were determined on the wholemeal flour: proteins, dry matter, dry gluten, gluten index, colorimetric parameters, mixograph, falling number, and sedimentation test in SDS. An experimental bread-making test was performed, and the main parameters were detected on the breads: bread volume, weight, moisture, porosity, hardness, and colorimetric parameters on crumb and crust. Within the two years, grain commercial analyses of the total five treatments showed no statistically significant differences concerning test weight (range 75.47–84.33 kg/hL) and thousand kernel weight (range 26.58–35.36 kg/hL). Differently, significant differences were observed in terms of kernel defects, particularly starchy kernels, black pointed kernels, and shrunken kernels, mainly due to the year factor. Analyses on the whole-grain flours showed significant differences. This affected dry gluten content (7.35% to 16.40%) and gluten quality (gluten index from 6.44 to 45.81). Mixograph results for mixing time ranged from 1.90 min to 3.15 min, whilst a peak dough ranged from 6.83 mm to 9.85 mm, showing, in both cases, statistically significant differences between treatments. The falling number showed lower values during the first year (on average 305 s) and then increased in the second year (on average 407 s). The sedimentation test showed no statistically significant differences, ranging from 27.75 mm to 34.00 mm. Regarding the bread produced, statistically significant year-related differences were observed for the parameters loaf volume during the first year (on average 298.75 cm³) and then increased in the second year (on average 417.33 cm³). Weight range 136.85 g to 145.18 g and moisture range 32.50 g/100 g to 39.51 g/100 g. Hardness range 8.65 N to 12.75 N and porosity (range 5.00 to 8.00) were closely related to the type of treatment. Finally, the color of flour and bread appeared to be not statistically significantly affected by treatment type. From a perspective of environmental and economic sustainability, the use of plant extracts with a bio-herbicidal function could replace traditional chemical herbicides. Full article

The objective of this work was to evaluate the development of Davidiella sp. and its asexual form, Cladosporium sp., under different environmental conditions in the rubber tree (Hevea brasiliensis). Rubber tree leaves were inoculated with a spore suspension and kept in a humid chamber under different temperatures and wetness periods. The behavior of the fungi was evaluated using a scanning electron microscope (SEM) and an ultraviolet light microscope (UV). In the images obtained in SEM, four hours after inoculation of the fungus, it was possible to verify the germination and penetration of conidia at temperatures of 10 to 20 °C. The formation of conidiophores was verified from six hours after inoculation, indicating that it is in the reproductive period. In the sexual phase, in SEM, from four hours after inoculation, it was possible to verify the formation of small protuberances at temperatures between 10 and 20 °C. These black dots evolve into circular, protruding black spots, like the symptoms of black crust, with apparent spore formation on them. The data obtained from the UV analyses corroborate those from SEM, showing that the fungus has good development in its two phases between temperatures of 20 and 25 °C and that the period of wetness on the leaf can contribute to the initial development of the pathogen. Full article

The study is focused on the analysis of black crust and soiling on the building materials of the medieval Lipowiec Castle in southern Poland. The castle was constructed using local, partly dolomitic limestones and dolomites, supplemented with other limestones and bricks, during 20th-century renovations of the castle ruins. The crust and soiling components, secondary mineral phases, and particulate matter of anthropogenic origin were analysed using Raman micro-spectroscopy (RS) and scanning electron microscopy coupled with energy-dispersive spectrometry (SEM-EDS). The crust, mostly composed of gypsum and other sulphate phases, was found to contain carbonaceous matter, spherical Si-Al glass particles, and iron oxides, with admixtures of other elements, including heavy metals, as well as irregularly shaped particles containing various metals. These components reflect the air pollution in the region, related to the combustion of solid fuels in both industrial power plants and local domestic furnaces, Zn-Pb ore mining (operational until 2021), and smelting in the neighbouring industrial centre. Despite its location in a rural area, the castle has been exposed to pollution for an extended period due to its proximity to large industrial centres. Therefore, the crust analysed may serve as an environmental indicator of the nature of the air pollution in the region. Full article

The diversity in the global food market is expanding as thousands of new products enter the business every year, among which nutraceutical and functional foods hold important positions. The present research work aimed at the nutritional evaluation of three medicinal herbs, i.e., turmeric (Curcuma longa L.), ginger (Zingiber officinale), and black cumin (Nigella sativa). A bread formulation was enriched with the individual/combined supplementation (1–3%) of these herbs. Later, the bread was analyzed for nutritional, rheological, textural, and sensorial characteristics. The results revealed that the herbs improved the nutritional composition of bread, especially ash and fiber, as the maximum ash and fiber contents were noticed in T₁₅ (2.0% dried powder of each plant) with values of 1.64 ± 0.04% and 4.63 ± 0.16%, respectively. The results regarding the rheological behavior showed minor variations in the rheological traits and a slight increase in dough development time up to 4.50 ± 0.20 min in T₁₀ from 2.80 ± 0.13 min in T₀. The sensorial attributes also indicated their marked suitability as external and internal characteristics were least affected by the addition of the herbs. Although some parameters like the crust and crumb colors were affected by the addition of black cumin, showing values of 6.25 ± 0.52 and 4.44 ± 0.19, respectively, in T₁₅, and aroma characteristics were affected by the addition of ginger, supplementation with a combination of herbs at lower doses mitigated the adverse effects of other herbs. Moreover, shelf-life extension, especially with the addition of turmeric powder, was the hallmark of this research. This study concluded that medicinal herbs can be incorporated into baked products to improve the nutritional and sensorial attributes of functional herbal bread. Full article

Tinea capitis is a dermatophyte scalp infection with a marked prevalence among the pediatric population. However, in the last few years, its epidemiology has changed due to increasing population migration worldwide. Host-specific and environmental factors contribute to the pathogenesis of tinea capitis. Clinically, tinea capitis may present as a subtle hair loss accompanied by scalp scaling, alopecia with scaly patches, or alopecia with black dots. A more severe form of tinea capitis is represented by kerion celsi, which clinically presents as a tender plaque covered by pustules and crusts. If left untreated, this dermatophytic infection may resolve with permanent scarring and alopecia. The pathological changes found in tinea capitis are reflected by a spectrum of clinical changes. Zoophilic infections typically prompt an extensive inflammatory reaction, while anthropophilic dermatophytoses often lack inflammation and result in more persistent lesions. Tinea capitis typically requires systemic antifungal therapy. Griseofulvin, terbinafine, itraconazole, and fluconazole are the main antifungal agents used. Currently, the duration of antifungal therapy varies based on the clinical presentation and type of dermatophyte involved. Through the reported cases and literature review, we aim to emphasize the importance of the early recognition of atypical variants of tinea capitis in immunocompetent children for the prompt initiation of systemic antifungal therapy, minimizing the need for prolonged treatment. Additionally, we emphasize the importance of regular laboratory testing during systemic antifungal therapy, particularly liver enzyme tests, to prevent adverse events, especially in cases requiring long-term treatment. Full article