Search Results (51)

Compact carbonate stones are widely used in architectural heritage for their aesthetic value and cultural significance, yet their long-term durability in saline environments remains insufficiently understood, particularly when assessed using standard salt crystallization tests developed primarily for porous lithotypes. This study investigates salt-induced deterioration in Portoro limestone, a compact ornamental carbonate extensively employed in historic architecture, considering four commercial varieties representative of heritage applications. Salt crystallization tests were performed using saturated sodium sulphate (Na₂SO₄) and sodium chloride (NaCl) solutions following the relevant European standard procedure, with the protocol extended to 45 cycles to capture delayed deterioration processes. Both untreated specimens and samples subjected to controlled thermal pre-conditioning at 300 °C and 500 °C were tested to activate latent microstructural weaknesses. Material decay was assessed through mass variation, porosity changes, surface observations, Leeb rebound hardness and ultrasonic pulse velocity measurements. Results demonstrate that deterioration is primarily controlled by salt type and microstructural characteristics rather than by total porosity. Sodium sulphate induced severe internal damage and abrupt structural failure associated with mirabilite crystallization, often following a prolonged phase of apparent stability. In contrast, sodium chloride causes mainly superficial effects with negligible mechanical impact. Thermal pre-conditioning accelerated damage development, while non-destructive techniques revealed internal deterioration well before visible damage occurred. These findings indicate that standard crystallization tests may be inadequate for low-porosity stones and that extended-cycle approaches provide a more reliable framework for durability assessment in saline environments. Full article

Considering the limitations of test samples for existing stone beams, the discreteness of stone constitutive relations, and the dimensional variability among test specimens, this study conducts a systematic investigation via finite element parametric analysis based on full-scale prototype tests. The research examines the effects of different reinforcement materials, reinforcement ratios (ρ), and reinforcement layer thicknesses (a_s) on the flexural performance and comprehensive benefits of non-destructive stone beam reinforcement. The results indicate that the type of reinforcement material significantly impacts the initial linear elastic stiffness, peak load, and residual load of the stone beams. The increase in peak load and the proportion of residual bearing capacity are more sensitive to the reinforcement ratio (ρ). Although increasing the reinforcement layer thickness (a_s) enhances the initial linear elastic stiffness, its influence on residual bearing capacity is complex. Among the specimens with reinforcement materials, carbon fiber-reinforced polymer (CFRP) mesh reinforcement exhibits superior performance in terms of both the energy dissipation evaluation indicator (T_E) and the comprehensive benefit evaluation indicator (R_TC). These findings provide a reliable basis for the design of stone beam strengthening and suggest that reinforcement materials, reinforcement ratios, and reinforcement layer thicknesses should be selected according to specific engineering requirements to achieve an optimal balance between reinforcement effectiveness and economic benefit. Full article

The prevention of trichinellosis is one of the most important tasks of the public veterinary services. In most EU countries, mandatory testing for parasites of the genus Trichinella includes domestic pigs as well as game species such as wild boar and bears. In Croatia, hunters occasionally also submit badger (Meles meles) meat for Trichinella testing. In addition to the samples from the genus Meles, samples from two other genera within the same family, Martes and Mustela, were analysed. These specimens were most frequently delivered to the laboratory, as roadkill, within a passive surveillance program for the rabies virus. During a 14-year study period, muscle samples from 40 badgers (M. meles), 11 martens (M. foina) and from one polecat (M. putorius) were examined using the artificial digestion method. Trichinella infection was confirmed in four badgers (10%) and one marten (9.1%). Molecular identification by multiplex PCR revealed T. spiralis and T. britovi in two badger specimens, while T. pseudospiralis was identified in a stone marten. Further genetic analysis of the T. pseudospiralis isolate demonstrated its belonging to the Palaearctic population. This study evaluates the epidemiological significance of these findings in relation to trichinellosis, the most important foodborne parasitosis in Croatia, and emphasizes the need for further epidemiological studies in the country targeting both Mustelidae and T. pseudospiralis in the sylvatic cycle of Trichinella. Full article

The building sector faces sustainability issues due to its substantial resource demand, prompting the exploration of alternative materials of natural origin. Given the diverse environmental conditions buildings experience, assessing the impact of these conditions on the mechanical characteristics of alternative materials becomes crucial. This study focuses on a composite comprising stone, agglomerate cork core and glass fiber-reinforced epoxy skins, designed for ventilated facades. The composite underwent an aging cycle commonly applied in the evaluation of construction building materials to evaluate its flexural behavior. To that end, bending tests on unaged and aged samples were carried out to investigate both the bending strength and stiffness. The composite panels were tested in two configurations: (i) stone facing up and (ii) stone facing down. The results indicated that higher bending strength was found in samples where the stone was facing up, regardless of the aging condition. In the stone facing up configuration, the predominant failure mode was stone crushing, whereas the samples in the stone facing down configuration evidenced a failure mechanism of fiber breakage. Despite the observed morphological differences between aged and unaged specimens, no significant difference was found regarding the bending strength and failure modes in both tested configurations. However, a flexural stiffness reduction of at least 21% was found for every aged specimen. Full article

This paper presents the results of a multidisciplinary research project carried out over the past two years by the Archaeological Mapping Laboratory at the CNR-ISPC, Lecce, and the Heritage Materials Science group at the CNR-ISPC, Florence, in collaboration with the PASAP Med Ph.D. Programme at the University of Bari “Aldo Moro”. The investigation focuses on stone procurement strategies employed by the Messapian settlement at Ugento, near the Ionian coast of Salento. Archaeological surveys within its territory and surrounding areas enabled the identification and petrographic characterization of ancient extraction sites, allowing for the classification of several calcarenite types. Systematic sampling and petrographic analyses of archaeological specimens shed light on the sourcing strategies adopted for both the construction of the city’s defensive walls—erected in the mid-4th century BCE—and selected architectural and sculptural elements preserved in the Ugento Archaeological Museum and the Colosso Collection, dating from the Archaic to the Hellenistic periods. The analyses show that the availability of lithotypes in the region significantly influenced construction techniques, particularly in the city walls, while in certain cases—such as specific architectural elements made of pietra leccese—it required the import of lithologies absent from the immediate vicinity. Full article

Identification of the strength characteristics of mortars in brick or stone masonry is crucial in the structural analysis of heritage buildings and selecting materials for their repairs and reconstruction. Non-destructive, minimally destructive, and minor-destructive tests have been developed to establish the strength of mortar in existing masonry. This paper presents strength tests on mortar samples extracted from bed joints of heritage buildings erected in the historic center of Cracow during the 19th and 20th centuries. The mortar samples were tested using the double-punch method, a minor-destructive technique especially useful for heritage structures where cutting out large masonry specimens is not possible due to conservation reasons. The impact of sample thickness and type of capping materials on the test results were analyzed in detail. Practical recommendations are also proposed for the procedure of the double-punch method in relation to historical mortars. Full article

This study investigates the mineralogical and physical properties of serpentinite from the Monteferrato area (Tuscany, Italy) to evaluate its potential use in Tuscany architectural restoration. The research addresses the need to identify replacement materials compatible with historic stones while preserving their original features. Representative specimens from the Bagnolo quarry were analysed through physical testing and a wide range of mineralogical and geochemical techniques, including polarised light microscopy, X-ray diffraction, electron probe micro-analysis, whole-rock chemistry, and fibre quantification. The results show a mineralogical composition dominated by serpentine-group minerals and magnetite, with physical properties generally consistent across samples. Measured capillary water absorption ranges from 3.27 to 5.27 g/m²·s^0.5, open porosity from 5.25% to 8.93%, apparent densities range from 2.49 to 2.56 g/cm³, and imbibition coefficient from 2.16% to 3.71%. Comparative analysis with serpentinite from historic sources (Figline di Prato quarry, Tuscany) and from monuments (Baptistery of San Giovanni, Florence) demonstrates close compositional and textural affinities, supporting the suitability of the rock from the studied quarry for restoration purposes in Tuscany monuments. However, chrysotile concentrations up to 14,153 mg/kg, exceeding Italian regulatory thresholds, represent a critical limitation. This not only requires the implementation of strict safety measures but also raises serious concerns regarding the practical feasibility of using this stone in conservation projects. More broadly, the presence of asbestiform minerals in serpentinites highlights a significant and often underestimated health risk associated with their extraction, processing, and use. Despite its importance, detailed fibre count data are rarely published or made publicly accessible, hindering both transparent risk assessment and informed decision-making. By integrating petrographic, mineralogical, and physical–mechanical characterisation with fibre quantification, this study not only assesses the technical suitability of Monteferrato serpentinites for restoration of Tuscan monuments but also contributes to a more responsible and evidence-based approach to their use, emphasising the urgent need for transparency and health protection in conservation practices. Full article

This paper presents the results of a research project on the use of stone in Roman architecture in Oderzo and Concordia Sagittaria, located between the Tagliamento and the Piave rivers (Italy). The study involved a documental survey, material sampling and analysis, provenance identification, and interpretation of results to reconstruct ancient stone trade routes. During sampling, 33 carbonate rock specimens were collected from archaeological sites and architectural elements in Oderzo, and 52 from Concordia Sagittaria. In both cities, these rocks were primarily used for architectural elements such as columns and capitals, whereas these lithotypes were less frequently employed in structures and infrastructures. The analysis revealed a significant reliance on regional limestones. Petrographic examinations (PLM-TL) identified six main limestone groups, many of which were linked to quarries located in the Aurisina and in the Triestine Karst region, as well as in the Prealps and Berici Hills. The study encountered several challenges: many analysed samples displayed petrographic characteristics consistent with multiple sources, complicating the precise identification of their extraction site. Despite a detailed understanding of the region’s geology, reference geological datasets often overlook outcrops that may have been exploited in antiquity. Consequently, when samples lacked distinctive features, tracing them to a particular quarrying basin proved difficult. In conclusion, the research underscores the extensive use of local limestones while acknowledging the challenges posed by limited petrographic reference data, which hinder the precise identification of the source basins of the materials used in Roman construction. Full article

Background: Gallstone ileus is a rare cause of bowel obstruction, often presenting with nonspecific symptoms that delay diagnosis. This study assessed the diagnostic value of CT imaging and its correlation with histopathological findings in confirmed cases. Methods: A retrospective analysis of 14 patients with surgically confirmed gallstone ileus was performed. All underwent abdominal radiography, ultrasound, and CT. Imaging findings were evaluated for calcification type, impaction site, and fistula presence. Histopathology from surgical specimens was used for correlation. Relative risk (RR) and 95% confidence intervals (CIs) were calculated, with adjustments for small sample size. Results: Rim-calcified gallstones were the most common (50%) and significantly associated with chronic inflammation (RR 1.42, 95% CI: 1.05–1.93). Cholecystoduodenal fistulas were most frequent (57.1%), with a 92.8% imaging-pathology concordance. Ileal impaction (35.7%) was linked to increased risk of bowel necrosis (RR 2.0, 95% CI: 1.1–3.6). All stones were >3 cm; two patients had recurrence. No perioperative mortality occurred. Conclusions: CT imaging demonstrates high diagnostic accuracy and strong correlation with histopathological findings in gallstone ileus. Identifying calcification patterns and impaction sites aids early diagnosis and surgical planning. Full article

Because of their diversity, microplastics (MPs), which are synthetic particles smaller than 5 mm, are highly bioavailable and widely distributed. The prevalence of microplastics in aquatic habitats has been extensively studied but less is known about their presence in terrestrial environments and biota. This study examined MP intake in terrestrial environments utilizing gastrointestinal tracts (GITs), with a particular focus on the Turkish worm lizard (Blanus strauchi). Suspected particles discovered in the GITs were removed, measured, and characterized based on size, shape, color, and polymer type in order to evaluate MP ingestion. Out of 118 samples analyzed, 29 specimens (or 24.57%) had microplastic particlesMP length did not significantly correlate with snout–vent length (SVL) and weight. These correlations were tested to determine whether the size or weight of Blanus strauchi influenced the amount or size of MPs found within the GITs. Also, MP consumption by the worm lizard did not correlate with the year of sampling. All particles identified as fibers through FT-IR spectroscopy analysis. The most common type of microplastic was polyethylene terephthalate (PET). The most often detected color was blue, with mean MP lengths ranging from 133 µm to 2929 µm. It has been demonstrated that worm lizards inhabiting soil or sheltering under stones in bushy areas with sparse vegetation consume MPs. Predation is regarded to be the most likely way through which MPs infiltrate terrestrial food webs. Full article

The timing, cause, and magnitude of mammalian extinctions during the African Middle Pleistocene remain largely unresolved. The demise of Elephas/Palaeoloxodon recki, a lineage that had a great geographic and temporal span, represents a particularly enigmatic case of megafaunal extinction. Previous studies of Early Pleistocene fossil material have proposed that this lineage was a strict C₄-grazer, with its dietary specialization causing its extinction during a period of climatic instability that coincided with the Late Acheulean. Others have associated its disappearance with overhunting by hominins during the same period. We contribute to this debate by analyzing carbon and oxygen isotope data from the tooth enamel of late Early and Middle Pleistocene Palaeoloxodon specimens from various localities in the Afar Rift. To contextualize the isotopic data of Palaeoloxodon within its broader ecosystem, we also provide data from non-elephant species. Carbon isotope values indicate that while C₄ plants dominated diets, varying amounts of C₃ vegetation were also consumed throughout this period. Oxygen isotope values reflect an initial focus on stable water sources that were later broadened to include transient sources. Serially sampled teeth of P. cf. recki recki from Late Acheulean contexts in the Megenta research area show no significant seasonal shifts in δ¹³C or δ¹⁸O values, even during a period of heightened climatic instability regionally. Taken together, our results suggest that Palaeoloxodon was capable of flexibility in diet and drinking habits which belies its morphological specializations. Our results do not support the idea that an inability to adapt to climatic instability caused the extinction of P. recki recki during the Late Acheulean. There is also currently no solid evidence that hominin hunting activities were the cause. However, we cannot discount the potential cumulative impact of climatic-induced environmental pressures and advancements in hominin hunting technologies during the early Middle Stone Age on the eventual extinction of the Palaeoloxodon lineage during the Middle–Late Pleistocene interface. Full article

Spotted stone loach (Triplophysa strauchii), a common fish species in Xinjiang, China, is ecologically pivotal within the local ecosystem; regrettably, human-induced factors like habitat destruction, pollution, and overfishing have gravely imperiled its survival, and compounding this is the dearth of research on the morphological disparities among its geographically diverse populations. Thus, between April and October 2024, 198 specimens were procured from Sayram Lake, Khamusigou Reservoir, and Chaiwopu Lake using cage traps and gillnets; post-collection, an array of morphological metrics were meticulously measured, and then statistical methods such as one-way analysis of variance (ANOVA), principal component analysis (PCA), stepwise discriminant analysis, and cluster analysis were employed for comprehensive data interrogation. Findings show that, across all sampled populations, the mean values of the total length (X1), body length (X2), body height (X3), and body width (X4) of the Chaiwopu Lake population are significantly lower than those of the Sayram Lake population and the Khamusigou Reservoir population; except for head length, the Khamusigou Reservoir population has lower variability in other morphological traits compared to the others. Moreover, significant divergences were detected in multiple trait ratios among the populations; PCA yielded five principal components, cumulatively accounting for 77.45% of the total variance, spotlighting the key ratios; discriminant analysis further validated highly significant morphological distinctions (p < 0.01), with the Khamusigou Reservoir population having the highest discriminant accuracy; cluster analysis graphically showed the Sayram Lake and Chaiwopu Lake populations clustering together while the Khamusigou Reservoir population formed a separate cluster; and the Chaiwopu Lake population had the most pronounced divergence in morphological traits. This research not only provides novel perspectives on the adaptive evolutionary mechanisms of T. strauchii but also serves as a cornerstone for formulating evidence-based conservation and management strategies for this species. Full article

Esthetically pleasing temporary prostheses are often necessary for extended periods in a variety of clinical scenarios. Adjustments to the occlusion or margins are commonly needed before cementing the temporary prosthesis. Therefore, it is clinically necessary to repolish the rough surface to avoid biological and esthetic issues associated with rough surfaces. The purpose of this in vitro study was to assess and compare the impact of various polishing protocols on the surface roughness and color stability of three resin materials used for provisional crowns. A total of 150 specimens were fabricated from auto-polymerizing polymethyl methacrylate, bis-acryl composite, and Methyl methacrylate-LC resin using a stainless steel mold. Each material group was divided into five groups (n = 10) based on the applied surface treatment: positive control group (G1): no roughening or surface treatment, Negative control group (G2): acrylic bur-roughened surface without any polishing, the different surface treatment groups of silicon carbide and aluminum oxide stone polishing (G3), diamond-coated rubber twist (G4), and Surface Glaze (G5). An optical profilometer was used to assess the surface roughness of all samples. After undergoing 6000 cycles of thermocycling followed by immersion in a coffee solution for 15 days at 37 °C, color parameters were measured using a spectrophotometer both before and after a storage period to evaluate color differences. A two-way ANOVA test with α = 0.05 significance level was carried out to determine the impacts of both the materials utilized and the polishing protocol. Among the three types of resin examined, the bisacryl group exhibited superior surface quality in positive control groups, while PMMA resin demonstrated higher polishability. The diamond-coated rubber twits resulted in lower Ra values of 0.36 (0.01) µm, 0.52 (0.11) µm, and 0.28 (0.05) µm for PMMA, BAMA, and MMLC resins, respectively. The application of photo-polymerized surface glaze led to a plaque accumulation threshold of 0.2 µm across all resin groups. The greatest mean color change occurred in the negative control group, indicating a propensity for more staining on rougher surfaces. The Bisacryl resin exhibited higher ΔE values, whereas PMMA showed better color stability. The lowest ΔE values were found when the surface glaze was applied to all of the provisional crown resins. Untreated Bisacryl resin exhibited the lowest Ra values, while PMMA resins demonstrated superior surface morphology after polishing. PMMA provisional crown resins showed increased resistance to staining. The use of surface glaze enhanced both smoothness and color stability on the surfaces. Full article

Most historical buildings and structures in Oman were built using unreinforced stone masonry. These structures have deteriorated due to the aging of materials, environmental degradation, and lack of maintenance. This research investigates the physical, chemical, and mechanical properties of the local building materials. It also presents the findings of an experimental study on the in-plane shear effectiveness of a modern strengthening technique applied to existing stone masonry walls. The technique consists of the application of a textile-reinforced mortar (TRM) on one or two faces of the walls. Shear loading tests of full-scale masonry samples (1000 mm width, 1000 mm height, and 350 mm depth) were carried out on one unreinforced specimen and six different cases of reinforced specimens. The performances of the unreinforced and reinforced specimens were analyzed and compared. We found that strengthened specimens can resist in-plane shear stresses 1.5–2.1 times greater than those of the unreinforced specimen; moreover, they demonstrate ductility rather than sudden failure, due to the presence of fiberglass and basalt meshes, which restrict the opening of cracks. Full article

In spite of the demonstrated efficacy of basalt stone powder as a cost-effective and readily available additive in enhancing the mechanical properties and durability of ordinary-weight concrete, its application in Structural Lightweight Concrete (SLWC) remains unexplored. This study introduced a mixing design for SLWC incorporating Light Expanded Clay Aggregates (LECAs) and basalt stone powder with a subsequent evaluation of its strength and durability characteristics. The experimental procedure involved creating various samples, considering differing proportions of cement, water, basalt stone powder, sand, LECA, superplasticizer, and aerating agent. The compressive strength and density of the 28-day-cured concrete specimens were determined. An optimal SLWC with a compressive strength of 42 MPa and a density of 1715 kg/m³ was identified. The flexural and tensile strength of the optimal SLWC exceeded those of ordinary-weight concrete by 6% and 3%, respectively. Further evaluation revealed that the optimal SLWC exhibited 1.46% water absorption and an electrical resistivity of 139.8 Ohm.m. Notably, the high porosity of LECA contributed to the low durability of SLWC. To address this, cost-effective external coatings of emulsion and fiberglass were applied to enhance the durability of the SLWC. Four coating scenarios, including one-layer bitumen, two-layer bitumen, three-layer bitumen, and three-layer bitumen with fiberglass, were investigated. The measurements of electrical resistance and compressive strength revealed that the use of three layers of emulsion bitumen and fiberglass improved the durability of the concrete by over 90% when the SLWC was exposed to severe chloride attack. Consequently, the durability of the SLWC with an external coating surpassed that of ordinary-weight concrete. Full article