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Background: The growing integration of digital technologies in orthodontics is shifting the orthodontic diagnosis and recordkeeping paradigm, replacing conventional plaster models with intraoral scanning and 3D photography. This study investigated the impact of orthodontic plaster models on orthodontic diagnosis and treatment planning decisions by orthodontists. Methods: Thirty-three orthodontists assessed six patients' records with different malocclusion cases. Each case was assessed twice by each orthodontist evaluating a case: the first evaluation with digital records without diagnostic casts and the second evaluation with the added diagnostic orthodontic plaster model. Diagnostic and treatment plan decisions for each malocclusion case were compared with and without the aid of the diagnostic orthodontic plaster models to assess the plaster model's impact on the treatment plan's soundness. Results: Statistically insignificant differences were found for the diagnoses and treatment plans with or without the aid of orthodontic plaster models. Intraclass correlation coefficients revealed agreement among orthodontists for both evaluated situations (0.685; p < 0.0001). Plaster models were found to significantly influence orthodontists' decisions about the need for surgical intervention (p = 0.026), but they did not significantly impact the overall malocclusion diagnostic classification nor the decision regarding the extent of treatment, whether comprehensive or limited (p = 0.146) and extraction versus non-extraction approaches (p = 0.266). Conclusions: These findings support the idea that digital record alternatives may be viable for orthodontic recordkeeping purposes. Within the limitations of this study, it can be concluded that the presence or absence of orthodontic plaster models does not significantly impact the orthodontic diagnosis or treatment planning process. [ABSTRACT FROM AUTHOR]

Objective: This study investigated how the number of images collected for digital measurements in dentistry affects accuracy compared with traditional methods. Methods: A Frasaco maxillary model was scanned using a SHINING 3D AutoScan-DS-MIX dental 3D scanner to create an STL file. The maxilla was molded 10 times using polyvinyl siloxane (Zhermack Elite HD+) to produce plaster models, which were scanned with the same reference scanner to generate 10 STL files. The Frasaco model was scanned 10 times, capturing images in intervals of 800–1000, 1000–1200, and 1200–1500 using a 3Shape TRIOS 3 intraoral scanner, creating additional STL files. These were analyzed with reverse engineering software. Results: The most accurate measurements were obtained using 1200–1500 images. Conventional impression techniques performed significantly worse. There was a significant difference between the groups Digital 1200–1500 and Plaster (p < 0.001) and between Digital 800–1000 and Plaster (p = 0.007). No significant difference was found when the digital groups were compared among themselves. There was also no significant difference between the Plaster and Digital 1000–1200 groups. To compare precision values that were normally distributed across three or more methods, a one-way ANOVA was used. Trueness values that were not normally distributed with three or more methods were compared employing the Kruskal–Wallis test. Conclusions: Different image counts affect digital measurement accuracy. The most accurate measurements were obtained when collecting 1200–1500 images. Conventional impression techniques were shown to perform significantly worse than digital impression. [ABSTRACT FROM AUTHOR]

Copyright of Österreichische Wasser- und Abfallwirtschaft is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chinese historical timber buildings are famous for their exquisite craftsmanship. In China, there are various climates with significant fluctuations throughout the year. As some buildings are designed with an open style, many wooden components are exposed to environments with drastic changes in humidity, and the moisture content inside the wood may fluctuate significantly with the changing environment. To protect these architectural heritages from damage, here, numerical simulations were conducted to evaluate the effect of periodic climate conditions on moisture transfer inside wooden components. Five representative cities in China were chosen for comparison, and the long-term variations and dynamic responses of moisture content to periodic climate conditions were investigated. The results show that the moisture content inside the wood varies from 5% to 20% across different cities and months. The plaster layer, made from a mixture of lime, hemp, animal blood, and tung oil, serves as a waterproof coating to prevent significant moisture gradients within the wood. It also reveals that the dynamic moisture response to the climate may pose threats to historical buildings. By analyzing the potential risks, such as mechanical properties, fungal attacks, and fire hazards, this paper provides suggestions for the preservation of timber buildings with different climates in China. [ABSTRACT FROM AUTHOR]

ABSTRACT Background/Objectives Materials and Methods Results Conclusion The use of different models for the fabrication of custom‐fit mouthguards (MTGs) can affect their final thickness, adaptation, and shock‐absorption properties. This study aimed to evaluate the adaptation, thickness, and shock absorption of ethylene‐vinyl acetate (EVA) thermoplastic MTGs produced using conventional plaster or three‐dimensional (3D) printed models.A typical model with simulated soft gum tissue was used as the reference model to produce MTGs with the following two different protocols: plast‐MTG using a conventional impression and plaster model (n = 10) and 3DPr‐MTG using a digital scanning and 3D printed model (n = 10). A custom‐fit MTG was fabricated using EVA sheets (Bioart) plasticized over different models. The MTG thickness (mm), internal adaptation (mm) to the typodontic model, and voids in the area (mm2) between the two EVA layers were measured using cone‐beam computed tomography images and Mimics software (Materialize). The shock absorption of the MTG was measured using a strain‐gauge test with a pendulum impact at 30° with a steel ball over the typodont model with and without MTGs. Data were analyzed using one‐way analysis of variance with repeated measurements, followed by Tukey's post hoc tests.The 3DPr‐MTG showed better adaptation than that of the Plast‐MTG at the incisal/occlusal and lingual tooth surfaces (p < 0.001). The 3DPr‐MTG showed a thickness similar to that of the Plast‐MTG, irrespective of the measured location. MTGs produced using both model types significantly reduced the strain values during horizontal impact (3DPr‐MTG 86.2% and Plast‐MTG 87.0%) compared with the control group without MTG (p < 0.001).The MTGs showed the required standards regarding thickness, adaptation, and biomechanical performance, suggesting that the number and volume of voids had no significant impact on their functionality. Three‐dimensional printed models are a viable alternative for MTG production, providing better adaptation than the Plast‐MTG at the incisal/occlusal and lingual tooth surfaces and similar performance as the MTG produced with the conventional protocol. [ABSTRACT FROM AUTHOR]

Objective Method Result Conclusion The principles of limb reconstruction are crucial for treatment success, but there is no unified standard for complex limb deformities. The aim of this study was to analyze the characteristics of the cases of post‐traumatic lower limb deformity and explore the new principle of limb reconstruction.A retrospective analysis was conducted of 148 patients with post‐traumatic lower limb deformity who underwent surgery from May 1978 to December 2023; 85 were males (57.4%) and 63 were females (42.6%); 65 cases of left side (43.9%), 79 cases of right side(53.4%), and 4 cases were on both sides (2.7%), the average age was 24.64 years (5–69). There were 4 cases suffering hip deformities, 40 cases of femoral deformities, 18 cases from knee, 40 cases from tibiofibular, 93 cases of foot and ankle deformities, and some patients also had two or more types. All patients underwent surgical intervention in an average of 40.5 months (12–96) after injury. According to the evaluation of limb deformities, deformity correction and functional reconstruction with external fixation were implemented, following the principle of “one walking, two lines, and three balances.” The clinical evaluation adopts the criteria of Qinsihe lower limb deformity correction and functional reconstruction.148 patients with post‐traumatic lower limb deformities were followed up for 40.9 (12–356) months. The main surgical procedures implemented were tendon lengthening and soft tissue release (84 cases), osteotomy (93 cases), joint fusion (30 cases), and tendon transposition (16 cases); there were multiple surgical procedures in some patients. Among them, 124 cases used external fixators for stress control and 27 cases used internal fixation, while 3 cases used plaster or brace. There were 5 wire reactions postoperatively, which improved after dressing change and oral antibiotics. There were 2 pin infections, which improved by pin removing. No surgical related deep infections occurred, and no surgical related neurovascular damage occurred. At the last follow‐up, all limb deformities were corrected, limb function improved, and the results of treatment was very satisfactory. According to Qinsihe evaluation criteria for lower limb deformities, 74 cases were excellent, 56 cases good, and 18 cases fair, with an excellent and good rate of 87.84%.Stress control with external fixation is effective, safe, and controllable in correcting and reconstructing post‐traumatic lower limb deformities. The principle of “one walking, two lines, and three balances” plays an important role in the entire process of stress control limb reconstruction. [ABSTRACT FROM AUTHOR]

Background: Traditional plaster‐cast fabrication of an ankle‐foot orthosis (AFO), although robust, is time‐consuming and cumbersome. 3D scanning is quickly gaining attention as an alternative to plaster casting the foot and ankle region for AFO fabrication. The aim of this study was to assess the accuracy and speed of two high‐performing 3D scanners compared with plaster casting in pediatric patients requiring an AFO. Methods: Ten participants (mean age 10.0 ± 3.9 years) prescribed AFOs for a movement disorder were 3D scanned with the high‐cost Artec Eva (Eva) and low‐cost Structure Sensor II (SSII) using one‐person (1p) and two‐person (2p) protocols. Accuracy and speed for both 3D scanners were compared with corresponding plaster cast measures (≤5% acceptable difference). Bland and Altman plots were generated to show mean bias and limits of agreement. Results: Overall, Eva and SSII were accurate for foot, ankle, and lower leg key clinical landmarks (Eva‐1p: 4.4 ± 7.3%; Eva‐2p: 3.2 ± 7.5%; SSII‐1p: 0.6 ± 7.4%; SSII‐2p: 0.7 ± 8.2%). Bland and Altman plots for the SSII demonstrated lower biases for 1p (bias 0.5 mm, LoA: −12.4–13.5 mm) and 2p (0.4 mm, LoA: −11.4–12.2 mm) protocols compared with Eva for 1p (bias 2.3 mm, LoA: −8.0–12.7 mm) and 2p (1.8 mm, LoA: −10.7–14.3 mm) protocols. The SSII 2p protocol was the fastest 3D scanning method (26.4 ± 11.1 s). Conclusions: The high‐cost Eva and low‐cost SSII 3D scanners using the 1p and 2p protocols produced comparable accuracy and faster capture of key clinical landmarks compared with plaster cast measures for the fabrication of AFOs in pediatric patients. [ABSTRACT FROM AUTHOR]

The calcareous materials used in constructing the Phaya Thon Zu temple at the Bagan historical sites in Myanmar are mortars, plasters, and stuccos. Among them, the mortars and plasters are a mixture of original and new materials used for recent conservation treatments. In this study, the making techniques were examined through analysis of calcareous materials by production period. All calcareous materials have a mineral composition similar to soil, except calcite. Stuccos have the most refined aggregates, homogeneous particle size, and the highest lime and organic contents. They were designed to improve ease of carving and weathering resistance, considering the unique characteristics of the stuccos. Because all calcareous materials were mixed with soil, the origin of the clay materials was analyzed. It was concluded that the mortars were produced by mixing clay and sandy soil, and the original mortars showed characteristics similar to soil. It is highly possible that sandy soil from around the Htillominlo temple was used to produce new plasters, and it is estimated that a mixture of clay soil was used for the original plasters and stuccos. A clear provenance interpretation of the original and raw materials used for each construction and the mixing ratio of clay materials need to be discussed through experiments, along with the estimated provenance area of the raw calcareous materials. [ABSTRACT FROM AUTHOR]

Nowadays, materials with a limited impact on the environment are required in the construction sector. Considering the interesting properties of natural elements such as natural fibers, it seems advantageous to use them to reinforce materials while protecting the environment and guaranteeing economic gain. Along these lines, this research was devoted to studying the effect of untreated natural fibers extracted from the Juncus maritimus plant (from Southern Morocco) on plaster. First, the effect of the percentage of added fibers on the fluidity of the plaster was evaluated by means of the Marsh's cone method, that is, by measuring the time taken by a known volume of plaster to flow from a cone through a short tube. Then, the highly porous microstructure of the plaster was observed using a scanning electron microscope (SEM). The diffractogram of Juncus maritimus fibers was built by means of a X-ray diffraction (XRD) method. The values obtained for the wet thermal conductivity of the composites decreased from 0.4853 W/m.K for the reference specimen to 0.4324 W/m K for a fiber volume content of 40%. The densities were calculated to determine the lightness of each composite. The mechanical strengths [flexural and compressive] were evaluated for different percentages of rush fibers. The addition of 20% volume fiber was found to improve the flexural strength to 3.63 MPa compared to the sample without fiber (3.36 MPa), thereby ensuring good toughness of the considered material. Nevertheless, a reduction in compressive strength was observed, due to the poor adhesion between the fibers and the plaster matrix. [ABSTRACT FROM AUTHOR]

Recent seismic events have prompted research into innovative and sustainable materials for strengthening and repairing obsolete and vulnerable buildings. These earthquakes have exposed the high seismic vulnerability of existing reinforced concrete (RC) buildings, particularly in secondary structural elements like infill walls. In addition to structural issues, these buildings often face significant energy deficiencies, such as thermal bridges, due to inadequate insulation. Traditionally, structural and energy improvements for residential buildings are addressed separately with different methods and protocols. This preliminary study is part of a broader research initiative at the University of Reggio Calabria (Italy), aiming to design an innovative fiber-reinforced plaster using natural, sustainable, and locally produced materials to enhance the energy and structural performance of existing wall infills. The study investigates two plaster matrices made of natural hydraulic lime and silica sand, with 15% and 30% cork granules added. Mechanical and thermophysical tests on multiple specimens were conducted to evaluate their suitability for seismic and energy retrofitting of infill walls. Results indicate that adding cork reduces mechanical strength by approximately 42% at a 30% cork content without compromising its use in seismic retrofitting. Thermophysical tests show improved thermal performance with a higher cork content. These findings suggest that the lime–cork mixture at 30% is effective, offering excellent ductility and serving as a promising alternative to traditional cementitious plaster systems. The next experimental phase will test matrices with varying percentages of gorse fiber. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For thousands of years, mortar-based materials — including bedding mortars, plaster floors, internal wall plasters, external wall renders and stuccos, and concrete — have been key construction materials in many cultures throughout the world. This paper gives an overview and examples of the use and development of mortar-based materials in cultures across the Middle East, Europe, Asia, and Mesoamerica, prior to the development of hydraulic cements in the late 18th and early 19th centuries. [ABSTRACT FROM AUTHOR]

In the realm of sustainable construction materials, the quest for low-environmental-impact binders has gained momentum. Addressing the global demand for concrete, several alternatives have been proposed to mitigate the carbon footprint associated with traditional Portland cement production. Despite technological advancements, property inconsistencies and cost considerations, the wholesale replacement of Portland cement remains a challenge. This study investigates the feasibility of using alkali-activated slag (AAS)-based binders for two specific applications: structural plaster and pervious concrete. The research aims to develop an M10-grade AAS plaster with a 28-day compressive strength of at least 10 MPa for the retrofitting of masonry buildings. The plaster achieved suitable levels of workability and applicability by trowel as well as a 28-day compressive strength of 10.8 MPa, and the level shrinkage was reduced by up to 45% through the inclusion of shrinkage-reducing admixtures. Additionally, this study explores the use of tunnel muck as a recycled aggregate in AAS pervious concrete, achieving a compressive strength up to 20 MPa and a permeability rate from 500 to 3000 mm/min. The relationship between aggregate size and the physical and mechanical properties of no-fines concretes usually used for cement-based pervious concrete was also confirmed. Furthermore, the environmental impacts of these materials, including their global warming potential (GWP) and gross energy requirement (GER), are compared to those of conventional mortars and concretes. The findings highlight that AAS materials reduce the GWP from 50 to 75% and the GER by about 10–30% compared to their traditional counterparts. [ABSTRACT FROM AUTHOR]

In this study, mortar and plaster samples taken from a traditional house (1799 parcel) located in the neighborhood Konuralp, Düzce Province, were subjected to acid loss, ignition loss, loss of aggregates sieve analysis after acid, protein, and fat tests, tests of salt, as well as Petrographic and SEM-EDX analyses. Brick samples underwent physical examinations microscopic analyses and mechanical in addition to SEM-EDX analyses. For wood samples, macroscopic and microscopic analyses were conducted to determine their types. Based on these analyses, recommendations have been made to contribute to the repair and reuse of the material properties of the selection processes of traditional structures. [ABSTRACT FROM AUTHOR]

Jet fires are the second most common fire scenario after spill fires. This type of fire is characteristic of gas and gas–oil fires occurring on oil platforms and gas production and processing plants. The consequences of such fires are characterized by high material damage; this is associated with extensive networks of technological communications, since there is a high density of technological facilities and installations in the territory where these fires occur. At such facilities, there is a large number of steel structures, which under the action of high temperature quickly lose their strength and deform. To protect steel structures in the oil and gas industry, fire protection is used, which consists of different types: boards in the form of flat plates, plasters, and epoxy paints. This paper compares three types of fire protection materials for steel structures under jet fire: board fireproofing, plaster composition, and epoxy coating. When comparing the efficiency in jet fire, cement boards were found to be the best. However, despite the better fire protection efficiency, their low application is expected due to their massiveness and the high cost of such protection and the difficulty of installation. Nevertheless, the development of fire depends on the place of its origin, the size of the initial fire zone, and the stability and massiveness of the metal elements of the vessel structure or the structure of the boards on which the equipment can be placed. Therefore, it is necessary to take these factors into account when selecting fire protection and to apply it depending on the required fire resistance limits of structures, which should be determined depending on the fire development scenarios. [ABSTRACT FROM AUTHOR]

The Dunhuang murals, a significant part of Chinese heritage, have suffered deterioration primarily due to environmental and chemical factors, notably salt damage. This study proposes a sophisticated method that synergizes Fractional Order Differentiation (FOD) and Partial Least Squares Regression (PLSR) to accurately invert the phosphate content in the mural plaster of the Dunhuang paintings. The focal points of the research include: (1) To address the issue of information loss and reduced modeling precision caused by integer-order differentiation algorithms, the FOD method is employed for preprocessing spectral data. This approach ensures the fine spectral differences in the phosphate content of the mural plaster are precisely captured, (2) Utilizing PLSR, the study models the spectral bands identified at a significance level of 0.01 with measured conductivity values, thereby enabling the precise prediction of the phosphate content in the murals. The research outcomes reveal: (1) The FOD method can elucidate the nonlinear characteristics and variation patterns of the mural samples in the spectral data. As the order increases from zero to two, the number of spectral bands meeting the 0.01 significance test initially decreases and then increases. The highest absolute value of the positive correlation coefficient is observed at the 1.9 order, corresponding to the 2077 nm band, (2) For predicting the phosphate content in the murals, the model at the 1.9 order is most suitable for inversion. This model, after cross-validation, achieves a maximum R2 value of 0.861. This study created an efficient FOD-based model for estimating phosphate in mural plaster. [ABSTRACT FROM AUTHOR]

Regulating the crystal morphology of low aspect ratio, short columnar α‐hemihydrate gypsum (α‐HH) is crucial due to its distinctive physical and chemical properties, which make it widely applicable. In this work, succinic acid, malic acid, and maleic acid were selected as the research objects, among which the number and spacing of carboxyl groups were the same, while the auxiliary functional groups were different. The adsorption energy, Mulliken charge population, electronic state density, and charge density difference of the three organic acids on the surfaces of α‐HH were calculated by well‐defined ab initio calculations. The results showed that the synergistic effect of ‐COOH groups is necessary for the effective crystallization of α‐HH. Organic acids interact with the Ca atoms on the crystal surface, as evidenced by their preferential adsorption on the top surface of α‐HH crystals (002). This interaction occurs through a double‐dentate chelation between the carboxyl oxygen atoms at both ends of the organic acid and the Ca atoms on the crystal surface, resulting in the formation of a six‐membered cyclic organic acid calcium complex. This complex hinders ion diffusion and the stacking of crystal surfaces, leading to a decrease in the growth rate along the c‐axis and promoting more extensive crystal development and larger crystal sizes. The work provides insight into the preparation of short prismatic α‐HH using organic acid crystallizing agents. [ABSTRACT FROM AUTHOR]

Silica aerogel has remarkable properties, particularly its translucence/transparency, extremely low thermal conductivity and density. Due to these properties, it can be used for the thermal insulation of buildings for energy saving, cost saving, and enhanced comfort. In this context, aerogel products such as aerogel blankets have already started to demonstrate their effectiveness in retrofitting projects and the development and adoption of aerogel glazing systems and aerogel-enhanced renders is promising. Other products, for example, through the incorporation of silica aerogel granules in cement and lime renders were obtained, with high thermal insulation properties, to achieve energy efficiency on buildings facades. This research aims to come up with new aerogel particle composition insulation plasters at cost-effective rates for application in building insulation. Their physical apparent mass density, mechanical–flexural and compressive strengths, thermal conductivity, and properties were investigated. As an experimental study, the thermal conductivities of six sets of cement and lime plasters with aerogel particles (0.1–4.0 mm) were investigated and it was concluded that the thermal conductivity of cement and lime plasters with 80% aerogel was 0.2287 W·m−1·K−1, about 3.4 times smaller than the respective value of traditional lightweight plasters of 0.76 W·m−1·K−1, while the cement and lime plasters with less than 40% aerogel showed a thermal conductivity value as low as 0.3172 W·m−1·K−1. It was confirmed that the end product plasters' mechanical qualities included low apparent mass densities, no apparent shrinkage, and mechanical strength values that matched those of the prepared compositions. This suggests that the obtained plasters are suitable for use in both new constructions and renovation projects. [ABSTRACT FROM AUTHOR]

The optimal scan pattern for full-arch digital implant impressions remains to be determined. This study aimed to analyze the effects of different scan patterns on the trueness of intraoral scanners for full-arch digital implant impressions. A maxillary plaster model with 4 implant analogs was employed as the master model. Scan bodies were attached to the master model and scanned with a laboratory scanner to obtain reference data. Test scans were obtained using 3 different scan patterns with Cerec Primescan and Trios 3. Each test datum was superimposed onto the reference data. The trueness was assessed by determining the 3D distance and angular deviations between the test and reference data. Significant differences in 3D distance deviation were detected among the scan patterns for both scanners. Significant differences in angle deviation were detected among the scan patterns for the Cerec Primescan, whereas it was not substantial for the Trios 3. Cerec Primescan exhibited superior trueness across all scan patterns compared with Trios 3. The zigzag pattern resulted in more accurate scans for the Cerec Primescan, whereas both the zigzag and occlusal-palatal-buccal patterns showed higher accuracy for the Trios 3. [ABSTRACT FROM AUTHOR]

The construction industry has been constantly expanding and is, consequently responsible for a high consumption volume of natural raw materials and for generating large amounts of waste. In detriment of this scenario, this research proposes the reuse of Construction and Demolition Waste (CDW), especially that from plaster for making mortars. The residue was thermo-activated at 650 °C for a period of 2h, a heating rate of 10 °C/min, it was crushed in a jaw crusher and passed through an ABNT N° 16 sieve. The mortars were prepared with a (cement:sand) ratio of 1:6 by mass, the sand was partially replaced by the residue in proportions of 0, 10, 20 and 30%, using Ordinary Portland Cement (OPC). Tests were carried out on consistency index, mass density, incorporated air content, isothermal calorimetry, water retention, mass density in the hardened state, flexural strength, compressive strength, water absorption and void index, in addition to testing techniques characterization, such as laser granulometry, pozzolanic activity using the Modified Chapelle method and Lúxan method, X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) as well as Mercury Intrusion Porosimetry (MIP). It was possible to observe that the residue has amorphous phases, through XRD and heterogeneous nucleation of smaller particles, proven by the calorimetry test, contributing to the increase in mechanical strength. The results indicate that the mixture with 30% replacement achieved a greater increase in mechanical strength, lower absorption rates and consequently, a reduction in the distribution of pore sizes.

Introduction. The study was carried out to determine the possible causes of damage to the finishing plaster coverings on the facades of historical stone buildings, built in St. Petersburg before 1917, as a result of their humidification and subsequent frost destruction.Materials and methods. The mechanism of humidification of a homogeneous wall structure plastered on both sides due to the moisture transfer from the room to the environment through the wall thickness due to the difference in partial pressures of water vapour from inside and outside the room during the cold season is studied. The paper provides the graphs of the distribution of the actual and maximum partial pressures of water vapour over the thickness of the wall structure, depending on the type of plaster covering, for two calculated cases — for the conditions of the coldest month and the coldest five-day period in St. Petersburg.Results. It is revealed that for the conditions of the coldest month in St. Petersburg, the actual partial pressure of water vapour in the thickness of the wall structure under consideration does not exceed the maximum, which indicates the absence of conditions for moisture condensation in the thickness of the wall envelope. However, as the vapour permeability of the external plaster decreases, the curves of the distribution of the actual and maximum partial pressures converge at the interface of the stone base and the plaster covering. For the conditions of the coldest five-day period, the actual partial pressure of water vapour already at a distance of 135 mm from the inner surface exceeds the maximum partial pressure, which indicates a high risk of moisture condensation, and this risk is the higher the less vapour permeable the plaster covering is.Conclusions. It is proven that when the coldest outdoor temperatures are established, there is a high probability of condensation of water vapour in the thickness of the wall structure under consideration. The highest risk of freezing of the condensable moisture will be observed at the interface of stone base with the external plaster. Freezing of moisture in cracks and voids in the contact zone of the stone base and the plaster covering can lead to water trapping, the occurrence of significant internal stresses in the finishing layer and, as a result, to its gradual damage, up to the loss of individual fragments of plaster.

Abstract A diagnostic investigation was carried out on twelfth century Byzantine wall paintings preserved in the Museum of Byzantine and Norman Culture and Figurative Arts of San Marco d’Alunzio (Messina, Italy) on the occasion of recent restoration works. First, the wall paintings were analyzed using portable X-Ray Fluorescence (p-XRF) and Fiber Optics Reflectance Spectroscopy (FORS) to obtain a non-invasive preliminary identification of the original palette. Then, five fragments were sampled for a micro-stratigraphy study using Digital Optical Microscope (DOM), Polarizing Optical Microscope (POM), and Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray Spectrometry (EDS) to characterize the mortars and the blue and black pigments non unequivocally identified through non-invasive techniques. The palette included mainly earthen pigments like red and yellow ochres, green earth, and more valuable lapis lazuli blue applied on a bone black layer; while the analysis of mortars found on the different apses showed the same manufacturing technique and constitutive materials: lime-based binder with the addition of quartz, and rare calcareous lithic fragments as aggregate. The obtained results shed light on the pictorial technique used for the wall paintings and allowed us to compare the Sicilian pictorial cycle with the coeval Byzantine wall paintings preserved in Sardinia and Southern Italy.

Even in digital workflows, models are required for fitting during the fabrication of dental prostheses. This study examined the influence of different parameters on the dimensional accuracy of three-dimensionally printed models. A stereolithographic data record was generated from a master model (SOLL). With digital light processing (DLP) and stereolithography (SLA) printing systems, 126 models were produced in several printing runs—SolFlex350 (S) (DLP, n = 24), CaraPrint 4.0 (C) (DLP, n = 48) and Form2 (F) (SLA, n = 54)—and their accuracy was compared with plaster and milled polyurethane models. In addition to the positioning on the build platform, a distinction was made between parallel and across arrangement of the models to the printer's front, solid and hollow models, and printing with and without support structures. For accuracy assessment, five measurement sections were defined on the model (A–E) and measured using a calibrated digital calliper and digital scans in combination with the GOM Inspect Professional software 2021. The mean deviation between the measurement methods for all distances was 79 µm. The mean deviation of the models from the digital SOLL model were 207.1 µm for the S series, 25.1 µm for the C series and 141.8 µm for the F series. While positioning did not have an influence, there were clinically relevant differences mainly regarding the choice of printer, but also individually in alignment, model structure and support structures. [ABSTRACT FROM AUTHOR]

This article presents a case of complex investigation of defects of lime mortar and plaster that have been developing over a period of 48 years in a house in Prague and are strongly influenced by thermal and salt crystallization cycles. The aim of this research was to describe the degradation phenomena of mortars and plasters observed on a narrowly limited part of the building, combining structural elements of different types and ages and to explain the mechanisms of their formation and development. The geometric characteristics of the defects were determined by non-destructive methods, especially optical interference moiré, laser profilometry, photogrammetry, and infrared thermography. Material data were determined on samples by electron microscopy, ion exchange chromatography, and direct moisture content measurements. The results supported the hypothesis of the increase in the deformation of large buckles of detached plasters by the mechanism of buckling caused by loading of the edges with compression generated by volume changes. Direct loading of the boundary surfaces causes the formation of bulges in the confined areas. This study shows the importance of failure analysis of real structures to gain knowledge about the behavior of structures and materials under long-term service conditions. [ABSTRACT FROM AUTHOR]

The 1D moisture diffusivity of porous materials may strongly depend on the content of moisture in the materials, varying over an order of magnitude or more. In this paper we present a new model from which the diffusivity can be evaluated, using the pore size distribution and water absorption coefficient. We point out that this is a more efficient approach than the standard Boltzmann–Matano (BM) method, because measurements of pore curves and water absorption are much shorter and rather accurate compared to moisture profile experiments needed in the BM method. As an example, we apply our model to two samples of a ceramic brick for which experimental data on both pore curves and moisture profiles had been measured. A very good quantitative agreement in the diffusivity is obtained for early stage profiles. For later stages, however, the model predicts three to four times higher diffusivity than the BM method. The reasons for this discrepancy are discussed and further tasks to validate the effectiveness of the new model are proposed. We also compare our model with the pore models of Burdine and Mualem. [ABSTRACT FROM AUTHOR]

This study focuses on the Memorial Chapel, a historical site located inside the Tempio Evangelico Valdese in Florence. In 1843, the first Anglican church in Florence, known as Holy Trinity Church, was built by D. Giraldi. Around 1892, G. F. Bodley began the reconstruction of a new building of neo-Gothic style at the same site, which was completed in 1904. This new church had a space dedicated to memory called Memorial Chapel. In 1967, the monumental complex was acquired by the Waldensians, now known as the Tempio Evangelico Valdese. This interdisciplinary investigation aimed to study the most damaged painted walls of the chapel. For this purpose, samples of decorative plaster mortars were collected from various points, after carrying out a digital mapping of the degraded areas. Mineralogical, petrographic, optical, chemical, and microchemical analyses were performed. This study made it possible to highlight the composition and the characteristics of the different layers of the plaster mortars, permitting us also to identify the types of pigments used over time in the paintings; furthermore, it was possible to reconstruct the degradation phenomena on the walls and the events that caused them, providing valuable insight for targeted restoration efforts. [ABSTRACT FROM AUTHOR]

William J. Woodhouse was honorary curator of the Nicholson Museum, University of Sydney, from 1904 until 1937. During his curatorship he undertook a significant acquisition of plaster casts to enhance the representation of Greek and Italian sculpture alongside the existing ceramics collection. At its height the collection included well over 250 plaster casts and reproductions. Today the majority of the cast collection has been deaccessioned and, instead, his personal collections of ceramic sherds and photography, donated after her father's death by his daughter Liska Woodhouse, have become Woodhouse's curatorial legacy. This paper introduces Woodhouse's role as curator, and examines each of his unique collections to analyse how Woodhouse himself conceived of his legacy and the reality represented in the Nicholson collection today. Central to this paper is an exploration of how collecting priorities and the perception of authenticity and narrative value changed in museums of antiquities during the twentieth century. [ABSTRACT FROM AUTHOR]

The medieval and early modern stone collection of the National Museum of the History of Transylvania originated as an integral part of the Coin and Antiquities Collection of the museum’s predecessor, the Transylvanian Museum Society. Over time, it has developed into one of the richest collections in the Carpathian Basin, now comprising approximately 600 carvings. The study is divided into two major chapters. The first chapter covers the history of the collection, while the second provides a detailed description of it. The first chapter traces the history of the stone collection from the founding of the Transylvanian Museum Society, the predecessor of the current museum, to the most recent reorganization of the stone collection. The second chapter of the study presents the medieval and early modern stone collection, showcasing the exhibited pieces through three main thematic groups: tombstones, architectural carvings, and plaster casts. [ABSTRACT FROM AUTHOR]

In the solidification of plasters, promptly identifying layering defects is vital to reduce later inspection and maintenance expenses. Traditional tapping methods for defect detection, while widespread, are inefficient and can damage walls. This study proposes an innovative method utilizing Infrared Thermal Imaging (IRT) for semi real-time detection of layering defects during the solidification phase. The method was applied within the first 48 h following the application of two different plasters (Cement and Gypsum, mixed on-site as needed, not pre-dosed, and applied in a single layer), systematically examining the effects of plaster composition and environmental temperature conditions. The results showed that all preset defects were successfully identified. It was observed that larger defects are more readily detectable at a given thickness, and conversely, thicker defects are more discernible at a fixed size, with the dimension of the defect having a more pronounced impact on absolute contrast than its thickness. Notably, cement plaster exhibited two distinct temporal windows for defect detection, primarily influenced by environmental temperatures. In contrast, gypsum mortar presented two detection phases, with the initial phase being predominantly governed by the heat of hydration and the latter by ambient temperature conditions. The application of IRT technology in this research demonstrates its efficacy in accurately detecting layering defects during the solidification of plasters. This method offers valuable insights and guidance for the application of plaster layers in real-world engineering scenarios, potentially reducing maintenance costs and improving construction quality. [ABSTRACT FROM AUTHOR]

A diagnostic investigation was carried out on twelfth century Byzantine wall paintings preserved in the Museum of Byzantine and Norman Culture and Figurative Arts of San Marco d'Alunzio (Messina, Italy) on the occasion of recent restoration works. First, the wall paintings were analyzed using portable X-Ray Fluorescence (p-XRF) and Fiber Optics Reflectance Spectroscopy (FORS) to obtain a non-invasive preliminary identification of the original palette. Then, five fragments were sampled for a micro-stratigraphy study using Digital Optical Microscope (DOM), Polarizing Optical Microscope (POM), and Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray Spectrometry (EDS) to characterize the mortars and the blue and black pigments non unequivocally identified through non-invasive techniques. The palette included mainly earthen pigments like red and yellow ochres, green earth, and more valuable lapis lazuli blue applied on a bone black layer; while the analysis of mortars found on the different apses showed the same manufacturing technique and constitutive materials: lime-based binder with the addition of quartz, and rare calcareous lithic fragments as aggregate. The obtained results shed light on the pictorial technique used for the wall paintings and allowed us to compare the Sicilian pictorial cycle with the coeval Byzantine wall paintings preserved in Sardinia and Southern Italy. [ABSTRACT FROM AUTHOR]

Objectives: Describing mitochondrial oxygenation (mitoPO2) and its within- and between-subject variability over time after 5-aminolevulinic acid (ALA) plaster application in healthy volunteers. Design: Prospective cohort study. Setting: Measurements were performed in Leiden University Medical Center, the Netherlands. Participants: Healthy volunteers enrolled from July to September 2020. Interventions: Two ALA plasters were placed parasternal left and right, with a 3-hour time interval, to examine the influence of the calendar time on the value of mitoPO2. We measured mitoPO2 at 4, 5, 7, 10, 28, and 31 hours after ALA plaster 1 application, and at 4, 5, 7, 25, and 28 hours after ALA plaster 2 application. Primary and secondary outcome measures: At each time point, five mitoPO2 measurements were performed. Within-subject variability was defined as the standard deviation (SD) of the mean of five measurements per timepoint of a study participant. The between-subject variability was the SD of the mean mitoPO2 value of the study population per timepoint. Results: In 16 completed inclusions, median mitoPO2 values and within-subject variability were relatively similar over time at all time points for both plasters. An increase in overall between-subject variability was seen after 25 hours ALA plaster time (19.6 mm Hg vs 23.9 mm Hg after respectively 10 and 25 hours ALA plaster time). Conclusions: The mitoPO2 values and within-subject variability remained relatively stable over time in healthy volunteers. An increase in between-subject variability was seen after 25 hours ALA plaster time warranting replacement of the ALA plaster one day after its application. Trial registration: ClinicalTrials.gov with trial number NCT04626661. [ABSTRACT FROM AUTHOR]

Objective: To determine the frequency of functional outcome after conservative treatment in patients with distal radius fractures presenting to Hayatabad Medical Complex, Peshawar. Study Design: Descriptive Case Series. Setting: Department of Orthopedics, Hayatabad Medical Complex, Peshawar. Period: 1st January 2022 to 30th June 2022. Methods: A total of 137 patients of both gender with distal radius fracture were included in the study. A Basic demographics (age, gender, duration of fracture and weight on weighing scale) were recorded. At the end of 6 weeks, the plaster cast was removed and functional outcome examinations was made. Functional outcome was noted using demerit point system of Gartland and Werley. Results: Age range in this study was from 18 to 70 years with mean age of 44.153±8.19 years, mean duration of complain 26.708±4.18 hours and mean weight was 80.343±7.05 Kg. Male patients were 70.8% and females were 29.2%. Excellent functional outcome was seen in 33.6% patients, good 14.6%, fair 34.3% and poor was 17.5%. Conclusion: Our study concluded that conservative management of the distal radius fractures in plaster cast is an effective treatment modality achieving satisfactory results. [ABSTRACT FROM AUTHOR]

Parts of a subterranean hiding complex and a miqveh (ritual bath) were excavated at Ḥorvat Maskana in 2020. The Byzantine pottery from the excavation, along with the dating of the plaster, suggests that the complex was used in the Byzantine period and may originally have been hewn in the Roman period. Additional hiding complexes with not only Roman but also Byzantine pottery exist elsewhere in Galilee. The presence of Byzantine pottery inside some of the hiding complexes points to the possibility that their use should not be limited to the Roman period, and that there may have been limited use in the Byzantine period by the local Jewish Galilean. [ABSTRACT FROM AUTHOR]

Elephant grass (Pennisetum purpureum) exhibits high biomass production, is readily accepted by animals, and demonstrates good adaptation to the various soil types. Consequently, the utilization of P. purpureum shows promise in amending surface and subsurface soil acidity, thereby contributing to increased crop yield while enhancing water and nutrient utilization efficiency. In this study, the effects of corrective processes involving limestone and plastering on the root anatomy of P. purpureum were investigated. Roots subjected to different treatments were fixed, dehydrated, and embedded in historesin. Subsequently, samples were sectioned in a microtome, stained with toluidine blue for the conventional analysis, or submitted to the histochemical test. The qualitative and quantitative anatomical analyses were conducted to evaluate the impact of liming and plastering on the root structure of P. purpureum. The results showed that liming led to an increase in both the number and diameter of vessel elements, while plastering reduced these parameters compared to the acidic soils. Additionally, liming induced the formation of suberized endodermal cell walls. These findings highlight the significance of effective soil management to obtain P. purpureum plants with a well-developed vascular system, thereby promoting optimal plant performance in agricultural crops. [ABSTRACT FROM AUTHOR]

Facade-rendering mortars and their painting layers are constantly exposed to weather and, therefore, influence the hygrothermal behavior of buildings. The characterization and assessment of coating materials is fundamental, seeking adequacy in their selection, especially regarding moisture and temperature. Considering the exposure conditions of the facades, risks of damages, such as mold development, may be avoided by an assertive evaluation and selection among different types of paints. In this context, this paper experimentally determined essential properties related to the hygrothermal behavior of painted mortars and simulated their resulting performance when applied on exposed facades in three Brazilian cities in distinct bioclimatic zones. Hygrothermal simulations were carried out using the software WUFI Pro 6.6. Six different types of paints were studied, among which satin acrylic paint (SAP) led to the lowest water vapor permeability and matte polyvinyl acetate (PVA), silicate (SIL), lime (LP), and hydrated lime with white glue (HLG) paints led to the highest. Matte acrylic paint (MAP), PVA, SIL, LP, and HLG had similar impacts on the vapor transmission of mortar renderings. In the simulations, reference (REF) and LP specimens generally resulted in the highest water contents throughout the year, followed by SIL and HLG. SAP led to the lowest water content and a more homogeneous curve than the other paints. Among the studied cities, Macapá, which has the highest annual normal rainfall sum and mean relative humidity, also had the highest mean total water content values over time, followed by Porto Alegre and Petrolina. In general, no probable mold development is expected. However, caution should be taken when extrapolating the results for climate or construction conditions different than the simulated ones. [ABSTRACT FROM AUTHOR]

Capillary water absorption is an important parameter to evaluate the durability of cement mortars. For testing the capillary water absorption of cement mortars, drying is a necessary and crucial procedure. However, different standards have different requests on drying temperatures for doing the tests. Since the calcium aluminate cement-hemihydrate gypsum (CAC-C S ¯ H0.5) mortars are temperature-sensitive, three temperatures of 20 °C, 40 °C and 70 °C were selected to study the effect of hydroxypropyl methyl cellulose (HPMC) on the capillary water absorption of these mortars. The influence of temperature on the capillary water absorption of the mortars was analyzed from the perspectives of pore structure and hydration. The results show that when the viscosity of HPMC is the same, the higher the dosage of HPMC used, the higher the capillary water absorption of mortars. When the dosage of HPMC is the same, the higher the viscosity of HPMC, the greater the capillary water absorption of mortars. The addition of HPMC can significantly increase the total porosity of mortars, especially the volume of the large pores. However, pore structure is not the main factor influencing the capillary water absorption of HPMC-modified CAC-C S ¯ H0.5 mortar. When the drying temperature rises to 40 °C, a small amount of AFt is decomposed. When the drying temperature reaches 70 °C, most of AFt is carbonized to form hemicarboaluminate and AH3, and the latter is the key to refining the pore structure of mortars. The temperature change causes a phase transition of the hydration products, thereby altering the pore structure. 40 °C is suggested as an appropriate drying temperature for the capillary water absorption test of the investigated mortars. [ABSTRACT FROM AUTHOR]

The study of organic stabilization is crucial for understanding its impact on the durability and effectiveness of earthen plaster. Analyzing natural admixtures' effects on plaster properties provides insights that aid in optimizing plaster composition and application for desired characteristics. The addition of biopolymers, known to enhance plaster performance, necessitates further investigation to understand their role in earthen plaster stabilization. This study focuses on Tata Somba homes in Benin and Togo, recognized as UNESCO World Heritage sites. These unique architectural examples embody "architecture without architects", relying solely on local traditional knowledge. The objective is to explore and revive Tata Somba's ancient eco-technology for earth plaster stabilization. Research shows that biopolymers' combined stabilization and application techniques can improve earthen plaster performance. Seven promising bio-stabilizers were identified, suggesting their potential as sustainable, effective options for CO 2 mitigation in buildings. These findings not only deepen our understanding of earthen architecture but also underscore the potential of merging traditional, eco-friendly building methods with modern scientific insights to create sustainable solutions for cultural heritage preservation and contemporary built environments. [ABSTRACT FROM AUTHOR]

Geochemically driven alterations of fractures in multi‐mineral media can create altered layers (ALs) at the fracture‐matrix interface. Spatial variations in the AL significantly influence mass transfer across the interface, and the hydraulic and mechanical properties of the fractured medium. A real‐rock based microfluidic experiment reported spatial variations in AL thickness despite the initially smooth fracture surface, suggesting potential effects of matrix heterogeneity on AL development. However, the respective contribution of structural and mineralogical characteristics is still poorly understood. Using the microfluidic experimental data and a micro‐continuum reactive transport model, we systematically evaluated how micro‐porosity and initial mineral texture impact AL development and thus the overall reactive transport behaviors. Our simulation results confirmed that the extent of AL spatial variations, mainly controlled by mineralogical texture, influences the evolution of reaction and permeability in different ways. Accounting for spatial heterogeneity in mineral distribution produces "channeling" structures in ALs and lower overall reaction (by up to 35.6%), but larger permeability increase (by up to 9.8%). The characteristic length of the reactive mineral cluster was observed to dominate the internal texture of ALs. Whereas the presence of micro‐porosity can enhance mineral accessibility via improving connectivity for flow and transport, and lead to both higher bulk reaction, that is, thicker ALs, and permeability enhancement. Considerations of surface roughness with characteristic length on the same order of magnitude as mineral texture did not change the overall development of AL, which further highlights the importance of accounting for rock matrix properties in predicting long‐term evolution of fractured media. The resulting spatial variations of ALs and their impacts on bulk properties, however, are expected to be further complicated by the coupling of chemical and mechanical processes, and may trigger matrix disaggregation, erosion and other mechanisms of fractured media alteration. Key Points: Spatial variations in altered layers affect the evolution of bulk reaction and permeability in fractured mediaThe characteristic length of reactive mineral clusters dominates the internal texture of the altered layer and permeability enhancementThe presence of micro‐porosity in the matrix promotes mineral accessibility, reactive transport, and thus thickening of altered layers [ABSTRACT FROM AUTHOR]

A central debate is the improvement in the mechanical and water resistance of sustainable earthen architecture without additives or stabilizers. This innovative work aims to test the effects of a graphene-based additive, optimized for the improvement in concrete properties, on the strength and water resistance of raw-earth plasters without any stabilizer other than sand. Given the heterogeneous nature of raw earth, three different soils were tested by adding three increasing graphene-based additive contents (0.01, 0.05 and 0.1 wt% of the earth–sand proportion). The link between soil intrinsic properties, i.e., geotechnical and mineralogical properties, and their interaction with the additive were investigated through geotechnical characterization, as well as mineralogical characterization, by XRD and ATR-FTIR analyses. The experimental tests carried out focused on the adhesion properties of the twelve different plasters on standard hollow bricks and on their interaction with water through capillary rise tests and erosion resistance tests. Conclusion from the experimental tests suggests that the graphene-based additive in earth plasters, by increasing the cohesion of the mixture, improves their adhesion performance. [ABSTRACT FROM AUTHOR]

This paper aims to valorize the excavated earth (ExE) generated from the tunnel digging works, to elaborate excavated earth-based plasters for masonry walls. Excavated earth is an admixture of water, gravel, sand, and fine particles. A small amount of gravel (<4% by weight) was removed, and the tunnel-excavated earth is used to elaborate plasters. Cement and slag are used as stabilizers in ExE-based plasters and reinforced with natural hemp fibers. The physical, mechanical, thermal, and hydric properties of ExE-based plasters are investigated. The increase in cement content affects the workability of ExE-based plasters in a fresh state, while the addition of natural hemp fibers has no significant effect on the workability. It has been demonstrated that the mechanical performances (compressive strength, flexural strength, and dynamic modulus) of ExE-based plasters increase with the increase of cement content and decrease with the increase in slag content. The hemp fiber addition (0.8% by weight) shows no considerable effect on the ExE-based plaster's mechanical performance. As for the thermal properties, the increase of cement and slag contents negatively affects the thermal conductivity. The increase in cement content decreases the water absorption of earth-plasters. Except for some tests (shrinkage, main cohesion, and cracking tests), which have not been done in this study, the results of cement-stabilized ExE-based plasters (7% and 9%) are in accordance with the recommendation of the DIN 18947 standard, indicating that the tunnel excavated earth can be used as earth-plasters. [ABSTRACT FROM AUTHOR]

• The processes and mechanisms of cracking and flaking damage in mural were studied. • A numerical method was used to investigate the moisture-induced cracking of mural. • The simulation result reproduced the process of surface shrinkage and cracking. • Nanoindentation test was used to measure the mechanical parameters of mural. Under various environmental conditions, including fluctuations in humidity, murals may undergo degradation processes, such as craquelures and flaking, reducing their cultural significance. This study employs the RFPA numerical simulation method, integrating humidity, stress, and damage factors to explore the response of the color layer of the Mogao Grottoes mural in China to moisture-induced cracking. To achieve this, a numerical model was constructed, encompassing both the color layer and the plaster layer. The simulation results accurately reproduce the surface shrinkage, cracking, and flaking. Findings indicate that the development of craquelures and flaking in the mural is linked to humidity gradient-induced shrinkage and material properties of the color layer and plaster layer. Moreover, factors like surface drying speed, color layer thickness, and binder content influence the cracking process. This research provides novel insights into the developmental processes and mechanisms underlying surface craquelures and flaking degradation in ancient cultural relics, such as murals. [ABSTRACT FROM AUTHOR]

The time-dependent interfacial adhesion between rock and fresh mortar is key for printing concrete linings in mountain tunnels. However, a scientific deficit exists in the time-dependent evolution of the interfacial adhesion, which can cause adhesion failure when printing tunnel lining. Nanoclay has the potential to increase the interfacial adhesion and eliminate the adhesion failure. Before the actual printing of tunnel linings, the time-dependent interfacial adhesion between artificial rock and fresh mortar modified by nanoclay should be understood. This paper studied the time-dependent interfacial adhesion based on fast tack tests, fast shear tests, and isothermal calorimetry tests. With the addition of nanoclay, the maximum tensile stress and the maximum shear stress increased. Compared with a reference series, the maximum interfacial tensile stress in a 0.3% nanoclay series increased by 106% (resting time 1 min) and increased by 209% (resting time 32 min). A two-stage evolution of the interfacial adhesion was found with the addition of nanoclay. In the first stage, the time-dependent interfacial adhesion increased rapidly. A 0.3% NC series showed an increase rate six times higher than that of the reference series. As the matrices aged, the increase rate slowed down and followed a linear pattern of increase, still higher than that of the reference series. The stiffening of fresh matrices resulted in the interface failure mode transition from a ductile failure to a brittle failure. The effect of nanoclay on flocculation and on accelerating the hydration contributed to the time-dependent interfacial adhesion between artificial rock and fresh mortar. [ABSTRACT FROM AUTHOR]

Concrete defects have a significant impact on concrete constructions. These defects should be considered not only aesthetic defects but also structural defects. In this study, a novel Surface Defect Index (SDI) method was developed to quantify the defect volume according to liquids' penetrating properties by applying ready-mixed plaster (RMP). The SDI refers to the volumetric proportion of all apparent and unapparent defects in a given area of concrete, and it is expressed as a percentage of the total volume affected by defects. The proposed SDI method was validated and tested under various controlled defect configurations. Regardless of the specific characteristics of each defect configuration, the SDI method consistently demonstrated a high level of consistency, repeatability, and reproducibility, with coefficients of variation (CVr and CVR) below 5% and with correlation coefficients of R2 = 0.9968. The method succeeded in assessing the surface quality levels through the SDI, demonstrating a significant correlation between this index and the volume of defects. The proposed index was tested on real concrete surfaces, affirming its efficacy in accurately quantifying the volume of surface defects; thus, it can provide an important metric for quality control. Moreover, it provides an excellent evaluation of the quality of concrete surfaces. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine potential deviation in measurements of commonly used orthodontic variables, including intermolar width (IMW), intercanine width (ICW), and arch perimeter (AP), when measured on three-dimensional images compared to measurements performed on plaster models obtained from alginate impressions using a hand-held digital vernier caliper. A total of 120 sets of models were divided into four groups: plaster models made from an alginate impression, digitized plaster models made from an alginate and silicone impression, and digital models obtained via intraoral scan. The repeated measurements analysis of variance (ANOVA) with Sidak post-hoc test was applied to test differences in measurements between the four methods. The results show better agreement for intermolar and intercanine width (r = 0.468–0.967) and smaller measurement error (ME = 0.53–1.07) compared to arch length (r = 0.422–0.477; ME = 2.04–2.89). Better agreement levels were more frequently observed between plaster models with intraoral scans than between digitized plaster models. The deviations in intermolar and intercanine width measurements between the hand-held digital vernier caliper and digital analyses were found to be clinically insignificant. The observed difference in arch perimeter suggests that curved measurements may not be clinically acceptable. [ABSTRACT FROM AUTHOR]

Background Acute fracture of a left main (LM) stent during angioplasty is a rare complication. Cardiologists should be aware of the risk of stent fracture (SF) following kissing balloon inflation (KBI) even if the effective diameter of the balloons does not exceed the recommended expansion limits of stents. Case summary A 64-year-old female with hypertension and dyslipidaemia presented with crescendo angina since three months in spite of optimal medical therapy. Coronary angiogram showed a distal LM bifurcation lesion. The patient was admitted for LM bifurcation stenting by upfront two-stent technique (inverted double-kissing Culotte technique). Following first KBI of the stent placed from left circumflex artery (LCX) to LM, there was stent deformation in the LM shaft. As we had planned the Culotte technique, we decided to exclude the fractured segment by stenting from left anterior descending artery (LAD) to LM. The stent from LAD–LM successfully excluded the fractured part of the first stent from the lumen of LM. Optical coherence tomography done after final KBI from LCX–LM revealed successful exclusion of the deformed segment of the LCX stent with mild malapposition at the site of the deformed stent. A follow-up angiogram after six months showed normal in-stent flow with no evidence of restenosis or pseudoaneurysm. Discussion Acute LM SF during coronary intervention can occur even if the effective cumulative diameter of the inflated balloons does not exceed the mentioned expansion limit of stents. Intravascular imaging is a helpful modality to define type of SF and its management. [ABSTRACT FROM AUTHOR]