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(1) Background: Modern imaging methods and constantly developing technologies extend the range of diagnostic tools in medicine and in orthodontics. Thanks to them, scientists and doctors can use devices designed to diagnose 3D structures of the human body. The aim of the study was to assess the usefulness of digital orthodontic models as a diagnostic tool in the work of an orthodontist through a comparative analysis of the value of orthodontic measurements made on traditional plaster models and virtual models. (2) Methods: A total of 80 sets of models were made, including 40 sets of plaster models and 40 sets of digital models. A total of 48 diagnostic parameters were developed. They concerned dental parameters. (3) Results: Comparative analysis of crown height values on plaster and digital models showed statistically significant differences (p < 0.05) in 26 out of 48 dental parameters. (4) Conclusions: The differences between the measurements made with the software on the digital models and the measurements made with the traditional method of measurement using the digital caliper on the plaster models were small and clinically acceptable. [ABSTRACT FROM AUTHOR]

Binder jetting (BJ) is an additive manufacturing technology that realizes mineral or metallic parts without support material and avoiding critical issues due to thermal phenomena. Because of these benefits, this technology is suitable for rapid tooling applications, as well as for casting process to produce complex moulds made for instance in plaster and organic compound as binder. Regarding the latter application, it is worth noting that chemical reactions can occur when the mould is in contact with molten metal, leading to the formation of gas and therefore porosity in the cast part. To limit this phenomenon, a burnout cycle is usually required before pouring the molten metal. In this research, the burnout temperature and time were investigated, as well as the pre-heating mould temperature before metal pouring in case of simple and complex part geometries. Three different levels of each studied parameters were tested, and the results were analysed in terms of casting defects. Results highlight that a burnout treatment performed at 250 °C for 6 h guarantees the best compromise in terms of casting soundness. [ABSTRACT FROM AUTHOR]

Heat dissipating non-calcined mixture (IVA) and sensible thermal heat storage calcined mixture (IVB) along with their composite materials with decorating paint, resin based black paint used in solar flat plate collector, CaCO3 with adhesive glue (Fevicol) and wall care putty have been synthesized in atmospheric condition. Differential scanning calorimetric (DSC) study was carried out at constant ramp rate of 10 K min−1 in atmospheric condition. From DSC, it was found that IVA exhibits exothermic behavior and IVB endothermic. The composite material (IVBDP) of IVB with decorating paint shows heat repellent behavior during cooling and endothermic behavior during heating. The composite materials (IVAWCP & IVBWCP) of both IVA and IVB with wall care putty, and composite material (IVBCaG) of IVB with CaCO3-adhesive glue were synthesized and thermal behavior of the same studied using DSC. In the composite material (IVBSP) of IVB with solar paint, the specific heat capacity increases by 3.57%. [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.)

The current context regarding the management of waste obtained from the construction industry, according to European Union laws and directives, requires the imposition of an integrated waste management system. The main objective of this study was to integrate and reuse old plaster waste as a substitute for aggregates in significant proportions in mortar composition and analyzing the impact on the physical and mechanical characteristics of mortar in fresh state and in hardened state. Over periods of 7, 14, and 28 days, the experimental program studied three types of plastering mortars: a standard recipe (without waste) and another two proposed recipes, in which construction waste was re-used as a substitute for aggregates in proportions of 10% and 15%. Results obtained on the fresh properties of the proposed plastering mortars (apparent density, consistency, and segregation trend) indicated a variation (increase/decrease) of 1% to 2.5% compared with the standard recipe. Mechanical strengths showed decreased values; that is, the compressive strength decreased by 11.09% and the flexural strength decreased by 22% when waste replaced aggregates in a proportion of 15%. The results of the experimental program identified the potential of waste plaster, which can replace up to 15% of the aggregates in plaster mortars, which still guarantees their successful use in practice. To reduce the influence of the use of waste on the mechanical strengths, we propose to conduct further investigations (nuclear magnetic resonance, electronic microscopy, and X-ray diffraction) on these mortars reinforced with different types of fibers. The large amount of waste resulting from the rehabilitation of damaged building facades and the fact that there are currently no experimental studies on the reuse of waste from old plaster mortars were the main reasons for the present study examining the possibility of their use in the production of new building materials. [ABSTRACT FROM AUTHOR]

Energy-efficient retrofitting of building envelopes is necessary to reduce global carbon emissions and to reach net-zero goals. Cooling energy demand-dominated countries in the GCC region require simple and effective strategies to reduce building sector energy loads. One such approach is using high solar reflective index (SRI) paints to retrofit building roofs and walls. However, the hot and desert conditions of the region pose a barrier to maintaining consistent radiative properties throughout their life cycle. To this extent, research is limited in the region. The novelty of this work is to qualitatively assess the aging characteristics of high SRI or cool paints and estimate the energy savings for their application in residential buildings. The work encompasses comprehensive lab, pilot, and real-scale experimental studies combined with theoretical modeling for dynamic evaluation. Dynamic simulations enabled to determine the time-dependent aging effect on the energy savings performance of the building retrofitted with cool roof and wall paints. A case study on a townhouse in UAE showed annual energy savings of 34% considering cool roofs, walls, and window films. Aging studies showed SRI reduction of 36% and 25%, respectively, for cool roofs and walls during the first 3 years. The corresponding energy-saving reductions ranged from 31 to 44% for the white roof to dark wall colors. Using the initial values of SRI in energy models overestimates saving by 10% per year. Considering the aging effects, this work provides insights into cool paint retrofit potential on energy, economic savings, and CO2 reductions for four major cities in the GCC region. [ABSTRACT FROM AUTHOR]

Polyurethane-based materials, which are widely used in exterior cladding, pose a great risk for buildings because they can easily catch fire at temperatures as low as 50–65 °C. Thus, different materials are needed to ensure that structures exposed to high temperatures do not have any stability problems. In this study, expanded perlite aggregate plaster (EPAP) was produced to eliminate the negative effects that may occur in buildings exposed to high temperatures. High temperature tests were carried out on test plates of different thicknesses to determine the effect of plaster thickness under high temperatures. In order to compare the effects of high temperatures, a test sample of normal aggregate plaster (NAP), which is widely used in buildings, was prepared. In the high temperature test, the temperature values on the back surfaces of the EPAP (≈115 °C) test plates were approximately 3 times lower than the temperature values of the NAP (≈350 °C) test plate. It can be said that structural stability loss and durability problems may occur in structures covered with NAP in a high-temperature environment, and that no negative effect will occur in terms of structural stability and durability problems in structures covered with EPAP in high temperature environments. [ABSTRACT FROM AUTHOR]

The focus of this paper is to determine whether it is possible to detect historical casting techniques on figural copies and distinguish differences due to these techniques from those caused by environmental influences after exposure to the weather. The figures from the Fürstenportal of Bamberg Cathedral of St. Peter and St. George, part of a UNESCO World Heritage site, have experienced much deterioration since the portal was erected in the early 13th century. For this reason, the jamb figures were moulded at the beginning of the 19th century and plaster copies made. These copies remained in safekeeping for over 90 years until they were used to make stone cast copies in the late 1990s. The copies replaced the outdoor originals, which were moved to a museum to protect them from further decay. It is therefore possible to observe different temporal states of the figures. Details of the moulding process could be identified with a workflow consisting of high-resolution 3D scanning, 3D surface comparisons and archival research. The plaster copies and the stone cast copies show different traces of the casting process. Both used flexible materials in the moulding process, which caused the copy to slightly deform from the originals. Furthermore, environmental influences could be separated from the moulding phenomena. Erosion from more than 90 years between the creation of the plaster copy and the translocation of the originals to the museum was observed, as well as erosion from the last 20 years on the stone cast copies. [ABSTRACT FROM AUTHOR]

The origin of the stone industry in Belgium goes back as far as the Roman occupation. The marble industry, with the oldest pieces of testimony, goes back to the 16th century. The marble workshops were located in the South of Belgium and even at this period the main customers were abroad: France, Britain and its Empire, in the States… The realization of a sculpture in natural stone, as the marble, asks rigor and method in direct link with the material because each small modification on the marble is permanent. The plaster cast is used as a reference point during the work and allows the transfer from the model in plaster to the marble. One of the most important workshops in Rance, worked for years to answer to the orders of sculptures of customers from the different countries. Most of the plaster casts, in connection with the large past work were discovered (recently) and offered at the museum.

Eco-friendly plasters offer several advantages, including sustainability, nontoxicity, and low cost. These plasters are made with sustainable materials, such as natural fibers and starches. These materials can have different mechanical properties compared to traditional plasters, which are made with gypsum and cement. Due to the increased attention being paid to environmental issues, efforts are still being made to switch out the conventional plaster of gypsum and cement for an eco-friendlier alternative to minimize toxicity, increase effectiveness, and lower cost. In this study, the effect of novel plaster behavior under pressure on mechanical properties was investigated. The plaster investigated was an eco-friendly carbon-free BSCO plaster. A range of experimental techniques were used, such as compression testing for confirmation using ANSYS 2023 R1 software, which set ergonomic and user-friendly standards as a minimum requirement, with the overarching goal of creating stronger, lighter, and more reasonably priced structures. The results showed that eco-friendly Bilateral Specialized Company (BSCO) plasters could have comparable mechanical properties to traditional plasters. Additionally, it is suggested that eco-friendly and carbon-free plasters can be a viable alternative to traditional plasters in a variety of applications. Researchers and civil engineers can both gain from this scientific paper’s potential to replace conventional stucco with an ecologically friendly alternative that has more effective mechanical qualities.

Abstract Background Paediatric fractures are highly prevalent and are most often treated with plaster. The removal of plaster is often an anxious experience for children. Virtual reality (VR) has proven to effectively distract children and reduce their anxiety in other clinical settings. This study aims to investigate the effect of VR on the anxiety level of children with fractures that undergo plaster removal or replacement in the plaster room. Methods This study is designed as a randomised controlled trial (RCT). The sample size is 270 patients, aged 5 to 17 years, with a fracture of the upper or lower extremity treated with plaster. The intervention group will be distracted with VR goggles and headphones during the replacement or removal of the plaster, whereas the control group will receive standard care. As a primary outcome, the level of anxiety will be measured with the Child Fear Scale (CFS). Secondary outcomes include anxiety reduction (difference between CFS after and CFS before plaster procedure) and Numeric Rating Scales (NRS) pain and satisfaction. Additionally, the children’s fastest heart rate during the procedure will be recorded. An unpaired samples t-test or a Mann-Whitney U test (depending on the data distribution) will be used to analyse the data. Discussion When completed, this trial will provide evidence on the potential role of VR in children with fractures treated with plaster. The purpose is to increase the quality of healthcare by decreasing anxiety and possibly pain perception of children during a plaster procedure. Trial registration Netherlands Trial Register NL9065 . Registered on 27 November 2020

Background: The aim of the present study was to investigate the accuracy of a new digital impression system, comparing it to the plaster impression technique in the realization of full-arch implant-supported metal frameworks. Methods: We took 11 scans (8 of the upper maxilla and 3 of the lower jaw) on a sample of nine patients previously rehabilitated with fixed full-arch screw-retained prostheses following the Columbus Bridge Protocol (CBP) with four to six implants (total: 51) since at least 4 months. Two impressions were taken for each dental arch: one analogic plaster impression using pick-up copings and an open tray technique and a second one using an intra-oral scanner. Two milled metal substructures were realised. The precision and passivity of the substructures were clinically analysed through the Sheffield test and endo-oral radiographs. Laboratory scans of the plaster casts obtained from an intra-oral scanner (IOS) and of the plaster casts obtained from traditional impression were compared with the intraoral scans following Hausdorff's method and an industrial digital method of optical detection to measure discrepancies. A Mann–Whitney test was performed in order to investigate average distances between surfaces after the superposition. Results: The Sheffield test demonstrated an excellent passivity of the frameworks obtained through both the digital and the analogic method. In 81.81% of cases (n = 9) both substructures were found to have a perfect fit with excellent passivity, while in 18.18% (n = 2) of cases the substructures were found to have a very slight discrepancy. From the radiographic examination, no gaps between the frameworks and the implant heads or multiunit abutments were observed, with 100% accuracy. By superimposing digital files of scans according to Hausdorff's method, a statistically significant discrepancy (p = 0.006) was found between the digital scans and the digital models obtained from plaster impressions. Three-dimensional optical detection found a mean discrepancy of 0.11 mm between the analogic cast and the cast derived from the digital impression. Conclusions: The present study clinically demonstrates that milled implant-supported full-arch frameworks obtained through a digital scan and the herein described technique have an accuracy comparable to those obtained with traditional plaster impression. [ABSTRACT FROM AUTHOR]

Masonry often requires strengthening to withstand against extreme actions such as earthquakes, cyclones and flooding. Recently, new methods have been developed to strengthen masonry, such as fabric reinforced cementitious matrixes and fibre reinforced polymers. However, other strengthening systems such as welded wire meshing (WWM), reticulatus and plastering with cementitious matrixes/mortar (CP) have been also practiced to reinforce masonry, conversely no systematic design guidelines are available for these methods. In this study, an attempt has been made to establish rational design approaches to predict the shear resistance of WWM, reticulatus and CP methods. Three sets of experimental database have been developed for design verification. The effectiveness of these strengthening methods was appraised by comparing their structural performances. The available formulations to predict the shear resistance of unreinforced masonry (URM) and CP strengthened masonry were assessed against the established database, and suitable modifications were proposed to effectively account the contribution of cementitious matrix. A unified approach to estimate the shear strength was proposed based on the contribution of URM, CP and reinforcements. The design approach is shown to conservatively predict the shear strength of strengthened masonry. [ABSTRACT FROM AUTHOR]

Material structures organised in pairs were significant features within shrines and special buildings of the Near Eastern Epipaleolithic and early Neolithic. These stone and plaster monuments came to bear defining humanoid features that possibly commemorated mythical brothers or twins. The twin god theme appears widely in ethnographies, and is used to define celestial luminaries, divisions of space and the opposing extremes of the seasonal year. Material and environmental evidence of the Pre-Pottery Neolithic phase of the Near East further indicates that these features, replete with early constellation images, monumentalise a calendar-informed cosmology and reveal a significant correlation between cultic monuments, social gatherings and times of the year. [ABSTRACT FROM AUTHOR]

Gypsum (GPS) has great potential for structural fire protection and is increasingly used in construction due to its high-water retention and purity. However, many researchers aim to improve its physical and mechanical properties by adding other organic or inorganic materials such as fibers, recycled GPS, and waste residues. This study used a novel method to add non-natural GPS from factory waste (phosphogypsum (PG)) as a secondary material for GPS. This paper proposes to mix these two materials to properly study the effect of PG on the physico-mechanical properties and fire performance of two Tunisian GPSs (GPS1 and GPS2). PG initially replaced GPS at 10, 20, 30, 40, and 50% weight percentage (mixing plan A). The PGs were then washed with distilled water several times. Two more mixing plans were run when the pH of the PG was equal to 2.4 (mixing plan B), and the pH was equal to 5 (mixing plan C). Finally, a comparative study was conducted on the compressive strength, flexural strength, density, water retention, and mass loss levels after 90 days of drying, before/after incineration of samples at 15, 30, 45, and 60 min. The results show that the mixture of GPS1 and 30% PG (mixing plan B) obtained the highest compressive strength (41.31%) and flexural strength (35.03%) compared to the reference sample. The addition of 10% PG to GPS1 (mixing plan A) improved fire resistance (33.33%) and the mass loss (17.10%) of the samples exposed to flame for 60 min compared to GPS2. Therefore, PG can be considered an excellent insulating material, which can increase physico-mechanical properties and fire resistance time of plaster under certain conditions. [ABSTRACT FROM AUTHOR]

Interest towards cellulose nanofibers obtained from virgin and waste sources has seen a significant growth, mainly thanks to the increasing sensitivity towards the concept of circular economy and the high levels of paper recycling achieved in recent years. Inspired by the guidelines of the green building industry, this study proposes the production and characterization of TEMPO-oxidized and homogenized cellulose nanofibers (TOHO CNF) from different sources and their use as additives for earth plasters on two different raw earth samples, characterized by geotechnical laboratory tests and mineralogical analysis: a high-plasticity clay (T2) and a medium-compressibility silt (ABS). Original sources, including those derived from waste (recycled cardboard and paper mill sludge), were characterized by determining chemical content (cellulose versus ashes and lignin) and fiber morphology. TOHO CNF derived from the different sources were compared in terms of nanofibers medium diameter, crystallinity degree, thermal decomposition and oxidation degree, that is the content of carboxylic groups per gram of sample. Then, a preliminary analysis of the influence of CNF on earth plasters is examined. Adhesion and capillary absorption tests highlighted the effect of such nanofibers on blends in function of two factors, namely the cellulose original source and the oxidation degree of the fibers. In particular, for both earth samples, T2 and ABS, a significant increase in adhesion strength was observed in the presence of some TOHO CNF additives. As far as capillary sorption tests, while an undesired increase in water adsorption was detected for T2 compared to the control, in the case of ABS, a significant reduction in water content was measured by adding TOHO CNF derived from recycled sources. These results pave the way for further in-depth investigation on the role of TOHO CNF as additives for earth plasters. [ABSTRACT FROM AUTHOR]

Architectural ornaments, used as decorative elements, are made of stone; but most of their components contain gypsum. It is found that the deterioration of ornaments is attributed to water penetration, biological colonization, micro and macro cracking and partial and (or) complete detachment from their supports. Many rehabilitation operations of architectural ornaments have failed to use the appropriate material for the needs of the project. The use of construction waste, particularly used brick, is currently widespread for such operations. For an efficient and sustainable use of these materials, an experimental study was conducted to investigate the influence of the content of waste brick on the physical and mechanical properties of gypsum mortar. The main variables in this study being the waste brick content and the substrate type. The Water/Mortar ratio of all mixes was kept constant to maintain a similar level of workability. Numerous tests were performed to evaluate the physical and mechanical behavior of the gypsum mortars, including bond test, X-ray and SEM analysis. The results obtained show that the bond strengths of the mortars are greater when the substrate is made of limestone compared to the substrate made of bricks. However, an excessive percentage of brick waste in the mortar can have negative effects and reduce the bond strength. Plaster mortars made with 75% waste brick should be recommended for the rehabilitation of architectural ornaments. [ABSTRACT FROM AUTHOR]

The annealing process in FDM printing applying materials such as PLA and HTPLA, is a technique that looks for the improvement of the mechanical characteristics of post-printing products. The aim of the research is to determine the most suitable annealing process that does not generate significant changes in the dimension of the object. To this end, 108 test pieces were manufactured within the applied methodology, which were exposed to combined tests that considered variables such as the type of printing material, the fill level, temperature and coating. Once the experiment was carried out, it was concluded that the most suitable annealing process is in PLA or HTPLA material at 100% filler, exposed to 200°C with plaster stone coating. [ABSTRACT FROM AUTHOR]

Disclosing the composition of mortars and plasters adopted in antiquity is of crucial importance from a historical point of view, both to assess the technological knowledge of a given civilization and also from the point of view of conservation of the historical artefacts to proceed with the most appropriate methodologies for conservation. This work intends to increase the analytical capabilities of the specialists to ensure an increasingly accurate and detailed analysis of the characteristics of the mortars used in ancient times. To this aim, the increasingly appreciated and adopted approach in digital image analysis (DIA) has been added to the petrographic study in thin section to obtain a more accurate quantification of the components of the mortar mixtures (binder/aggregate B/A ratio). The approach was carried out on well-known building materials from the Temple of Venus of Pompeii, in particular on stratified plasters whose sequence was found to be particularly recurrent in the materials taken into account during the archaeological investigations. The study revealed a good correspondence between traditional microscopic quantification techniques and digital image analysis, thus guaranteeing the truthfulness of the data obtained through the latter methodology. It also pointed out discrepancies related to the image processing and image types that should be consciously consider when applying this quantitative method. At the same time, however, greater accuracy was found in the data obtained from the DIA. [ABSTRACT FROM AUTHOR]

• First in-situ assessment of plasters with mixed-in salt crystallization inhibitor. • Long-term monitoring of decay, moisture and salt content in plasters. • The inhibitor reduces salt-induced decay (sanding) in lime-based plaster. • Surface discoloration & transport of inhibitor to surface occurs in lime plaster. • Possible solutions for discoloration and leaching of inhibitor are proposed. Salt crystallization is a major cause of weathering of mortars, including plasters and renders. In the last decade, the use of mixed-in salt crystallization inhibitors in mortars has been proposed as a solution to improve the durability of this material with respect to salt decay. Laboratory characterization and accelerated weathering tests have shown encouraging results. However, data on the long-term behaviour of these mortars when applied on-site were missing until now. In this research the durability with respect to salt decay of a lime-based plaster and a salt accumulating plaster has been assessed. These plasters, with and without sodium ferrocyanide, a well-known inhibitor of sodium chloride crystallization, have been applied to an interior brick masonry wall with a high salt (sodium chloride) and moisture load and monitored for a period of 4 years. Monitoring included visual and photographic observations of the damage as well as measurements of the moisture and salt content and distribution, both in the wall and in the plaster. Moreover, the content and distribution of the inhibitor in the plaster after 4 year exposure was measured, to gain insight into the dissolution and transport of the inhibitor. The results of the research clearly show that the inhibitor is able to significantly reduce the occurrence of salt-induced decay in the lime-based plaster, in comparison to the plaster without inhibitor. No conclusions can be drawn in the case of the salt accumulating plaster, as no decay has developed yet in this case. Two issues related to leaching of the inhibitor and surface discolouration have emerged. These are discussed and possible solutions are proposed. [ABSTRACT FROM AUTHOR]

Non-destructive analysis techniques became an important approach for the characterisation of cultural heritage and conservation science. In this study, for the first time, Synchrotron-based X-ray Fluorescence (SRXRF) analysis, at the Synchrotron-light for Experimental Science and Applications in the Middle East (SESAME), was utilized to examine and analyze three Byzantine plaster figurines from Jordan Museum. Analysis was applied to identify the main composition of the body, the black drawings on the figurines and the mirror fragment on one of the objects. The results showed that the matrix of the body is composed of Calcium carbonate (plaster) and other inclusions were added to facilitate setting of the lime during hydrating. The black drawing on the objects was identified as wooden charcoal. Finally, results showed that the mirror is not a silicon based but a highly polished surface material composed of manganese (Mn), galium (Ga) and lead (Pb). [ABSTRACT FROM AUTHOR]

Fuel electrode-supported tubular protonic ceramic cells (FETPCCs) based on the BaZr0.4Ce0.4Y0.15Zn0.05O3−δ (BZCYZ) membrane electrolyte was fabricated through a two-step method, in which the polyporous electrode-support tube was prepared with a traditional slip casting technique in a plaster mold, and the BZCYZ membrane was produced by a dip-coating process on the outside surface of the electrode-support tube. The dense thin-film electrolyte of BZCYZ with a thickness of ~25 μm was achieved by cofiring the fuel electrode support and electrolyte membrane at 1450 °C for 6 h. The electrochemical performances of the FETPCCs were tested under different solid oxide cell modes. In protonic ceramic fuel cell (PCFC) mode, the peak power densities of the cell reached 151–191 mW·cm−2 at 550–700 °C and exhibited relatively stable performance during continuous operation over 100 h at 650 °C. It was found that the major influence on the performance of tubular PCFC was the resistance and cathode current collectors. Additionally, in protonic ceramic electrolysis cell (PCEC) mode, the current densities of 418–654 mA·cm−2 were obtained at 600–700 °C with the applied voltage of 2.0 V when exposed to 20% CO2–80% H2 and 3% H2O/air. Using distribution of relaxation time analysis, the electrolytic rate-limiting step of the PCEC model was determined as the adsorption and dissociation of the gas on the electrode surface. [ABSTRACT FROM AUTHOR]

Construction workers are found to use Personal Protective Equipment (PPE) infrequently, although workplace accidents are common and strongly associated with safety education. In Ho, Ghana, this study examines POP installers' awareness of occupational hazards and the use of PPEs. The study's motivation and contribution are in its analysis of the perceived obstacles and driving forces behind PPE use by POP installers in the construction industry, which is yet unknown in Ghana. Between May 15 and June 30, 2022, 149 POP installers in Ho Municipality filled out a crosssectional questionnaire using a purposive sampling method, and the data were analysed using the Statistical Package for Social Science (SPSS) v.20. The outcome variables were determined using logistic regression with a 0.05 p value, the relative importance index (RII), and correlation analysis. There is a lack of awareness of knowledge, PPE use, and workplace safety among the participants. Once again, respondents cited discomfort as a reason for not wearing PPE during POP installation. Furthermore, knowledge of occupational hazards among POP workers negatively predicts PPE usage (B = 0.207, p < 0.05). The study's findings provide critical information for contractors' associations to collaborate with relevant health and safety professionals to regularly organise safety awareness training for members to increase worker knowledge and reduce risk-taking behaviour. This study is unique because it is the first to access and provides an in-depth analysis of the purported barriers and driving motivations for PPE compliance and noncompliance from the perspective of an under-researched group of construction workers in Ghana. [ABSTRACT FROM AUTHOR]

The present study aims to study the effect of fermented rice husk (RH) on earth plaster for coating and improving the durability of adobe walls. The mixtures of clayey earthen materials and 0%, 33%, 50%, and 67% of fermented RH of the total volume of the mixture are studied to assess their physicomechanical and durability properties. The RH is previously fermented separately in water for the periods of 2, 3, and 3 weeks. The pastes obtained after mixing the clayey earth material and fermented RH were used to mold 4 × 4 × 16 cm³ test specimens. The specimens were dried under ambient laboratory conditions ð32 ± 5℃ and 35±5%HR) for 21 days before their characterization. The clay earthen material mainly contains silt (51%), clay (24%), sand (23%), and gravel (3%). It has a liquidity limit, plasticity index, and methylene blue value of 32%, 20%, and 2.66, respectively. The results show that apparent density, linear shrinkage, resistance to compression, and the thermal conductivity of the plaster specimens, respectively, decrease from 1.88 to 1.07 g/cm³, 4.52 to 0.83%, 3.88 to 0.82 MPa, and 0.87 to 0.05 W/m.K with increasing volumetric content of RH from 0% to 67%. Moreover, the resistance to abrasion increased. The resistance to capillary water absorption and water erosion was deficient for the content of RH above 50%. The mixture containing up to 33% of RH allows to improve engineering performances and reaches acceptable durability and would therefore be useful for coating adobe walls. [ABSTRACT FROM AUTHOR]

The twenty-second excavation season of the Archaeological Expedition to Wad Ben Naga focused on the continued exploration of the so-called Isis Temple (WBN 300). The works covered the south-eastern part of the hypostyle hall (WBN 301), a part of the central vestibule (WBN 302) including its front entrance, the entire southern vestibule (WBN 310), and a large part of the southern corridor (WBN 312). The excavation in the hypostyle hall yielded most notably many fragments of columns and a complete abacus with relief decoration, which allowed for partial reconstruction of their decorative scheme. There were also many pieces of modelled and painted plaster fragments apparently coming from the southern tower of the pylon and depicting King Natakamani and the god Horus. The stone-built entrance from the hypostyle hall to the central vestibule was found to be covered with relief depictions of King Natakamani and Queen Amanitore and Egyptian hieroglyphic texts. The southern vestibule and the southern corridor were recognised to have had painted decoration, which was especially well preserved in the southern corridor. Besides the paintings, a stairway leading to the roof of the building and a later burial of a non-adult individual were located there as well. [ABSTRACT FROM AUTHOR]

Copyright of Conservar Património is the property of Associacao Profissional de Conservadores-Restauradores de Portugal 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 Ge-Conservación is the property of Instituto del Patrimonio Cultural 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 GRID - Architecture, Planning & Design Journal is the property of GRID - Architecture, Planning & Design Journal 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 TÜBA-AR: Turkish Academy of Sciences, Journal of Archaeology is the property of Turkish Academy of Sciences 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 Plurentes is the property of Universidad Nacional de La Plata 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.)

Purpose: The present study aimed to assess the accuracy and reproducibility of laser-scanned digital models compared to plaster models. Materials and Methods: A total of 50 plaster models were scanned using the 3M ESPE Lava scan ST scanner to construct digital models. Various measurements, encompassing intra-arch and inter-arch from scans and plaster models, were estimated. The plaster models were measured using digital calipers and digital models using MiniMagics 3.0 software. Descriptive statistics were calculated, and the mean difference of the parameters between the two groups was tested by paired t-test. Results: No significant difference was detected between the digital and manual measurements in the majority of the parameters, and the values for the parameters showed significant differences that were not clinically applicable. The digital method showed good reproducibility for all the measurements (r > 0.7). Overbite showed a marked variation between the manual and digital measurements due to overlapping tooth structures in digital models with respect to ideal occlusion. Bolton's analysis did not show a significant difference between the manual and digital methods. Conclusions: Digital models could be compared to the gold standard plaster models. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologia Historica is the property of Masaryk University, Faculty of Arts 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.)

Clay bricks are one of the most widely used materials in building construction due to their advantages, including local availability, ease of fabrication and cost‐effectiveness. Fire is one of the dangerous hazards that can cause damage the life and property. Lightweight plasters play a vital role in insulating the masonry construction during fire accident. There is only limited data and information available on the fire performance of Clay Brick Masonry (CBM) insulated with lightweight plaster. An extensive investigation was undertaken to evaluate the residual strength properties and physical characteristics of CBM prisms exposed to elevated temperatures. CBM prisms plastered with M‐sand mortar, vermiculite mortar, and perlite mortar were used for the investigation. Protected prisms were exposed to elevated temperatures following the ISO 834 standard fire curve for durations of 30 min (821°C), 60 min (925°C), 90 min (986°C), and 120 min (1029°C). Mechanical properties such as axial load carrying capacity, stress–strain behaviour, elastic modulus, and crack pattern were examined. The mechanical properties of CBM prisms were found to be highly influenced by the type of plastering, intensity, and the duration of heating. The microstructure and image analysis confirmed the effects of temperature exposure on protective plasters. Equations are proposed to determine the residual axial compressive strength and the elastic modulus of CBM. It was found that the specimens plastered with perlite mortar had better fire resistance. [ABSTRACT FROM AUTHOR]

The primary protection against the charring of timber is ensured by protection materials. Today, there are only a limited number of materials given in design codes as fire protection materials for timber. Historic surface finish materials such as plasters have rarely been studied with respect to fire; no design values exist in the current fire part of Eurocode 5. Full‐scale fire testing is costly to assess the fire performance of material combinations, thus this study presents a useful tool that is specifically tailored to evaluate the fire protection ability of materials in small‐scale. A review of conducted tests demonstrate that the cone heater of a cone calorimeter is a dependable device to estimate the charring performance of protected timber specimens as the test results approximate the ones obtained from furnace tests. This work contributes to the assessment of fire resistance performance of various combinations and types of plaster systems found in existing timber buildings that often require an individual approach for an adequate fire risk analysis and design decisions to meet current fire safety regulations with respect to the load‐bearing capacity and compartmentation of building structures. Increased knowledge on the fire protection performance of traditional plasters is believed to facilitate their wider use in timber buildings, primarily to preserve their significance as part of the cultural built heritage. [ABSTRACT FROM AUTHOR]

Estimating the amount of material without significant losses at the end of hybrid casting is a problem addressed in this study. To minimize manufacturing costs and improve the accuracy of results, a correction factor (CF) was used in the formula to estimate the volume percent of the material in order to reduce material losses during the sample manufacturing stage, allowing for greater confidence between the approved blending plan and the results obtained. In this context, three material mixing schemes of different sizes and shapes (gypsum plaster, sand (0/2), gravel (2/4), and Posidonia oceanica fibers (PO)) were created to verify the efficiency of CF and more precisely study the physico-mechanical effects on the samples. The results show that the use of a CF can reduce mixing loss to almost 0%. The optimal compressive strength of the sample (S1B) with the lowest mixing loss was 7.50 MPa. Under optimal conditions, the addition of PO improves mix volume percent correction (negligible), flexural strength (5.45%), density (18%), and porosity (3.70%) compared with S1B. On the other hand, the addition of PO thermo-chemical treatment by NaOH increases the compressive strength (3.97%) compared with PO due to the removal of impurities on the fiber surface, as shown by scanning electron microscopy. We then determined the optimal mixture ratio (PO divided by a mixture of plaster, sand, and gravel), which equals 0.0321 because Tunisian gypsum contains small amounts of bassanite and calcite, as shown by the X-ray diffraction results. [ABSTRACT FROM AUTHOR]

The control of moisture in the building sector represents a widespread issue and research topic, in terms of improving the quality of indoor space healthiness and energy performance. In Venice, rising damp and moisture phenomena are very diffused and difficult to solve, due to building structures and specific environmental conditions. All of the buildings and artefacts in the city are presently wall structures filled with bricks, which lean on relatively permeable soil, are exposed to an environment rich in saline aerosols, and are continuously lapped by floods and brackish water. The aim of this research was to analyze typical Venetian masonry walls affected by rising damp through the application of non-destructive methods, in order to understand and assess the behavior of construction materials in specific boundary conditions. The data given by non-destructive monitoring in mock-up masonries were compared with dynamic simulations to estimate the hygrothermal behavior and analyze the effect on different parameters, such as the physical properties of new and historical materials (i.e., density, thermal conductivity, etc.), the presence and type of plasters, and the kinds of traditional treatment applications. The evaluation of experimental data, supported by simulations provides to the literature an empirical comprehension of rising damp phenomena in real masonry toward careful heritage conservation. [ABSTRACT FROM AUTHOR]

This article examines a group of previously unpublished floor plaster fragments together with architectural and stratigraphic evidence from the Main Building of the Palace of Nestor at Pylos. Analysis of the plaster shows that the fragments formed part of the floor of upper-story rooms, which fell during the building's structural collapse. This study confirms an earlier hypothesis that the majority of the Main Building carried an upper story and also indicates that the palatial megaron did not have an upper story or balcony. The evidence from Pylos is considered in light of Late Bronze Age comparanda, allowing for a revised reconstruction of the Mycenaean palatial megaron. [ABSTRACT FROM AUTHOR]

Copyright of EU-topías: A Journal on Interculturality, Communication & European Studies is the property of Universite de Geneve, Global Studies Intitute 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.)

Introduction: The radial forearm free flap (RFFF) is a commonly used free flap for the reconstruction of orofacial defects because of its versatility and reliability. The donor site is closed with either split or full-thickness skin graft, and one of the common donor site morbidities is skin graft failure. Various techniques to minimise skin graft failure were reported, and we compared the skin graft techniques with and without plaster back slab dressing in the radial forearm donor site. Materials and Methods: This is a retrospective study of 75 patients who had RFFF for reconstruction of oral cavity cancer at two different tertiary teaching hospitals in the United Kingdom between April 2015 and March 2020. Thirty-nine patients from Hospital one had volar back slap, bolster dressing and crepe bandage. In contrast, 36 patients from Hospital two had only pressure dressing without a back slab. Results: The mean age of the study population was 60.65 (P = 0.274). In both groups, two patients had donor site complications. However, there was no significant difference in the donor site skin graft complications with a P = 0.662. Discussion: There was no evidence in the literature to support an ideal bandage for skin graft at the RFFF donor site. Our comparison of two techniques of skin graft dressings with and without back slap did not show any difference in the skin graft take, and the volar back slab did not add any additional benefits. The simple use of foam as a bolster dressing without a back slab is ideal for the radial forearm free flap donor site. [ABSTRACT FROM AUTHOR]