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1.
Cureus ; 16(8): e66029, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39221297

RESUMEN

Monolithic zirconia is widely used in dentistry due to its outstanding mechanical properties, biocompatibility, and aesthetic qualities. This review examines how different polishing and finishing methods impact the performance and appearance of monolithic zirconia restorations. Derived from zirconium, zirconia is a robust ceramic that exists in monoclinic, tetragonal, and cubic forms, with properties that prevent crack propagation. Monolithic zirconia, preferred over porcelain-fused-to-metal (PFM) crowns, offers better aesthetics and avoids chipping. Various surface treatments, such as polishing and glazing, enhance zirconia's smoothness and wear characteristics. Polished zirconia is less abrasive to enamel than glazed zirconia, making it more suitable for opposing teeth. Research indicates that polished zirconia has a smoother surface and higher fracture resistance compared to other dental ceramics. Surface roughness, which is influenced by the treatment method, is crucial in minimizing wear on opposing teeth. Polished monolithic zirconia also shows high flexural strength, chipping resistance, and translucency. While both polishing and glazing reduce brightness, polishing better preserves translucency. The literature identifies polishing as the best post-processing method for enhancing zirconia's surface quality and mechanical properties without compromising its load-bearing capacity. In conclusion, polishing and finishing significantly improve the aesthetic and clinical performance of monolithic zirconia, confirming its effectiveness for durable and visually appealing dental restorations.

2.
Pediatr Allergy Immunol ; 35(9): e14231, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39254357

RESUMEN

BACKGROUND: Consumption of ultra-processed foods [UPFs] may be associated with negative health outcomes. Limited data exist regarding the potential role of UPFs in the occurrence of allergic diseases. The underlying mechanisms underpinning any such associations are also poorly elucidated. METHODS: We performed a systematic review and narrative evidence synthesis of the available literature to assess associations between UPF consumption and pediatric allergy outcomes (n = 26 papers), including data on the association seen with the gut microbiome (n = 16 papers) or immune system (n = 3 papers) structure and function following PRISMA guidelines. RESULTS: Dietary exposure to fructose, carbonated soft drinks, and sugar intake was associated with an increased risk of asthma, allergic rhinitis, and food allergies in children. Commercial baby food intake was associated with childhood food allergy. Childhood intake of fructose, fruit juices, sugar-sweetened beverages, high carbohydrate UPFs, monosodium glutamate, UPFs, and advanced glycated end-products (AGEs) was associated with the occurrence of allergic diseases. Exposure to UPFs and common ingredients in UPFs seem to be associated with increased occurrence of allergic diseases such as asthma, wheezing, food allergies, atopic dermatitis, and allergic rhinitis, in many, but not all studies. CONCLUSION: More preclinical and clinical studies are required to better define the link between UPF consumption and the risk of allergies and asthma. These observational studies ideally require supporting data with clearly defined UPF consumption, validated dietary measures, and mechanistic assessments to definitively link UPFs with the risk of allergies and asthma.


Asunto(s)
Hipersensibilidad a los Alimentos , Humanos , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/etiología , Niño , Comida Rápida/efectos adversos , Microbioma Gastrointestinal/inmunología , Asma/epidemiología , Asma/etiología , Asma/inmunología , Manipulación de Alimentos , Rinitis Alérgica/epidemiología , Rinitis Alérgica/etiología , Preescolar , Comités Consultivos , Alimentos Procesados
3.
J Esthet Restor Dent ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39228147

RESUMEN

OBJECTIVE: The purpose of this in vitro study was to evaluate the effect of staining, glazing, and polishing on the survival probability of monolithic crowns manufactured with preshaded stabilized zirconia with 5 mol% of yttrium oxide (5Y-TZP). MATERIALS AND METHODS: Monolithic crowns in the shape of an upper canine (1.5 mm of thickness) were manufactured by CAD/CAM, adhesively cemented on metallic foundation, and divided into 6 groups (n = 21): C (control), S (staining), G (glazing), P (polishing), SG (staining and glazing), and SP (staining and polishing). The survival probability was determined by step-stress accelerated life testing with a load applied to the palatine concavity of the crown. First, the specimens were subjected to a single-load to fracture test (SLF) and next to the fatigue test (5 Hz, thermocycling immersed in water varying 5-55°C), including the light (n = 9), moderate (n = 6), and aggressive (n = 3) loading profiles (load ranged between 20% and 60% of SLF). The survival probability was calculated considering the cycles for failure (CFF) and fatigue failure load (FFL) and illustrated using a Kaplan-Meier graph. The comparison among groups was performed using a Log-Rank test (α = 0.05). RESULTS: The mean value of SLF was 586.7 N. There was no difference among groups in survival probability, considering CFF and FFL. CONCLUSION: Staining, glazing, and polishing can be performed safely without damaging the mechanical behavior of 5Y-TZP monolithic crowns. CLINICAL SIGNIFICANCE: Staining is used to characterize and improve the esthetic of zirconia monolithic crowns. It can be used to reproduce the color gradient in the cervical region of the crown and pigmented grooves. This study showed that staining, glazing, and polishing did not affect the survival probability and the use of finishing procedures (glazing or polishing) after staining did not improve the survival probability of zirconia monolithic crowns.

4.
BMC Oral Health ; 24(1): 1104, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289670

RESUMEN

BACKGROUND: The effect of an immune-boosting beverage (SAM) containing Sambucus Nigra, an energy beverage (ENE), an in-office bleaching (BLE) agent with 25% hydrogen peroxide superior, glazing (GLA) or polishing (POL) methods, and professional dental prophylaxis (PDP) on the color of CAD-CAM restorative materials is unknown. METHODS: In total 210 specimens were prepared, consisting of CAD-CAM feldspathic (FC), zirconia-reinforced lithium disilicate ceramic (ZLS) and hybrid ceramic (HC). The ceramic specimens were divided according to the polishing methods of glazing (GLA) and mechanical polishing (POL). All materials were divided into two groups: with and without BLE. A 25% hydrogen peroxide superior (HPS) gel was used for BLE. After the baseline (BAS) measurement, the specimens were immersed in 3 different beverages (distilled water (DIS), SAM, ENE). After 28 days, a fine-grained (RDA 7) prophylaxis paste was applied. Statistical analysis of ∆E00 color difference values was performed by 3-way ANOVA and Bonferroni test (α = 0.05). RESULTS: The effect of all other actions except material-BLE-beverage on color for BAS-Day 28 was statistically different (p < 0.05). The effect of material, material-BLE, beverage on color for Day 28-PDP was statistically different (p < 0.05). After 28 days, the lowest color change was found in FC-GLA and HC immersed in DIS (p = 0.0001) and the highest in FC-POL immersed in ENE (p = 0.0002). PDP was efficient in color recovery in HC immersed to DIS, ENE and SAM (p = 0.0010). For FC, HC and ZLS, BLE caused a higher color change (p < 0.0001). Regardless of the material, the highest color change for BLE-beverage was found in BLE-treated specimens immersed in ENE (p = 0.0496) and the lowest color change was found in non-BLE-treated specimens immersed in SAM (p = 0.0074). CONCLUSIONS: In materials pre-exposed to 25% HPS, the effect of PDP on color recovery was lower than in unexposed materials. After 28 days, mechanical polishing produced higher color change in FC than glazing, however, in ZLS effects of glazing and mechanical polishing on color were similar. For material/polishing method, HC was the most effective. ENE caused higher color change than DIS and SAM. PDP was more effective than ENE in restoring color to DIS- and SAM-immersed specimens.


Asunto(s)
Color , Pulido Dental , Peróxido de Hidrógeno , Peróxido de Hidrógeno/química , Pulido Dental/métodos , Bebidas Energéticas , Profilaxis Dental/métodos , Blanqueadores Dentales , Humanos , Ensayo de Materiales , Restauración Dental Permanente/métodos , Materiales Dentales/química , Blanqueamiento de Dientes/métodos , Cerámica/química
5.
Materials (Basel) ; 17(16)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39203225

RESUMEN

With the increasing global focus on energy efficiency and environmental sustainability, intelligent building materials such as thermochromic glazing have emerged as a hot topic of research. The intent of this paper is to explore the utilization of gel-type thermochromic glazing within the realm of architectural energy conservation calculations. It conducts an exhaustive examination of the material's attributes, its capacity for energy savings, and the obstacles encountered in real-world applications. Through simulation studies and case analyses, this paper assesses the energy efficiency of gel-type thermochromic glazing across various climates and suggests strategies for optimization. The study revealed that the incorporation of gel-based thermochromic glazing leads to a marked reduction in energy usage within buildings, an improvement in indoor comfort levels, and significant environmental advantages.

6.
J Dent ; 148: 105257, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-39043330

RESUMEN

OBJECTIVE: Evaluate the impact of a "fast" crystallization and simultaneous-glazing on the physicochemical properties of lithium-disilicate CAD/CAM-ceramic. METHODS: Lithium-disilicate bars and crowns (IPS e.max CAD, Ivoclar-Vivadent) were divided into four groups (n = 30): WG/F (WG=with glaze/F=fast crystallization), NG/F (NG=no glaze), WG/C (C=conventional crystallization), and NG/C. A liquid/powder glaze system was used (IPS Ivocolor®, Ivoclar-Vivadent). Specimens were crystallized (Programat P310, Ivoclar-Vivadent) using the P161 program for C (approx. 20-25 min), and P165 for F (approx. 14-16 min). Bars (n = 30) underwent three-point bending tests (flexural strength-FS in MPa and modulus of elasticity-E in GPa) using a universal testing machine. Crowns were analyzed via scanning electron microscopy (SEM) after selective etching, and to Raman, FTIR-ATR, and X-ray diffraction (XRD) spectroscopies to assess chemical composition. RESULTS: For FS, both factors/interaction were statistically significant. C (427.48±42.41 MPa) showed significantly higher values than F (409.82±38.82 MPa). WG (398.32±29.80 MPa) exhibited significantly lower FS than NG (438.21±41.77 MPa). For E data, both factors/interaction were significant. NG (90.28±14.71 GPa) displayed higher E than WG (83.07±5.69 GPa), while C (90.08±12.98 GPa) exhibited higher E than F (83.46±9.40 GPa). NG/C showed the best results for both variables. F groups showed (SEM) porous surfaces and crack-like marks on crystals. FTIR, Raman and XRD spectra confirmed the typical composition of a lithium-disilicate glass ceramic, and some attenuated signals and structural variations (XRD) in WG. CONCLUSIONS: "Fast" crystallization and simultaneous-glazing produced weaker/less-rigid structures with irregular crystals and glassy phases. Simultaneous glazing may have hindered proper thermal distribution during crystallization. SIGNIFICANCE: "Fast" crystallization and simultaneous glazing with non-recommended systems, can adversely affect the final properties of lithium disilicate restorations.


Asunto(s)
Cerámica , Diseño Asistido por Computadora , Coronas , Cristalización , Porcelana Dental , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Porcelana Dental/química , Cerámica/química , Espectroscopía Infrarroja por Transformada de Fourier , Análisis del Estrés Dental , Resistencia Flexional , Humanos , Módulo de Elasticidad , Difracción de Rayos X , Espectrometría Raman
7.
Materials (Basel) ; 17(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38473470

RESUMEN

The surface roughness (Ra) of indirect computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated dental restorations is crucial for their long-term durability. This study intended to evaluate the Ra of five different types of contemporary indirect CAD/CAM restorative materials with varying compositions that were glazed and finished/polished. A total of 75 specimens, disc-shaped (10 mm × 2 mm), were obtained from five materials (n = 15) (Tetric CAD, IPS e.max CAD, IPS e.max ZirCAD, CELTRA Duo, and Vita Enamic) and fabricated by CAD/CAM. One of the two surfaces for each specimen was subjected to glazing, while the other surface was subjected to finishing/polishing. The Ra of the two surfaces in micrometers (µm) was evaluated using a Profilometer, while the surface topography was examined using a scanning electron microscope. Using SPSS, the Kruskal-Wallis, post hoc Conover, and Mann-Whitney tests were used to statistically evaluate the data. A comparison of the Ra for the finished/polished surfaces of the five test materials showed significant differences (p < 0.0001). Among the finished/polished surfaces, the mean rank values of Vita Enamic were significantly higher than the other four test materials (p < 0.0001). A comparison of the Ra of glazed surfaces among the five study materials revealed significant differences (p < 0.0001). The Ra for the IPS e.max ZirCAD material was significantly higher than the rest of the four materials (p < 0.001). A comparison of the Ra for two types of surface conditioning within each of the five test materials showed a significant difference (p < 0.05). Only for IPS e.max ZirCAD was the Ra of the glazed surface significantly higher than the finished/polished surface (p < 0.0001). Significant variations in the surface roughness (Ra) were exhibited between the finished/polished and glazed surfaces of the five test materials. Hybrid ceramics showed the highest Ra values for the finished/polished surfaces, and zirconia exhibited the highest Ra values among the glazed surfaces among the tested materials. The Ra values of either finished/polished or glazed surfaces of the test materials were within the clinically acceptable range (0.2-0.5 µm), except for the glazed surface of the zirconia ceramics (0.84 µm).

8.
Int J Biol Macromol ; 254(Pt 3): 128097, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37972840

RESUMEN

The effect of 1.0 % (w/v) sodium alginate (SA) glazing on surface frost formation and the quality of frozen fish balls in repeated freeze-thaw (F-T) cycles was studied. The optimal glazing property of 1.0 % SA solution was manifested by high transmittance, excellent water resistance, and high ice glazing rate. After seven F-T cycles, compared with the control, the ice production, thawing loss, and total volatile base nitrogen (TVB-N) value of samples with 1.0 % ice glazing decreased by 28.30 %, 21.02 %, and 27.35 %, while the chewiness and whiteness were increased by 15.02 % and 10.40 %, respectively. Moreover, compared to the control, the microstructure of fish balls glazed with 1.0 % SA was smoother and more uniform, and the ice crystal diameter was smaller. Therefore, 1.0 % SA glazing effectively inhibits the formation of ice crystals, reducing water migration and loss while minimizing damage to the meat structure, thus enhancing the quality of meat products.


Asunto(s)
Hielo , Carne , Animales , Congelación , Carne/análisis , Agua , Productos Pesqueros/análisis
9.
J Prosthodont Res ; 68(2): 273-282, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37245959

RESUMEN

Purpose This study aimed to determine the surface glazing effect on the mechanical and biological properties of three-dimensional printed dental permanent resins.Methods Specimens were prepared using Formlabs, Graphy Tera Harz permanent, and NextDent C&B temporary crown resins. Specimens were divided into three groups: samples with untreated surfaces, glazed surfaces, and sand-glazed surfaces. The flexural strength, Vickers hardness, color stability, and surface roughness of the samples were analyzed to identify their mechanical properties. Their cell viability and protein adsorption were analyzed to identify their biological properties.Results The flexural strength and Vickers hardness of the samples with sand glazed and glazed surfaces were significantly increased. The color change was higher for surface untreated samples than that for the samples with sand-glazed and glazed surfaces. The surface roughness of the samples with sand-glazed and glazed surfaces was low. The samples with sand-glazed and glazed surfaces have low protein adsorption ability and high cell viability.Conclusions Surface glazing increased the mechanical strength, color stability, and cell compatibility, while reducing the Ra and protein adsorption of 3D-printed dental resins. Thus, a glazed surface exhibited a positive effect on the mechanical and biological properties of 3D-printed resins.


Asunto(s)
Impresión Tridimensional , Arena , Ensayo de Materiales , Propiedades de Superficie , Resinas Sintéticas , Materiales Dentales
10.
J Sci Food Agric ; 104(6): 3507-3516, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38145928

RESUMEN

BACKGROUND: This study was conducted to investigate the quality and shelf life of shrimps (Parapenaeus longirostris, Lucas 1846) glazed with biodegradable gelatin solutions combined with grape (Vitis vinifera L.) seed oil (GSO). Therefore, shrimps were divided into five groups and were glazed with distilled water (control), G (gelatin), G + 5% GSO (gelatin with 5% GSO), G + 10% GSO (gelatin with 10% GSO) and G + 15% GSO (gelatin with 15% GSO). Glazed shrimps were vacuum packaged and stored at -18 °C for 12 months. Proximate composition of the shrimps was determined, and the microbial (total viable counts, psychrotrophic bacteria count and Enterobacteriaceae), sensorial, chemical (residual sulfite, pH, total volatile basic nitrogen, trimethylamine nitrogen, thiobarbituric acid reactive substances) analysis, colour measurement, and melanosis formation were evaluated throughout the storage period. RESULTS: According to the analysis results, edible G + GSO coatings improved the meat quality and the brightness of the shrimps. The combined treatment reduced the quality loss of the shrimps which was caused by lipid content and prevented the total psychotropic bacteria growth throughout the storage. Moreover, glazing with G + GSO retarded the melanosis formation of the frozen shrimps. CONCLUSION: The study results revealed that GSO may be a recommended alternatively to sodium metabisulfite, which is a hazardous chemical substance commonly used against melanosis of shrimps. © 2023 Society of Chemical Industry.


Asunto(s)
Melanosis , Vitis , Animales , Gelatina/química , Crustáceos , Aceites de Plantas , Nitrógeno
11.
Environ Sci Technol ; 57(49): 20494-20500, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38008908

RESUMEN

Although the global ban on leaded gasoline has markedly reduced lead poisoning, many other environmental sources of lead exposure, such as paint, pipes, mines, and recycling sites remain. Existing methods to identify these sources are either costly or unreliable. We report here a new, sensitive, and inexpensive lead detection method that relies on the formation of a perovskite semiconductor. The method only requires spraying the material of interest with methylammonium bromide and observing whether photoluminesence occurs under UV light to indicate the presence of lead. The method detects as little as 1.0 ng/mm2 of lead by the naked eye and 50 pg/mm2 using a digital photo camera. We exposed more than 50 different materials to our reagent and found no false negatives or false positives. The method readily detects lead in soil, paint, glazing, cables, glass, plastics, and dust and could be widely used for testing the environment and preventing lead poisoning.


Asunto(s)
Exposición a Riesgos Ambientales , Intoxicación por Plomo , Humanos , Compuestos de Calcio , Óxidos , Intoxicación por Plomo/prevención & control , Pintura , Polvo
12.
J Prosthodont ; 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37947149

RESUMEN

PURPOSE: To evaluate the effects of 1 versus 2 glaze firings on the color and mechanical properties of an extrinsically characterized lithium disilicate ceramic after thermal cycling, brushing, or both. MATERIALS AND METHODS: Eighty specimens were divided into 2 groups: 1 glaze firing (GL1) and 2 glaze firings (GL2). Each group was subdivided into 4 groups (n = 10), according to the experimental conditions: thermal-cycling, brushing, thermal-cycling + brushing, and immersion in distilled water (control). Color variation, surface roughness, and Vickers microhardness were analyzed before each designated experiment and after the simulated periods of 2.5, 5, and 10 years. Three-way mixed ANOVA was used for all outcomes, followed by 1-way ANOVA, repeated measures 1-way ANOVA, Bonferroni post hoc test, and t-test to check for statistical differences (α = 0.05). RESULTS: Thermal cycling generated greater color changes in the GL1 group at 2.5 and 5 years (p < 0.001; p = 0.013). Brushing generated color changes in GL1 at 5 years (p = 0.003) and in GL2 at 10 years (p = 0.017). Regarding surface roughness, the GL1 group suffered alterations in thermal cycling + brushing at 5 years. In the control group, the GL1 group exhibited higher roughness values than GL2 (p < 0.05). Most of the groups experienced an increase in microhardness at 2.5 years (p < 0.05). In the GL1 group, thermal-cycling increased the microhardness at 5 years (p = 0.006); at 5 and 10 years, the GL1 group had a higher microhardness than the GL2 in thermal-cycling + brushing (p < 0.05). CONCLUSION: Ceramics with 1 glaze firing showed greater color, roughness, and microhardness changes compared to those submitted to 2 firings.

13.
Heliyon ; 9(10): e20436, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37790978

RESUMEN

Modern humans spend more time indoors than their ancestors. In indoor environments, windows are the primary building elements that provide access to daylight and views. The advancement of the building industry has introduced new glazing and coating technologies for windows. Electrochromic glazing, in particular, has gained popularity in recent decades. These glazings' tint varies with light exposure and electrical voltage, affecting the spectral power distribution of transmitted daylight. The growing knowledge of the impacts of light on sleep and health encourages an evaluation of the non-visual effects of daylight transmitted through glazing. Therefore, the aim of this paper is to investigate the non-visual effects of transmitted daylight through one clear and one smart glazing and evaluate the colour appearance variations. However, conventional visualisation tools are inadequate for this purpose, necessitating the use of alternative techniques that consider the spectral power distribution of light. To accomplish this, the Radiance-based Lark spectral lighting simulation tool was utilised. The non-visual effects were analysed by examining the responses of the five photoreceptors (Short-, Medium-, Long-wavelength cones, Rods, and ipRGCs) to light using the CIE spectral sensitivity functions. Additionally, the changes in colour appearance were assessed using six attributes: lightness, hue, chroma, vividness, depth, and clarity. The results demonstrate the effect of the studied glazing on non-visual light stimulation and colour appearance while presenting the challenges, applicability, and limitations of spectral simulation techniques. The proposed method yields promising results and can be a valuable tool for evaluating the effects of glazing on humans.

14.
Materials (Basel) ; 16(14)2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37512328

RESUMEN

The VIG (Vacuum Insulated Glazing) unit, composite glazing in which the space between glass panes is filled with vacuum, is one of the most advanced technologies. The key elements of the construction of VIG plates are the support pillars. Therefore, an important issue is the analysis of their mechanical properties, such as Young's modulus and their variability over a long period of time. Machine learning (ML) methods are undergoing tremendous development these days. Among the many different techniques included in AI, neural networks (NN) and extreme gradient boosting (XGB) algorithms deserve special attention. In this study, to train selected methods of machine learning, numerical data developed in the VIG plate modelling process using Abaqus program were used. The test method proposed in this article is based on the VIG plate subjected to forced vibrations of specific frequencies and then the reading of the dynamic response of the composite plate. Such collected and pre-developed experimental data were used to obtain the mechanical parameters of the steel elements located inside the analysed vacuum glazing. In the future, the proposed research methods can be used to analyse the mechanical properties of other types of composite panels.

15.
Heliyon ; 9(4): e15183, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37151628

RESUMEN

Metal - aluminium windows have an important position in residential architecture. High thermal conductivity, as the main material disadvantage of aluminium, is solved by decoupling the thermal bridge. With the improved geometry of the frames and the appropriate break of the thermal bridge, high-performance systems are achieved, used for all-glazed facades of various building categories around the world. Mathematical modelling methods enable highly accurate prediction of the system's behaviour, thereby achieving shape and material optimization of the frame and glazing concept. Despite this, there are products on the market that show defects of a thermal technical nature, which is caused, among other things, by the absence of a standard requirement for the minimum surface temperature of the window in some countries (e.g. the Czech Republic). The subject of the study is condensation on the surface of the glazing bead of aluminium lift-and-slide windows in a residential complex in eastern Slovakia. The occurrence of condensation is conditioned by operating boundary conditions - air temperature, relative air humidity, heating and ventilation mode. Through experimental measurements and subsequent modelling, the cause of the structural failure was determined, alternative solutions were proposed, and the optimal solution for adjusting the glazing bead was selected. The modelling methodology used is derived for use in determining condensation risk. With external boundary conditions from Typical Meteorological Year - ASHRAE 2.0 (TMY) for the Presov (SK) location, the annual decrease in the amount of condensation and condensation time after the adjustment of the glazing bead compared to the original construction was determined.

16.
Eur J Prosthodont Restor Dent ; 31(4): 321-331, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37194583

RESUMEN

INTRODUCTION AND OBJECTIVES: CAD/CAM prostheses may be produced in prosthetic laboratories or directly by practitioners. Quality of ceramic polishing procedures is a controversial topic and it would be interesting for practitioners working with CAD/CAM devices to determine which method is the most efficient regarding finishing and polishing. This systematic review aims to evaluate the impact of different finishing and polishing procedures on the surface of milled ceramics. MATERIALS AND METHODS: A precise request was launched on the PubMed database. Studies included if they met the criteria of a specifically prepared PICO search. A first selection was performed by analysing titles and abstracts: the articles presenting a study conducted on non-CAD/CAM milled ceramics and research not containing comparisons of finishing procedures were not included. Roughness was evaluated in 15 articles. Nine papers recommended mechanical polishing over glazing regardless of the type of ceramic used. However, no significant differences were detected between the surface roughness of glazed and polished ceramics in nine other publications. CONCLUSIONS: there is no scientific evidence demonstrating the superiority of hand polishing over glazing on CAD/CAM-milled ceramics.


Asunto(s)
Pulido Dental , Porcelana Dental , Ensayo de Materiales , Pulido Dental/métodos , Propiedades de Superficie , Cerámica , Diseño Asistido por Computadora
17.
ACS Appl Mater Interfaces ; 15(3): 4267-4274, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36630212

RESUMEN

Dynamic windows allow monitoring of in-door solar radiation and thus improve user comfort and energy efficiency in buildings and vehicles. Existing technologies are, however, hampered by limitations in switching speed, energy efficiency, user control, or production costs. Here, we introduce a new concept for self-powered switchable glazing that combines a nematic liquid crystal, as an electro-optic active layer, with an organic photovoltaic material. The latter aligns the liquid crystal molecules and generates, under illumination, an electric field that changes the molecular orientation and thereby the device transmittance in the visible and near-infrared region. Small-area devices can be switched from clear to dark in hundreds of milliseconds without an external power supply. The drop in transmittance can be adjusted using a variable resistor and is shown to be reversible and stable for more than 5 h. First solution-processed large-area (15 cm2) devices are presented, and prospects for smart window applications are discussed.

18.
Foods ; 13(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38201148

RESUMEN

Sake (Japanese rice wine) was fermented in pottery for more than a millennium before wooden barrels were adopted to obtain a greater brewing capacity. Although a recently conducted analysis of sake brewed in pottery indicated that sake brewed in unglazed pottery contains more ethanol than that brewed in glazed pottery, little is known about the characteristics of sake brewed in pottery. In this study, we used two types of ceramic containers of identical size, one glazed and one unglazed, for small-scale sake brewing to evaluate the effects of glazing on fermentation properties. The following parameters were measured continuously in the sake samples over 3 weeks of fermentation: temperature, weight, ethanol concentration, and glucose concentration in sake mash. Taste-sensory values, minerals, and volatile components were also quantified in the final fermented sake mash. The results show that, in the unglazed containers, the temperature of the sake mash was lower and the weight loss was higher compared to the sake mash in the glazed containers. The quantity of ethanol and the levels of Na+, Fe3+, and Al3+ tended to be higher in the sake brewed in the unglazed pottery. A taste-sensory analysis revealed that umami and saltiness were also higher in the samples brewed in the unglazed pottery. These results suggest that glazing affects multiple fermentation parameters and the flavor of sake brewed in pottery. They may also suggest that the materials of the containers used in sake brewing generally affect the fermentation properties.

19.
J Int Soc Prev Community Dent ; 12(5): 540-546, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532324

RESUMEN

Aims and Objectives: This study evaluated the surface roughness of three dental ceramics after polishing with three types of extraoral ceramic polishing sets. Materials and Methods: One hundred and twenty specimens were fabricated from feldspathic porcelain, lithium disilicate, and zirconia ceramics. The specimens were randomly allocated into four subgroups (n = 10). Group one was glazed (control) and the other three groups were ground using fine diamond burs and then sequentially polished by two rubber wheels from three polishing sets: feldspathic porcelain, lithium disilicate, and zirconia sets. The surface roughness measurement was performed with a profilometer and the surfaces were analyzed using scanning electron microscopy. Elemental compositions of three polishing sets were examined using x-ray powder diffraction. The surface roughness values of three polishing systems were compared by one-way analysis of variance with Dunnett's T3 post hoc test. The significance level was set at p < 0.05. Results: There was no significant difference in surface roughness when polishing ceramics with the lithium disilicate and zirconia polishing sets. In addition, those two sets provided lower roughness compared with the feldspathic porcelain polishing set and glazing. The main component of all polishing wheels was carbon, and only zirconia polishing wheel had more additional trace elements, which were titanium and silica. Conclusion: Lithium disilicate and zirconia extraoral polishing sets achieved superior results compared to feldspathic polishing set and glazing.

20.
Materials (Basel) ; 15(24)2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36556874

RESUMEN

Human history is largely characterized by the massive use of wood, the most well-known natural composite material, possessing unique thermal, mechanical, and environmental features that make it suitable for several applications, ranging from civil engineering, art, and household uses, to business uses (including furniture, stationery, shipbuilding, and fuel). Further, as a renewable and recyclable biomass, wood perfectly matches the current circular economy concept. However, because of its structure and composition, wood is not transparent: therefore, the possibility of removing the embedded lignin, hence limiting the light-scattering phenomena, has been investigated over the last ten to fifteen years, hence obtaining the so-called "transparent wood (TW)". This latter represents an up-to-date key material, as it can be utilized as obtained or further functionalized, combining the transparency with other features (such as flame retardance, energy storage ability, and environmental protection, among others), which widen the potential (and practical) applications of wood. The present manuscript aims at summarizing first the current methods employed for obtaining transparent wood, and then the latest achievements concerning the properties of transparent wood, providing the reader with some perspectives about its novel functionalizations and applications.

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