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This article explores the technological processes involved in the production of the Amarna tablets, focusing on firing temperatures associated with these cuneiform artefacts. Building on the extensive research conducted by Goren, Finkelstein and Naʾaman (2004), it examines the interplay of geographical origins, individual scribes and firing practices, offering insights into the manufacturing processes. Through several case studies, such as the Babylonian and Rib-Hadda's Byblos letters, it demonstrates how firing temperatures were influenced by geographical and/or historical context, with Byblos scribes adapting to local practices. This study underscores the significance of firing in the production of cuneiform production, shedding light upon ancient cuneiform manufacturing methods and scribal traditions. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is a multifunctional material with a myriad of potential applications, from high-power electronics to friction applications to power generation. Grafting preceramic polymers (PCPs) from SiC nanoparticles would create a platform for forming SiC via a polymer derived route that would have advantages over simple particle-PCP slurries and may enable new additive manufacturing inks or spreadable coatings with controlled rheology. Grafting PCPs directly on SiC powders would greatly improve dispersion of these particles and yield a single component system. Moreover, PCP-grafted-SiC would be a new addition to the burgeoning field of polymer grafted nanoparticles (PGNPs). Herein, SiC nanoparticles were surface-modified in a grafting-from polymerization reaction to create polycarbosilane (PCS) grafted SiC. Surface grafting was verified through a number of analytical techniques and the synthesized materials were pyrolyzed at 1600 °C. The PCS-grafted SiC retained 66 % of its pre-pyrolysis mass, representing a significant improvement over PCS-grafted silica nanoparticles from our previous work (20 wt% yield). In addition to an increased ceramic yield, the grafting of PCS to SiC also resulted in the formation of a SiC phase not present in the simple physical mixture of SiC nanopowder in PCS. This study demonstrated that PCP-grafted nanoparticles (GNPs) can be synthesized utilizing non-oxide nanoparticle cores with desirable rheology, opening possibilities for future ceramic inks and coatings. [ABSTRACT FROM AUTHOR]

The possibility of isovalent substitution of zinc and cobalt atoms in the structure of willemite Zn2SiO4 was studied. Ceramic pigments with a willemite structure of blue, violet, and light blue colors were synthesized. Samples of blue color were used in the manufacture of glazes. During the synthesis of the pigments, synthetic silicon oxide was replaced by natural quartz sand. The pigments were synthesized by solid-state method at a temperature of 1270°C. The physical and chemical properties of the synthesized blue pigment were determined. In addition, the pigment was tested for use in traditional glazes for the coloring of ceramic products. It was established that the obtained blue pigment provides high aesthetic and decorative characteristics at a relatively low price. [ABSTRACT FROM AUTHOR]

Accurately measuring water holdup in horizontal wells is crucial for effectively using heavy oil reservoirs. The capacitance method is among the most widely used and accurate techniques. However, the absence of suitable insulating materials at high temperatures and pressures limits the effectiveness of capacitive water holdup measurement in heavy oil thermal recovery. This study introduces a new composite material based on an aviation-grade, special glass glaze as the insulating medium doped with inorganic components (CaSO4, MgSO4, Ca(OH)2, and SiO2). This new composite material demonstrates outstanding insulating performance under high-temperature and high-pressure conditions in water. A water environment with a high temperature of 350 °C and a pressure of 12 MPa considerably enhances the composite material's insulation. After 72 h of continuous use, the insulation performance remains 0.3 MΩ. The layers exhibit improved insulation and stability, maintaining integrity through five consecutive temperature shocks in 500 °C air and 20 °C water. XRD, IR, SEM, and TEM analyses reveal that the new composite material is amorphous after firing and that the addition of inorganic components improves the bonding between the glass glaze components and contributes to a denser structure. Simultaneously, SEM and TEM analyses indicate that adding inorganic components results in a smoother, crack-free, and more compact surface of the special glass glaze. This enhancement is crucial for the material's long-term stability in high-temperature and high-pressure water environments. [ABSTRACT FROM AUTHOR]

In a future energy system prospective, predictably dominated by (often) remote and (always) unsteady, nondispatchable renewable power generation from solar and wind resources, hydrogen (H2) and ammonia (NH3) have emerged as logistically convenient, chemically simple and carbon-free chemicals for energy transport and storage. Moreover, the reliability of supply of a specific fuel feedstock will remain unpredictable in the upcoming energy transition period. Therefore, the ability of gas turbine combustion systems to seamlessly switch between very disparate types of fuels must be ensured, aiming at intrinsically fuel-flexible combustion systems, i.e., capable of operating cleanly and efficiently with novel carbon-free energy vectors like H2 and NH3 as well as conventional fossil fuels, e.g., natural gas or fuel oils (back-up feedstock). In this context, a convenient feature of Ansaldo's constant pressure sequential combustion (CPSC) system, resulting in a fundamental advantage compared to alternative approaches, is the possibility of controlling the amount of fuel independently fed to the two combustion stages, depending on the fuel reactivity and combustion characteristics. The fuel-staging strategy implemented in the CPSC system, due to the intrinsic characteristics of the auto-ignition stabilized reheat flame, has already been proven able of handling fuels with large hydrogen fractions without significant penalties in efficiency and emissions of pollutants. However, ammonia combustion is governed by widely different thermo-chemical processes compared to hydrogen, requiring a considerably different approach to mitigate crucial issues with extremely low flame reactivity (blow-out) and formation of significant amounts of undesired pollutants and greenhouse gases (NOx and NO2). In this work, we present a fuel-flexible operational concept for the CPSC system and, based on unsteady Reynolds-Averaged Navier-Stokes (uRANS) and large eddy simulation (LES) performed in conjunction with detailed chemical kinetics, we explore for the first time full-load operation of the CPSC architecture in a Rich-Quench-Lean (RQL) strategy applied to combustion of partially-decomposed ammonia. Results from the numerical simulations confirm the main features of ammonia-firing in RQL operation already observed from previous work on different combustion systems and suggests that the CPSC architecture has excellent potential to operate in RQL-mode with low NOx and NO2 emissions and good combustion efficiency. [ABSTRACT FROM AUTHOR]

Abstract The thermal conductivity of engobed building ceramics was studied as a function of their microstructure. The following thermal conductivity coefficients of the samples were determined: clinker bricks with 5% water absorption - 1.04 W/(m·K) and facing bricks (ordinary) with 12% water absorption - 0.48 W/(m·K) (ignoring the voids in the samples). A comparison of the thermal conductivity of brick samples of uniform thickness without engobe and with engobe showed that the latter had a slight increase in thermal conductivity of 0.3% due to forming a denser outer layer on its surface with 2.0-0.3% water absorption. However, as the engobe coating is applied as an additional layer on the top of the ceramic bricks and the product has a greater thickness, the heat flow through the engobed bricks is 0.1-0.2 % lower. The results can be applied to technologies for achieving energy-efficient decorative and protective coatings for building ceramics.

This study investigates the reliability of commonly utilized digital spiking neurons and the potential side-channel vulnerabilities in neuromorphic systems that employ them. Through our experiments, we have successfully decoded the parametric information of Izhikevich and leaky integrate-and-fire (LIF) neuron-based spiking neural networks (SNNs) using differential power analysis. Furthermore, we have demonstrated the practical application of extracted information from the 92% accurate pretrained standard spiking convolution neural network classifier on the FashionMNIST dataset. These findings highlight the potential dangers of utilizing internal information for side-channel and denial-of-service attacks, even when using the usual input as the attack vector. [ABSTRACT FROM AUTHOR]

This work evaluates the impacts of the addition of cellulose fibres (5 and 10 wt%) and pumice powder (5 wt%) as pore forming agents on the porosity, microstructure and mechanical strength of two traditional ceramic compositions: stoneware and terracotta. Open and closed porosities, pore size distribution and morphology were obtained from the combined use of the Archimedes method, mercury intrusion porosimetry and SEM image analyses. The results show an increase in the open porosity ratio in the case of cellulose fibre addition, whereas pumice powder addition promotes an increase in the closed porosity. The addition of cellulose also modifies the pore morphology of stoneware samples and induces a pore size increase. The decrease in mechanical strength caused by a lower firing temperature is greater than the decrease linked to the porosity generated by pore-forming agent addition. As the moduli of rupture of the produced porous tiles are higher than those needed by the standards, this work proposes new opportunities for lightning ceramic products. [ABSTRACT FROM AUTHOR]

Purpose: This article seeks to enhance the understanding as to why head coaches and general managers (GMs) in the National Basketball Association (NBA) and the National Football League (NFL) exit from their positions. Design/methodology/approach: Three hypotheses were investigated using a series of quantitative and qualitative data from the past 30 years. The samples analyzed are comprised of 891 GM and coach annual observations for the NBA clubs and 949 GM and coach observations for the NFL clubs. Analyses include a logit analysis for coach exit/retention, a logit analysis for GM exit/retention and textual analysis via topic modeling via latent Dirichlet allocation. Findings: Results show a correlation between a coach exiting and a GM exiting simultaneously, thus amplifying the importance of these two roles in enhancing or destroying the success of a club and supporting the need for a deeper understanding of both roles, particularly the GM. The results further highlight cultural differences across clubs in terms of GM and coach turnover, a factor that often is heavily influenced by club ownership. Originality/value: The results support the role of owners in exits, confirm the importance of winning in avoiding an exit, find a high level of interrelationship between GM and coach exits and show that past culture of firings influences future exit decisions. [ABSTRACT FROM AUTHOR]

Copyright of Motif Academy Journal of Folklore is the property of Motif Yayincilik 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.)

Accurately measuring water holdup in horizontal wells is crucial for effectively using heavy oil reservoirs. The capacitance method is among the most widely used and accurate techniques. However, the absence of suitable insulating materials at high temperatures and pressures limits the effectiveness of capacitive water holdup measurement in heavy oil thermal recovery. This study introduces a new composite material based on an aviation-grade, special glass glaze as the insulating medium doped with inorganic components (CaSO4, MgSO4, Ca(OH)2, and SiO2). This new composite material demonstrates outstanding insulating performance under high-temperature and high-pressure conditions in water. A water environment with a high temperature of 350 °C and a pressure of 12 MPa considerably enhances the composite material’s insulation. After 72 h of continuous use, the insulation performance remains 0.3 MΩ. The layers exhibit improved insulation and stability, maintaining integrity through five consecutive temperature shocks in 500 °C air and 20 °C water. XRD, IR, SEM, and TEM analyses reveal that the new composite material is amorphous after firing and that the addition of inorganic components improves the bonding between the glass glaze components and contributes to a denser structure. Simultaneously, SEM and TEM analyses indicate that adding inorganic components results in a smoother, crack-free, and more compact surface of the special glass glaze. This enhancement is crucial for the material’s long-term stability in high-temperature and high-pressure water environments.

This paper begins with an introduction to porcelain tiles. A review of the major scientific and technological features of mullite-based porcelain tiles (MPTs) and anorthite-based porcelain tiles (APTs), focusing primarily on the raw material, processing, phase evolution and mechanical behavior, is then presented. Based on the porcelain tile firing behavior and a series of physical and chemical changes that can occur, a comprehensive comparison is described. In the last part, the prospects for further developments related to MPTs and APTs are discussed.

Prostaglandin E2 (PGE2) is an inflammatory mediator synthesized by the brain constitutive cyclooxygenase enzyme. PGE2 binds to G protein-coupled EP1-4 receptors (EP1 to Gq, EP2,4 to Gs, and EP3 to Gi/o). EP2, EP3 and EP4 receptors are expressed in the locus coeruleus (LC), the main noradrenergic nucleus in the brain. EP3 receptors have been explored in the central nervous system, although its role regulating the locus coeruleus neuron activity has not been pharmacologically defined. Our aim was to characterize the function of EP3 receptors in neurons of the LC. Thus, we studied the effect of EP3 receptor agonists on the firing activity of LC cells in rat brain slices by single-unit extracellular electrophysiological techniques. The EP3 receptor agonist sulprostone (0.15 nM–1.28 µM), PGE2 (0.31 nM–10.2 µM) and the PGE1 analogue misoprostol (0.31 nM–2.56 µM) inhibited the firing rate of LC neurons in a concentration-dependent manner (EC50 = 15 nM, 110 nM, and 51 nM, respectively). The EP3 receptor antagonist L-798,106 (3–10 µM), but not the EP2 (PF-04418948, 3–10 µM) or EP4 (L-161,982, 3–10 µM) receptor antagonists, caused rightward shifts in the concentration-effect curves for the EP3 receptor agonists. Sulprostone-induced effect was attenuated by the Gi/o protein blocker pertussis toxin (pertussis toxin, 500 ng ml-1) and the inhibitors of inwardly rectifying potassium channels (GIRK) BaCl2 (300 µM) and SCH-23390 (15 µM). In conclusion, LC neuron firing activity is regulated by EP3 receptors, presumably by an inhibitory Gi/o protein- and GIRK-mediated mechanism. [ABSTRACT FROM AUTHOR]

In order to assess the feasibility of utilizing soapstone waste, which is generated during the production of stone blocks for fireplaces and other energy-saving devices, the effect of its addition to clay on the technological and thermal properties of ceramic materials was investigated. Two local clays and soapstone processing waste were characterized using XRD, SEM-EDS, XRF, DTA-TG, and granulometric analysis. The linear firing shrinkage, water absorption, density, flexural strength, thermal conductivity, specific heat capacity, and thermal shock resistance of the fired ceramic samples were analyzed. The results have shown that addition of soapstone waste to clay in an amount of 40 wt.% increases flexural strength, enhances thermal stability, and, additionally, reduces the thermal conductivity of the experimental samples. The technological properties of the final product meet the standard requirements for ceramic tiles. [ABSTRACT FROM AUTHOR]

The worse situation in the global economy due to the COVID-19 pandemic disease and the Russia–Ukraine war caused problems in the supply of raw materials such as Ukrainian clay, which is at the top of the global demand, and brought the Turkish ceramics industry to the brink of a severe crisis. For this reason, ceramic manufacturers in Turkey have sought alternative raw materials and additives to meet especially the needs of the domestic market. This research aimed to evaluate natural stone-cutting wastes as a functional additive in industrial ceramic tile production. For this purpose, a part of illitic clay (IC) in the floor tile formulation was replaced with tuff waste (TW) in varying amounts (up to 18 wt.%). The floor tile compositions prepared with different percentages of TW substitution were pressed uniaxially at 200 kg/cm2, and the green ceramic bodies were then fired at 1186 °C for 46 min in an industrial roller kiln. The development of the microstructure was followed by XRD and SEM analysis. The technological properties (linear shrinkage, water absorption, green, and fired strength) were investigated as a function of the waste addition. The results revealed that the gradual substitution of clay with tuff waste accelerated liquid-phase formation and, thus, sintering progress, resulting in denser microstructure. The technological properties were found to be influenced by the waste addition. The replacement of IC with TW produced a noticeable change in the quality of the floor tiles, contributing to an increase of up to 24% and 46% in the green and fired strength, respectively. It was also found that replacing the clay in the industrial tile composition with 7 wt.% tuff waste allowed the production of enhanced floor tiles having the highest green (1.55 MPa) and fired (27.3 MPa) strength and the lowest water absorption value (0.51%). [ABSTRACT FROM AUTHOR]

The quality of iron ore pellets significantly affects the efficiency of pig iron and HBI production. The purpose of the work is to assess the potential for increasing the strength of iron ore pellets based on their macrostructure control. As a result of the study, it is found that the compressive strength of the pellets decreases monotonically at 20 daN/pel for each percentage of porosity. The external manifestations of structural defects (small crack, large crack, pellet fragments, pellet adhesions) are studied. It is revealed that the bulk of industrial pellets have optically detectable structural defects. At the same time, there is a lower content of fractured pellets and a higher proportion of aggregations in samples from a rich in iron concentrate. The crack orientation also depends on the degree of concentrate enrichment: in pellets with a higher iron content, the cracks are predominantly concentric, and with a decrease in the mass fraction of iron in the pellets, radial cracks predominate. Controlling the macrostructure parameters and the pellet strength is possible by forming a given porosity by adding fluxes and using polymer binders, minimizing the number and height of raw pellet overloads, obtaining dense row pellets with minimal porosity, organization of heat treatment of pellets with limited conditions for the defect formation—drying and firing rate, uniform thermal field across the width and height of the layer; cooling rate. [ABSTRACT FROM AUTHOR]

This study provides a characterization of materials from wastes and outcrops of two inactive bauxite mines located close to Sant Joan de Mediona and Peramola, Spain. Mineralogy was determined via powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Thermal properties were measured via differential thermal analysis–thermogravimetry (DTA-TG) and gresification tests. The crystalline phases are medium-high crystalline kaolinite and variable amounts of illite, quartz, calcite, boehmite, hematite and rutile/anatase. DTA show two endothermic peaks produced by the dehydroxylation of minerals: the first peak, at 530–538 °C, belongs to boehmite; the second peak, at 535–568 °C, corresponds to kaolinite. An exothermic peak at 950–978 °C is associated with mullite crystallization. The optimal sintering temperatures obtained from the gresification curves (firing shrinkage and water absorption) were 970 °C for carbonate-poor, illite-rich clays; 1100 °C for illite- and carbonate-poor samples; and near 1190 °C for carbonate-rich materials. The carbonate-poor samples fired at 1300 °C contain sillimanite and mullite, and the carbonate-rich materials are rich in gehlenite, anorthite, and hedenbergite. The mineralogy of these materials is sufficient to obtain ceramic materials with suitable properties, but not their low plasticity. They could be used in the formulation of bricks or as part of mixtures to produce refractory ceramics. [ABSTRACT FROM AUTHOR]

This study explores the possibility of using stone processing sludge in ceramic building materials. In this research, fatty clays were selected from quarries and sludge from stone processing plants. These materials were not further modified. The clay and sludge were dried in a drying cabinet for 24 hours at a temperature of 105±2 ºC. The samples were fired at a temperature of 950 degrees Celsius. The shrinkage of the samples and the weight loss of the samples due to the sludge content after firing were analyzed. It was found that the sludge has a density similar to clay, allowing it to be mixed without adjusting proportions. The plasticity index of the sludge was lower than that of clay, despite the similarity in particle size of these materials. The chemical analysis of the sludge and clay showed a carbon percentage. X-ray fluorescence of the sludge and clay indicated their similarity without contamination by heavy metals or chemical elements. It was also determined that the linear shrinkage of ceramic samples increases with increasing sludge content. Based on this, it can be concluded that granite sludge can be incorporated into ceramic materials for brick production.

This study focused on mullite-based and forsterite-based ceramic bricks fired at 1000 °C from mixtures of fly ash (40 mass%) and kaolins or vermiculites (60 mass%). The structural, physical, and mechanical properties were characterized by X-ray powder diffraction, nitrogen physisorption, mercury porosimetry, thermogravimetry, and compressive strength. In the development of green-material-derived photocatalysts, we evaluated fly ash ceramic bricks based on kaolins and vermiculites, which deserve deeper research. Alkali potassium in the mixtures positively influenced the reduction of the firing temperature, shrinkage, small porosity, and high compressive strength of ceramic bricks. The crystallization of mullite in fly ash was observed on exotherm maxima from 813 to 1025 °C. Muscovite/illite admixture in kaolins precursor of mullite-based ceramics reduced the crystallization temperature of mullite by up to 70 °C. Vermiculite–hydrobiotite–phlogopite in mixed layers of a raw vermiculite precursor of forsterite-based ceramics controlled the formation of enstatite and forsterite in the temperature range from 736 ± 6 °C to 827 ± 6 °C. Mullite- and forsterite-based ceramic bricks were also investigated for photocatalytic hydrogen production. The photocatalytic generation of hydrogen in the presence of mullite-based ceramic bricks was positively correlated with the percentages of Fe2O3 in the lattice of mullites and in the presence of forsterite-based ceramics with the presence of diopside. Mullite-based ceramic produced the highest yield of hydrogen (320 µmol/gcat after 4 h of irradiation) in the presence of mullite with the highest 10.4% substitution of Fe2O3 in the lattice. The forsterite-based ceramic produced the highest hydrogen yields (354 µmol/gcat after 4 h of irradiation) over more active diopside than forsterite. [ABSTRACT FROM AUTHOR]

In the present study, the effect of MgO in the form of olivine flux on low- and high-alumina iron ore pellet mineralogy and pellet quality was studied. Green pellets were prepared by varying the MgO content from 0 to 1.5% with a basicity (CaO/SiO2) of 0.30. The pellets were tested for green pellet properties, cold crushing strength (CCS), and reduction degradation index (RDI) and fired at temperatures between 1300 and 1320 oC. An optical microscope with an image analyzer, SEM-EDS, was used to assess the mineralogical phases present in the pellets and the chemical analysis of the mineralogical phases, respectively. The laboratory tests showed that with increasing MgO addition in both low and high alumina pellets, magnesio-ferrite & silicate melt phases increased and the porosity and hematite phases decreased. The decrease in porosity was due to increase in silicate melt formation from the silica in the olivine. With increasing MgO addition, the CCS value of the pellets increased up to an MgO content of 0.9 to 1.1%. Thereafter, the CCS value of the pellets decreased with increasing MgO addition for both low and high alumina pellets. At an MgO content of 0.9 to 1.1%, the CCS value was higher due to the formation of a low melting point magnesio-ferrite phase, which imparted strength to the pellets. For pellets with an MgO level of >1.1, the RDI was within the control limit for both low- and high-alumina pellets. This may be due to a reduction in the porosity of the pellet and a better distribution of the silicate melt phase. Low-alumina pellets showed better physical and metallurgical properties compared to high-alumina iron ore pellets. [ABSTRACT FROM AUTHOR]

This paper begins with an introduction to porcelain tiles. A review of the major scientific and technological features of mullite-based porcelain tiles (MPTs) and anorthite-based porcelain tiles (APTs), focusing primarily on the raw material, processing, phase evolution and mechanical behavior, is then presented. Based on the porcelain tile firing behavior and a series of physical and chemical changes that can occur, a comprehensive comparison is described. In the last part, the prospects for further developments related to MPTs and APTs are discussed. [ABSTRACT FROM AUTHOR]

This study investigated a novel method for artificial synthesis of β-tricalcium phosphate (β-TCP). The binder of the phosphate-bonded investment was replaced with calcium oxide instead of magnesium oxide and sintered in an electric furnace. The water/powder mixing ratio for hardening was determined using preliminary experiments. Thermal analysis was performed to check the thermal behavior of the sample tested. In addition, the fired sample was analyzed using an X-ray diffraction apparatus to identify the compounds after sintering. The hardened sample exhibited multiple compounds, including unreacted components, post which, new compounds were generated by heating. Peaks of calcium pyrophosphate and β-TCP were confirmed at 800ºC and 1,300ºC, respectively. β-TCP could be easily synthesized within the limited study by sintering at 1,300ºC both monoammonium phosphate and calcium oxide. Experimental results suggest that β-TCP can be easily synthesized by simulating the conventional dental casting process. [ABSTRACT FROM AUTHOR]

In this paper, based on integer-order Hindmarsh–Rose (HR) neurons under an electric field, the fractional-order model is constructed, and the nonlinear term is decomposed by the Adomian decomposition method, and the numerical solution of the system is obtained. The firing behavior of the neuron model is analyzed by using a phase diagram, interspike interval (ISI) bifurcation diagram, sample entropy (SE) complexity, and largest Lyapunov exponent (LLE). Based on the sliding mode control theory, a chaos synchronization controller of the system is designed. Matlab simulation results show that the controller is realizable and effective, and also has the characteristic of fast response, which provides a reference for the control and application of a memristor neural network system. [ABSTRACT FROM AUTHOR]

The heterogeneous coupled network has shown its research values in brain science and bionics. In this paper, a novel small heterogeneous coupled network through a memristive synapse is proposed and investigated. The model is constructed by coupling a 2D Hindmarsh–Rose (HR) neuron with a 3D Hopfield neural network (HNN) through a memristive synapse. Subsequently, the complex dynamical behaviors exhibited by the network were investigated. Specifically, we varied the coupling parameter k12 of the 3D HNN and found that the membrane potentials of the 2D HR neuron possess seven stable firing patterns. Then, by varying the coupling parameter k1 between the 2D HR neuron and the 3D HNN, the membrane potentials of the 2D HR neuron generated five stable firing patterns. Furthermore, by fixing the coupling parameters and varying the initial values of the network, multistability behavior was exhibited by the network. These findings have potential applications in brain science and bionics. Finally, a circuit is designed to realize the network in both simulation and experiments. [ABSTRACT FROM AUTHOR]

The design of porcelain stoneware tile composition is a very complex and time-consuming task, in the industry. After the long way to accomplish the product, processing, and cost requirements, the microstructure is seldom analyzed. If it is checked, it is not adjusted. The raw materials' chemical composition is one of the most helpful information to design. However, it has certain limitations because the mineralogy information is hidden. The paper approach formulates and optimizes porcelain stoneware compositions regarding raw materials' microstructure and mineralogy. Meta-analysis was applied to build models for mullite formation, firing temperature, and pyroplastic deformation. Kaolinite, illite/muscovite, talc, quartz, and feldspar were used as regressors. The robust microstructure is formed with interconnected mullite crystals. This feature could be numerically correlated to the mullite content ranging from 14% to 17%. Optimization was performed with mullite constrained from 13.5% to 17.5%, firing temperature <1230 °C and pyroplastic deformation <4.8x10−5 cm−1. It was possible to find feasible compositions' intervals. For instance, kaolinite needs to be between 23% and 37%. The comparison with 34 industrial compositions found that 90% of them have kaolinite content below the robust interval. This means it has opportunities to improve product and process performance in terms of stability, quality, cost, productivity, waste material incorporation, and sustainability. [ABSTRACT FROM AUTHOR]

Raw materials significantly determine the final composition and properties of a fired ceramic. Raman analysis which characterizes micro- and nanostructures of (coloured) glazes, opacified or not, was applied to shards mostly collected before the 1960s, currently at the Louvre Museum, originated in Anatolia, the Caucasus, Iran and Central Asia, which are, for most of them, characterized by the use of black lines to separate coloured areas, and dated to the period between the 12th and 19th centuries. Measurements were carried out in the laboratory with a blue laser excitation and/or on the conservation site with a mobile device (green laser). Three types of glazes were identified by their nanostructure of the silicate network: (i) a lead-rich glaze analogous to that of Byzantine, Zirid to Hafsid and al-Andalus productions, (ii) a lead-alkali glaze typical of the Ottoman productions of Iznik-Kütahya, and (iii) a mixed (poor lead/lead-free)-alkali glaze typical of Safavid productions. The colour determines the precise composition of the glaze. The identification is not only based on the signature of the stretching mode of the SiO4 tetrahedron (position of the wavenumber of the component(s)) but also on the position and shape of the continuous luminescence of the Raman background, characteristic of the raw materials used. Lead-tin yellow, Fe-rich, Mn-rich and Cr-rich black pigments and opacifiers made of cassiterite and wollastonite were also identified. The results (type of glaze and deduced processing temperature) were discussed in the light of the ternary phase diagrams visualizing elemental composition determined in previous works and the microstructure examination on the polished section (defining single or multistep firing cycles). Continuity was highlighted on the one hand between the tiles of Bursa, Edirne and Istanbul (Ottoman Iznik-like production) and on the other hand between those of Samarkand area (Timurid) and Iran. The procedure was then applied in the study of three objects (two dishes and a bowl) which are very representative of the productions of the Turkish-Persian cultural areas: a polychrome mina'i cup with decoration representing a rider, an Ottoman Iznik fritware with polychrome floral decoration, and a blue-and-white Safavid ceramic with a decoration representing a shrub. [ABSTRACT FROM AUTHOR]

Influence of nano-glass powder on physico-mechanical properties of geopolymer composite materials has been studied, in addition to studying their firing stability against high temperature from 500 up to 1000 °C. For increasing mechanical, physical as well as firing stability for metakaolin composites; Nano-glass powder was used. Alumino-silicate materials are kaolin, fired kaolin (metakaolin) and limestone all pass 75 µm. Materials prepared at water/binder ratios in a range of 0.40; whereas the used activator 5 M sodium hydroxide with equal volume of liquid sodium silicate. Nano-glass powder added as a partial replacement for metakaolin material in the ratio of 1 up to 9%. Results indicated that compressive strengths of geopolymer mixes incorporating Nano glass powder were obviously higher than those of control one and increased up to 7% followed by slight decrease of on using 9%. Firing of hardened geopolymer results in high thermal resistance up to 500 °C then exposed to decrease up to 800 then increased again at 1000 °C for specimens incorporated 7 and 9% nano-glass powder. However, no micro-cracks were noticed up to 800 °C for all samples as recorded by visual examination of the fired samples. [ABSTRACT FROM AUTHOR]

The present study investigated the potential of utilizing the cutting dust waste generated in the sizing process of volcanic tuff stones as an alternative to the traditional raw materials of industrial floor tile formulations. Within the scope of the research, Döger region (Afyonkarahisar, Turkey) tuff waste was used in varying amounts (up to 7 wt. %) to substitute feldspar (albite) in the industrial formulation partially. The ceramic tiles, which were shaped at 20 MPa pressure by uniaxial pressing from the mixtures obtained by partial substitution of albite by tuff waste, were fired in an industrial furnace at 1180 °C for 50 min. When the pre- and post-firing properties of the tuff waste-incorporated tiles were compared, one could find that 5 wt. % tuff waste incorporation to the industrial formulation provided the highest green (9.83 MPa) and fired (26.77 MPa) strength values, as well as the lowest water absorption (5.77%) value. The results indicated that 5 wt. % substitution of albite with tuff-stone cutting waste could improve the densification and fired strength of ceramic tiles. Furthermore, although it has the potential to be converted into more valuable materials, the use of tuff wastes, which are still disposed of in landfills, in ceramic tile production, will contribute to environmentally friendly solutions and protect the rare natural feldspar deposits. [ABSTRACT FROM AUTHOR]

Pellets from concentrates obtained from the ores of the Sokolov and Sarbai deposits are roasted on conveyor machines. The ores of the deposits differ both in mineralogical and chemical composition. Therefore, it was necessary to study and compare the technological and metallurgical properties of the obtained pellets. At the same time, the firing parameters of the pellets also differ. It was necessary to find out which ore pellets from which deposit have higher metallurgical properties, on the basis of which their production is more preferable. The properties of varieties of concentrates according to the degree of grinding, with different content of silicon oxide, waste rock and sulfur, were studied. At the same time, the fractional composition, true density and specific surface of the concentrates were determined using physicochemical methods. Firing of pellets was studied on a sintering bowl and on a Tamman furnace. After firing, the pellets were tested for strength, the yield of fines, the degree of reduction of the pellets, and their strength during recovery were determined depending on the content of silicon oxide and sulfur in them. The main difference between the concentrates from the ores of the Sokolov and Sarbai deposits, associated with the intensity of their recovery, was established. The results of the study are of interest for technologists in the issue of optimizing regime parameters during the firing of pellets from ore varieties on conveyor machines, and can also be useful in studying the processes of reduction of iron oxides in pellets obtained from the ores of the Sokolov and Sarbai deposits in the zone of indirect reduction in a blast furnace. [ABSTRACT FROM AUTHOR]

The pharmacological profile of cannabigerol (CBG), which acid form constitutes the main precursor of the most abundant cannabinoids, has been scarcely studied. It has been reported to target a2-adrenoceptor and 5-HT1A receptor. The locus coeruleus (LC) and the dorsal raphe nucleus (DRN) are the main serotonergic (5-HT) and noradrenergic (NA) areas in the rat brain, respectively. We aimed to study the effect of CBG on the firing rate of LC NA cells and DRN 5-HT cells and on a2-adrenergic and 5-HT1A autoreceptors by electrophysiological techniques in male Sprague-Dawley rat brain slices. The effect of CBG on the novelty-suppressed feeding test (NSFT) and the elevated plus maze test (EPMT) and the involvement of the 5-HT1A receptor was also studied. CBG (30 µM, 10 min) slightly changed the firing rate of NA cells but failed to alter the inhibitory effect of NA (1-100 µM). However, in the presence of CBG the inhibitory effect of the selective a2- adrenoceptor agonist UK14304 (10 nM) was decreased. Perfusion with CBG (30 µM, 10 min) did not change the firing rate of DRN 5-HT cells or the inhibitory effect of 5-HT (100 µM, 1 min) but it reduced the inhibitory effect of ipsapirone (100 nM). CBG failed to reverse ipsapirone-induced inhibition whereas perfusion with the 5-HT1A receptor antagonist WAY100635 (30 nM) completely restored the firing rate of DRN 5-HT cells. In the EPMT, CBG (10 mg/kg, i.p.) significantly increased the percentage of time the rats spent on the open arms and the number of head-dipping but it reduced the anxiety index. In the NSFT, CBG decreased the time latency to eat in the novel environment but it did not alter home-cage consumption. The effect of CBG on the reduction of latency to feed was prevented by pretreatment with WAY100635 (1 mg/kg, i.p.). In conclusion,CBG hinders the inhibitory effect produced by selective a2-adrenoceptor and 5-HT1A receptor agonists on the firing rate of NA-LC and 5-HT-DRN neurons by a yet unknown indirect mechanism in rat brain slices and produces anxiolytic-like effects through 5-HT1A receptor. [ABSTRACT FROM AUTHOR]

Magnesium aluminate spinel has been prepared by sol–gel synthesis. We have studied the effect of europium and yttrium oxides on the synthesis of magnesium aluminate spinel and kinetics of spinel formation during heat treatment in the temperature range 500–1000°C. According to X-ray diffraction and chemical analysis data, the formation of magnesium aluminate spinel from a dried xerogel prepared from a mixture of the Al(NO3)3 and Mg(NO3)2 compounds in the ratio 2 : 1, respectively, occurred at a temperature of 1000°C and a firing time of 240 min. The resultant material contained free MgO as an impurity phase. The addition of 1.5 wt % Eu2O3 relative to the total weight of the starting mixture reduced the peak spinel formation temperature to 900°C at a firing time of 240 min. In the case of Y2O3, the addition of 3 wt % was needed to maximize spinel formation at this temperature. [ABSTRACT FROM AUTHOR]

The objective of this paper is to learn the possibilities of using biofuel to ensure the heating of indurating machines and assess its impact on the volume of emissions. The main source of fuel was sunflower husk, which can be used in pellet production by the following means: the firing and utilization of fume laden gas as a heat carrier during drying of blend materials and the gasification and utilization of syngas as the fuel in order to heat the indurating machines while thermally treating the pellets. Mathematical simulation was adopted as the research methodology. The results reveal that using biofuel to heat indurating machines during the pelletizing process is technologically feasible. However, there are numerous constraints that are mainly related to environmental issues and logistics. In the course of firing, husk generates additional solid waste and sulfur oxide, although, from the perspective of ESG statistics, it leads to a reduction in the carbon footprint of the end products. Issues related to the handling and storage of biofuel are caused by its aggregate state (solid), low bulk weight, and relatively low calorific value. The abovementioned parameters make biofuel a less favorable source of fuel when compared with natural gas. The aspects of biofuel application shall be considered when planning "energy transition" activities, since they affect economic viability, along with the environment of industrial regions (and the quality of life of inhabitants as well). [ABSTRACT FROM AUTHOR]

Clays from Alhabia (Almería, Spain) have been investigated in this work using several analytical techniques: X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), thermal analysis (Thermogravimetry, TG, and its first derivative, DTG), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). Texture characteristics (granulometry) and plasticity have been examined. The main ceramic properties (firing shrinkage, water absorption, bulk density, open porosity, flexural strength and thermal conductivity) have been determined using pressed and fired clay samples. Thus, the mineralogical, chemical, textural and ceramic features of these clays have been evidenced for the first time. The mineralogical analysis by XRD indicated that the clay samples are constituted by a mixture of chlorite and illite, as main clay minerals, being quartz and other minerals in lower relative proportion (calcite, gypsum and hematite). This finding is important because the investigations on chlorite-illite-calcitic clays are very scarce. The chemical analysis by XRF showed that silica and alumina are predominant, as expected by the mineralogy, with medium contents of calcium oxide, from calcite, and alkalis, from illite, being ∼8 and ∼5%, respectively, besides iron and titanium oxides (∼8%). The particle size analysis showed 71.76% of "clay fraction" (<2 μm) and 21.66% of silt fraction (2–50 μm). The plasticity index (Atterberg) was 14.3%, with acceptable moulding and extrusion properties. Thermal analysis by TG/DTG indicated a weight loss associated to dehydroxylation of structural water of the clay minerals and decarbonation of calcite by progressive heating. After the characterization of raw clays, the next step was the determination of ceramic properties of mixed and ground clays after firing using pressed bodies. For this purpose, two firing temperatures were selected (900 and 1100 °C) for 1 h. The examination of the resultant fired bodies indicated that porous ceramic materials (∼36% open porosity and ∼22% of water absorption capacity) can be obtained by firing at 900 ᵒC, with small variations in dimensions (<0.8% at 1100 °C). The porosity changed at relatively lower values by firing at 1100 °C (∼34–35%), being associated to the presence of decomposed calcite. Bulk density was found almost constant from 900 to 1100 °C, with a maximum value of ∼1.67 g/cm3 at 1100 °C. Flexural strength reached a maximum value of 34.47 MPa at 1100 °C for the ground sample. Finally, thermal conductivity after firing the clay bodies was found almost constant at 900 and 1100 °C (0.457 and 0.479 W/mK, respectively). Taking into account these results, the main applications of the Alhabia clays have been evaluated. These clays can be used for the fabrication of porous ceramic supports and tiles by firing at 900 °C. Firing the clays at higher temperature (1100 °C) is of great interest for the fabrication of ceramic tiles and ceramic bricks of higher flexural strength with variable porosity and practically constant in dimensions. It is economically important although at higher processing costs. Finally, it can be emphasized that this work is a contribution of a better scientific knowledge of chlorite-illite-calcitic clays as ceramic raw materials. [ABSTRACT FROM AUTHOR]

Currently, the amount of man-made waste worldwide is steadily increasing. It is, therefore, necessary to constantly look for effective ways of utilization and recycling. It is also necessary to reduce the use of non-renewable resources and reduce the impact on the environment. The use of coal industry waste is currently quite insignificant, amounting to some 10% of the total volume. The work aimed to study the properties of raw materials and study the processes of structure formation during the forming, drying, and firing of composite ceramic produced using overburden rock and additives. The work's relevance lies in the need to solve environmental, economic, and technological problems related to the utilization of coal mining waste. Experiments of the past prove the possibility of using the waste coal industry as additives in the production of building materials. The article presents the results of studies of the chemical, mineralogical, and granulometric composition of overburden rock in coal mining. Peculiarities of structure formation during the forming, drying, and firing of ceramic composites based on optimal fractional compositions from coal-mine overburden were revealed. Organic and chemical additives were used for the correction of technological properties and improvement of the quality of finished composite products. The physical and mechanical indices of the obtained composite ceramic samples were determined, the analysis of which revealed that the use of highly mineralized carbonaceous rocks as solid additives provided a 2–2.5-fold increase in the strength of the product, 5.6% reduction in water absorption, and an increase in the product frost resistance by 20–25 cycles. The aluminum oxychloride influence on the physical and mechanical indices of the obtained composite articles was reflected in a reduction in their water absorption from 8.2 to 7.0%, a 10–12% increase in strength in compression, and an increase in freeze–thaw resistance by 30–35 cycles. Research results proved that the composition and properties of coal-mine overburden rock are close to those of conventional clays. With special technological preparation, they can be used for the production of composite ceramic products. This will significantly reduce the cost of bricks, to make up for the shortage of high-grade clay raw materials and improve the environmental situation. Nevertheless, further research into the use of coal-mine overburdens in the composite ceramic material technology is warranted. [ABSTRACT FROM AUTHOR]

The paraventricular nucleus of the thalamus (PVT) is involved in drug addiction–related behaviors, and morphine is a widely used opioid for the relief of severe pain. Morphine acts via opioid receptors, but the function of opioid receptors in the PVT has not been fully elucidated. Here, we used in vitro electrophysiology to study neuronal activity and synaptic transmission in the PVT of male and female mice. Activation of opioid receptors suppresses the firing and inhibitory synaptic transmission of PVT neurons in brain slices. On the other hand, the involvement of opioid modulation is reduced after chronic morphine exposure, probably because of desensitization and internalization of opioid receptors in the PVT. Overall, the opioid system is essential for the modulation of PVT activities. [ABSTRACT FROM AUTHOR]

This article presents a publication project concerning the terracottas in the Yale Babylonian Collection that began in 2018, suspended by the pandemic, and resumed in 2022. After defining the difficulties and the methodology, it presents an overview of the study and concludes by describing the publication plan.

Purpose: To evaluate the effect of different firing stages (without firing, additional crystallization and glaze firings), hydrofluoric acid (HF) concentrations (5% and 10%), and thermocycling on the bond strength between resin cement and a zirconia-lithium silicate (ZLS) ceramic. Materials and Methods: ZLS ceramic (Celtra Duo, Dentsply Sirona) blocks were cut into smaller blocks and divided into 12 groups (N = 72), according to the HF concentration used, firing stage, and thermocycling (n = 6). All specimens were silanized (Monobond N, Ivoclar) and cemented with resin cement (Multilink N, Ivoclar) onto blocks of composite resin (Filtek Z250 XT, 3M). The specimens were immersed in distilled water for 24 h. The blocks were cut into sticks and tested immediately or thermocycled for 10,000 cycles in water (5°C-55°C). Microtensile bond strength (μTBS) testing was then performed in a universal testing machine (0.5 mm/min, 50 kgf load cell). The failure modes of the sticks were examined using SEM and classified as adhesive, predominantly adhesive, or cohesive. Fracture surfaces were topographically evaluated using SEM. The 5% and 10% HF groups were analyzed separately and the data submitted to two-way ANOVA and Tukey's test (p < 0.05). Additional samples were used for SEM topographic analysis of representative ceramic surfaces. Results: The most frequent types of failure were predominantly adhesive between cement and ceramic and adhesive (cement completely covered the composite). Statistically significant differences were found only for the thermocycling factor (p < 0.05) for both HF concentrations. However, for the 10% HF groups, a marked decrease in μTBS was observed after firing and thermocycling. SEM showed superficial irregularities on ZLS without etching, partial and total dissolution of the vitreous matrix and exposure of the crystals using 5% and 10% HF, respectively. Conclusion: The crystallization and glaze firings of ZLS ceramics conditioned with 5% HF promoted bond strength maintenance after thermocycling. Thermocycling decreased the bond strength in all groups, but mainly for fired ZLS conditioned with 10% HF. [ABSTRACT FROM AUTHOR]

The pharmacological profile of cannabigerol (CBG), which acid form constitutes the main precursor of the most abundant cannabinoids, has been scarcely studied. It has been reported to target α2-adrenoceptor and 5-HT1A receptor. The locus coeruleus (LC) and the dorsal raphe nucleus (DRN) are the main serotonergic (5-HT) and noradrenergic (NA) areas in the rat brain, respectively. We aimed to study the effect of CBG on the firing rate of LC NA cells and DRN 5-HT cells and on α2-adrenergic and 5-HT1A autoreceptors by electrophysiological techniques in male Sprague-Dawley rat brain slices. The effect of CBG on the novelty-suppressed feeding test (NSFT) and the elevated plus maze test (EPMT) and the involvement of the 5-HT1A receptor was also studied. CBG (30 μM, 10 min) slightly changed the firing rate of NA cells but failed to alter the inhibitory effect of NA (1–100 µM). However, in the presence of CBG the inhibitory effect of the selective α2-adrenoceptor agonist UK14304 (10 nM) was decreased. Perfusion with CBG (30 μM, 10 min) did not change the firing rate of DRN 5-HT cells or the inhibitory effect of 5-HT (100 μM, 1 min) but it reduced the inhibitory effect of ipsapirone (100 nM). CBG failed to reverse ipsapirone-induced inhibition whereas perfusion with the 5-HT1A receptor antagonist WAY100635 (30 nM) completely restored the firing rate of DRN 5-HT cells. In the EPMT, CBG (10 mg/kg, i.p.) significantly increased the percentage of time the rats spent on the open arms and the number of head-dipping but it reduced the anxiety index. In the NSFT, CBG decreased the time latency to eat in the novel environment but it did not alter home-cage consumption. The effect of CBG on the reduction of latency to feed was prevented by pretreatment with WAY100635 (1 mg/kg, i.p.). In conclusion, CBG hinders the inhibitory effect produced by selective α2-adrenoceptor and 5-HT1A receptor agonists on the firing rate of NA-LC and 5-HT-DRN neurons by a yet unknown indirect mechanism in rat brain slices and produces anxiolytic-like effects through 5-HT1A receptor.

A comprehensive investigation of the characteristics of clay from the Gurlan deposit showed that in a chemical formulation Gurlan hydromicaceous clay possesses a relatively high content of iron oxide and alkali oxides as well as fine dispersity and a small amount of finely dispersed free quartz, which make this clay readily fusible. It was also found that the Gurlan clay can be used as a low-temperature fluxing component, instead of cullet, erklez [glass stones], nepheline syenite, etc., in the development of ceramic compositions. [ABSTRACT FROM AUTHOR]

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Porcelain tile manufacturing is an energy-intensive industry that is in dire need of increasing productivity, minimizing costs, and reducing CO2 emissions, while keeping the product quality intact to remain competitive in today's environment. In this contribution, alternative processing parameters for the porcelain tile production sequence were proposed based on simulation-based process optimization. Flowsheet simulations in the Dyssol framework were used to study the impact of the milling and firing process parameters on the electrical and thermal energy consumption, final product quality, and productivity of the entire processing sequence. For this purpose, a new model of gas flow consumption in the sintering stage was proposed and implemented. During optimization, the primary condition was to maintain the product quality by keeping the final open porosity of the tile within the specified industrial range. The proposed simulation methodology proved to be effective in predicting the influence of the processing parameters on the intermediate and final products of the manufacturing sequence, as well as in estimating the production costs for the Brazilian and Spanish economic conditions. This approach has shown great potential to promote digitalization and establish digital twins in ceramic tile manufacturing for further in-line process control. [ABSTRACT FROM AUTHOR]

It is established that firing samples (granules) in a layer of fluxed magnetite iron ore concentrates are accompanied by complex physicochemical processes related to the oxidation of magnetite and the decomposition of carbonates. When they are heated, along with heat exchange processes, mass transfer processes also occur. These processes are interrelated and affect each other, as well as the degree of completion of the processes of oxidation and decarbonization in the layer. The oxidation mechanism of the samples containing magnetite is considered. A model of the mass transfer process for the period of decomposition of carbonates is refined. An equation is proposed that describes the kinetics of magnetite oxidation in samples upon heating for a more general form of boundary conditions. An equation is presented that makes it possible to determine the rate constant of the oxidation process depending on the characteristics of the heat-carrier gas and the properties of the material. A calculation procedure is developed to determine the diffusion coefficient of oxygen in the combustion products of various fuels. Experiments are carried out to study the kinetics of oxidation and decarbonization processes in a layer of granules on an experimental setup, which make it possible to simulate these processes in relation to different periods of their heat treatment in thermal plants and determine the mass transfer coefficients. This will make it possible to determine the degree of completion of processes by the height of the layer at the given values of the temperature and duration of firing. [ABSTRACT FROM AUTHOR]

The article considers the possibility of replacing traditional mineral raw materials (dolomite and asbestos) to obtain thermal insulating material - sovelite - with technogenic raw materials, i.e. tails of polymetallic ores (dolomitebarium tails) and synthetic wollastonite, obtained on the basis of phosphoric slag. The research results allowed us to establish that the dolomite-barium "tails" can serve as a technogenic raw material base to obtain thermal insulating material - sovelite. The advantages of the proposed technology to obtain thermal insulating material -sovelite- in comparison with the traditional one allow for reducing energy costs for production due to the absence of stages of raw material extraction, crushing, and grinding, a reduced firing temperature, the absence of the stage of grinding the fired product since during firing there is waste dispersion, natural dolomite saving, replacement of expensive natural reinforcing material - chrysotile asbestos-with synthetic wollastonite, obtained on the basis of phosphoric slag. The use of synthetic wollastonite significantly improves the quality characteristics and increases the service life of the products. [ABSTRACT FROM AUTHOR]

Function-as-a-Service (FaaS) has become a mainstream cloud computing paradigm for developers to build cloud-native applications in recent years. By taking advantage of serverless architecture, FaaS applications bring many desirable benefits, including built-in scalability, high availability, and improved cost-effectiveness. However, predictability and trade-off of performance and cost are still key pitfalls for FaaS applications due to poor infrastructure transparency and lack of performance and cost models that fit the new paradigm. In this study, we therefore fill this gap by proposing formal performance and cost modeling and optimization algorithms, which enable accurate prediction and fine-grained control over the performance and cost of FaaS applications. The proposed model and algorithms provide better predictability and trade-off of performance and cost for FaaS applications, which help developers to make informed decisions on cost reduction, performance improvement, and configuration optimization. We validate the proposed model and algorithms via extensive experiments on AWS. We show that the modeling algorithms can accurately estimate critical metrics, including response time, cost, exit status, and their distributions, regardless of the complexity and scale of the application workflow. Also, the depth-first bottleneck alleviation algorithm for trade-off analysis can effectively solve two optimization problems with fine-grained constraints. [ABSTRACT FROM AUTHOR]

We developed and tested the methodology that supports the identification of individual motor unit (MU) firings from the Hoffman (or H) reflex recorded by surface high-density EMG (HD-EMG). Synthetic HD-EMG signals were constructed from simulated 10% to 90% of maximum voluntary contraction (MVC), followed by 100 simulated H-reflexes. In each H-reflex the MU firings were normally distributed with mean latency of 20 ms and standard deviations (SDLAT) ranging from 0.1 to 1.3 ms. Experimental H-reflexes were recorded from the soleus muscle of 12 men (33.6 ± 5.8 years) using HD-EMG array of ${5}\times {13}$ surface electrodes. Participants performed 15 to 20 s long voluntary plantarflexions with contraction levels ranging from 10% to 70% MVC. Afterwards, at least 60 H-reflexes were electrically elicited at three levels of background muscle activity: rest, 10% and 20% MVC. HD-EMGs of voluntary contractions were decomposed using the Convolution Kernel Compensation method to estimate the MU filters. When applied to HD-EMG signals with synthetic H reflexes, MU filters demonstrated high MU identification accuracy, especially for $\text {SD}_{\text {LAT}}>{0.3}$ ms. When applied to experimental H-reflex recordings, the MU filters identified 14.1 ± 12.1, 18.2 ± 12.1 and 20.8 ± 8.7 firings per H-reflex, with individual MU firing latencies of 35.9 ± 3.3, 35.1 ± 3.0 and 34.6 ± 3.3 ms for rest, 10% and 20% MVC background muscle activity, respectively. Standard deviation of MU latencies across experimental H-reflexes were 1.0 ± 0.8, 1.3 ± 1.1 and 1.5 ± 1.2 ms, in agreement with intramuscular EMG studies. [ABSTRACT FROM AUTHOR]

Introduction: Color matching between a zirconia-based ceramic restoration and a natural tooth is a common clinical challenge. This in-vitro study aimed to assess the effects of the number of firing cycles and zirconia core translucency on the color stability and surface roughness in two zirconia-based ceramic systems. Materials and Method: A total of 60 disk-shaped zirconia specimens (10×1 mm) were prepared in high and low translucencies (n=30 per group), veneered with 1mm ceramic layers, and subjected to 3, 5, and 7 firing cycles in three respective subgroups (n=10). Color stability (∆E) and surface roughness (Ra(µm)) parameters were measured after soaking the specimens in coffee solution and using a spectrophotometer and profilometer, respectively. Data were analyzed using two-way ANOVA and Tukey’s post hoc test (α=0.05). Results: The number of firing cycles affected the Ra value in both zirconia-based ceramic systems (P