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Background: Pseudomonas aeruginosa (P. aeruginosa) is widely distributed in air, soil, and water, human respiratory tract, intestinal tract, and skin. It can induce bloodstream infection, urinary tract infection, gastrointestinal tract infection, respiratory tract infection, etc. Conventional bacterial isolation, culture, and identification are time-consuming, and many false negative results, which cannot meet the needs of precise clinical diagnosis，and proper treatment. This study aims to develop a rapid isothermal amplification assay of Pseudomonas aeruginosa. Methods: Specific primers were designed according to the National Center for Biotechnology Information (NCBI) database based on the highly conserved sequence of Pseudomonas aeruginosa virulence factor gene lecA, and a recombinase polymerase amplification (RPA) detection method was established. The sensitivity and specificity were calculated, as well as the collection and processing of clinical samples. Results: The thermostatic amplification technique for Pseudomonas aeruginosa established in this paper allows nucleic acid detection within 10 minutes without cross-amplification with other bacterial strains. 27 P. aeruginosa infections were accurately detected in 300 clinical samples. Conclusion: The rapid detection system based on thermostatic amplification had shown high sensitivity and specificity in this study, indicated that this method can effectively assist clinical bacterial detection. [ABSTRACT FROM AUTHOR]

This paper examines how steel fiber and the amount of lightweight expanded clay aggregate (LECA) affect the mechanical and microstructural properties of geopolymer concrete (GPC) made from fly ash after being heated. LECA has been used with different contents (0, 10, and 20%) as a partial replacement by weight of coarse aggregate. Steel fiber has been employed in GPC with volume fractions of 0 and 1%. A slump test was applied to examine the workability of fresh concrete. Compressive strength, splitting tensile strength, flexural strength, and elastic modulus tests also measured the mechanical properties. Furthermore, the microstructure characterization was also carried out by performing scanning electron microscopy (SEM). The findings suggest that including steel fiber and raising the LECA content in the mixture enhanced the strength's retention following high-temperature exposure. After being exposed to a constant temperature of 800°C, GPC containing steel fiber and 20% LECA achieved the best result compared to the plain GPC in terms of decrease in mass, residual compressive and tensile strengths, residual flexural strength, and residual amount of elastic modulus: 6.04 and 4.39%; 27.08 and 39.27%; 37.6 and 47.02%; 16.07 and 30.3, and 2.17 and 6.19%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

Background Pseudomonas aeruginosa (P. aeruginosa) is widely distributed in air, soil, and water, human respiratory tract, intestinal tract, and skin. It can induce bloodstream infection, urinary tract infection, gastrointestinal tract infection, respiratory tract infection, etc. Conventional bacterial isolation, culture, and identification are time-consuming, and many false negative results, which cannot meet the needs of precise clinical diagnosis，and proper treatment. This study aims to develop a rapid isothermal amplification assay of Pseudomonas aeruginosa.Methods Specific primers were designed according to the National Center for Biotechnology Information (NCBI) database based on the highly conserved sequence of Pseudomonas aeruginosa virulence factor gene lecA, and a recombinase polymerase amplification (RPA) detection method was established. The sensitivity and specificity were calculated, as well as the collection and processing of clinical samples.Results The thermostatic amplification technique for Pseudomonas aeruginosa established in this paper allows nucleic acid detection within 10 minutes without cross-amplification with other bacterial strains. 27 P. aeruginosa infections were accurately detected in 300 clinical samples.Conclusion The rapid detection system based on thermostatic amplification had shown high sensitivity and specificity in this study, indicated that this method can effectively assist clinical bacterial detection.

The durability of geopolymer concrete containing Ground Granulated Blast Furnace Slag (GGBS) and Rice Husk Ash (RHA), along with Lightweight Expanded Clay Aggregate (LECA), was investigated. Six different LWGPC mixtures were made with NaOH molarities of 8, 10, and 12M. For each molarity, two combinations of source materials were selected: 100% GGBS (G) and 80% GGBS with 20% RHA (RG). In all the mixtures, coarse aggregate was substituted with 35% LECA. LWGPC mixtures were exposed to 3% HCl, 5% MgSO4, and 3.5% NaCl for studying the durability properties. The test results demonstrate that 100% GGBS with 12M NaOH (12G) outperformed all other mixtures. The residual compressive strength of 12G mix LWGPC specimens after six months of exposure was found to be 86.4% in an acid environment, 90.6% in a sulfate environment, and 91.4% in a salt environment. The elemental composition analyzed using EDAX reveals that silica, alumina, calcium, and sodium are the predominant elements that form a dense microstructure with N-A-S-H, C-A-S-H, and C-S-H. Further, the inner properties of the specimens exposed to chemicals were examined using MATLAB R2023b and ImageJ 1.54f based on SEM images. The SEM image showed that the porosity of LWGPC specimens ranged from 0.5194 to 0.6748 µm, signifying an enhanced durability performance. The experimental results and microstructural analysis show that the LWGPC incorporating RHA and GGBS with LECA offers a superior performance, making it a promising solution for sustainable and durable construction. [ABSTRACT FROM AUTHOR]

A versatile building material, foamed concrete is made of cement, fine aggregate, and foam combined with coarse aggregate. This study provides a description of how constant coarse aggregate replacement (50%) of LECA and foamed concrete, which are lightweight concrete types, by zeolite as a filler and PEG-400 as a plasticizer, water retention agent, and strength enhancer affect the mechanical properties of the cement. A study that examined the characteristics of cellular lightweight concrete in both its fresh and hardened forms was carried out for both foamed concrete and LECA concrete. In order to do this, a composite of zeolite and polyethylene glycol 400 was made using the direct absorption method, and no leakage was seen. Zeolite was loaded to a level of 10% and 20% of the total weight in cement, while 400 g/mol PEG was used at levels of 1%, 1.5%, and 2% of the cement's weight. Various mixtures having a dry density of 1250 kg/m3 were produced. Properties like dry density, splitting tensile strength, and compressive strength were measured. An increase in the amount of PEG400–zeolite was seen to lower the workability, or slump, of both foamed and LECA concrete, while the replacement of aggregate by zeolite resulted in an exponential drop in both compressive and flexural strengths. [ABSTRACT FROM AUTHOR]

This study investigates fresh and hardened self-compacting concrete properties. LECA will be used in place of coarse aggregate in (0, 20, 40, and 60) % proportions in a partial replacement. First, four SCC mixes were made based on LECA volume fraction and then the second group was made by adding 1% glass fiber by volume to group one's mixes. Hardened concrete after 7, 28, and 56 days was tested for density, water absorption, and (compressive, splitting tensile, and flexural) strengths. Results suggest that LECA increases workability. Rising LECA percentage decreases compressive strength; for 60% LECA, the decrease was (51.90, 45.34, and 41.26) % for 7, 28, and 56 days, respectively. With 60% LECA replacement, flexural strength decreased by (54.38, 33.80, and 32.78) % for 7, 28, and 56 days, respectively. Density drops significantly with LECA, reaching its lower density at (60) % of LECA. Water absorption rises with the increase of LECA. After adding glass fiber workability dropped significantly, and hardened characteristics improved. Compressive strength increased slightly compared to the same mixtures without glass fibers. At20% of LECA the compressive strength increased by (5.58%) at 28 days compared to (60%) LECA at which the compressive strength increased by (3.82%). Glass fiber addition increased flexural strength significantly compared to the same mixes without glass fibers. The mixture with (20%) LECA had the greatest increase (24.46%) in 28 days, compared to the mix with (60%) LECA (18.22%). Density increased slightly with glass fibers. Glass fibers increase water absorption compared to the same mixes without glass fiber.

The borders between cell and developmental biology, which have always been permeable, have largely dissolved. One manifestation is the blossoming of cilia biology, with cell and developmental approaches (increasingly complemented by human genetics, structural insights, and computational analysis) fruitfully advancing understanding of this fascinating, multifunctional organelle. The last eukaryotic common ancestor probably possessed a motile cilium, providing evolution with ample opportunity to adapt cilia to many jobs. Over the last decades, we have learned how non-motile, primary cilia play important roles in intercellular communication. Reflecting their diverse motility and signaling functions, compromised cilia cause a diverse range of diseases collectively called ciliopathies. In this review, we highlight how cilia signal, focusing on how second messengers generated in cilia convey distinct information; how cilia are a potential source of signals to other cells; how evolution may have shaped ciliary function; and how cilia research may address thorny outstanding questions.

This study describes an experimental research focusing on the behaviour of Lightweight Aggregate Wide Reinforced Concrete Beams (LAWRCB) using shear steel plates. This technique represents an inexpensive way which reduces structural and building complexities. Wide beams can provide adequate cross-sectional areas to meet the specified capacity in a shallower depth than a system of narrower beams placed similarly in the design. Also, WB treats the crowd of stirrups because the shear component provided by concrete is very small compared with high depth concrete Beams. This research is also trying to minimize the weight of a wide concrete beam using light weight concrete instead of using conventional concrete which has effects on the deflection, crack patterns, and load carrying capacity. This investigation consists of reviewing the previous work and an experimental program consisting of testing mixes to produce lightweight concrete. In addition, several simply supported wide beams with various parametric studies will be designed, cast, and tested. After the specimen tests are carried out, comparisons and discussions of the results will be made with code requirements.

Self-Compacting Concrete (SCC) is a concrete with high workability. It fills the molds and passes between the narrow openings of reinforcing steel bars without the need for any mechanical pressure or compaction and without the need of a vibrator. Structural Lightweight Self Compacting Concrete (SLWSCC) is an innovative concrete developed in recent years. This concrete type combines the characteristics of lightweight concrete and SCC. This study focused on preparing the appropriate mixture to obtain SLWSCC by using Lightweight Expanded Clay Aggregate (LECA) as a volumetric partial replacement of coarse aggregate by 20, 40, 60, and 80%, reinforced by volumetric ratios of single and hybrid Micro steel Fiber (MF) and Hooked steel Fiber (HF) of 1.5 MF, 0.75 HF+0.75 MF, 1 HF+0.5 MF, and 1.5 HF (%) to evaluate the fresh properties through slump flow, T500mm, V-funnel, L-box, and segregation tests. The results showed that all mixtures fell within the limits of EFNARC/2005. It was found that single and hybrid fiber addition reduces slump flow, L-box, and segregation, while the T500mm and V-funnel values increased. The hard properties of SLWSCC reinforced by fibers, such as compressive strength, flexural strength, splitting tensile strength, oven dry density, and water absorption were studied. The addition of fibers raises compressive, splitting tensile, and flexural strength, with the maximum augmentation of 21.4, 43.4, and 53.8%, respectively, occurring when adding 1 HF + 0.5 MF. The highest value of oven dry density was acquired when adding 1.5 MF and the highest water absorption rate was acquired after the addition of 1.5 HF. [ABSTRACT FROM AUTHOR]

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

This study describes an experimental research focusing on the behaviour of Lightweight Aggregate Wide Reinforced Concrete Beams (LAWRCB) using shear steel plates. This technique represents an inexpensive way which reduces structural and building complexities. Wide beams can provide adequate cross-sectional areas to meet the specified capacity in a shallower depth than a system of narrower beams placed similarly in the design. Also, WB treats the crowd of stirrups because the shear component provided by concrete is very small compared with high depth concrete Beams. This research is also trying to minimize the weight of a wide concrete beam using light weight concrete instead of using conventional concrete which has effects on the deflection, crack patterns, and load carrying capacity. This investigation consists of reviewing the previous work and an experimental program consisting of testing mixes to produce lightweight concrete. In addition, several simply supported wide beams with various parametric studies will be designed, cast, and tested. After the specimen tests are carried out, comparisons and discussions of the results will be made with code requirements. [ABSTRACT FROM AUTHOR]

Abstract In the present work, an exhaustive analysis of an Argentinian commercial LECA with a multi-technique approach was successfully carried out. Five sub-types of samples were considered to study the degree of macroscopic homogeneity of the LECAs, which presented observable differences in color and morphology. The microstructural, textural, and mineralogical features of the aggregates within each category were assessed and the differences among them were described and discussed. The density values of the samples studied were between 1.01 and 1.20 g/cm3 and porosity percentages were in the range of 24 to 33 %. The samples present a similar mineralogical composition with quartz and anorthite as the main crystalline phases and almost 50 wt. % of non-crystalline phase. In addition, some variations in the Rietveld quantification were analyzed. The main challenge of LECAs industrial production is to control the raw materials and the process to obtain homogeneous LECAs with similar performance. In this regard, this type of analysis is useful for establishing and comparing some characterization strategies to control, select, design, and evaluate new LECAs.

A novel lightweight aggregate concrete (LWAC) or lightweight concrete (LWC) is developed using expanded perlite powder and lightweight expanded clay aggregate as a replacement for conventional fine and coarse aggregates, respectively. Furthermore, the natural plant-based flax fibre in treated form was added to the LWC mix at three different volume fractions. The mechanical and thermal characterisation of LWC was carried out using the compressive strength test, split tensile test, modulus of rupture, thermal conductivity and thermal resistance test. Moreover, the microstructural and durability properties were obtained using scanning electron microscopy/energy dispersive X-ray spectrum analysis, rapid chloride penetration test, sorptivity test and water absorption test. Test results reveal that the addition of 2.0% flax fibre resulted in improved mechanical, thermal and durability properties when compared to LWC with no fibres. Moreover, the microstructural analysis using SEM revealed the formation of ettringite which is responsible for the strength development in the LWAC mix. [ABSTRACT FROM AUTHOR]

The world is moving towards the use of sustainable concrete due to its ability to reduce environmental pollution caused by the presence of waste arising from the demolishing of old buildings or those collapsed as a consequence of earthquakes. The combined effects of fine recycled concrete aggregate (RF), light expanded clay coarse aggregate (LECA), and steel fibres (SF) on the properties of concrete were investigated in the present study. The evaluated properties were slump test, compressive strength, flexural strength, splitting tensile strength, density, and water absorption. The prepared concrete specimens were also evaluated, considering non-destructive tests through ultrasonic pulse velocity and rebound hammer tests. Findings indicated that the inclusion of RF with LECA as a partial and full replacement of gravel in both fibrous and non-fibrous concrete resulted in a drop in compressive, splitting, and flexural strength by an average of 17%, 22%, and 25%, respectively when 50% LECA was used. Furthermore, when 100% LECA was used, the drop became more pronounced, with decreases of 39%, 42%, and 45%, respectively. However, the use of hooked steel fibre at 0.75% compensated for this adverseness, and the strengths of the mixes were generally higher than those of the reference mix, which was produced with normal-weight aggregates. [ABSTRACT FROM AUTHOR]

This paper presents reclamation of greywater using "Green-wall treatment system". A Green-wall of capacity 100 L/d has been implemented with the aim of greywater reclamation from a bathing water facility. The treatment system comprised of a degreasing tank of size 0.9 m x 0.9 m x 0.3 m for oil & grease removal, followed by a Green-wall. Removal of oil & grease has been done along with commonly observed pollutants in greywater, to prevent clogging of filler material. In stage-I studies, Green-wall pots are filled with 4-10 mm Ø inert filler material LECA and in stage-II, LECA is mixed with locally available coconut peat in equal proportion. Stage-I studies using LECA indicated that maximum achievable HRT is 12 h and the treated greywater with respect to BOD does not comply with USEPA (2012) norms for landscape irrigation. In stage-II, the optimized performance is observed at 16 &18 h HRT at hydraulic loading rate 67-70 L/m²/d, when compared with 14 and 12 h HRT. Treated greywater quality met the prescribed permissible limits with respect to BOD, TSS and FC and is observed to be innocuous in terms of the reuse options for agriculture and landscape irrigation. In stage-II, the BOD, COD, TSS and FC reduce from 48 to 10 mg/L, 58 to 18 mg/L, 96 to 10 mg/L and 400 CFU/ 100 mL to below detectable limits, respectively, at 18 h HRT. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

This research aims to produce lightweight self-compacting concrete (LWSCC) using lightweight expanded clay aggregate (LECA) as coarse aggregate. The additional aim is to study the influence of steel fiber and hybrid fibers (steel and polypropylene (PP)) on the properties of LWSCC in fresh and hardened state. Furthermore, compressive, tensile, and flexural strengths of LWSCC specimens (with and without fibers) are tested after being subjected to the fire exposure. In this study, four LWSCC mixtures with different fiber percentages (0 % fiber, 1 % steel, 0.75 % steel + 0.25 % PP, and 0.5 % steel + 0.5 % PP) are prepared and tested. The specimens were burned at temperatures 25, 300, 400, and 600 °C. The results show that all mixtures have excellent resistance to segregation and high ability to filling and passing. The presence of fibers slightly reduced the workability of LWSCC. The mechanical properties of LWSSC decrease with increasing temperature. The results show that mixtures containing fibers have good mechanical qualities and spalling resistance compared to mixtures without fibers when exposed to fire.

The durability of geopolymer concrete containing Ground Granulated Blast Furnace Slag (GGBS) and Rice Husk Ash (RHA), along with Lightweight Expanded Clay Aggregate (LECA), was investigated. Six different LWGPC mixtures were made with NaOH molarities of 8, 10, and 12M. For each molarity, two combinations of source materials were selected: 100% GGBS (G) and 80% GGBS with 20% RHA (RG). In all the mixtures, coarse aggregate was substituted with 35% LECA. LWGPC mixtures were exposed to 3% HCl, 5% MgSO4, and 3.5% NaCl for studying the durability properties. The test results demonstrate that 100% GGBS with 12M NaOH (12G) outperformed all other mixtures. The residual compressive strength of 12G mix LWGPC specimens after six months of exposure was found to be 86.4% in an acid environment, 90.6% in a sulfate environment, and 91.4% in a salt environment. The elemental composition analyzed using EDAX reveals that silica, alumina, calcium, and sodium are the predominant elements that form a dense microstructure with N-A-S-H, C-A-S-H, and C-S-H. Further, the inner properties of the specimens exposed to chemicals were examined using MATLAB R2023b and ImageJ 1.54f based on SEM images. The SEM image showed that the porosity of LWGPC specimens ranged from 0.5194 to 0.6748 µm, signifying an enhanced durability performance. The experimental results and microstructural analysis show that the LWGPC incorporating RHA and GGBS with LECA offers a superior performance, making it a promising solution for sustainable and durable construction.

A versatile building material, foamed concrete is made of cement, fine aggregate, and foam combined with coarse aggregate. This study provides a description of how constant coarse aggregate replacement (50%) of LECA and foamed concrete, which are lightweight concrete types, by zeolite as a filler and PEG-400 as a plasticizer, water retention agent, and strength enhancer affect the mechanical properties of the cement. A study that examined the characteristics of cellular lightweight concrete in both its fresh and hardened forms was carried out for both foamed concrete and LECA concrete. In order to do this, a composite of zeolite and polyethylene glycol 400 was made using the direct absorption method, and no leakage was seen. Zeolite was loaded to a level of 10% and 20% of the total weight in cement, while 400 g/mol PEG was used at levels of 1%, 1.5%, and 2% of the cement’s weight. Various mixtures having a dry density of 1250 kg/m3 were produced. Properties like dry density, splitting tensile strength, and compressive strength were measured. An increase in the amount of PEG400–zeolite was seen to lower the workability, or slump, of both foamed and LECA concrete, while the replacement of aggregate by zeolite resulted in an exponential drop in both compressive and flexural strengths.

Concrete quality control tests usually focus on the compressive strength of concrete, while neglecting other important properties such as impact and explosion resistance, which are essential for creating resilient concrete structures. Additionally, in the process of refining sugarcane, Bagasse, a yellow fiber that is considered a waste product, is produced. Khuzestan province alone produces around one million tons of Bagasse annually, which leads to environmental concerns. To address these issues, this research investigates the mechanical properties and impact resistance of concrete containing lightweight LECA aggregates and Bagasse fibers under compressive and impact loads. Initially, a target mix scheme is determined, and samples are made and tested after curing without the addition of Bagasse and LECA. Then, samples are made with the mentioned mixing design and the combination of Bagasse and LECA by weight ratio of (Bagasse unit, LECA unit). Additionally, samples using LECA (without Bagasse) with 10%, 20%, and 30% replacement of aggregates are made and tested after curing. Compressive and impact tests are performed on all samples in accordance with regulations using appropriate testing machines and procedures. Results indicate that concrete containing lightweight LECA and Bagasse fibers has a higher impact resistance than ordinary concrete, and that the use of LECA in concrete can create structural lightweight concrete.

Core mitochondrial processes such as the electron transport chain, protein translation and the formation of Fe–S clusters (ISC) are of prokaryotic origin and were present in the bacterial ancestor of mitochondria. In animal and fungal models, a family of small Leu-Tyr-Arg motif-containing proteins (LYRMs) uniformly regulates the function of mitochondrial complexes involved in these processes. The action of LYRMs is contingent upon their binding to the acylated form of acyl carrier protein (ACP). This study demonstrates that LYRMs are structurally and evolutionarily related proteins characterized by a core triplet of α-helices. Their widespread distribution across eukaryotes suggests that 12 specialized LYRMs were likely present in the last eukaryotic common ancestor to regulate the assembly and folding of the subunits that are conserved in bacteria but that lack LYRM homologues. The secondary reduction of mitochondria to anoxic environments has rendered the function of LYRMs and their interaction with acylated ACP dispensable. Consequently, these findings strongly suggest that early eukaryotes installed LYRMs in aerobic mitochondria as orchestrated switches, essential for regulating core metabolism and ATP production.

. The primary goal of this investigation is to study the effect of using mono and hybrid fibers on the fresh and hardened characteristics of Lightweight Self-Compacting Concrete (LWSCC). Slump flow test, L-box test, sieve segregation test, and V-funnel test were used to evaluate the workability of LWSCC. The mechanical characteristics of LWSCC were assessed by using compressive strength, splitting strength, and flexural strength. Four mixtures using two types of fiber: Steel fiber (St) and polypropylene fiber (PP) (0% fiber, 1% (St), 0.75% (St) +0.25% (PP), 0.5% (St) +0.5% (PP)) were made. According to the results, (St) fiber and hybrid fiber addition to LWSCC reduced its workability, although the values of tests were still within the acceptable range stander of EFNARC. The findings indicated a decrease in the values of slump flow and L-box test by adding mono and hybrid fibers to the LWSCC mixture. While the T500mm and V_ funnel tests increased by adding mono and hybrid fibers to LWSCC mixture. The results also indicate that the utilisation of (St) fiber and hybrid fibers had a significant effect on the mechanical characteristics of LWSCC. Where the flexural and splitting strengths significantly increase with the addition of (St) and hybrid fibers to the LWSCC mix.

Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively. Finally, using more glass fibers did not necessarily result in improved mechanical properties. More ideal properties can be obtained by controlling the LECA content and glass fibers ratio. After conducting tests, narrowing down the glass fiber content range up to 2%, along with LECA content of 75% and 85%, is highly recommended for obtaining the best behavior of glass fiber-reinforced LECA concrete.

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

In some construction industries, there are difficulties in achieving the required concrete compaction, Self-compaction is an alternative option. Working with self-compaction self-curing concrete requires a unique approach. This study aims to examine the possibility of producing self- compacting concrete with normal and high self-cure rates. This research observed how both the self- curing and self-compacting concrete behaved under normal and high-strength conditions. Two stages were prepared for this investigation. The first stage of this research studied the effect of a curing agent on the fundamental characteristics of both normal-strength and high-strength self-compacting concrete, with the aim of achieving self-curing self-compacting concrete. The primary variables of this study include the grade of concrete, the type of curing agent, the reinforcing bars, and the dosage of these variables. In the second stage, reinforced concrete beams were cast with one of the two proposed concrete types, and their behavior was studied. The findings were analyzed in terms of the beginning cracking loads, the ultimate loads, and the crack patterns of the testing beams. According to the results, both the normal-strength and the high-strength varieties of self-curing self-compacting concrete are effective in providing structural features, which are absent from the processes of curing and compacting. Curing chemicals are utilized to mitigate the process of water evaporation in self-compacting concrete, hence enhancing the water retention capabilities of self-compacting concretes that possess enough hardened concrete characteristics.

Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively. Finally, using more glass fibers did not necessarily result in improved mechanical properties. More ideal properties can be obtained by controlling the LECA content and glass fibers ratio. After conducting tests, narrowing down the glass fiber content range up to 2%, along with LECA content of 75% and 85%, is highly recommended for obtaining the best behavior of glass fiber-reinforced LECA concrete. [ABSTRACT FROM AUTHOR]

Currently, the growth of building construction and the need for lighter but more sustainable materials are of interest. Additionally, recent fire incidents highlight the insufficient knowledge of the properties of materials after a fire. Common materials such as concrete should, to minimize their adverse environmental effects and expenses, be maintained in such a way as to increase their resistance and preserve their mechanical properties when subjected to high temperatures. Hence, in this research, the post-fire mechanical degradation of lightweight concrete (LWC) has been investigated. Moreover, the addition of steel fiber and nano-silica have been studied in terms of their ability to reduce the mechanical degradation of LWC subjected to high temperatures. For this purpose, different samples were considered in four mixture designs: the LWC samples, samples with steel fibers, samples with nano-silica, and samples with a combination of steel fibers and nano-silica. All samples were subjected to temperatures of 200, 400 and 600 degrees Celsius and compared with the control samples. The results show that, as the temperature increased, the tensile and compressive resistances of LWC decreased. The samples without fibers and nano-silica showed a greater decrease in mechanical properties with increasing temperature. The addition of steel fibers and nano-silica, individually or as a combination, can improve the compressive and tensile strength of the concrete both at room temperature and at higher temperatures. [ABSTRACT FROM AUTHOR]

This study deals with the intelligent modeling of reactive yellow 84 dye removal from aqueous solutions by zinc oxide (ZnO) nanoparticles based on inorganic light expanded clay aggregates. Accordingly, a set of experimental data were utilized to develop robust models by adjusting the initial feed concentration, initial pH, de-colorization time, catalyst concentration, and lamp power as input factors. The Leverage method, a common method for detecting outliers, proved all measured data were reliable. After definition of input factors, four intelligent approaches, i.e., multilayer perceptron, Gaussian process regression (GPR), radial basis function, and adaptive neuro fuzzy inference system with subtractive clustering were used to establish exact models for predicting the dye removal. Among them, the GPR-based model produced the best results with AARE, RRMSE, and R2 values of 4.87%, 6.21%, and 97.31%, respectively, for the test dataset. The remaining models also provided satisfactory outputs with AAREs between 6.59% and 9.81%. In addition, the influence of each operating parameter on the dye removal was properly described for the novel models. Finally, the most effective parameters on removal performance were determined by using a sensitivity analysis based on the GPR model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

This study investigates the development of sustainable precast concrete sandwich wall panels using alternative materials. This study explores the partial replacement of natural aggregates with Lightweight Expanded Clay Aggregate (LECA) and marble waste aggregate while utilizing fly ash as a partial cement substitute. The experimental panels were constructed using self-compacting concrete mixes with varying proportions of these materials. The panels consisted of two steel fiber-reinforced concrete wythes joined by basalt fiber-reinforced polymer connectors, with expanded polystyrene insulation. Full-scale wall panels underwent flexural testing according to ASTM standards. The results indicate that alternative materials affect panel performance in terms of strength, ductility, and energy absorption. Panels with 20% LECA exhibited the best thermal performance, achieving a U-value of 0.363 W/m2·K, surpassing the energy code standards. The mixture containing 100% marble waste exhibited the highest flexural strength. Sustainable panels were estimated to be 28% cheaper in terms of raw material costs than conventional panels. The study achieved significant CO2 savings of approximately 240 kg per ton of concrete when 30% of cement was replaced with fly ash. These findings underscore the viability of incorporating sustainable materials into precast concrete sandwich panels, offering a promising path toward more environmentally conscious and energy-efficient building practices.

The ability to produce load-bearing masonry units adopting ACI 211.1 mix design using (1:3.2:2.5) as (cement: fine aggregate: coarse aggregate) with slump range (25-50mm) which can conform (dimension, absorption, and compressive strength) within IQS 1077/1987 requirements type A was our main goal of the study. The ability to use low cement content (300 kg/m3) to handle our market price products since the most consumption in wall construction for low-cost buildings was encouraging. The use of (10 and 20%) of LECA as partial volume replacement of coarse aggregate to reduce the huge weight of masonry blocks can also be recommended. The types of production of the load-bearing masonry units were A and B for (10 and 20%), respectively. Finally, the use of the spray curing method was the more suitable simulation of reality and easier for factory producers, taking into consideration that the increasing curing time from 14 days (recommended in IQS 1077/1987) to 28 days may be led to conversation masonry type from B to A as in R20%-300.

Mitoviruses are small vertically transmitted RNA viruses found in fungi, plants and animals. Taxonomically, a total of 105 species and 4 genera have been formally recognized by ICTV, and recently, 18 new putative species have been included in a new proposed genus. Transcriptomic and metatranscriptomic studies are a major source of countless new virus-like sequences that are continually being added to open databases and these may be good sources for identifying new putative mitoviruses. The search for mitovirus-like sequences in the NCBI databases resulted in the discovery of more than one hundred new putative mitoviruses, with important implications for taxonomy and also for the evolutionary scenario. Here, we propose the inclusion of four new putative members to the genus Kvaramitovirus, and the existence of a new large basally divergent lineage composed of 144 members that lack internal UGA codons (subfamily "Arkeomitovirinae"), a feature not shared by the vast majority of mitoviruses. Finally, a taxonomic categorization proposal and a detailed description of the evolutionary history of mitoviruses were carried out. This in silico study supports the hypothesis of the existence of a basally divergent lineage that could have had an impact on the early evolutionary history of mitoviruses. [ABSTRACT FROM AUTHOR]

Limited information and data are available on the material and structural performance of GC incorporating lightweight fine aggregate. In this research, three types of lightweight fine materials were utilized to partially replace sand volume of GC. These lightweight materials were rubber, vermiculite, or lightweight expanded clay aggregate (LECA) and they were used in contents of 20%, 40%, 60%, and 100%. The variables were applied to better investigate the efficiency of each lightweight material in GC and to recommend GC mixes for structural applications. The concrete workability, compressive strength, indirect tensile strength, freezing and thawing performance, and impact resistance were measured in this study. In addition, three reinforced concrete slabs were made from selected mixes with similar compressive strength of 32 MPa and then tested under a 4-point bending loading regime. The results showed that using LECA as sand replacement in GC increased its compressive strength at all ages and all replacement ratios. Compared with the control GC mix, using 60% LECA increased the compressive strength by up to 44%, 39%, and 27%, respectively at 3, 7, and 28 days. The slabs test showed that partial or full replacement of GC sand adversely affected the shear resistance of concrete and caused premature failure of slabs. The slab strength and deflection capacities decreased by 9% and 30%, respectively when using rubber, and by 23% and 59%, respectively when using LECA, compared with control GC slab. The results indicated the applicability of GC mix with 60% LECA in structures subjected to axial loads. However, rubber would be the best lightweight material to recommend for resisting impact and flexural loads. [ABSTRACT FROM AUTHOR]

Nucleosomes are complexes of DNA and histone proteins that form the basis of eukaryotic chromatin. Eukaryotic histones are descended from Archaean homologs; however, how this occurred remains unclear. Our previous genetic analysis on the budding yeast nucleosome identified 26 histone residues conserved between S. cerevisiae and T. brucei; 15 that are lethal when mutated and 11 that are synthetically lethal with deletion of the FEN1 nuclease. These residues are partially conserved in nucleosomes of a variety of giant viruses, allowing us to follow the route by which they were established in the LECA (Last Eukaryote Common Ancestor). We analyzed yeast nucleosome genetic data to generate a model for the emergence of the eukaryotic nucleosome. In our model, histone H2B-H2A and H4-H3 doublets found in giant virus nucleosomes facilitated the formation of the acidic patch surface and nucleosome entry sites of the eukaryotic nucleosome, respectively. Splitting of the H2B-H2A doublet resulted in the H2A variant, H2A.Z., and subsequent splitting of the H4-H3 doublet led to a eukaryotic specific domain required for chromatin binding of H2A.Z. We propose that the LECA emerged when the newly-split H3 N-terminal horizontally acquired a common N-tail found in extinct pre-LECA lineages and some extant giant viruses. This hypothesis predicts that the emergence of the H3 variant CENP-A and establishment of CENP-A-dependent chromosome segregation occurred after the emergence of the LECA, implying that the root of all eukaryotes is assigned within Euglenida.

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The dichotomy that separates prokaryotic from eukaryotic cells runs deep. The transition from pro- to eukaryote evolution is poorly understood due to a lack of reliable intermediate forms and definitions regarding the nature of the first host that could no longer be considered a prokaryote, the first eukaryotic common ancestor, FECA. The last eukaryotic common ancestor, LECA, was a complex cell that united all traits characterising eukaryotic biology including a mitochondrion. The role of the endosymbiotic organelle in this radical transition towards complex life forms is, however, sometimes questioned. In particular the discovery of the asgard archaea has stimulated discussions regarding the pre-endosymbiotic complexity of FECA. Here we review differences and similarities among models that view eukaryotic traits as isolated coincidental events in asgard archaeal evolution or, on the contrary, as a result of and in response to endosymbiosis. Inspecting eukaryotic traits from the perspective of the endosymbiont uncovers that eukaryotic cell biology can be explained as having evolved as a solution to housing a semi-autonomous organelle and why the addition of another endosymbiont, the plastid, added no extra compartments. Mitochondria provided the selective pressures for the origin (and continued maintenance) of eukaryotic cell complexity. Moreover, they also provided the energetic benefit throughout eukaryogenesis for evolving thousands of gene families unique to eukaryotes. Hence, a synthesis of the current data lets us conclude that traits such as the Golgi apparatus, the nucleus, autophagosomes, and meiosis and sex evolved as a response to the selective pressures an endosymbiont imposes.

Punching shear is the most important problem in flat slabs, which usually requires strengthening for safety reasons. One of the most popular strengthening methods is the employment of shear reinforcement. Also, in order to reduce the self-weight of slabs, lightweight aggregate concrete as well as the bubble deck technology were used in this research. To study the influence of shear reinforcement type on lightweight aggregate voided slab behavior under punching shear, three slabs having the same geometrical and mechanical properties, with different shear reinforcement type (hook, inclined bar and stud) were cast and prepared for testing. As well as a control specimen with no shear reinforcement was used for comparison reason. The results showed that the inclined shear reinforcement has the most positive influence on slab behavior, between the three types of reinforcement that were adopted in the experimental work.

Abstract Background Eukaryotic gene expression is controlled by a number of RNA-binding proteins (RBP), such as the proteins from the Puf (Pumilio and FBF) superfamily (PufSF). These proteins bind to RNA via multiple Puf repeat domains, each of which specifically recognizes a single RNA base. Recently, three diversified PufSF proteins have been described in model organisms, each of which is responsible for the maturation of ribosomal RNA or the translational regulation of mRNAs; however, less is known about the role of these proteins across eukaryotic diversity. Results Here, we investigated the distribution and function of PufSF RBPs in the tree of eukaryotes. We determined that the following PufSF proteins are universally conserved across eukaryotes and can be broadly classified into three groups: (i) Nop9 orthologues, which participate in the nucleolar processing of immature 18S rRNA; (ii) ‘classical’ Pufs, which control the translation of mRNA; and (iii) PUM3 orthologues, which are involved in the maturation of 7S rRNA. In nearly all eukaryotes, the rRNA maturation proteins, Nop9 and PUM3, are retained as a single copy, while mRNA effectors (‘classical’ Pufs) underwent multiple lineage-specific expansions. We propose that the variation in number of ‘classical’ Pufs relates to the size of the transcriptome and thus the potential mRNA targets. We further distinguished full set of PufSF proteins in divergent metamonad Giardia intestinalis and initiated their cellular and biochemical characterization. Conclusions Our data suggest that the last eukaryotic common ancestor (LECA) already contained all three types of PufSF proteins and that ‘classical’ Pufs then underwent lineage-specific expansions.

The article analyzes contemporary research on early microbial evolution starting from LUCA (Last universal common ancestor) to the establishment of the two branches of the empire (superkingdom) Prokaryota – Archaea and Bacteria. Under discussion are the basic stages and driving forces of biochemical, physiological and biological evolution of acetogens and methanogens and the role of genetic divergency and natural selection for the creation of microbial diversity. An attempt was made for the representation of different views on the origin of the nucleus and other cellular components, connected to the evolution of the eukaryotic cell. [ABSTRACT FROM AUTHOR]

This study aims to examine the effect of high temperatures on lightweight geopolymer concrete (LWGC) and lightweight ordinary concrete (LWOC) made of natural pumice and lightweight expanded clay aggregate (LECA) with the addition of trapped air. To this end, a geopolymer concrete matrix has been synthesized by the alkali-activation of fly ash (FA) and granulated blast furnace slag (GBFS). The geopolymer concrete samples were cured for 24 h at a temperature of 80 °C. To study the properties of fresh concrete, slump and slump flow tests and unit weight were applied. The mechanical properties were also measured by the compressive strength, splitting tensile, flexural strength, and elastic modulus tests. High temperatures of 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, and 800 °C were applied on the geopolymer concrete samples to obtain the residual compressive strength. In general, pumice and LECA can be used as an alternative to the dolomite aggregate to produce LWGC and LWOC. The mixture F-50D50P-A achieved the lowest of unit weight of 1660 kg/m, a slump flow of 555 mm, and compressive strength of 32.9 MPa at 91-days. Lightweight geopolymer concrete containing 50 % fly ash and 50 % GBSF achieved the best compressive strength test results. The results showed a similarity in the behaviour of LWGC with LWOC under the influence of all the variables applied in this study.

Lightweight concrete (LWC) has been used successfully in building constructions for many years due to its physical properties and its lightweight with high thermal insulation and durability. Recently, this work was done on a new type of concrete: lightweight self-compacting concrete (LWSCC) that combines the feature of lightweight and self-compacting concrete simultaneously. In this study, light expanded clay aggregate (LECA) was used as coarse aggregate in (LWSCC) mixtures, using nano-silica as a partial replacement of cement with three percent (0.5, 0.75, and 1%) by mass of cement. They were tested to evaluate these values of fresh characteristics through slump flow time and diameter, L-box, and segregation tests. The results of the fresh concrete tests showed a decrease in the workability of the concrete in the mixtures containing nano-silica due to the increase in fine materials in the mixture. The effects of nano-silica on the hardened properties of (LWSCC) such as compressive strength, flexural strength, splitting tensile strength, oven-dry density, and scanning electron microscopy (SEM), have improved. The mixtures containing nano-silica were investigated and compared with the reference mixture, where the results of the tests showed a significant improvement in the mechanical properties by (17.35, 16.27, 11.73, and 3.82%) for each of the compressive strength, flexural strength, splitting tensile strength and oven dry density respectively. In the presence of nano-silica, the replacement percentage of 1% recorded the best results in all tests at 90 days of curing.

For many years, lightweight concretes (LWC) have been utilized successfully in the construction of buildings because of their low specific weight, high thermal insulation capacity, and sound insulation. The development that led to lightweight self-compacting concrete (LWSCC) is a significant step forward in recent years. These concrete chains self-compacting concrete's beneficial properties with lightweight concrete. The purpose of this experimental investigation is to determine how the internal sulfates attack effect fresh and hard properties of lightweight self-compacting concrete (LWSCC) made by using lightweight expanded clay aggregate (LECA) before and after the addition of 0.5 volume fraction (Vf) of steel fibers. In fine aggregate, several concrete mixes were cast in different SO3 percentages (0.34, 2, 4, and 6%). The fresh properties of LWSCC concrete were tested, such as (slump, sieve segregation resistance, and L-box test). The hard properties of LWSCC were (Compressive, splitting tensile strength, flexural strength, oven-dried density, and modules of elasticity). The results showed that the presence of SO3 in fine aggregate affects the properties of LWSCC. A significant decrease in fresh properties of LWSCC mixes with (2, 4, and 6%) of SO3 in fine aggregate. In addition, the mechanical properties (compressive St., splitting tensile St., flexural St., density, and modulus of elasticity) decreased as curing age increased, and SO3% increased. When sulfate percent rose from (0.34% to 2%, 4%, and 6%) in compressive St., the reduction was (16.53, 22.45, and 26.47%) at 120 days. Adding 0.5% Vf of steel fiber enhanced the mechanical properties of LWSCC.