Plate Method Research Articles

Study on spring-back characteristics of magnesium alloy plate in multi-point forming

Abstract Multi-point forming (MPF) is an advanced method of plate forming with its characteristics of dieless, rapid, and flexible. In this paper, the springback of Magnesium alloy (Mg alloy) plates was researched under different geometrical conditions, mechanical properties, and constitutive models with the MPF method. The studies showed that the springback of Mg alloy plates reduced with the thickness of the plates, increased with curvature radius, and enlarged with the initial yield strength. Meanwhile, the simulated results indicated that the constitutive model had a significant influence on the springback of the Mg alloy plate forming.

Antibacterial and cytotoxicity properties of a polyherbal mouthwash containing Achyranthes aspera and Trachyspermum ammi against selected periodontal pathogens

BackgroundChlorhexidine (CHX) is considered as a gold standard for its antibacterial efficacy and substantivity in chemical plaque control. However, some adverse effects are associated with its prolonged use. Herbal medicines like Achyranthes aspera and Trachyspermum ammi have been used in many clinical conditions, and they appear to be a valuable substitute next to CHX in the management of periodontal diseases. ObjectiveThis in vitro study was designed to assess and compare the antibacterial potential and cytotoxic effects of novel polyherbal mouthwash containing A. aspera and T. ammi with 0.2% CHX mouthwash against Porphyromonas gingivalis, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans. MethodsEthanolic extracts of A. aspera and T. ammi were prepared by the Soxhlet apparatus method and were subjected to preliminary phytochemical screening. The individual plant extracts and the plant extract mixture (PEM) of A. aspera and T. ammi in the ratio of 1:1, 2:1, 1:2 (w/v) were assessed for minimum inhibitory concentration (resazurin microtitre assay) and minimum bactericidal concentration (spread plating method) against selected periodontal pathogens in comparison to CHX. The polyherbal mouthwash was assessed for zone of inhibition (well diffusion method) and cytotoxicity (MTT assay) on adult human gingival fibroblasts. All the experiments were performed in triplicate. ResultsThe antibacterial activity was evident in the PEMs, and polyherbal mouthwash against tested periodontal pathogens and was comparable to CHX. The cytotoxicity assay findings confirmed that polyherbal mouthwash exhibited 82.1% of surviving cells which proved good biocompatibility. ConclusionA. aspera and T. ammi based mouthwash possess comparable antibacterial activity against periodontal pathogens when compared to CHX.

Effect of salt concentration on osmotic potential in drying soils—Measurement and models

AbstractThe water potential in drying soils, comprising both matric potential and osmotic potential components, can be measured using the dew point method (DPM). By combining DPM data with retention curve data acquired from techniques such as the suction plate method or the simplified evaporation method (SEM), it becomes possible to determine the soil water retention curve across the entire moisture spectrum. However, as the latter methods only determine the matric potential, the osmotic potential component in DPM data must either be negligible or known so that osmotic and matric potential components can be separated. This study aims to critically analyse common approaches for calculating the osmotic potential. To achieve this, we measured the water retention properties of a silt loam, a sandy loam and a sand across the entire moisture range by combining SEM and DPM. By using almost salt‐free soil material, we characterized reference water retention curves with negligible osmotic potential components. The impact of salt on water potential was analysed by conditioning soils with MgCl2 solutions of different concentrations, drying them, and measuring the water potential at different water contents using the DPM. The resulting water potentials were compared to the reference potentials and differences were interpreted as the osmotic potential component. The DPM‐measured water potentials in drying soils can be significantly affected by osmotic potential, especially at higher matric potentials (low suctions). Two models accounting for ideal and one model accounting for non‐ideal electrolyte behaviour were used to compare osmotic potential predictions with measurements. At low to medium salt concentrations, all models performed fairly well. At high concentrations, only the model accounting for non‐ideal behaviour predicted the osmotic potential satisfactorily, whereas at very high concentrations, all models underestimated the impact of osmotic potential on water potential. This suggests that the surface properties of the soil matrix, such as the specific surface area and surface charges, may lead to a decrease in osmotic potential beyond what is expected in pure solutions.

Flexible and anisotropically conductive film by assembly of silicone rubber and cobalt-coated glass fiber composites

In this study, we prepared electromagnetic cobalt-coated glass fiber (Co@GF) composites via an electroless plating method. Subsequently, a conductive sandwich flexible film consisting of Co@GF composites and liquid silicone rubber (RTV-2) was successfully formed using the tape casting method at room temperature. Based on the perfect coating and excellent electrical conductivity of the Co@GF composites, the resultant RTV-2/Co@GF/RTV-2 sandwich flexible film showed a low volume resistivity of 0.264 Ω·cm and could stretch to 100% (of 4.40 Ω·cm) without obvious fracture. When a magnetic field was applied during the curing process, the electromagnetic Co@GF composites were aligned automatically in the RTV-2 matrix because of their ferromagnetic nature. The as-prepared film exhibited anisotropy in its electrical performance. The volume resistivity parallel to the magnetic field direction is approximately two times lower than that in the perpendicular direction. The maximum difference in the volume resistivity (ρ∥ = 0.768 Ω·cm and ρ⊥ = 1.549 Ω·cm) was obtained at a magnetic field intensity of 800 mT. In addition, a magnetic field intensity of 100 mT helps improve the electrical conductivity of the as-obtained sandwich film. The anisotropic RTV-2/Co@GF/RTV-2 sandwich flexible film is considered a promising flexible electronic sensor, where discrepant inductive sensitivity is required in orthogonal directions.

Microwave-assisted synthesis of some new 2-(substituted phenyl)-3-(thiazol-2-yl)imidazo[4,5-b]indoles of biological interest

In the present investigation, we have synthesized some new 2-(substituted phenyl)-3-(thiazol-2-yl) imidazo[4,5-b]indoles (1b-8b) of biological interest. In the last step of the synthesis, N-(substituted benzylidene)thiazole-2- amines (1a-8a) were reacted with isatin and ammonium acetate using silica gel as the solid support to yield the corresponding substituted thiazolyl imidazo indole derivatives (1b-8b). The reactions were carried out by two different techniques - conventional and microwave irradiation. The microwave irradiation method offers excellent yield, lesser reaction time, and eco-environmental friendly reaction. All the synthesized compounds showed anticancer (Dalton lymphoma ascites cell line and EAC cell line method) and antibacterial activity (cup plate method).. KEYWORDS :Thiazolyl imidazo indole, Microwave-assisted synthesis, Anticancer, Antibacterial.

Comparison of Dracocephalum Moldavica Essential Oil with Chlorhexidine on Cariogenic Bacteria.

Dental caries and periodontal disease are the most common oral problems. Chemical antibacterial agents often have side effects; thus, researchers have long been in search for organic and herbal products to prevent dental caries and periodontal disease. The present study has aimed to assess the effects of Dracocephalum moldavica essential oil on Streptococcus mutans, Streptococcus salivarius, Streptococcus sobrinus, and Lactobacillus acidophilus compared to Chlorhexidine (CHX). In this in vitro study, the plants were collected from Zanjan Province, Iran. Analysis of the essential oil was carried out by gas chromatography/mass chromatography. Micro-broth dilution and disc diffusion methods were used for assessment of the antimicrobial activity, and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated. The mean diameter of the growth inhibition zones in the well plate method for Dracocephalum moldavica showed that it had greater antimicrobial activity against Lactobacillus acidophilusthan others (p Value= 0.01). Furthermore, Dracocephalum moldavica had higher antimicrobial activity than CHX. The results of MIC and MBC showed that Dracocephalum moldavica had lower antibacterial activity than CHX. Dracocephalum moldavica essential oil demonstrated antibacterial properties against cariogenic bacteria. Given that other favorable properties of these essential oils are confirmed, they may be suitable for use as antibacterial agents in the formulation of oral healthcare products.

Total Plate Count of Germs on Pear Surface Swabs During Washing with Fruit Washing Soap

The surface of the fruit is the first contamination of microorganisms on fruit with varying types and amounts. As many as 20% of cases of food poisoning caused by Salmonella typhi were recorded as a result of the consumption of fresh ready-to-eat products such as fruits. Washing the fruits that will be consumed is a good step, so a fruit washing soap product is used that can clean the fruits from these bacteria. Nonionic surfactants are cleaning agents found in fruit washing soaps that can remove bacteria on surfaces. The purpose of this study was to determine the difference in the total plate number of germs on the surface of pears when washing with fruit washing soap. The research method used in this research is descriptive method. The population is 50 soaps taken from 5 shops in the Harapan Baru market in Samarinda with different soap brands. The sample taken is 10% of the total population, namely 5 soaps. The sampling technique used purposive sampling. The study was carried out in July 2022. The method of examination used the examination of the TPC (Total Plate Count) with the pour plate method using PCA (Plate Count Agar) media. The data analysis used is univariate analysis which aims to explain the characteristics of each research variable by looking at the frequency distribution. The results showed that the number of bacteria before washing with fruit washing soap ranged from 4.4 x 100 CFU/cm2 to 1.4 x 101 CFU/cm2. Meanwhile, the number of bacteria after washing with fruit washing soap ranged from 0.4 x 100 CFU/cm2 to 3.4 x 100 CFU/cm2. The conclusion of this study is that there are differences in the number of total bacterial plate count on the surface of pears when washing with fruit washing soap.

Enhanced performance of Lithium–Sulfur cells via novel nano-sized iron-plated sulfur composites

Lithium–sulfur cells are promising energy-storage systems because of their high energy density and the desirable electrochemical utilization rates of cost-effective sulfur cathodes. However, the commercialization of high-performance lithium–sulfur cells, which are characterized by a high discharge capacity and cyclic stability, necessitates simultaneous optimization of both the cell-fabrication parameters and cell-performance values. Here, we introduce a novel iron-plated sulfur composite featuring nano-sized conductive iron plating applied to micro-sized insulating sulfur particles through an innovative electroless-iron plating method. The iron-plated sulfur composite facilitates the realization of a lean-electrolyte lithium–sulfur cell at a low electrolyte-to-sulfur ratio of 5 μL mg−1, enabling high-loading sulfur cathodes (sulfur loadings of 10–14 mg cm−2) to attain a reversible discharge capacity (945–1033 mAh g−1) and a cycle life of 400 cycles. These well-controlled cell-fabrication parameters, coupled with the high cell performance, result in improved performance metrics, such as high areal capacity (10–13 mAh cm−2), improved energy density (22–28 mWh cm−2), and a low electrolyte-to-capacity ratio (4.8 μL mAh−1). These advancements are attributable to the incorporation of plated nano-sized iron, which endows the cathode with rapid electron/ion transfer, robust polysulfide retention, and heightened electrocatalysis capabilities for conversion-type battery chemistry.

Characterization of Bacterial Population Associated with Deterioration of Stored Kinnow Fruits (Citrus nobilis x Citrus deliciosa)

Fresh and spoiled Kinnow fruits were collected from local market in Kharar, Punjab, India to isolate and identify the microbial factors that causes deterioration of stored Kinnow (Citrus reticulata), as well as to study the impact of temperature to fruits at different storage conditions. Several microorganisms, including bacteria and fungus, may thrive in ideal condition present within the fruits. Using the pour plate method, the infected portion of the fruit was utilised to isolate the bacteria by serial dilution. Healthy colonies were selected and sub-cultured. Two types of bacteria have been isolated. Following morphological analysis and biochemical characterization, Staphylococcus spp. and Escherichia coli were determined to be the responsible organism.

Prevalence of Clostridium Perfringens Spores in Selected Regions of Saudi Arabia

The prevalence of Clostridium perfringens spores in the environment is crucial for the pathogenesis of this bacterium because these dormant spores, upon contact with a suitable host, can return to active growth to cause disease.We evaluated the prevalence of C. perfringens spores in the Hail and Qassim regions of Saudi Arabia.Methods: A plating method was used to identify C. perfringens. PCR analyses and DNA sequencing were performed for genotypic characterization of the newly isolated C. perfringens.25 of 300 collected samples were identified as C. perfringens by selecting black colonies on selective media and monitoring b-hemolysis on blood agar plate. PCR analyses showed that all 25 isolates carry a-toxin gene (plc), but not the enterotoxin gene (cpe), further confirming that these isolates are indeed cpe-negative. Genome sequencing found that Saudi isolates are genotypically similar to the American and European isolates; no homologues of toxinotyping genes encoding b-, i-, e- and NetB-toxin were detected in 22 Saudi isolates, with the exception of 3 isolates that carry only e-toxin gene etx. Collectively, our findings suggest that C. perfringens are highly prevalent in the Hail and Qassim environment, with 22 (88%) of 25 isolates are type A and remaining 3 (12%) are type D.

Unilateral buckling of thin plates by complementarity eigenvalue analyses

In this work, the analysis by the finite element method of thin plates subjected to buckling in the presence of unilateral punctual obstacles, that is, supports that allow the plate to move in one direction but prevent the motion in the opposite direction, is addressed. An appropriate algorithm based on the solution of a semi-smooth system of equations, that results from the formulation of the unilateral buckling problem as a complementarity eigenvalue problem, is used. Rectangular and square plates are analysed under various membrane loadings, including compression and shear. The conformal Bogner–Fox–Schmit (BFS) finite element is employed to compute the bifurcation loads and the corresponding instability modes in scenarios with and without unilateral obstacles. For each plate and type of loading, the six lowest bifurcation loads and corresponding modes are computed for different levels of mesh refinement. The results confirm that the convergence of bifurcation loads obtained using the BFS element is monotonically decreasing as the mesh is refined. It is also confirmed that, when unilateral obstacles are present, the lowest bifurcation load, known as the critical load, can never be lower than the one of the homologous problem without unilateral obstacles.

Assessment of mrkD and T1 fim Genes of K. pneumoniae and Their Association with Biofilm Formation in Community-Acquired Infections

Background: Klebsiella pneumoniae is a pathogenic bacteria that can form biofilms on abiotic and biotic surfaces. The constraints of the therapeutic choices against K. pneumoniae arise from its innate capacity to develop biofilm and harboring determinants of multidrug resistance. Objective: The current study aimed to assess the prevalence of some fimbrial genes (type 1 and type 3) of K. pneumoniae strains in community-acquired infections obtained from various clinical sources on their ability to produce biofilm. Methods: A total of 256 samples (106 male and 150 females) were taken from various clinical sources including Urine, wound swabs, sputum, burn swabs, bronchial wash, diabetic foot ulcer, and higher vaginal swabs) from outpatients in Kirkuk City hospitals. The isolates were identified on the Blood agar, MacConkey agar and Eosin Methylene Blue agar based on the cultural, morphological, in addition to biochemical assays, and confirmed using the automated VITEK 2 system. The Microtiter plate (MTP) method was employed to detect Biofilm formation. Subsequently, a polymerase chain reaction was performed to determine the presence of the T1 fim and mrkD genes. Result: Out of 256 only 38 (14.8%) isolates belonged to Klebsiella pneumoniae. Of all isolates, 38(100%) were biofilm producers. The PCR results revealed that all 38 isolates showed positive (100%) for T1 fim and 37 isolates (97.4%) for mrkD.

Molecular Evaluation of Aminoglycoside Resistance and Biofilm Formation Potential in Escherichia coli Isolates Collected from Hospitalized Patients

Background: Resistance to antibiotics and the ability to develop biofilms, two main virulence determinants of Escherichia coli, play a crucial role in the persistence of infections. Objectives: The aim of this study was to evaluate aminoglycoside resistance and biofilm formation potential in E. coli isolates collected from hospitalized patients in the Southwest of Iran. Methods: A total of 70 E. coli clinical isolates from different specimens were collected from Ahvaz teaching hospitals affiliated with Ahvaz Jundishapur University of Medical Sciences. All the isolates were identified as E. coli using conventional microbiological tests. Susceptibility to antibiotics was determined using the Kirby–Bauer disk diffusion method. Biofilm formation was assessed using the microtiter plate method. Finally, PCR was conducted to detect virulence gene determinants, including fimbrial genes, aminoglycoside modifying enzymes (AMEs), and 16S rRNA methylase (RMTase) genes. Results: Among aminoglycoside antibiotics, E. coli isolates showed the highest and lowest resistance rates to tobramycin (TOB; 51.4%) and gentamicin (GEN; 24.2%), respectively. Simultaneous resistance to GEN, amikacin, and TOB was observed in 28.5% of the isolates, representing the most common antibiotic resistance pattern. The prevalence of strong biofilm producers was higher in the extensively drug-resistant (XDR) phenotype group compared to the multiple drug-resistant (MDR) group (76.1% vs. 23.8%). Among the 36 isolates resistant to at least one of the aminoglycoside antibiotics, 36.1% had AME-related genes, either alone or in various combinations. Most isolates harboring AME genes were also positive for the presence of biofilm-related genes, including ecpA and fimA. Conclusions: The most frequent AME-related genes were ant(2”)-Ia and aph(3’)-Ia, followed by aac(3’)-IIa. The findings of the present study provide probable evidence that GEN is an effective aminoglycoside against biofilm-producing and antibiotic-resistant E. coli isolates.

Synthesis of Graphene@C3N4-Cu Beads Nanocomposites and their Antimicrobial Efficacy Against Drug-Resistant Bacteria and Fungi.

Increased intake of drugs worldwide and the subsequent advent of resistance to existing antibiotics have globally threatened health organizations. To combat the problem of these drug-resistant infections, as an alternative approach, graphene (GN)-related nanomaterials have attracted significant interest because of their effective anti-microbial potential. The present study shows the synthesis and characterization of nanocomposite of GN with carbon nitride viz. g- C3N4, g-C3N4-Cu, and GN@g-C3N4-Cu. Further, we investigated the anti-microbial potential of these nanocomposites against strains of Gram-negative and Gram-positive bacteria, viz., a multidrug- resistant strain of Pseudomonas aeruginosa (MDRPA), a methicillin-resistant strain of Staphylococcus aureus ATCC33593 (MRSA), and an azole-sensitive fungal strain (Candida albicans ATCC14053). The morphological characterization of GN@g-C3N4-Cu nanocomposite was executed by scanning electron microscopy, whereas the elemental analysis and their distribution were studied by energy-dispersive X-ray spectroscopy and elemental mapping methods. Furthermore, the anti-microbial and antibiofilm efficacies of g-C3N4, g-C3N4-Cu, and GN@g-C3N4-Cu nanocomposites were evaluated by disc diffusion, two-fold serial micro broth dilution, and 96 well microtiter plate methods. The ternary g-C3N4-Cu@GN, apart from the structures of g-C3N4-Cu, showed big sheets of GN. The observance of C, N, O, and Cu in the elemental analysis, as well as their uniform distribution in the mapping, indicated the successful fabrication of g-C3N4-Cu@GN. GN@g-C3N4-Cu followed by g-C3N4-Cu and (g-C3N4) exhibited significantly higher antimicrobial activity (zone of inhibition from 14.33 to 49.33 mm) against both the drug-resistant bacterial strains and azole-sensitive C. albicans. MICs of nanocomposites ranged from 32 -256 μg/ml against the tested strains. Whereas all three nanocomposites at sub-MICs (0.25 A- and 0.5 A- MICs) showed concentration- dependent inhibition of biofilm formation in MDRPA, MRSA, and C. albicans by allowing 11.35% to 32.59% biofilm formation. Our study highlights the enhanced efficiency of GN@g-C3N4-Cu nanocomposites as potential anti-microbial and antibiofilm agents to overcome the challenges of multi-drug-resistant bacteria and azole-sensitive fungi. Such kind of nanocomposites could be used to prevent nosocomial infections if coated on medical devices and food manufacturing instruments.

Pilot study on the feasibility of shape memory alloy implantation for Vancouver type B1 periprosthetic femoral fractures in a canine model: a step toward advancing treatment modalities

BackgroundCerclage wiring is commonly used for treating fractures; however, it has several limitations, including mechanical weakness, decreased blood circulation, and technical complexity. In this study, we developed an implant using a shape memory alloy (SMA) and tested its efficacy in treating Vancouver type B1 (VB1) periprosthetic femoral fractures (PFFs) in a canine model.MethodsThe mid-diaphyseal fracture models underwent reduction via the SMA plate (SMA group) or the cerclage cable plate (cable group) method in randomly selected pelvic limbs. An intraoperative evaluation was conducted to assess the surgical time and difficulty related to implant fitting. Clinical assessments, radiography, microcomputed tomography (micro-CT), histological analysis, positron emission tomography (PET)/CT, and galvanic corrosion analysis were conducted for 52 weeks to evaluate bone healing and blood perfusion.ResultsThe results for bone healing and blood perfusion were not significantly different between the groups (p > 0.05). In addition, no evidence of galvanic corrosion was present in any of the implants. However, the median surgical time was 75 min (range, 53–82 min) for the SMA group and 126 min (range, 120–171 min) for the cable group, which was a statistically significant difference (p = 0.0286).ConclusionsThis study assessed the ability of a newly developed shape memory alloy (SMA) to treat VB1 periprosthetic femoral fractures (PFFs) in canines for over a 52-week period and revealed outcomes comparable to those of traditional methods in terms of bone healing and mechanical stability. Despite the lower surgical complexity and potential time-saving benefits of this treatment, further research is needed to confirm its efficacy.

Characterization of Clonal Groups of Antibiotic-Resistant Biofilm-Forming Staphylococcus aureus Strains Isolated from Patients with Urinary Tract Infections in Isfahan, Iran

Background: Over the past decades, the role of biofilm-forming Staphylococcus aureus strains in urinary tract infections (UTIs) has garnered significant attention. Objectives: This study aimed to determine the epidemiological characteristics and diversity of S. aureus strains isolated from patients with UTIs in Isfahan, Iran, in 2017, with regard to their antimicrobial resistance, biofilm formation, and phylogenetic profiles. Additionally, the study investigated potential relationships among these factors statistically to develop efficient control and treatment approaches. Methods: All patients with symptomatic UTIs who had positive urine cultures for S. aureus during the study period at the laboratory of a referral hospital in Isfahan were included. All isolates were identified using specific primers for the nucA gene. Their biofilm formation capacity was evaluated using a combination of the microtiter plate and Congo-red agar methods. Antibiotic susceptibility testing was performed using the disk diffusion method. The presence of genes involved in biofilm formation and resistance to cefoxitin, aminoglycosides, and fluoroquinolones was detected using polymerase chain reaction (PCR). Staphylococcal cassette chromosome mec (SCCmec) typing, agr typing, and phene plate (PhP) typing were employed to investigate the diversity of collected strains. Results: Results showed that 19%, 57%, and 24% of confirmed S. aureus strains were strong, intermediate, and non-biofilm formers, respectively. The highest rate of resistance was against nalidixic acid (77%), followed by streptomycin (73%). The icaD and icaA genes had the highest frequency among biofilm-producing strains. gyrA (44%) and grlA (35%) were the most frequent genes among fluoroquinolone-resistant strains, while aph(3′)-IIIa was the most prevalent aminoglycoside-modifying enzyme gene. The majority of bacterial strains harbored SCCmec type III and agr type I. PhP typing of strains revealed the presence of 8 common types (CTs) and 14 single types (STs), with CT2 being the dominant type. Conclusions: The present investigation revealed various biofilm production capacities, antimicrobial resistance profiles, and clonal lineages in S. aureus isolated from patients with UTIs. These findings provide further insights into the epidemiology and pathogenicity of S. aureus strains in Iran, thereby improving the quality of surveillance and therapeutic protocols.

Isolation and Identification of Swan (Cygnus olor) Digestive Tract Cellulothic Bacteria to Support Fiber Degradation

Cellulolytic bacteria are bacteria that produce cellulase enzymes capable of degrading cellulose substrates. This study aimed to isolate and identify as well as measure the cellulase enzyme activity of cellulolytic bacteria isolated from the digestive tract of swans (Cygnus olor) in Mataram. The bacteria were isolated using de Man Rogosa Sharpe (MRS) selective media with the spread plate method. Then, the extracellular enzyme activity test was conducted by growing selected pure isolates on 1% Carboxy Methyl Cellulose (CMC 1%) media, followed by pouring 0.1% congo red solution and rinsing with 1M NaCl solution to determine cellulolytic activity (cellulolytic potential indicated by the appearance of a clear zone around the colony) and measuring the cellulolytic index. The bacterial isolation results obtained 4 isolates with the potential to support fiber degradation in animal feed. The highest cellulolytic index was produced by the isolate coded S1, reaching 34.5 mm, while the lowest cellulolytic index was produced by 2 isolates coded J21 and I2, reaching 18.8 mm.

Harnessing Natural Pozzolan for Sustainable Heating and Cooling: Thermal Performance and Building Efficiency in Moroccan Climates

The need to construct environmentally friendly buildings to meet current environmental and ecological standards is urgent. This study introduces a new multi-layer construction material with two outer layers of ordinary mortar and an inner layer of a pozzolane-limes composite to meet this need. The thermal efficiency of this material in building construction is investigated using TRNSYS18 simulations for two distinct climatic zones in Morocco, with a particular focus on its impact on heating dynamics. The primary objective is to evaluate the thermal performance of multi-layered pozzolanic materials, for which mortar samples are meticulously prepared as a reference in the two different climatic zones (Azilal and Errachidia). Using the asymmetric hot plate method under both stable and transient conditions, the authors conduct thermal characterization experiments. The results underscore the improvement in thermal performance made possible by the incorporation of pozzolan as an aggregate in the multi-layer material compared to ordinary mortar. Specifically, thermal conductivity improves significantly, from 0.735 W m−1 K−1 for ordinary mortar to 0.4 W m−1 K−1 for multi-layered pozzolanic materials, representing a 46% mass gain. Additionally, effusivity decreases from 730 to 604 J m−2 K−1 s−1/2, while diffusivity decreases from 3.78 to 2.23 × 10−7 m2 s−1, further attesting to the material’s thermal efficacy. TRNSYS18 simulations corroborate the viability of using multi-layered materials as building envelopes, revealing potential annual heating gains of 25% in Azilal and 5% in Errachidia. These findings underscore the promising prospects of integrating these materials into sustainable construction practices.

Model Modification of the Soil–Water Characteristic Curve of Unsaturated Weak Expansive Soil

This study evaluates the impact of compaction on the soil–water characteristic curve of unsaturated remodeled weakly expansive soils by assessing changes in soil pore structure resulting from variations in compaction. The remodeled weakly expansive soil in the Xinjiang Hami area is taken as the research subject to investigate how compaction affects microscopic pore structure using mercury intrusion testing. Subsequently, mercury intrusion porosimetry is employed to examine pore structure and distribution patterns at different dry densities. Based on the capillary principle and experimental methods (filter paper method and pressure plate method test), modified soil–water characteristic curves are obtained by fitting them with a three-parameter model law. The results indicate that higher dry density leads to an increased air intake value and significantly reduces the total volume of large pores within samples. Both the Fredlund and Xing model and the three-parameter model effectively capture the influence of initial dry density on the development pattern of the soil–water characteristic curve.

Chitosan nanoparticles, Rose Bengal-chitosan activated photodynamic therapy as final irrigant on pushout bond strength, smear layer removal efficacy and antibacterial effectiveness against E.faecalis

AimImpact of final root canal disinfectants diode laser (DL), Rose Bengal photosensitizer (RBP), Chitosan Nanoparticles (CNPs), and CNPs modified RBP on Enterococcus faecalis (E.faecalis) survival rate, smear layer (SL) removal efficacy and push out bond strength (PBS) of resin sealer to the radicular dentin. Material and methodSingle rooted seventy-five human mandibular premolar teeth were sectioned at a level of cementoenamel (CEJ) and root canal treatment was performed using a ProTaper rotary instrument. To assess the antibacterial efficiency E.faecalis inoculation was performed using a pour plate method. The samples were arbitrarily allocated into five groups based on the final disinfectant received (n = 15) Group-1 (NaOCl+17 % EDTA), Group-2 (NaOCl+DL), Group-3 (NaOCl+CNPs), Group-4 (NaOCl+RBP activated by DL) and Group-5 (NaOCl+CNPs-RBP activated by DL). SEM analysis for SL removal was performed on five specimens from each group. Root canal obturation and sectioning were performed at cervical, middle, and apical levels. PBS and failure mode were analyzed using a universal testing machine (UTM) and stereomicroscope respectively. The data was subjected to analysis using one-way analysis of variance (ANOVA) and Tukey's post hoc test. ResultGroup 1 (NaOCl+17 % EDTA) (0.36 ± 0.01 CFU/mL) unveiled the maximum survival rate of tested bacteria. However, Group 5 (NaOCl+CNPs-RBP activated by DL) (0.11 ± 0.01 CFU/mL) displayed minimum survival of E.faecalis. The highest SL removal (1.44 ± 0.11) and bond integrity scores (12.23 ± 0.24 MPa) were recorded in the coronal section of Group 5 (NaOCl+ CNPs-RBP activated by DL) treated roots. However, the lowest removal of SL (3.15 ± 1.09) and PBS (7.24 ± 0.09 MPa) were recorded in Group 4 (NaOCl+RBP activated by DL) treated canals. CONCLUSIONCNPs-RBP activated by DL as the final irrigant provided satisfactory antibacterial activity, SL removal, and bond strength outcomes compared to other tested groups.