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Titanium dioxide (TiO₂) has high opacity, high brightness and whiteness, owing to its high refractive index value. It is mainly used in the coating industry and continuous efforts have been made to replace some of the TiO₂ in paint with new pigments. This study aims to replace part of TiO₂ pigment with various percentages of BaSO₄, CaCO₃ and kaolin in styrene butyl acrylate-based paint formulations, without changing the properties of paints using only titanium dioxide.

To determine the optimum use rate of new pigment mixing, opacity, gloss, scrub resistance and weather resistance properties have been investigated in the water-based paint formulation. The morphological properties of these samples were examined by scanning electron microscopy analysis.

In the total color change (ΔE) measurements, it was observed that the sample coded 85Ti/15Ba produced extremely similar results to the situation when TiO₂ was used alone. It was seen that the best results were obtained when 85Ti/15Ba was used instead of TiO₂.

Comparison research on the impact of replacing TiO₂ with BaSO₄, CaCO₃ and kaolin on the performance characteristics of water-based styrene butyl acrylate-based paint formulations has not been done in the literature, according to the literature search.

The textile sector struggles with cotton stickiness from honeydew contamination. It hurts agriculture and marketability. This study aims to examine how bacterial enzymes could reduce honeydew-contaminated cotton adherence in textile businesses sustainably.

Enzyme was extracted from bacteria isolated from the fermented bamboo shoots “Lung siej”. The enzyme was tested for α-glucosidase using p-nitrophenyl-α-D-glucopyranoside as a substrate. Design of experiments determined enzyme activity temperature and reaction time. Laboratory-prepared artificial honeydew was added to ginning mill cotton to show honeydew contamination. After enzyme treatment, sticky cotton was tested for microscopic examination, ultraviolet (UV), Benedict’s, Elsner colorimetric, high volume instrument (HVI) and viscosity tests.

The bacterial isolate is characterized as Lysinibacillus sp. as confirmed by 16S rRNA gene sequencing. The enzyme extracted was identified as α-glucosidase. The ideal temperature and reaction time for enzymatic activity were 32 °C and 35 min, respectively, using central composite design. The microscopic examination, UV test, Benedict’s test, Elsner colorimetric test, HVI test and viscosity test showed that bacterial enzyme treatment reduced cotton fiber adherence.

Although few patents have examined the effect of yeast enzymes, to the best of the authors’ knowledge, a bacterial enzyme is investigated for the first time to reduce the adhesion of honeydew-contaminated cotton.

The use of continuous fiber-reinforced filaments improves the mechanical properties obtained with the fused filament fabrication (FFF) process. Yet, there is a lack of simulation tailored tools to assist in the design for additive manufacturing of continuous fiber composites. To build such models, a precise elastic model is required. As the porosity caused by interbead voids remains an important flaw of the process, this paper aims to build an elastic model integrating this aspect.

To study the amount of porosity, which could be a failure initiator, this study proposes a two step periodic homogenization method. The first step concerns the microscopic scale with a unit cell made of fiber and matrix. The second step is at the mesoscopic scale and combines the elastic material of the first step with the interbead voids. The void content has been set as a parameter of the model. The material models predicted with the periodic homogenization were compared with experimental results.

The comparison between periodic homogenization results and tensile test results shows a fair agreement between the experimental results and that of the numerical simulation, whatever the fibers’ orientations are. Moreover, a void content reduction has been observed by increasing the crossing angle from one layer to another. An empiric law giving the porosity according to this crossing angle was created. The model and the law can be further used for design evaluation and optimization of continuous fiber-reinforced FFF.

A new elastic model considering interbead voids and its variation with the crossing angle of the fibers has been built. It can be used in simulation tools to design high performance fused filament fabricated composite parts.

Military and unmanned aerial vehicles (UAV) applications like rocket motor casings, missile covers and ship hulls use components that are made of maraging steel. Maraging steel has properties that are superior to other metals, making it more suitable for the fabrication of such components. A grey relational analysis (GRA) that is based on the Taguchi method has been utilised in the current study to optimise a laser beam welding (LBW) process. Further aspects such as GRA's optimum ranges and percentage contributions were also estimated.

A Taguchi L16 orthogonal array is utilised to design and conduct the experiments. Laser power (LP), welding speed (WS) and focal position (FP) are the three parameters are chosen for the process of welding. The output responses are the upper width of the heat-affected zone (HAZup), the upper width of the fusion zone (FZup) and the depth of penetration (DOP). The effect of the above key parameters on the responses was examined using an analysis of variance (ANOVA).

The results of ANOVA reveal that the parameter that has the most influence on the overall grey relational grade (GRG) is the FP. Finally, metallographic characterisation and a microstructural analysis are conducted on the weld bead geometry to demarcate the zone of HAZ and fusion zone (FZ).

As the most important criteria for LBW of maraging steels is the provision of higher DOP, higher FZ width and lower heat-affected zone, the study intended to prove the applicability of GRA technique in solving multi-objective optimisation problems in applications like defence and unmanned systems.

To contribute to the identification of the parameters influencing the behavior of textile-reinforced concrete (TRC), the purpose of this paper is to investigate the flexural behavior of TRC-based plates under four-point bending notably designed in the context of sustainable development and the substitution of mortar components with natural and abundant materials.

An extensive experimental campaign was focused about two main parameters. The first one emphases the textile reinforcements, such as the number of layers, the nature and the textile mesh size. In the second step, the composition of the mortar matrix was explored through the use of dune sand as a substitute of the river one.

Test results in terms of load-displacement response and failure patterns were highlighted, discussed and confronted to literature ones. As key findings, an increase of the load-bearing capacity and ductility, comparable to the use of an industrially produced second textile layer was recorded with the use of dune sand in the mortar mix design. The designed ecofriendly samples with economic concerns denote the significance of obtained outcomes in this research study.

The novelty of the present work was to valorize the use of natural dune sand to design new TRC samples to respond to the environmental and economical requirements. The obtained values provide an improved textiles–matrix interface performance compared to classical TRC samples issued from the literature.

This paper aims to investigate the theoretical and practical links between digital twin (DT) application in heritage facilities management (HFM) from a life cycle management perspective and to signpost the future development directions of DT in HFM.

This state-of-the-art review was conducted using a systematic literature review method. Inclusive and exclusive criteria were identified and used to retrieve relevant literature from renowned literature databases. Shortlisted publications were analysed using the VOSviewer software and then critically reviewed to reveal the status quo of research in the subject area.

The review results show that DT has been mainly adopted to support decision-making on conservation approach and method selection, performance monitoring and prediction, maintenance strategies design and development, and energy evaluation and management. Although many researchers attempted to develop DT models for part of a heritage building at component or system level and test the models using real-life cases, their works were constrained by availability of empirical data. Furthermore, data capture approaches, data acquisition methods and modelling with multi-source data are found to be the existing challenges of DT application in HFM.

In a broader sense, this study contributes to the field of engineering, construction and architectural management by providing an overview of how DT has been applied to support management activities throughout the building life cycle. For the HFM practice, a DT-cum-heritage building information modelling (HBIM) framework was developed to illustrate how DT can be integrated with HBIM to facilitate future DT application in HFM. The overall implication of this study is that it reveals the potential of heritage DT in facilitating HFM in the urban development context.

Monocytes are a leukocytes’ subset that plays an important role in immunity. Protein kinase B (AKT) is involved in monocytes' survival, proliferation and differentiation. Using phorbol 12-myristate 13-acetate (PMA) as an inducer for cell line U937 differentiation into macrophage-like cells may be used as a model for cancer cell therapy or other biomedical research studies. The authors investigated the Akt1 signaling pathway's involvement with PMA as a differentiating agent and survival in the U937 cell line.

PMA was utilized to stimulate the differentiation of the U937 cell line into macrophage-like cells at a concentration of 10 nM. Akt1-phosphorylated Serine 473, Bad-phosphorylated Serine 136 and Caspase9-phosphorylated Serine 196 were tested by flow cytometry for the involvement of the Akt1 signaling pathway during differentiation in addition to the expression of CD14, CD206 and CD83. DNA cell cycle variation analysis was done using PI staining and cell viability and apoptosis detection using Annexin V and PI flow cytometry.

There was a decrease in phosphorylated Akt1 and Bad activation and an increase in Caspase9 activation, with an increase in surface markers CD14, CD206 and CD83 acquired by PMA-differentiated cells. DNA cell cycle analysis revealed cell accumulation in the G2/M phase and fewer cells in the S phase of PMA-induced U937. Apoptosis induction for Ly294002 or Wortmannin-inhibited cells and part of PMA-induced cells were detected.

These results may be used to create a model for biomedical research studies and advance the understanding of the mechanism involving differentiation of the U937 cell line.

Sports tourism was strongly affected by the COVID-19 pandemic, but there is no consensus on what sports tourism should look like in the post-pandemic period. This study explores the future of sports tourism in light of the COVID-19 pandemic and provides an alternative paradigm model.

Data were collected by interviewing sports tourism experts. Data analysis was based on the continuous comparison method during three stages of open, axial and selective coding.

The findings point to the complexity of the future sports tourism industry. Post-COVID-19 sports tourism strongly depends on environmental forces and targeted support, with strategies focused on tourists’ safety and security, digitalization of the industry, and new employment opportunities.

This study contributes to the body of knowledge on sports tourism by providing answers to the current challenges, threats and opportunities associated with the pandemic. The proposed paradigm model could be a guideline for sports tourism practitioners and policymakers to accelerate recovery from COVID-19 in a sustainable and resilient manner.

This study aims to optimize the preparation conditions and modify the nanofiltration (NF) membranes to prepare high-performance polysulfone/sulfonated polysulfone composite nanofiltration (PSF/SPSF-NF) membranes through interfacial polymerization.

Investigating the impacts of anhydrous piperazine (PIP) concentration, trimesoyl chloride (TMC) concentration and basement membrane type on NF membrane performance, the optimal membrane was prepared. In addition, nano-SiO₂ was added to the active separation layer to modify the NF membranes.

The comprehensive performance of PSF/SPSF-NF membranes was optimized when the concentration of PIP was 0.75 Wt.% and the concentration of TMC was 0.15 Wt.%, at which time the water flux was 66.1 L·m⁻²·h⁻¹ and the retention rate of Na₂SO₄ was 98.1%. The comprehensive performance of polysulfone/sulfonated polysulfone-SiO₂ nanofiltration (PSF/SPSF-SiO₂-NF) membranes was optimized when the blending ratio of nano-SiO₂ to PIP was 2:3, with a pure water flux of 81.9 L·m⁻²·h⁻¹ and a Na₂SO₄ retention rate of 95.9%. Compared to polysulfone nanofiltration (PSF-NF) membranes and PSF/SPSF-NF membranes, NF membranes with nano-SiO₂ increased the flux recovery rate by 22.9% and 8.7%.

PSF/SPSF-SiO2-NF membrane exhibits excellent antifouling properties.

There is currently no literature available on the preparation of NF membranes using polysulfone/sulfonated polysulfone (PSF/SPFS) as a substrate. This provides a method for modifying NF membranes, starting with the modification of the basement membrane and then modifying the active separation layer.

This research examines the association of physical development density, prevalence and types of microbes in colonized façade finishes of buildings in Enugu metropolis, Nigeria.

Survey and experimental research designs were adopted. A total of 383 buildings were investigated with samples collected from those with colonized façade finishes. The microbes were identified using the standard procedure for genomic sequencing with descriptive statistics, and the chi-square test used to analyse the data.

The results revealed a 64% prevalence of microbial colonization and a significant association between this and physical development density with 71.0% of the colonized buildings located in high-density neighbourhoods of the metropolis. The sequencing also showed 24 different microbes with Trichophyton tonsurans, Trichophyton mentagrophytes and Trichoderma harzianum species being the most common in the colonized façade finishes.

The research informs building professionals and owners of the specific microbes involved in the colonization of façade finishes of buildings in high-density urban areas. It also provides a clue about the nature of damages and defects associated with microbial colonization of building façades and the type of biocide additives required for the production of microbial-resistant façade finishes in the hot-humid tropical environment of Nigeria and beyond.

The study has shown that there is a significant relationship between the intensity of urban land use and microbial colonization of façade finishes of buildings. It also identified some new or less known microbes responsible for the biodeterioration of façade finishes and the effects this has on the buildings and public health in the hot-humid tropics of Enugu, Southeast Nigeria.