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1.
Curr Issues Mol Biol ; 46(6): 5894-5908, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38921023

ABSTRACT

Lung cancer (LC) represents the leading cause of global cancer deaths, with cigarette smoking being considered a major risk factor. Nicotine is a major hazardous compound in cigarette smoke (CS), which stimulates LC progression and non-small cell lung cancer (NSCLC) specifically through activation of the nicotinic acetylcholine receptor (α7nAChR)-mediated cell-signaling pathways and molecular genes involved in proliferation, angiogenesis, and metastasis. Chalcones (CHs) and their derivatives are intermediate plant metabolites involved in flavonol biosynthesis. Isoliquiritigenin (ILTG), licochalcone A-E (LicoA-E), and echinatin (ECH) are the most common natural CHs isolated from the root of Glycyrrhiza (also known as licorice). In vitro and/or vivo experiments have shown that licorice CHs treatment exhibits a range of pharmacological effects, including antioxidant, anti-inflammatory, and anticancer effects. Despite advances in NSCLC treatment, the mechanisms of licorice CHs in nicotine-induced NSCLC treatment remain unknown. Therefore, the aim of this paper is to review experimental studies through the PubMed/Medline database that reveal the effects of licorice CHs and their potential mechanisms in nicotine-induced NSCLC treatment.

2.
Heliyon ; 10(11): e31930, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38845968

ABSTRACT

Adult obesity has remained a key health concern globally. Theory-based social marketing interventions are considered effective for improving dietary and physical activity (PA) behaviours. However, their application in universities is not yet established. This review aimed to identify social marketing strategies targeting healthy eating and/or PA behaviours of young adult university students and outline the intervention effectiveness. Literature search, screening, and data extraction followed the Joanna Briggs Institute (JBI) methodology for scoping reviews. PubMed/Medline and Scopus databases were searched for intervention and exploratory studies published between January 1, 2000, and September 20, 2023. Twelve articles were selected based on the eligibility criteria. Although different in study design, all studies reported improved healthy eating-related outcomes, while three showed improved PA-related outcomes. One study incorporated all six of the social marketing benchmarks, but the majority identified two. Most studies focused on behavioural objective, formative research, and marketing mix in their intervention design. Four studies incorporated behaviour change theories in development of the social marketing campaigns. Social marketing using social media could be a significant approach for improving healthy eating and PA in young adult university students when behavioural change theories and all social marketing benchmarks are adopted. More generalizable longer-term investigation into the effectiveness of this approach in university young adults is needed to tackle adult obesity related health issues.

3.
Materials (Basel) ; 17(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38730768

ABSTRACT

A promising method for additive manufacturing that makes it possible to produce intricate and personalized parts is selective laser melting (SLM). However, the mechanical properties of as-corroded SLM parts are still areas of concern. This research investigates the mechanical behavior of SLM parts that are exposed to a saline environment containing a 3.5% NaCl solution for varying lengths of time. The exposure times chosen for this study were 10 days, 20 days, and 30 days. The results reveal that the tensile strength of the parts is significantly affected by the duration of exposure. Additionally, the study also examined the influence of porosity on the corrosion behavior of the parts. The analysis included studying the mass loss of the parts over time, and a regression analysis was conducted to analyze the relationship between exposure time and mass loss. In addition, the utilization of scanning electron microscopy (SEM) and X-ray photo spectroscopy (XPS) techniques yielded valuable insights into the fundamental mechanisms accountable for the observed corrosion and mechanical behavior. It was found that the presence of corrosion products (i.e., oxide layer) and pitting contributed to the degradation of the SLM parts in the saline environment. This research emphasizes the importance of considering part thickness in the design of SLM components for corrosive environments and provides insights for enhancing their performance and durability.

4.
Microb Cell Fact ; 23(1): 150, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38790055

ABSTRACT

BACKGROUND: Azo dyes represent a common textile dye preferred for its high stability on fabrics in various harsh conditions. Although these dyes pose high-risk levels for all biological forms, fungal laccase is known as a green catalyst for its ability to oxidize numerous dyes. METHODS: Trichoderma isolates were identified and tested for laccase production. Laccase production was optimized using Plackett-Burman Design. Laccase molecular weight and the kinetic properties of the enzyme, including Km and Vmax, pH, temperature, and ionic strength, were detected. Azo dye removal efficiency by laccase enzyme was detected for Congo red, methylene blue, and methyl orange. RESULTS: Eight out of nine Trichoderma isolates were laccase producers. Laccase production efficiency was optimized by the superior strain T. harzianum PP389612, increasing production from 1.6 to 2.89 U/ml. In SDS-PAGE, purified laccases appear as a single protein band with a molecular weight of 41.00 kDa. Km and Vmax values were 146.12 µmol guaiacol and 3.82 µmol guaiacol/min. Its activity was stable in the pH range of 5-7, with an optimum temperature range of 40 to 50 °C, optimum ionic strength of 50 mM NaCl, and thermostability properties up to 90 °C. The decolorization efficiency of laccase was increased by increasing the time and reached its maximum after 72 h. The highest efficiency was achieved in Congo red decolorization, which reached 99% after 72 h, followed by methylene blue at 72%, while methyl orange decolorization efficiency was 68.5%. CONCLUSION: Trichoderma laccase can be used as an effective natural bio-agent for dye removal because it is stable and removes colors very well.


Subject(s)
Azo Compounds , Coloring Agents , Laccase , Temperature , Laccase/metabolism , Laccase/chemistry , Laccase/isolation & purification , Azo Compounds/metabolism , Coloring Agents/metabolism , Coloring Agents/chemistry , Kinetics , Hydrogen-Ion Concentration , Congo Red/metabolism , Osmolar Concentration , Hypocreales/enzymology , Hypocreales/metabolism , Biodegradation, Environmental , Fungal Proteins/metabolism , Fungal Proteins/chemistry , Fungal Proteins/isolation & purification
5.
Vet World ; 17(4): 842-847, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38798290

ABSTRACT

Background and Aim: Query fever (Q fever) is an endemic zoonotic disease and ruminants are considered to be the primary source of infection in humans. It is caused by Coxiella burnetii which is an obligate intracellular bacterial pathogen with a worldwide distribution. This study estimated the prevalence of Q fever in livestock with a history of abortion in Makkah Province, Saudi Arabia. Material and Methods: Sera from 341 camels, 326 sheep, and 121 goats of either sex from various locations (Makkah, Jeddah, AL-Taif, AL-Qunfudah, AL-Laith, and AL-Kamil) were examined using a Q fever indirect enzyme-linked immunosorbent assay. Results: Among the 788 serum samples, 356 animals had anti-Coxiella burnetii immunoglobulin G antibodies with an overall seroprevalence of 45.4%. Significant differences were observed in seroprevalence between species and locations. Camels had the highest percentage of Q fever-positive sera, with a prevalence of 50.4%, followed by goats (44.6%) and sheep (36.8%), with a high significant difference between animals (p = 0.000). The prevalence was significantly higher in Makkah (65.4%) than in Jeddah (28.8%). Conclusion: C. burnetii infection is prevalent in agricultural animals, especially camels maintained at livestock farms in Makkah province. Therefore, these animals considered as the main source of Q fever infections in Saudi Arabia, which is also a reason for the abortion in these animals. Therefore, there is an urgent need for further studies on Q fever infection with interventional approaches for prevention and control.

6.
Medicine (Baltimore) ; 103(19): e38099, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38728477

ABSTRACT

Patients with irritable bowel syndrome (IBS) experience not only a detrimental impact on their physical health but also a significant influence on their psychological well-being. This study aimed to assess the prevalence of IBS among university students, investigating the sociodemographic and lifestyle factors influencing its onset. Furthermore, it explored the potential impact of psychological factors such as depression, anxiety, and overall well-being on the prevalence of IBS. A cross-sectional analytical study was conducted at Saudi Arabian universities in November and December 2023. To collect data, an anonymous, validated, predesigned questionnaire was used. The diagnosis of IBS was carried out using the validated Arabic version of the Rome IV questionnaire. We used the Arabic version of the World Health Organization Well-being Index to assess the participants' well-being. We used the Arabic version of the Hospital Anxiety and Depression Scale (HADS) to identify people who show clinically significant symptoms of anxiety and depression. Our study included a total of 379 university students, 46.7% were female 86.0% of participants resided in urban areas, and 7.2% had been previously diagnosed with IBS. The prevalence of IBS among participants was found to be 31.9%. We observed a significant association between marital status and IBS (χ2 = 3.95, P = .047). Furthermore, the highest prevalence of IBS was observed among students majoring in literary and scientific disciplines (χ2 = 0.952, P = .049). Individuals with IBS demonstrate a significantly higher prevalence of anxiety (71.90% vs 41.09%, P < .001) and depression (64.46% vs 42.64%, P < .001) compared to those without IBS. Furthermore, people with IBS had a slightly higher prevalence of poor well-being (38.84%) compared to those without IBS (33.72%), but this association was not statistically significant. In multivariate analysis, having a family history of IBS [OR = 1.75 (95% CI, 1.06-2.87), P = .029] having borderline anxiety [OR = 7.58, 95% CI (2.12-27.06), P = .012] and anxiety [OR = 16.07, 95% CI (4.57-56.52), P < .001], and depression [OR = 2.97, 95% CI (1.13-7.83), P = .010] were the main significant predictors of IBS among university students. The high prevalence of IBS among university students was associated with a family history of IBS as well as depression and anxiety. Increasing awareness, multidisciplinary support, and access to mental health services is required to ensure university students' well-being.


Subject(s)
Anxiety , Depression , Irritable Bowel Syndrome , Students , Humans , Saudi Arabia/epidemiology , Irritable Bowel Syndrome/epidemiology , Irritable Bowel Syndrome/psychology , Female , Male , Students/psychology , Students/statistics & numerical data , Cross-Sectional Studies , Prevalence , Universities , Young Adult , Adult , Depression/epidemiology , Depression/psychology , Anxiety/epidemiology , Anxiety/psychology , Surveys and Questionnaires , Adolescent
7.
Plants (Basel) ; 13(7)2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38611574

ABSTRACT

Cancers of the reproductive organs, including prostate, bladder, ovarian, and cervical cancers, are considered the most common causes of death in both sexes worldwide. The genus Vaccinium L. (Ericaceae) comprises fleshy berry crop species, including cranberries, blueberries, lingonberries, bilberries, and bog bilberries, and are widely distributed in many countries. Flavonols, anthocyanins (ACNs), proanthocyanidins (PACs), and phenolic acids are the most bioactive compounds naturally found in Vaccinium berries and have been extensively used as anticancer agents. However, it remains uncertain whether Vaccinium bioactives have a therapeutic role in reproductive cancers (RCs), and how these bioactives could be effective in modulating RC-related signalling pathways/molecular genes. Therefore, this article aims to review existing evidence in the PubMed/MEDLINE database on Vaccinium berries' major bioactive compounds in RC treatment and unravel the mechanisms underlying this process.

8.
BMC Microbiol ; 24(1): 140, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38658810

ABSTRACT

Kojic acid is a wonderful fungal secondary metabolite that has several applications in the food, medical, and agriculture sectors. Many human diseases become resistant to normal antibiotics and normal treatments. We need to search for alternative treatment sources and understand their mode of action. Aspergillus flavus ASU45 (OL314748) was isolated from the caraway rhizosphere as a non-aflatoxin producer and identified genetically using 18S rRNA gene sequencing. After applying the Box-Behnken statistical design to maximize KA production, the production raised from 39.96 to 81.59 g/l utilizing (g/l) glucose 150, yeast extract 5, KH2PO4 1, MgSO4.7H2O 2, and medium pH 3 with a coefficient (R2) of 98.45%. Extracted KA was characterized using FTIR, XRD, and a scanning electron microscope. Crystalized KA was an effective antibacterial agent against six human pathogenic bacteria (Bacillus cereus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Serratia marcescens, and Serratia plymuthica). KA achieves high inhibition activity against Bacillus cereus, K. pneumonia, and S. plymuthica at 100 µg/ml concentration by 2.75, 2.85, and 2.85 compared with chloramphenicol which gives inhibition zones 1, 1.1, and 1.6, respectively. Crystalized KA had anticancer activity versus three types of cancer cell lines (Mcf-7, HepG2, and Huh7) and demonstrated high cytotoxic capabilities on HepG-2 cells that propose strong antitumor potent of KA versus hepatocellular carcinoma. The antibacterial and anticancer modes of action were illustrated using the molecular docking technique. Crystalized kojic acid from a biological source represented a promising microbial metabolite that could be utilized as an alternative antibacterial and anticancer agent effectively.


Subject(s)
Anti-Bacterial Agents , Antineoplastic Agents , Aspergillus flavus , Molecular Docking Simulation , Pyrones , Aspergillus flavus/drug effects , Aspergillus flavus/metabolism , Aspergillus flavus/genetics , Pyrones/pharmacology , Pyrones/chemistry , Pyrones/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Microbial Sensitivity Tests , Cell Line, Tumor , Bacteria/drug effects , Bacteria/genetics , Bacteria/metabolism , Bacteria/classification
9.
Polymers (Basel) ; 16(6)2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38543334

ABSTRACT

Recent progress in additive manufacturing, also known as 3D printing, has offered several benefits, including high geometrical freedom and the ability to create bioinspired structures with intricate details. Mantis shrimp can scrape the shells of prey molluscs with its hammer-shaped stick, while beetles have highly adapted forewings that are lightweight, tough, and strong. This paper introduces a design approach for bioinspired lattice structures by mimicking the internal microstructures of a beetle's forewing, a mantis shrimp's shell, and a mantis shrimp's dactyl club, with improved mechanical properties. Finite element analysis (FEA) and experimental characterisation of 3D printed polylactic acid (PLA) samples with bioinspired structures were performed to determine their compression and impact properties. The results showed that designing a bioinspired lattice with unit cells parallel to the load direction improved quasi-static compressive performance, among other lattice structures. The gyroid honeycomb lattice design of the insect forewings and mantis shrimp dactyl clubs outperformed the gyroid honeycomb design of the mantis shrimp shell, with improvements in ultimate mechanical strength, Young's modulus, and drop weight impact. On the other hand, hybrid designs created by merging two different designs reduced bending deformation to control collapse during drop weight impact. This work holds promise for the development of bioinspired lattices employing designs with improved properties, which can have potential implications for lightweight high-performance applications.

10.
Saudi J Biol Sci ; 31(2): 103921, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38268782

ABSTRACT

Carbendazim (CBZ) is a widely used fungicide that is used to control the unwanted growth of fungi on fruits and vegetables. Sixty male rats were divided into six groups, each having ten. Group one served as control, animals belonging to group two were exposed to CBZ in the measure of 200 mg/kg body weight (BW). In the third and fourth groups, rats were administered 800 mg/kg BW of Moringa oleifera (moringa oil) and Linum usitatissimum L. (flaxseed oil), plus CBZ with the same dose given to group two. Groups five and six were administered with moringa and flaxseed oils respectively for six weeks. A marked decline was seen in oxidative stress markers, reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and a rise in malondialdehyde (MDA) level in group two with severe histological disruptions. Moringa oil and flaxseed oil were used to alleviate these changes. In addition, a biocomputational molecular docking analysis of three proteins found in male rats was performed. In relation to CBZ (CID:10584007) the screened proteins namely testis-expressed protein (TX101_RAT), EPPI_RAT, and glutathione peroxidase 5 (GPX5_RAT) were docked, and their docking score were obtained (-5.9 kcal/mol), (-5.8 kcal/mol) and (-5.6 kcal/mol) respectively. By examining these interactions in 2D and 3D structures, a detailed understanding of the unique and specific binding affinity, hydrogen bonds, hydrophobic interactions, ionic bonds, and water bonds were obtained. Structure-based virtual screening (SBVS) molecular docking analysis showed that protein interaction with CBZ causes reproductive complications in protein expression and functions by hampering their normal function and blocking active sites.

11.
Plants (Basel) ; 13(2)2024 Jan 05.
Article in English | MEDLINE | ID: mdl-38256707

ABSTRACT

Breast cancer (BC) is the largest contributor to cancer deaths in women worldwide. Various parts of plants, including fruits, are known for their therapeutic properties and are used in traditional medicine. Fruit species exhibit anticancer activities due to the presence of bioactive natural compounds such as flavonoids and carotenoids. The Vaccinium spp. are fleshy berry-like drupes and are rich in bioactive compounds, with flavonols, flavanols, chalcones, and phenolic acids as the major groups of compounds. While there is clear evidence linking Vaccinium berries with a decreased risk of BC both in in vivo and in vitro experiments, the exact mechanisms involved in the protective effects of Vaccinium spp. rich extracts on BC cells are not fully understood. Thus, the purpose of this review is to highlight the mechanisms of action involved in the therapeutic potential of Vaccinium berries against BC in experimental models.

12.
Life (Basel) ; 13(12)2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38137841

ABSTRACT

Fetal growth restriction (FGR) is a pathological state that represents a fetus's inability to achieve adequate growth during pregnancy. Several maternal, placental, and fetal factors are likely associated with FGR etiology. FGR is linked to severe fetal and neonatal complications, as well as adverse health consequences in adulthood. Numerous randomized controlled trials (RCTs) have demonstrated improved growth in FGR fetuses with promising treatment strategies such as maternal micronutrient, amino acid, and nitric oxide supplementation. Elevated inflammation in pregnant women diagnosed with FGR has been associated with an imbalance between pro- and anti-inflammatory cytokines. Gut microbiota dysbiosis may result in increased FGR-related inflammation. Probiotic treatment may relieve FGR-induced inflammation and improve fetal growth. The aim of this review is to provide an overview of the gut microbiota and inflammatory profiles associated with FGR and explore the potential of probiotics in treating FGR.

13.
Int J Mol Sci ; 24(20)2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37894889

ABSTRACT

Flavonoids are the largest group of polyphenols, represented by many compounds that exhibit high anticancer properties. Quercetin (Q) and its main derivatives (rutin, quercitrin, isoquercitrin, isorhamnetin, tamarixetin, rhamnetin, and hyperoside) in the class of flavonols have been documented to exert anticancer activity. Q has been shown to be useful in the treatment of non-small cell lung cancer (NSCLC), as demonstrated by in vitro/in vivo studies, due to its antitumor, anti-inflammatory, anti-proliferative, anti-angiogenesis, and apoptotic properties. Some flavonoids (flavone, anthocyanins, and proanthocyanidins) have been demonstrated to be effective in nicotine-induced NSCLC treatment. However, the molecular mechanisms of quercetin derivatives (QDs) in nicotine-induced NSCLC treatment remain unclear. Thus, this review aims to summarize the available literature on the therapeutic effects of QDs in nicotine-induced NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Quercetin/pharmacology , Quercetin/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Nicotine/pharmacology , Nicotine/therapeutic use , Anthocyanins/therapeutic use , Lung Neoplasms/drug therapy , Flavonoids/pharmacology
14.
Cureus ; 15(8): e42807, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37664377

ABSTRACT

Background Foot problems continue to be the leading cause of hospital admissions among people with diabetes. The objective of this study was to explore and assess the knowledge and attitudes of individuals about diabetic foot ulcers in the Asser region, Saudi Arabia. Methodology An anonymous, online, cross-sectional survey was conducted. The questionnaire was distributed through commonly used social media platforms such as Instagram, Facebook, and Twitter. Results A total of 445 participants were included in this survey. Overall, 37.1% (165) were aged 18-25 years, 64.3% (286) were women, and 75.7% (337) had university-level education. A significant number of participants had relatives with diabetes (57.1%, 254), while a smaller percentage reported having diabetes themselves (7.3%, 33), and a substantial proportion were neither diabetic nor had a relative with diabetes (35.6%, (158). Nearly two-fifths of the participants (37.8%, 168) received information about diabetes and diabetic foot care from physicians, and 34.1% (152) of the participants accessed information online. There were significant differences between those who did not have diabetes mellitus (DM) and those who had DM or whose relatives were diabetic in responses to the following questions: "Do you think that diabetes may cause gangrene in the foot?" (50.9% (205) vs. 45.7% (32), p = 0.019), "Do you think that preventing diabetic foot ulcers is more important than treating diabetic foot ulcers?" (60.8% (228) vs. 46.9% (60), p = 0.002), and "Do you think it is important to constantly monitor diabetic foot wounds?" (63.1% (200) vs. 30.4% (17), p < 0.001). There was a statistically significant difference between groups in the practice of daily foot checks, washing feet, moisturizing feet, keeping feet away from hot and cold, and nail care (p < 0.001). Conclusions The participants in the study showed a lack of knowledge regarding diabetic foot care, indicating the potential for better outcomes through the implementation of enhanced health education programs.

15.
Micromachines (Basel) ; 14(8)2023 Aug 20.
Article in English | MEDLINE | ID: mdl-37630178

ABSTRACT

The Ti6Al4V alloy has many advantages, such as being lightweight, formal, and resistant to corrosion. This makes it highly desirable for various applications, especially in the aerospace industry. Laser Powder Bed Fusion (LPBF) is a technique that allows for the production of detailed and unique parts with great flexibility in design. However, there are challenges when it comes to achieving high-quality surfaces and porosity formation in the material, which limits the wider use of LPBF. To tackle these challenges, this study uses statistical techniques called Design of Experiments (DoE) and Analysis of Variance (ANOVA) to investigate and optimise the process parameters of LPBF for making Ti6Al4V components with improved density and surface finish. The parameters examined in this study are laser power, laser scan speed, and hatch space. The optimisation study results show that using specific laser settings, like a laser power of 175 W, a laser scan speed of 1914 mm/s, and a hatch space of 53 µm, produces Ti6Al4V parts with a high relative density of 99.54% and low top and side surface roughness of 2.6 µm and 4.3 µm, respectively. This promising outcome demonstrates the practicality of optimising Ti6Al4V and other metal materials for a wide range of applications, thereby overcoming existing limitations and further expanding the potential of LPBF while minimising inherent process issues.

16.
Front Microbiol ; 14: 1219823, 2023.
Article in English | MEDLINE | ID: mdl-37547698

ABSTRACT

Sugar beet is one of the greatest sources for producing sugar worldwide. However, a group of bacteria grows on beets during the storage process, leading to a reduction in sucrose yield. Our study focused on identifying common bacterial species that grow on beets during manufacturing and contribute to sucrose loss. The ultimate goal was to find a potential antibacterial agent from various plant extracts and oils to inhibit the growth of these harmful bacteria and reduce sucrose losses. The screening of bacterial species that grow on beet revealed that a large group of mesophilic bacteria, such as Bacillus subtilis, Leuconostoc mesenteroides, Pseudomonas fluorescens, Escherichia coli, Acinetobacter baumannii, Staphylococcus xylosus, Enterobacter amnigenus, and Aeromonas species, in addition to a dominant thermophilic species called Bacillus thermophilus, were found to be present during the manufacturing of beets. The application of 20 plant extracts and 13 different oils indicated that the extracts of Geranium gruinum, Datura stramonium, and Mentha spicata were the best antibacterials to reduce the growth of B. thermophilus with inhibition zones equal to 40, 39, and 35 mm, respectively. In contrast, the best active oils for inhibiting the growth of B. thermophilus were Mentha spicata and Ocimum bacilicum, with an inhibitory effect of 50 and 45 mm, respectively. RAPD-PCR with different primers indicated that treating sugar juice with the most effective oils against bacteria resulted in new recombinant microorganisms, confirming their roles as strong antibacterial products. The characterization of Mentha spicata and Ocimum bacilicum oils using GC/MS analysis identified cis-iso pulegone and hexadecanoic acid as the two main bioactive compounds with potential antibacterial activity. An analysis of five genes using DD-PCR that have been affected due to antibacterial activity from the highly effective oil from Mentha spicata concluded that all belonged to the family of protein defense. Our findings indicate that the application of these pure antibacterial plant extracts and oils would minimize the reduction of sucrose during sugar production.

17.
Materials (Basel) ; 16(14)2023 Jul 09.
Article in English | MEDLINE | ID: mdl-37512179

ABSTRACT

The current work investigates the possibility of fabricating additive manufacturing products in solid-state form, from AA2011-T6 of 40 mm diameter rods as a feedstock, using an additive friction stir deposition (A-FSD) technique. The use of large diameter feedstocks, especially high-strength aluminum alloys (2XXX series), is a challenge, as it necessitates high power and the critical selection of the optimal A-FSD parameters, such as feed rate and spindle rotation speed. The study included applying a wide range of spindle rotation speeds, ranging from 400 to 1200 rpm, at three levels of feeding rates of 1, 3, and 5 mm/min. The AA2011-T6 friction stir deposited parts (FSDPs) were visually evaluated. This was followed by an examination of macrostructures through the thickness of the fabricated specimens. The characterization of microstructures was also carried out using optical microscopy and a scanning electron microscope equipped with advanced EDS analysis. Furthermore, the mechanical properties in terms of hardness and compressive strength of the AA2011-T6 base material (BM) and deposited materials were evaluated. Sound, additively manufactured products were successfully fabricated from 40 mm diameter AA2011-T6 feedstocks using the suggested deposition variables of 600 and 800 rpm spindle speeds and feeding rates of 1, 3, and 5 mm/min. The results indicated that the spindle speed and feeding rate govern the quality of the FSDPs. Furthermore, the axial load during the A-FSD process increased with increasing these parameters. In comparison to the AA2011-T6 BM, the additively deposited materials showed a refined grain structure and uniform dispersion of the fragment precipitates in their continuous multi-layers. The reduction ratio in grain size attains 71.56%, 76%, and 81.31% for the FSDPs processed at 800 rpm spindle speed and feeding rates of 1, 3 and 5 mm/min, respectively, compared to the grain size of BM. The Al2Cu and Al7Cu2Fe intermetallics are detected in the AA2011-T6 BM, and their deposited parts are in different shapes of spherical, almost spherical, irregular, and rod-like shapes. The compressive strength and hardness of the deposited parts increased with increasing spindle speed and feeding speeds. At a spindle speed of 800 rpm and a 5 mm/min feeding rate, the higher hardness and compressive strength gained were 85% and 93%, respectively, from that of the AA2011-T6 feedstock.

18.
Materials (Basel) ; 16(14)2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37512398

ABSTRACT

Selecting an economically suitable welding technique and optimizing welding parameters to obtain high joint quality is considered a challenge for expanding the 5xxx aluminum alloy series in various industrial applications. This work aims to investigate the effect of applying different welding techniques, tungsten inert gas (TIG) and metal inert gas (MIG), as fusion welding processes compared to friction stir welding (FSW), a solid-state joining process, on the joint performance of the produced 5 mm thick similar AA5083-H111 butt weldments at different welding conditions. Different methods were used to evaluate the quality of the produced joints, including visual inspection, radiographic testing (RT), and macrostructure evaluation, in addition to hardness and tensile tests. The fracture surface of the tensile-failed specimens was also investigated using a scanning electron microscope (SEM). Furthermore, the current study ended with an economic analysis of the welding techniques used. The results showed that, for the friction stir-welded joints, the radiographic films revealed defect-free joints at the two applied travel speeds of 100 mm/min and 400 mm/min and a constant tool rotating speed of 400 rpm. In addition, only one joint was welded by MIG at a welding current of 130 Amp, with a 19 L/min flow rate of pure argon. In contrast, the radiographic films showed internal defects such as lack of fusion (LOF), lack of penetration (LOP), and porosity (P) for the two joints welded by TIG and one joint welded by MIG. The hardness of the welded joints was enhanced over the AA5083-H111 base material (BM) by 24-29, 31-35, and 46-50% for the MIG, TIG, and FSW joints, respectively. The maximum ultimate tensile strength was obtained for the FSW joint welded at a 400 mm/min travel speed. Adopting FSW in shipbuilding applications can further produce the AA5083-H11 joints with higher quality and efficiency than fusion welding techniques such as MIG and TIG processes. In addition, time and cost comparisons between TIG, MIG, and FSW were performed for five-millimeter-thick and one-meter-long AA5083-H111.

19.
Materials (Basel) ; 16(14)2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37512410

ABSTRACT

As a main goal of this work, a novel generation of cellular materials has been developed and manufactured by the kelvin cell model to be offered for different multifunctional applications. These Open-Cell Aluminum Foams (OCAF) have 85% porosities of spherical-shaped pores with a diameter of 11 mm. Several foamed square-section specimens were used. This work investigated the impact of different new quasi-static biaxial loading complexities on the mechanical behavior of such foams. Thus, new S-profiled rigs were already designed for examining the behavior of tested foams under biaxial loading conditions with different reverse torsional components named ACTP-S. After testing, their high specific strength and high energy absorption abilities have been characterized. Thus, in addition to the reference uniaxial test, all other tests were conducted at a speed of 5 mm/min. Thus, the mechanical responses of this foam are affected by loading complexities which are simple uniaxial, intermediate-biaxial (Bi-45°), and sever-biaxial (Bi-60°). These results were compared to the classical Absorption using Compression-Torsion Plastique (ACTP) responses. It was concluded that the highest dissipated energy increases with the increase in loading path complexity. Note that the energy absorption of the foam is essentially governed by its collapse mode.

20.
Polymers (Basel) ; 15(13)2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37447435

ABSTRACT

Carbon-fibre-reinforced plastic (CFRP) is increasingly being used in various applications including aerospace, automotive, wind energy, sports, and robotics, which makes the precision modelling of its machining operations a critical research area. However, the classic finite element modelling (FEM) approach has limitations in capturing the complexity of machining, particularly with regard to the interaction between the fibre-matrix interface and the cutting edge. To overcome this limitation, a hybrid approach that integrates smoothed particle hydrodynamics (SPHs) with FEM was developed and tested in this study. The hybrid FEM-SPH approach was compared with the classic FEM approach and validated with experimental measurements that took into account the cutting tool's round edge. The results showed that the hybrid FEM-SPH approach outperformed the classic FEM approach in predicting the thrust force and bounce back of CFRP machining due to the integrated cohesive model and the element conversion after failure in the developed approach. The accurate representation of the fibre-matrix interface in the FEM-SPH approach resulted in predicting precise chip formation in terms of direction and morphology. Nonetheless, the computing time of the FEM-SPH approach is higher than the classic FEM. The developed hybrid FEM-SPH model is promising for improving the accuracy of simulation in machining processes, combining the benefits of both techniques.

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