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Displaying publications 21 - 26 of 26 in total

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Ultrasonically extracted β-d-glucan from artificially cultivated mushroom, characteristic properties and antioxidant activity

Alzorqi I, Sudheer S, Lu TJ, Manickam S

Ultrason Sonochem, 2017 Mar;35(Pt B):531-540.
PMID: 27161557 DOI: 10.1016/j.ultsonch.2016.04.017

Ganoderma mushroom cultivated recently in Malaysia to produce chemically different nutritional fibers has attracted the attention of the local market. The extraction methods, molecular weight and degree of branching of (1-3; 1-6)-β-d-glucan polysaccharides is of prime importance to determine its antioxidant bioactivity. Therefore three extraction methods i.e. hot water extraction (HWE), soxhlet extraction (SE) and ultrasound assisted extraction (US) were employed to study the total content of (1-3; 1-6)-β-d-glucans, degree of branching, structural characteristics, monosaccharides composition, as well as the total yield of polysaccharides that could be obtained from the artificially cultivated Ganoderma. The physical characteristics by HPAEC-PAD, HPGPC and FTIR, as well as the antioxidant in vitro assays of DPPH scavenging activity and ferric reducing power (FRAP) indicated that (1-3; 1-6)-β-d-glucans of Malaysian mushroom have better antioxidant activity, higher molecular weight and optimal degree of branching when extracted by US in comparison with conventional methods.

Matched MeSH terms: Ultrasonic Waves*
Fulltext Effect of heat and thermosonication on kinetics of peroxidase inactivation and vitamin C degradation in seedless guava (Psidium guajava L.)

Ali, G., Russly, A.R., Jamilah, B., Azizah, O., Mandana, B.

International Food Research Journal, 2011;18(4):1289-1294.
MyJurnal

This study aims to evaluate the effect of heat and the simultaneous application of heat (80-95°C) and ultrasonic waves (thermosonication) on the inactivation kinetic of peroxidase and vitamin C degradation in seedless guava. Ultrasonic wave’s amplitudes except 25 and 100% had significant (P 0.98). In the heat blanching process, the peroxidase inactivation rate constant increased from 1.1×10-2 to 4.6×10-2 s-1. However, the inactivation rate of peroxidase was increased by 1.5–3 times in the temperature range 80–95ºC, with the 50 and 75% ultrasonic wave amplitudes, respectively. Decreases in vitamin C contents due to blanching treatments were found. Blanching processes at high temperature and short time resulted in higher vitamin C retention. It was found that thermosonication treatment inactivates seedless guava peroxidase at less severe blanching conditions and consequently retains vitamin C content at higher levels. The present findings will help to design the blanching conditions in order to reduce the severity of conventional thermal treatments and, therefore, improving the quality of the thermally treated product.

Matched MeSH terms: Ultrasonic Waves
Sim-to-Real: Employing ultrasonic guided wave digital surrogates and transfer learning for damage visualization

Alguri KS, Chia CC, Harley JB

Ultrasonics, 2021 Mar;111:106338.
PMID: 33338729 DOI: 10.1016/j.ultras.2020.106338

Wavefield imaging is a powerful visualization tool in nondestructive evaluation for studying ultrasonic wave propagation and its interactions with damage. To isolate and study damage scattering, damage-free baseline data is often subtracted from a wavefield. This is often necessary because the damage wavefield can be orders of magnitude weaker than the incident waves. Yet, baselines are not always accessible. When the baselines are accessible, the experimental conditions for the baseline and test data must be extremely similar. Researchers have created several baseline-free approaches for isolating damage wavefields, but these often rely on specific experimental setups. In this paper, we discuss a flexible approach based on ultrasonic guided wave digital surrogates (i.e., numerical simulations of incident waves) and transfer learning. We demonstrate this approach with two setups. We first isolate reflections from a circular, 2 mm diameter half-thickness hole on a 10 × 10 cm steel plate. We then isolate 8 circular, half-thickness holes of various diameters from 1 mm to 40 mm on a 60 × 60 cm steel plate. The second plate has a non-square geometry and the data has multi-path reflections. With both data sets, we isolate damage reflections without explicit experimental baselines. We also briefly illustrate the comparison of our dictionary learning method with wavenumber filtering technique which is often used to enhance the defect wavefields.

Matched MeSH terms: Ultrasonic Waves
Fulltext Effect of low level laser and low intensity pulsed ultrasound therapy on bone remodeling during orthodontic tooth movement in rats

Alazzawi MMJ, Husein A, Alam MK, Hassan R, Shaari R, Azlina A, et al.

Prog Orthod, 2018 Apr 16;19(1):10.
PMID: 29658096 DOI: 10.1186/s40510-018-0208-2

BACKGROUND: Quality bone regeneration, which leads to the improvement of bone remodeling, is essential for orthodontic treatment. In order to improve bone regeneration and increase the amount of tooth movement, different techniques have been implemented. The object of this study is to compare the effects of low-level laser therapy (LLLT), low-intensity pulsed ultrasound (LIPUS), and their combination on bone remodeling during orthodontic tooth movement.
METHODS: Eighty (80) male, 6-week-old Sprague Dawley rats were grouped in to four groups, the first group was irradiated with (940 nm) diode laser, second group with LIPUS, and third group with combination of both LLLT and LIPUS. A forth group used was a control group in an incomplete block split-mouth design. The LLLT and LIPUS were used to treat the area around the moving tooth once a day on days 0-7, then the experiment was ended in each experimental endpoint (1, 3, 7, 14, and 21 days). For amount of tooth movement, models were imaged and analyzed. Histological examination was performed after staining with (hematoxylin and eosin) and (alizarin red and Alcian Blue) stain. One step reverse transcription-polymerase chain reaction RT-PCR was also performed to elucidate the gene expression of RANK, RANKL, OPG, and RUNX-2.
RESULTS: The amount of tooth movement, the histological bone remodeling, and the RT-PCR were significantly greater in the treatment groups than that in the control group. Among the treatment groups, the combination group was the highest and the LIPUS group was the lowest.
CONCLUSION: These findings suggest that LLLT and LIPUS can enhance the velocity of tooth movement and improve the quality of bone remodeling during orthodontic tooth movement.

Matched MeSH terms: Ultrasonic Waves*
Fulltext Histological evaluation of the effect of laser and ultrasound on bone fracture healing

Al-Habib, May F., Al-Ani, Imad M., Salman, Mohammad O., Faleh, Farah W.

International Medical Journal Malaysia, 2017;16(11):24-24.
MyJurnal

To study the effect of both laser and ultrasound radiation on bone fracture
healing process. (Copied from article).

Matched MeSH terms: Ultrasonic Waves
Ultrasound-assisted weak-acid hydrolysis of crystalline starch nanoparticles for chemical enhanced oil recovery

Agi A, Junin R, Arsad A, Abbas A, Gbadamosi A, Azli NB, et al.

Int J Biol Macromol, 2020 Apr 01;148:1251-1271.
PMID: 31760018 DOI: 10.1016/j.ijbiomac.2019.10.099

Ascorbic acid was used for the first time to synthesize crystalline starch nanoparticles (CSNP). The physical properties of the CSNP were investigated. Rheological properties of the crystalline starch nanofluid (CSNF) were compared with native cassava starch (CS) and commercial polymer xanthan. Interfacial properties of the CSNF at the interface of oil and water (O/W) were investigated at different concentrations and temperatures. Wettability alteration efficiency of CSNF on oil-wet sandstone surface was investigated using the sessile drop method. Core flooding experiment was conducted at reservoir conditions. The methods were effective in producing spherical and polygonal nanoparticles with a mean diameter of 100 nm and increased in crystallinity of 7%. Viscosity increased with increase in surface area and temperature of the CSNF compared to a decrease in viscosity as the temperature increases for xanthan. Interfacial tension (IFT) decreased with increase in concentration of CSNF, electrolyte and temperature. The results show that CSNF can change the wettability of sandstone at low concentration, high salinity and elevated temperature. Pressure drops data shows stability of CSNF at 120 °C. The formation of oil bank was enough to increase oil recovery by 23%.

Matched MeSH terms: Ultrasonic Waves*