Displaying publications 101 - 120 of 135 in total

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  1. Cellulose acetate from oil palm empty fruit bunch via a one step heterogeneous acetylation
    Wan Daud WR, Djuned FM
    Carbohydr Polym, 2015 Nov 5;132:252-60.
    PMID: 26256348 DOI: 10.1016/j.carbpol.2015.06.011
    Acetone soluble oil palm empty fruit bunch cellulose acetate (OPEFB-CA) of DS 2.52 has been successfully synthesized in a one-step heterogeneous acetylation of OPEFB cellulose without necessitating the hydrolysis stage. This has only been made possible by the mathematical modeling of the acetylation process by manipulating the variables of reaction time and acetic anhydride/cellulose ratio (RR). The obtained model was verified by experimental data with an error of less than 2.5%. NMR analysis showed that the distribution of the acetyl moiety among the three OH groups of cellulose indicates a preference at the C6 position, followed by C3 and C2. XRD revealed that OPEFB-CA is highly amorphous with a degree of crystallinity estimated to be ca. 6.41% as determined from DSC. The OPEFB-CA films exhibited good mechanical properties being their tensile strength and Young's modulus higher than those of the commercial CA.
    Matched MeSH terms: Elastic Modulus
  2. Structure-property relationships of iron-hydroxyapatite ceramic matrix nanocomposite fabricated using mechanosynthesis method
    Nordin JA, Prajitno DH, Saidin S, Nur H, Hermawan H
    Mater Sci Eng C Mater Biol Appl, 2015 Jun;51:294-9.
    PMID: 25842138 DOI: 10.1016/j.msec.2015.03.019
    Hydroxyapatite (HAp) is an attractive bioceramics due to its similar composition to bone mineral and its ability to promote bone-implant interaction. However, its low strength has limited its application as load bearing implants. This paper presented a work focusing on the improvement of HAp mechanical property by synthesizing iron (Fe)-reinforced bovine HAp nanocomposite powders via mechanosynthesis method. The synthesis process was performed using high energy milling at varied milling time (3, 6, 9, and 12h). The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and scanning electron microscopy (SEM). Its mechanical properties were investigated by micro-Vicker's hardness and compression tests. Results showed that milling time directly influenced the characteristics of the nanocomposite powders. Amorphous BHAp was formed after 9 and 12h milling in the presence of HPO4(2-) ions. Continuous milling has improved the crystallinity of Fe without changing the HAp lattice structure. The nanocomposite powders were found in spherical shape, agglomerated and dense after longer milling time. The hardness and Young's modulus of the nanocomposites were also increased at 69% and 66%, respectively, as the milling time was prolonged from 3 to 12h. Therefore, the improvement of the mechanical properties of nanocomposite was attributed to high Fe crystallinity and homogenous, dense structure produced by mechanosynthesis.
    Matched MeSH terms: Elastic Modulus
  3. Fulltext Physicochemical Characterization of Bilayer Hybrid Nanocellulose-Collagen as a Potential Wound Dressing
    Ooi KS, Haszman S, Wong YN, Soidin E, Hesham N, Mior MAA, et al.
    Materials (Basel), 2020 Sep 30;13(19).
    PMID: 33007893 DOI: 10.3390/ma13194352
    The eminent aim for advance wound management is to provide a great impact on the quality of life. Therefore, an excellent strategy for an ideal wound dressing is being developed that eliminates certain drawbacks while promoting tissue regeneration for the prevention of bacterial invasion. The aim of this study is to develop a bilayer hybrid biomatrix of natural origin for wound dressing. The bilayer hybrid bioscaffold was fabricated by the combination of ovine tendon collagen type I and palm tree-based nanocellulose. The fabricated biomatrix was then post-cross-linked with 0.1% (w/v) genipin (GNP). The physical characteristics were evaluated based on the microstructure, pore size, porosity, and water uptake capacity followed by degradation behaviour and mechanical strength. Chemical analysis was performed using energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectrophotometry (FTIR), and X-ray diffraction (XRD). The results demonstrated a uniform interconnected porous structure with optimal pore size ranging between 90 and 140 μm, acceptable porosity (>70%), and highwater uptake capacity (>1500%). The biodegradation rate of the fabricated biomatrix was extended to 22 days. Further analysis with EDX identified the main elements of the bioscaffold, which contains carbon (C) 50.28%, nitrogen (N) 18.78%, and oxygen (O) 30.94% based on the atomic percentage. FTIR reported the functional groups of collagen type I (amide A: 3302 cm-1, amide B: 2926 cm-1, amide I: 1631 cm-1, amide II: 1547 cm-1, and amide III: 1237 cm-1) and nanocellulose (pyranose ring), thus confirming the presence of collagen and nanocellulose in the bilayer hybrid scaffold. The XRD demonstrated a smooth wavy wavelength that is consistent with the amorphous material and less crystallinity. The combination of nanocellulose with collagen demonstrated a positive effect with an increase of Young's modulus. In conclusion, the fabricated bilayer hybrid bioscaffold demonstrated optimum physicochemical and mechanical properties that are suitable for skin wound dressing.
    Matched MeSH terms: Elastic Modulus
  4. Fulltext Process Optimization of Ultra-High Molecular Weight Polyethylene/Cellulose Nanofiber Bionanocomposites in Triple Screw Kneading Extruder by Response Surface Methodology
    Sharip NS, Ariffin H, Andou Y, Shirosaki Y, Bahrin EK, Jawaid M, et al.
    Molecules, 2020 Sep 30;25(19).
    PMID: 33008017 DOI: 10.3390/molecules25194498
    Incorporation of nanocellulose could improve wear resistance of ultra-high molecular weight polyethylene (UHMWPE) for an artificial joint application. Yet, the extremely high melt viscosity of the polymer may constrict the mixing, leading to fillers agglomeration and poor mechanical properties. This study optimized the processing condition of UHMWPE/cellulose nanofiber (CNF) bionanocomposite fabrication in triple screw kneading extruder by using response surface methodology (RSM). The effect of the process parameters-temperature (150-190 °C), rotational speed (30-60 rpm), and mixing time (30-45 min)-on mechanical properties of the bionanocomposites was investigated. Homogenous filler distribution, as confirmed by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analysis, was obtained through the optimal processing condition of 150 °C, 60 rpm, and 45 min. The UHMWPE/CNF bionanocomposites exhibited improved mechanical properties in terms of Young's and flexural modulus by 11% and 19%, respectively, as compared to neat UHMWPE. An insignificant effect was observed when maleic anhydride-grafted-polyethylene (MAPE) was added as compatibilizer. The obtained results proved that homogenous compounding of high melt viscosity UHMWPE with CNF was feasible by optimizing the melt blending processing condition in triple screw kneading extruder, which resulted in improved stiffness, a contributing factor for wear resistance.
    Matched MeSH terms: Elastic Modulus
  5. Preparation and characterization of cockle shell aragonite nanocomposite porous 3D scaffolds for bone repair
    Mahmood SK, Zakaria MZAB, Razak ISBA, Yusof LM, Jaji AZ, Tijani I, et al.
    Biochem Biophys Rep, 2017 Jul;10:237-251.
    PMID: 28955752 DOI: 10.1016/j.bbrep.2017.04.008
    The demands for applicable tissue-engineered scaffolds that can be used to repair load-bearing segmental bone defects (SBDs) is vital and in increasing demand. In this study, seven different combinations of 3 dimensional (3D) novel nanocomposite porous structured scaffolds were fabricated to rebuild SBDs using an extraordinary blend of cockle shells (CaCo3) nanoparticles (CCN), gelatin, dextran and dextrin to structure an ideal bone scaffold with adequate degradation rate using the Freeze Drying Method (FDM) and labeled as 5211, 5400, 6211, 6300, 7101, 7200 and 8100. The micron sized cockle shells powder obtained (75 µm) was made into nanoparticles using mechano-chemical, top-down method of nanoparticles synthesis with the presence of the surfactant BS-12 (dodecyl dimethyl bataine). The phase purity and crystallographic structures, the chemical functionality and the thermal characterization of the scaffolds' powder were recognized using X-Ray Diffractometer (XRD), Fourier transform infrared (FTIR) spectrophotometer and Differential Scanning Calorimetry (DSC) respectively. Characterizations of the scaffolds were assessed by Scanning Electron Microscopy (SEM), Degradation Manner, Water Absorption Test, Swelling Test, Mechanical Test and Porosity Test. Top-down method produced cockle shell nanoparticles having averagely range 37.8±3-55.2±9 nm in size, which were determined using Transmission Electron Microscope (TEM). A mainly aragonite form of calcium carbonate was identified in both XRD and FTIR for all scaffolds, while the melting (Tm) and transition (Tg) temperatures were identified using DSC with the range of Tm 62.4-75.5 °C and of Tg 230.6-232.5 °C. The newly prepared scaffolds were with the following characteristics: (i) good biocompatibility and biodegradability, (ii) appropriate surface chemistry and (iii) highly porous, with interconnected pore network. Engineering analyses showed that scaffold 5211 possessed 3D interconnected homogenous porous structure with a porosity of about 49%, pore sizes ranging from 8.97 to 337 µm, mechanical strength 20.3 MPa, Young's Modulus 271±63 MPa and enzymatic degradation rate 22.7 within 14 days.
    Matched MeSH terms: Elastic Modulus
  6. Shear wave elastography accurately detects chronic changes in renal histopathology
    Leong SS, Wong JHD, Md Shah MN, Vijayananthan A, Jalalonmuhali M, Chow TK, et al.
    Nephrology (Carlton), 2021 Jan;26(1):38-45.
    PMID: 33058334 DOI: 10.1111/nep.13805
    AIM: Renal biopsy is the gold standard for the histological characterization of chronic kidney disease (CKD), of which renal fibrosis is a dominant component, affecting its stiffness. The aim of this study was to investigate the correlation between kidney stiffness obtained by shear wave elastography (SWE) and renal histological fibrosis.

    METHODS: Shear wave elastography assessments were performed in 75 CKD patients who underwent renal biopsy. The SWE-derived estimates of the tissue Young's modulus (YM), given as kilopascals (kPa), were measured. YM was correlated to patients' renal histological scores, broadly categorized into glomerular, tubulointerstitial and vascular scores.

    RESULTS: Young's modulus correlates significantly with tubulointerstitial score (ρ = 0.442, P 

    Matched MeSH terms: Elastic Modulus
  7. Fulltext Electrical resistivity, thermal stability and tensile strength of rice husk flour-plastic waste composites
    Shahril Anuar Bahari, Kamrie Kamlon, Masitah Abu Kassim
    Scientific Research Journal, 2012;9(2):0-0.
    MyJurnal
    In this study, the rice husk flour-plastic waste composites (RPC) was produced from polypropylene (PP) and high density polyethylene (HDPE) wastes with 30 and 50% rice husk flour (RHF) contents. RPC was made by melt compounding and compression moulding processes. The electrical resistivity, thermal stability and tensile strength of RPC were determined. The RPC was tested in electrical resistivity and tensile strength according to the ASTM D-257 and ASTM D-638 respectively, while thermal stability was tested using thermogravimetric analysis (TGA) method. From the results, high content of RHF reduces all properties, except for tensile modulus of elasticity (TMOE) in tensile strength test. The ability of moisture absorption and the presence of hemicelluloses, cellulose and silica in RHF reduce the electrical resistivity and thermal stability behaviour of RPC from 50% RHF. The good binding elements and filler agglomeration in RPC from 50% RHF improve only TMOE. Insufficient stress transfer and rigid interphase occurred between RHF and plastics during tensile maximum load and elongation at break (Eb) in tensile strength test. In general, RPC from HDPE indicates better thermal stability, tensile modulus of rupture and Eb (in tensile strength test) compared to PP, based on the good behaviour of thermal conductivity, low water absorption, high molecular weight and good elongation properties of HDPE. However, RPC from PP shows good electrical resistance due to the low thermal expansion coefficient of PP.
    Matched MeSH terms: Elastic Modulus
  8. Extraction and characterization of gelatin from the feet of Pekin duck (Anas platyrhynchos domestica) as affected by acid, alkaline, and enzyme pretreatment
    Abedinia A, Ariffin F, Huda N, Nafchi AM
    Int J Biol Macromol, 2017 May;98:586-594.
    PMID: 28174080 DOI: 10.1016/j.ijbiomac.2017.01.139
    The effects of different pretreatments on yield and composition of extraction, physicochemical, and rheological properties of duck feet gelatin (DFG) were investigated. Gelatins were extracted from the whole feet of Pekin duck with an average yield of 4.09%, 3.65%, and 5.75% for acidic (Ac-DFG), alkaline (Al-DFG), and enzymatic (En-DFG) pretreatment on a wet weight basis, respectively. Proteins at 81.38%, 79.41%, 82.55%, and 87.38% were the major composition for Ac-DFG, Al-DFG, En-DFG, and bovine, respectively. Amino acid analysis showed glycine as the predominant amino acid in Ac-DFG, followed by hydroxyproline, proline, and alanine for Ac-DFG, Al-DFG, and En-DFG, respectively. Rheological analysis indicated that the maximum elastic modulus (9972.25Pa) and loss modulus (4956.28Pa) for Ac-DFG gelatin were significantly higher than those of other gelatins. Extracted gelatins contained α1 and α2 chains as the predominant components, and enzymatic gelatin had low molecular weight peptides. Fourier transform infrared spectroscopy showed that the peak of the gelatins was mainly positioned in the amide band region (amides I, II, and III). A considerable loss of molecular-order triple helical structure was also observed after pepsin treatment. In summary, duck feet gelatin has potential to replace as mammalian gelatin in food and pharmaceutical industry.
    Matched MeSH terms: Elastic Modulus
  9. Fulltext Engineering characterisation of epoxidized natural rubber-modified hot-mix asphalt
    Al-Mansob RA, Ismail A, Yusoff NI, Rahmat RA, Borhan MN, Albrka SI, et al.
    PLoS One, 2017;12(2):e0171648.
    PMID: 28182724 DOI: 10.1371/journal.pone.0171648
    Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR-asphalt mixes prepared using the wet process. Mechanical testing on the ENR-asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR-asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR-asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress.
    Matched MeSH terms: Elastic Modulus
  10. Titanium dioxide nanotubes incorporated gellan gum bio-nanocomposite film for wound healing: Effect of TiO2 nanotubes concentration
    Razali MH, Ismail NA, Mat Amin KA
    Int J Biol Macromol, 2020 Jun 15;153:1117-1135.
    PMID: 31751725 DOI: 10.1016/j.ijbiomac.2019.10.242
    The synthesized titanium dioxide nanotubes (TiO2-NTs) were emerged as wound healing enhancer as well as exhibited significant wound healing activity on Sprague Dawley rats. In our present study, the blends of GG and TiO2-NTs bio-nanocomposite film was characterised by fourier transform infrared (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis, atomic force microscopy (AFM). The morphology of TiO2-NTs was investigated using transmission electron microscopy (TEM). The mechanical properties study shows that the GG + TiO2-NTs (20 w/w %) bio-nanocomposite film possessed the highest tensile strength and young modulus which are (4.56 ± 0.15) MPa and (68 ± 1.63) MPa, respectively. GG + TiO2-NTs (20 w/w %) also displays the highest antibacterial activity with (16 ± 0.06) mm, (16 ± 0.06) mm, (14 ± 0.06) mm, and (12 ± 0.25) mm inhibition zone were recorded against Staphylococcus aureus, Streptococcus, Escherichia coli, and Pseudomonas aeruginosa. The prepared bio-nanocomposite films have good biocompatibility against 3T3 mouse fibroblast cells and caused accelerated healing of open excision type wounds on Sprague Dawley rat model. The synergistic effects of bio-nanocomposite film like good swelling and WVTR properties, excellent hydrophilic nature, biocompatibility, wound appearance and wound closure rate through in vivo test makes it a suitable candidate for wound healing applications.
    Matched MeSH terms: Elastic Modulus
  11. Fulltext The Role of Two-Step Blending in the Properties of Starch/Chitin/Polylactic Acid Biodegradable Composites for Biomedical Applications
    Olaiya NG, Nuryawan A, Oke PK, Khalil HPSA, Rizal S, Mogaji PB, et al.
    Polymers (Basel), 2020 Mar 05;12(3).
    PMID: 32151004 DOI: 10.3390/polym12030592
    The current research trend for excellent miscibility in polymer mixing is the use of plasticizers. The use of most plasticizers usually has some negative effects on the mechanical properties of the resulting composite and can sometimes make it toxic, which makes such polymers unsuitable for biomedical applications. This research focuses on the improvement of the miscibility of polymer composites using two-step mixing with a rheomixer and a mix extruder. Polylactic acid (PLA), chitin, and starch were produced after two-step mixing, using a compression molding method with decreasing composition variation (between 8% to 2%) of chitin and increasing starch content. A dynamic mechanical analysis (DMA) was used to study the mechanical behavior of the composite at various temperatures. The tensile strength, yield, elastic modulus, impact, morphology, and compatibility properties were also studied. The DMA results showed a glass transition temperature range of 50 °C to 100 °C for all samples, with a distinct peak value for the loss modulus and factor. The single distinct peak value meant the polymer blend was compatible. The storage and loss modulus increased with an increase in blending, while the loss factor decreased, indicating excellent compatibility and miscibility of the composite components. The mechanical properties of the samples improved compared to neat PLA. Small voids and immiscibility were noticed in the scanning electron microscopy images, and this was corroborated by X-ray diffraction graphs that showed an improvement in the crystalline nature of PLA with starch. Bioabsorption and toxicity tests showed compatibility with the rat system, which is similar to the human system.
    Matched MeSH terms: Elastic Modulus
  12. Fulltext Penetration mechanics of elongated female and male genitalia of earwigs
    Matsumura Y, Kamimura Y, Lee CY, Gorb SN, Rajabi H
    Sci Rep, 2021 04 12;11(1):7920.
    PMID: 33846369 DOI: 10.1038/s41598-021-86864-1
    We unveiled the penile penetration mechanics of two earwig species, Echinosoma horridum, whose intromittent organ, termed virga, is extraordinarily long, and E. denticulatum, whose virga is conversely short. We characterised configuration, geometry, material and bending stiffness for both virga and spermatheca. The short virga of E. denticulatum has a material gradient with the stiffer base, whereas the long virga of E. horridum and the spermathecae of both species are homogeneously sclerotised. The long virga of E. horridum has a lower bending stiffness than the spermatheca. The virga of E. denticulatum is overall less flexible than the spermatheca. We compared our results to a previous study on the penetration mechanics of elongated beetle genitalia. Based on the comparison, we hypothesised that the lower stiffness of the male intromittent organ comparing to the corresponding female structure is a universal prerequisite for the penetration mechanics of the elongated intromittent organ in insects.
    Matched MeSH terms: Elastic Modulus
  13. Cryopreservation versus fresh frozen meniscal allograft: A biomechanical comparative analysis
    Ahmad S, Singh VA, Hussein SI
    J Orthop Surg (Hong Kong), 2017 8 29;25(3):2309499017727946.
    PMID: 28844199 DOI: 10.1177/2309499017727946
    Meniscal allograft transplantation may be a better alternative for the treatment of irreparable meniscal injury compared to other forms of treatment. However, it remains to be seen whether the use fresh frozen allograft is better than cryopreserved allograft in treating this type of injury. We hypothesized that cryopreserved meniscal allograft would work better in maintaining the original biomechanical properties compared to fresh frozen ones, due to the lower amount of damage it incurs during the storage process. We examined young and healthy human menisci obtained from orthopedic oncology patients who underwent resection surgeries around the knee. The menisci obtained were preserved via cryopreservation and deep-freezing process. Traction tests were carried out on the menisci after 6 weeks of preservation. Twelve pairs ( N = 24) of menisci were divided equally into two groups, cryopreservation and deep frozen. There were six males and six female menisci donors for this study. The age range was between 15 and 35 years old (24.9 ± 8.6 years). Cryopreserved specimens had a higher ultimate tensile strength (UTS; 8.2 ± 1.3 Mpa vs. 13.3 ± 1.7 Mpa: p < 0.05) and elastic modulus (61.7 ± 27.6 Mpa vs. 87.0 ± 44.10 Mpa: p < 0.05) compared to the fresh frozen specimens. There was a significant difference in UTS ( p < 0.05) between the two groups but no significant difference in their elastic modulus ( p > 0.05). The elastic modulus of the preserved meniscus was similar to fresh normal menisci taken from other studies (60-120 Mpa; cryopreserved (87.0 ± 44.1) and fresh frozen (61.7 ± 27.5)). Cryopreserved menisci had a higher elastic modulus and point of rupture (UTS) compared to fresh frozen menisci. Cryopreservation proved to be a significantly better method of preservation, among the two methods of preservation in this study.
    Matched MeSH terms: Elastic Modulus
  14. AFM analysis of collagen fibrils in expanded scalp tissue after anisotropic tissue expansion
    Aziz J, Ahmad MF, Rahman MT, Yahya NA, Czernuszka J, Radzi Z
    Int J Biol Macromol, 2018 Feb;107(Pt A):1030-1038.
    PMID: 28939521 DOI: 10.1016/j.ijbiomac.2017.09.066
    Successful use of tissue expanders depends on the quality of expanded tissue. This study evaluates the impact of anisotropic self-inflating tissue expander (SITE) on the biomechanics of skin. Two different SITE were implanted subcutaneously on sheep scalps; SITE that requires 30days for maximum expansion (Group A; n=5), and SITE that requires 21days for maximum expansion (Group B; n=5). Control animals (n=5) were maintained without SITE implantation. Young's Modulus, D-periodicity, overlap and gap region length, diameter, and height difference between overlap and gap regions on collagen fibrils were analyzed using atomic force microscopy. Histology showed no significant differences in dermal thickness between control and expanded skin of groups A and B. Furthermore, most parameters of expanded skin were similar to controls (p>0.05). However, the height difference between overlap and gap regions was significantly smaller in group B compared to both control and group A (p<0.01). Strong correlation was observed between Young's Modulus of overlap and gap regions of the control and group A, but not group B. Results suggest that a relatively slower SITE can be useful in reconstructive surgery to maintain the biomechanical properties of expanded skin.
    Matched MeSH terms: Elastic Modulus
  15. Fulltext Vitamin E improved bone strength and bone minerals in male rats given alcohol
    Zakaria S, Mat-Husain SZ, Ying-Hwey K, Xin-Kai K, Mohd-Badawi A, Abd-Ghani NA, et al.
    Iran J Basic Med Sci, 2017 Dec;20(12):1360-1367.
    PMID: 29238472 DOI: 10.22038/IJBMS.2017.9610
    Objectives: Alcohol consumption induces oxidative stress on bone, which in turn increases the risk of osteoporosis. This study determined the effects of vitamin E on bone strength and bone mineral content in alcohol-induced osteoporotic rats.

    Materials and Methods: Three months old Sprague Dawley male rats were randomly divided into 5 groups: (I) control group; (II) alcohol (3g/kg) + normal saline; (III) alcohol (3g/kg) + olive oil; (IV) alcohol (3g/kg) + alpha-tocopherol (60mg/kg) and (V) alcohol (3g/kg) + palm vitamin E (60mg/kg). The treatment lasted for three months. Following sacrifice, the right tibia was subjected to bone biomechanical test while the lumbar (fourth and fifth lumbar) and left tibia bones were harvested for bone mineral measurement.

    Results: Alcohol caused reduction in bone biomechanical parameters (maximum force, ultimate stress, yield stress and Young's modulus) and bone minerals (bone calcium and magnesium) compared to control group (P<0.05). Palm vitamin E was able to improve bone biomechanical parameters by increasing the maximum force, ultimate stress and Young's modulus (P<0.05) while alpha-tocopherol was not able to. Both alpha-tocopherol and palm vitamin E were able to significantly increase tibia calcium and magnesium content while only alpha-tocopherol caused significant increase in lumbar calcium content (P<0.05).

    Conclusion: Both palm vitamin E and alpha-tocopherol improved bone mineral content which was reduced by alcohol. However, only palm vitamin E was able to improve bone strength in alcohol treated rats.

    Matched MeSH terms: Elastic Modulus
  16. Fulltext Biochemical and texture property changes during molting process of tiger prawn, Penaeus monodon
    Nor Faadila, M.I., Harivaindaran, K.V., Tajul, A. Yang
    International Food Research Journal, 2013;20(2):751-758.
    MyJurnal
    Texture and biochemical changes, specifically in moisture, protein content and amino acid profile were studied throughout the molt cycle of Panaeus monodon. This study was initiated to investigate changes that may occur in mass and tissue composition during different molting stages. Molting of Penaeus monodon are classified into 3 main stages; postmolt, intermolt and premolt. Result of biochemical analysis, shows that moisture varies from 78.02-80.88%, indicating a maximum value during postmolt and minimum value during premolt. Total protein content was found to be higher during intermolt (23.48%) and postmolt (22.27%) compared to premolt (23.10%). The result of SDS-PAGE electrophoresis shows a higher intensity of protein band during intermolt which corresponds to higher protein content. Thus, this electrophoresis method is useful as an alternative to determine different stages of shrimp molting. This is based on intensity of the protein band which is referring to protein content of the shrimp at its different stages. The amino acid profile showed that arginine, alanine, glutamic acid, glycine, lycine, and thronine increased during premolt whilst isoleucine and phenylalanine higher during postmolt. Aspartic acid and histidine was higher in intermolt than in premolt and postmolt. Texture analysis carried out give an elastic modulus value that is high during premolt compared to postmolt and intermolt. There are significant changes in texture and biochemical composition through elastic modules value and protein composition of Penaeus monodon during each stages of moltcycle.
    Matched MeSH terms: Elastic Modulus
  17. Fulltext The Impact of Halloysite on the Thermo-Mechanical Properties of Polymer Composites
    Gaaz TS, Sulong AB, Kadhum AAH, Al-Amiery AA, Nassir MH, Jaaz AH
    Molecules, 2017 May 20;22(5).
    PMID: 28531126 DOI: 10.3390/molecules22050838
    Nanotubular clay minerals, composed of aluminosilicate naturally structured in layers known as halloysite nanotubes (HNTs), have a significant reinforcing impact on polymer matrixes. HNTs have broad applications in biomedical applications, the medicine sector, implant alloys with corrosion protection and manipulated transportation of medicines. In polymer engineering, different research studies utilize HNTs that exhibit a beneficial enhancement in the properties of polymer-based nanocomposites. The dispersion of HNTs is improved as a result of pre-treating HNTs with acids. The HNTs' percentage additive up to 7% shows the highest improvement of tensile strength. The degradation of the polymer can be also significantly improved by doping a low percentage of HNTs. Both the mechanical and thermal properties of polymers were remarkably improved when mixed with HNTs. The effects of HNTs on the mechanical and thermal properties of polymers, such as ultimate strength, elastic modulus, impact strength and thermal stability, are emphasized in this study.
    Matched MeSH terms: Elastic Modulus
  18. Fulltext Cellulose nanocrystals/ZnO as a bifunctional reinforcing nanocomposite for poly(vinyl alcohol)/chitosan blend films: fabrication, characterization and properties
    Azizi S, Ahmad MB, Ibrahim NA, Hussein MZ, Namvar F
    Int J Mol Sci, 2014 Jun 18;15(6):11040-53.
    PMID: 24945313 DOI: 10.3390/ijms150611040
    In this study, cellulose nanocrystals/zinc oxide (CNCs/ZnO) nanocomposites were dispersed as bifunctional nano-sized fillers into poly(vinyl alcohol) (PVA) and chitosan (Cs) blend by a solvent casting method to prepare PVA/Cs/CNCs/ZnO bio-nanocomposites films. The morphology, thermal, mechanical and UV-vis absorption properties, as well antimicrobial effects of the bio-nanocomposite films were investigated. It demonstrated that CNCs/ZnO were compatible with PVA/Cs and dispersed homogeneously in the polymer blend matrix. CNCs/ZnO improved tensile strength and modulus of PVA/Cs significantly. Tensile strength and modulus of bio-nanocomposite films increased from 55.0 to 153.2 MPa and from 395 to 932 MPa, respectively with increasing nano-sized filler amount from 0 to 5.0 wt %. The thermal stability of PVA/Cs was also enhanced at 1.0 wt % CNCs/ZnO loading. UV light can be efficiently absorbed by incorporating ZnO nanoparticles into a PVA/Cs matrix, signifying that these bio-nanocomposite films show good UV-shielding effects. Moreover, the biocomposites films showed antibacterial activity toward the bacterial species Salmonella choleraesuis and Staphylococcus aureus. The improved physical properties obtained by incorporating CNCs/ZnO can be useful in variety uses.
    Matched MeSH terms: Elastic Modulus
  19. Fulltext Tocotrienol supplementation improves late-phase fracture healing compared to alpha-tocopherol in a rat model of postmenopausal osteoporosis: a biomechanical evaluation
    Mohamad S, Shuid AN, Mokhtar SA, Abdullah S, Soelaiman IN
    Evid Based Complement Alternat Med, 2012;2012:372878.
    PMID: 22829855 DOI: 10.1155/2012/372878
    This study investigated the effects of α-tocopherol and palm oil tocotrienol supplementations on bone fracture healing in postmenopausal osteoporosis rats. 32 female Sprague-Dawley rats were divided into four groups. The first group was sham operated (SO), while the others were ovariectomised. After 2 months, the right femora were fractured under anesthesia and fixed with K-wire. The SO and ovariectomised-control rats (OVXC) were given olive oil (vehicle), while both the alpha-tocopherol (ATF) and tocotrienol-enriched fraction (TEF) groups were given alpha-tocopherol and tocotrienol-enriched fraction, respectively, at the dose of 60 mg/kg via oral gavages 6 days per week for 8 weeks. The rats were then euthanized and the femora dissected out for bone biomechanical testing to assess their strength. The callous of the TEF group had significantly higher stress parameter than the SO and OVXC groups. Only the SO group showed significantly higher strain parameter compared to the other treatment groups. The load parameter of the OVXC and ATF groups was significantly lower than the SO group. There was no significant difference in the Young's modulus between the groups. In conclusion, tocotrienol is better than α-tocopherol in improving the biomechanical properties of the fracture callous in postmenopausal osteoporosis rat model.
    Matched MeSH terms: Elastic Modulus
  20. Fulltext Development and characterization of novel porous 3D alginate-cockle shell powder nanobiocomposite bone scaffold
    Bharatham BH, Abu Bakar MZ, Perimal EK, Yusof LM, Hamid M
    Biomed Res Int, 2014;2014:146723.
    PMID: 25110655 DOI: 10.1155/2014/146723
    A novel porous three-dimensional bone scaffold was developed using a natural polymer (alginate/Alg) in combination with a naturally obtained biomineral (nano cockle shell powder/nCP) through lyophilization techniques. The scaffold was developed in varying composition mixture of Alg-nCP and characterized using various evaluation techniques as well as preliminary in vitro studies on MG63 human osteoblast cells. Morphological observations using SEM revealed variations in structures with the use of different Alg-nCP composition ratios. All the developed scaffolds showed a porous structure with pore sizes ideal for facilitating new bone growth; however, not all combination mixtures showed subsequent favorable characteristics to be used for biological applications. Scaffolds produced using the combination mixture of 40% Alg and 60% nCP produced significantly promising results in terms of mechanical strength, degradation rate, and increased cell proliferation rates making it potentially the optimum composition mixture of Alg-nCP with future application prospects.
    Matched MeSH terms: Elastic Modulus
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