Displaying publications 41 - 60 of 109 in total

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  1. Daungfu O, Youpensuk S, Lumyong S
    Trop Life Sci Res, 2019 Jan;30(1):73-88.
    PMID: 30847034 DOI: 10.21315/tlsr2019.30.1.5
    Citrus canker caused by Xanthomonas citri subsp. citri is a disease affecting the yield and fruit quality of lime (Citrus aurantiifolia). This research investigated endophytic bacteria obtained from six healthy Citrus spp. to inhibit the pathogen and to control citrus canker on lime plants. Numbers of the endophytic bacteria isolated from C. aurantifolia, C. hystrix, C. maxima, C. nobilis, C. reticulata and C. sinensis were 28, 25, 29, 42, 12 and 34 isolates, respectively. The selected endophytic bacteria that were effective against X. citri subsp. citri were Bacillus amyloliquefaciens LE109, B. subtilis LE24 and B. tequilensis PO80. The optimum culture medium for an antagonistic effect on the pathogen in B. amyloliquefaciens LE109 and B. tequilensis PO80 was yeast extract peptone dextrose broth, and in B. subtilis LE24 was modified soluble starch broth. To control citrus canker in lime, young expanded leaves of lime plants were aseptically punctured and inoculated with 30 μl of bacterial suspension of the pathogen (108 CFU/ml in 0.85% NaCl) per punctured location. After the pathogenic inoculation for 24 h, the leaves were then inoculated with 30 μl of the selected endophytic bacteria (108 CFU/ml in 0.85% NaCl), and treated with 30 μl of the culture media containing bioactive compounds produced by the selected endophytic bacteria. The leaves inoculated with cell suspensions of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. However, the leaves inoculated with B. tequilensis PO80 displayed 10% disease incidence. Additionally, the leaves treated with the crude bioactive compounds of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. Notably, the leaves treated with the crude bioactive compounds of B. tequilensis PO80 displayed 5% disease incidence. The results of this study showed that the Bacillus strains play important roles in the biocontrol of citrus canker in lime.
    Matched MeSH terms: Calcium Compounds
  2. Salem A, Khandaker MM, Mahmud K, Alsufyani SJ, Majrashi AA, Rashid ZM, et al.
    Plant Physiol Biochem, 2024 Jan;206:108295.
    PMID: 38154296 DOI: 10.1016/j.plaphy.2023.108295
    The present study was conducted to investigate the effects of Trichoderma harzianum and Bacillus thuringiensis alone or with gradual levels of NPK on photosynthesis, growth, fruit quality, aroma improvement and reduced radionuclides of key lime fruits. The lemon seedlings were treated with (T0) without fertilizers as control, (T1) 100g of NPK at 100%, (T2) 5 g of Trichoderma. harzianum at 50% + 50 g of NPK at 50%, (T3) 5 g of Bacillus thuringiensis at 50% + 50 g of NPK at 50 %, (T4) 7.5 g of Trichoderma harzianum at 75% + 25 g of NPK at 25 %, (T5) 7.5 g of Bacillus thuringiensis at 75% + 25 g of NPK at 25 %, (T6) 10 g of Trichoderma harzianum at 100 % and (T7)10 g of Bacillus thuringiensis at 100 %. The results showed that T2 increased net photosynthetic rate, stomatal conductance, transpiration rate, internal CO2 concentration, fresh and dry root biomass by 209%, 74%, 56%, 376%, 69.4% and 71.6%, while, T5 increased root volume, root length, and root tip number by 27.1%, 167%, and 67%, respectively over the control trees. The microbial treatments developed cortex, vascular cylinder and tracheal elements of the root. Fruit number, length, diameter, weight, pulp thickness, pulp/peel ratio, juice, total soluble solids (TSS), pigment contents and antioxidant activity increased significantly in the T2 treatment. Vitamin C, total phenols, total flavonoids, and total sugar content increased by 1.59-, 1.66-, 1.44- and 2.07- fold in T5 treated fruits compared to the control. The two microbes increased volatile compounds and decreased radionucleotides in the fruit, moreover, 27 identified and 2 (two) unmatched volatile compounds were identified by GCMS analysis. It is concluded that T. harzianum and B. thuringiensis with 25-50 g NPK treatments improved photosynthesis, root structure, fruit growth, fruit quality, aroma and lessened radionuclides in key lime fruits.
    Matched MeSH terms: Calcium Compounds*
  3. Sharaf Aldeen EM, Jalil AA, Mim RS, Hatta AH, Hazril NIH, Chowdhury A, et al.
    Environ Res, 2023 Oct 01;234:116576.
    PMID: 37423362 DOI: 10.1016/j.envres.2023.116576
    Photocatalysis utilizing semiconductors offer a cost-effective and promising solution for the removal of pollutants. MXene and perovskites, which possess desirable properties such as a suitable bandgap, stability, and affordability, have emerged as a highly promising material for photocatalytic activity. However, the efficiency of MXene and perovskites is limited by their fast recombination rates and inadequate light harvesting abilities. Nonetheless, several additional modifications have been shown to enhance their performance, thereby warranting further exploration. This study delves into the fundamental principles of reactive species for MXene-perovskites. Various methods of modification of MXene-perovskite-based photocatalysts, including Schottky junction, Z-scheme and S-scheme are analyzed with regard to their operation, differences, identification techniques and reusability. The assemblance of heterojunctions is demonstrated to enhance photocatalytic activity while also suppressing charge carrier recombination. Furthermore, the separation of photocatalysts through magnetic-based methods is also investigated. Consequently, MXene-perovskite-based photocatalysts are seen as an exciting emerging technology that necessitates further research and development.
    Matched MeSH terms: Calcium Compounds
  4. Smran A, Abdullah M, Ahmad NA, Ben Yahia F, Fouda AM, Alturaiki SA, et al.
    PLoS One, 2024;19(3):e0299552.
    PMID: 38483853 DOI: 10.1371/journal.pone.0299552
    This research aimed to assess the stress distribution in lower premolars that were obturated with BioRoot RCS or AH Plus, with or without gutta percha (GP), and subjected to vertical and oblique forces. One 3D geometric model of a mandibular second premolar was created using SolidWorks software. Eight different scenarios representing different root canal filling techniques, single cone technique with GP and bulk technique with sealer only with occlusal load directions were simulated as follows: Model 1 (BioRoot RCS sealer and GP under vertical load [VL]), Model 2 (BioRoot RCS sealer and GP under oblique load [OL]), Model 3 (AH Plus sealer with GP under VL), Model 4 (AH Plus sealer with GP under OL), Model 5 (BioRoot RCS sealer in bulk under VL), Model 6 (BioRoot RCS in bulk under OL), Model 7 (AH Plus sealer in bulk under VL), and Model 8 (AH Plus sealer in bulk under OL). A static load of 200 N was applied at three occlusal contact points, with a 45° angle from lingual to buccal. The von Mises stresses in root dentin were higher in cases where AH Plus was used compared to BioRoot RCS. Furthermore, shifting the load to an oblique direction resulted in increased stress levels. Replacing GP with sealer material had no effect on the dentin maximum von Mises stress in BioRoot RCS cases. Presence of a core material resulted in lower stress in dentin for AH Plus cases, however, it did not affect the stress levels in dentin for cases filled with BioRoot RCS. Stress distribution in the dentin under oblique direction was higher regardless of sealer or technique used.
    Matched MeSH terms: Calcium Compounds*
  5. Eliaslankaran Z, Daud NNN, Yusoff ZM, Rostami V
    Materials (Basel), 2021 Feb 28;14(5).
    PMID: 33670914 DOI: 10.3390/ma14051140
    Coastal accretion and erosion are unavoidable processes as some coastal sediments undergo modification and stabilization. This study was conducted to investigate the geotechnical behavior of soil collected from Bagan Lalang coast and treated with lime, cement, and rice husk ash (RHA) to design a low-cost alternative mixture with environmentally friendly characteristics. Laboratory tests were carried out to analyze the physical properties of the soil (Atterberg limits and compaction properties), together with mechanical characteristics (direct shear and unconfined compressive strength (UCS) tests) to determine the effect of different ratios of stabilizer/pozzolan on the coastal soil and the optimum conditions for each mixture. Part of the purpose of this study was also to analyze the shear behavior of the coastal soil and monitor the maximum axial compressive stress that the treated specimens can bear under zero confining pressure. Compared to the natural soil, the soil treated with lime and rice husk ash (LRHA) in the ratio of 1:2 (8% lime content) showed a tremendous increase in shear stress under the normal stress of 200 kPa. The strength parameters such as the cohesion (c) and internal friction angle (ϕ) values showed a significant increase. Cohesion values increased considerably in samples cured for 90 days compared to specimens cured for 7 days with additional LRHA in the ratio of 1:2 (28%).
    Matched MeSH terms: Calcium Compounds
  6. Dahlan I, Lee KT, Kamaruddin AH, Mohamed AR
    J Hazard Mater, 2009 Jan 15;161(1):570-4.
    PMID: 18462871 DOI: 10.1016/j.jhazmat.2008.03.097
    This paper examines the effectiveness of 10 additives toward improving SO2 sorption capacities (SSC) of rice husk ash (RHA)/lime (CaO) sorbent. The additives examined are NaOH, CaCl2, LiCl, NaHCO3, NaBr, BaCl2, KOH, K2HPO4, FeCl3 and MgCl2. Most of the additives tested increased the SSC of RHA/CaO sorbent, whereby NaOH gave highest SSC (30mg SO2/g sorbent) at optimum concentration (0.25mol/l) compared to other additives examined. The SSC of RHA/CaO sorbent prepared with NaOH addition was also increases from 17.2 to 39.5mg SO2/g sorbent as the water vapor increases from 0% RH to 80% RH. This is probably due to the fact that most of additives tested act as deliquescent material, and its existence increases the amount of water collected on the surface of the sorbent, which played an important role in the reaction between the dry-type sorbent and SO2. Although most of the additives were shown to have positive effect on the SSC of the RHA/CaO sorbent, some were found to have negative or insignificant effect. Thus, this study demonstrates that proper selection of additives can improve the SSC of RHA/CaO sorbent significantly.
    Matched MeSH terms: Calcium Compounds/antagonists & inhibitors*
  7. Patsiou D, Del Rio-Cubilledo C, Catarino AI, Summers S, Mohd Fahmi A, Boyle D, et al.
    Sci Total Environ, 2020 May 01;715:136941.
    PMID: 32041050 DOI: 10.1016/j.scitotenv.2020.136941
    Lead-halide perovskite nanoparticles (NPs) are a new technology, and investigation of toxicity is of considerable importance due to the potential lead (Pb) release into the environment. The aim of the study was to investigate aqueous and dietary toxicity of Pb-halide perovskite NP and Pb in zebrafish Danio rerio. Perovskite NP toxicity was evaluated in zebrafish by mortality, gene expression, histopathology, and phylogenetic analysis of gut microbiota. Zebrafish larvae were exposed to five Pb-halide perovskite NPs in parallel with Pb(NO3)2 exposures, and zebrafish adults were exposed to the three perovskite NPs that caused the strongest effect and Pb(NO3)2. No median lethal concentration (LC50) was observed for zebrafish larvae exposed to up to 200 mg/L of perovskite NPs for 96 h. Mortality, metallothionein 2 (mt2) and δ-aminolevulinic acid dehydratase (ala-d) gene expression (24-h exposure) in zebrafish larvae after aqueous perovskite NPs exposures did not differ from total Pb concentration - response curves. The lack of differences in mortality and gene expression between perovskite NPs and soluble Pb after aqueous exposure suggest that toxicity from perovskite NPs can be attributed to bioavailable Pb rather than nano-specific effects. Induction of mt2 and reduction of ala-d expression levels in liver tissues showed Pb bioavailability after 2-d and 4-d dietary exposure to perovskite-spiked feeds. Changes in gut microbiota of adult zebrafish were detected after 14-d exposure to Pb-spiked food, but no changes were detected from perovskite-NP spiked food. The phylogenetic analysis identified different microbiome profiles of Pb-fed fish compared to perovskite-fed fish suggesting a different mechanism of toxicity. Exposure to Pb-halide perovskite NPs led to absorption of Pb likely from release of Pb ions rather than absorption of NPs. Pb-halide perovskite NPs can release bioavailable Pb and this needs to be considered during the development of this technology.
    Matched MeSH terms: Calcium Compounds
  8. Charles A, Khan MR, Ng KH, Wu TY, Lim JW, Wongsakulphasatch S, et al.
    Sci Total Environ, 2019 Apr 15;661:522-530.
    PMID: 30682605 DOI: 10.1016/j.scitotenv.2019.01.195
    In this paper, a facile synthesis method for CaFe2O4 is introduced that produces a catalyst capable of significant photocatalytic degradation of POME under visible light irradiation. The co-precipitation method was used to produce two catalysts at calcination temperatures of 550 °C and 700 °C dubbed CP550 and CP700. CP550 demonstrated the maximum COD removal of 69.0% at 0.75 g/L catalyst loading after 8 h of visible light irradiation which dropped to 61.0% after three consecutive cycles. SEM images indicated that the higher calcination temperature of CP700 led to annealing which reduced the pore volume (0.025 cm3/g) and pore diameter (10.3 nm) while simultaneously creating a smoother and more spherical surface with lower SBET (9.73 m2/g). In comparison, CP550 had a rough hair-like surface with higher SBET (27.28 m2/g) and pore volume (0.077 cm3/g) as evidenced by BET analysis. XRD data indicated the presence of CaFe5O7 in the CP550 composition which was not present in CP700. The presence of Wustite-like FeO structures in CaFe5O7 are likely the cause for lower photoluminescence intensity profile and hence better charge separation of CP550 as these structures in CaFe2O4 have been known to increase resistivity and electron localization. The COD removal of CP550 dropped from 69.0% to just 7.0% upon adding a small quantity of isopropanol into the reaction mixture indicating hydroxyl radicals as the primary reactive oxidative species.
    Matched MeSH terms: Calcium Compounds
  9. Erfani M, Saion E, Soltani N, Hashim M, Abdullah WS, Navasery M
    Int J Mol Sci, 2012;13(11):14434-45.
    PMID: 23203073 DOI: 10.3390/ijms131114434
    Calcium borate nanoparticles have been synthesized by a thermal treatment method via facile co-precipitation. Differences of annealing temperature and annealing time and their effects on crystal structure, particle size, size distribution and thermal stability of nanoparticles were investigated. The formation of calcium borate compound was characterized by X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and Thermogravimetry (TGA). The XRD patterns revealed that the co-precipitated samples annealed at 700 °C for 3 h annealing time formed an amorphous structure and the transformation into a crystalline structure only occurred after 5 h annealing time. It was found that the samples annealed at 900 °C are mostly metaborate (CaB(2)O(4)) nanoparticles and tetraborate (CaB(4)O(7)) nanoparticles only observed at 970 °C, which was confirmed by FTIR. The TEM images indicated that with increasing the annealing time and temperature, the average particle size increases. TGA analysis confirmed the thermal stability of the annealed samples at higher temperatures.
    Matched MeSH terms: Calcium Compounds/chemistry*
  10. Hatipoğlu Ö, Hatipoğlu FP, Javed MQ, Nijakowski K, Taha N, El-Saaidi C, et al.
    J Endod, 2023 Jun;49(6):675-685.
    PMID: 37094712 DOI: 10.1016/j.joen.2023.04.005
    INTRODUCTION: Direct pulp capping (DPC) procedures require the placement of a bioactive material over an exposure site without selective pulp tissue removal. This web-based multicentered survey had 3 purposes: (1) to investigate the factors that affect clinicians' decisions in DPC cases, (2) to determine which method of caries removal is preferred, and (3) to evaluate the preferred capping material for DPC.

    METHODS: The questionnaire comprised 3 sections. The first part comprised questions regarding demographic features. The second part comprised questions on how treatment plans change according to factors such as nature, location, number and size of the pulp exposure, and patients' age. The third part composed of questions on the common materials and techniques used in DPC. To estimate the effect size, the risk ratio (RR) and 95% confidence interval (CI) were calculated using a meta-analysis software.

    RESULTS: A tendency toward more invasive treatment was observed for the clinical scenario with carious-exposed pulp (RR = 2.86, 95% CI: 2.46, 2.32; P calcium silicate-based materials were preferred over calcium hydroxide-based materials (RR = 0.58, 95% CI: 0.44, 0.76; P calcium silicate-based materials appears to have replaced calcium hydroxide-based materials.

    Matched MeSH terms: Calcium Compounds/therapeutic use
  11. Tang SN, Fakhru'l-Razi A, Hassan MA, Karim MI
    PMID: 10595441
    Rubber latex effluent is a polluting source that has a high biochemical oxygen demand (BOD). It is estimated that about 100 million liters of effluent are discharged daily from rubber processing factories. Utilization of this effluent such as the use of a coupled system not only can reduce the cost of treatment but also yield a fermentation feedstock for the production of bioplastic. This study initially was carried out to increase the production of organic acids by anaerobic treatment of rubber latex effluent. It was found that through anaerobic treatment the concentration of organic acids did not increase. Consequently, separation of organic acids from rubber latex effluent by anion exchange resin was examined as a preliminary study of recovering acetic and propionic acids. However, the suspended solids (SS) content in the raw effluent was rather high which partially blocked the ion-exchange columns. Lime was used to remove the SS in the rubber latex effluent. After the lime precipitation process, organic acids were found to adsorb strongly onto the anion exchange resin. Less adsorption of organic acids onto the resin was observed before the lime precipitation. This was probably due to more sites being occupied by colloidal particles on the resin thus inhibiting the adsorption of organic acids. The initial concentration of organic acids in the raw effluent was 3.9 g/L. After ion exchange, the concentration of the organic acids increased to 27 g/L, which could be utilized for production of polyhydroxyalkanoates (PHA). For PHA accumulation stage, concentrated rubber latex effluent obtained from ion exchange resins and synthetic acetic acid were used as the carbon source. Quantitative analyses from fed batch culture via HPLC showed that the accumulation of PHA in Alcaligenes eutrophus was maximum with a concentration of 1.182 g/L when cultivated on synthetic acetic acid, corresponding to a yield of 87% based on its cell dry weight. The dry cell weight increased from 0.71 to 1.67 g/L. On the other hand, using concentrated rubber latex effluent containing acetic and propionic acids resulted in reduced PHA content by dry weight (14%) but the dry cell weight increased from 0.49 to 1.30 g/L. The results clearly indicated that the cells grow well in rubber latex effluent but no PHA was accumulated. This could be due to the high concentration of propionic acid in culture broth or other factors such as heavy metals. Thus further work is required before rubber latex effluent can be utilized as a substrate for PHA production industrially.
    Matched MeSH terms: Calcium Compounds
  12. Mohd Isha NS, Mohd Kusin F, Ahmad Kamal NM, Syed Hasan SNM, Molahid VLM
    Environ Geochem Health, 2021 May;43(5):2065-2080.
    PMID: 33392897 DOI: 10.1007/s10653-020-00784-z
    This paper attempts to evaluate the mineralogical and chemical composition of sedimentary limestone mine waste alongside its mineral carbonation potential. The limestone mine wastes were recovered as the waste materials after mining and crushing processes and were analyzed for mineral, major and trace metal elements. The major mineral composition discovered was calcite (CaCO3) and dolomite [CaMg(CO3)2], alongside other minerals such as bustamite [(Ca,Mn)SiO3] and akermanite (Ca2MgSi2O7). Calcium oxide constituted the greatest composition of major oxide components of between 72 and 82%. The presence of CaO facilitated the transformation of carbon dioxide into carbonate form, suggesting potential mineral carbonation of the mine waste material. Geochemical assessment indicated that mean metal(loid) concentrations were found in the order of Al > Fe > Sr > Pb > Mn > Zn > As > Cd > Cu > Ni > Cr > Co in which Cd, Pb and As exceeded some regulatory guideline values. Ecological risk assessment demonstrated that the mine wastes were majorly influenced by Cd as being classified having moderate risk. Geochemical indices depicted that Cd was moderately accumulated and highly enriched in some of the mine waste deposited areas. In conclusion, the limestone mine waste material has the potential for sequestering CO2; however, the presence of some trace metals could be another important aspect that needs to be considered. Therefore, it has been shown that limestone mine waste can be regarded as a valuable feedstock for mineral carbonation process. Despite this, the presence of metal(loid) elements should be of another concern to minimize potential ecological implication due to recovery of this waste material.
    Matched MeSH terms: Calcium Compounds/analysis; Calcium Compounds/chemistry
  13. Radzali, O., Zaleha, M., Nor Fatiha, I., Ooi, C.H.
    MyJurnal
    Glass-ceramics are a group of materials that takes advantage of the various glass-forming methods before they are subsequently heat-treated in a controlled manner to effect nucleation and crystallization to produce crystalline materials. The production of glassceramic materials is to overcome the low mechanical strength in pure glassy materials. In this work, a study on the crystallisation of a soda-lime-silica glass was undertaken to ascertain how the processing parameters affect the crystallization of such glasses, viz. either via a single or two-step heat-treatment procedure, as well as the effect of soaking duration at the heat-treatment temperature. A soda-lime-silica glass system was chosen because the raw materials for producing such glasses are readily available and can be considered to be the cheapest. The glass produced was examined by thermal analysis to determine the nucleation and crystallization temperatures before they were heat-treated using a single-step and a two-stage heat-treatment procedures. The resultant glassceramics produced were characterized using x-ray diffraction as well as by scanning electron microscopy. The results thus obtained showed that a two-stage heat-treatment procedure is more successful in producing a well-crystallized glass-ceramic product.
    Matched MeSH terms: Calcium Compounds
  14. Islam R, Toida Y, Chen F, Tanaka T, Inoue S, Kitamura T, et al.
    Int Endod J, 2021 Oct;54(10):1902-1914.
    PMID: 34096634 DOI: 10.1111/iej.13587
    AIM: To evaluate the dental pulp response to a novel mineral trioxide aggregate containing phosphorylated pullulan (MTAPPL) in rats after direct pulp capping.

    METHODS: Ninety-six cavities were prepared in the maxillary first molars of 56 male Wistar rats. The dental pulps were intentionally exposed and randomly divided into four groups according to the application of pulp capping materials: MTAPPL; phosphorylated pullulan (PPL); a conventional MTA (Nex-Cem MTA, NCMTA; positive control); and Super-Bond (SB; negative control). All cavities were restored with SB and observed for pulpal responses at 1-, 3-, 7- and 28-day intervals using a histological scoring system. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U-test with Bonferroni's correction, and the level of significance was set at 0.05. DMP1 and CD34 antigen were used to evaluate odontoblast differentiation and pulpal vascularization, respectively.

    RESULTS: On day 1, mild inflammatory cells were present in MTAPPL and NCMTA groups; fewer inflammatory cells were present in the PPL, whereas SB was associated with a mild-to-moderate inflammatory response. A significant difference was observed between PPL and SB (p  .05). SB exhibited incomplete mineralized tissue barriers, significantly different from NCMTA, MTAPPL and PPL (p 

    Matched MeSH terms: Calcium Compounds
  15. Velu, S., Abu Bakar, F., Saari, N., Zaman, M.Z., Mahyudin, N.A.
    MyJurnal
    The demand for novel antimicrobial agents from natural resources has been increased worldwide for food conservation purpose. In this study antimicrobial activity of musk lime, key lime and lemon were evaluated against various food borne pathogens and spoilage bacteria using disc diffusion test. Type of extraction solvent and concentration level significantly influenced the antibacterial activity of all the extracts. Ethanol extracts of musk lime, key lime and lemon exhibited significant broadest inhibitory activity at 100% concentration level (pure extract) compared to water and juice extracts. 100% ethanol extracts of musk lime (39.7 mm), key lime (26.7 mm) and lemon (32.0 mm) exhibited the largest diameter of inhibition zone (DIZ) against Aeromonas veronii. 100% water extracts of musk lime (25.3 mm), key lime juice extract (23.3 mm) and water extracts of lemon (23.7 mm) was most effective against food spoilage bacteria, A. veronii. The prominent results of the antimicrobial activity from lime, key lime and lemon extracts may attribute them as potential natural food preservatives and could be used in pharmaceuticals field.
    Matched MeSH terms: Calcium Compounds
  16. Lim, S.M., Loh, S.P.
    MyJurnal
    This study aims to determine the antioxidant capacities (AC) and antidiabetic properties of
    phenolic extracts (free and bound) from white Tambun pomelo peels, kaffir lime peels, lime
    peels and calamansi peels. AC, total phenolic content (TPC) and antidiabetic properties of
    selected citrus peels extracts were determined spectrophotometrically using 2,2-Diphenyl-1-
    picrylhydrazyl free radical (DPPH) scavenging, ferric-reducing antioxidant power (FRAP),
    Folin-Ciocalteu (FC) and α-amylase and α-glucosidase inhibition assay, respectively. This
    study found that the methanolic extract of kaffir lime showed the best AC with the lowest
    IC50 value of DPPH radical (7.51 ± 0.50 mg/ml) and highest FRAP value [369.48 ± 20.15
    mM Fe (II) E/g DW]. TPC of free phenolic extracts of all citrus peels were significantly (p<
    0.05) higher compared to the bound phenolic extracts with extract of calamansi showed the
    highest TPC. Free- and bound phenolic extract of calamansi also had the highest α-amylase
    inhibition activity (61.79 ± 4.13%; 45.30 ± 5.35%) respectively. The highest inhibitory effect in
    α-glucosidase inhibition assay of free- and bound phenolic extracts were white Tambun pomelo
    (41.06 ± 10.94%) and calamansi (43.99 ± 22.03%) respectively. Hence, the citrus peels could
    be furthered study for their potential in management and/or prevention of diabetes.
    Matched MeSH terms: Calcium Compounds
  17. Kaniraj, Shenbaga R., Fung, Y. C.
    MyJurnal
    Addition of chemical binders such as lime and cement improves the strength and stiffness
    of fine grained soils. However, the treated soils exhibit brittle stress-strain behaviour.
    Inclusion of randomly oriented discrete fibers in the soil-binder mixture changes its brittle
    behaviour into ductile behaviour. Most synthetic fibers, however, tend to get entangled
    and cannot be easily separated from one another. Therefore, it is difficult to realize soilbinder-
    fiber mixtures in which the fibers are distributed uniformly throughout the mass.
    This issue has been an impediment in the utilization of the positive modification in the
    behaviours of soils and soil-binder mixtures by the fibers. The present study aims to address
    the limitations in using fibers as soil reinforcement. Further, it also aims to investigate
    the use of synthetic mesh or net elements as an alternative type of soil reinforcement.
    The paper presents the experimental study on a fine grained soil. Lime has been chosen
    as the binder due to its low cost and the scarcity of fiber reinforced soil studies in which
    lime has been used as a binder. The main experimental program is a series of unconfined
    compression tests on samples prepared using untreated soil, soil-reinforcement mixture,
    soil-lime mixture, and soil-lime-reinforcement mixture. The lime treated samples were
    cured up to 120 days at laboratory temperature. The results demonstrate the combinational
    effects of lime and discrete reinforcement
    elements on the behaviour and mechanical
    properties of the soil. The performances of
    the fiber and mesh element reinforcements
    have also been compared.
    Matched MeSH terms: Calcium Compounds
  18. Smran A, Abdullah M, Ahmad NA, Alrahlah A, Al-Maflehi N, Samran A
    BMC Oral Health, 2023 Sep 18;23(1):673.
    PMID: 37723511 DOI: 10.1186/s12903-023-03377-1
    BACKGROUND: The aim of this study was to evaluate the effect of thermal and mechanical cyclic aging using a mastication simulator on push-out bond strength of mandibular premolars obturated with AH Plus and BioRoot RCS root canal sealers.

    METHODS: With REVO-S files up to SU/0.06 taper, 48 single-rooted premolar teeth were instrumented. The teeth were randomly divided into two main groups (n = 24) based on the two root canal sealers used (AH Plus and BioRoot RCS). All teeth were obturated with h matched-taper single-cone. Each main group was then subdivided into three subgroups (A, B, and C) (n = 8). Group A served as the negative control group (no-thermocycling aging). While groups B and C were subjected to thermal changes in a thermocycler machine (15,000 and 30,000 thermal cycles, respectively), followed by two different dynamic loading periods, 3 × 105 and 6 × 105 in a masticatory simulator with a nominal load of 5 kg at 1.2 Hz which represent roughly 1½ and 3 years of clinical function respectively. 2 mm slice at 3 levels, apical, middle, and coronal, to obtain 3 sections were prepared and subjected to push-out test using a universal testing machine. Statistical analysis was performed using analysis of variance (ANOVA) followed by a Tukey post hoc comparisons test and an independent T-test. A significance level of 5% was used.

    RESULTS: After thermal-mechanical cyclic aging, the two root canal sealers showed a significantly decreased in push-out bond strength (p 

    Matched MeSH terms: Calcium Compounds
  19. Sofia Beagem Mohd Noal, Roslinda Shamsudin, Tan, Lee Phin, Wan Khartini Wan Abdul Khodir
    MyJurnal
    Hydroxyapatite (HA) powder was synthesized via wet method using calcium nitrate hydrate (Ca(NO3)2.H2O) and diammonium hydrogen phosphate ((NH4)2HPO4) as raw materials. Powder obtained was milled using various milling speed ranging from 250 to 400 r.p.m. and sintered at 1300°C for 2hrs. Due to the nature of HA powder that decomposed at high temperature, XRD technique have been used in this work to determine the phase composition of the HA powder and also the crystallite size. The unmilled sample was used as the control group. Results show that sufficient heat supply generated from the milling process, initiates the decomposition of HA phase into ȕ-tricalcium phosphate (ȕ-TCP). Decomposition of HA starts to occur at the milling speed of 300 rpm, i.e the formation of ȕ-TCP was occurred at lower sintering temperature. It was believed that the decomposition of HA was associated with the formation of an intermediate phase, oxyapatite. Moreover, the crystallinity and particle size of the produced powder is very much affected by the milling speed and the stability of the HA. All milled powders possess spherical shape particle.
    Matched MeSH terms: Calcium Compounds
  20. Yatongchai C, Placek LM, Curran DJ, Towler MR, Wren AW
    J Biomater Appl, 2015 Nov;30(5):495-511.
    PMID: 26116020 DOI: 10.1177/0885328215592866
    Hydroxyapatite (Ca10(PO4)6(OH)2) is widely investigated as an implantable material for hard tissue restoration due to its osteoconductive properties. However, hydroxyapatite in bulk form is limited as its mechanical properties are insufficient for load-bearing orthopedic applications. Attempts have been made to improve the mechanical properties of hydroxyapatite, by incorporating ceramic fillers, but the resultant composite materials require high sintering temperatures to facilitate densification, leading to the decomposition of hydroxyapatite into tricalcium phosphate, tetra-calcium phosphate and CaO phases. One method of improving the properties of hydroxyapatite is to incorporate bioactive glass particles as a second phase. These typically have lower softening points which could possibly facilitate sintering at lower temperatures. In this work, a bioactive glass (SiO2-CaO-ZnO-Na2O-TiO2) is incorporated (10, 20 and 30 wt%) into hydroxyapatite as a reinforcing phase. X-ray diffraction confirmed that no additional phases (other than hydroxyapatite) were formed at a sintering temperature of 560 ℃ with up to 30 wt% glass addition. The addition of the glass phase increased the % crystallinity and the relative density of the composites. The biaxial flexural strength increased to 36 MPa with glass addition, and there was no significant change in hardness as a function of maturation. The pH of the incubation media increased to pH 10 or 11 through glass addition, and ion release profiles determined that Si, Na and P were released from the composites. Calcium phosphate precipitation was encouraged in simulated body fluid with the incorporation of the bioactive glass phase, and cell culture testing in MC-3T3 osteoblasts determined that the composite materials did not significantly reduce cell viability.
    Matched MeSH terms: Calcium Compounds/chemistry*
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