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Fulltext STUDY ON AQUEOUS KAFFIR LIME EXTRACT AS TREATMENT AGENT ON FRESH TOMATO FRUITS

NUR FAZLEEN SYUHADA ROSTAM, NOR AMIRA IZATI NOR AZMAN, NURUL FAZIHA IBRAHIM, SUHAIZAN LOB

UMT Journal of Undergraduate Research, 2020;2(4):17-22.
MyJurnal

Tomatoes have a short shelf life thus they pose a big challenge for growers to maintain the quality of tomatoes to increase customer acceptance. In this study, fungi associated with tomato disease symptoms were isolated and the potential of kaffir lime aqueous extract was evaluated in maintaining post-harvest quality of tomatoes. For this purpose, healthy tomatoes were dipped in 10% aqueous kaffir lime extract before evaluating the post-harvest parameters namely weight loss and firmness. A fungus namely Rhizophus stolonifer was isolated from the symptomatic tomatoes. Subsequently, it was confirmed to be pathogenic on healthy tomato fruits with 100% disease severity. Application of aqueous kaffir lime extract showed that tomato fruits dipped in 10% aqueous kaffir lime extract recorded higher weight loss and higher firmness as compared to untreated tomato fruits. The results showed that treatment with this concentration of plant extract did not help to reduce the weight loss, but it retained the firmness of the tomato fruits stored at room temperature at 27+2oC. Higher transpiration process would lead to shrinkage, weight loss, changes in texture and appearance of the fruits. Therefore, this study suggested an increased concentration of aqueous kaffir lime extract as a treatment agent in order to have a better effect in maintaining the quality of tomato fruits.

Matched MeSH terms: Calcium Compounds
Fulltext Endophytic Bacteria Isolated from Citrus Plants for Biological Control of Citrus Canker in Lime Plants

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
Fulltext A comparison in mechanical properties of cermets of calcium silicate with Ti-55Ni and Ti-6Al-4V alloys for hard tissues replacement

Ataollahi Oshkour A, Pramanik S, Shirazi SF, Mehrali M, Yau YH, Abu Osman NA

ScientificWorldJournal, 2014;2014:616804.
PMID: 25538954 DOI: 10.1155/2014/616804

This study investigated the impact of calcium silicate (CS) content on composition, compressive mechanical properties, and hardness of CS cermets with Ti-55Ni and Ti-6Al-4V alloys sintered at 1200°C. The powder metallurgy route was exploited to prepare the cermets. New phases of materials of Ni16Ti6Si7, CaTiO3, and Ni31Si12 appeared in cermet of Ti-55Ni with CS and in cermet of Ti-6Al-4V with CS, the new phases Ti5Si3, Ti2O, and CaTiO3, which were emerged during sintering at different CS content (wt%). The minimum shrinkage and density were observed in both groups of cermets for the 50 and 100 wt% CS content, respectively. The cermets with 40 wt% of CS had minimum compressive Young's modulus. The minimum of compressive strength and strain percentage at maximum load were revealed in cermets with 50 and 40 wt% of CS with Ti-55Ni and Ti-6Al-4V cermets, respectively. The cermets with 80 and 90 wt% of CS showed more plasticity than the pure CS. It concluded that the composition and mechanical properties of sintered cermets of Ti-55Ni and Ti-6Al-4V with CS significantly depend on the CS content in raw cermet materials. Thus, the different mechanical properties of the cermets can be used as potential materials for different hard tissues replacements.

Matched MeSH terms: Calcium Compounds/chemistry*
Efficacy of Biodentine and Mineral Trioxide Aggregate in Primary Molar Pulpotomies-A Systematic Review and Meta-Analysis With Trial Sequential Analysis of Randomized Clinical Trials

Nagendrababu V, Pulikkotil SJ, Veettil SK, Jinatongthai P, Gutmann JL

J Evid Based Dent Pract, 2019 03;19(1):17-27.
PMID: 30926099 DOI: 10.1016/j.jebdp.2018.05.002

OBJECTIVES: Pulpotomy is the favored treatment for pulp exposure in carious primary teeth. This review aimed to compare the success rates of biodentine (BD) and mineral trioxide aggregate (MTA) pulpotomies in primary molars using meta-analysis (MA) and trial sequential analysis (TSA) and also to assess the quality of the results by Grading of Recommendations, Assessment, Development and Evaluation (GRADE).
METHODS: PubMed, EBSCOhost, and Scopus databases were searched. Additional searching was performed in clinical trial registry, reference lists of systematic reviews, and textbooks. Randomized clinical trials (RCTs) published in the English language through October 2017 comparing the success of pulpotomies in vital primary molars with a follow-up of at least 6 months were selected. Study selection, data extraction, and risk of bias assessment were performed. MA by random effects model, TSA, and GRADE were performed.
RESULTS: Eight RCTs (n = 474) were included. Two RCTs had low risk of bias. No significant difference was observed between MTA and BD in clinical success at 6 months (risk ratio [RR], 1.00; 95% confidence interval [95% CI], 0.97-1.02; I2 = 0%), 12 months (RR, 1.00; 95% CI, 0.96-1.05; I2 = 0%), and 18 months (RR, 1.00; 95% CI, 0.93-1.08; I2 = 0%). No difference was observed in radiographic success at follow-up of 6 months (RR, 0.99; 95% CI, 0.96-1.02; I2 = 0%), 12 months (RR, 1.02; 95% CI, 0.47-2.21; I2 = 0%), and 18 months (RR, 1.02; 95% CI, 0.91-1.15; I2 = 0%). TSA indicated lack of firm evidence for the results of the meta-analytic outcomes on clinical and radiographic success. GRADE assessed the evidence from the MA comparing the effect of MTA and BD in pulpotomy to be of low quality.
CONCLUSION: BD and MTA have similar clinical and radiographic success rates based on limited and low-quality evidence. Future high-quality RCTs between MTA and BD is required to confirm the evidence.

Matched MeSH terms: Calcium Compounds
Effect of Intracanal Medicaments on the Bond Strength of Bioceramic Root Filling Materials to Oval Canals

Al-Haddad AY, Kacharaju KR, Haw LY, Yee TC, Rajantheran K, Mun CS, et al.

J Contemp Dent Pract, 2020 Nov 01;21(11):1218-1221.
PMID: 33850066

AIM: This study aimed to evaluate the effect of the prior application of intracanal medicaments on the bond strength of OrthoMTA (mineral trioxide aggregate) and iRoot SP to the root dentin.
MATERIALS AND METHODS: Thirty single-rooted mandibular premolars were standardized and prepared using ProTaper rotary files. The specimens were divided into a control group and two experimental groups receiving Diapex and Odontopaste medicament, either filled with iRoot SP or OrthoMTA, for 1 week. Each root was sectioned transversally, and the push-out bond strength and failure modes were evaluated. The data were analyzed using Kruskal Wallis and Mann-Whitney U post hoc test.
RESULTS: There was no significant difference between the bond strength of iRoot SP and OrthoMTA without medicaments and with the prior placement of Diapex (p value > 0.05). However, iRoot SP showed significantly higher bond strength with the prior placement of Odontopaste (p value < 0.05). Also, there was no association between bond strength of OrthoMTA with or without intracanal medicament (p value > 0.05) and between failure mode and root filling materials (p value > 0.05). The prominent failure mode for all groups was cohesive.
CONCLUSION: Prior application of Diapex has no effect on the bond strength of iRoot SP and OrthoMTA. However, Odontopaste improved the bond strength of iRoot SP.
CLINICAL SIGNIFICANCE: Dislodgment resistance of root canal filling from root dentin could be an indicator of the durability and prognosis of endodontic treated teeth.

Matched MeSH terms: Calcium Compounds
Facile synthesis of CaFe2O4 for visible light driven treatment of polluting palm oil mill effluent: Photokinetic and scavenging study

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
Exposure to Pb-halide perovskite nanoparticles can deliver bioavailable Pb but does not alter endogenous gut microbiota in zebrafish

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
Fulltext Cytotoxicity of accelerated white MTA and Malaysian white Portland cement on stem cells from human exfoliated deciduous teeth (SHED): An in vitro study

Ong RM, Luddin N, Ahmed HM, Omar NS

Singapore Dent J, 2012 Dec;33(1):19-23.
PMID: 23739319 DOI: 10.1016/j.sdj.2012.11.001

The aim of this study was to compare the cytotoxicity of accelerated-set white MTA (AWMTA) and accelerated-set Malaysian white PC (AMWPC) on stem cells from human exfoliated deciduous teeth (SHED). The test materials were introduced into paraffin wax moulds after mixing with calcium chloride dihydrate and sterile distilled water. Subsequently, the set cement specimens were sterilized, incubated in a prepared Dulbecco's modified Eagle medium (DMEM) for seven days. The biomarker CD166 was used for characterization of SHED using flow cytometry. The material extracts were diluted at five different concentrations and incubated for 72h with SHED. The cell viability was evaluated using Dimethylthiazol diphenyltetrazolium bromide (MTT) assay, and the data was analysed using Mann-Whitney test (P<0.05). The results showed that AWMTA revealed significantly greater cell viability at 25 and 12.5mg/ml concentrations (P<0.05). Concomitantly, AMWPC exhibited greater cell viability at concentrations <12.5mg/ml and the results were significant at 1.563mg/ml (P<0.05). Both materials demonstrated moderate cytotoxicity at 25mg/ml and slight cytotoxicity at 6.25 and 3.125mg/ml. At 1.563mg/ml, no cytotoxic activity was merely observed with AMWPC. In conclusion, AMWPC exhibited favourable and comparable cell viability to that of AWMTA, and has the potential to be used as an alternative and less costly material in dental applications.

Matched MeSH terms: Calcium Compounds
Fulltext Design and Development for Capacitive Humidity Sensor Applications of Lead-Free Ca,Mg,Fe,Ti-Oxides-Based Electro-Ceramics with Improved Sensing Properties via Physisorption

Tripathy A, Pramanik S, Manna A, Bhuyan S, Azrin Shah NF, Radzi Z, et al.

Sensors (Basel), 2016 Jul 21;16(7).
PMID: 27455263 DOI: 10.3390/s16071135

Despite the many attractive potential uses of ceramic materials as humidity sensors, some unavoidable drawbacks, including toxicity, poor biocompatibility, long response and recovery times, low sensitivity and high hysteresis have stymied the use of these materials in advanced applications. Therefore, in present investigation, we developed a capacitive humidity sensor using lead-free Ca,Mg,Fe,Ti-Oxide (CMFTO)-based electro-ceramics with perovskite structures synthesized by solid-state step-sintering. This technique helps maintain the submicron size porous morphology of the developed lead-free CMFTO electro-ceramics while providing enhanced water physisorption behaviour. In comparison with conventional capacitive humidity sensors, the presented CMFTO-based humidity sensor shows a high sensitivity of up to 3000% compared to other materials, even at lower signal frequency. The best also shows a rapid response (14.5 s) and recovery (34.27 s), and very low hysteresis (3.2%) in a 33%-95% relative humidity range which are much lower values than those of existing conventional sensors. Therefore, CMFTO nano-electro-ceramics appear to be very promising materials for fabricating high-performance capacitive humidity sensors.

Matched MeSH terms: Calcium Compounds
Fulltext Stable and null current hysteresis perovskite solar cells based nitrogen doped graphene oxide nanoribbons hole transport layer

Kim J, Mat Teridi MA, Mohd Yusoff AR, Jang J

Sci Rep, 2016 06 09;6:27773.
PMID: 27277388 DOI: 10.1038/srep27773

Perovskite solar cells are becoming one of the leading technologies to reduce our dependency on traditional power sources. However, the frequently used component poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (
PEDOT: PSS) has several shortcomings, such as an easily corroded indium-tin-oxide (ITO) interface at elevated temperatures and induced electrical inhomogeneity. Herein, we propose solution-processed nitrogen-doped graphene oxide nanoribbons (NGONRs) as a hole transport layer (HTL) in perovskite solar cells, replacing the conducting polymer
PEDOT: PSS. The conversion efficiency of NGONR-based perovskite solar cells has outperformed a control device constructed using
PEDOT: PSS. Moreover, our proposed NGONR-based devices also demonstrate a negligible current hysteresis along with improved stability. This work provides an effective route for substituting
PEDOT: PSS as the effective HTL.

Matched MeSH terms: Calcium Compounds
Fulltext WS2: A New Window Layer Material for Solar Cell Application

Bin Rafiq MKS, Amin N, Alharbi HF, Luqman M, Ayob A, Alharthi YS, et al.

Sci Rep, 2020 Jan 21;10(1):771.
PMID: 31964954 DOI: 10.1038/s41598-020-57596-5

Radio frequency (RF) magnetron sputtering was used to deposit tungsten disulfide (WS2) thin films on top of soda lime glass substrates. The deposition power of RF magnetron sputtering varied at 50, 100, 150, 200, and 250 W to investigate the impact on film characteristics and determine the optimized conditions for suitable application in thin-film solar cells. Morphological, structural, and opto-electronic properties of as-grown films were investigated and analyzed for different deposition powers. All the WS2 films exhibited granular morphology and consisted of a rhombohedral phase with a strong preferential orientation toward the (101) crystal plane. Polycrystalline ultra-thin WS2 films with bandgap of 2.2 eV, carrier concentration of 1.01 × 1019 cm-3, and resistivity of 0.135 Ω-cm were successfully achieved at RF deposition power of 200 W. The optimized WS2 thin film was successfully incorporated as a window layer for the first time in CdTe/WS2 solar cell. Initial investigations revealed that the newly incorporated WS2 window layer in CdTe solar cell demonstrated photovoltaic conversion efficiency of 1.2% with Voc of 379 mV, Jsc of 11.5 mA/cm2, and FF of 27.1%. This study paves the way for WS2 thin film as a potential window layer to be used in thin-film solar cells.

Matched MeSH terms: Calcium Compounds
Fulltext Bandgap tuning of mixed organic cation utilizing chemical vapor deposition process

Kim J, Kim HP, Teridi MA, Yusoff AR, Jang J

Sci Rep, 2016 11 22;6:37378.
PMID: 27874026 DOI: 10.1038/srep37378

Bandgap tuning of a mixed organic cation perovskite is demonstrated via chemical vapor deposition process. The optical and electrical properties of the mixed organic cation perovskite can be manipulated by varying the growth time. A slight shift of the absorption band to shorter wavelengths is demonstrated with increasing growth time, which results in the increment of the current density. Hence, based on the optimized growth time, our device exhibits an efficiency of 15.86% with negligible current hysteresis.

Matched MeSH terms: Calcium Compounds
Fulltext Tunable Open Circuit Voltage by Engineering Inorganic Cesium Lead Bromide/Iodide Perovskite Solar Cells

Ng CH, Ripolles TS, Hamada K, Teo SH, Lim HN, Bisquert J, et al.

Sci Rep, 2018 02 06;8(1):2482.
PMID: 29410450 DOI: 10.1038/s41598-018-20228-0

Perovskite solar cells based on series of inorganic cesium lead bromide and iodide mixture, CsPbBr3-xI x , where x varies between 0, 0.1, 0.2, and 0.3 molar ratio were synthesized by two step-sequential deposition at ambient condition to design the variations of wide band gap light absorbers. A device with high overall photoconversion efficiency of 3.98 % was obtained when small amount of iodide (CsPbBr2.9I0.1) was used as the perovskite and spiro-OMeTAD as the hole transport material (HTM). We investigated the origin of variation in open circuit voltage, Voc which was shown to be mainly dependent on two factors, which are the band gap of the perovskite and the work function of the HTM. An increment in Voc was observed for the device with larger perovskite band gap, while keeping the electron and hole extraction contacts the same. Besides, the usage of bilayer P3HT/MoO3 with deeper HOMO level as HTM instead of spiro-OMeTAD, thus increased the Voc from 1.16 V to 1.3 V for CsPbBr3 solar cell, although the photocurrent is lowered due to charge extraction issues. The stability studies confirmed that the addition of small amount of iodide into the CsPbBr3 is necessarily to stabilize the cell performance over time.

Matched MeSH terms: Calcium Compounds
Fulltext SrCo1-xTixO3-δ perovskites as excellent catalysts for fast degradation of water contaminants in neutral and alkaline solutions

Miao J, Sunarso J, Su C, Zhou W, Wang S, Shao Z

Sci Rep, 2017 03 10;7:44215.
PMID: 28281656 DOI: 10.1038/srep44215

Perovskite-like oxides SrCo1-xTixO3-δ (SCTx, x = 0.1, 0.2, 0.4, 0.6) were used as heterogeneous catalysts to activate peroxymonosulfate (PMS) for phenol degradation under a wide pH range, exhibiting more rapid phenol oxidation than Co3O4 and TiO2. The SCT0.4/PMS system produced a high activity at increased initial pH, achieving optimized performance at pH ≥ 7 in terms of total organic carbon removal, the minimum Co leaching and good catalytic stability. Kinetic studies showed that the phenol oxidation kinetics on SCT0.4/PMS system followed the pseudo-zero order kinetics and the rate on SCT0.4/PMS system decreased with increasing initial phenol concentration, decreased PMS amount, catalyst loading and solution temperature. Quenching tests using ethanol and tert-butyl alcohol demonstrated sulfate and hydroxyl radicals for phenol oxidation. This investigation suggested promising heterogeneous catalysts for organic oxidation with PMS, showing a breakthrough in the barriers of metal leaching, acidic pH, and low efficiency of heterogeneous catalysis.

Matched MeSH terms: Calcium Compounds
Fulltext Compositions and antimicrobial properties of binary ZnO-CuO nanocomposites encapsulated calcium and carbon from Calotropis gigantea targeted for skin pathogens

Govindasamy GA, Mydin RBSMN, Sreekantan S, Harun NH

Sci Rep, 2021 01 08;11(1):99.
PMID: 33420110 DOI: 10.1038/s41598-020-79547-w

Calotropis gigantea (C. gigantea) extract with an ecofriendly nanotechnology approach could provide promising antimicrobial activity against skin pathogens. This study investigates the antimicrobial capability of green synthesized binary ZnO-CuO nanocomposites from C. gigantea against non-MDR (Staphylococcus aureus and Escherichia coli) and MDR (Klebsiella pneumoniae, Pseudomonas aeruginosa and methicillin-resistant S. aureus) skin pathogens. Scanning electron microscopy and transmission electron microscopy revealed the size and shape of B3Z1C sample. Results of X-ray powder diffraction, energy-dispersive spectroscopy, FTIR and UV-Vis spectroscopy analyses confirmed the presence of mixed nanoparticles (i.e., zinc oxide, copper oxide, carbon and calcium) and the stabilising phytochemical agents of plant (i.e., phenol and carbonyl). Antimicrobial results showed that carbon and calcium decorated binary ZnO-CuO nanocomposites with compositions of 75 wt% of ZnO and 25 wt% CuO (B3Z1C) was a strong bactericidal agent with the MBC/MIC ratio of ≤ 4 and ≤ 2 for non-MDR and MDR pathogens, respectively. A significant non-MDR zone of inhibitions were observed for BZC by Kirby-Bauer disc-diffusion test. Further time-kill observation revealed significant fourfold reduction in non-MDR pathogen viable count after 12 h study period. Further molecular studies are needed to explain the biocidal mechanism underlying B3Z1C potential.

Matched MeSH terms: Calcium Compounds/pharmacology*; Calcium Compounds/chemistry*
Fulltext Adsorption of sulfur dioxide (SO2) gas using treated rice husk ash (RHA) adsorbent

Nurul Najwa Abd Malek, Rusdin Laiman

Science Letters, 2018;12(1):63-76.
MyJurnal

The aim of this study was to investigate the potential of treated rice husk ash (RHA) as adsorbent to adsorb acidic SO2 gas. The treated RHA was prepared using a water hydration method by mixing the RHA, Calcium oxide (CaO) and Sodium Hydroxide (NaOH). The addition of NaOH is to increase the dissolution of silica from the RHA to form reactive species responsible for higher desulfurization activity. The untreated and treated RHA were subjected to several characterizations and the characteristics of the adsorbents were compared. The functional groups present on the surface of the adsorbent were determined using Fourier Transform Infrared (FTIR). The chemical composition of the untreated and treated RHA was analyzed by using X-ray Fluorescence (XRF). Scanning electron microscope (SEM) analysis showed that the treated RHA has higher porosity compared to untreated RHA. Based on the SO2 adsorption analysis, it was found that the treated RHA has higher adsorption capacity, 62.22 mg/g, compared to untreated RHA, 1.49 mg/g.

Matched MeSH terms: Calcium Compounds
Investigation of trace inorganic elements in street doses of heroin

Chan KW, Tan GH, Wong RC

Sci Justice, 2013 Mar;53(1):73-80.
PMID: 23380066 DOI: 10.1016/j.scijus.2012.08.004

Sixteen trace elements found in 309 street heroin samples, piped water and contaminated water were determined using inductively coupled plasma-mass spectrometry. All the street heroin samples were found to contain high levels of sodium, a reflection of the use of sodium bicarbonate during heroin synthesis. Additionally, this element was also found to be one of the potential contaminants acquired from the piped water. Calcium could be derived from lime while iron, aluminum and zinc could have come from the metallic container used in the processing/cutting stage. The levels of these elements remained low in the heroin and it could be due to the dilution effects from the addition of adulterants. Statistical validation was performed with six links of related heroin samples using principal component analysis to find the best pretreatment for sample classification. It was obtained that normalization followed by fourth root showed promising results with 8% errors in the sample clustering. The technique was then applied to the case samples. Finally, the result suggested that the case samples could have originated from at least two major groups respectively showing unique elemental profiles at the street level.

Matched MeSH terms: Calcium Compounds
Effect of annealing temperature on the microstructure and dielectric properties of Ba0.6Sr0.4TiO3 Ttin films prepared by sol-gel process

Dewi R, Ibrahim N, Talib I, Ibarahim Z

Sains Malaysiana, 2008;37:233-237.

Thin films of barium strontium titanate (Ba0.6Sr0.4TiO3) perovskite system are promising candidates for microelectronic devices that can be integrated with semiconductor technology. Ba0.6Sr0.4TiO3 thin films have been prepared onto BST/TiO2/RuO2/SiO2/Si substrate using the spin coating and sol-gel process. Then the samples were subsequently annealed at 600oC, 650oC and 700oC for 60 minutes in air. The microstructure and dielectric properties show that the crystallization improved as the annealing temperature was increased. All of the films have nanometer grain size. The average grain size of the films increased as the temperature was increased. The dielectric constant and ac conductivity of the films also increased as the average grain size increased. These results showed that the microstructure and dielectric properties depend on the annealing temperature.

Matched MeSH terms: Calcium Compounds
Fulltext Mechanical and in vitro biological performance of graphene nanoplatelets reinforced calcium silicate composite

Mehrali M, Moghaddam E, Seyed Shirazi SF, Baradaran S, Mehrali M, Latibari ST, et al.

PLoS One, 2014;9(9):e106802.
PMID: 25229540 DOI: 10.1371/journal.pone.0106802

Calcium silicate (CaSiO3, CS) ceramic composites reinforced with graphene nanoplatelets (GNP) were prepared using hot isostatic pressing (HIP) at 1150°C. Quantitative microstructural analysis suggests that GNP play a role in grain size and is responsible for the improved densification. Raman spectroscopy and scanning electron microscopy showed that GNP survived the harsh processing conditions of the selected HIP processing parameters. The uniform distribution of 1 wt.% GNP in the CS matrix, high densification and fine CS grain size help to improve the fracture toughness by ∼130%, hardness by ∼30% and brittleness index by ∼40% as compared to the CS matrix without GNP. The toughening mechanisms, such as crack bridging, pull-out, branching and deflection induced by GNP are observed and discussed. The GNP/CS composites exhibit good apatite-forming ability in the simulated body fluid (SBF). Our results indicate that the addition of GNP decreased pH value in SBF. Effect of addition of GNP on early adhesion and proliferation of human osteoblast cells (hFOB) was measured in vitro. The GNP/CS composites showed good biocompatibility and promoted cell viability and cell proliferation. The results indicated that the cell viability and proliferation are affected by time and concentration of GNP in the CS matrix.

Matched MeSH terms: Calcium Compounds/chemistry*
Fulltext Effect of Tricalcium Magnesium Silicate Coating on the Electrochemical and Biological Behavior of Ti-6Al-4V Alloys

Maleki-Ghaleh H, Hafezi M, Hadipour M, Nadernezhad A, Aghaie E, Behnamian Y, et al.

PLoS One, 2015;10(9):e0138454.
PMID: 26383641 DOI: 10.1371/journal.pone.0138454

In the current study, a sol-gel-synthesized tricalcium magnesium silicate powder was coated on Ti-6Al-4V alloys using plasma spray method. Composition of feed powder was evaluated by X-ray diffraction technique before and after the coating process. Scanning electron microscopy and atomic force microscopy were used to study the morphology of coated substrates. The corrosion behaviors of bare and coated Ti-6Al-4V alloys were examined using potentiodynamic polarization test and electrochemical impedance spectroscopy in stimulated body fluids. Moreover, bare and coated Ti-6Al-4V alloys were characterized in vitro by culturing osteoblast and mesenchymal stem cells for several days. Results demonstrated a meaningful improvement in the corrosion resistance of Ti-6Al-4V alloys coated with tricalcium magnesium silicate compared with the bare counterparts, by showing a decrease in corrosion current density from 1.84 μA/cm2 to 0.31 μA/cm2. Furthermore, the coating substantially improved the bioactivity of Ti-6Al-4Valloys. Our study on corrosion behavior and biological response of Ti-6Al-4V alloy coated by tricalcium magnesium silicate proved that the coating has considerably enhanced safety and applicability of Ti-6Al-4V alloys, suggesting its potential use in permanent implants and artificial joints.

Matched MeSH terms: Calcium Compounds/chemistry*

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