Displaying publications 81 - 100 of 148 in total

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  1. Chow MC, Ma AN
    PMID: 17645207
    Microwave heating was determined in this study to be suitable for the detachment and drying of palm fruits from whole bunches, cut bunches and spikelets. Microwave treatment of the palm fruits was able to attain the objectives of conventional fresh palm fruits sterilization processeses such as fruit softening, nut conditioning and halting of enzymatic lipolysis. Palm oil and kernel oil solvent extracted respectively from the microwave treated whole fruits and kernel were found to have a good quality of low free fatty acid content. This technology, together with the solvent extraction of the dehydrated fruits, may have the potential to be a continuous, dry and clean technology for palm oil milling.
    Matched MeSH terms: Heating/methods*
  2. Seow EK, Tan TC, Lee LK, Easa AM
    J Texture Stud, 2020 12;51(6):909-916.
    PMID: 32537814 DOI: 10.1111/jtxs.12544
    Hardening issue in starch-based products that arises during storage, is ascribed to the long-term starch retrogradation which involves the recrystallisation of amylopectin. Present study aimed to delay storage hardening with the addition of high diastase honey bee honey (HBH) and low diastase kelulut bee honey (KBH) into glutinous rice flour (GRF) gels. As compared to KBH, retardation of texture deterioration by HBH was more prominent as evidenced by the significantly (p 
    Matched MeSH terms: Heating*
  3. Noroozi M, Radiman S, Zakaria A, Soltaninejad S
    Nanoscale Res Lett, 2014;9(1):645.
    PMID: 25489293 DOI: 10.1186/1556-276X-9-645
    Silver nanoparticles were successfully prepared in two different solvents using a microwave heating technique, with various irradiation times. The silver nanoparticles were dispersed in polar liquids (distilled water and ethylene glycol) without any other reducing agent, in the presence of the stabilizer polyvinylpyrrolidone (PVP). The optical properties, thermal properties, and morphology of the synthesized silver particles were characterized using ultraviolet-visible spectroscopy, photopyroelectric technique, and transmission electron microscopy. It was found that for the both solvents, the effect of microwave irradiation was mainly on the particles distribution, rather than the size, which enabled to make stable and homogeneous silver nanofluids. The individual spherical nanostructure of self-assembled nanoparticles has been formed during microwave irradiation. Ethylene glycol solution, due to its special properties, such as high dielectric loss, high molecular weight, and high boiling point, can serve as a good solvent for microwave heating and is found to be a more suitable medium than the distilled water. A photopyroelectric technique was carried out to measure thermal diffusivity of the samples. The precision and accuracy of this technique was established by comparing the measured thermal diffusivity of the distilled water and ethylene glycol with values reported in the literature. The thermal diffusivity ratio of the silver nanofluids increased up to 1.15 and 1.25 for distilled water and ethylene glycol, respectively.
    Matched MeSH terms: Heating
  4. Rusnah M, Andanastuti M, Idris B
    Med J Malaysia, 2004 May;59 Suppl B:158-9.
    PMID: 15468866
    The present paper reports on the influence of sintering temperature on the porosity and strength of porous hydroxyapatite (HA). HA powder was first prepared by the sol-gel precipitation method using calcium hydroxide and ortho-phosporic acid. The fine HA powder, measuring <50 microm was then mixed into a slurry with the addition of binder agent, being a mixture of sago and PVA. A small amount of sodium dodecyl sulphate was also used as a foaming agent. Porous HA samples were then prepared via slip casting technique. The surface morphology of the sintered samples was observed under scanning electron microscopy at 20 kV and the compositions were determined via SEM-EDX. A universal testing machine was used to determine the compaction strength of the sintered samples.
    Matched MeSH terms: Heating
  5. Andrew AM, Zakaria A, Mad Saad S, Md Shakaff AY
    Sensors (Basel), 2016;16(1).
    PMID: 26797617 DOI: 10.3390/s16010031
    In this study, an early fire detection algorithm has been proposed based on low cost array sensing system, utilising off- the shelf gas sensors, dust particles and ambient sensors such as temperature and humidity sensor. The odour or "smellprint" emanated from various fire sources and building construction materials at early stage are measured. For this purpose, odour profile data from five common fire sources and three common building construction materials were used to develop the classification model. Normalised feature extractions of the smell print data were performed before subjected to prediction classifier. These features represent the odour signals in the time domain. The obtained features undergo the proposed multi-stage feature selection technique and lastly, further reduced by Principal Component Analysis (PCA), a dimension reduction technique. The hybrid PCA-PNN based approach has been applied on different datasets from in-house developed system and the portable electronic nose unit. Experimental classification results show that the dimension reduction process performed by PCA has improved the classification accuracy and provided high reliability, regardless of ambient temperature and humidity variation, baseline sensor drift, the different gas concentration level and exposure towards different heating temperature range.
    Matched MeSH terms: Heating
  6. Moh MH, Tang TS, Tan GH
    J Chromatogr Sci, 2001 Dec;39(12):508-12.
    PMID: 11767238
    A simple and sensitive high-performance liquid chromatographic method for the determination of Therminol 66 thermal heating fluid in glycerin and fatty acids is developed. Sample solutions dissolved in methanol-tetrahydrofuran (50:50, v/v) are injected directly into a reversed-phase C18 column and eluted with a methanol and water mixture (88:12, v/v). The concentration of the thermal heating fluid is monitored by fluorescence detection at 257 nm (excitation) and 320 nm (emission). The calibration graph obtained from various concentrations of the thermal heating fluid in the methanol and tetrahydrofuran mixture is linear (correlation coefficient = 0.999), and the limit of detection is 0.01 microg/mL. Spiked glycerin containing 0.1 to 1.0 microg/g of the thermal heating fluid also gives good linearity with a mean recovery of 95.3%. The mean intra- and interassay precision are 1.80-6.51% and 5.71-9.03%, respectively, at the 0.1-microg/g level. The method is simple and does not require any pretreatment step, thus it is ideal for quality assurance purposes.
    Matched MeSH terms: Heating
  7. Ng CH, Lim CW, Teoh SG, Fun HK, Usman A, Ng SW
    Inorg Chem, 2002 Jan 14;41(1):2-3.
    PMID: 11782136
    Treatment of vanadium(V) oxide with an ethanol-concentrated sulfuric acid mixture, followed by the addition of an equimolar amount of beta-alanine and sodium hydroxide, and finally raising the pH to 3.9 with sodium carbonate solution, under continuous heating in a water bath and in the presence of air, leads to the polyionic sodium cyclo-[mu(6)-(sulfato-O,O',O'')tris[mu-(beta-alanine-O,O')-mu-oxo]tris(mu-hydroxo-mu-oxo)hexa[oxovanadium(V)]] sulfate tridecahydrate which crystallizes in the monoclinic P2(1)/n space group [a = 9.5192(4), b = 20.1185(9), c = 22.6174(9) A, beta = 97.011(1) degrees; Z = 4]. The crown-shaped polyoxovanadium(V) cluster cation, with carboxylate-bridging amino acid ligands, has an Anderson structure with two unique capping sulfato ligands. Its structural analysis, together with IR, UV-vis, and preliminary data on its solution properties, is presented.
    Matched MeSH terms: Heating
  8. Ng TYS, Chew TL, Yeong YF, Jawad ZA, Ho CD
    Sci Rep, 2019 10 21;9(1):15062.
    PMID: 31636339 DOI: 10.1038/s41598-019-51460-x
    In recent years, there are increasing interest on applying ultrasonic irradiation for the synthesis of zeolite due to its advantages including remarkable shortened synthesis duration. In this project, the potential of ultrasonic irradiation treatment on the synthesis of zeolite RHO was investigated. Ultrasonic irradiation treatment time was varied from 30 to 120 minutes for the synthesis of zeolite RHO. The zeolite RHO solid samples were characterized with X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and nitrogen adsorption-desorption analysis. The application of ultrasonic irradiation treatment in this study has accelerated the synthesis of zeolite RHO where the synthesis duration has been significantly shortened to 2 days compared to 8 days required by conventional hydrothermal heating without ultrasonic irradiation treatment. Highly crystalline zeolite RHO crystals in truncated octahedron morphology were successfully formed.
    Matched MeSH terms: Heating
  9. Isa IN, Dom SM
    J Vet Med Sci, 2016 Oct 1;78(9):1399-1403.
    PMID: 27211519
    Elevated temperatures can induce changes in red blood cell (RBC), white blood cell (WBC) and platelet (PLT) counts. Ultrasound heating during obstetric scans has the potential to increase body temperature owing to the phenomenon of absorption. We conducted a study to determine the thermal effects of prenatal ultrasound on RBCs, hemoglobin concentration (Hb), WBCs and PLTs in young rabbits. We selected 69 rabbits that were 1 month of age and 73 that were 5 months of age, and allocated them to four groups. The control group consisted of four pregnant does that were allowed to have a full term delivery without any ultrasound exposure. The experimental groups were subjected to one-time ultrasound exposure for 30, 60 and 90 min in the middle of each gestational stage accordingly. RBCs and Hb showed significant reductions in the experimental groups of 1- and 5-month-old rabbits (P<0.05). In addition, WBCs and PLTs yielded significant differences in the 1-month group that were not observed in the 5-month group (P>0.05). The highest values recorded were those of the WBCs of 1-month-old subjects that received 90 min of exposure at the second stage of gestation. The PLTs were the lowest values recorded in 1-month-old subjects following 90 min of ultrasound exposure at the third stage of gestation. These findings suggest that hematological fluctuations during the early stages of postnatal life persisted until 1 month of age and recovered thereafter, as the subjects progressed into adulthood. Therefore, ultrasound heating can cause significant, yet reversible effects on the hematological parameters of rabbits.
    Matched MeSH terms: Heating
  10. Ali G, Nisar J, Iqbal M, Shah A, Abbas M, Shah MR, et al.
    Waste Manag Res, 2019 Aug 13.
    PMID: 31405341 DOI: 10.1177/0734242X19865339
    Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin-1, 10°Cmin-1, 15°Cmin-1 and 20°Cmin-1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats-Redfern) and model free methods (Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats-Redfern, Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman models were found in the ranges 105-148.48 kJmol-1, 99.41-140.52 kJmol-1, 103.67-149.15 kJmol-1 and 99.93-141.25 kJmol-1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.
    Matched MeSH terms: Heating
  11. Singh AK, Hakimi MH, Kumar A, Ahmed A, Abidin NSZ, Kinawy M, et al.
    Sci Rep, 2020 12 17;10(1):22108.
    PMID: 33335176 DOI: 10.1038/s41598-020-78906-x
    A high bituminous shale horizon from the Gurha mine in the Bikaner sub-basin of the Rajasthan District, NW India, was studied using a collection of geochemical and petrological techniques. This study investigated the nature and environmental conditions of the organic matter and its relation to the unconventional oil-shale resources of the bituminous shale. The analyzed shales have high total organic carbon and total sulfur contents, suggesting that these shale sediments were deposited in a paralic environment under reducing conditions. The dominant presence of organic matter derived from phytoplankton algae suggests warm climatic marine environment, with little connection to freshwater enhancing the growth of algae and other microorganisms. The analyzed bituminous shales have high aquatic-derived alginite organic matters, with low Pr/Ph, Pr/n-C17, and Ph/n-C18 ratios. It is classified as Type II oil-prone kerogen, consistent with high hydrogen index value. Considering the maturity indicators of geochemical Tmax (
    Matched MeSH terms: Heating
  12. Reza MS, Ahmed A, Caesarendra W, Abu Bakar MS, Shams S, Saidur R, et al.
    Bioengineering (Basel), 2019 Apr 16;6(2).
    PMID: 30995765 DOI: 10.3390/bioengineering6020033
    To evaluate the possibilities for biofuel and bioenergy production Acacia Holosericea, which is an invasive plant available in Brunei Darussalam, was investigated. Proximate analysis of Acacia Holosericea shows that the moisture content, volatile matters, fixed carbon, and ash contents were 9.56%, 65.12%, 21.21%, and 3.91%, respectively. Ultimate analysis shows carbon, hydrogen, and nitrogen as 44.03%, 5.67%, and 0.25%, respectively. The thermogravimetric analysis (TGA) results have shown that maximum weight loss occurred for this biomass at 357 °C for pyrolysis and 287 °C for combustion conditions. Low moisture content (<10%), high hydrogen content, and higher heating value (about 18.13 MJ/kg) makes this species a potential biomass. The production of bio-char, bio-oil, and biogas from Acacia Holosericea was found 34.45%, 32.56%, 33.09% for 500 °C with a heating rate 5 °C/min and 25.81%, 37.61%, 36.58% with a heating rate 10 °C/min, respectively, in this research. From Fourier transform infrared (FTIR) spectroscopy it was shown that a strong C-H, C-O, and C=C bond exists in the bio-char of the sample.
    Matched MeSH terms: Heating
  13. Nizamuddin S, Qureshi SS, Baloch HA, Siddiqui MTH, Takkalkar P, Mubarak NM, et al.
    Materials (Basel), 2019 Jan 28;12(3).
    PMID: 30696042 DOI: 10.3390/ma12030403
    The process parameters of microwave-induced hydrothermal carbonization (MIHTC) play an important role on the hydrothermal chars (hydrochar) yield. The effect of reaction temperature, reaction time, particle size and biomass to water ratio was optimized for hydrochar yield by modeling using the central composite design (CCD). Further, the rice straw and hydrochar at optimum conditions have been characterized for energy, chemical, structural and thermal properties. The optimum condition for hydrochar synthesis was found to be at a 180 °C reaction temperature, a 20 min reaction time, a 1:15 weight per volume (w/v) biomass to water ratio and a 3 mm particle size, yielding 57.9% of hydrochar. The higher heating value (HHV), carbon content and fixed carbon values increased from 12.3 MJ/kg, 37.19% and 14.37% for rice straw to 17.6 MJ/kg, 48.8% and 35.4% for hydrochar. The porosity, crystallinity and thermal stability of the hydrochar were improved remarkably compared to rice straw after MIHTC. Two characteristic peaks from XRD were observed at 2θ of 15° and 26°, whereas DTG peaks were observed at 50⁻150 °C and 300⁻350 °C for both the materials. Based on the results, it can be suggested that the hydrochar could be potentially used for adsorption, carbon sequestration, energy and agriculture applications.
    Matched MeSH terms: Heating
  14. Choi WC, Parr T, Lim YS
    J Food Sci Technol, 2019 Jan;56(1):281-289.
    PMID: 30728570 DOI: 10.1007/s13197-018-3488-0
    The global trend in increasing plant-based protein diets due to health and ideological reasons, has created an increased demand for food legumes that exceeds current production. To meet this demand, it is timely to reduce relying solely on soybean, and explore the potential of the underutilised legumes that are cultivated regionally. Underutilised legumes are rich in protein, carbohydrates and other nutrients that are essential for consumer. However, relatively little is known about their anti-nutritional properties and processing methods. Anti-nutritional factors (ANFs) such as enzyme inhibitors are prevalent in legumes and may interfere with digestibility and nutrient absorption. Nevertheless, an optimised food processing method will overcome this challenge and warrant a safe inclusion of legume in plant-based protein diets. Hence current study aimed to optimise the food processing methods (soaking, wet heating, autoclaving and freezing) and evaluate their efficiency in eliminating the enzyme inhibitors [trypsin, chymotrypsin (CIA) and α-amylase (AIA) inhibitors] present in seven underutilised legumes. Current study showed that autoclaving at 121 °C for 15 min reduced the AIA in all underutilised legumes tested. The AIA and CIA of bambara groundnut were successfully inactivated by wet heating at 50 °C for 60 min, and by autoclaving at 121 °C for 15 min. While the CIA of chickpea was successfully inactivated by freezing at - 80 °C for 24 h.
    Matched MeSH terms: Heating
  15. Md Dom S, Abdul Razak HR, Ahmad Zaiki FW, Saat NH, Abd Manan K, Che Isa IN, et al.
    Quant Imaging Med Surg, 2013 Feb;3(1):49-53.
    PMID: 23483040 DOI: 10.3978/j.issn.2223-4292.2013.02.06
    The aim of this study was to investigate the changes in parathyroid hormone (PTH) level of rabbit foetal bodies exposed to ultrasound at different gestational stages. A total of 9 pregnant rabbits (Oryctolagus cuniculus) were insonated for 60 minutes at the middle of 1(st), 2(nd) and 3(rd) gestational stages for group A (n=14 newborns), group B (n=7 newborns) and group C (n=24 newborns) respectively. Seven pregnant rabbits with 41 newborns severed as negative control group. Blood samples were withdrawn from each newborn rabbits for Parathyroid Hormone-Intact (PTH-I) test. Results of the independent samples t-test implied statistically significant differences (P<0.05) between the control group and the 1(st) stage (P=0.001), the 2(nd) stage (P<0.001) and the 3(rd) stage group (P<0.001). This in-vivo study revealed diagnostic ultrasound heating has the potential of affecting foetal PTH level. This study observed significantly low PTH level for all the treated groups. A further study should be instituted to determine whether this finding in rabbit may also occur in human by means of clinical trials.
    Matched MeSH terms: Heating
  16. Kuang TK, Kang YB, Segarra I, Kanwal U, Ahsan M, Bukhari NI
    Turk J Pharm Sci, 2021 04 20;18(2):167-175.
    PMID: 33902255 DOI: 10.4274/tjps.galenos.2020.48902
    Objectives: This study was conducted to assess the effect of microwave heating on the preparation of paracetamol cross-linked gelatin matrices by using the design of experiment (DoE) approach and explore the influence of the duration of microwave irradiation, the concentrations of crosslinker, and the amount of sodium bicarbonate (salt) on paracetamol release. These parameters were also compared with those of the matrices prepared via conventional heating.

    Materials and Methods: Twenty gel matrices were prepared with different durations of microwave irradiation, amounts of maize, and concentrations of sodium bicarbonate as suggested by Design Expert (DX®). The percentage drug release, the coefficient of variance (CV) in release, and the mean dissolution time (MDT) were the properties explored in the designed experimentation.

    Results: Target responses were dependent on microwave irradiation time, cross-linker amount, and salt concentration. Classical and microwave heating did not demonstrate statistically significant difference in modifying the percentage of drug released from the matrices. However, the CVs of microwave-assisted formulations were lower than those of the gel matrices prepared via classical heating. Thus, microwave heating produced lesser variations in drug release. The optimized gel matrices demonstrated that the observed percentage of drug release, CV, and MDT were within the prediction interval generated by DX®. The release mechanism of the matrix formulations followed the Peppas-Korsmeyer anomalous transport model.

    Conclusion: The DoE-supported microwave-assisted approach could be applied to optimize the critical factors of drug release with less variation.

    Matched MeSH terms: Heating
  17. Pati S, Jena P, Shahimi S, Nelson BR, Acharya D, Dash BP, et al.
    Data Brief, 2020 Oct;32:106081.
    PMID: 32775581 DOI: 10.1016/j.dib.2020.106081
    This dataset presents morphological features, elemental composition and functional groups of different pre- and post-gamma (γ)-irradiated chitosan (10kGy & 20kGy) prepared from shrimp waste. The γ-irradiated chitosan was characterized using Fourier transfer infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analyses. Thermogravimetry/differential thermal analysis (TG/DTA) were performed using Perkin Elmer Pyris Diamond DSC with a heating rate of 10 °C/minute and dynamic synthetic atmospheric air set at flow rate of 100 ml/minute. We observed γ-irradiated chitosan to have shorter polymer size, small pores and compacted structure with active alkyl and hydroxyl groups when compared to non-irradiated chitosan. Our data provides baseline understanding for structure of shrimp chitosan after 60Co exposure which means, the biopolymer becomes more stable and is considered suitable for vast food industry applications.
    Matched MeSH terms: Heating
  18. Fatima N, Karimov KS, Qasuria TA, Ibrahim MA
    J Alloys Compd, 2020 Dec 30;849:156702.
    PMID: 32834521 DOI: 10.1016/j.jallcom.2020.156702
    In this research, due to the present pandemic of COVID-19, we are proposing a stable and fixed semitransparent photo-thermoelectric cell (PTEC) module for green energy harvesting. This module is based on the alloy of Bismuth Telluride Selenide (Bi2Te3Se), designed in a press tablet form and characterized under solar energy. Here, both aspects of solar energy i.e., light and heat are utilized for both energy production and water heating. The semitransparent PTEC converts heat energy directly to electrical energy due to the gradient of temperature between two electrodes (top and bottom) of thermoelectric cells. The PTEC is 25% transparent, which can be varied according to the necessity of the utilizer. The X-ray diffraction of material and electric characterization of module i.e., open-circuited voltage (VOC) and Seebeck coefficient were performed. The experimental observations disclose that in the proposed PTEC module with an increment in the average temperature (TAvg) from 34 to 60 °C, results in the rise of VOC ∼ 2.4 times. However, by modifying the size of heat-absorbing top electrode and by increasing the temperature gradient through the addition of water coolant under the bottom electrode, an uplift in the champion device results in as increment of VOC ∼5.5 times and Seebeck coefficient obtained was -250 μV/0C, respectively. Results show that not only the selection of material but also the external modifications in the device highly effective the power efficiency of the devices. The proposed modules can generate electric power from light and utilize the penetrating sunlight inside the room and for the heating of the water which also acts as a coolant. These semitransparent thermoelectric cells can be built-in within windows and roofs of buildings and can potentially contribute to green energy harvesting, in situations where movement is restricted locally or globally.
    Matched MeSH terms: Heating
  19. Elgadir MA, Bakar J, Zaidul ISM, Rahman RA, Abbas KA, Hashim DM, et al.
    Compr Rev Food Sci Food Saf, 2009 Jul;8(3):195-201.
    PMID: 33467796 DOI: 10.1111/j.1541-4337.2009.00078.x
      This review article highlights the thermal behaviors of selected starches that were studied using differential scanning calorimetery (DSC) with data shown in various research publications. The starches of sago, potato, sweet potato, cassava, yam, and corn are included in this overview. Our examinations indicate that thermal properties are highly affected by the type of starch, its amylose/amylopectin content, and the presence of other food ingredients such as sugar, sodium chloride, water, milk, hydrocolloids, and meat. When the heating temperatures of the starches were increased, the DSC measurements also showed an increase in the temperatures of the gelatinization (onset [To ], peak [Tp ], and conclusion [Tc ]). This may be attributed to the differences in the degree of crystallinity of the starch, which provides structural stability and makes the granule more resistant to gelatinization.
    Matched MeSH terms: Heating
  20. Pham TV, Nguyen TT, Nguyen DT, Thuan TV, Bui PQT, Viet VND, et al.
    J Nanosci Nanotechnol, 2019 02 01;19(2):1122-1125.
    PMID: 30360214 DOI: 10.1166/jnn.2019.15926
    Recently, the graphite based materials have gained interest as excellent platforms to remove aqueous pollutants via adsorption routes. This is given that such materials possess large specific surface area and low density. In the present work, a comparative study of two facile and effective approaches is conventional thermal heating and microwave irradiation methods to fabricate expanded graphite from available flake graphite sources of Vietnam for oil-contaminated water purification. The as-prepared expanded graphite was characterized by using FT-IR, SEM, XRD and BET analysis. The results exhibited that expanded graphite has multilevel pore structures and the surface area of expanded graphite obtained from microwave irradiation and conventional heating was 147.5 (m²/g) and 100.97 (m²/g) under optimal processing conditions. The as-synthesized expanded graphite from the microwave irradiation method was found to have higher adsorption capacities for diesel oil, crude oil, and fuel oil compared to conventional heating method.
    Matched MeSH terms: Heating
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