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1.
Didah Nur Faridah Sanaz Damaiyanti Dias Indrasti Anuraga Jayanegara Frendy Ahmad Afandi 《International Journal of Food Science & Technology》2022,57(4):1965-1974
Resistant starch (RS) can be generated through heat moisture treatment (HMT). The HMT was conducted by modifying starch using different ratio of moisture content, high temperature and heating time. A number of studies showed that the effects of HMT on RS contents in cereals, pulses, tubers and fruits were inconsistent. This study aimed to analyse the impact of HMT on RS level in various carbohydrate sources through a meta-analysis approach. Study selection was conducted with the PRISMA method. There were 21 relevant studies and 67 data used for meta-analysis. The database was analysed by using Hedges’ d. The results showed that there was a significant impact of HMT on RS level of cereals, especially wheat. The highest increase in RS levels for various carbohydrate sources in starch was influenced by the interaction of treatment between water content at 15 ≤ x < 25%, heating time at 0.25 < x ≤ 6 h and temperature at 120 ≤ x ≤ 130 °C. 相似文献
2.
Guilherme M. Martins Cristiano Fantini Roberto L. Moreira Anderson Dias 《Ceramics International》2021,47(11):15202-15209
In this work, Gd2Ge2O7 polymorphs were obtained by solid-state reactions at 1100–1300 °C. Structural and vibrational features were investigated by X-ray diffraction and Raman spectroscopy. For the triclinic (space group P1) polymorph, all the predicted phonons were discerned in perfect agreement with the group theory calculations, while for the tetragonal polymorph (space group P41212), 53 bands of the 81 predicted modes could be identified and characterized. The Gd3+ 4f-4f electronic transitions were investigated by diffuse reflectance spectroscopy in the range 200–340 nm. By applying the Kubelka-Munk function, it was possible to determine the bandgap values for all ceramics studied. The tetragonal polymorph exhibited higher bandgap values (5.88 eV) than the triclinic one (5.59 eV), which are both more energetic than other pyrochlore polymorphs reported in the literature. The results indicate that the presence of polymorphism in Gd2Ge2O7 ceramics can be used to produce tailor-made materials since their crystal structures have a strong influence on their optical properties. Consequently, these properties could be used to tuning the optical properties of Gd-containing materials to sensitize and transfer energy to other luminescent lanthanide ions, aiming for innovative applications. 相似文献
3.
da Silva Edson Santos de Mello Prado Renato Soares Anelisa de Aquino Vidal Lacerda de Almeida Hilario Junior dos Santos Durvalina Maria M. 《SILICON》2021,13(3):813-818
Silicon - Corn plants are highly demanding of nitrogen and the application of silicon has been studied because it minimizes stress from different natures, and for the better utilization of some... 相似文献
4.
Camila C. Lopes Wagner A. Pinheiro Daniel Navarro da Rocha José G. Neves Américo Bortolazzo Correr José R.M. Ferreira Rafael M. Barbosa Jefferson R.F. Soares Jheison L. Santos Marcelo H. Prado da Silva 《Ceramics International》2021,47(6):7653-7665
The repair of bone fractures is a clinical challenge for patients with impaired healing, such as osteoporosis. Currently, different strategies have been developed to design new biomaterials, enhancing their interactions with biological systems and conducting the cellular behavior in the desired direction to help fracture healing. In the present work, hydroxyapatite-graphene oxide (HA-GO) nanocomposites were produced and the morphological and physicochemical influences of the addition of 0.5 wt%, 1.0 wt% and 1.5 wt% of GO to HA were observed. FEG-SEM and TEM analyses of HA-GO nanocomposites showed HA nanoparticles adhered to the surface of the GO sheets, suggesting an effective method to form nanostructured graphene-based biomaterials. As confirmation, physicochemical analyses by Raman, FTIR and TGA demonstrated a strong affinity between HA and GO, according to the increase of concentration from 0.5 wt% to 1.5 wt% GO in the HA-GO nanocomposites. Also, in order to evaluate the HA-GO nanocomposites behavior under biological microenvironment, in vitro bioactivity and indirect cytotoxicity tests were performed. FEG-SEM analyses confirmed the positive results for the bioactivity properties of HA-GO nanocomposite and indirect cytotoxicity demonstrated that even with a decrease in the hDPSCs viability and proliferation, when increasing to 1.5 wt% of GO concentration, high level of cell viability was exhibited by HA-GO nanocomposites. These biological results suggested the 0.5 wt% HA-GO nanocomposite as a potential bioactive bone graft and a promising biomaterial for bone tissue regeneration, when compared to the pure HA. 相似文献
5.
P. Carrasqueira H. Rocha J. M. Dias T. Ventura B. C. Ferreira M. C. Lopes 《International Transactions in Operational Research》2023,30(1):206-223
Radiation therapy is a technology-driven cancer treatment modality that has experienced significant advances over the last decades, due to multidisciplinary contributions that include engineering and computing. Recent technological developments allow the use of noncoplanar volumetric modulated arc therapy (VMAT), one of the most recent photon treatment techniques, in clinical practice. In this work, an automated noncoplanar arc trajectory optimization framework designed in two modular phases is presented. First, a noncoplanar beam angle optimization algorithm is used to obtain a set of noncoplanar irradiation directions. Then, anchored in these directions, an optimization strategy is proposed to compute an optimal arc trajectory. The computational experiments considered a pool of twelve difficult head-and-neck tumor cases. It was possible to observe that, for some of these cases, the optimized noncoplanar arc trajectories led to significant treatment planning quality improvements, when compared with coplanar VMAT treatment plans. Although these experiments were done in a research environment treatment planning software (matRad), the conclusions can be of interest for a clinical setting: automated procedures can simplify the current treatment workflow, produce high-quality treatment plans, making better use of human resources and allowing for unbiased comparisons between different treatment techniques. 相似文献
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Comprehensive design schemes and specifications have progressively shaped Master-Planned Communities (MPCs). The market largely predetermines these outcomes, with background input from communities. Therefore, this paper endeavours to define the fundamental structures that generate differences between market actors and residents within the North Lakes MPC. This study employs ‘habitus theory’, which is a sociological phenomenon describing the divergence of personal outlooks and expertise. The application of this theory is thus illustrative of the evolution of distinct observations within MPCs. Contemporary studies have under-researched these inherent gaps between communities, authorities, and critics, and these frictions could be exacerbated within restrictive developmental contexts. Epistemic and objectified content analyses collated over many years and sources will uncover the underlying differences between the relevant groups. These analyses will enable the progression of a framework for understanding power relation biases and how reflexivity can enhance current consultative methods. 相似文献
8.
Juliana Cristina Castro Giseli Cristina Pante Bruno Martins Centenaro Rafaela Takako Ribeiro De Almeida Eduardo Jorge Pilau Benedito Prado Dias Filho 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2020,37(9):1531-1541
ABSTRACT There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this study was to evaluate the antifungal and antimycotoxigenic action of essential oils (EOs) from Zingiber officinale, Cinnamomum zeylanicum and Cymbopogon martinii against Fusarium verticillioides, a spoilage and toxigenic fungus. Essential oils were first chemically characterised by gas chromatography coupled to mass spectrometry, and their antioxidant potential was measured by the DPPH, ABTS and FRAP methods. Minimum inhibitory concentration (MIC) and disc diffusion were used to assess antifungal activity. Scanning electron microscopy was used to evaluate morphological changes in the fungus. Antimycotoxigenic activity of the EOs against the production of fumonisin B1 and B2 by F. verticillioides was evaluated using ultra-high-performance liquid chromatography system. Z. officinale, C. zeylanicum and C. martinii EOs were predominantly composed by zingiberene and geranial; eugenol; and geraniol, respectively. All the EOs had high antioxidant power, especially that from C. zeylanicum. The MICs were 250, 500 and 2,000 µg mL?1 for C. zeylanicum, C. martinii and Z. officinale EOs, respectively. Mycelial reduction of F. verticillioides was observed when EOs were used, and the lowest activity was detected in the Z. officinale EO. Overall, the tested EOs promoted structural damage to the fungal cell wall, decreased conidia size and mycelial reduction. Antimycotoxigenic evaluation of the EOs evidenced a significant reduction (p < .05) in the production of fumonisins B1 and B2 with all the EOs evaluated in the study. These results suggest that especially C. zeylanicum and C. martinii EOs are highly useful for controlling F. verticillioides and fumonisins production. 相似文献
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10.
Polyana Alves Radi Angela Vieira Lucas Manfroi Karina Carvalho de Farias Nass Marco Antonio Ramirez Ramos Priscila Leite Gislene Valdete Martins Jorge Benedito Freire Jofre Lucia Vieira 《Ceramics International》2019,45(7):9686-9693
There has been a recent increase in both the production and consumption of ethanol due to the numerous environmental advantages that it offers, such as the fact that it can be produced from a variety of renewable materials, for instance corn and cellulose, or it can be obtained from sugarcane bagasse and biomass (2nd and 3rd generation ethanol). The result of this is that nowadays ethanol is widely seen as the dominant biofuel – or as a blend component in gasoline or pure fuel - in many countries.However, one disadvantage of the use of ethanol is the high corrosive behavior that occurs when its hygroscopic properties are exposed to a large number of materials. Xiaoyuan Lou and Preet Singh showed that the increase of water concentration in ethanol induces pitting and metal loss. Diamond-Like Carbon (DLC) films may be a solution to this problem due to the fact that they can be deposited inside tubes, offer good protection levels against corrosion, and reduce the friction coefficient and wear.This paper shows the tribocorrosion and corrosion studies of DLC films deposited on stainless steel grade 304 (SS304) substrates in order to gauge its appropriateness usage in the construction of pipelines and fuel storage tanks. The surface morphology was analyzed before and after 14 days of immersion. The tribocorrosion, friction coefficient, and wear rate were studied in ethanol to see the effects of water concentration. The films showed good adherence to the substrates. Corrosion and tribocorrosion results showed that for bare Stainless Steel 304 the increase of the water content increases the corrosion and the friction coefficient. DLC coated samples presented few points of delamination, and the friction coefficient and open circuit potentials were very low compared with the bare sample which was water concentration independent. 相似文献