The addition of Superabsorbent Polymer (SAP) decreases the effect of autogenous shrinkage present in pastes, mortars, and concretes. In this study we investigated the influence of the addition of SAP ...in self-compacting cement paste mixtures. Eighteen 5 × 10 cylindrical specimens were molded in all, three for each mixture (CPII base, CPII 0.15%SAP/600μm, CPII 0.15%SAP/800 μm, CPV base, CPV 0.15%SAP/600 μm, CPV 0.15%SAP/800 μm). Two types of cement were tested, CP II-Z and CP V-ARI with 0.15% of weight replaced per two diameters of SAP (600 μm and 800 μm). The samples followed the standards required. Mini slump tests were carried out in the fresh state, and uniaxial compressive strength, elastic modulus, specific mass, absorption, and air content in the hardened state after 28 days. The results obtained show the SAP is high indicated to replaced cement in small % of weight i/to fresh and hardened paste. Likewise, the group mix n° 3 composed of CPII 0.15% of SAP with 800 μm diameter presented the best result.
Abstract The ageing time of a starch gel can influence the structure of hydrogels as the reorganization of amylose–amylopectin can progressively change over time. This study evaluates the influence ...of ageing time prior to freeze–thaw cycles on pore formation, water absorption, and mechanical resistance of pinhão starch hydrogels. The hydrogels are prepared by starch gelatinization followed by ageing for 0, 3, 6, and 9 h before the freeze–thaw cycles. Immediately frozen gel (0 h) produces a hydrogel with a honeycomb structure with regular pores size while ageing (3, 6, and 9 h) created a spongy structure. The hydrogels aged for 0 and 3 h fragment after the compression test, while those aged for 6 and 9 h maintain firm and intact structures. The 0 h aged hydrogels have the lowest water absorption (520%) and the highest mechanical resistance (1407.50 g). The hydrogels aged for 3, 6, and 9 h show water absorption between 670% and 700% and mechanical resistance of 635.34–800.79 g. In conclusion, a minimum of 6 h gel ageing before freeze–thaw cycles is necessary to achieve a firm structure and ensure the required functional properties for practical application with pinhão starch.
Meat products are classified as perishable foods and have favourable conditions for the multiplication of microorganisms such as Listeria monocytogenes, an important pathogen associated with ...ready-to-eat foods. Natural compounds are used for food preservation combined with encapsulation techniques to improve efficiency. This study evaluated the anti-Listeria potential of isolated and combined microencapsulated oregano (OEO) and cinnamon (CEO) essential oils in Italian salami. Different combination ratios of OEO and CEO were tested and 50:50 ratio (OEO:CEO) was encapsulated using sodium alginate. The microcapsules were evaluated for encapsulation efficiency (EE), morphology and action against L. monocytogenes in a meat matrix. Empty microcapsules and 50/50 combined EO were incorporated into the Italian salami to evaluate the physicochemical, microbiological and sensory properties. All combinations of EO showed L. monocytogenes inhibition zone and CIM with 1:16 dilution. The microencapsulated EO had 98.36% encapsulation efficiency. Using 2% microcapsule had a significant reduction of L. monocytogenes from the control. Even though the panellists mentioned the sandy attribute in the CATA, the salami with EO microcapsules texture did not differ from the control. Although the essential oils had high encapsulation efficiency, the smell and flavour of cinnamon and oregano interfered negatively with the sensory analysis. However, the encapsulation of the combined essential oils (50/50) significantly reduced L. monocytogenes in Italian salami.
•Oregano and cinnamon essential oil (EOs) had great anti-Listeria action.•A combination of 50/50 EOs was encapsulated with 98% encapsulation efficiency.•Capsule (3%) had reduced L. monocytogenes counts in the meat matrix (about 80% inhibition).•EOs flavor and aroma, even encapsulated, were a challenge for salami application.•Salami was mentioned as bitter, spicy, acid odor, dry texture, odor and essence flavor.
The aim of the present study was to investigate the effects of PDT using the photosensitizer 5-aminoulevulinic acid (5-ALA) in oral squamous cell carcinoma (OSCC) behavior, mainly regarding its role ...on the cancer stem cell (CSC) phenotypes and in maintenance of the stem cell properties. Two OSCC cell lines were used and divided in the groups: Control, 5-ALA, LED 6 J/cm
and PDT. MTT and Neutral red assays were used to access cellular viability, cell migration was evaluated by the wound healing assay. The stem cell phenotype was analyzed by flow cytometry to evaluate the CD44
/ESA
, CD44
/ESA
and CD44
populations, by the clonogenic and tumor sphere formation assays as well as by RT-qPCR. The presence of Protoporphyrin IX in each CSC fraction was evaluated by flow cytometry. The OSCC cell lines showed a significant decrease in cell viability and migration after PDT. The percentage of CD44
/ESA
cells decreased after PDT, which was associated with an increase in the CD44
cells and with a functional decrease in the colony and sphere formation capacity. CD44
/ESA
cells showed increased PpIX, which contributed for their greater sensitivity to PDT. INV gene increased significantly after PDT, indicating cellular differentiation. Altogether, our results demonstrate that 5-ALA mediated PDT decreases not only the fraction of oral CSC but also their functional capabilities, inducing their differentiation.
Photosynthetic microorganisms have been widely studied as an alternative technology for CO2 capture. Aiming to overcome some operational challenges in the application of these microorganisms for gas ...treatment on a large scale, the immobilization of microalgae in solid matrices emerges as an alternative to facilitate effective management of microalgae culture during harvesting process. In this work, different matrices for microalgae immobilization composed of silica/alginate were obtained varying silica precursors. The synthesized materials were characterized in terms of their specific surface area, cell viability, transparency and physical-chemical properties. Additionally, a new methodology was developed to evaluate the CO2 capture by microalgae using a pressurized system with natural gas mixture. Tests were carried out exploring the influence of some variables, such as headspace volume, cell concentration, stirring and pressure. Once the optimized parameters were established, the amount of CO2 captured by immobilized microalgae was investigated for 7 days by determining the CO2 relative concentrations using gas chromatography. The results of immobilized microalgae showed levels of CO2 removal of 41.4%. This work proved the potential application of the studied biomaterial for natural gas processing, making even more feasible the adoption of this technology for selective capture of CO2 on an industrial scale.
Abstract The aim of this work was to investigate the phenolic content and antioxidant capacity of infusions of commercial herb samples (fennel, anise, peppermint, lemon grass and lemon balm) ...popularly consumed in Brazil. The infusion preparation for phenolic extraction was optimized using multivariate planning. Spectrophotometric methods were used to determine in vitro antioxidant activity and total phenolic and flavonoid content. Peppermint infusions had higher phenolic content and antioxidant potential. It was developed and validated a method by HPLC-DAD for the determination of caffeine, phenolic acids and flavonoids and applied for the analysis of the composition of the infusions. Higher concentrations were obtained for chlorogenic and p-coumaric phenolic acids and for flavonoids rutin and catechin. Principal Components Analysis and Hierarchical Cluster Analysis were applied for the comparative evaluation of the phenolic composition of the infusions. The multivariate analyzes indicate that the phenolic profile for the samples of the same species tend to present greater similarities in relation to other herbs and one of the analyzed samples, commercialized as anise, does not belong to the P. anisum species.
Non-alcoholic steatohepatitis (NASH) is characterized by steatosis, lobular inflammation, and enlargement of the diameter of hepatocytes (ballooning hepatocytes), with or without fibrosis. It affects ...20% of patients with non-alcoholic fatty liver disease (NAFLD). Due to liver dysfunction and the numerous metabolic changes that commonly accompany the condition (obesity, insulin resistance, type 2 diabetes, and metabolic syndrome), the secretion of organokines is modified, which may contribute to the pathogenesis or progression of the disease. In this sense, this study aimed to perform a review of the role of organokines in NASH. Thus, by combining descriptors such as NASH, organokines, oxidative stress, inflammation, insulin resistance, and dyslipidemia, a search was carried out in the EMBASE, MEDLINE-PubMed, and Cochrane databases of articles published in the last ten years. Insulin resistance, inflammation and mitochondrial dysfunction, fructose, and intestinal microbiota were factors identified as participating in the genesis and progression of NASH. Changes in the pattern of organokines secretion (adipokines, myokines, hepatokines, and osteokines) directly or indirectly contribute to aggravating the condition or compromise homeostasis. Thus, further studies involving skeletal muscle, adipose, bone, and liver tissue as endocrine organs are essential to better understand the modulation of organokines involved in the pathogenesis of NASH to advance in the treatment of this disease.
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