Search results for "PULP"

In vitro evaluation of the ability of three apex locators to determine the working length during retreatment.

2005

The purpose of this in vitro study was to evaluate the accuracy of three apex locators in determining the working length during the retreatment process. Twenty extracted single-rooted human teeth with mature apices were used in this study. The root canal length of each tooth was measured placing a #15 file until the tip was visible at the apical foramen. The direct visual measurement was reduced by 0.5 mm and recorded. The root canals were instrumented and filled to the direct visual measurement using lateral compaction technique. After 7 days the teeth were retreated using three apex locators: ProPex, NovApex, and Root ZX, for determining the retreatment working length. Afterward, comparis…

Oval fiber posts do not improve adaptation to oval-shaped canal walls.

2011

Abstract Introduction Oval fiber posts attempt to provide better adaptation to root canals. The hypothesis of this study was that there are no differences in adaptation of oval and circular fiber posts to canal walls. Methods Posts were inserted in 20 canals; 10 were oval, and 10 were circular. The posts were cemented with composite cement. Coronal, middle, and apical sections were observed through a microscope. The space occupied by the post and the maximum distance between it and the canal wall were calculated. The 2 groups were compared with analysis of variance. In all the analyses the level of significance was set at P Results The proportion of space occupied by the post showed no sign…

Higher oxidative stress in human dental pulp stem cells cultured at 21% O2 compared to 5% O2

2012

Valorization of Wastewater from Table Olives: NMR Identification of Antioxidant Phenolic Fraction and Microwave Single-Phase Reaction of Sugary Fract…

2021

The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phen…

Effect of high levels of CO 2 on the electrochemical behavior and the enzymatic and non‐enzymatic antioxidant systems in black and white table grapes…

2019

[Bakghround]: In this study, we analyzed the effect of the application of high levels of CO2 (20 kPa CO2  + 20 kPa O2  + 60 kPa N2 ) for 3 days at low temperature on a white table-grape cultivar (Superior Seedless) in comparison with a black one (cv. Autumn Royal) in terms of quality parameters. We also used a solid-state voltammetry methodology to analyze the effect of the 3-day gaseous treatment in berry tissues from both cultivars in the first stage of storage. We determined the role of the non-enzymatic (total phenols, total anthocyanins, and antioxidant activity) and the enzymatic antioxidant (catalase (GCAT), ascorbate peroxidase (VcAPX) gene expression) systems in the behaviors of bo…

Biothiols, taurine, and lipid-soluble antioxidants in the edible pulp of Sicilian cactus pear (Opuntia ficus-indica) fruits and changes of bioactive …

2005

Biothiols, taurine, and flavonols, as well as tocopherols and carotenoids have been assessed in the edible pulp of Sicilian red (Sanguigna), yellow (Surfarina), and white (Muscaredda) cultivars of cactus pear. The yellow cultivar has the highest level of reduced glutathione (GSH, 8.1 +/- 0.78 mg/100 g pulp), whereas the white cultivar showed the highest amount of cysteine (1.21 +/- 0.12 mg/100 g pulp). Taurine accounted for 11.7 +/- 1.0 mg/100 g in the yellow pulp, while lower levels were measured in the others. With the exception of kaempferol in the yellow cultivar (2.7 +/- 0.2 microg/100 g pulp), the edible pulp of cactus pear was not a source of flavonols. Very low amounts of lipid-solu…

Photocatalytic ozonation for a sustainable aquaculture: A long-term test in a seawater aquarium

2019

Abstract A long-term test at a laboratory scale with a closed system (a coral reef aquarium) has been carried out to study the potentialities of photocatalytic ozonation and photocatalysis for the removal of noxious organic compounds in recirculating systems (aquaria and recirculating aquaculture systems) working with a minimum make up of new water. Attention has been focused not only on the depuration capabilities but also on possible negative phenomena, some of which could become apparent only at long times. After having tuned the system by setting appropriate operating conditions and procedures, positive results were obtained. In particular, it was observed that the alternation of photoc…

The possibilities of using the aspen poplar seeds (Populus tremula L.) for the purpose of removing monoaromatic hydrocarbons from an aqueous solution

2018

Sorption of oil-related products (including mainly the propellants) is the very basic process that counteracts spreading these types of pollution into environment. Plenty of synthetic substances are used as sorbents for binding organic compounds (including the monoaromatic hydrocarbons) both from the surface and underground waters. The aim of this paper is to present results of the research on the possibilities of using the aspen poplar (Populus tremula L.) seeds as a sorbent of monoaromatic hydrocarbons from an aqueous solution. In order to increase sorption capacity, the seeds biomass was submitted for the process of mercerizing in diversified time and temperature in water and the NaOH so…

Biosorption lead(II) and nikel(II) from an aqueous solution by bacterial biomass

2010

Biosorption lead(II) and nikel(II) from an aqueous solution by bacterial biomass The optimum conditions for biosorption of Pb(II) and Ni(II) from aqueous solution were investigated, by using living and nonliving Pseudomonas fluorescens and Bacillus pumilus isolated from wastewater treatment plant. It was found that the optimum pH for Pb(II) removal by living and nonliving cells was 6.0, while 7.0 for Ni(II) removal. At the optimal conditions, metal ion biosorption was increased as the initial metal concentration increased. The binding capacity by living cells is significantly higher than that of nonliving cells at tested conditions. The maximum biosorption capacities for lead and nickel by …

Description of kraft cooking and oxygen–alkali delignification of bamboo by pulp and dissolving material analysis

2008

Abstract The oxygen delignification of two bamboo ( Bambusa procera ) kraft pulps with kappa numbers of 13.6 and 20.0 were studied under typical conditions. Based on detailed analysis data on both the kraft and oxygen-delignified pulps and the corresponding spent liquors (black liquors and oxygen stage effluents), three yield and four selectivity estimation methods, utilizing component material balances, were tested resulting in the value ranges 96.2–97.9% and 43.5–60.4%, respectively, for oxygen delignification process studied. The traditional selectivity using the viscosity and kappa number relation was 66.9–68.4%. The studied bamboo kraft pulps behaved typically as birch kraft pulps duri…