• Restorative Dentistry and Endodontics
• /
• v.47 no.2
• /
• pp.17.1-17.8
• /
• 2022

Endodontic microsurgery is a predictable treatment option when orthograde treatment or retreatment is unsuccessful or unfeasible. However, when there is a gross compromise of periapical bone, achievement of bone regeneration after the surgical procedure may be hampered. In such cases, the application of guided tissue regeneration principles, with adjunctive use of leukocyte platelet-rich fibrin to fill the bone defect as a bone substitute and as a membrane to cover the site, provides a cost-effective solution with the benefits of accelerated physiological healing and reduced post-surgical pain and discomfort. This case report presents 2 cases of endodontic microsurgery of the upper lateral incisors with loss of buccal cortical plate, where platelet-rich fibrin was successfully applied.

• Polymer(Korea)
• /
• v.31 no.4
• /
• pp.356-367
• /
• 2007

Three kinds of amylose derivatives such as: cholesteryloxycarbonated amyloses(CAMs) with degree of esterification(DE) ranging from 1.8 to 3, (6-cholesteryloxycarbonyl)pentanoated amyloses(PAMs) with DE ranging from 0.3 to 3, and fully cholesteryloxycarbonated PAMs(CPAMs) were synthesized, and their thermotropic liquid crystalline properties were investigated. CAMs with $DE{\geq}2.6$, PAM with DE=1.6 and all the CPAMs formed enantiotropic cholesteric phases, whereas PAM with $DE{\geq}2.2$ exhibited monotropic cholesteric phases. PAM with $DE{\geq}2.2$ and CPAMs with (6-cholesteryloxycarbonyl)pentanoyl DE (DS) more than 1.0 formed cholesteric phases with left-handed helical structures whose optical pitches (${\lambda}_{m'}s$) decrease with increasing temperature. However, the ${\lambda}_{m'}s$ of these samples decreased with increasing DS at the same temperature. On the other hand, CAMs, PAM with DE=1.6, and CPAM with DS=0.3 did not display reflection colors over the full cholesteric range, suggesting that the helicoidal twisting power of the cholesteryl group highly depends on the length of the spacer joining the cholesteryl group to the main chain and DS. The thermal stability and degree of order in the mesophase observed for the amylose derivatives highly depended on DE or DS. The results were discussed in terms of the difference ul the hydrogen bond, the internal plasticization, and the decoupling of the motion of side group with the main chain.

• Advances in materials Research
• /
• v.12 no.2
• /
• pp.161-177
• /
• 2023

This paper proposes an analytical method to investigate the free vibration behaviour of new functionally graded (FG) carbon nanotubes reinforced composite beams based on a higher-order shear deformation theory. Cosine functions represent the material gradation and material properties via the thickness. The kinematic relations of the beam are proposed according to trigonometric functions. The equilibrium equations are obtained using the virtual work principle and solved using Navier's method. A comparative evaluation of results against predictions from literature demonstrates the accuracy of the proposed analytical model. Moreover, a detailed parametric analysis checks for the sensitivity of the vibration response of FG nanobeams to nonlocal length scale, strain gradient microstructure-scale, material distribution and geometry.

• The Korean Journal of Ceramics
• /
• v.6 no.3
• /
• pp.280-285
• /
• 2000

The electrolyte, $(HO)_2C_6H_2(SO_3Na)_2H_2O $(Tiron), disperses efficiently alumina powder in aqueous media and stable suspensions with 60 vol% solid loading can be prepared. The strong adsorption of this additive is mainly due to the ability of the molecule to form chelate rings with the particle surface but electrostatic interactions between the surface charge and the anionic dispersant strongly influence the amount of Tiron adsorbed. By using a cationic exchange route to substitute the counter ion which neutralizes the sulfonate groups, new molecules of dispersant have been prepared, either with mineral cations as $Li^+,\; Na+^,\; NH_4^\;+$, or with organic cations as counter ion but organic counter ions lead to less to less viscous suspensions than $Na^+$ in particular when the number of carbon atoms of the aliphatic chain increases from 1 to 3.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.9
• /
• pp.1296-1302
• /
• 2004

This study was conducted to evaluate the possible application of 2 D-SDS-PAGE (2 DE)-based proteome analysis techniques to the assessment of extreme proteolysis in postmortem skeletal muscle. Eight Hanwoo longissimus muscles were incubated immediately after slaughter for 24 h at 5$^{\circ}C$, 15$^{\circ}C$ or 36$^{\circ}C$. Warner Bratzler (WB)-shear force and ultrastructural configuration were determined at 24 h, and rate of proteolysis to 24 h was determined by 1 D-SDS-PAGE (1 DE) and 2 DE. In addition, tentative protein identification was performed from peptide mass fingerprints of MALDI-ToF analysis of major protein groups on 2 DE profiles. The result showed that although ultrastructural configuration was similar between the 5$^{\circ}C$ and 36$^{\circ}C$ treatments, meat at 5$^{\circ}C$ had higher WBshear force (approximately 5 kg greater). A higher rate of protein degradation at 36$^{\circ}C$ was observed based on Troponin-T degradation, 1 DE, and 2 DE analysis. This indicates that proteolysis during the early postmortem period was a significant determinant of shear force at 24 h. Little difference in proteolysis between 5$^{\circ}C$ and 15$^{\circ}C$ treatments was found based on classic 1 DE profile assessment. Meanwhile, considerable differences in the 2 DE profiles between the two treatments were revealed, with substantially higher rate of proteolysis at 15$^{\circ}C$ compared to 5$^{\circ}C$. Nuclease treatment improved 2 DE profile resolution. 400 ${\mu}$g and 600 ${\mu}$g of sample loading appeared to be appropriate for 24 cm pH 3-10 and pH 5-7 IPG strips, respectively. Protein detection and quantification of the 5$^{\circ}C$, 15$^{\circ}C$ and 36$^{\circ}C$ 2 DE profiles revealed 78, 163 and 232 protein spots respectively that were differentially modified in terms of their electrophoretic properties between approximately pI 5.3-7.7 with the molecular weight range of approximately 71-12 kDa. The current results demonstrated that 2 DE was a superior tool to 1 DE for characterising proteolysis in postmortem skeletal muscle.

• Microbiology and Biotechnology Letters
• /
• v.48 no.2
• /
• pp.193-204
• /
• 2020

Sixteen acetic acid bacteria (AAB) were isolated from blueberries and citric fruits of the Salto Grande region (Concordia, Entre Rios, Argentina) using enrichment techniques and plate isolation. Enrichment broths containing ethanol and acetic acid enabled maximum AAB recovery, since these components promote their growth. Biochemical tests allowed classification of the bacteria at genus level. PCR-RFLP of the 16S rRNA and PCR-RFLP of the 16S-23S rRNA intergenic spacer allowed further classification at the species level; this required treatment of the amplified products of 16S and 16S-23S ITS ribosomal genes with the following restriction enzymes: AluI, RsaI, HaeIII, MspI, TaqI, CfoI, and Tru9I. C7, C8, A80, A160, and A180 isolates were identified as Gluconobacter frateurii; C1, C2, C3, C4, C5, C6, A70, and A210 isolates as Acetobacter pasteurianus; A50 and A140 isolates as Acetobacter tropicalis; and C9 isolate as Acetobacter syzygii. The bacteria identified by 16S rRNA PCR-RFLP were validated by 16S-23S PCR-RFLP; however, the C1 isolate showed different restriction patterns during identification and validation. Partial sequencing of the 16S gene resolved the discrepancy.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.2
• /
• pp.234-241
• /
• 2017

Potato peels (PP) contain several bioactive compounds. These compounds are known to provide human health benefits, including antioxidant and antimicrobial properties. In addition, these compounds could have effects on human enteric viruses that have not yet been reported. The objective of the present study was to evaluate the phenolic composition, antioxidant properties in the acidified ethanol extract (AEE) and water extract of PP, and the antiviral effects on the inhibition of Av-05 and MS2 bacteriophages, which were used as human enteric viral surrogates. The AEE showed the highest phenolic content and antioxidant activity. Chlorogenic and caffeic acids were the major phenolic acids. In vitro analysis indicated that PP had a strong antioxidant activity. A 3 h incubation with AEE at a concentration of 5 mg/ml was needed to reduce the PFU/ml (plaque-forming unit per unit volume) of Av-05 and MS2 by 2.8 and $3.9log_{10}$, respectively, in a dose-dependent manner. Our data suggest that PP has potential to be a source of natural antioxidants against enteric viruses.

• Kyungpook Mathematical Journal
• /
• v.13 no.2
• /
• pp.275-280
• /
• 1973

• Journal of Preventive Medicine and Public Health
• /
• v.53 no.4
• /
• pp.211-219
• /
• 2020

Objectives: The goal of this study was to identify chronic conditions and multimorbidity patterns in patients with coronavirus disease 2019 (COVID-19) and to examine their associations with pneumonia and death. Methods: This cross-sectional study analyzed the official data of COVID-19 patients in Mexico through May 18, 2020 (released by the Secretaría de Salud de México). Adjusted logistic regression models were applied to assess the associations of comorbidities with pneumonia and death. The marginal effects were estimated, and the probability of pneumonia or death according to the number of comorbidities was graphed for each year of age. Results: Of the 51 053 COVID-19 patients enrolled in the final analysis, 27 667 (54.2%) had no chronic conditions, while 13 652 (26.7%), 6518 (12.8%) and 3216 (6.3%) were reported to have 1, 2, and 3 or more simultaneous conditions, respectively. Overall, a significant incremental gradient was observed for the association between multimorbidity and pneumonia (p<0.001); for 2 chronic conditions, the adjusted odds ratio (aOR) was 2.07 (95% confidence interval [CI], 1.95 to 2.20), and for ≥3 conditions, the aOR was 2.40 (95% CI, 2.22 to 2.60). A significant incremental gradient was also found for the relationship between multimorbidity and death (p<0.001); an aOR of 2.51 (95% CI, 2.30 to 2.73) was found for 2 chronic conditions and an aOR of 3.49 (95% CI, 3.15 to 3.86) for ≥3 conditions. Conclusions: Underlying chronic conditions and multimorbidity are associated with pneumonia and death in Mexican COVID-19 patients. Future investigation is necessary to clarify the pathophysiological processes behind this association, given the high burden of chronic diseases in various countries, including Mexico.

• Corrosion Science and Technology
• /
• v.16 no.2
• /
• pp.59-63
• /
• 2017

Chelating solutions can be damaged by strong acids during oil production. To design effective corrosion inhibitors and other alternatives for corrosion control, it is important to understand not only the behavior of the system under operating condition but also the kinetics of electrochemical reactions during the corrosion process. In this study, the electrochemical behaviors of P-110 steel in aqueous fluids based on ethylenediaminetetraacetic acid (EDTA) compounds under various temperatures and hydrodynamic regime conditions were assessed. Electrochemical measurements were conducted using rotating disc electrodes manufactured. Electrolytes were prepared using aqueous compounds of EDTA like diammonium salt, disodium salt, and tetrasodium salt. Potentiodynamic polarization, electrochemical impedance, and mass loss tests were performed in order to assess the corrosion kinetic in electrolytes. Hydrodynamic effects were observed only in the cathodic polarization curve. This proves that hydrodynamic regime plays an important role in the corrosion of steel mainly in disodium and diammonium EDTA solutions. Two cathodic reactions controlled the corrosion process. However, oxygen level and pH of the electrolyte played the most important role in metal corrosion. Corrosion rates in those fluids were decreased drastically when oxygen concentration was reduced.