La Charreri>a

Torre, Fernando Torres de la,Torres de la Torre, Fernando 한국외국어대학 서반아어과 1986 AULA Vol.4 No.1

Characterization of mandibular molar root and canal morphology using cone beam computed tomography and its variability in Belgian and Chilean population samples

Torres, Andres,Jacobs, Reinhilde,Lambrechts, Paul,Brizuela, Claudia,Cabrera, Carolina,Concha, Guillermo,Pedemonte, Maria Eugenia Korean Academy of Oral and Maxillofacial Radiology 2015 Imaging Science in Dentistry Vol.45 No.2

Purpose: This study used cone-beam computed tomography (CBCT) to characterize mandibular molar root and canal morphology and its variability in Belgian and Chilean population samples. Materials and Methods: We analyzed the CBCT images of 515 mandibular molars (257 from Belgium and 258 from Chile). Molars meeting the inclusion criteria were analyzed to determine (1) the number of roots; (2) the root canal configuration; (3) the presence of a curved canal in the cross-sectional image of the distal root in the mandibular first molar and (4) the presence of a C-shaped canal in the second mandibular molar. A descriptive analysis was performed. The association between national origin and the presence of a curved or C-shaped canal was evaluated using the chi-squared test. Results: The most common configurations in the mesial root of both molars were type V and type III. In the distal root, type I canal configuration was the most common. Curvature in the cross-sectional image was found in 25% of the distal canals of the mandibular first molars in the Belgian population, compared to 11% in the Chilean population. The prevalence of C-shaped canals was 10% or less in both populations. Conclusion: In cases of unclear or complex root and canal morphology in the mandibular molars, CBCT imaging might assist endodontic specialists in making an accurate diagnosis and in treatment planning.

First-principles calculation of volatile organic compound adsorption on carbon nanotubes: Furan as case of study

Torres Ana M.,Correa J. D. 한국탄소학회 2021 Carbon Letters Vol.31 No.5

Sensing of volatile organic compounds (VOCs) is a growing research topic because of the concern about their hazard for the environment and health. Furan is a VOC produced during food processing, and it has been classifed as a risk molecule for human health and a possible biomarker of prostate cancer. The use of carbon nanotubes for VOCs sensing systems design could be a good alternative. In this work, a theoretical evaluation of the interactions between furan and zigzag single-wall carbon nanotubes takes into account diferent positions and orientations of the furan molecule, within a density-functional theory frst-principles approach. The van der Waals interactions are considered using diferent exchange-correlation functionals (BH,C09, DRSLL and KBM). The results indicate that vdW-functionals do not signifcantly afect geometry; however, the binding energy and the distance between furan and nanotube are strongly dependent on the selected exchange-correlation functional. On the other hand, the efects of single and double vacancies on carbon nanotube are considered. It was found that the redistribution of charge around the single-vacancy afects the bandgap, magnetic moment, and binding energy of the complex, while furan interaction with a double-vacancy does not considerably change the electronic structure of the system. Our results suggest that to induce changes in the electronic properties of carbon nanotubes by furan, it is necessary to change the nanotube surface, for example, by means of structural defects.

CO₂ absorption enhancement by nanoabsorbents in Taylor-Couette absorber

Torres Pineda, I.,Kang, Y.T. Pergamon Press ; Elsevier Science Ltd 2016 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.100 No.-

CO<SUB>2</SUB> gas is physically absorbed in liquid methanol in bubbly Taylor-Couette absorber. The experiments are performed in the turbulent regime with rotational Reynolds numbers ranging from 1.9x10<SUP>4</SUP> to 19.2x10<SUP>4</SUP>. The volumetric mass transfer coefficients are obtained for the counter-current operation. Methanol is utilized as the base absorbent. In addition, with the purpose of enhancing CO<SUB>2</SUB> absorption performance, Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles are combined with methanol to produce the absorbent. The results show an increase in the volumetric mass transfer coefficient that reaches a maximum value at 4x10<SUP>4</SUP> rotational Reynolds number for both pure methanol and the nanoabsorbents, after which the absorption rate declines almost linearly with the rotational speed. The reasons for the reduction in the absorption performance are discussed. The maximum enhancement in the volumetric mass transfer coefficient is estimated at 20% for 4x10<SUP>4</SUP> rotational Reynolds number and up to 27% for methanol and Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles at a concentration of 0.1vol%.

Modelling of tension-stiffening in bending RC elements based on equivalent stiffness of the rebar

Torres, Lluis,Barris, Cristina,Kaklauskas, Gintaris,Gribniak, Viktor Techno-Press 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.5

The contribution of tensioned concrete between cracks (tension-stiffening) cannot be ignored when analysing deformation of reinforced concrete elements. The tension-stiffening effect is crucial when it comes to adequately estimating the load-deformation response of steel reinforced concrete and the more recently appeared fibre reinforced polymer (FRP) reinforced concrete. This paper presents a unified methodology for numerical modelling of the tension-stiffening effect in steel as well as FRP reinforced flexural members using the concept of equivalent deformation modulus and the smeared crack approach to obtain a modified stress-strain relation of the reinforcement. A closed-form solution for the equivalent secant modulus of deformation of the tensioned reinforcement is proposed for rectangular sections taking the Eurocode 2 curvature prediction technique as the reference. Using equations based on general principles of structural mechanics, the main influencing parameters are obtained. It is found that the ratio between the equivalent stiffness and the initial stiffness basically depends on the product of the modular ratio and reinforcement ratio ($n{\rho}$), the effective-to-total depth ratio (d/h), and the level of loading. The proposed methodology is adequate for numerical modelling of tension-stiffening for different FRP and steel reinforcement, under both service and ultimate conditions. Comparison of the predicted and experimental data obtained by the authors indicates that the proposed methodology is capable to adequately model the tension-stiffening effect in beams reinforced with FRP or steel bars within wide range of loading.

DOMESTIC INTEGRATION OF RICE MARKETS IN THE PHILIPPINES AND ITS DETERMINANTS

Torres, Maria Angelica C.,Bacud, Eva Salve,Delos Reyes, Julieta 한국무역학회 2019 한국무역학회 국제학술대회 Vol.2019 No.08

Due to the high political significance of rice, government has been putting efforts in order to address rice insufficiency in the Philippines. Provisioning of trade reforms and policies is one of the interventions to improve the availability and affordability of rice in the country, and to protect the welfare of the local rice farmers. Government intervention and support services would not be fully effective if markets are not integrated, since price signals would not be transmitted efficiently and gains from trade will not be fully grasped. This paper examined integration between domestic rice markets across 16 regions in the Philippines using Johansen co-integration approach with 18-year period monthly retail price series of regular-milled rice from January 2000 to December 2017. Determinants of market integration were also identified. It was found out that 63% of the regional rice markets are integrated. Volume of production, distance and shock affected areas have significantly influenced integration among regional rice markets.

How do imaging protocols affect the assessment of root-end fillings?

Torres Fernanda Ferrari Esteves,Jacobs Reinhilde,EzEldeen Mostafa,de Faria-Vasconcelos Karla,Guerreiro-Tanomaru Juliane Maria,dos Santos Bernardo Camargo,Tanomaru-Filho Mário 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.1

Objectives This study investigated the impact of micro-computed tomography (micro-CT)-based voxel size on the analysis of material/dentin interface voids and thickness of different endodontic cements. Materials and Methods Following root-end resection and apical preparation, maxillary premolars were filled with mineral trioxide aggregate (MTA), Biodentine, and intermediate restorative material (IRM) (n = 24). The samples were scanned using micro-CT (SkyScan 1272; Bruker) and the cement/dentin interface and thickness of materials were evaluated at voxel sizes of 5, 10, and 20 µm. Analysis of variance and the Tukey test were conducted, and the degree of agreement between different voxel sizes was evaluated using the Bland and Altman method (p < 0.05). Results All materials showed an increase in thickness from 5 to 10 and 20 µm (p < 0.05). When evaluating the interface voids, materials were similar at 5 µm (p > 0.05), while at 10 and 20 µm Biodentine showed the lowest percentage of voids (p < 0.05). A decrease in the interface voids was observed for MTA and IRM at 20 µm, while Biodentine showed differences among all voxel sizes (p < 0.05). The Bland-Altman plots for comparisons among voxel sizes showed the largest deviations when comparing images between 5 and 20 µm. Conclusions Voxel size had an impact on the micro-CT evaluation of thickness and interface voids of endodontic materials. All cements exhibited an increase in thickness and a decrease in the void percentage as the voxel size increased, especially when evaluating images at 20 µm.

Genetic evaluation of sheep for resistance to gastrointestinal nematodes and body size including genomic information

Torres Tatiana Saraiva,Sena Luciano Silva,Santos Gleyson Vieira dos,Figueiredo Filho Luiz Antonio Silva,Barbosa Bruna Lima,Júnior Antônio de Sousa,Britto Fábio Barros,Sarmento José Lindenberg Rocha 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.4

Objective: The genetic evaluation of Santa Inês sheep was performed for resistance to gastrointestinal nematode infection (RGNI) and body size using different relationship matrices to assess the efficiency of including genomic information in the analyses. Methods: There were 1,637 animals in the pedigree and 500, 980, and 980 records of RGNI, thoracic depth (TD), and rump height (RH), respectively. The genomic data consisted of 42,748 SNPs and 388 samples genotyped with the OvineSNP50 BeadChip. The (co)variance components were estimated in single- and multi-trait analyses using the numerator relationship matrix (A) and the hybrid matrix H, which blends A with the genomic relationship matrix (G). The BLUP and single-step genomic BLUP methods were used. The accuracies of estimated breeding values and Spearman rank correlation were also used to assess the feasibility of incorporating genomic information in the analyses. Results: The heritability estimates ranged from 0.11±0.07, for TD (in single-trait analysis using the A matrix), to 0.38±0.08, for RH (using the H matrix in multi-trait analysis). The estimates of genetic correlation ranged from –0.65±0.31 to 0.59±0.19, using A, and from –0.42±0.30 to 0.57±0.16 using H. The gains in accuracy of estimated breeding values ranged from 2.22% to 75.00% with the inclusion of genomic information in the analyses. Conclusion: The inclusion of genomic information will benefit the direct selection for the traits in this study, especially RGNI and TD. More information is necessary to improve the understanding on the genetic relationship between resistance to nematode infection and body size in Santa Inês sheep. The genetic evaluation for the evaluated traits was more efficient when genomic information was included in the analyses. Objective: The genetic evaluation of Santa Inês sheep was performed for resistance to gastrointestinal nematode infection (RGNI) and body size using different relationship matrices to assess the efficiency of including genomic information in the analyses.Methods: There were 1,637 animals in the pedigree and 500, 980, and 980 records of RGNI, thoracic depth (TD), and rump height (RH), respectively. The genomic data consisted of 42,748 SNPs and 388 samples genotyped with the OvineSNP50 BeadChip. The (co)variance components were estimated in single- and multi-trait analyses using the numerator relationship matrix (A) and the hybrid matrix H, which blends A with the genomic relationship matrix (G). The BLUP and single-step genomic BLUP methods were used. The accuracies of estimated breeding values and Spearman rank correlation were also used to assess the feasibility of incorporating genomic information in the analyses.Results: The heritability estimates ranged from 0.11±0.07, for TD (in single-trait analysis using the A matrix), to 0.38±0.08, for RH (using the H matrix in multi-trait analysis). The estimates of genetic correlation ranged from –0.65±0.31 to 0.59±0.19, using A, and from –0.42±0.30 to 0.57±0.16 using H. The gains in accuracy of estimated breeding values ranged from 2.22% to 75.00% with the inclusion of genomic information in the analyses.Conclusion: The inclusion of genomic information will benefit the direct selection for the traits in this study, especially RGNI and TD. More information is necessary to improve the understanding on the genetic relationship between resistance to nematode infection and body size in Santa Inês sheep. The genetic evaluation for the evaluated traits was more efficient when genomic information was included in the analyses.

A micro-computed tomographic study using a novel test model to assess the filling ability and volumetric changes of bioceramic root repair materials

Torres Fernanda Ferrari Esteves,Pinto Jader Camilo,Figueira Gabriella Oliveira,Guerreiro-Tanomaru Juliane Maria,Tanomaru-Filho Mario 대한치과보존학회 2021 Restorative Dentistry & Endodontics Vol.46 No.1

Objectives: New premixed bioceramic root repair materials require moisture for setting. Using micro-computed tomography (micro-CT), this study evaluated the filling ability and volumetric changes of calcium silicate-based repair materials (mineral trioxide aggregate repair high-plasticity [MTA HP] and Bio-C Repair, Angelus), in comparison with a zinc oxide and eugenol-based material (intermediate restorative material [IRM]; Dentsply DeTrey). Materials and Methods: Gypsum models with cavities 3 mm deep and 1 mm in diameter were manufactured and scanned using micro-CT (SkyScan 1272. Bruker). The cavities were filled with the cements and scanned again to evaluate their filling capacity. Another scan was performed after immersing the samples in distilled water for 7 days to assess the volumetric changes of the cements. The statistical significance of differences in the data was evaluated using analysis of variance and the Tukey test with a 5% significance level. Results: Bio-C Repair had a greater filling ability than MTA HP (p < 0.05). IRM was similar to Bio-C and MTA HP (p > 0.05). MTA HP presented the largest volumetric change (p < 0.05), showing more volume loss than Bio-C and IRM, which were similar (p > 0.05). Conclusions: Bio-C Repair is a new endodontic material with excellent filling capacity and low volumetric change. The gypsum model proposed for evaluating filling ability and volumetric changes by micro-CT had appropriate and reproducible results. This model may enhance the physicochemical evaluation of premixed bioceramic materials, which need moisture for setting.

Hospitality Service Innovation: KLEEDing an Outstanding Guest Experience

Torres, Arnelyn Manaluz,말런 사이프 차세대컨버전스정보서비스학회 2020 차세대컨버전스정보서비스기술논문지 Vol.9 No.2

The paper proposes to innovate service strategies following the KLEED model that expands to the attributes for the outstanding guest experience. The study is based on a review of academic literature, business news reports and online resources regarding human touch and technology the hotel industry is using. The suggestions were drawn from the authors’ guest journey experience while staying in different hotels. Human touch or personal interaction is an integral part of the hospitality service business, and should never be set aside. In the same way for technology, adopting it contributes to the value creation of the hospitality business resulting in greater guest satisfaction. Thus, a blend of human touch and technology turns out to be the main ingredients for the outstanding guest experience. This paper used the authors’ experience as hotel guests and other business reports to draw suggestions on how a blended service will create outstanding guest experience.