Preparation of Protoplasts from Porphyra, Macrocyctis, and Ulva

Daniel A. Coury 부산수산대학 해양과학연구소 1992 연구논문집-부산수산대학교 해양과학공동연구소 Vol.24 No.-

An Instrumented Workstation to Evaluate Weight-Bearing Distribution in the Sitting Posture

Moriguchi, Cristiane S.,Sato, Tatiana O.,Coury, Helenice J.C.G. Occupational Safety and Health Research Institute 2019 Safety and health at work Vol.10 No.3

Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weight-bearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures ($p{\geq}0.40$), errors were less than 2% of participant weights an sensitivity presented statistically significant changes (p = 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

An Instrumented Workstation to Evaluate Weight-Bearing Distribution in the Sitting Posture

Cristiane S. Moriguchi,Tatiana O. Sato,Helenice J.C.G. Coury 한국산업안전보건공단 산업안전보건연구원 2019 Safety and health at work Vol.10 No.3

Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weightbearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures (p 0.40), errors were less than 2% of participant weights and sensitivity presented statistically significant changes (p ¼ 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

Psychosocial Risk Factors and Musculoskeletal Symptoms among White and Blue-collar Workers at Private and Public Sectors

Leticia B Januario,Mariana V Batistao,Helenice JCG Coury,Ana Beatriz Oliveira,Tatiana O Sato 대한직업환경의학회 2014 대한직업환경의학회지 Vol.26 No.-

Objectives: The aim of this study was to evaluate musculoskeletal and psychosocial perception and compare these conditions regarding the type of job (white or blue-collar) and the type of management model (private or public). Methods: Forty-seven public white-collar (PuWC), 84 private white-collar (PrWC) and 83 blue-collar workers (PrBC) were evaluated. Job Content Questionnaire (JCQ) and Utrecht Work Engagement Scale (UWES) were applied to evaluate psychosocial factors. Nordic Musculoskeletal Questionnaire (NMQ) was used to assess musculoskeletal symptoms. Pressure Pain Threshold (PPT) was measured to evaluate sensory responses. Results: According to JCQ, all groups were classified as active profile. There was a significant association between work engagement and workers’ categories (p < 0.05). PrWC workers had the highest scores for all the UWES domains, while PrBC had the lowest ones. PPT showed that PrBC workers had an increased sensitivity for left deltoid (p < 0.01), and for both epicondyles (p < 0.01), when compared to the other groups. PrWC workers had an increased sensitivity for both epicondyles than PuWC (right p < 0.01; left, p = 0.05). There was no significant association in the report of symptoms across the groups (p > 0.05). Conclusion: This study showed differences in psychosocial risk factors and musculoskeletal symptoms in workers engaged in different types of jobs and work organization. Personal and work-related characteristics, psychosocial factors and PPT responses were different across workers’ group. Despite all, there was no significant difference in reported symptoms across the groups, possibly indicating that the physical load is similar among the sectors.

The influence of nanofillers on the properties of ethanol-solvated and non-solvated dental adhesives

da Cruz, Leonardo Bairrada Tavares,Oliveira, Marcelo Tavares,Saraceni, Cintia Helena Coury,Lima, Adriano Fonseca The Korean Academy of Conservative Dentistry 2019 Restorative Dentistry & Endodontics Vol.44 No.3

Objectives: The aim of this study was to evaluate the influence of different concentrations of nanofillers on the chemical and physical properties of ethanol-solvated and non-solvated dental adhesives. Materials and Methods: Eight experimental adhesives were prepared with different nanofiller concentrations (0, 1, 2, and 4 wt%) and 2 solvent concentrations (0% and 10% ethanol). Several properties of the experimental adhesives were evaluated, such as water sorption and solubility (n = 5, 20 seconds light activation), real-time degree of conversion (DC; n = 3, 20 and 40 seconds light activation), and stability of cohesive strength at 6 months (CS; n = 20, 20 seconds light activation) using the microtensile test. A light-emitting diode (Bluephase 20i, Ivoclar Vivadent) with an average light emittance of $1,200mW/cm^2$ was used. Results: The presence of solvent reduced the DC after 20 seconds of curing, but increased the final DC, water sorption, and solubility of the adhesives. Storage in water reduced the strength of the adhesives. The addition of 1 wt% and 2 wt% nanofillers increased the polymerization rate of the adhesives. Conclusions: The presence of nanofillers and ethanol improved the final DC, although the DC of the solvated adhesives at 20 seconds was lower than that of the non-solvated adhesives. The presence of ethanol reduced the strength of the adhesives and increased their water sorption and solubility. However, nanofillers did not affect the water sorption and strength of the tested adhesives.

Effects of radiant exposure and wavelength spectrum of light-curing units on chemical and physical properties of resin cements

Adriano Fonseca Lima,Stephanie Ellen Ferreira Formaggio,Ligia Franca Aires Zambelli,Alan Rodrigo Muniz Palialol,Giselle Maria Marchi,Cintia Helena Coury Saraceni,Marcelo Tavares de Oliveira 대한치과보존학회 2016 Restorative Dentistry & Endodontics Vol.41 No.4

Objectives: In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs) on the degree of conversion (DC) and the mechanical properties of resin cements. Materials and Methods: Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG), according to the different radiant exposures (5, 10, and 20 J/cm2) and two LCUs (single-peak and polywave). The specimens were made (7 mm in length × 2 mm in width × 1 mm in height) using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E) by a three-point bending test. Data were assessed for normality, after which twoway analysis of variance (ANOVA) and post hoc Tukey’s test were performed. Results: No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions: On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was materialdependent.

Effects of radiant exposure and wavelength spectrum of light-curing units on chemical and physical properties of resin cements

Lima, Adriano Fonseca,Formaggio, Stephanie Ellen Ferreira,Zambelli, Ligia Franca Aires,Palialol, Alan Rodrigo Muniz,Marchi, Giselle Maria,Saraceni, Cintia Helena Coury,de Oliveira, Marcelo Tavares The Korean Academy of Conservative Dentistry 2016 Restorative Dentistry & Endodontics Vol.41 No.4

Objectives: In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs) on the degree of conversion (DC) and the mechanical properties of resin cements. Materials and Methods: Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG), according to the different radiant exposures (5, 10, and $20J/cm^2$) and two LCUs (single-peak and polywave). The specimens were made (7 mm in length ${\times}$ 2 mm in width ${\times}$ 1 mm in height) using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E) by a three-point bending test. Data were assessed for normality, after which two-way analysis of variance (ANOVA) and post hoc Tukey's test were performed. Results: No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions: On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was material-dependent.