Layperson assessment of smile lines and upper lip combined images in smile esthetics.

STATEMENT OF PROBLEM: The esthetic assessment of smile lines by laypersons is a subject of ongoing debate. However, smile lines often appear with different types of upper lip curvature, which further complicates the esthetic assessment process, and studies on this combination are lacking. PURPOSE: The purpose of this clinical study was to investigate a layperson's esthetic perception of smile lines and upper lip combined images. MATERIAL AND METHODS: Twenty-six smile images resulting from combinations of 3 upper lip types, 4 anterior smile line types, and 3 posterior smile line types were generated by an image editing software program. Eighty-three laypersons (39 men and 44 women; 18 to 35 years of age) completed rating images using a visual analog scale. Unattractive smiles were designated to be those with scores <50 and attractive ones with scores ≥50. Data were analyzed using 1-way analysis of variance and Bonferroni post hoc tests (α=.05). RESULTS: High anterior smile line with gingival display >4 mm obtained significantly lower scores of <50 when combined with all upper lip curvatures (upward: 28.29 ±22.79, straight: 38.74 ±23.00, downward: 30.67 ±22.25, P<.01). High anterior smile lines with gingival display ≤4 mm combined with upward and straight upper lip curvature images obtained significantly higher scores, and all were ≥50 (upward: 63.24 ±22.22, straight: 61.40 ±21.58, P<.01). CONCLUSIONS: From a layperson's perspective, high anterior smile lines with gingival display >4 mm combined with any lip type were determined to be unattractive. If gingival display was ≤4 mm combined with both upward and straight lip types, the smile was assessed as attractive.

Fiber laser spot welding of molybdenum alloy in a hyperbaric environment.

The effect of the growth of ambient pressures on the penetration of laser welded molybdenum (Mo) alloy was explored. It was found that when ambient pressure rose from 0.1 MPa to 1.8 MPa, the penetration of base metal (BM) was significantly reduced, which was only 17% of that obtained under ambient pressure of 0.1 MPa. Moreover, the mechanism underlying the significant reduction of the penetration of BM was analyzed. At first, by using a high-resolution scanning electron microscope (SEM), the size and the number of nano-sized metallic particles generated during laser welding under different ambient pressures were surveyed. Furthermore, the scattering and absorption of the nano-sized metallic particles for laser energy under different ambient pressures were investigated; afterwards, by applying a high-speed camera and a spectrometer, the transient behaviors and spectral signals of plasmas during fiber laser spot welding under different ambient pressures were monitored. On this basis, the inverse bremsstrahlung absorption of plasmas for laser energy under different ambient pressures was explored; finally, fiber laser spot welding test was carried out on glass/metal composite samples under different ambient pressures to survey the influence of the change of ambient pressure on dynamic behaviors of the molten pool during the welding.

Motor Bur Milling State Identification via Fast Fourier Transform Analyzing Sound Signal in Cervical Spine Posterior Decompression Surgery.

OBJECTIVES: To investigate the real-time sensitive feedback parameter of the motor bur milling state in cervical spine posterior decompression surgery, to possibly improve the safety of cervical spine posterior decompression and robot-assisted spinal surgeries. METHODS: In this study, the cervical spine of three healthy male and three healthy female pigs were randomly selected. Six porcine cervical spine specimens were fixed to the vibration isolation system. The milling state of the motor bur was defined as the lamina cancellous bone (CA), lamina ventral corticalbone (VCO), and penetrating ventral cortical bone (PVCO). A 5-mm bur milled the CA and VCO, and a 2-mm bur milled the VCO and PVCO. A miniature microphone was used to collect the sound signal (SS) of milling lamina which was then extracted using Fast Fourier Transform (FFT). When using 5-mm and 2-mm bur to mill, the CA, VCO, and PVCO of each specimen were continuously collected at 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 kHz frequencies for SS magnitudes. The study randomly selected the SS magnitudes of the CA and VCO continuously for 2 s at 1, 2, 3, 4, and 5 kHz frequencies for statistical analyses. When milling the VCO to the PVCO, we randomly collected the SS magnitudes of the VCO for consecutive 2 s and the SS magnitudes of continuous 2 s in the penetrating state at 1, 2, 3, 4, and 5 kHz frequencies for statistical analyses. The independent sample t-test was used to compare the SS magnitudes of different milling states extracted from the FFT to determine the motor bur milling state. RESULTS: The SS magnitudes of the CA and VCO of all specimens extracted from the FFT at 1, 2, and 3 kHz were statistically different (P < 0.01); three specimens were not statistically different at a specific FFT-extracted frequency (first specimen at 5 kHz, SS magnitudes of the CA were [25.94 ± 8.74] × 10-3 , SS magnitudes of the VCO were [28.67 ± 12.94] × 10-3 , P = 0.440; second specimen at 4 kHz, SS magnitudes of the CA were [23.79 ± 7.94] × 10-3 , SS magnitudes of the VCO were [24.78 ± 4.32] × 10-3 , P = 0.629; and third specimen at 5 kHz, SS magnitudes of the CA were [16.76 ± 6.20] × 10-3 , SS magnitudes of the VCO were [17.69 ± 6.44] × 10-3 , P = 0.643).The SS magnitudes of the VCO and PVCO of all the specimens extracted from the FFT at each frequency were statistically different (P < 0.001). CONCLUSIONS: Based on the FFT extraction, the SS magnitudes of the motor bur milling state between the CA and VCO, the VCO and PVCO were significantly different, confirming that the SS is a potential sensitive feedback parameter for identifying the motor bur milling state. This study could improve the safety of cervical spine posterior decompression surgery, especially of robot-assisted surgeries.

Influence of Temperature and Sodium Sulfate Content on the Compaction Characteristics of Cement-Stabilized Macadam Base Materials.

This paper describes an experimental investigation into the compaction characteristics of cement-stabilized macadam base materials (CSMBM) in a saline soil area. Through the field tests, the main causes of arch expansion in an existing road were analyzed. Based on this, the compaction tests and microscopic tests were designed to analyze the impacts of temperature, sodium sulfate content and cement content on the compaction characteristics of CSMBM. Then, the orthogonal test was designed to analyze the effects of the degree of the temperature, the cement content, and the sodium sulfate content on the compaction results of the CSMBM. Feld tests results show that the temperature, sodium sulfate content and cement content may be the main causes of arch expansion. The compaction tests show that with the temperature increasing, the optimal water content (OWC) decreases, but the maximum dry density (MDD) increases; with the sodium sulfate content increasing, the OWC increases, but the MDD decreases; with the cement content increasing, both MDD and OWC increase. The microscopic tests show that the increase of temperature and cement content is beneficial to the compactness between cementitious materials and aggregates, while the increase of sodium sulfate content makes the whole structure of cementitious materials and aggregates increasingly rough. The orthogonal test shows that the temperature has the greatest influence on the MMD, and the sodium sulfate content has the greatest influence on the OWC. Thus, in a sulfate saline soil area, the construction temperature, the sodium sulfate content and the cement content should be controlled to ensure the compaction quality of CSMBM.

Tyrosinase inhibitory effects and antioxidative activities of novel cinnamoyl amides with amino acid ester moiety.

Nine cinnamoyl amides with amino acid ester (CAAE) moiety were synthesized by the conjugation of the corresponding cinnamic acids (cinnamic acid, 4-hydroxy cinnamic acid, ferulic acid and caffeic acid) with amino acid esters, and their inhibitory effects on the activities of mushroom tyrosinase were investigated, using l-3,4-dihydroxyl-phenylalanine (l-DOPA) as the substrate. Among these CAAE amides, ethyl N-[3-(4-hydroxy-3-methoxyphenyl)-1-oxo-2-propen-1-yl]-l-phenylalaninate (b(4)) showed the strongest inhibitory activity; the IC(50) was 0.18 µM. The IC(50) values, inhibition types, inhibition mechanisms and kinetics of all these CAAE amides were evaluated. A structure-activity relationship (SAR) study found that the inhibitory effects were potentiated with the increasing length of hydrocarbon chains at the amino acid esters and also influenced by the substituents at the styrene groups. Furthermore, the hydroxyl radical scavenging and anti-lipid peroxidation activities of four CAAE derivatives were also investigated. Among these compounds, b(3) (ethyl N-[3-(3,4-dihydroxyphenyl)-1-oxo-2-propen-1-yl]-l-phenylalaninate) and b(4) exhibited potential antioxidant activities.

[Acceptability and related factors on male circumcision among young men with Yi ethnicity in one county of Sichuan province.].

OBJECTIVE: To explore the acceptability of male circumcision (MC) as an HIV prevention method and its related factors among young men of Yi ethnicity in Liangshan prefecture. METHODS: 446 young men were selected in Butuo county, under stratified sampling method. Using a self-designed questionnaire, face to face interviews were taken to collect HIV-related risk behaviors, knowledge and acceptability of MC. RESULTS: After an introduction on MC by interviewers, 40.6% of the interviewees expressed their willingness in taking this surgery. The main reason for acceptance was that they felt this surgery might reduce the risk of HIV infection (90.1%). For those who refused to take this surgery, most of them thought it was too sensitive and embarrassing (52.5%) and were afraid that it might affect their procreation ability. Data from logistic regression analysis indicated that the acceptability of MC was associated with the following factors as:age, income, experience of commercial sexual behavior. They also felt that messages related to male MC surgery could reduce the risk of being infected with HIV/STDs or induce pain when having sexual intercourse, or it might cause partial infection after surgery, or they might be mocked at if taking the surgery. CONCLUSION: It is the prerequisite in helping young people of Yi ethnicity to have a good understanding on MC as for Yi people, embarrassment attitudes towards sex appears to be one of the big obstacles against the popularization of this surgery. The operation should be provided by trained and professional doctors, with standardized procedure, in good sanitary conditions and free for service.