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Since its discovery almost 70 years ago, the hologram has been considered to reproduce the most realistic three dimensional images without visual side effects. Holographic video has been extensively researched for commercialization, since Benton et al. at MIT Media Lab developed the first holographic video systems in 1990. However, commercially available holographic video displays have not been introduced yet for several reasons: narrow viewing angle, bulky optics and heavy computing power. Here we present an interactive slim-panel holographic video display using a steering-backlight unit and a holographic video processor to solve the above issues. The steering-backlight unit enables to expand the viewing angle by 30 times and its diffractive waveguide architecture makes a slim display form-factor. The holographic video processor computes high quality holograms in real-time on a single-chip. We suggest that the slim-panel holographic display can provide realistic three-dimensional video in office and household environments.
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The thenar flap is a well-described technique, but reports about its use in patients with multiple fingertip injuries are limited. This study aims to introduce a surgical technique of using an extended thenar flap for two adjacent fingertip amputations and to evaluate the clinical outcomes and related complications. From October 2013 to October 2016, 12 patients (24 fingers) underwent soft tissue reconstruction of two adjacent fingers with an extended thenar flap. At the last follow-up, the patients were assessed for cold intolerance in the reconstructed fingers; two-point discrimination (2PD); range of motion (ROM); functional outcomes using the quick disabilities of the arm, shoulder, and hand (DASH) score; functional and appearance outcomes using the Michigan Hand Outcome Questionnaire (MHQ); and time taken to return to work. The mean follow-up time was 13.5 (range: 12-16) months. All flaps survived. The mean total active ROM in flexion measured at the last follow-up was 255° (range: 245°-260°). Objective sensibility in the flaps was ascertained as an average static 2PD of 6.9 (range: 3-10) mm. The mean quick DASH score was 3.3 (range: 0-9.1). The mean MHQ score was 93.8 (range: 88-100). All patients returned to work within 6.2 weeks on average. There were no complications. The extended thenar flap technique is a good alternative for simultaneous coverage of small-to-large defects in two adjacent fingertips.
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Amputación Traumática/cirugía , Traumatismos de los Dedos/cirugía , Dedos/cirugía , Colgajos Quirúrgicos , Accidentes de Trabajo , Adulto , Cuidados Posteriores , Amputación Traumática/fisiopatología , Femenino , Traumatismos de los Dedos/fisiopatología , Supervivencia de Injerto/fisiología , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular/fisiología , Sensación , Técnicas de Sutura , Sitio Donante de Trasplante/fisiología , Resultado del TratamientoRESUMEN
Along with the increasing demand for the TiO2 pigment, the ilmenite smelting process has also become significant because it can utilize both rock- and sand-type ilmenite. However, due to the high liquidus temperature of the TiO2 slag system, the smelting process is highly energy consuming. In the present study, the viscosity of molten ilmenite slag was estimated using molecular dynamic simulations at a high temperature to achieve an appropriate and efficient slag design. To verify the validity of the simulation technique, experimental measurements were performed in parallel and their results were compared. The effects of FeO and Na2O addition on viscosity of TiO2 slag were also investigated. The addition of Na2O as a flux enhanced the ilmenite smelting process by not only lowering the liquidus temperature but also slowing the drastic viscosity increase. Statistical information obtained from the molecular dynamic simulations revealed a three-dimensional TiO6 octahedral network structure. The relationship between viscosity and structural change with varying FeO and Na2O concentrations was explored considering the coordination number of Ti and various bonding types.
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Although there have been various attempts to identify the perceptual-cognitive mechanisms underlying the superior performance of skilled players over novices in sports, few studies have examined the relationship between mental representations and cognitive performance according to the skill levels of players. The purpose of this study was to investigate the functional link between mental representations in long-term memory and cognitive information processing ability in working memory by analyzing mental representation structure and cognitive performance according to skill level. Twenty male skilled and 25 male novice tennis players participated in this study. Structural dimensional analysis of mental representation was used to evaluate the mental representation structure of a tennis serve. In addition, cognition and movement chronometry was used to assess the cognitive performance of a tennis serve in working memory. Results of the representational analysis showed that the similarity of the skilled players to the standard representation structure was higher than that of novices. Furthermore, results in cognitive performance showed that the skilled players had a higher accuracy and shorter response time compared to the novices. Finally, a significant correlation between the adjusted Rand index and cognition movement chronometry accuracy was observed. Taken together, the mental representation structure and cognitive performance of the skilled players were superior to those of the novices, and mental representations were positively correlated with the accuracy of the cognitive information processing. These results imply that the degree of functional connection between working memory and long-term memory may be used as a perceptual-cognitive factor to explain improvement in performance.
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A retrospective radiographic study was conducted from five private dental offices on patients requesting dental implant therapy to replace their missing teeth. All implants were placed and restored by early 2000, and patients were encouraged to continue their dental care at the same office. The records were reviewed and analyzed by the clinicians, who had more than 15 years of dental experience at the time of the initial patient treatment. A total of 74 patients with 242 implants were recalled up to 10 years (mean follow-up: 9.21 ± 1.7 years) after loading. There were five implant failures from this radiographic observation period, resulting in a 97.9% dental implant survival rate. The mean crestal bone level change on the mesial aspect was -0.36 ± 1.05 mm, while the mean crestal bone level change on the distal aspect was -0.18 ± 0.96 mm. Thus, the overall mean bone loss was -0.28 ± 0.05 mm. The dental implants, which had a sandblasted, large-grit, acid-etched surface, appeared to achieve successful osseointegration in this long-term observation period, and the implant system's unique design and surface features resulted in a stable osseous crest without bone loss to the first thread.
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Implantes Dentales , Estudios de Seguimiento , Humanos , Falla de Prótesis , Estudios RetrospectivosRESUMEN
PURPOSE: The purpose of this prospective study was to evaluate the effect of early loading on survival rate or clinical parameter of anodic oxidized implants during the 12-month postloading period. MATERIALS AND METHODS: Total 69 implants were placed in 42 patients. Anodic oxidized implants (GS II, Osstem Cor., Busan, Korea) placed on the posterior mandibles were divided into two groups, according to their prosthetic loading times: test group (2 to 6 weeks), and control group (3 to 4 months). The implant survival rates were determined during one-year postloading period and analyzed by Kaplan-Meier method. The radiographic peri-implant bone loss and periodontal parameters were also evaluated and statistically analyzed by unpaired t-test. RESULTS: Total 69 implants were placed in 42 patients. The cumulative postloading implant survival rates were 88.89% in test group, compared to 100% in control group (P<.05). Periimplant marginal bone loss (T: 0.27±0.54 mm, C: 0.40±0.55 mm) and periodontal parameters showed no significant difference between the groups (P>.05). CONCLUSION: Within the limitation of the present study, implant survival was affected by early loading on the anodic oxidized implants placed on posterior mandibles during one-year follow-up. Early implant loading did not influence peri-implant marginal bone loss, and periodontal parameters.
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Cranial sutures are an important growth center of the cranial bones, and the suture space must be maintained to permit the cranial adjustments needed to accommodate brain growth. Craniosynostosis, characterized by premature suture closure, mainly results from mutations that generate constitutively active fibroblast growth factor (FGF) receptors. FGF signaling, thus, is responsible for the pathogenesis of craniosynostosis. Even though FGF activates many different signaling pathways, the one involved in premature suture closure has not been defined. We observed that placing FGF2-soaked bead on the osteogenic fronts of cultured mouse calvaria accelerates cranial suture closure and strongly induces the expression of osteopontin, an early marker of differentiated osteoblasts. FGF2 treatment also induced fos and jun mRNAs and later increased the nuclear levels of activator protein 1 (AP1). FGF2 stimulates the expression of osteopontin by inducing expression of AP1, which then binds to its response element in the osteopontin promoter. Blocking of the Erk pathway by PD98059 suppressed the AP1 and osteopontin expression stimulated by FGF2. Coincidently, blocking of the Erk pathway also significantly retarded FGF2-accelerated cranial suture closure. Thus, the Erk pathway mediates FGF/FGF receptor-stimulated cranial suture closure, probably by stimulating synthesis of AP1 that then stimulates the differentiation of osteoblasts.