• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.4
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• pp.412-420
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• 1991

Seventeen rigid screw fixation and sixteen nonrigid wire fixation cases of mandibular sagittal slit ramus osteotomy were selected to compare postoperative dental and skeletal changes. A constructed horizontal plane was drawn seven degrees under sella-nasion plane and detailed cephalometirc assessment was applied to serial radiographic films taken before surgery($T_0$), immediately after surgery($T_1$), and at least six months after surgery($T_2$). Linear and angular positional changes were measured and analyzed statistically using paired t-test method and percent of positional changes(amount of post-op change/amount of intra-op change)${\times}100$. The results were as follows; 1. It was 29.4% in rigid fixation cases and 37.5% in nonrigid fixation cases comparing the postoperative positional change of more than 2mm at point B. So rigid fixation method was slightly more stable. 2. In nonrigid fixation cases, the positional change might be caused by incomplete bony union at the osteotomy site and soft tissue tension acting on this site. 3. In rigid fixation cases, the positional change might be caused by interaction between relapse tendency of protracted condyle-proximal segment and neighboring soft tissue tension.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.264-271
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• 2013

Purpose: We aimed to analyze the effect of fixation tightness of the syndesmotic screw and its indwelling period on the recurrence of the syndesmosis widening after screw removal and the clinical outcomes. Materials and Methods: Forty consecutive patients with acute syndesmotic injury were retrospectively reviewed. The tibiofibular clear space is measured by digitalized measurement tool on serial radiographs. We analyzed the effect of time from trauma to fixation, syndesmotic screw indwelling duration, and fixation methods. Residual symptoms at the last follow up were evaluated. The student t-test, correlation test, and chi-square test were used for statistical analysis. Results: Eighteen ankles (45%) had recurrent syndesmosis widening (greater than 5% compared to the contralateral side). Seven patients had pain and five had limitation of motion in the ankle joint. Fixation tightness had significant effect on reducing the recurrence while the severity of the initial widening, time to fixation, and duration of fixation did not affect the outcome. Conclusion: Tight fixation of syndesmotic screw is essential for achieving final syndesmotic stability and reducing recurrence.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.1
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• pp.17-29
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• 2016

Though there is an abundant supply of nitrogen in the atmosphere, it cannot be used directly by the biological systems since it has to be combined with the element hydrogen before their incorporation. This process of nitrogen fixation ($N_2$-fixation) may be accomplished either chemically or biologically. Between the two elements, biological nitrogen fixation (BNF) is a microbiological process that converts atmospheric di-nitrogen ($N_2$) into plant-usable form. In this review, the genetics and mechanism of nitrogen fixation including genes responsible for it, their types and role in BNF are discussed in detail. Nitrogen fixation in the different agricultural systems using different methods is discussed to understand the actual rather than the potential $N_2$-fixation procedure. The mechanism by which the diazotrophic bacteria improve plant growth apart from nitrogen fixation such as inhibition of plant ethylene synthesis, improvement of nutrient uptake, stress tolerance enhancement, solubilization of inorganic phosphate and mineralization of organic phosphate is also discussed. Role of diazotrophic bacteria in the enhancement of nitrogen fixation is also dealt with suitable examples. This mini review attempts to address the importance of diazotrophic bacteria in nitrogen fixation and plant growth improvement.

• Journal of Korean Foot and Ankle Society
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• v.13 no.2
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• pp.169-174
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• 2009

Purpose: To evaluate the clinical results between interlocking intramedullary nail with fibular fixation and nail only for treating distal tibiofibular diaphyseal fractures. Materials and Methods: From March 2003 to September 2006, 19 distal tibiofibular fractures were antegrade nailed after anatomical reduction and fixation of fibular fractures, and another 37 fractures fixed with nails only. Average age of patients was 48.6 years. These two groups were compared by VAS (visual analogue scale) & ankle ROM according to degree of comminution and fracture configuration. The statistical analysis was evaluated by t-test. Results: There was no statistical difference between fibular fixation group and non-fixation group in VAS score according to fracture comminution and configuration (p>0.05). However, compared according to fracture configuration, mean ankle eversion of fibular fixation group in oblique fractures was 18.3 degrees, and that of non-fixation group was 12.5 degrees (p<0.05). In addition, mean ankle plantar flexion, dorsiflexion, inversion and total ankle ROM of fibular fixation group in spiral fractures was 40.0, 20.0, 30.0 and 108.3 degrees of each and that of non-fixation group was 38.3, 18.5, 27.0 and 101.7 degrees (p<0.05). Conclusions: In oblique and spiral fractures of distal tibiofibular diaphysis, interlocking intramedullary nail with fibular fixation had the advantage in postoperative ankle ROM. So, it can be a worthy method for the treatment of distal tibiofibular diaphyseal fractures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.6
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• pp.332-336
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• 2012

Objectives: This study sought to evaluate fixation methods and determine the best method for the postoperative stabilization of maxillary osteotomy. For our analysis we performed a three-dimensional finite element analysis of stress distribution on the plate, screw, and surrounding bone, as well as displacement onto the plate. Materials and Methods: We generated a model using synthetic skull scan data; an initital surface model was changed to a solid model using software. Modified anterior segmental osteotomy (using Park's method) was made using the program, and four different types of fixation methods were used. An anterior load of 100 N was applied on the palatal surface of two central incisors. Results: The Type 1 (L-shaped) fixation method gave stresses of 187.8 MPa at the plate, 45.8 MPa at the screw, and 15.4 MPa at the bone around the plate. The Type 2 (I-shaped) fixation method gave stresses of 186.6 MPa at the plate, 75.7 MPa at the screw, and 13.8 MPa at the bone around the plate. The Type 3 (inverted L-shaped) fixation method gave stresses of 28.6 MPa at the plate, 29.9 MPa at the screw, and 15.3 MPa at the bone around the plate. The Type 4 (I-shaped) fixation method gave stresses of 34.8 MPa at the plate, 36.9 MPa at the screw, and 14.9 MPa at the bone around the plate. The deflection of the plates for the four fixation methods was 0.014 mm, 0.022 mm, 0.017 mm, and 0.018 mm, respectively. Conclusion: The Type 3 (inverted L-shaped) fixation method offers more stability than the other fixation methods. We therefore recommend this method for the postoperative stabilization of maxillary osteotomy.

• Textile Coloration and Finishing
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• v.19 no.2
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• pp.14-23
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• 2007

This research article explores the use of phthalocyanine reactive dye on nylon substrate. The effect of factors such as pH, temperature, liquor ratio and alkali addition on level of dye exhaustion, fixation and total fixation efficiency. Low pH, high temperature and low liquor ratio were found to be suitable conditions for maximum % exhaustion values. The effect of sulphatoethylsulphone(SES) and vinylsulphone(VS) form of the dyes on level of dye fixation was also discussed. The optimized exhaustion (%E), fixation(%F) and total fixation efficiency were determined. Modification of the dyeing process with alkali addition displayed that dye fixation(%) increased by alkali addition. Vinylsulphone(VS) moiety of the dye was found to be superior to. maximum fixation (%F). Appropriate predictable empirical models, relatively a new approach in dyeing processes, were developed incorporating interactions effects of temperature, pH and liquor ratio for predicting % exhaustion, fixation and total fixation efficiency. The significance of the mathematical model developed was ascertained using microsoft excel regression(solver) analysis module. High correlation coefficient was obtained (R2=0.9895 for % exhaustion, R2=0.9932 for fixation, R2=0.9965 for total fixation efficiency) for the model which shows prominent prediction capacity of the model for my conditions. The predictable polynomial equations developed from tile experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• Journal of Chest Surgery
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• v.49 no.1
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• pp.1-8
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• 2016

More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950's, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft $f{\ddot{u}}r$ osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has becomeavailable suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.1
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• pp.15-23
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• 2000

Effect of fixation methods on the flame retardant(FR) and performance properties of MDPPA/HMM treated cotton fabrics were studied. Combination of three different fixation methods - premercerization, swelling agent treatment, pad dry cure fixation, and wet fixation - were applied to flame retardant finish of cotton with MDPPA/HMM. As a result, an increase in internal volume of cotton fiber by pre-mercerization and addition of swelling agent, and wet fixation increased %add-on of FR agent improving FR efficiency and wash fastness. Tensile strength of MDPPA/HMM treated cotton fabrics by wet fixation and swelling agent were slightly decreased, but that of premercerized cotton was improved. Wet fixated fabric showed lower bending rigidity and better compressional properties which improved fabric hand. Retention of swelling ability of cotton treated with MDPPA/HMM improved moisture absorption properties.

• Archives of Craniofacial Surgery
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• v.16 no.2
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• pp.96-98
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• 2015

Maxillomandibular fractures usually require intermaxillary fixation as a means to immobilize and stabilize the fracture and to re-establish proper occlusion. Arch bars or intermaxillary fixation screws cannot be used for edentulous patients or for patients who have poor dental health. Here, we present a case of repeated intermaxillary fixation failure in a patient weak alveolar rigidity secondary to multiple dental implants. Because single-point fixation screws were not strong enough to maintain proper occlusion, we have used Y-shaped plates to provide more rigid anchoring points for the intermaxillary wires. We suggest that this method should be considered for patients in whom conventional fixation methods are inappropriate or have failed.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.321-327
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• 2013

Purpose: To investigate a correlation between vertical fixation disparity and stereopsis by analyzing distribution of types of vertical fixation disparity. Methods: In this study, RANDOT(R) stereotest partly using random dot was used in stereopsis tests. The vertical fixation disparity in close proximity categorized fixation disparity slope into six types on the basis of the result of measurement in when two thin lines, one for one eye looks, become overlapped as a line by adding into prism with Wesson fixation disparity card while maintaining a distance of 25 cm from patients. Results: In the types of near vertical fixation disparity curve, targeting 43 people, the first type 55.82% was the most distributed, the second type is the least 23.25%, the third type of 4.65%, the fourth type of 4.65%, the fifth type of 6.98%, the sixths types of 4.65% were distributed. The result of a correlation analysis, which shows the degree of linear correlation between two variables, represented that stereopsis is not correlated with Y-intercept (r = -0.07) which show vertical fixation disparity, associated phoria (r = -0.03) and dissociated phoria (r = -0.00), but it was not statistically significant (p>0.05). Fixation disparity slope of vertical fixation disparity (r = 0.36) was shown to have a positive correlation with stereopsis. It has a low positive correlation and a meaningful statistics (p<0.05). The Y-intercept which indicates vertical fixation disparity was also not associated with stereopsis (r = -0.07) and dissociated phoria (r = -0.03), and this was not statistically significant (p>0.05), while it had a high correlation as well as a statistically significant with associated phoria (r = 0.89). There was a negative correlation between Y-intercept and fixation disparity slope of vertical fixation disparity (r = -0.33). It showed a low relationship but statistically valuable (p>0.05). As a result of regression analysis, the stereopsis was changed as 7.631" if vertical fixation disparity changes 1' and the vertical fixation disparity changed as 0.017' if stereopsis changes 1', and the change was statistically significant (p<0.05). Conclusions: The study shows that there is a low correlation between stereopsis and vertical fixation disparity, and it is difficult to determine stereopsis only using vertical fixation disparity. Therefore, it suggests other factors above vertical fixation disparity have greater influence on stereopsis.