• Journal of Biosystems Engineering
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• v.1 no.1
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• pp.17-48
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• 1976

In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic\ulcorneriency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet\ulcornerween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr\ulcornerease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$ $$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$ The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$ These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea\ulcornerses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin\ulcornerear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num\ulcornerber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco\ulcornervery rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.62.1-62.7
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• 2020

A 5-month old Shih Tzu was diagnosed with congenital elbow luxation and uniapical complex angular deformity of the radius. Single radial oblique and dynamic ulnar osteotomies were performed, using patient-specific 3D-printed osteotomy guide. External skeletal fixation was maintained for three weeks to prevent re-luxation of elbow joint. Three months after the surgery, objective gait analysis indicated markedly improved limb function. In addition, radiograph showed improved congruity of elbow joint and appropriate bone healing. In dogs with congenital radial head luxation and concurrent complex angular deformity, a single oblique osteotomy might be a viable option to preserve bone length and correct the luxation of elbow joint.

• Archives of Craniofacial Surgery
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• v.24 no.1
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• pp.28-31
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• 2023

The radial forearm free flap (RFFF) has become popular for head and neck reconstructions. Owing to a constant anatomy the RFFF is relatively easy to dissect. Nevertheless, anatomical variations of the radial artery have been reported. Some variations could affect the survival of the flap. This paper reports an unusual anomaly of the radial artery where the radial artery was not located between the brachioradialis (BR) and flexor carpi radialis. The radial artery was observed above the BR and on the radial side of the BR. The survival of the elevated flap was deemed questionable because it had only few perforators. So we decided to discard the flap and to elevate another free flap for the head and neck defect. The donor area on the forearm was covered using the original skin of the first flap as a full-thickness skin graft. This case highlights a means to deal with anomalies of the radial artery encountered during the elevation of RFFF and the checking process for variations of the radial artery before RFFF.

• Journal of Veterinary Clinics
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• v.34 no.4
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• pp.287-290
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• 2017

A 6-month-old, 4.1 kg female Dachshund dog presented with intermittent non-weight bearing lameness of the right thoracic limb. Radiographs revealed caudolateral luxation of the right radial head and a shortened right ulna compared to the contralateral limb. Bone lengthening by distraction of the ulna using the Ilizarov technique was performed following ulnar osteotomy. The rate of distraction was 1.5 mm per day, adjusted a total of 3 times daily for a total distraction distance of 10 mm. The Ilizarov fixator was removed four weeks after surgery. The patient showed knuckling due to radial nerve injury that occurred during limb-lengthening. Corrective osteotomy was performed using a plate and pin for the luxation and deformity of the right radial head. The luxation of the radial head was successfully reduced following surgery. However, the knuckling persisted after surgery. Rehabilitation for radial nerve injury was performed using heat therapy, massage, a passive range of motion exercises, water treadmill exercises, neuromuscular electrical stimulation, leash-walking, and acupuncture. 15 months after surgery, the patient showed satisfactory weight-bearing ambulation without recurrence of lameness. The use of the Ilizarov technique is a good surgical option for the treatment of a patient with congenital elbow luxation.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2005.03a
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• pp.81-81
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• 2005

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2007.03a
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• pp.176-176
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• 2007

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.75-80
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• 2006

Purpose: To evaluate the efficiency of Acutrak screw fixation for radial head fracture (Mason type 2) without considering the safe Bone of radial head. Materials and Methods: Consecutive seven radial head fracture of Mason type II underwent internal fixation with Acutrak screws from May 2001 to February 2003. The mean follow-up period was 1.2years (ranged, $6 months{\sim}2.5 years$). The mean age of patients was 47 years old (ranged, $36{\sim}60years$ old). The cause of injury were fall down -4 cases and traffic accident -3 cases. The results were evaluated by Mayo Clinic results scoring system. Results: Functional Rating Index of Mayo Clinic was excellent- 2 cases and good- 5 cases. There were no nonunion, loosening, heterotopic ossification, infection or degenerative changes. The postoperative range of motion in elbow joint is nearly full for flexion, extension, pronation and supination in this study Conclusion: Consideration of safe zone is not necessary when Acutrak screws are used for radial head fracture. It seems to be a useful method that Acutrak screw fixation for radial head fracture (Mason type II) could achieve good radiologic and clinical results without influencing proximal radio-ulnar joint and has powerful fixation.

• Korean Journal of Head & Neck Oncology
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• v.31 no.1
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• pp.5-8
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• 2015

Backgrounds: The purpose of this study was to compare full thickness skin graft with inguinal skin to split thickness skin graft for coverage of the radial forearm free flap donor site. Patients and Methods: 25 patients who was reconstructed with radial forearm free flap for head and neck cancer were reviewed retrospectively. Results: The graft loss rates of full thickness skin graft were less than split thickness skin graft or split thickness skin graft with dermal substitutes. The recovery times of donor site and skin graft donor site of full thickness skin graft were also shorter than split thickness skin graft or split thickness skin graft with dermal substitutes. Skin texture and aesthetic results of donor site were improved and complications as itching and pain sensation were decreased. Conclusion: Full thickness skin grafts with inguinal skin should be considered for patients requiring a radial forearm free flap.

• Archives of Craniofacial Surgery
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• v.22 no.1
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• pp.38-44
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• 2021

Background: The free flap surgical method is useful for the reconstruction of head and neck defects. This study retrospectively analyzed the results of head and neck reconstructions using various types of free flaps over the past 30 years. Methods: Between 1989 and 2018, a total of 866 free flap procedures were performed on 859 patients with head and neck defects, including 7 double free flaps. The causes of vascular crisis and salvage rate were analyzed, and the total flap survival rate calculated among these patients. Additionally, the survival and complication rates for each flap type were compared. Results: The 866 cases included 557 radial forearm flaps, 200 anterolateral thigh flaps, 39 fibular osteocutaneous flaps, and 70 of various other flaps. The incidence of the vascular crisis was 5.1%; its most common cause was venous thrombosis (52.3%). Salvage surgery was successful in 52.3% of patients, and the total flap survival rate was 97.6%. The success rate of the radial forearm flap was higher than of the anterolateral flap (p< 0.01), and the primary sites of malignancy were the tongue, tonsils, and hypopharynx, respectively. Conclusion: The free flap technique is the most reliable method for head and neck reconstruction; however, the radial forearm free flap showed the highest success rate (98.9%). In patients with malignancy, flap failure was more common in the anterolateral thigh (5.5%) and fibular (5.1%) flaps.

• Archives of Plastic Surgery
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• v.48 no.6
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• pp.646-650
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• 2021

Head and neck reconstruction poses unique challenges in rehabilitating surgical defects in terms of integrity, function, and form. The radial forearm free flap (RFFF) has been widely used for defect coverage, especially in the head and neck area, but its versatility allows it to be used for soft-tissue reconstruction in various parts of the body. The vascular features of the flap are quite constant and reliable. Nevertheless, abnormalities of the forearm vascular tree have been described over the decades. We report a case of intraoral reconstruction after verrucous carcinoma recurrence in a 74-year-old woman with an unusual forearm flap, which we called the median forearm free flap, based on a median branch of the radial artery that was preoperatively detected using handheld Doppler ultrasonography. The distally located skin paddle was predominantly supplied by the aberrant median vessel with its perforators. The flap was thus safely harvested with this atypical pedicle. Successful reconstruction of the intraoral defect was achieved, with an uneventful postoperative course.