• Title/Summary/Keyword: EAR

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The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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A Survey on the Hearing Disturbance of High School Students in Korea (한국고교생(韓國高校生)에 대(對)한 난청실태조사(難聽實態調査))

  • Rhee, Kyu-Shik;Kim, Doo-Hie
    • Journal of Preventive Medicine and Public Health
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    • v.5 no.1
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    • pp.115-123
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    • 1972
  • As a link of chain study program of school health, a survey was made up by the screening test with audiometry for hearing disturbance on 18,675 high school students who are mainly aged in 15-19 years from November 5.1969 to October 30. 1970. The results obtained were summerized as follows. According to our criteria as table 3, the rates of the profound, the severe and the moderate who required the appropriate hearing aids were 0.02%, 0.03% and 0.14% respectively:-the cumulative percentage was 0.197. When the marginal, 0.23% should be included the cumulative rate was 0.41%. But there was no-significance by sex and school classes. If we will make the special classes for them one class would be estimated out of 10,000 persons when a class is formed with about 15 persons. Otherwise when we examined that according to each ear of persons, the rates of the profound, the severe and the moderate were 0.17%, 0.22% and 0.33% respectively and their cumulative percentage wag 0.72. There was no significance also by sex and age. By the way, the rate of hearing disturbance in urban high school students tended to lower than rural. And the perceptive disturbance was higher than rural in rate. The conductive disturbance tended to oppose in comparison with the above.

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Nutritional Risks Analysis Based on the Food Intake Frequency and Health-related Behaviors of the Older Residents (50 Years and Over) in Andong Area (1) (안동주변 농촌지역 50세 이상 주민의 식품섭취빈도 및 건강행위에 따른 영양위험 분석 (1))

  • Lee, Hye-Sang;Kwun, In-Sook;Kwon, Chong-Suk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.8
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    • pp.998-1008
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    • 2008
  • This study aimed to assess the nutritional status and the nutritional risks based on the food intake frequency and health-related behaviors of middle-aged and elderly people living in Andong area. Interviews were conducted with 1,384 subjects (532 males, 852 females) aged 50 years and over. Nutrient intakes, food intake frequency, and health-related behaviors including smoking, drinking, and exercise were investigated. The average energy intakes were 1410.5 kcal for males and 1279.2 kcal for females, and the percentages of the subjects consuming below the estimated energy requirement (EER) were 92.5% and 88.4%, respectively. The least consumed nutrients compared to the estimated average requirement (EAR) were riboflavin (92.5% for males, 89.6% for females), folic acid (89.7%, 88.5%), and calcium (78.9%, 85.8%), in order. According to the food intake frequency survey, the intakes of meat, fish and vegetable (except kimchi) were very poor, and this low intakes of meat and fish showed as poor status of protein, niacin, vitamin $B_6$, and zinc intakes. Health-related behaviors data showed that the ratio of cigarette smokers, especially male, was higher, while the ratio of the person exercising regularly was lower than that of the nationwide statistics, respectively. Cigarette smoking and drinking were not significantly related to the poor nutrition intake, while regular exercise positively influenced nutrient intakes in female subjects. These results showed that the nutritional status of the subjects was likely to be severely deficient and the low intakes of meat and fish to be highly related to the increase of nutritional risk. Therefore, in order to prevent the occurrence of the secondary disease related to the food intake and health-related behaviors of the subjects, the proper educational program on balanced dietary intake and the correction of health-related behaviors should be developed and applied to this area.

Diagnosis of the Field-grown Rice Plant -II. Diagnosis by total plant analysis (포장재배(圃場栽培) 수도(水稻)의 영양진단(營養診斷) -II. 전분석(全分析)에 의(依)한 진단(診斷))

  • Park, Hoon;Park, Chon Suh
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.3
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    • pp.165-172
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    • 1973
  • The optimum time for nutritional diagnosis of the field-grown rice plant by total plant analysis, and the relationship between maximum or minimum nutrient content at various growth stages and corresponding yield and between maximum or minimum yield and corresponding nutrient content were as follows. 1. The percentage occurence of the minimum nutrient content in straw or grain of minus nutrient plot was in the order of 20 days after transplanting (20)>maximum tillering (MT)>harvested straw (HS)> earformation (EF)>straw at flowering (FS)>harvested grain (HG)>ear at flowering (FE) for nitrogen, MT>EF>HS>20=FS>FE>HG for phosphorus and MT>EF>20>FS>HG>FE for potassium. 2. The time when the occurece of minimum nutrient content in minus plot is highest was considered as the optimum time for nutritional diagnosis of root zone. It was 20 days after transplanting in N and maximum tillering stage in P and K. 3. The highest relative difference($100{\times}(L-H)/H$), between maximum (H)and minimum(L) nutrient content appeared in harvested straw for N and P while in harvested grain for K and Si, suggesting the close relation to their translocation from straw to grain. 4. The corresponding yield of maximum nutrient content was higher than that of minimum content at all growth stages in N, at all stages except MT and EF in P, at 20 days after trans planting and harvest in K, but it was always lower in Si, thus the contribution of nutrient content to yield will be in the order of N>P>K>Si. 5. The highest relative difference ($100{\times}(L-H)/H$, where H and L stand for yields) between yields corresponding to maximum and minimum nutrient content appeared at 20 days after transplanting for N. P. K, indicating the time of the closest relation between yield and nutrient content. 6. The highest difference (H-L, where H and L stand for nutrient content) between N. P. K contents corresponding to maximum or minimum yields came at 20 days after transplanting. The contents of N. P. K corresponding to the maximum total dry matter yield were lower than those corresponding the maximum grain yield at this stage. These facts support the closest relation between yield and nutrient content at this time. 7. The highest yield among yields corresponding to maximum nutrient contents occured at 20 days after transplanting in N. P. K but the lowest yield among yields corresponding to minimum nutrient contents appeared at the same stage only in nitrogen. 8. From the above facts the optimum time for diagnosis of nutrient around root zone seems different from that for diagnosis of nutritional status in relation to grain yield.

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Assessment of Nutrient Intakes of Lunch Meals for the Aged Customers at the Elderly Care Facilities Through Measuring Cooking Yield Factor and the Weighed Plate Waste (조리 중량 변화 계수 및 잔반계측법을 이용한 노인복지시설 이용자의 점심식사 영양섭취평가)

  • Chang, Hye-Ja;Yi, Na-Young;Kim, Tae-Hee
    • Journal of Nutrition and Health
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    • v.42 no.7
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    • pp.650-663
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    • 2009
  • The purposes of this study were to investigate one portion size of menus served and to evaluate nutrient intake of lunch at three elderly care facility food services located in Seoul. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Yield factors were calculated from cooking experiments based on standardized recipes, and were used to evaluate nutrient intake. One hundred elderly participated in this study for measuring plate waste and were asked to complete questionnaire. Nutrient analyses for the served and consumed meal were performed using CAN program. The yield factors of rice dishes after cooking are 2.4 regardless of rice dish types, 1.58 for thick soups, 0.60 to 0.70 for meat dishes, and 1.0 to 1.25 branched vegetable. Average consumption quantity of dishes were 235.97 g for rice, 248.53 g for soup, 72.83 g for meat dishes, 39.80 g for vegetables and 28.36 g for Kimchi. On average the food waste rate is 14.0%, indicating the second highest plate waste percentage of Kimchi (26.2%), and meat/fish dish (17.3%). The evaluation results of NAR (Nutrition Adequacy Ratio) showed that iron (0.12), calcium (0.64), riboflavin (0.80), and folic acid (0.97) were less than 1.0 in both male and female elderly groups, indicating significant differences of NAR among three facilities. Compared to the 1/3 Dietary Reference Intake (DRIs) for the elderly groups, nutrient intake analysis demonstrated that calcium (100%) and iron (100%), followed by riboflavin, vitamin A, and Vitamin B6 did not met of the 1/3 EAR (Estimated Average Requirement). For the nutritious meal management, a professional dietitian should be placed at the elderly care center to develop standardized recipes in consideration of yield factors and the elderly's health and nutrition status.

Nutritional Status and Health Risks of Low Income Elderly Women in Gwangju Area (광주지역 저소득층 여자노인의 영양상태와 건강위험요인에 관한 연구)

  • Yang, Eun-Ju;Bang, Hee-Myung
    • Journal of Nutrition and Health
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    • v.41 no.1
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    • pp.65-76
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    • 2008
  • This study was performed to identify association between nutritional status and health risks of the elderly. This was a cross-sectional study involving low income elderly women in Gwangju, Korea (${\geq}$65y, n = 92). Socio-demographics, life style characteristics, health conditions, dietary intakes based on 24h-recall method, anthropometric measures, and clinical biochemistry parameters were examined. Anthropometric and clinical parameters included wt, ht, waist, hip, body protein, body fat, abdominal fat, total cholesterol, HDL-cholesterol, triglyceride, total protein, albumin, hemoglobin, hematocrit, fasting blood glucose, ferritin, IL-2, IL-6, TNF-${\alpha}$, CRP, TAS, TBARS, systolic blood pressure, and diastolic blood pressure. The subjects were divided into three groups based on age (65-74y, 75-84y, 85y${\leq}$) and were divided into two groups according to the sum of the Nutrition Screening Initiative (NSI) checklist score (adequate nutritional status, NSI score ${\leq}$3; at risk of malnutrition, NSI score >3). Mean and frequency of variables were estimated. Analysis of Variance, Tukey test, Chi-square test, and Multiple linear regression analyses were performed. Mean BMI and body fat were 25.1 $kg/m^2$ and 40.0%, respectively. However, for over 80% of subjects, the intakes of energy, fiber, thiamin, riboflavin, niacin, folate, Ca, K, and Zn were less than the Korean DRI (EAR or AI). The subjects who had lower NSI score tended to have better health status, eat meals frequently, have less depression, and exercise regularly. The subjects who had higher NSI score tended to have tooth problems, to eat alone most of time, and to be physically unable to cook or feed. Serum IL-6 and TNF-${\alpha}$ were significantly related with nutritional status which suggested higher tendency of inflammatory response. Serum IL-2, TAS, and glucose were significantly correlated with body fat (%) or abdominal fat (%). These results suggest that improving the nutritional status, increasing regular exercise, maintaining normal weight are beneficial to health care of low income elderly women.

An Analysis on Factors Affecting Local Control and Survival in Nasopharvngeal Carcinoma (비인두암의 국소 종양 치유와 생존율에 관한 예후 인자 분석)

  • Chung Woong-Ki;Cho Jae-Shik;Park Seung Jin;Lee Jae-Hong;Ahn Sung Ja;Nam Taek Keun;Choi Chan;Noh Young Hee;Nah Byung Sik
    • Radiation Oncology Journal
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    • v.17 no.2
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    • pp.91-99
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    • 1999
  • Propose : This study was performed to find out the prognostic factors affecting local control, survival and disease free survival rate in nasopharyngeal carcinomas treated with chemotherapy and radiation therapy. Materials and Methods : We analysed 47 patients of nasopharyngeal carcinomas, histologically confirmed and treated at Chonnam University Hospital between July 1986 and June 1996, retrospectively. Range of patients' age were from 16 to 80 years (median; 52 years). Thirty three (70$\%$) patients was male. Histological types were composed of 3 (6$\%$) keratinizing, 30 (64$\%$) nonkeratinizing squamous cell carcinoma and 13 (28$\%$) undifferentiated carcinoma. Histoiogicai type was not known in 1 patient (2$\%$). We restaged according to the staging system of 1997 American Joint Committee on Cancer Forty seven patients were recorded as follows: 71: 11 (23$\%$), T2a; 6 (13$\%$), T2b; 9 (19$\%$), 73; 7 (15$\%$), 74: 14 (30$\%$), and NO; 7 (15$\%$), Nl: 14 (30$\%$), N2; 21 (45%), N3: 5 (10%). Clinical staging was grouped as follows: Stage 1; 2 (4$\%$), IIA: 2 (4$\%$), IIB; 10 (21$\%$), III; 14 (30$\%$), IVA; 14 (30$\%$) and IVB; 5 (11$\%$). Radiation therapy was done using 6 MV and 10 MV X- ray of linear accelerator. Electron beam was used for the Iymph nodes of posterior neck after 4500 cGy. The range of total radiation dose delivered to the primary tumor was from 6120 to 7920 cGy (median; 7020 cGy). Neoadjuvant chemotherapy was performed with cisplatin +5-fluorouracil (25 patients) or cisplatin+pepleomycin (17 patients) with one to three cycles. Five patients did not received chemotherapy. Local control rate, survival and disease free suwival rate were calculated by Kaplan-Meier method. Generalized Wilcoxon test was used to evaluate the difference of survival rates between groups. multivariate analysis using Cox proportional hazard model was done for finding prognostic factors. Results: Local control rate was 81$\%$ in 5 year. Five year survival rate was 60$\%$ (median survival; 100 months). We included age, sex, cranial nerve deflicit, histologic type, stage group, chemotherapy, elapsed days between chemotherapy and radiotherapy, total radiation dose, period of radiotherapy as potential prognostic factors in multivariate analysis. As a result, cranial none deficit (P=0.004) had statistical significance in local control rate. Stage group and total radiation dose were significant prognostic factors in survival (P=0.000, P=0.012), and in disease free survival rates (P=0.003, P=0.008), respectively. Common complications were xerostomia, tooth and ear problems. Hypothyroidism was developed in 2 patients. Conclusion : In our study, cranial none deficit was a significant prognostic factor in local control rate, and stage group and total radiation dose were significant factors in both survival and disease free survival of nasopharyngeal carcinoma. We have concluded that chemotherapy and radiotherapy used in our patients were effective without any serious complication.

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Young Rabbit Model for Pathophysiologic Study of Acute Lung Injury in Early Childhood (유아기 급성폐손상 병태생리 연구를 위한 어린 토끼 실험모델)

  • 권영민;최석철;박종원;김양원;이양행;황윤호;조광현
    • Journal of Chest Surgery
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    • v.36 no.8
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    • pp.545-558
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    • 2003
  • Adult respiratory distress syndrome (ARDS) is of particular interest because of its severity of the associated lung injury and its high mortality. However, the pathophysiologies of ARDS in infant and childhood groups are still not well clarified inspite of many previous investigations. To investigate the time course of pathophysiology of ARDS in infant and childhood groups, this study was designed with experimental endotoxin-induced ARDS model using young rabbits (8 week-old). Material and Method: Rabbits were divided into the control group (n=8) and the endotoxin-treated group (n=32). The endotoxin group was subdivided into 4 groups by the sampling times as 3, 6, 12 and 24 hr-groups (G- $E_{3,6,12,24,}$ each n=8). The experimental ARDS was made by a bolus injection of endotoxin (Escherichia coli serotype 055 : B5, 0.50 mg/kg) via rabbit ear vein. For evaluation of the hematologic and inflammatory markers, and superoxide dismutase (SOD) concentrations, the blood samples were taken from the heart. The bronchoalveolar lavage fluid (BALF) were obtained for analysis of the leukocytes and protein concentration. With biopsy of the lung, histopathologic changes of the lung were also evaluated. Result: In the endotoxin groups, significant leukopenia (owing to pancytopenia) occurred in 3 and 6-hr groups, which was followed by significant leukocytosis (owing to neutrophilia) in the 12 and 24-hr groups (p<0.05). Serum levels of tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin-1 $\beta$ (IL-1 $\beta$) in the endotoxin groups were higher than those of control group (p<0.05). Serum levels of superoxide dismutase (SOD) of G- $E_{3}$ and G- $E_{6}$ were higher than those of control group, whereas those of G- $E_{12}$ were lower than those of control groups (p<0.05). Total leukocyte counts and protein con-centrations in BALF were significantly elevated in the endotoxin groups compared to the control group (p < 0.05). The hemorrhagic pattern of BALF showed occurred in the endotoxin groups. The endotoxin groups (in G- $E_{6}$) had severe infiltration of inflammatory cells (lymphocyte and monocyte) in the pulmonary interstitium and parenchyma, migrations of neutrophil and eosinophil into alveolar spaces and interstitial widening, which are the evidences of acute lung injury. In the endotoxin groups, there were significant positive correlations between the BALF findings and the immunologic markers (TNF-$\alpha$, IL-1$\beta$, SOD) (p<0.05). Conclusion: Severe acute lung injury occurred in all the endotoxin-treated rabbits. The pathophysiologic findings were so progressive until 6-hr by time dependant pattern, and then recovered slowly, Variable hematologic, immuno-logic, and pathologic factors were well correlated in the development and progression of endoxin-induced lung injury. The pathophysiologic responses were sensitive and rapid in young rabbit Young rabbit seemed to be a useful experimental animal model for infant and childhood groups.roups.

The Studies on Growth Characteristics and Dry Matter Yield of Hybrid Corn Varieties in Daegwallyeong Region (대관령에서 옥수수 품종별 생육특성과 건물수량에 기후변화의 영향)

  • Kim, Meing Jooung;Seo, Sung;Choi, Ki Choon;Kim, Jong Geun;Lee, Sang Hack;Jung, Jeong Sung;Yoon, Sei Hyung;Ji, Hee Chung;Kim, Myeong Hwa
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.33 no.2
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    • pp.123-130
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    • 2013
  • This study was conducted to investigate the effects of climate change on the growth characteristics and dry matter yields of silage corn hybrids in fields of forage crops of Hanwoo Experiment Station, National Institute of Animal Science, RDA, from Apr. 2009 to Sep. 2011. Corn hybrids were cultivated in Daegwallyeong of Gangwon Province, at an altitude of 760 m. Corn varieties used in this study consisted of 5 domestic varieties and 5 foreign varieties. Differences of silk days according to years occurred at an average of 5.5 days. The silk periods of domestic varieties occurred from Aug. 8 to 12, while that of overseas varieties was from Aug. 5 to 11. Silk days of domestic varieties occurred approximately 3 to 4 days earlier than those of oversea varieties. Silk days of Kwangpyeongok and P3156 belonging to the early varieties were Aug. 8 and 5, respectively. Kwangpyeongok and P3156 were Aug. 8 and 5, respectively. Pyeonganok and DK729 belonged to late varieties. The mean plant height of corn was approximately 231 cm, while those of Kwangpyeongok and Pyeonganok were 236 cm and 237 cm, respectively. The mean stem diameter and ear height of corn were approximately 23.2 mm and 94 cm, respectively. In the case of stem diameters, those of Cheonganok and 33J56 were 86 cm and 80 cm, respectively, while Gangdaok grew to a greater height (enter height) than other varieties. Dry matter yields of Kwangpyeongok and Pyeonganok were higher than those of other varieties. The mean leaf ratio of corn was 39.3%, while that of domestic varieties increased as compared to foreign varieties. The average DM yield of corn was 16,653 kg/ha, while those of 32P75, P3156, Pyeonganok, P3394 and Kwangpyeongok were 18,901, 17,997, 17,675, 17,194, 17,188 kg/ha, respectively. Total digestible nutrient (TDN) yields of 32P75, P3156, P3394, Pyeonganok and Kwangpyeongok were 13,381, 12,590, 12,532, 12,140 and 12,036 kg/ha, respectively. Corn crude protein (CP), in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF), acid detergent fiber (ADF) and TDN were 7.8%, 74.2%, 42.4%, 23.5% and 70.3%, respectively. In the case of nutritive values of corn, there was no significant difference between of corn varieties of domestic and foreign origin.

Mechanical and Operational Factors Affecting the Efficiency of Rice Polishing Machines (정미기의 능률에 미치는 기계적 요인및 작동조건에 관한 연구)

  • No, Sang-Ha
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.15-15
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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?iency 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?ween 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?ease 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?ses 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?ear 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?ber 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?very rates. The higher the rate of increase, the lower were the resulting head rice recoveries.