• Title/Summary/Keyword: Compensatory growth.

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THE COMPARATIVE STUDY OF THE EFFECT OF THE SEMI RIGID AND RIGID FIXATIONS OF THE GROWTH OF THE CRANIOFACIAL SKELETON (반강성(半剛性) 및 강성고정(剛性固定)이 두개안면골(頭蓋顔面骨)의 성장(成長)에 미치는 영향(影響)에 관한 연구(硏究))

  • Lee, Sang-Chull;Kim, Yeo-Gab
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.15 no.3
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    • pp.157-170
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    • 1993
  • To prove the effct of semi-rigid fixation which utilize wire and rigid fixation which utilizes miniplate toward cranio-facial growth and development of growing children for teenagers, 28 rabbits-6 weeks, about 1.5kg-were experimented. They were classified three groups the semi-rigid group was 12 rabbits which were fixed with 26 gauge stainless steel wire to cross a fronto-nasal suture, the rigid group was the other 12 rabbits which were fixed with miniplate and screw, the control group was 4 rabbits which were get rid of only periosteum. The sample of fronto-nasal of rabbits which were sacrified after 2 weeks, 4 weeks, 8 weeks, and 12 weeks of the operation were investigated and made a comparative study with the light microscops. 1. At the control group, the central part of bony suture was connected with colagen bundle, the osteoblastic layer was investigated at the bony ending, new bone which covered the inside and outside faces of the bone suture was formed between periosteum. 2. Two weeks later from the experiment, ran slightly irregularly the collagen bundle which connects both bony endings of the rigid group. 3. Four weeks later from the experiment, collagen bundle of bone surface were arranged parally a little and comparing to the semi-rigid group, newly formed woven bone of surface of the adjacent bone was made obviously a little. 4. Eight weeks later from the experiment, collagen bundle which is located between both bony ending become close. Both the semi-rigid group and the rigid group showed significant formation of new bone at the periosteum and the bone surface. 12 weeks later from the experiment, both the semi-rigid group and the rigid group showed the regular running in the collagen bundle and smooth, dense periosteum. Then they assumed a similar aspect of the control group. I think that it does not give the influence to the cranio-facial growth of children or teenager to utilize a rigid fixation for a short period. Because as the time goes on, the surface of the bone suture was recovered and adjacent bone surface of the miniplate fixation showed compensatory growth, although both the semi-rigid group which utilized wire and rigid group which utilized a miniplate brought about the change of the area of the bone suture at the early period.

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Growth, Photosynthesis and Rubisco Activity of Resistant Hybrid Poplar(Populus trichocarpa×P. deltoides) to Ozone Exposure: A Link with Compensatory Strategy (오존에 노출(露出)시켰을 때 저항성(抵抗性)을 갖는 잡종(雜種)포플러의 생장(生長), 광합성(光合成) 그리고 Rubisco 활성(活性)에 관(關)한 연구(硏究): 수목(樹木)의 보상전략(補償戰略)과의 관계(關係))

  • Woo, Su-Young
    • Journal of Korean Society of Forest Science
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    • v.86 no.1
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    • pp.80-86
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    • 1997
  • The objective of this study was to investigate how resistant poplar hybrid makes compensation to ozone stress. Growth, net assimilation rate and initial Rubisco activity were investigated. This study elucidates the physiological mechanisms associated with ozone sensitivity and resistance in 3 selected $F_2$ hybrids, a family originating from a cross between Populus trichocarpa${\times}$P. deltoides. Open-top chambers were used. Ozone concentrations varied from 90 to 115 ppb for 126 days, 6 to 9 hours in a day. This study tested the hypothesis that resistant poplar hybrid maintains the biomass production to ozone exposure via increased net assimilation rate and Rubisco activity. Growth, biomass, net assimilation rate and initial Rubisco activity were generally reduced by ozone treatment. In the tree parts, root under ozone stress was the most sensitive part. Reduced allocation of photosynthates to root growth might be due to increased respiratory demands for maintenance and repair of aboveground tissue damaged by ozone stress. Maintenance or increases remaining leaves in photosynthetic rates and Rubisco activity in resistant clone in response to ozone treatment were the results of biological compensation to ozone stress.

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Effects of the plane of nutrition for grower pigs on their grow-finish performance and meat quality in winter

  • Yang, Bo-Seok;Kim, Myeong Hyeon;Choi, Jung-Seok;Jin, Sang Keun;Park, Man-Jong;Song, Young-Min;Lee, Chul Young
    • Journal of Animal Science and Technology
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    • v.61 no.1
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    • pp.1-9
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    • 2019
  • Little is known about the effects of the plane of nutrition on growth performance and meat quality of grow-finish pigs under commercial production conditions. The present study was thus addressed to this virtually unanswered question. One hundred and two barrows and 102 gilts weighing approximately 24 kg were fed phase I and II grower diets with a high, medium, or low plane of nutrition (HP, MP, or LP) to approximately 43 and 70 kg, respectively, in 6 replicates (pens). Subsequently, the HP and MP groups were fed the HP and MP1 finisher diets, respectively, the LP group being fed a second MP (MP2) finisher diet (LP1 group). Moreover, 68 LP-grower-fed barrows and gilts were added to the feeding trial and fed the MP1 and LP finisher diets to approximately 95 kg and thereafter, respectively (LP2 group). All MP diets had the lysine:calorie ratios comparable to the RNC recommendations, with < 18% differences between those of the HP and LP diets. The finisher pigs were reared in 16 pens and slaughtered at approximately 115 kg. The gain:feed ratio, but not average daily gain (ADG), was greater for the HP group than for the MP and LP during the grower phase I whereas during the grower phase II, ADG was greater (p < 0.05) for the HP and LP groups vs. MP. During the finisher phase I, ADG was less for the LP (LP1 + LP2) group vs. HP and MP, with no difference between the HP and MP groups; the gain:feed ratio was less for the LP vs. MP group. Backfat thickness was greater for the LP vs. HP group. The water holding capacity of fresh longissimus dorsi muscle (LM) and the sensory juiciness score for cooked LM were greatest for the LP group, the sensory flavor and tenderness scores being greater for the LP group vs. MP. In conclusion, results suggest that compensatory growth occurred for the LP and MP groups during the grower phase II and finisher phase I, respectively, with fat deposition increased for the LP group and that meat quality could be improved by the use of LP.

Effect of Caecectomy on Body Weight Gain, Intestinal Characteristics and Enteric Gas Production in Goslings

  • Chen, Yieng-How;Wang, Shu-Yin;Hsu, Jenn-Chung
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1030-1034
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    • 2003
  • Two experiments of four-week duration were conducted to investigate the effect of caecectomy on the intestinal characteristics, body weight gain and gas production in the caeca of White Roman goslings. In experiment I, forty eight 2-wk-old female goslings with similar body weight were randomly divided into four treatments: sham (SHAM), left side caecum removed (LSCR), right side caecum removed (RSCR) and both caeca removed (CAECECTOMY). Smimilarly, experiment II was conducted with twelve 5-wkold male goslings in two treatments: SHAM and CAECECTOMY. Free choice water with ad libitum feed was provided during experiment. At the end of experiment I, goslings were sacrificed and gut length and weight were determined. At 7 and 9 wks of age, birds in experiment II were subjected to respiration calorimetry studies. In both experiments, final body weights were not affected by caecectomy. Results of experiment I indicated that caecectomy did not significantly affect the relative weight (g/100 g BW) of gizzard, small intestine, rectum and colon (p>0.05); however, the relative length of colon and rectum did increase (p<0.05). The remaining caecum did not show compensatory growth in both LSCR and RSCR treatments. In experiment II, results indicated that the average enteric methane production from the caecetomised goslings was significantly lower than that from the bird in SHAM goslings (p<0.05). In comparison with SHAM goslings, calorific loss from entric methane in caecetomised birds was lower (p<0.05). There was no effect of age on methane production. The enteric nitrous oxide production in caeca of goslings was very low with no significantly different between two treatments.

Physiological and Histological Characteristics of Starry Flounder Platichthys stellatus after Starvation and Re-feeding (절식 후 먹이 재 공급시 강도다리P(latichthys stellatus)의 생리·조직학적 특성)

  • Kim, Su Kyoung;Shim, Na Young;Jang, In Kwon;Lee, Chu;Kim, Yong Dae;Kim, Bung Ki;Kim, Jae Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.793-800
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    • 2013
  • This study was conducted to determine the physiological and histological characteristics of starry flounder Platichthys stellatus juveniles to undergo a short/long starvation period and subsequent re-feeding with 2 weeks interval for 65 days. All findings from this study indicate the possibility of a very rapid recovery possibility of starry flounder after short starvation period for 2 or 4 weeks. The mean body weight after 2 and 4 weeks starvation were not significantly different after 65 days. However, the body weight of 6 and 8 weeks starved fishes showed significantly low value than 2 weeks starved fishes. All biomarkers, liver somatic index, RNA/DNA ratio and blood chemistry, in this study showed fast recovery possibility after re-feeding of starry flounder. During the starvation and recovery process, they showed distinct increasing and decreasing tendency. From 21-28 days after re-feeding, most biomarkers reached to their maximum value and thereafter decreased again in 2, 4 and 6 weeks starvation and re-feeding groups. It could be interpreted as a compensatory growth and strategical action against starvation.

Correction of Transverse Discrepancy with Slowly Maxillary Expansion by Hyrax type expander in Adult Patient (성인에서 Hyrax 장치로 완속상악확장하여 폭경부조화를 개선한 증례)

  • Kwak, Kyoung Ho;Kim, Seong Sik;Kim, Yong-Il;Park, Soo-Byung;Son, Woo-Sung
    • The Journal of the Korean dental association
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    • v.55 no.6
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    • pp.400-410
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    • 2017
  • Approximately 30% of adult patients who want orthodontic treatment have transverse discrepancy with insufficient width of the maxilla. Particularly, in Class III patients requiring orthognathic surgery, the frequency of insufficient width of the maxillary arch related to respiratory problems is high. We report a case of non-surgical maxillary expansion using a Hyrax type expander with an orthognathic surgery, based on the reports that the ratio of non-fused midpalatal suture is not high in adults. A 30 years and 2 months old woman with a long face showed an Angle Class III with a vertical growth pattern. Class III molar and canine relation, anterior edge bite, and mandibular incisor compensatory lingual inclination were observed. The posterior buccal overjet seemed to be appropriate, but I diagnosed that there was a transverse discrepancy, for the following reasons. The inter-canine and inter-molar widths were sufficient but excessive lingual inclination of the mandibular molars was observed when assessing the bucco-lingual inclination based on the center of resistance of the maxillary and mandibular first molar. For this reason, it was expected that intercuspal interference would occur during orthodontic decompensation. Therefore, slow maxillary expansion using Hyrax type expander was performed and 2-jaw rotation surgery was performed to improve aesthetic and occlusion. Adults can also improve width discrepancy by non-surgical methods, which can avoid SARPE requiring additional surgery or segmental surgery lacking stability and predictability.

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Exploring Factors of Corporate Entrepreneurship within Medical Institutions : Focusing on the Perspective of Participants in the In-house Innovation & Start-up Contest (의료기관 내 사내기업가정신 확산 요인에 대한 탐색 : 사내 혁신·창업 공모전 참가자의 관점에서)

  • Jae-hoon, Han;Byeung-tae, Park;Byung-jin, Park
    • Korea Journal of Hospital Management
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    • v.27 no.4
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    • pp.36-55
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    • 2022
  • Purpose: This study explores the diffusion factors of corporate entrepreneurship among members of medical institutions. Methodology/Approach: The study explores the case of Granum Sinapis Center at Seoul St. Mary's Hospital, the first medical institution to establish a support organization for "innovation and start-up" as well as examines the changes in individual perceptions of participants in the institution's in-house contest. Among the 140 participants in the 2nd Contest held in 2022, seven participants were selected for interview in consideration of their job occupation and years of service. In-depth interviews were conducted for each individual. Findings: The participants applied for the contest under the direct and indirect influence of co-workers as well as compensatory factors. An individual's corporate entrepreneurial characteristics can be innate or acquired. The participants of the in-house contest had a positive experience in contrast to the existing organizational culture. The results reveal that emotional support from top and middle managers, along with the role of dedicated departments, can affect innovative behavior. Practical Implications: Contest participants reported personal growth, improved job satisfaction, and a change in perception of the organizational culture; they expressed their willingness to recommend. The results confirm the need to support such systems and shift focus to managerial (emotional) support and dedicated resources for developing individual entrepreneurship.

A STUDY ON THE CHANGE OF AIRWAY SPACE AND CRANIAL, CERVICAL ANGULATION AFTER MANDIBULAR SETBACK OPERATION (하악골 후방이동 수술후 기도 공간과 두개 및 경추 각도의 변화에 관한 연구)

  • Chang, Hyun-Ho;Kim, Jae-Seung;Yi, Choong-Kook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.2
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    • pp.115-131
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    • 2000
  • In the study of craniofacial deformity, it is very important that identifying the factor which can affect the morphology and which is closely related to the morphology, because it can not only improve the comprehension of growth and developmental process but also be applied in growth prediction and treatment modality. Several investigators have already mentioned the characterstics of head posture and airway space in relations to morphologic difference. But it is very meaningful work in clarifying the correlation between morphology, head posture and airway space that observing the change of head posture after morplologic change caused by operation and the change of airway space after same procedure. To investigate above correlation, I selected normal group which is consisted of 43 adults and mandibular prognathism group which is consisted of 47 adults who had been operated by sagittal split ramus osteotomy and were followed up more than 1 year. With their lateral skull radiograghs, reference lines which can evaluate each measuring points and areas without effect of postural change were first determined. And using above reference lines, change of airway space, positional change of tongue and hyoid, change of cranial and cervical angulations were measured. The results obtained from the study were as follows 1. In the change of head posture, the position of tongue and hyoid neighboring to pharynx is more closely related to the reference line of cervical column than to reference line of cranium. 2. After mandibular setback operation, the airway dimension was decreased to 81.6% of preoperative state at 1 month postoperatively and was slightly increased to 89.7% at 1 year postoperatively. 3. Posterior movement of tongue plays important role in decrease of airway dimension and inferior movement of hyoid was closely correlated with posterior movement of tongue. 4. Postoperative anterior movement of mandible, namely, morphologic relapse had correlation with relapse phenomenon of airway dimension. 5. Craniocervical angulation increased postoperatively. Especially in the postoperative early state, there was increased foreward inclination of cervical angulation rather than increase of cranial angulation. But at postoperative 1 year it was observed that cervical inclination was returned to preoperative state and cranial angulation was increased gradually. 6. Increase rate of airway dimension was correlated with the increase of cranial angulation from postoperative 1 month to 1 year. In conclusion, relapse tendency of airway dimension following increase of cranial angulation was found after mandibular setback operation and it is considered that increase of cranial angulation is one of compensatory mechanism in airway maintenance.

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EXPERIMENTAL STUDY ON RELAPSE AFTER RAMAL LENGTHENING IN DIFFERENT SURGICAL METHODS - RADIOGRAPHIC EVALUATION (하악지 길이증가를 위한 수술방법들간의 회귀현상에 관한 실험적 연구)

  • Yi, Choong-Kook;Chang, Hyun-Ho;Park, Jung-Hyun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.6
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    • pp.636-643
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    • 2000
  • Facial asymmetry is the most frequent disease in craniofacial deformities. And the primary causing area of that is mostly placing in mandible. That is to say, it is known that primarily, mandible grows excessively or deficiently, and other facial region involving maxilla undergoes compensatory growth secondarily, so asymmetric face develops. In facial asymmetry, the surgical correction of undergrowth is more difficult than that of overgrowth and the reason of it is the postoperative relapse caused by stress of surrounding soft tissues. It means the stress of surrounding soft tissues occurring after bone lengthening and reducing above stress is the same meaning with reducing postoperative relapse. Among various areas, mandibular ramus is the most difficult area to lengthen vertically and maintain its length. The reason of it is considered by many authors as the stress of surrounding pterygomasseteric sling which is enveloping lower border of mandible and interrupting elongation of ramal height. So we applied two different surgical procedures in which pterygomasseteric slings have different stress respectively to monkeys which have similar masticatory function and anatomy to human being and compared relapse by radiographic film and observed periodically the histochemical change of masseteric muscle fiber. So we could see the following results. The relapse was less in EVRO group in which we separated pterygomasseric sling in inferior border and didn't approximate muscle sling after vertical lengthening to minimize the stress of soft tissues than IVRO group in which we elongated ramal height preserving pterygomassetric sling. Of course, we could see a problem in EVRO group such as bone resorption in inferior border caused by uncovering the periosteum of inferior border. But we expect that such problem will be solved by developing periosteum substitutes for covering the exposed bone and minimizing the surgical trauma. In histochemical study of masseteric muscle fiber, the fiber constituents of EVRO group in which we minimized soft tissue stress was changed immediately after operation and maintained it for 1 year, whereas that of IVRO group in which we preserved soft tissue stress was changed in more portion after operation and recovered it by 1 year. By the histochemical results, we can see that the recovery of fiber constituents reflect the recovery of muscle stress and it is closely related with relapse phenomenon.

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Studies on Economic Damage of Korean Rice Pests (벼해충의 경제적 피해에 관한 연구)

  • Catling H. D.;Lee S. C.
    • Korean journal of applied entomology
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    • v.16 no.2 s.31
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    • pp.79-86
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    • 1977
  • Four experiments were carried out under farmer's field conditions to determine economic threshold levels of major rice pests aad attempt a reduction in the number of insecticide applications. In the experiments were included check treatments, insecticide schedules representing the official recommendations to farmers, and several corrective treatments. A careful record was kept of insect pest densities and disease incidence. i) In the north at Suweon and Icheon where Chilo suppresalis. (Walk.), the striped rice borer, was active in the first generation, no significant yield differences were obtained between plots receiving several insecticide applications and those left totally unprotected. The mean yields were high (5.2-7.6t/ha). ii) First generation borer activity rising to $8.6\%$ injured tillers was below the economic threshold since no yield reduction was recorded in either japonica varieties or the high-yielding Tongil variety. iii) Evidence was obtained thst berer damage was made good by replacement of infested tillers (compensatory growth), C. suppressalis populations were always low in the second generation. iv) The experimental results obtained at Suweon and Icheon do not justify the present official recommendations of 6-7 pesticide applications. v) further south at Iri a substantial yield reduction occurred due to an early outbreak of stripe disease transmitted by Laodelphax striatellus (Fallen), the small brown planthopper; a mean of 1-2 individuals/hill was recorded immediately after transplanting. C. suppressalis probably contributed to this yield reduction. vi) Several applications against the vector failed to prevent the rapid spread of stripe to the susceptible variety in the Iri experiment: in surrounding fields the resistant Tonsil varivety was ralatively unaffected. vii) Pests of lesser importance were Nephotettix cinctieps (Uhler), Nilaparvata lugens (Stil), Sogatella furcifera (Horv..), and leaf miners.

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