• Title/Summary/Keyword: tapering ratio

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Experience with Tapering Enteroplasty in Intestinal Atresia (선천성 장무공증 환아에서 Tapering Enteroplasty 경험)

  • Chung, Jae-Hee;Kim, Soo-Hong;Song, Young-Tack
    • Advances in pediatric surgery
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    • v.13 no.1
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    • pp.23-29
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    • 2007
  • Tapering enteroplasty was first described by Thomas in 1969 as one method of intestinal anastomosis. The advantages of tapering enteroplasty in the intestinal atresia are: First, it makes end-to-end anastomosis possible between the atretic bowel ends with considerable differences in diameters. Second, it promotes the recover of the postoperative bowel function. Third, it prevents the possibility of the short bowel syndrome by eliminating the need of resecting the dilated bowel. A total of 22 patients with intestinal atresia who underwent tapering enteroplasty from January 1988 to December 2005 at our institute were reviewed. In 3 of 22 cases, tapering enteroplasty was the $2^{nd}$ operation after an initial end-to-oblique anastomosis. We reviewed the following items: age, sex, type and location of intestinal atresia, initial feeding and total enteral feeding start day, the length of hospital stay and complications. The average age of the patients was 7 days. Male to female ratio was 1 to 1.2 (10 cases: 12 cases). We performed the tapering enteroplasty on all types and locations of the intestinal atresia from the duodenum to the colon: type I (n=3), type II (n=4), type IIIA (n=7), type IIIB (n=5), type IIIB and IV (n=1), type IV (n=1) and type C (duodenum) and type IIIB and IV (jejunum). On the average, the oral feeds were started on the postoperative $8.8^{th}$ day, and full caloric intake via the enteric route was achieved on postoperative $13.3^{th}$ day. The average length of hospital stay was 19.6 days. There were 1 case (4.5 %) of anastomotic complication and 2 cases (9 %) of adhesive ileus among 22 patients. The tapering enteroplasty on all types of intestinal atresia is a usefull operative method when there are considerable diameter differences between the atretic bowel ends.

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A COMPARISON OF THE FORM OF THE FACE, THE DENTAL ARCH AND THE MAXILLARY CENTRAL INCISOR (안모, 치열궁 및 상악 중절치의 형태에 관한 상호 비교 연구)

  • Lee Bong-Ho;Chung Chae-Heon
    • The Journal of Korean Academy of Prosthodontics
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    • v.30 no.2
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    • pp.273-285
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    • 1992
  • The purpose of this study was to evaluate facial form, arch form and tooth form in young adults to determine if a correlation exists. 115 subjects who had healthy natural maxillary incisors and good occlusion consisted of 71 males and 44 females ranging from 20-30 years of age. Facial photographs and, intraoral photographs of upper anterior teeth and dental casts of upper jaws were taken to demonstrate facial form, dental arch form and tooth form. Form analysis is determined by comparing the ratio of the widths of the faces, dental archs and the teeth. The Chi-square test of independence between facial form, arch form and tooth form, was executed and the significance level determined. The results were as follows : 1. The distribution of facial forms was 66.1% square-tapering, 27.0% square, 5.2% ovoid, 2% tapering-square. 2. The distribution of tooth forms was 65.2% ovoid, 20.0% square-tapering, 11.3 % tapering-square, 3.5 % square. 3. The distribution of arch forms was 50.4 % square-tapering, 48.7 % tapering, 0.9 % reverse tapering-square. 4. There was no large differences in the distribution of facial forms, dental arch forms and tooth-forms between male and female. 5. No relationship existed between the tooth form and the facial form. 6. No relationship existed between the facial form and the dental arch form. 7. No relationship existed between the tooth form and the dental arch form. 8. This gave the impression that dental arch form and facial form could not be used as a true index in tooth selection.

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Clinical Experience of Tapering Enteroplasty Using GIA Stapler in Jejunoileal Atresias (소장 무공증 환아에서 GIA stapler를 이용한 Tapering Enteroplasty 임상경험)

  • Song, Young-Tack
    • Advances in pediatric surgery
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    • v.1 no.1
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    • pp.27-32
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    • 1995
  • Jejunal and ileal atresias are the most common cause of congenital intestinal obstruction and accounts for about 1/3 of all cases of intestinal obstruction in newborns. Despite the relative frequency of this anomaly, its survival rate was less than 10% up to 1950, more recently the survival rate has risen rapidly to 90% with the introduction of modern surgical techniques and the use of total parenteral nutrition. In 1969 Thomas described a tapering jejunoplasty to manage the discrepancy in the size of the proximal dilated lumen & contracted distal lumen, and to preserve absorptive surface when the dilated jejunum involved a long length, and Grosfeld et al.(1979) facilitated this method by using GIA staplers. Author have also used GIA stapler to resect the antimesenteric portion of the dilated proximal bowel in 8 cases of jejunoileal atresias with good results. The following results were obtained ; 1. There we 3 jejunal atresias & 5 ileal atresias, and male to female sex ratio was 5 : 3. 2. The type of atresia was as follows ; type IIIa was 3 cases, type IIIb was 4 cases, type IIIb+IV was 1 case. 3. In non-complication cases(5 cases), the mean hospital day was 16 days, and oral feeding was feasible from 6.2 days after operation. 4. The complications(anastomotic leakage, pneumonia) were frequently occurred in type IIIb cases and in low birth weight cases(75%). 5. Mortality rate was 25% including DAMA(discharge against medical advice) discharge case.

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Comparative Study on the Structure of Vascular Cambium in Some Salicaceae (수종의 버드나무과 유관속 형성층의 구조에 관한 비교연구)

    • Korean Journal of Plant Resources
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    • v.11 no.3
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    • pp.326-334
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    • 1998
  • Vascular cambium in 16 species of Salicaceae is nonstoried in all of them and is made up of fusiform and ray initials. The growth of cambial girth occurred by pseudotransverse division of fusiform initials and subsequent apical intrusive growth of daughter initials. The measurements of fusiform initials in tangerntial sections have revealed that the average length varies from 252.2-437.1${\mu}{\textrm}{m}$ in investigated species, with the maximum being in Populus euramericana and the minimum in Salix purprea var. Multinervis. The length of fusiform initials depends on the length of the tapering end wall , therefore, the longer the length of the tapering end wall, therefore, the longer the length of the taperding end wall, the longer the length of fusiform initials. Ray initials have their own size, magnitude, and frequency of occrrence in each species. The relative proportion of ray initials fall about 15.0-24.5% in Salicaceae. Shrubby species of Salix have a lower ratio of ray initials than the species which possess wider trunks. New ray initials are originated from cut off the side or the end of fusiform initials and central partition of a fusiform initials.

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Shear strength of non-prismatic steel fiber reinforced concrete beams without stirrups

  • Qissab, Musab Aied;Salman, Mohammed Munqith
    • Structural Engineering and Mechanics
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    • v.67 no.4
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    • pp.347-358
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    • 2018
  • The main aim of this research was to investigate the shear strength of non-prismatic steel fiber reinforced concrete beams under monotonic loading considering different parameters. Experimental program included tests on fifteen non-prismatic reinforced concrete beams divided into three groups. For the first and the second groups, different parameters were taken into consideration which are: steel fibers content, shear span to minimum depth ratio ($a/d_{min}$) and tapering angle (${\alpha}$). The third group was designed mainly to optimize the geometry of the non-prismatic concrete beams with the same concrete volume while the steel fiber ratio and the shear span were left constant in this group. The presence of steel fibers in concrete led to an increase in the load-carrying capacity in a range of 10.25%-103%. Also, the energy absorption capacity was increased due to the addition of steel fibers in a range of 18.17%-993.18% and the failure mode was changed from brittle to ductile. Tapering angle had a clear effect on the shear strength of test specimens. The increase in tapering angle from ($7^{\circ}$) to ($12^{\circ}$) caused an increase in the ultimate shear capacity for the test specimens. The maximum increase in ultimate load was 45.49%. The addition of steel fibers had a significant impact on the post-cracking behavior of the test specimens. Empirical equation for shear strength prediction at cracking limit state was proposed. The predicted cracking shear strength was in good agreement with the experimental findings.

A STUDY ON THE MECHANICAL BEHAVIORS OF ABUTMENT TEETH AND SUPPORTING TISSUE OF THE TELESCOPE DENTURE BY THE FINITE ELEMENT METHOD (유한요소법(有限要素法)에 의(依)한 Telescope Denture의 지대치(支臺齒) 및 지지조직(支持組織)의 역학적(力學的) 반응(反應)에 관(關)한 연구(硏究))

  • Kim, Moon-Ki;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.22 no.1
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    • pp.109-122
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    • 1984
  • The purpose of this study was to analyze the magnitude and mode of the stress distribution induced in the supporting alveolar bone and periodontal ligament and, to determine the displacement of abutment teeth and telescope denture base by applying chewing force to the telescope denture quantitatively and qualitatively. Two finite element models of telescope denture that were restored the missing mandibular second molar with two abutment teeth which were constructed. In two different models, parallel and tapering type telescope crowns were constructed. These finite element models of two cases used for these experiment were a two-dimensional mesiodistal section of the mandibular second bicuspid and first molar. Chewing force of 25Kg that was devided in the ratio of 45/155 (29%) in bicuspid and 55/155 (35.5%) in molars was applied to telescope denture and abutment teeth respectively. The displacement of the telescope denture base and abutment teeth and the stress distribution in the periodontal ligament and alveolar bone were analized to investigate the influence of chewing force acting on the telescope denture and abutment teeth. The results were as follows: 1. Abutment teeth displaced mesially and the magnitude of displacement of abutment teeth in vertical direction were more than that of horizontal direction in two cases. The displacement of abutment teeth on the telescope denture treated with tapering type telescope crown were less than that of the parallel type crown. 2. The displacement of the telescope denture base that were treated with parallel type telescope crown were less than that of treated with tapering type telescope crown. 3. The stress induced in the alveolar bone and periodontal ligament on abutment teeth that treated with parallel type telescope crown were more than that of treated with tapering type telescope crown and more stress induced in the alveolar bone than in the periodontal ligament. 4. In the telescope denture, the magnitude of displacement of abutment teeth and stress induced in the periodontal ligament and alveolar bone were within physiologic limit.

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The Evaluation in Displacement Response of Tapered Tall Buildings to Wind Load (풍하중을 받는 테이퍼 고층건물의 진동변위응답 평가)

  • Cho, Ji-Eun;You, Ki-Pyo;Kim, Jong-Soo;Kim, Young-Moon
    • Journal of Korean Association for Spatial Structures
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    • v.5 no.4 s.18
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    • pp.101-108
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    • 2005
  • The investigations for mitigating wind-induced excitations of tall buildings have been carried out. The aerodynamic modification of a building shape changing the cross-section with height through tapering, which alters the flow pattern around the building, could reduce wind induced excitations of tall buildings. The fart that a tapered tall building might spread the vortex-shedding over a broad range of frequencies makes more effective for reducing acrosswind responses has been established. In this paper, to investigate the tapering effect for reducing wind-induced responses of a tapered tall building, high-frequency force-balance test was conducted. The six types of building models which have different taper ratio of 2.5%, 5%, 7.5%, 10%, 15% and one basic building model of a square cross-section were tested under the two typical boundary layers representing suburban and urban flow environment. The effect of wind direction was also considered.

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Aerodynamics of tapered and set-back buildings using Detached-eddy simulation

  • Sharma, Ashutosh;Mittal, Hemant;Gairola, Ajay
    • Wind and Structures
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    • v.29 no.2
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    • pp.111-127
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    • 2019
  • The tapered and set-back type of unconventional designs have been used earlier in many buildings. These shapes are aerodynamically efficient and offer a significant amount of damping against wind-induced forces and excitations. Various studies have been conducted on these shapes earlier. The present study adopts a hybrid approach of turbulence modelling i.e., Detached-eddy Simulation (DES) to investigate the effect of height modified tapered and set-back buildings on aerodynamic forces and their sensitivity towards pressure. The modifications in the flow field around the building models are also investigated and discussed. Three tapering ratios (T.R.=(Bottom width- Top width)/Height) i.e., 5%, 10%, 15% are considered for tapered and set-back buildings. The results show that, mean and RMS along-wind and across-wind forces are reduced significantly for the aerodynamically modified buildings. The extent of reduction in the forces increases as the taper ratio is increased, however, the set-back modifications are more worthwhile than tapered showing greater reduction in the forces. The pressure distribution on the surfaces of the buildings are analyzed and in the last section, the influence of the flow field on the forces is discussed.

Characteristics of Magnetic Resonance Arthrography Findings in Traumatic Posterosuperior Rotator Cuff Tears

  • Cho, Yung-Min;Kim, Sung-Jae;Oh, Jin-Cheol;Chun, Yong-Min
    • Clinics in Shoulder and Elbow
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    • v.18 no.4
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    • pp.211-216
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    • 2015
  • Background: Few studies have investigated magnetic resonance (MR) characteristics of traumatic posterosuperior rotator cuff tears involving the supraspinatus and infraspinatus. We hypothesized that traumatic rotator cuff tears may have MR characteristics distinguishable from those of non-traumatic tears. Methods: Preoperative MR arthrography and intraoperative tear size measurements were compared in 302 patients who underwent MR arthrography and subsequent arthroscopic rotator cuff repairs for traumatic (group T, 61 patients) or non-traumatic (group NT, 241 patients) tears. The inclusion criteria for both groups were posterosuperior full-thickness rotator cuff tear and age between 40 and 60 years. For group T, traumas were limited to accidental falls or slips, or sports injuries, motor vehicle accidents; injuries were associated with acute onset of pain followed by functional shoulder impairment; and time between injury and magnetic resonance imaging (MRI) was 6 weeks or less. Results: In group T, 72.1% of shoulders (44 patients) had tendon tears with blunt edges while 27.9% of shoulders (17 patients) had tears with tapering edges. In contrast, 21.2% of patients in group NT (51 patients) had blunt-edge tears, while 78.8% (190 patients) of tears had tapering edges. These results were statistically significant (p<0.001) and estimated odds ratio was 9.6. The size of tear did not vary significantly between groups. Conclusions: We found no exclusive MR characteristic to define traumatic tears. However, oblique coronal MRI of traumatic tears showed a significant tendency for abrupt and rough torn tendon edges and relatively consistent tendon thicknesses (without lateral tapering) compared to non-traumatic cuff tears.

End-Shape Effect for Stress Concentration Reduction of Composite Single-Lap Bonded Joint (끝단형상에 따른 복합소재 단일겹치기 체결부의 응력집중 저감에 관한 연구)

  • Kim, Jung-Seok;Hwang, Jae-Yeon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.3
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    • pp.333-340
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    • 2011
  • We evaluated the stress-reduction effect for different shapes of a composite adherend with or without a spew fillet. Six different single-lap joint specimens were modeled and assessed using nonlinear finite element analysis. Moreover, we investigated the effect of the stiffness ratio of the adherend and adhesive. The single-lap joint with normal tapering had the highest stress values, and the single-lap joint with reverse tapering and a spew fillet had the lowest stress values. The composite adherends with higher stiffness had lower stress values, and the adhesives with lower stiffness had lower stress values.