• Title/Summary/Keyword: system closure

Search Result 365, Processing Time 0.033 seconds

Decreased Expression of PTEN in Olfactory Bulb of Rat Pub after Naris Closure

  • Cho, Jae-Young;Lee, Sang-Hyun;Lee, Geon-Hee;Chun, Wan-Joo;Park, Yee-Tae;Lim, So-Young;Kim, Sung-Soo
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.8 no.1
    • /
    • pp.17-20
    • /
    • 2004
  • PTEN (phosphatase and tensin homolog) is a dual specific phosphatase antagonizing phosphoinositide 3-kinase activity, and has first been cloned as a tumor suppressor for glioma. Although the role of PTEN as a tumor suppressor has been well studied, little is known about signaling mechanisms regulating expression and/or activity of PTEN in the central nervous system. In this study, we investigated whether PTEN expression is regulated by sensory deprivation. P5 rat pups were unilaterally naris-closed, and olfactory bulbs were immunohistochemically analyzed with PTEN antibody at the $7^{th}$ day after naris closure. PTEN immunoreactivity was found to be down-regulated in both glomerular, external plexiform and subependymal cell layers, suggesting that odor deprivation signals down-regulate expression of PTEN in the olfactory bulb. To the best of our knowledge, this is the first report to suggest that PTEN expression is regulated by sensory deprivation signals in neonatal rats.

A Study on the Application of Closed School through Regional Analysis: Focused on the Gyeonggi-do Office of Education (지역분석을 통한 폐교 활용 방안: 경기도교육청을 중심으로)

  • Lee, Mi-young;Kang, Myung-gu;Choi, Jun-yeol
    • Journal of the Korean Regional Science Association
    • /
    • v.37 no.3
    • /
    • pp.37-46
    • /
    • 2021
  • The closure of education office is due to a decrease in the number of students, but it is necessary to look at various causes of this decrease. In particular, unlike other regions, Gyeonggi Province has a large number of students due to redevelopment, relocation of businesses, and changes in school districts. In addition, it is necessary to set the overall direction for the use of closed schools and seek ways to establish an efficient operation and management system in preparation for the changing future of the educational environment. Through this study, the closure of schools in Gyeonggi-do is different from that of local schools. The measures to utilize closed schools in Gyeonggi-do Province should be different and contribute to realizing the utilization of closed schools.

Low incidence of maxillary hypoplasia in isolated cleft palate

  • Azouz, Vitali;Ng, Marilyn;Patel, Niyant;Murthy, Ananth S.
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.42
    • /
    • pp.8.1-8.5
    • /
    • 2020
  • Background: The cause of maxillary growth restriction in patients with cleft lip and palate remains controversial. While studies have investigated the effects surgical technique and timing have on maxillary growth, few focus on patients with isolated cleft palate (ICP). The purpose of this study was to determine the impact palate repair and its associated complications may have on maxillary growth. Methods: A retrospective chart review of ICP patients who underwent palatoplasty from 1962 to 1999 at Akron Children's Hospital was performed. Patient demographics, Veau type, age at primary repair, closure technique, presence of fistula or velopharyngeal insufficiency (VPI), number of palatal operations, maxillary hypoplasia (MH) frequency, and follow-up were recorded. Exclusion criteria included patients with cleft lip, submucous cleft, or syndromes. Results: Twenty-nine non-syndromic ICP patients were identified; 62% (n = 18) had Veau type 1 and 38% (n = 11) had Veau type 2. All patients underwent 2-flap or Furlow palatoplasty with mobilization of mucoperiosteal flaps. Vomerine flaps were used in all Veau 2 cleft palate closures. Palatoplasty was performed at a mean age of 19.9 ± 8.2 months. Average follow-up was 209 ± 66.5 months. The rate of VPI was 59% (n = 17) and the rate of oronasal fistula was 14% (n = 4). Conclusions: There was a low incidence of MH despite complications after initial palate closure. Our results seem to suggest that age at palate closure, type of cleft palate, and type of surgical technique may not be associated with MH. Additionally, subsequent procedures and complications after primary palatoplasty such as VPI and palatal fistula may not restrict maxillary growth.

COMPUTATION OF TURBULENT NATURAL CONVECTION WITH THE ELLIPTIC-BLENDING SECOND-MOMENT CLOSURE (타원혼합 이차모멘트 모델을 사용한 난류 자연대류 해석)

  • Choi, S.K.;Han, J.W.;Kim, S.O.;Lee, T.H.
    • Journal of computational fluids engineering
    • /
    • v.21 no.4
    • /
    • pp.102-111
    • /
    • 2016
  • In this paper a computation of turbulent natural convection in enclosures with the elliptic-blending based differential and algebraic flux models is presented. The primary emphasis of the study is placed on an investigation of accuracy of the treatment of turbulent heat fluxes with the elliptic-blending second-moment closure for the turbulent natural convection flows. The turbulent heat fluxes in this study are treated by the elliptic-blending based algebraic and differential flux models. The previous turbulence model constants are adjusted to produce accurate solutions. The proposed models are applied to the prediction of turbulent natural convections in a 1:5 rectangular cavity and in a square cavity with conducting top and bottom walls, which are commonly used for validation of the turbulence models. The relative performance between the algebraic and differential flux model is examined through comparing with experimental data. It is shown that both the elliptic-blending based models predict well the mean velocity and temperature, thereby the wall shear stress and Nusselt number. It is also shown that the elliptic-blending based algebraic flux model produces solutions which are as accurate as those by the differential flux model.

The efficacy and safety of transcatheter closure of atrial septal defect with Amplatzer septal occluder in young children less than 3 years of age (3세 미만 심방중격결손 소아에서 Amplatzer 기구 폐쇄술의 안전성 및 효용성)

  • Lee, Soo Hyun;Choi, Deok Young;Kim, Nam Kyun;Choi, Jae Young;Sul, Jun Hee
    • Clinical and Experimental Pediatrics
    • /
    • v.52 no.4
    • /
    • pp.494-498
    • /
    • 2009
  • Purpose : Applicability of transcatheter closure of atrial septal defect (ASD) has been expanded by accumulation of clinical experiences and evolutions of the device. This study was performed to evaluate the safety and efficacy of transcatheter closure of ASD with Amplatzer septal occluder (ASO) in young children less than 3 years of age. Methods : From May 2003 to December 2005, 295 patients underwent transcatheter closure of ASD with ASO in the Severance Cardiovascular Hospital, Yonsei University Health System. Among them, 51 patients less than 3 years of age were enrolled in this study. We investigated procedural success rate, rate of residual shunt, frequency of complications, procedure/fluoroscopy time, and need of modified techniques for device implantation. Results : The median age was 2.1 years and median body weight was 12 kg. Implantation of device was successful in 50 patients (98%). Seven patients (15%) showed a small residual shunt 1 day after the procedure, but complete occlusion had been documented at 6 month follow-up in all patients (100%). The pulmonary to systemic flow ratio (Qp/Qs), peak systolic pulmonary artery pressure, and peak systolic right ventricular pressure had decreased significantly after closure of ASD. There were 2 complications including device embolization (1, 2%) and temporary groin hematoma (1, 2%). Conclusion : Transcatheter closure of ASD with ASO can be performed with satisfactory results and acceptable risk even in young children less than 3 years of age. We could suggest that even in very young children with ASD, there is no need to wait until they grow to a sufficient size for the transcatheter closure.

Influence of Internal Resonance on Responses of a Spring-Pendulum System under Broad Band Random Excitation (광대역 불규칙 가진력을 받는 탄성진자계의 내부공진효과)

  • 이원경;조덕상
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 1997.04a
    • /
    • pp.86-94
    • /
    • 1997
  • An investigation into the modal interaction of an autoparametric system under broad-band random excitation is made. The specific system examined is a spring-pendulum system with internal resonance, which is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. By means of the Gaussian closure method the dynamic moment equations explaining the random response of the system are reduced to a system of autonomous ordinanary differential equations of the first and second moments. In view of equilibrium solutions of this system and their stability we examine the system responses. The stabilizing effect of system damping is also examined.

  • PDF

Comparison Between Two Analytical Solutions for Random Vibration Responses of a Spring-Pendulum System with Internal Resonance (내부공진을 가진 탄성진자계의 불규칙진동응답을 위한 두 해석해의 비교)

  • 조덕상;이원경
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 1998.04a
    • /
    • pp.399-406
    • /
    • 1998
  • An investigation into the stochastic bifurcation and response statistits of an autoparameteric system under broad-band random excitation is made. The specific system examined is a spring-pendulum system with internal resonance, which is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. The Fokker-Planck equations is used to generate a general first-order differential equation in the dynamic moment of response coordinates. By means of the Gaussian and non-Gaussian closure methods the dynamic moment equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. In view of equilibrium solutions of this system and their stability we examine the stochastic bifurcation and response statistics. The analytical results are compared with results obtained by Monte Carlo simulation.

  • PDF

Nonlinear Vibration Responses of a Spring-Pendulum System under Random Base Excitation (불규칙 지반 가진력을 받는 탄성진자계의 비선형진동응답)

  • Cho, Duk-Sang
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.18 no.3
    • /
    • pp.175-181
    • /
    • 2001
  • An investigation into the response statistics of a spring-pendulum system whose base oscillates randomly along vertical and horizontal line is made. The spring-pendulum system with internal resonance examined is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. The Fokker-Planck equation is used to generate a general first-order differential equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. In view of equilibrium solutions of this system and their stability, the response statistics is examined. It is seen that increase in horizontal excitation level leads to a decreased width of the internal resonance region.

  • PDF

Flocculation and Retention Phenomena of Microparticle Retention Systems Based on Cationic Guar Gums and Colloidal Silicas (양이온성 구아 검과 콜로이달 실리카를 이용한 보류시스템의 응집 및 보류 현상)

  • 함충현;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.33 no.4
    • /
    • pp.1-6
    • /
    • 2001
  • Today's paper industry tries to use greater amount of high yield pulp and recycled fiber and to close mill water system, which results in higher fines content and buildup of organic and inorganic contaminants in white water system. Researches are being focused to develop chemical additives that provide good retention and drainage in a closed papermaking system. A microparticle retention system consisted of cationic guar gum and anionic colloidal silica so has been developed to meet the requirements for improving machine speed and product quality. The objective of this investigation was to determine the effects of the degree of cationic guar gums, charge density and structure of anionic colloidal silica sols, and the degree of system closure on the performances of this microparticle retention system. Cationic guar gums and anionic colloidal silica sols with higher charge densities showed better retention performance. Particularly, wider maximum in retention was obtained when structure colloidal silica was used suggesting as mechanism of microparticle bridging is functioning in this system.

  • PDF

A Study on the Structure of Turbulent non-Premixed Oxy-fuel Flame Using CMC Model-based Simulation (CMC 모델 기반 수치해석을 사용한 순산소 난류확산화염 구조 연구)

  • Kim, Jong-Soo;Sreedhara, S.;Huh, Kang-Yeol;Yang, Won
    • Journal of the Korean Society of Combustion
    • /
    • v.13 no.1
    • /
    • pp.31-43
    • /
    • 2008
  • Oxy-fuel flame has a significantly different structure from that of air-fuel flame because of its high temperature. This study is aimed to find out the difference of the oxy-fuel flame structure in order to understand reaction mechanism closely, which is crucial to design real-scale oxy-fuel combustion system. By examining pictures of counterflow flame and LIF images, we found that oxy-fuel flame had two-zone structure: fuel decomposition region and distributed CO oxidation region. In the oxy-fuel flame, OH radical was distributed intensely through the whole flame due to its higher flame temperature than crossover temperature. For showing those features of the oxy-fuel flame, 1 MW scale IFRF oxy-natural gas burner was simulated by conditional moment closure(CMC) model. Calculation results were compared with experimental data, and showed agreements in trend. In the simulated distributions of fuel decomposition/CO oxidation rates, CO oxidation region was also separated from fuel decomposition zone considerably, which showed the two-zone structure in the oxy-fuel flame.

  • PDF