• Title/Summary/Keyword: Head loss

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Effects of Residual Hearing on the Auditory Steady State Response for Cochlear Implantation in Children

  • Kim, Young Seok;Han, Sun A;Woo, Hyunjun;Suh, Myung-Whan;Lee, Jun Ho;Oh, Seung Ha;Park, Moo Kyun
    • Journal of Audiology & Otology
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    • v.23 no.3
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    • pp.153-159
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    • 2019
  • Background and Objectives: We aim to explore the effects of residual auditory steady state response (ASSR) on cochlear implantation (CI) outcomes in children lacking auditory brainstem responses (ABRs). Subjects and Methods: We retrospectively reviewed the data of child CI recipients lacking ABRs. All ears were divided into two groups: with residual ASSR and without ASSR. For each frequency, the T- and C-levels and the electrical dynamic ranges of postoperative 3-month and 1-year mappings were compared between the groups. To evaluate speech perception, patients who received simultaneous bilateral CIs were divided into two groups: group 1 exhibited responses at all frequencies in both ears; in group 2, at least one ear evidenced no response. The Categories of Auditory Perception (CAP) and Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) scores were compared between the groups. Results: We enrolled 16 patients. At 2 kHz, the postoperative 3-month and 1-year T-levels of patients with residual hearing were lower than those of hearing loss group (p=0.001, p=0.035). In residual hearing group, the ASSR threshold correlated positively with the postoperative 1-year T-level (p=0.012, R2=0.276) and C-level (p=0.002, R2=0.374). Of 10 simultaneous bilateral CI recipients, 5 exhibited ASSRs at all frequencies and the other 5 showed no response at ≥1 frequency. The latter had higher CAP scores at the postoperative 1-year (p=0.018). Conclusions: In children exhibiting hearing loss in ABR testing, residual hearing at 2 kHz ASSR correlated positively with the post-CI T-level. Those with ASSRs at all frequencies had significantly lower CAP scores at the postoperative 1year. CI should not be delayed when marginal residual hearing is evident in ASSR.

Effects of Residual Hearing on the Auditory Steady State Response for Cochlear Implantation in Children

  • Kim, Young Seok;Han, Sun A;Woo, Hyunjun;Suh, Myung-Whan;Lee, Jun Ho;Oh, Seung Ha;Park, Moo Kyun
    • Korean Journal of Audiology
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    • v.23 no.3
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    • pp.153-159
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    • 2019
  • Background and Objectives: We aim to explore the effects of residual auditory steady state response (ASSR) on cochlear implantation (CI) outcomes in children lacking auditory brainstem responses (ABRs). Subjects and Methods: We retrospectively reviewed the data of child CI recipients lacking ABRs. All ears were divided into two groups: with residual ASSR and without ASSR. For each frequency, the T- and C-levels and the electrical dynamic ranges of postoperative 3-month and 1-year mappings were compared between the groups. To evaluate speech perception, patients who received simultaneous bilateral CIs were divided into two groups: group 1 exhibited responses at all frequencies in both ears; in group 2, at least one ear evidenced no response. The Categories of Auditory Perception (CAP) and Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) scores were compared between the groups. Results: We enrolled 16 patients. At 2 kHz, the postoperative 3-month and 1-year T-levels of patients with residual hearing were lower than those of hearing loss group (p=0.001, p=0.035). In residual hearing group, the ASSR threshold correlated positively with the postoperative 1-year T-level (p=0.012, R2=0.276) and C-level (p=0.002, R2=0.374). Of 10 simultaneous bilateral CI recipients, 5 exhibited ASSRs at all frequencies and the other 5 showed no response at ≥1 frequency. The latter had higher CAP scores at the postoperative 1-year (p=0.018). Conclusions: In children exhibiting hearing loss in ABR testing, residual hearing at 2 kHz ASSR correlated positively with the post-CI T-level. Those with ASSRs at all frequencies had significantly lower CAP scores at the postoperative 1year. CI should not be delayed when marginal residual hearing is evident in ASSR.

Follicular Thyroid Cancer with Multiple Bone Metastasis : A Case Report (갑상샘 여포암의 다발성 골전이 1예)

  • Sah, Dae Jin;Kwak, Seul Ki;Kim, Seung Woo
    • Korean Journal of Head & Neck Oncology
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    • v.28 no.2
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    • pp.143-145
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    • 2012
  • Follicular thyroid cancer(FTC) accounts for about 10-15% of thyroid cancer. Distant metastasis is common, usually to lung, bone and brain. 71-years-old man visited neurosurgery outpatient department. He complained of recent 6kg weight loss, left upper extremity pain with weakness and back pain. The radiologic findings showed multiple bone metastasis including thoracic spine and left scapular resulting from FTC. There was a probable brain metastatic lesion on right temporal fossa. The core biopsy of thyroid and thoracic spine(T11) confirmed metastatic follicular carcinoma. Radioactive iodine therapy and radiotherapy was done following total thyroidectomy. We report a unique case of multiple bone metastasis from follicular carcinoma of thyroid with literature review.

Osteoma of Temporal Bone Accompanying Cholesteatoma in the External Auditory Canal (외이도진주종을 동반한 측두골골종)

  • Park, Il Seok;Jeon, Seung Sik;Shim, Jung Weon;Hong, Seok Min
    • Korean Journal of Head & Neck Oncology
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    • v.31 no.1
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    • pp.47-49
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    • 2015
  • An osteoma of the external auditory canal(EAC) is an uncommon benign tumor. If a canal obstruction occurs, ear fullness or conductive hearing loss can arise. But, the association of an osteoma with a cholesteatoma is extremely rare. Therefore, we report a case of a 35-year-old female patient with osteoma of temporal bone that was complicated with EAC cholesteatoma.

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Experimental Study on the Characteristics of Thermal Sensitivity for Fusible Alloy Type Sprinkler Head (가용합금형 스프링클러 헤드의 열감도 특성에 관한 실험적 연구)

  • 권오승;이진호
    • Fire Science and Engineering
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    • v.9 no.1
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    • pp.20-29
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    • 1995
  • The sprinkler head is a component of the sprinkler system intended to discharge water for automatic detection and extinguishment of fires. On this study, thermal characteristic values affecting the sensitivity of the fusible alloy type sprinkler head were obtained and analyzed under heated air stream condition which had constant temperature and velocity. The experiment was carried out under the forced convection condition with both the conductive heat loss considered and neglected. The thermal characteristic values of the sprinkler head were obtained in accordance with the material and shape of the heat responsive element and the conditions of the main body.

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Rapidly Progressive Osteonecrosis of the Humeral Head after Arthroscopic Bankart and Rotator Cuff Repair in a 66-Year Old Woman: A Case Report

  • Cho, Hyun IK;Cho, Hyung Lae;Hwang, Tae Hyok;Wang, Tae Hyun;Cho, Hong
    • Clinics in Shoulder and Elbow
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    • v.18 no.3
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    • pp.167-171
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    • 2015
  • Humeral head chondrolysis has been widely reported as a devastating complication after arthroscopic shoulder surgery; however little is known about post-arthroscopic humeral head osteonecrosis. We experienced a 66-year-old female patient with rapidly progressive osteonecrosis of the humeral head only seven months after arthroscopic Bankart and rotator cuff repair. The patient had no systemic risk factors for osteonecrosis. A satisfactory result was achieved with reverse total shoulder arthroplasty for severe humeral head destruction and an irreparable massive rotator cuff tear. Shoulder surgeons should be aware of such severe complication, perform routine radiographs, and pay close attention to the presence of constant pain or loss of motion after arthroscopic shoulder surgery.

A Study on the Distribution of Hydraulic Head Along the Lateral in a Pilot-Scale Riverbank Filtration (강변여과에서 파일럿규모 수평집수관의 수두분포 연구)

  • Jeong, Jae-Min;Park, Jae-Young;Lee, Jong-Jin;Kim, Yong-Woon;Kim, Seung-Hyun
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.5
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    • pp.334-339
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    • 2013
  • A pilot-scale sand-box experiment simulating a lateral of collector well used in riverbank filtration was performed, and hydraulic head distributions along the lateral were measured according to the various drawdowns at the well. The results of this experiment were compared to the predicted values obtained using a theory previously developed by Kim in order for its validation. This theory predicts the head loss in a large-scale lateral given the loss in a small-scale one, and to have actual values for comparison, the results from a lab-scale experiment previously performed by Kim were employed. Comparing the experimental values to the extrapolated value indeed confirmed the validity of the theory. A procedure to determine the hydraulic head distribution of a practical-scale lateral was also presented applying the theory to the experimental result of this study in an effort to show the process of lateral design for riverbank filtration.

Risk Factors of Intracranial Hemorrhage in Skull Fracture after Pediatric Head Trauma (두부 외상 후 두개골 골절 환아의 두개내 출혈 위험요인)

  • Ji, Myoung-Hee;Choi, Hye-Ran
    • Journal of Korean Biological Nursing Science
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    • v.22 no.1
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    • pp.45-52
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    • 2020
  • Purpose: The purpose of this study was to investigate the risk factors of intracranial hemorrhage in children with skull fractures from head trauma. Methods: The retrospective study included 205 patients diagnosed with a skull fracture in a pediatric emergency room. Data were analyzed using 𝓍2-test, Fisher's exact test, t-test, and logistic regression analysis with the SPSS/WIN24.0 program. Results: Intracranial hemorrhage was diagnosed in 71 patients. There were statistically significant differences between the hemorrhagic group and non-hemorrhagic group in age group, places of accident, type of accident, location of the fracture, and symptoms. Intracranial hemorrhage by age group was higher in school-age and adolescence than in infancy. The places of accidents of hemorrhage were higher in street and school than in the home. The types of an accident of bleeding were higher in the case of knock and traffic accident than in fall. Symptoms of nausea, headache, and loss of consciousness were associated with higher intracranial hemorrhage. Multivariable logistic regression analysis showed that knock (OR= 3.29, 95% CI= 1.50-7.22), traffic accident (OR= 4.78, 95% CI= 1.31-17.43), nausea (OR= 4.18, 95% CI= 1.42-12.31), and loss of consciousness (OR= 3.29, 95% CI= 1.41-9.50) were risk factors for intracranial hemorrhage. Conclusion: In this study, the risk factors of intracranial hemorrhage were identified in pediatric patients with skull fractures caused by head trauma. It is recommended that the results of this study be used to manage and educate patients, caregivers, and medical staff after head trauma hemorrhage.

Design of Tidal Basin Using Automatically Controlled Manifold System (분기관의 자동제어를 통한 조석수조의 설계)

  • 전인식;오영민;이달수
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.6 no.4
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    • pp.327-334
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    • 1994
  • The manifold designates a pipe system discharging or absorbing water through multiple holes installed along the finite length of the pipe. The proper design of the manifold requires the pre-analysis of the hydraulic characteristics such as system head and flow rate. head loss and hole discharges, etc. On the contrary to the general pipe systems. the head loss along the pipe is hardly quantified in an explicit way since it is complicately varied by the size and arrangement of the holes. In the present study, both energy and continuity equations are employed to analyze the hydraulic characteristics, constituting nonlinear simultaneous equations which are solved by Newton method. In addition, a hydraulic experiment utilizing the manifold system equipped with an automatically controlled valve is performed to reproduce model tide. The result shows that the manifold system can be effectively used in a tidal basin where water flow should be maintained uniformly over the basin width.

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Ranking subjects based on paired compositional data with application to age-related hearing loss subtyping

  • Nam, Jin Hyun;Khatiwada, Aastha;Matthews, Lois J.;Schulte, Bradley A.;Dubno, Judy R.;Chung, Dongjun
    • Communications for Statistical Applications and Methods
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    • v.27 no.2
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    • pp.225-239
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    • 2020
  • Analysis approaches for single compositional data are well established; however, effective analysis strategies for paired compositional data remain to be investigated. The current project was motivated by studies of age-related hearing loss (presbyacusis), where subjects are classified into four audiometric phenotypes that need to be ranked within these phenotypes based on their paired compositional data. We address this challenge by formulating this problem as a classification problem and integrating a penalized multinomial logistic regression model with compositional data analysis approaches. We utilize Elastic Net for a penalty function, while considering average, absolute difference, and perturbation operators for compositional data. We applied the proposed approach to the presbyacusis study of 532 subjects with probabilities that each ear of a subject belongs to each of four presbyacusis subtypes. We further investigated the ranking of presbyacusis subjects using the proposed approach based on previous literature. The data analysis results indicate that the proposed approach is effective for ranking subjects based on paired compositional data.