• Neonatal Medicine
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• v.28 no.1
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• pp.7-13
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• 2021

Purpose: To evaluate the risk factors and effects of fluctuations in oxygen saturation on the occurrence and severity of retinopathy of prematurity (ROP). Methods: From January 1, 2013 to January 31, 2020, 260 patients hospitalized in the neonatal intensive care unit of Ajou University Hospital were retrospectively analyzed. Results: Sixty-six patients (25%) were diagnosed with ROP; of them 39 required treatment. In the multivariate regression analysis of ROP severity, the odds ratio (OR) of gestational age was 0.32 (95% confidence interval [CI], 0.22 to 0.47; P<0.0001). The OR of saturation of peripheral oxygen (SpO₂) fluctuations at the 4th week after birth was 1.02 (95% CI, 1.02 to 1.12; P=0.041). Conclusion: SpO₂ fluctuations in premature infants younger than 30 weeks' gestational age affects ROP severity, especially at the 4th week of life.

• Clinical and Experimental Pediatrics
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• v.52 no.1
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• pp.50-55
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• 2009

Purpose : This study aimed to determine the influence of low-dose oxygen ($FiO_2$ <25%) therapy through nasal cannulae on the progress and prognosis of retinopathy of prematurity (ROP) as well as methods of preventing ROP. Methods : Our subjects comprised premature infants (gestation period <37 weeks; birth weight <1,750 g) born in Daegu Fatima Hospital between February 1, 2001 and January 31, 2006. We retrospectively reviewed and analyzed the medical records of 273 patients who were available for eye examination and follow up over 6 months. Results : The factors maximally influencing the occurrence of ROP were low gestation age and low birth weight. We observed that the incidence of ROP increased with the increasing duration of low-dose oxygen therapy. ROP onset was delayed during ongoing oxygen therapy; however, rapid progression of ROP occurred after the discontinuation of oxygen therapy among premature infants up to the prethreshold stage. Conclusion : To prevent of occurrence of severe ROP and its rapid progression, the period of low-dose oxygen therapy needs to be shortened. Moreover, frequent eye examinations should be performed after the discontinuation of oxygen therapy.

• Journal of KIISE
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• v.41 no.12
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• pp.1018-1025
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• 2014

An ROP attack creates gadget sequences which consist of existing code snippets in a program, and hijacks the control flow of a program by chaining and executing gadget sequences consecutively. Existing defense schemes have limitations in that they cause high execution overhead, an increase in the binary size overhead, and a low applicability. In this paper, we solve these problems by introducing zero-sum defender, which is a fast and space-efficient mitigation scheme against ROP attacks. We find a fundamental property of gadget execution in which control flow starts in the middle of a function without a call instruction and ends with a return instruction. So, we exploit this property by monitoring whether the execution is abused by ROP attacks. We achieve a very low runtime overhead with a very small increase in the binary size. In our experimental results, we verified that our defense scheme prevents real world ROP attacks, and we showed that there is only a 2% performance overhead and a 1% binary size increase overhead in several benchmarks.

• Clinical and Experimental Pediatrics
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• v.53 no.6
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• pp.694-700
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• 2010

Purpose: To assess the validity of individual and combined prognostic effects of severe bronchopulmonary dysplasia (BPD), brain injury, retinopathy of prematurity (ROP), and parenteral nutrition associated cholestasis(PNAC). Methods: We retrospectively analyzed the medical records of 80 extremely low birthweight (ELBW) infants admitted to the neonatal intensive care unit (NICU) of the Severance Children's Hospital, and who survived to a postmenstrual age of 36 weeks. We analyzed the relationship between 4 neonatal morbidities (severe BPD, severe brain injury, severe ROP, and severe PNAC) and poor outcome. Poor outcome indicated death after a postmenstrual age of 36 weeks or survival with neurosensory impairment (cerebral palsy, delayed development, hearing loss, or blindness) between 18 and 24 months of corrected age. Results: Each neonatal morbidity correlated with poor outcome on univariate analysis. Multiple logistic regression analysis revealed that the odds ratios (OR) were 4.9 (95% confidence interval [CI], 1.0-22.6; $P$=0.044) for severe BPD, 13.2 (3.0-57.3; $P$<.001) for severe brain injury, 5.3 (1.6-18.1; $P$=0.007) for severe ROP, and 3.4 (0.5-22.7; $P$=0.215) for severe PNAC. Severe BPD, brain injury, and ROP were significantly correlated with poor outcome, but not severe PNAC. By increasing the morbidity count, the rate of poor outcome was significantly increased (OR 5.2; 95% CI, 2.2-11.9; $P$<.001). In infants free of the above-mentioned morbidities, the rate of poor outcome was 9%, while the corresponding rates in infants with 1, 2, and more than 3 neonatal morbidities were 46%, 69%, and 100%, respectively. Conclusion: In ELBW infants 3 common neonatal mornidifies, severe BPD, brain injury and ROP, strongly predicts the risk of poor outcome.

• Korean Journal of Ophthalmology
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• v.32 no.6
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• pp.451-458
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• 2018

Purpose: To investigate the efficacy, safety, and anatomical outcomes associated with intravitreal anti-vascular endothelial growth factor (VEGF) treatment of retinopathy of prematurity (ROP). Methods: We performed a retrospective review of intravitreal anti-VEGF (bevacizumab or ranibizumab) treatment of 153 eyes (83 infants) diagnosed with ROP at two tertiary hospitals from June 2011 to January 2017. The primary outcome was the rate of recurrence requiring additional treatment; secondary outcomes included incidence of major complications and final refractive error. Results: A total of 101 eyes were treated with bevacizumab, and 52 with ranibizumab. The bevacizumab and ranibizumab groups were characterized by mean birthweights of $941.8{\pm}296.1$ and $1,257.7{\pm}514.5g$, gestational ages at birth of $26.9{\pm}1.9$ and $28.1{\pm}3.2$ weeks, and postmenstrual ages at treatment of $40.4{\pm}2.4$ and $39.2{\pm}2.3$ weeks, respectively. The two groups differed significantly in birthweights and gestational ages at birth, but not in postmenstrual ages at treatment. The mean follow-up duration was $30.9{\pm}18.4$ months for the bevacizumab group, and $13.9{\pm}12.5$ months for ranibizumab. More cases were classified as zone 1 ROP in the ranibizumab group (44.2% vs. 11.9%, p < 0.001). Major surgical interventions included scleral encircling and vitrectomy (one and two eyes, respectively, both in the bevacizumab group). Retinal detachment was noted in one eye treated with bevacizumab. There was no significant difference in the most recent spherical equivalence for the two groups ($+0.10{\pm}3.66$ and $+0.22{\pm}3.00$ diopters for bevacizumab and ranibizumab, respectively). Univariable analysis revealed that only ROP stage influenced the occurrence of major complications (odds ratio, 9.046; p = 0.012). Conclusions: Intravitreal anti-VEGF treatment of ROP with both bevacizumab and ranibizumab achieved stable retinal vascularization with a low rate of complications and recurrence. Ranibizumab achieved similar anatomical outcomes as bevacizumab, without additional risk for major complications.

• Parasites, Hosts and Diseases
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• v.57 no.5
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• pp.543-547
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• 2019

Toxoplasma gondii can infect humans worldwide, causing serious diseases in pregnant women and immunocompromised individuals. T. gondii rhoptry protein 13 (ROP13) is known as one of the key proteins involved in host cell invasion. In this study, we generated virus-like particles (VLPs) vaccine expressing T. gondii rhoptry ROP13 and investigated VLPs vaccine efficacy in mice. Mice immunized with ROP13 VLPs vaccine elicited significantly higher levels of T. gondii-specific IgG, IgG1, IgG2a, and IgA antibody responses following boost immunization and challenge infection, whereas antibody inductions were insignificant upon prime immunization. Differing immunization routes resulted in differing antibody induction, as intranasal immunization (IN) induced greater antibody responses than intramuscular immunization (IM) after boost and challenge infection. IN immunization induced significantly higher levels of IgG and IgA antibody responses from feces, antibody-secreting cells (ASCs), $CD4^+$ T, $CD8^+$ T cells and germinal center B cell responses in the spleen compared to IM immunization. Compared to IM immunization, IN immunization resulted in significantly reduced cyst counts in the brain as well as lesser body weight loss, which contributed to better protection. All of the mice immunized through either route survived, whereas all na?ve control mice perished. These results indicate that the ROP13 VLPs vaccine could be a potential vaccine candidate against T. gondii infection.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.67.2-67
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• 2001

• Geomechanics and Engineering
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• v.37 no.3
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• pp.223-241
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• 2024

Evaluating the performance of Tunnel Boring Machines (TBMs) stands as a pivotal juncture in the domain of hard rock mechanized tunneling, essential for achieving both a dependable construction timeline and utilization rate. In this investigation, three advanced artificial neural networks namely, gated recurrent unit (GRU), back propagation neural network (BPNN), and simple recurrent neural network (SRNN) were crafted to prognosticate TBM-rate of penetration (ROP). Drawing from a dataset comprising 1125 data points amassed during the construction of the Alborze Service Tunnel, the study commenced. Initially, five geomechanical parameters were scrutinized for their impact on TBM-ROP efficiency. Subsequent statistical analyses narrowed down the effective parameters to three, including uniaxial compressive strength (UCS), peak slope index (PSI), and Brazilian tensile strength (BTS). Among the methodologies employed, GRU emerged as the most robust model, demonstrating exceptional predictive prowess for TBM-ROP with staggering accuracy metrics on the testing subset (R² = 0.87, NRMSE = 6.76E-04, MAD = 2.85E-05). The proposed models present viable solutions for analogous ground and TBM tunneling scenarios, particularly beneficial in routes predominantly composed of volcanic and sedimentary rock formations. Leveraging forecasted parameters holds the promise of enhancing both machine efficiency and construction safety within TBM tunneling endeavors.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.2
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• pp.253-270
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• 2021

This survey provides research into developing knee braces to protect the knee against damage, reduce knee pain, and strengthen the knee. A total of 235 surveys were conducted from December 2019 to January 2020. The subjects were adults in their 20s and over who lived in the Seoul metropolitan area and had experience of using knee braces. In terms of age differences, subjects over 60 years of age purchased knee braces mostly to secure a reduction of pain (ROP), whereas subjects in their 20s and 30s purchased knee braces for physical shock protection (PSP). Subjects in their 40s and 50s purchased knee braces for improvement of muscle movement (IMM). There was no significant difference in shape, material, and locking method based on the reason for wearing the knee brace. These results show that it is conceivable and maybe preferable to produce different knee braces-with a variety of shapes, materials, and locking materials-according to the reason behind wearing a knee brace. Knee braces are worn currently without any differentiation despite the findings of this study. In particular, we argue the need for functional and differentiated development of knee braces specifically for PSP, ROP, and IMM.

• Journal of the Korean Chemical Society
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• v.32 no.5
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• pp.495-500
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• 1988

The trans effect has been interpreted for a series of trans-[PtNH$_3$Cl$_2$2L] (L = H$_2$O, NH$_3$, Cl$^-$, Br$^-$, I$^-$, CH$_3$ and PH$_3$) and PtCl$_4^{-2}$ by means of our modified-EHMO method. The calculation shows that reduced overlap population(ROP) of Pt-N bond trans to L is decreased with a better trans director. That is, the trans effect has been found to be enhanced with a better trans director. Accordingly, it could be interpreted quantum chemically the trans effect for a general trans-PtTL$_2$X complex.