• Archives of Craniofacial Surgery
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• v.17 no.4
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• pp.211-217
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• 2016

Background: Nonsyndromic craniosynostosis is a relatively common craniofacial anomaly and various techniques were introduced to achieve its operative goals. Authors found that by using smaller bone fragments than that used in conventional cranioplasty, sufficiently rigid bone union and effective regeneration capacity could be achieved with better postoperative outcome, only if their stable fixation was ensured. Methods: Through bicoronal incisional approach, involved synostotic cranial bone together with its surrounding areas were removed. The resected bone flap was split into as many pieces as possible. The extent of this 'multi-split osteotomy' depends on the degree of dysmorphology, expectative volume increment after surgery and probable dead space caused by bony gap between bone segments. Rigid interosseous fixation was performed with variable types of absorbable plate and screw. In all cases, the pre-operational three-dimensional computed tomography (3D CT) was checked and brain CT was taken immediately after the surgery. Also about 12 months after the operation, 3D CT was checked again to see postoperative morphology improvement, bone union, regeneration and intracranial volume change. Results: The bony gaps seen in the immediate postoperative brain CT were all improved as seen in the 3D CT after 12 months from the surgery. No small bone fragment resorption was observed. Brain volume increase was found to be made gradually, leaving no case of remaining epidural dead space. Conclusion: We conclude that it is meaningful in presenting a new possibility to be applied to not only nonsyndromic craniosynostosis but also other reconstructive cranial vault surgeries.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.1
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• pp.35-40
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• 1999

Recently, sagittal split ramus oseotomy and intraoral vertical ramus osteotomy have been commonly performed for the correction of mandibular prognathism, occurred to abundant oriental people. Many authors have studied the soft tissue change after orthognathic surgery, especially between mandibular hard tissues and soft tissue of lower lip, but the study of upper lip change is comparatively little. Therefore, we studied the 12 patients, operated only sagittal split ramus osteotomy without genioplasty or maxillary osteotomy in department of oral and maxillofacial surgery, Hanyang university hospital from 1996. 1. 1. to 1998. 7. 20. Preoperative and postoperative cephalometric view was measured to know the change of upper lip position and shape after mandibular setback. The result were obtained as follows. 1. The ratio of upper lip change amount to lower incisor horizontal movement was 15.1%. 2. The ratio of lower facial profile between Sn-Stm and Stm-Mes was changed from 1 : 2.352 to 1 : 2.069 after operation. 3. Post-operative upper lip was flattened 72.4% compared with pre-operative one. 4. The vermilion zone of the upper lip increased 56 % horizontally, 5.8% vertically after operation. 5. The vermilion zone ratio of the lower lip to the upper lip was changed from 1 : 1.253 to 1 : 1.348. 6. The distance between esthetic line and Ls was changed from -3.958mm to -1.15mm.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.4
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• pp.246-257
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• 2024

Purpose: Administering early parenteral amino acids to very low birth weight (VLBW) premature infants (birth body weight [BBW]<1,500 g) is challenging due to factors such as holidays, cost, and access to sterile compounding facilities. Using advance-prepared parenteral nutrition (PN) may address this issue and should be evaluated for its safety and potential benefits. Methods: We extracted data from medical records collected between July 2015 and August 2019. VLBW infants received PN for at least seven days and were split into two groups: the traditional group (n=30), which initially received a glucose solution and then PN on workdays, and the pre-preparation group (n=16), which received advance-prepared PN immediately upon admission to the neonatal intensive care unit. Results: The median BBWs of the traditional and pre-preparation groups were 1,180.0 vs. 1,210.0 g. In the initial two days, the pre-preparation group had a significantly higher amino acid intake (2.23 and 2.24 g/kg/d) than the traditional group (0 and 1.78 g/kg/d). The pre-preparation group exhibited greater head circumference growth ratio relative to birth (7th day: 1.21% vs. -3.57%, p=0.014; 21st day: 7.71% vs. 3.31%, p=0.017). No significant differences in metabolic tolerance were observed. Conclusion: Advanced preparation of PN can be safely implemented in VLBW preterm infants, offering advantages such as early, higher amino acid intake and improved head circumference growth within the first 21 days post-birth. This strategy may serve as a viable alternative in settings where immediate provision of sterile compounding facilities is challenging.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.206-216
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• 2000

Predictional study for lateral change between pre- and post-orthognathic surgery has been emphasized mainly on anterior area of lateral profile; upper lip, lower lip and chin et al. So interest for lateral profile change has been less in posterior area of lateral profile and literature analyzing gonial angle change is rare. The purpose of this study is to make prediction for gonial angle change possible and to offer somewhat treatment guidance for gonial angle to be improved by investigating overall gonial angle change between pre- and post-orthognathic surgery and inquiring into factors influencing on pattern of genial angle change. For this study 35 patients were selected retrospectively. Lateral cephalometric radiographs were taken in just pre-op time, pod 1 day, pod 1 year. They were analyzed and genial angles were measured. The results were as follows : 1. Gonial angle at pod 1 day was decreased about $9.3^{\circ}$ than pre-op and gonial angle at pod 1 year was increased about $4.0^{\circ}$ than pod 1 day. So genial angle at pod 1 year was decreased about $5.3^{\circ}$ than pre-op genial angle(p<0.01). 2. Mean pre-op gonial angle was $129.4^{\circ}$, showing significantly high value than normal and mean gonial angle at pod 1 year was $124.1^{\circ}$, showing value near to normal. 3. Mean gonial angle change between pre-op and pod 1 year was decreased about $5.4^{\circ}$ in female and $5.3^{\circ}$ in male. There was no statistically significant difference between male and female(p>0.05). 4. Principal factor influencing on decreased gonial angle in gonial angle change between pre-op and pod 1 year was amount of mandibular setback. 5. Principal factor influencing on increased gonial angle in gonial angle change between pod 1 day and pod 1 year was % horizontal relapse, and it was thought that resorption and bone remodelling on posterior area in mandibular distal segment also were related to increased gonial angle. 6. It is thought that sagittal split ramus osteotomy in mandibular prognathic patients with high value of gonial angle is effective to improvement of gonial angle, and In patients who have normal range of gonial angle and are required with excessive mandibular setback, short lingual cut method, additional resection of posterior margin of distal segment, Obwegeser II method will be considerd. 7. More prudent operation and careful post-op management will be responsible for maintenance of postoperative stable gonial angle.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1442-1462
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• 2014

Packet classification is a key technology of the Internet for routers to classify the arriving packets into different flows according to the predefined rulesets. Previous packet classification algorithms have mainly focused on search speed and memory usage, while overlooking update performance. In this paper, we propose PreCuts, which can drastically improve the update speed. According to the characteristics of IP field, we implement three heuristics to build a 3-layer decision tree. In the first layer, we group the rules with the same highest byte of source and destination IP addresses. For the second layer, we cluster the rules which share the same IP prefix length. Finally, we use the heuristic of information entropy-based bit partition to choose some specific bits of IP prefix to split the ruleset into subsets. The heuristics of PreCuts will not introduce rule duplication and incremental update will not reduce the time and space performance. Using ClassBench, it is shown that compared with BRPS and EffiCuts, the proposed algorithm not only improves the time and space performance, but also greatly increases the update speed.

• Restorative Dentistry and Endodontics
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• v.49 no.2
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• pp.14.1-14.13
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• 2024

This study aimed to answer the question through a systematic review: Can carbamide peroxide be as effective as hydrogen peroxide and cause less in-office bleaching sensitivity? A literature survey was performed in PubMed/MEDLINE, Embase, Scopus, ISI Web of Science, and gray literature. Primary clinical trials that compared the efficacy or the in-office bleaching sensitivity between carbamide and hydrogen peroxides were included. The risk of bias was evaluated using the RoB2. The certainty of the evidence was assessed using the GRADE approach. DPI training significantly improved the mean scores of the dental undergraduates from 7.53 in the pre-DPI-training test to 9.01 in the post-DPI-training test (p < 0.001). After 6 weeks, the mean scores decreased marginally to 8.87 in the retention test (p = 0.563). DPI training increased their confidence level from 5.68 pre-DPI training to 7.09 post-DPI training. The limited evidence suggests that the 37% carbamide peroxide may be similarly effective to the 35% hydrogen peroxide for bleaching teeth in-office and causes less bleaching sensitivity. However, more well-designed split-mouth clinical trials are necessary to strengthen the evidence.

• Tunnel and Underground Space
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• v.34 no.5
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• pp.421-432
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• 2024

Pre-fracturing, a type of pre-conditioning blast, is a method used to weaken rock masses prior to mechanical excavation. In this study, various laboratory tests were conducted on rock core samples obtained from the field to verify the effectiveness of pre-fracturing in controlling the BIDZ (Blast-Induced Damaged Zone) by measuring the physical properties of rock cores obtained from a test site and assessing changes in these properties. In the EDZ (Excavation Damaged Zone) caused by combined excavation using blasting and mechanical excavation, the effect of blasting is generally more significant than that of mechanical excavation, so BIDZ control directly leads to EDZ control. In terms of Poisson's ratio, elastic wave velocity, porosity, density, thermal conductivity, tensile strength and hydraulic conductivity, the BIDZ size in pre-fracturing was smaller than that of conventional blasting. However, no clear reduction in the BIDZ was observed in the case of Young's modulus and uniaxial compressive strength. By applying a theoretical formula predicting the range of tensile cracks caused by blasting and comparing it with the laboratory results, the BIDZ was reasonably predicted. Nonetheless, limitations in accurately predicting BIDZ size were identified due to assumptions regarding ground conditions and charge density in the formula.

• Geomechanics and Engineering
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• v.29 no.2
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• pp.99-111
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• 2022

Instability of bolted rock mass has been a major hazard in the underground coal mining industry for decades. Developing effective support guidelines requires understanding of complex bolted rock mass failure mechanisms. In this study, the dynamic failure behavior, mechanical behavior, and energy evolution of a laboratory-scale bolted specimens is studied by conducting laboratory static-dynamic coupled loading tests. The results showed that: (1) Under static-dynamic coupled loading, the stress-strain curve of the bolted rock mass has a significant impact velocity (strain rate) correlation, and the stress-strain curve shows rebound characteristics after the peak; (2) There is a critical strain rate in a rock mass under static-dynamic coupled loading, and it decreases exponentially with increasing pre-static load level. Bolting can significantly improve the critical strain rate of a rock mass; (3) Compared with a no-bolt rock mass, the dissipation energy ratio of the bolted rock mass decreases exponentially with increasing pre-static load level, the ultimate dynamic impact energy and dissipation energy of the bolted rock mass increase significantly, and the increasing index of the ratio of dissipation energy increases linearly with the pre-static load; (4) Based on laboratory testing and on-site microseismic and stress monitoring, a design method is proposed for a roadway bolt support against dynamic load disturbance, which provides guidance for the design of deep underground roadway anchorage supports. The research results provide new ideas for explaining the failure behavior of anchorage supports and adopting reasonable design and construction practices.

• Journal of Dental Anesthesia and Pain Medicine
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• v.24 no.2
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• pp.91-99
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• 2024

Background: Palatal injections are often painful. We aimed to compare topical ice and 20% benzocaine gel for pre-injection anesthesia before greater palatine nerve block (GPNB) injections. Methods: A randomized split-mouth clinical trial was conducted among patients aged 15-60-years needing bilateral GPNB injections. A total of 120 palatal sites from 60 patients were randomly allocated to Group A (topical ice) or Group B (20% benzocaine gel). Pain was evaluated using sound, eye, motor (SEM), and the visual analog scale (VAS) in both groups. Inferential analysis was performed using the Mann-Whitney U test. Results: The mean age of the participants was 20.5 ± 3.9 years. The median VAS score for group A was 11 (Q1 - Q3: 5.25 - 21.75), which was slightly higher than the 10 (Q1 - Q3: 4.0 - 26.75) reported in group B. However, the difference was not statistically significant (P = 0.955). The median SEM score for group A and group B was 3.5 (Q1 - Q3: 3.0 - 4.0) and 4.0 (Q1 - Q3: 3.0 - 4.0), respectively, which was statistically insignificant (P = 0.869). Conclusion: Using ice as a form of topical anesthetic for achieving pre-injection anesthesia before GPNB was as effective as 20% benzocaine gel.

• Korean Journal of Child Studies
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• v.22 no.1
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• pp.163-175
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• 2001

This study investigated the effect on children's literacy of teacher-child discussion about the contents of storybooks. The subjects were 10 experimental and 10 control 5-year-old kindergarten children in Cheongju. The experimental design was the Split Plot design. The research instruments used for pre- and post-tests were the Vocabulary Decoding Competence Test(Lee, 1998), Writing Competence Test(Lee & Lee, 1990), Story Comprehension Competence Test(Lee, 1998; Morrow, 1990), and the Emergent Reading Ability Judgements for Favorite Storybooks(Sulzby, 1985). Data were analyzed by ANOVA with repeated measures. Results showed that the teacher-child discussions about the contents of storybooks were effective for improving children's competence in decoding vocabulary, writing, and story comprehension but not for improving emergent reading ability.