Early Recognition of Pediatric Strokes in the Emergency Department: Epidemiology, Clinical Presentation, and Factors Impeding Stroke Diagnosis in Children

Si Qi Tan(Si Qi Tan),Wen Qi Cher(Wen Qi Cher),Shu-Ling Chong(Shu-Ling Chong),Angelina Su Yin Ang(Angelina Su Yin Ang ),Sashikumar Ganapathy(Sashikumar Ganapathy ),Derrick Wei Shih Chan(Derrick Wei Shi 대한소아신경학회 2022 대한소아신경학회지 Vol.31 No.1

Purpose: Strokes are challenging to diagnose in pediatric emergency departments (EDs) as level of suspicion is low and atypical presentations are common. We analyzed clinical features, epidemiology and factors of delayed identification in arterial ischemic strokes (AIS) and hemorrhagic strokes (HS). Methods: Single-center retrospective cohort study of children aged between 29 days and 18 years old diagnosed with stroke between July 2016 to June 2021. Results: Among 36 children, 11 (30.5%) had AIS, 25 (69.4%) had HS. Median age for AIS was 9 years (interquartile range [IQR], 2 to 9) and HS 9 years (IQR, 1 to 11.5) (P=0.715). Focal neurological deficit was seen in 72.7% of AIS and 20% of HS (P=0.006). Only 18.2% of AIS and 52.0% of HS presented within 6 hours of symptoms. Median time from symptom onset to ED presentation was 24 hours (IQR, 12 to 28) for AIS and 7 hours (IQR, 1.8 to 48) for HS (P=0.595). Most (85.6%) arrived by own transport. Median time from presentation to neuroimaging was 7 hours (IQR, 0.9 to 7) for AIS and 4.8 (IQR, 1.3 to 16.8) hours for HS (P=0.376). Eleven patients, 9/25 (36.0%) HS and 2/11 (18.2%) AIS, did not have stroke as differential diagnosis at ED (P=0.714). Common initial diagnoses were viral illness or headaches. On univariate analysis, age <1 (odds ratio [OR], 17.5; 95% confidence interval [CI], 1.2 to 250.4; P=0.035) and absence of focal neurological deficit (OR, 13.091; 95% CI, 1.5 to 117.9; P=0.022) were significant factors for delayed identification. Conclusion: Index of suspicion for pediatric strokes among caregivers and clinicians should be increased. Public awareness campaigns are recommended.

The earliest timing of ultrasound in screening for developmental dysplasia of the hips

Si Heng Sharon Tan,Keng Lin Wong,Andrew Kean Seng Lim,James HoiPo Hui 대한초음파의학회 2019 ULTRASONOGRAPHY Vol.38 No.4

Purpose: The current study aimed to evaluate the results of ultrasound screening for developmental dysplasia of the hips (DDH) done at various weeks of life, to determine the earliest time that ultrasound screening can be performed reliably. Methods: In this 17-year cohort study, all neonates who underwent ultrasound screening prior to the 12th week of life with subsequent follow-up radiography done at 1 year of life were included. The ultrasound images were evaluated according to the Graf classification, Harcke’s dynamic ultrasound screening method, and Terjesen’s femoral head coverage method. The radiographic images were evaluated according to the acetabular index and the femoral head position. The accuracy and correlation between the ultrasound findings from various weeks of life with the radiographic findings at 1 year of life were evaluated. Results: A total of 348 neonates were included in the study, of whom 92 had abnormal ultrasound findings and 42 had abnormal radiographic findings at 1 year. Significant differences were identified between the findings of ultrasound screening examinations performed prior to the fourth week of life (day 21 and before) and the radiographic findings at 1 year of life (P<0.05). In contrast, no significant differences were identified when ultrasound screening was performed between the fourth and 12th weeks of life (day 22 and beyond) (P>0.05). The accuracy of ultrasound screening was 79.2% or higher when performed during or after the fourth week of life (day 22 and beyond). Conclusion: The earliest that ultrasound screening for DDH can be performed reliably is during the fourth week of life (day 22 and beyond).

Effects of air-impingement jet drying on drying kinetics and quality retention of tomato slices

Si Tan,Yiwen Miao,Hongxia Xiang,Weihua Tan,Wenfeng Li 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.5

The purpose was to explore the drying kinetics,the moisture effective diffusivities, color, total polyphenols,lycopene and antioxidant activities of dried tomatoslices by air-impingement jet drying (AIJD). The resultsshowed that high temperature increased the drying rate, andModified Page model accurately predicted the AIJD characteristicsof tomato slices. AIJD is better than hot airdrying in shortening drying time, enhancing drying rate anddecreasing the loss of total polyphenols, lycopene andantioxidant capacity of tomato slices. Tomato slices driedby AIJD also showed higher lightness and redness. Lycopenecontent and antioxidant activity of tomato slices driedby AIJD were increased by higher drying temperature. Based on experimental data, AIJD at 80 C can be used intomato drying process due to the advantages in dryingefficiency and content of bioactive compounds. This studywill provide helpful information for the production of highquality of dried tomato products.

Effects of three drying methods on polyphenol composition and antioxidant activities of Litchi chinensis Sonn.

Si Tan,Jianmin Tang,Wenjing Shi,Zhuwei Wang,Yuanyuan Xiang,Tingwei Deng,Xiaoxu Gao,Wenfeng Li,Shengyou Shi 한국식품과학회 2020 Food Science and Biotechnology Vol.29 No.3

The aim of this study was to investigate the effects of three different drying methods, freeze drying (FD), vacuum drying (VD) and oven drying (OD) on phenolic contents and antioxidant activities of litchi fruits. 20 polyphenols were exactly identified in the litchi fruits by UPLC-QqQ/MS. Significant losses were observed in the contents of total polyphenols and antioxidant activities in the dried litchi when compared with the fresh litchi. Principle component analysis indicated that there was significant difference of phenolic component between the use of thermal drying (VD and OD) and FD. Our results suggest that FD is the optimum drying method for litchi fruits considering the content of total polyphenols and antioxidant activities.

Correlations between ultrasonographic and subsequent radiographic findings of developmental dysplasia of the hips

Si Heng Sharon Tan,Cheng Han Wu,Keng Lin Wong,James HoiPo Hui 대한초음파의학회 2020 ULTRASONOGRAPHY Vol.39 No.1

Purpose: The study aimed to investigate the utility of ultrasonographic (US) findings in predicting the subsequent radiographic parameters of developmental dysplasia of the hips. Methods: In this 12-year retrospective cohort study, all new-born infants with a positive clinical examination or risk factors were included. They were scheduled for hip ultrasonography in the first 3 months, and subsequent radiographs at 1 year of life. The US images were evaluated using the Graf classification, Harcke’s dynamic screening method, and Terjesen’s femoral head coverage method. The radiographic images were evaluated using the acetabular index and femoral head position. The overall US or radiographic findings were considered abnormal if they were classified as abnormal for any of their respective parameters. The overall US and radiographic parameters were correlated. Results: A total of 160 patients were included. The overall US and radiographic parameters showed no statistically significant difference (P=0.050). The sensitivity, specificity, and accuracy of the overall US parameters were 57.1%, 84.9%, and 81.3%, respectively. All three individual US parameters showed no statistically significant differences, with the overall radiographic findings and acetabular index (P>0.05). However, they showed a statistically significant difference, with the position of the femoral head (P<0.001), with the US parameters having an excellent negative predictive value of 100% for identifying an abnormal femoral head position. Conclusion: The current study suggests that US findings evaluated in the first 3 months of life showed no statistically significant difference with radiographic findings evaluated at 1 year of life. The US parameters showed an excellent negative predictive value for abnormal femoral head position on radiographs

Drying kinetics and physicochemical properties of kumquat under hot air and air-impingement jet dryings

Si Tan,Yu Wang,Wenwen Fu,Yuping Luo,Shan Cheng,Wenfeng Li 한국식품과학회 2022 Food Science and Biotechnology Vol.31 No.6

Kumquat is famous for its unique flavor and nutritional value. In this study, the drying kinetics, moisture effective diffusivity, phytochemical properties, and antioxidant capacities of kumquat dried by hot air drying (HAD) and air-impingement jet drying (AIJD) were comparatively investigated. The results showed that drying rate, moisture effective diffusivity, and nutrient retention under AIJD were better than those under HAD. Fourteen polyphenols were identified by UPLC-QqQ-MS/MS in kumquat slices. The content of limonoid was significantly increased after AIJD. It was also found that high temperature contributed to a higher drying rate. However, most of the polyphenol components decreased at high drying temperatures. Accordingly, AIJD 60 °C was regarded as the optimum condition for kumquat drying. This work contributed to a better understanding of the drying character of kumquat under AIJD and showed the bioactive compounds and antioxidant activities are affected by drying methods.

Effect of Hot-zone Aperture on the Growth Behavior of SiC Single Crystal Produced via Top-seeded Solution Growth Method

Ha, Minh-Tan,Shin, Yun-Ji,Bae, Si-Young,Park, Sun-Young,Jeong, Seong-Min The Korean Ceramic Society 2019 한국세라믹학회지 Vol.56 No.6

The top-seeded solution growth (TSSG) method is an effective approach for the growth of high-quality SiC single crystals. In this method, the temperature gradient in the melt is the key factor determining the crystal growth rate and crystal quality. In this study, the effects of the aperture at the top of the hot-zone on the growth of the SiC single crystal obtained using the TSSG method were evaluated using multiphysics simulations. The temperature distribution and C concentration profile in the Si melt were taken into consideration. The simulation results showed that the adjustment of the aperture at the top of the hot-zone and the temperature gradient in the melt could be finely controlled. The surface morphology, crystal quality, and polytype stability of the grown SiC crystals were investigated using optical microscopy, high-resolution X-ray diffraction, and micro-Raman spectroscopy, respectively. The simulation and experimental results suggested that a small temperature gradient at the crystal-melt interface is suitable for growing high-quality SiC single crystals via the TSSG method.

Hyperglycemia-Associated Hemichorea-Hemiballismus with Predominant Ipsilateral Putaminal Abnormality on Neuroimaging

Si Lei Fong,Ai Huey Tan,Kar Foo Lau,Norlisah Ramli,Shen-Yang LIM 대한파킨슨병및이상운동질환학회 2019 Journal Of Movement Disorders Vol.12 No.3

Hemichorea-hemiballismus is characterized by unilateral, brief, unpredictable involuntary movements of one side of the body (upper and lower limbs and sometimes also affecting the face). The most common causes for this condition are strokes, hyperglycemia-associated hemichorea-hemiballismus, and other focal lesions affecting the basal ganglia

Explicit Dynamic Coordination Reinforcement Learning Based on Utility

Huaiwei Si,Guozhen Tan,Yifu Yuan,Yanfei peng,Jianping Li 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.3

Multi-agent systems often need to achieve the goal of learning more effectively for a task through coordination. Although the introduction of deep learning has addressed the state space problems, multi-agent learning remains infeasible because of the joint action spaces. Large-scale joint action spaces can be sparse according to implicit or explicit coordination structure, which can ensure reasonable coordination action through the coordination structure. In general, the multi-agent system is dynamic, which makes the relations among agents and the coordination structure are dynamic. Therefore, the explicit coordination structure can better represent the coordinative relationship among agents and achieve better coordination between agents. Inspired by the maximization of social group utility, we dynamically construct a factor graph as an explicit coordination structure to express the coordinative relationship according to the utility among agents and estimate the joint action values based on the local utility transfer among factor graphs. We present the application of such techniques in the scenario of multiple intelligent vehicle systems, where state space and action space are a problem and have too many interactions among agents. The results on the multiple intelligent vehicle systems demonstrate the efficiency and effectiveness of our proposed methods.

Research on Service Component Retrieval with Hadoop

Wen Si,Rong Tan,Lu Bing 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.10

It remains both important and difficult for service-oriented computing to retrieve accurately and efficiently the service components fulfilling the client’s need. This paper intends to present a method for use in retrieving the personalized service components based on Hadoop architecture. It extends the semantic ontology of service components, and proposes the methods for building and inquiring the index files based on Lucene. By utilizing the HDFS and adopting the QoS computation and personalized recommendation techniques, the working principles of Map and Reduce of Hadoop are expanded. Experiment results show that the proposed method is applicable in realizing the retrieval of service components in distributed computing environment.