963 results on '"Hyun-Jin Park"'
Search Results
252. Plaque Removal Effectiveness of 3D Printed Dental Hygiene Chews with Various Infill Structures Through Artificial Dog Teeth
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Su Hyun Lee, Hyun Woo Kim, and Hyun Jin Park
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History ,Multidisciplinary ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Abstract
Pet food has recently been in the spotlight as an auxiliary approach to manage oral health, since it helps dogs or cats to take relatively simple care of their mouths at home. Especially, dental hygiene chew is crucial to remove teeth accumulation or plaque by chemical or mechanical methods. This study applied 3D printing to dental chews, which should be tailored to dogs' individual tooth structure and preferences. The optimum methods for making dental hygiene chews based on corn starch with glycerin for extrusion-based 3D printing were developed. The viscoelasticity of dental chews increased with increasing glycerin content. According to the infill level (40%, 60%, or 80%) and glycerin content, texture and plaque removal efficacy were investigated using a texture analyzer and dog dentures. A 60% infill level with 10% and 20% glycerin content had the best plaque removal efficacy in both canines and premolars. A lattice structure design with square holes was more effective for canines, whereas a crumbly texture was more effective for premolars.
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- 2021
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253. Measurement of the inner structure of turbidity currents by ultrasound velocity profiling
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Yasushi Takeda, Yuichi Murai, Yuji Tasaka, Shun Nomura, Hyun Jin Park, Giovanni De Cesare, Jumpei Hitomi, and Hide Sakaguchi
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Materials science ,Turbidity current ,Two-fluid model ,General Physics and Astronomy ,02 engineering and technology ,01 natural sciences ,010305 fluids & plasmas ,symbols.namesake ,0203 mechanical engineering ,0103 physical sciences ,Flume experiment ,Ultrasound Doppler velocity profiling ,Fluid Flow and Transfer Processes ,Mechanical Engineering ,Mechanics ,Shear (sheet metal) ,Flume ,020303 mechanical engineering & transports ,Amplitude ,symbols ,Particle ,Body region ,Current (fluid) ,Velocity field ,Doppler effect - Abstract
The inner velocity structure and particle concentration profile of opaque turbidity currents were measured simultaneously by ultrasound velocity profilers. Currents consisting of a quartz particle suspension were generated by using the lock-exchange method in a flume to experimentally reproduce the quasi-steady state of a turbidity current. A pair of ultrasound transducers captured the horizontal and vertical velocities from Doppler frequencies, and the particle concentration profile was extracted from the echo amplitude. The data obtained were analyzed in terms of momentum conservation according to the two-fluid model. We found that: i) the viscous and Reynolds shear stresses balance in the top half of the current; and ii) the lower border of the stress balancing appears around the depth of the maximum vertical density gradient. These findings indicate that the reduction of flow resistance inside the body region of the turbidity current is maintained downstream, which enables the current to transport particles over a long distance., International Journal of Multiphase Flow, 136, ISSN:0301-9322, ISSN:1879-3533
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- 2021
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254. Favorable outcome of highdose chemotherapy and autologous hematopoietic stem cell transplantation in patients with nonmetastatic osteosarcoma and lowdegree necrosis.
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Kyung Taek Hong, Hyun Jin Park, Bo Kyung Kim, Hong Yul An, Jung Yoon Choi, Jung-Eun Cheon, Sung-Hye Park, Han-Soo Kim, and Hyoung Jin Kang
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HEMATOPOIETIC stem cell transplantation ,TREATMENT effectiveness ,NEOADJUVANT chemotherapy ,NECROSIS ,CANCER chemotherapy - Abstract
Background: A low-degree tumor necrosis after neoadjuvant chemotherapy is a poor prognostic factor for osteosarcoma (OSA). However, the role of highdose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation in OSA remains controversial. We analyzed the treatment outcomes and prognostic factors of nonmetastatic OSA and compared the HDC and conventional chemotherapy (CC) outcomes of patients with <90% necrosis after neoadjuvant chemotherapy. Methods: We retrospectively evaluated patients with OSA treated at the Seoul National University Children's Hospital from 2000 to 2020. Totally, 113 patients with non-metastatic OSA at diagnosis were included. The majority were treated with cisplatin, doxorubicin, and methotrexate as neoadjuvant chemotherapy. This was continued when the postoperative necrosis rate was >90% (good response [GR]), whereas most cases with <90% (poor response [PR]) were changed to chemotherapy. The HDC regimen was composed of melphalan, etoposide, and carboplatin. Results: The median age at diagnosis was 12.6 years (range, 5.0-20.3), and 61.9% of patients were men. The 5-year event-free survival (EFS) and overall survival (OS) rates were 75.8% and 91.5%, respectively. Among these, 59 and 44 patients were included in the GR and PR groups, respectively. The GR group had a better 5-year EFS rate than the PR group (82.4% vs. 67.3%, p=0.071). Age at diagnosis, sex, tumor site, type of neoadjuvant chemotherapy, and degree of tumor necrosis were not different between the PR-HDC (n=24) and PR-CC (n=20) groups. The 5-year EFS and OS rates in the PR-HDC (n=24) and PR-CC (n=20) groups were 78.6% and 53.6% (p=0.065) and 100% and 76.9% (p=0.024), respectively. In the Cox regression analysis, the PR-CC group (hazard ratio, 4.95; p=0.004) and age =12 years (hazard ratio, 2.68; p=0.024) were significant risk factors for 5-year EFS. Conclusions: HDC showed favorable outcomes in patients with nonmetastatic OSA and <90% necrosis after neoadjuvant chemotherapy. [ABSTRACT FROM AUTHOR]
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- 2022
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255. Clinical outcome of biportal endoscopic revisional lumbar discectomy for recurrent lumbar disc herniation
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Dae-Jung Choi, Jin Ho Hwang, Hyun-Jin Park, Min-Seok Kang, Hyong Nyun Kim, Hoon-Jae Chung, and Jong-Hwa Lee
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Adult ,Male ,Reoperation ,medicine.medical_specialty ,Nerve root ,Visual analogue scale ,Lumbosacral radiculopathy ,03 medical and health sciences ,0302 clinical medicine ,Patient satisfaction ,Recurrence ,Technical Note ,Revisional lumbar discectomy ,medicine ,Humans ,Orthopedics and Sports Medicine ,Retrospective Studies ,030222 orthopedics ,Lumbar Vertebrae ,business.industry ,Biportal endoscopic ,Soft tissue ,Endoscopy ,Retrospective cohort study ,Perioperative ,Middle Aged ,Open microscopic ,Surgery ,Treatment Outcome ,Recurrent lumbar disc herniation ,Orthopedic surgery ,Feasibility Studies ,Female ,business ,Intervertebral Disc Displacement ,030217 neurology & neurosurgery ,Diskectomy - Abstract
Background Although literature provides evidence regarding the superiority of surgery over conservative treatment in patients with lumbar disc herniation, recurrent lumbar disc herniation (RLDH) was the indication for reoperation in 62% of the cases. The major problem with revisional lumbar discectomy (RLD) is that the epidural scar tissue is not clearly isolated from the boundaries of the dura matter and nerve roots; therefore, unintended durotomy and nerve root injury may occur. The biportal endoscopic (BE) technique is a newly emerging minimally invasive spine surgical modality. However, clinical evidence regarding BE-RLD remains limited. We aimed to compare the clinical outcomes after performing open microscopic (OM)-RLD and BE-RLD to evaluate the feasibility of BE-RLD. Methods This retrospective study included 36 patients who were diagnosed with RLDH and underwent OM-RLD and BE-RLD. RLDH is defined as the presence of herniated disc material at the level previously operated upon in patients who have experienced a pain-free phase for more than 6 months. BE-RLD was performed as follows: two independent surgical ports were made inside the medial pedicular line of the target segment and on the intact upper and lower laminas. Peeling off the soft tissue from the vertebral lamina helps to easily identify the traversing nerve root and the recurrent disc material without dealing with the fibrotic scar tissue. Clinical outcomes were obtained using a visual analog scale (VAS) and the modified Macnab criteria before and at 2 days, 2 and 6 weeks, and 3, 6, and 12 months after surgery. Results The data of 20 and 16 patients who underwent OM-RLD and BE-RLD, respectively, were evaluated. The demographic and perioperative data were comparable between the groups. During the year following the surgery, in the BE-RLD group, the VAS scores at each point were significantly improved over the baseline and remained improved up to 2 weeks after surgery (p < 0.05); however, no statistical difference between the two groups was observed after 6 weeks of surgery (p > 0.05). According to the modified Macnab criteria on the follow-up, the excellent or good satisfaction rates reported at 2 weeks, 6 weeks, 6 months, and 12 months after surgery were 81.25%, 81.25%, 75%, and 81.25%, respectively, in the BE-RLD group, and 50%, 75%, 75%, and 80%, respectively, in the OM-RLD group. Conclusion BE-RLD yielded similar outcomes to OM-RLD, including pain improvement, functional improvement, and patient satisfaction, at 1 year after surgery. However, faster pain relief, earlier functional recovery, and better patient satisfaction were observed when applying BE-LRD. Trial registration Retrospectively registered
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- 2020
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256. Small Footprint Multi-channel Keyword Spotting
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Hyun-Jin Park, Niranjan Subrahmanya, Jilong Wu, Yiteng Huang, and Patrick Violette
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Computer science ,Small footprint ,Keyword spotting ,Data mining ,computer.software_genre ,computer ,Multi channel - Published
- 2020
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257. Kappa-Carrageenan-Based Dual Crosslinkable Bioink for Extrusion Type Bioprinting
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Min-Young Lee, Jae Min Cha, Jeong Wook Seo, Hojae Bae, Jiyeon Lee, Seon Young Shin, Su Ryon Shin, Xiaowei Zhang, Hyun Jin Park, Hyunwoo Kim, Wonseop Lim, Gyeong Jin Kim, and Min Gyeong Kang
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3D bioprinting ,Materials science ,Polymers and Plastics ,Kappa-Carrageenan ,Biocompatibility ,0206 medical engineering ,Nanotechnology ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Article ,law.invention ,lcsh:QD241-441 ,Viscosity ,kappa-carrageenan ,Rheology ,lcsh:Organic chemistry ,law ,methacrylic anhydride ,Extrusion ,0210 nano-technology ,dual crosslinking hydrogel - Abstract
Bioink based 3D bioprinting is a promising new technology that enables fabrication of complex tissue structures with living cells. The printability of the bioink depends on the physical properties such as viscosity. However, the high viscosity bioink puts shear stress on the cells and low viscosity bioink cannot maintain complex tissue structure firmly after the printing. In this work, we applied dual crosslinkable bioink using Kappa-carrageenan (&kappa, CA) to overcome existing shortcomings. &kappa, CA has properties such as biocompatibility, biodegradability, shear-thinning and ionic gelation but the difficulty of controlling gelation properties makes it unsuitable for application in 3D bioprinting. This problem was solved by synthesizing methacrylated Kappa-carrageenan (MA-&kappa, CA), which can be dual crosslinked through ionic and UV (Ultraviolet) crosslinking to form hydrogel using NIH-3T3 cells. Through MA substitutions, the rheological properties of the gel could be controlled to reduce the shear stress. Moreover, bioprinting using the cell-laden MA-&kappa, CA showed cell compatibility with enhanced shape retention capability. The potential to control the physical properties through dual crosslinking of MA-&kappa, CA hydrogel is expected to be widely applied in 3D bioprinting applications.
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- 2020
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258. Safety Evaluation of Biportal Endoscopic Lumbar Discectomy: Assessment of Cervical Epidural Pressure During Surgery
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Min-Seok Kang, Jin Ho Hwang, Ju-Eun Kim, Hyun-Jin Park, Dae-Jung Choi, and Hoon-Jae Chung
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Adult ,Epidural Space ,Male ,medicine.medical_specialty ,Percutaneous ,Decompression ,medicine.medical_treatment ,Therapeutic irrigation ,Neurosurgical Procedures ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Spinal Stenosis ,Discectomy ,medicine ,Pressure ,Humans ,Orthopedics and Sports Medicine ,Spinal canal ,Diskectomy, Percutaneous ,Prospective Studies ,Prospective cohort study ,Therapeutic Irrigation ,Intracranial pressure ,Aged ,030222 orthopedics ,Lumbar Vertebrae ,business.industry ,Endoscopy ,Middle Aged ,Decompression, Surgical ,Surgery ,medicine.anatomical_structure ,Treatment Outcome ,Female ,Neurology (clinical) ,Thecal sac ,Safety ,business ,030217 neurology & neurosurgery ,Neck ,Diskectomy - Abstract
Study design A prospective study. Objective To evaluate the change in cervical epidural pressure (CEP) during biportal endoscopic lumbar discectomy (BELD). Summary of background data In percutaneous uniportal endoscopic lumbar discectomy, irrigation fluid (IF) introduced into the spinal canal during surgery can compress the thecal sac, and act as a potential risk for neurological complications by disturbing cerebrospinal fluid (CSF) circulation and increasing intracranial pressure. Methods Thirty consecutive patients, who underwent BELD, which was performed under automated pump system, an infusion pressure of 30 mmHg were enrolled. The change in CEP on C7-T1 level was measured. CEP was measured in each of the five phases of the procedure (1st phase-making surgical portals; 2nd phase-creating a workspace; 3rd phase-performing neural decompression and discectomy; 4th phase-factitious increase of pressure by clogging the outflow; 5th phase-dismission from fluid irrigation system). Neurological complications and independent risk factors were evaluated. Results In the final 27 patients, changes in CEP during surgery were similar. The baseline CEP was 14.8 ± 2.8 mmHg, and the mean CEP in the 3rd phase 18.8 ± 5.1 mmHg was not significantly higher. In the 4th phase, however, the CEPs rose with linear correlation as the pressure increased. In the 5th phase, the elevated CEP returned to baseline in 2.5 ± 5.6 minutes. No patient had neurological complications. No statistically significant risk factors were observed. Conclusion In BELD, which is performed to allow continuous lavage with infusion pressure set to 30 mmHg, CEP does not increase beyond the physiological range. Therefore, BELD may be considered as a potentially safe technique. Level of evidence 4.
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- 2020
259. Detailed analysis of phenotypes and genotypes in megalencephaly-capillary malformation-polymicrogyria syndrome caused by somatic mosaicism of PIK3CA mutations
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Man Jin Kim, Moon Woo Seong, Chang Ho Shin, Tae Joon Cho, Hyun Jin Park, Jung Min Ko, Won Joon Yoo, Sung Sup Park, Jeong Ho Lee, and Nam Suk Sim
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0301 basic medicine ,Hemimegalencephaly ,Pathology ,medicine.medical_specialty ,Cutaneous vascular malformation ,Genotype ,Class I Phosphatidylinositol 3-Kinases ,Genetic counseling ,lcsh:Medicine ,030105 genetics & heredity ,03 medical and health sciences ,0302 clinical medicine ,Republic of Korea ,medicine ,Polymicrogyria ,Humans ,Pharmacology (medical) ,Megalencephaly ,Genetics (clinical) ,Genetic testing ,medicine.diagnostic_test ,Mosaicism ,business.industry ,Research ,lcsh:R ,Vascular malformation ,Macrocephaly ,Asymmetry ,PIK3CA ,General Medicine ,medicine.disease ,Phenotype ,Mutation ,Somatic overgrowth ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
Background Megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP) belongs to a group of conditions called the PIK3CA-related overgrowth spectrum (PROS). The varying phenotypes and low frequencies of each somatic mosaic variant make confirmative diagnosis difficult. We present 12 patients who were diagnosed clinically and genetically with MCAP. Genomic DNA was extracted mainly from the skin of affected lesions, also from peripheral blood leukocytes and buccal epithelial cells, and target panel sequencing using high-depth next-generation sequencing technology was performed. Results Macrocephaly was present in 11/12 patients (92%). All patients had normal body asymmetry. Cutaneous vascular malformation was found in 10/12 patients (83%). Megalencephaly or hemimegalencephaly was noted in all 11 patients who underwent brain magnetic resonance imaging. Arnold–Chiari type I malformation was also seen in 10 patients. Every patient was identified as having pathogenic or likely pathogenic variants of the PIK3CA gene. The variant allele frequency (VAF) ranged from 6.3 to 35.3%, however, there was no direct correlation between VAF and the severity of associated anomalies. c.2740G > A (p.Gly914Arg) was most commonly found, in four patients (33%). No malignancies developed during follow-up periods. Conclusions This is the first and largest cohort of molecularly diagnosed patients with MCAP in Korea. Targeted therapy with a PI3K-specific inhibitor, alpelisib, has shown successful outcomes in patients with PROS in a pilot clinical study, so early diagnosis for genetic counseling and timely introduction of emerging treatments might be achieved in the future through optimal genetic testing.
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- 2020
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260. Rice straw cover decreases soil erosion and sediment-bound C, N, and P losses but increases dissolved organic C export from upland maize fields as evidenced by δ
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Se-In, Park, Hye In, Yang, Hyun-Jin, Park, Bo-Seong, Seo, Young-Jae, Jeong, Sang-Sun, Lim, Jin-Hyeob, Kwak, Han-Yong, Kim, Kwang-Sik, Yoon, Sang-Mo, Lee, and Woo-Jung, Choi
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Soil ,Agriculture ,Oryza ,Phosphorus ,Zea mays - Abstract
Soil surface with crop residue is effective in reducing soil erosion and carbon (C), nitrogen (N), and phosphorus (P) losses from sloping fields. However, there is a high possibility that surface cover increases export of dissolved organic C (DOC) though relevant field studies under natural rainfall are lacking. In this study, the effects of surface cover with rice (Oryza sativa L.) straw on soil and CNP losses in both dissolved and sediment-bound forms from maize (Zea mays L.) fields were investigated under two fertilization levels (standard and double) × two types of runoff experiments (natural rainfall and artificial irrigation). Changes in soil properties including moisture, temperature, nutrients, and C concentration as well as maize yield were also examined. Surface cover decreased soil and total CNP losses by up to 82% across the experimental plots with some exceptions. However, surface cover increased DOC export in both natural (by 68-82% in total across all events) and artificial (by 3-4 fold) runoff, suggesting that crop residue cover may act as a DOC pollution source of water bodies. The contribution of rice straw to DOC, which was calculated using the δ
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- 2020
261. How I do it? Extraforaminal lumbar interbody fusion assisted with biportal endoscopic technique
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Hyun-Jin Park, Hoon-Jae Chung, Ho-Jung Jung, and Min-Seok Kang
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musculoskeletal diseases ,Male ,medicine.medical_specialty ,Decompression ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Lumbar ,Spinal Stenosis ,Lumbar interbody fusion ,Interbody cage ,medicine ,Humans ,Spinal canal ,Foraminal stenosis ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Interventional radiology ,Endoscopy ,Middle Aged ,Decompression, Surgical ,Posterior arch ,Surgery ,medicine.anatomical_structure ,Spinal Fusion ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
The biportal endoscope-assisted unilateral foraminal approach is an option for various foraminal pathologies. Lumbar interbody fusion is the standard treatment for foraminal stenosis because both direct and indirect neural decompressions can be obtained. We used the biportal endoscopic technique for extraforaminal lumbar interbody fusion (BE-EFLIF) and have described the steps, with discussion regarding the indications, advantages, possible complications, and ways to overcome complications. BE-EFLIF achieves direct neural decompression of lateral spinal canal under endoscopic visualization. It achieves indirect neural decompression using a large footprint lordotic interbody cage, while preserving the lumbar posterior arch as much as possible.
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- 2020
262. 3-D driving mechanism of a Savonius turbine due to twisted buckets
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Yuichi Murai, Toshiki Ashida, Yuji Tasaka, and Hyun Jin Park
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Mechanism (engineering) ,Materials science ,Mechanics ,Turbine - Published
- 2019
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263. Ultrasonic Monitoring of Gas-liquid Two-phase Turbulent Flows
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Yuji Tasaka, Hyun Jin Park, and Yuichi Murai
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Materials science ,Turbulence ,Ultrasonic monitoring ,Phase (matter) ,Mechanics - Published
- 2019
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264. Numerical Simulation on Turbulent Channel Flow for Single Large Bubble near the Wall
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Nobuyuki Oshima, Hyun Jin Park, Sangwon Kim, and Yuichi Murai
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Physics ,Turbulent channel flow ,Computer simulation ,Bubble ,Mechanics - Published
- 2019
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265. Investigation of the moisture-induced caking behavior with various dietary salts
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Min Hyeock Lee, Hyun Jin Park, and Hansol Doh
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chemistry.chemical_classification ,food.ingredient ,Moisture ,Chemistry ,Sea salt ,Sodium ,Moisture sorption isotherm ,Salt (chemistry) ,chemistry.chemical_element ,Sorption ,04 agricultural and veterinary sciences ,040401 food science ,03 medical and health sciences ,0404 agricultural biotechnology ,0302 clinical medicine ,food ,Caking ,Environmental chemistry ,030221 ophthalmology & optometry ,Relative humidity ,Food Science - Abstract
Caking of dietary salt is a well-known problem in food industries. In this study, caking behavior of various kinds of dietary salt, including refined salt, sea salt (from South Korea and France), bamboo salt, rock salt, and sodium chloride (used as control group) was investigated. According to our results, these dietary salts had different mineral content and moisture sorption isotherm. The sea salt had more minerals than the other salts. As a result, the deliquescence relative humidity of the sea salt was significantly lower than that of the other dietary salt, which resulted in higher water sorption ability. After salts were stored in two humidity cycle conditions, the change in moisture content, caking strength, passed ratio, and morphology was determined. In the case of sea salt, the highest caking strength, the lowest passed ratio, and lots of crystal bridges caused by caking were observed.
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- 2019
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266. Dynamic stall controlling of the Darrieus wind turbine using turbo-sail airfoils
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Yuichi Murai, Hyun Jin Park, Yoshimichi Ono, and Yuji Tasaka
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Airfoil ,biology ,Turbo ,Environmental science ,Stall (fluid mechanics) ,biology.organism_classification ,Darrieus wind turbine ,Marine engineering - Published
- 2019
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267. How to Review Postlobectomy Posteroanterior Chest Radiographs
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Hyun Jin Park, Jeong Min Ko, and Min Kyung Jung
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Standard of care ,Radiography ,Critical Care and Intensive Care Medicine ,Malignancy ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,030212 general & internal medicine ,Lung cancer ,Pneumonectomy ,Lung ,medicine.diagnostic_test ,business.industry ,Bronchial stump ,respiratory system ,medicine.disease ,Lobe ,respiratory tract diseases ,medicine.anatomical_structure ,030228 respiratory system ,Plain radiographs ,Radiography, Thoracic ,sense organs ,Radiology ,Cardiology and Cardiovascular Medicine ,Chest radiograph ,business - Abstract
Lung cancer is currently the most common malignancy in the world. A lobectomy is the standard of care for most patients with operable lung cancer and accounts for 60% to 70% of lung resection. The chest radiograph may appear normal after a lobectomy, particularly in uncomplicated cases. However, lobectomy usually involves leaving surgical staples at the bronchial stump and causes various changes in the intra- and extrapulmonary thoracic structures on plain radiographs. These changes may differ according to the resected lobe. We retrospectively evaluated the plain radiographic appearances of the postlobectomy chest, free of postoperative complications or recurrent/metastatic lung cancer. On the basis of our observations, the changes that occur in pulmonary and extrapulmonary anatomy can differ according to the resected lobe. Recognition of these changes will make it easier to identify which lobe has been removed surgically.
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- 2020
268. A multi-responsive biomimetic nano-complex platform for enhanced gene delivery
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Xiaoyu Bai, Chao Feng, Hyun Jin Park, Xiguang Chen, Xuanjin Wu, and Ming Kong
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0301 basic medicine ,Cell ,Biomedical Engineering ,02 engineering and technology ,Gene delivery ,HeLa ,03 medical and health sciences ,chemistry.chemical_compound ,RNA interference ,Hyaluronic acid ,medicine ,Gene silencing ,General Materials Science ,biology ,Chemistry ,technology, industry, and agriculture ,General Chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Cytosol ,030104 developmental biology ,medicine.anatomical_structure ,Biophysics ,0210 nano-technology ,Intracellular - Abstract
RNA interference (RNAi) is widely regarded as a promising technology for disease treatment, yet one major obstacle for its clinical application is the lack of enhanced siRNA delivery vehicles to circumvent complex extra- and intracellular barriers. By integrating unique peculiarities of thioglycolic acid conjugated chitosan nanoparticles (TCS NPs), biomimetic transfersomes (T) and amphiphilic hyaluronic acid (HA-GMS), a novel nano-complex was prepared, where vascular endothelial growth factor (VEGF) siRNA loaded TCS NPs were cloaked by transfersomes with HA-GMS assembled on the surface (HT-TCS-siRNA NPs). The nano-complex provided superior siRNA protection and desirable stability at pH 7.4 and 6.5 (mimicking tumor tissue) and exerted proton sponge effects at acidic pH 5.0 (mimicking endo/lysosomes). The TCS NPs were stable at pH 5.0 but disintegrated in the presence of 10 mM glutathione (GSH) at pH 7.4 (mimicking tumor cytosol), which was favorable to release siRNA to the cytoplasm. In vitro cell uptake and gene silencing assays exhibited enhanced intracellular siRNA accumulation and VEGF silencing efficacy of HT-TCS-siRNA NPs in HeLa cells. The enhanced gene delivery capacity of the multi-responsive biomimetic nano-complex gives them potential for application in cancer therapy.
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- 2020
269. Toxic potential of Bacillus cereus isolated from fermented alcoholic beverages
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Sun Ae Kim, Tae Jin Cho, Hyun Jin Park, and Min Suk Rhee
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030309 nutrition & dietetics ,Bacillus cereus ,Enterotoxin ,Biology ,medicine.disease_cause ,03 medical and health sciences ,chemistry.chemical_compound ,Enterotoxins ,0404 agricultural biotechnology ,Gene cluster ,medicine ,Food science ,Wine ,0303 health sciences ,Toxin ,Alcoholic Beverages ,food and beverages ,04 agricultural and veterinary sciences ,Cereulide ,biology.organism_classification ,Fruit wine ,040401 food science ,Cereus ,chemistry ,Food Microbiology ,Fermented Foods ,Food Science - Abstract
Pathogenicity of Bacillus cereus is associated with the production of various toxins. This study investigated the distribution of toxin genes encoding haemolysin BL (hblA, hblC, and hblD), nonhemolytic enterotoxin (nheA, nheB, and nheC), enterotoxin FM (entFM), cytotoxin K (cytK), and cereulide (ces) in 185 B. cereus strains isolated from draft beer, microbrewed beer, pasteurized beer, grape wine, other fruit wine, refined rice wine, traditional Korean pure liquor, and traditional Korean turbid rice wines. A total of 93.0% (172 isolates) of these isolates possessed at least one toxin gene. The nonhemolytic enterotoxin-encoding genes were highly prevalent in the isolates; the detection rate of enterotoxins was 91.4% for nheC, 81.6% for entFM, 62.7% for nheB, 57.3% for nheA, 53.0% for hblC, 48.6% for cytK, 36.8% for hblA, and 36.2% for hblD. Overall, 54.6% and 33.0% of strains carried the integrated Nhe-encoding gene cluster (nheA, nheB, nheC at the same time) and had the Hbl-encoding gene cluster, respectively. The cereulide synthetase gene was detected in only 2.2% of isolates. Toxin gene distribution patterns could be classified into 8 major profile clusters, and the most prevalent profile was the presence of enterotoxin genes only and no emetic toxin genes. Therefore, B. cereus in fermented alcoholic beverages was predominantly of the diarrhoeagenic type. Our results may provide important basic information when considering microbial standards and regulations for B. cereus in related products.
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- 2020
270. Post-Transplantation Cyclophosphamide-Based Haploidentical versus Matched Unrelated Donor Peripheral Blood Hematopoietic Stem Cell Transplantation Using Myeloablative Targeted Busulfan-Based Conditioning for Pediatric Acute Leukemia
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Kyung Taek Hong, Hyun Jin Park, Bo Kyung Kim, Hong Yul An, Jung Yoon Choi, and Hyoung Jin Kang
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Transplantation ,Adolescent ,Hematopoietic Stem Cell Transplantation ,Cell Biology ,Hematology ,Leukemia, Myeloid, Acute ,Humans ,Molecular Medicine ,Immunology and Allergy ,Child ,Unrelated Donors ,Busulfan ,Cyclophosphamide ,Retrospective Studies - Abstract
The use of haploidentical related donors (HRDs) is a common alternative donor strategy used when matched sibling or unrelated donors are not available for hematopoietic stem cell transplantation (HSCT). However, there have been no studies comparing HRD HSCT with post-transplantation cyclophosphamide (PTCy) and matched unrelated donor (MUD) HSCT with antithymocyte globulin using similar busulfan-based myeloablative conditioning regimens in pediatric acute leukemia. Here we compared the outcomes in children and adolescents with high-risk acute leukemia who underwent HRD HSCT with PTCy (n = 35) or MUD HSCT (n = 45) after targeted busulfan-based myeloablative conditioning using intensive pharmacokinetic monitoring. The median duration of follow-up was 3.7 years in the HRD group and 4.6 years in the MUD group. No engraftment failure was observed in either group. There were no significant between-group differences in the cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) (34.3% versus 48.9%; P = .142), grade III-IV acute GVHD (2.9% versus 8.9%; P = .272), moderate to severe chronic GVHD (11.4% versus 18.3%; P = .417), relapse (25.6% versus 28.0%; P = .832), and nonrelapse mortality (0% versus 2.2%; P = .420). The 3-year severe chronic GVHD-free/relapse-free survival (GRFS), leukemia-free survival (LFS), and overall survival (OS) rates in the HRD and MUD groups were 62.9% (95% confidence interval [CI], 45.8% to 80.0%) versus 49.8% (95% CI, 34.9% to 64.7%; P = .318), 74.4% (95% CI, 58.7% to 90.1%) versus 67.5% (95% CI, 53.4% to 81.6%; P = .585), and 88.6% (95% CI, 78.0% to 99.2%) versus 83.7% (95% CI, 72.5% to 94.9%; P = .968), respectively. In a subgroup analysis of patients with acute lymphoblastic leukemia (HRD, n = 17; MUD, n = 26), the 3-year GRFS, LFS, and OS rates in the HRD and MUD groups were 49.4% (95% CI, 24.3% to 74.5%) versus 39.5% (95% CI, 19.7% to 59.3%; P = .601), 61.8% (95% CI, 37.5% to 86.1%) versus 63.6% (95% CI, 44.4% to 82.8%; P = .872), and 82.4% (95% CI, 64.4%, 100%) versus 84.2% (95% CI, 70.1% to 98.3%; P = .445), respectively. In patients with acute myelogenous leukemia (AML) (HRD, n = 16; MUD, n = 16), the 3-year GRFS, LFS, and OS rates in the HRD and MUD groups were 80.8% (95% CI, 61.2% to 100%) versus 61.9% (95% CI, 37.8% to 86.0%; P = .326), 87.1% (95% CI, 70.2% to 100%) versus 73.9% (95% CI, 51.8% to 96.0%; P = .478), and 93.8% (95% CI, 81.8% to 100%) versus 85.6% (95% CI, 67.0% to 100%; P = .628), respectively. Although the difference was not statistically significant and the number of patients was small, the promising outcomes of HRD HSCT in AML patients were encouraging. Our results demonstrate that HRD HSCT with PTCy using a targeted busulfan-based myeloablative conditioning regimen has outcomes similar to those of MUD HSCT with antithymocyte globulin. HRD HSCT with PTCy could be a feasible option for pediatric high-risk acute leukemia patients who lack an HLA-matched related or unrelated donor.
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- 2022
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271. Drag coefficient of bubbles sliding beneath a towed model ship with variable tilt angles
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Dongik Yoon, Hyun Jin Park, Yuji Tasaka, and Yuichi Murai
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Fluid Flow and Transfer Processes ,Mechanical Engineering ,General Physics and Astronomy - Published
- 2022
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272. Hyaluronic‐Acid‐Coated Chitosan Nanoparticles for Insulin Oral Delivery: Fabrication, Characterization, and Hypoglycemic Ability
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Haishan Wu, Ting Guo, Jian Nan, Liu Yang, Guangfu Liao, Hyun Jin Park, and Jinglei Li
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Chitosan ,Drug Carriers ,Polymers and Plastics ,Mucins ,Administration, Oral ,Bioengineering ,Biomaterials ,Materials Chemistry ,Humans ,Hypoglycemic Agents ,Insulin ,Nanoparticles ,Caco-2 Cells ,Hyaluronic Acid ,Biotechnology - Abstract
Oral administration of insulin faces multiple biological challenges, such as varied digestive environments, mucin exclusion, and low epithelial cells' absorption. In the present study, a hyaluronic acid (HA)-coated chitosan (CS) nanoparticle (HCP) delivery system is fabricated for insulin oral delivery. It is hypothesized that the developed nanoparticles will protect insulin from digestive degradation, promote intestinal epithelial cell absorption, and exert strong in vivo hyperglycemic ability. Nanoparticles formulated by CS and sodium tripolyphosphate (TPP) are optimized to form the core nanoparticles (CNPs). HA is further applied to coat CNP (HCP) to improve stability, reduce enzymatic degradation, and promote absorption of insulin. HCP promotes insulin uptake by Caco-2 cells, absorbs less mucin, and improves intestinal absorption. Moreover, an in vivo test demonstrates that oral administration of insulin-loaded HCP exerts strong and continuous hyperthermia effect (with a pharmacological availability (PA) of 13.8%). In summary, HCP is a promising delivery platform for insulin oral administration in terms of protecting insulin during digestion, facilitating its absorption and ultimately promoting its oral bioavailability.
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- 2022
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273. Comparison of Primary Versus Revision Lumbar Discectomy Using a Biportal Endoscopic Technique
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Min-Seok Kang, Hyun-Jin Park, Ki-Han You, Dae-Jung Choi, Chang-Won Park, and Hoon-Jae Chung
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Orthopedics and Sports Medicine ,Surgery ,Neurology (clinical) - Abstract
Study Design Retrospective study. Objective To compare the clinical outcomes of the biportal endoscopic technique for primary lumbar discectomy (BE-LD) and revision lumbar discectomy (BE-RLD). Methods Eighty-one consecutive patients who underwent BE-LD or BE-RLD, and could be followed up for at least 12 months were divided into two groups: Group A (BE-LD; n = 59) and Group B (BE-RLD; n = 22). Clinical outcomes included the visual analog scale (VAS), Oswestry Disability Index (ODI), and modified MacNab’s criteria. Perioperative results included operation time (OT), length of hospital stay (LOS), amount of surgical drain, and kinetics of serum creatine phosphokinase (CPK) and C-reactive protein (CRP). Clinical and perioperative outcomes were assessed preoperatively and postoperatively at 2 days and at 3, 6, and 12 months. Postoperative complications were noted. Results Both groups showed significant improvement in pain (VAS) and disability (ODI) compared to baseline values at postoperative day 2, which lasted until the final follow-up. There were no significant differences in the improvement of the VAS and ODI scores between the groups. According to the modified MacNab’s criteria, 88.1 and 90.9% of the patients were excellent or good in groups A and B, respectively. OT, LOS, amount of surgical drain, and kinetics in serum CRP and CPK levels were comparable. Complications in Group A included incidental durotomy (n = 2), epidural hematoma (n = 1), and local recurrence (n = 1) and in Group B incidental durotomy (n = 1) and epidural hematoma (n = 1). Conclusion BE-RLD showed favorable clinical outcomes, less postoperative pain, and early laboratory recovery equivalent to BE-LD.
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- 2022
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274. Effects of layered double hydroxides on poly(vinyl alcohol)/poly(acrylic acid) films for green food packaging applications
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Hee Jong Kim, Korakot Charoensri, Jung A. Ko, and Hyun Jin Park
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General Chemical Engineering ,Organic Chemistry ,Materials Chemistry ,Surfaces, Coatings and Films - Published
- 2022
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275. Formulation and evaluation of cold-extruded chocolate ganache for three-dimensional food printing
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Jung Hee Woo, Sun Min Kim, Hyun Jin Park, and Hyunwoo Kim
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Materials science ,Rheology ,Whipped cream ,Food products ,Emulsion ,Food science ,Food Science - Abstract
A novel approach for the production of chocolate ganache that could be cold-extruded using a three-dimensional food printer was proposed herein. To determine the optimal conditions, experiments were performed using various compositional ratios of whipped cream and cocoa powder. Although all whipped cream-based chocolate ganache was cold-extruded, irreversible fat separation occurs with temperature change. Among various whipped cream contents, chocolate ganache with 30% (w/w) whipped cream indicated the highest resolution and was therefore used to investigate the stabilization potential of chocolate ganache. Among various cocoa powder contents, chocolate ganache with 20% (w/w) cocoa powder showed the best results in terms of rheology, emulsion stability, and printing accuracy. We successfully demonstrated that cocoa powder not only increases the load-bearing capacity of chocolate ganache, but also serves as a “Pickering particle”. This system could be applied to materials or other three-dimensionally printed food products that require temperature stabilization.
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- 2022
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276. Effects of Tumor Necrosis Factor-alpha Inhibitors on the Incidence of Tuberculosis
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Nayoung Han, In-Wha Kim, Minji Sohn, Bo Yoon Choi, Hyun Jin Park, and Jung Mi Oh
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medicine.medical_specialty ,Tuberculosis ,business.industry ,Internal medicine ,Incidence (epidemiology) ,Rheumatoid arthritis ,medicine ,Pharmacy ,Tumor necrosis factor alpha ,medicine.disease ,business ,Gastroenterology - Published
- 2018
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277. Effect of Hydrocolloids on Rheological Properties and Printability of Vegetable Inks for 3D Food Printing
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Il Woo Lee, Min Hyeock Lee, Hyunwoo Kim, Jang Ho Lee, Sae Mi Park, Hyun Jin Park, and Hansol Doh
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0301 basic medicine ,Materials science ,Food Handling ,High resolution ,Brassica ,03 medical and health sciences ,0404 agricultural biotechnology ,Rheology ,Spinacia oleracea ,Vegetables ,Confocal laser scanning microscopy ,medicine ,Food material ,Colloids ,Microscopy, Confocal ,030109 nutrition & dietetics ,Polysaccharides, Bacterial ,04 agricultural and veterinary sciences ,040401 food science ,Daucus carota ,Volume (thermodynamics) ,Chemical engineering ,Printing, Three-Dimensional ,Particle ,Ink ,Powders ,Swelling ,medicine.symptom ,Xanthan gum ,Food Science ,medicine.drug - Abstract
In food ink systems in which the particles are dispersed in a hydrocolloid matrix, the source of the particles and the particle content are the main factors affecting the printability and rheological properties of the system. In this study, different contents (10% and 30% w/w) of vegetable (broccoli, spinach, or carrot) powders were added to hydrocolloid matrices with different hydration properties, and their influence on the printability and rheological properties was investigated. At low powder contents (10%), slight differences in the printability and rheological values were observed between the different vegetable sources in all hydrocolloids. When the powder content was increased to 30%, the hydrocolloid with the lowest water hydration capacity, hydroxypropyl methylcellulose, showed the greatest differences in rheology and printability when different vegetable sources were used. Xanthan gum, with its higher water hydration capacity, inhibited the swelling of the particles, thus minimizing the increase in the rheological values at high volume fractions of powder and reducing the differences in printability between different vegetable sources. Confocal laser scanning microscopy analysis of the vegetable inks showed that xanthan gum inhibited swelling of the particles regardless of the vegetable powder source. The mixtures using xanthan gum could be smoothly extruded from the nozzle due to their low extruded hardness (2.96 ± 0.23 to 3.46 ± 0.16 kg), and the resulting objects showed high resolution without collapse over time. PRACTICAL APPLICATION: The powder-based texturization technology introduced in this study provides a standardized method of preparing food ink that can be universally applied to all food materials that can be powdered. In addition, the present invention can be applied to a 3D printing technique in which a powder and a hydrocolloid matrix are independently stored and mixed immediately before printing. This technique can minimize the inherent rheological differences between formulations with different food sources and compositions.
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- 2018
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278. Decomposition of Pine and Oak Litters as Affected by Their Lignin and Mineral Concentrations
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Woo-Jung Choi, Yong-Se Park†, Hyun-Jin Park†, and Sang-Mo Lee
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chemistry.chemical_compound ,chemistry ,Environmental chemistry ,Mineral (nutrient) ,Lignin ,Environmental science ,chemistry.chemical_element ,Decomposition ,Litter decomposition ,Nitrogen - Published
- 2018
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279. Effect of halloysite nanoclay on the physical, mechanical, and antioxidant properties of chitosan films incorporated with clove essential oil
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Seong Yeon Kim, Min Hyeock Lee, and Hyun Jin Park
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Aqueous solution ,Scanning electron microscope ,General Chemical Engineering ,04 agricultural and veterinary sciences ,02 engineering and technology ,General Chemistry ,Food chemistry ,engineering.material ,021001 nanoscience & nanotechnology ,040401 food science ,Halloysite ,law.invention ,Physical property ,Chitosan ,Colloid ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,Chemical engineering ,law ,engineering ,0210 nano-technology ,Essential oil ,Food Science - Abstract
In this study, chitosan (Ch)-based films containing clove essential oil (CEO) as an active agent were developed by incorporating halloysite nanotubes (HNTs) to stabilize the oil droplets. The physical, mechanical, and antioxidant properties of the films were investigated toward their application as food packaging materials. The water vapor barrier property of the films improved upon the addition of the CEO as well as HNTs, owing to the hydrophobicity of the CEO and formation of tortuous pathways by the HNTs. Scanning electron micrographs of films without HNTs showed a large number of micropores on the film surface while few pores were observed on the film surface with the HNTs. Further, the incorporation of CEO decreased the elongation of the film, whereas the HNT particles dispersed in the film matrix mitigated this effect. The antioxidant activity of the films with different concentrations of HNT was determined by total phenolic content, 2,2-diphenyl-1-picrylhydrazyl, and reducing power assays. The highest antioxidant activity was achieved for the Ch/CEO film with 15 wt% HNT. In migration studies, the release of CEO from the film was found to be faster in 50% ethanol (simulant for oil-in-water emulsions and alcoholic foods) than in 10% and 95% ethanol, which are stimulants of aqueous and fatty foods, respectively.
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- 2018
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280. A Comparison of the Effects of Teaching Paraphrasing Skills versus Summarizing Skills in Academic Korean
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Hyun-jin Park
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Academic writing ,Mathematics education ,Psychology - Published
- 2018
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281. Probiotic Properties ofLactobacillus PlantarumLRCC5193, a Plant-Origin Lactic Acid Bacterium Isolated from Kimchi and Its Use in Chocolates
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Pei Lei Tan, Hyun Jin Park, Seok Min Yoon, Sae Hun Kim, Jung Hoon Lim, and Siyoung Yang
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0301 basic medicine ,biology ,Bile acid ,Chemistry ,medicine.drug_class ,030106 microbiology ,biology.organism_classification ,law.invention ,Lactic acid ,03 medical and health sciences ,Probiotic ,chemistry.chemical_compound ,030104 developmental biology ,Pepsin ,law ,Lactobacillus ,biology.protein ,medicine ,Food microbiology ,Food science ,Incubation ,Lactobacillus plantarum ,Food Science - Abstract
This study involves an investigation of the probiotic properties of lactic acid bacteria isolated from Kimchi, and their potential applications in chocolate. Lactobacillus plantarum-LRCC5193 (LP-LRCC5193) demonstrated a significantly higher degree of heat, acid, and bile acid tolerance compared to other Kimchi isolates. The intestinal adhesion assay also revealed that 84.2 log percentage of LP-LRCC5193 adhered to the Caco-2 cells after 2 h of incubation. Furthermore, the lyophilized LP-LRCC5193 maintained 92.9 log percentage and 97.2 log percentage survival rate within artificial stomach juice (pH 2.5, pepsin 0.04%) and artificial intestinal juice (oxgall 0.5%, trypsin 0.04%, and pancreatin 0.04%), respectively. Meanwhile, we also found that lyophilized LP-LRCC5193 incorporated in chocolate exhibited significantly higher survivability than lyophilized LP-LRCC5193 in both artificial gastric and intestinal juice under 1 to 3 hr incubation, where the survivability was within the range of 96.3 to 98.5 log percentage, and 98.8 to 98.9 log percentage, respectively. A 6-month storage test further revealed that LP-LRCC5193 demonstrated higher stability than the lyophilized LP-LRCC5103 in 3 different temperature ranges, where the final survival rates were 97.2 log percentage (20 °C), 89.2 log percentage (33 °C), and 94.4 log percentage (15 to 30 °C/wk). Altogether, our data suggest that chocolate can be used as a tasty delivery vehicle for delivering putative probiotic strain, LP-LRCC5193 to the gastrointestinal tract. PRACTICAL APPLICATION: Lactobacillus plantarum LRCC5193 (LP-LRCC5193) isolated from Kimchi demonstrated high stability under gastrointestinal environmental stresses and good adhesion to the intestinal epithelial cells in vitro. In addition, LP-LRCC5193 containing chocolates remained highly stable after storage at room temperature for 6 months. Chocolate containing LP-LRCC5193 can thus be considered a promising probiotic delivery system.; © 2018 Institute of Food Technologists®.
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- 2018
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282. Correlation of anxiety factors and writing anxiety between Korean and the mother language: with a focus on Korean intermediate level language learners
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Hyun-jin Park
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Correlation ,First language ,medicine ,Anxiety ,medicine.symptom ,Psychology ,Intermediate level ,Developmental psychology ,Focus (linguistics) - Published
- 2018
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283. Pollutant Runoff Reduction Efficiency of Surface Cover, Vegetative Filter Strip and Vegetated Ridge for Korean Upland Fields: A Review
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Kwang-Sik Yoon, Han-Yong Kim, Se-In Park, Hye In Yang, Hyun-Jin Park, and Woo-Jung Choi
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Pollutant ,Hydrology ,Filter strip ,0208 environmental biotechnology ,Surface cover ,04 agricultural and veterinary sciences ,02 engineering and technology ,General Medicine ,020801 environmental engineering ,Reduction (complexity) ,040103 agronomy & agriculture ,Ridge (meteorology) ,0401 agriculture, forestry, and fisheries ,Environmental science ,Surface runoff - Published
- 2018
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284. Vortex tracking on visualized temperature fields in a rotating Rayleigh–Bénard convection
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Yuji Tasaka, Yuichi Murai, Hyun Jin Park, Daisuke Noto, and Takatoshi Yanagisawa
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Physics ,Convection ,Advection ,Template matching ,Rayleigh number ,Mechanics ,Condensed Matter Physics ,Tracking (particle physics) ,01 natural sciences ,010305 fluids & plasmas ,Vortex ,Physics::Fluid Dynamics ,010309 optics ,Liquid crystal ,Condensed Matter::Superconductivity ,0103 physical sciences ,Electrical and Electronic Engineering ,Rayleigh–Bénard convection - Abstract
We established a vortex detection method using instantaneous temperature fields that were visualized using thermochromic liquid crystals (TLCs) to investigate behaviors of vortical structures in a rotating Rayleigh–Benard convection. Experimental testing was performed at a fixed Rayleigh number $$Ra = 1.0 \times 10^7$$ and different Taylor numbers from $$Ta = 1.0 \times 10^6$$ to $$1.0 \times 10^8$$ in water containing encapsulated TLCs. Vortices were recognized as undulations that appear in the horizontal temperature fields, thus making vortex detection with high spatial resolution possible, and this enabled quantitative investigation of the dynamics of vortical structures. Standard template matching was used to detect individual vortices on visualized temperature fields, and two-dimensional curved surface fitting was adopted to remove erroneous detections and to evaluate shapes of local temperature fields corresponding to vortical structures. Additionally, vortex tracking clearly showed geometric advection pattern of vortical structures.
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- 2018
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285. Rheological properties of montmorillonite dispersions in dilute NaCl concentration investigated by ultrasonic spinning rheometry
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Shingo Tanaka, Yuji Tasaka, Hyun Jin Park, Yuichi Murai, and Taiki Yoshida
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Materials science ,01 natural sciences ,Viscoelasticity ,010305 fluids & plasmas ,Physics::Fluid Dynamics ,chemistry.chemical_compound ,Rheology ,Geochemistry and Petrology ,0103 physical sciences ,Ultrasound ,Composite material ,Spinning ,Montmorillonite ,010304 chemical physics ,Rheometry ,Geology ,Shear-thinning viscosity ,Condensed Matter::Soft Condensed Matter ,Shear rate ,Shear (geology) ,chemistry ,Dispersion (chemistry) ,Shear banding - Abstract
Rheological changes of gelled montmorillonite dispersions with different NaCl concentrations and alkali conditions were evaluated by ultrasonic spinning rheometry. It uses velocity-profile information that is obtained in an open-cylindrical container under periodic oscillations. The measurement was conducted with a focus on the rheological behavior at a low shear rate O(1 s−1), which is difficult to measure because of shear banding. The rheometry represents the coexistence of gel and sol conditions in dispersions as profiles of the phase lag of oscillations that are propagated from the cylinder wall. The critical shear rate at a yielding point and the onset of shear-thinning behavior was quantified, which has been regarded as only an apparent or speculated value by many previous researchers. Viscoelasticity from particle networks in the dispersion was observed, and the networks deform like a spring, without breaking the structure under low-shear-rate conditions.
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- 2018
286. Comparative study of the effects of cigarette smoke and electronic cigarettes on human gingival fibroblast proliferation, migration and apoptosis
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Mahmoud Rouabhia, Hyun Jin Park, Abdelhabib Semlali, Jamila Chakir, and Humidah Alanazi
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0301 basic medicine ,Nicotine ,Cell ,Gingiva ,Apoptosis ,Electronic Nicotine Delivery Systems ,Toxicology ,Fibroblast migration ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,Smoke ,Proliferation rate ,Tobacco ,Cell Adhesion ,In Situ Nick-End Labeling ,medicine ,Humans ,Cigarette smoke ,Cell Proliferation ,Wound Healing ,Chemistry ,030206 dentistry ,General Medicine ,Fibroblasts ,030104 developmental biology ,medicine.anatomical_structure ,Cancer research ,Gingival fibroblast ,Wound healing ,Food Science ,medicine.drug - Abstract
In an effort to reduce smoking-related diseases, alternative products such as e-cigarettes have been proposed. However, despite their growing popularity, the potential toxicity of e-cigarettes remains largely unknown. In this study, human gingival fibroblasts were repeatedly exposed to cigarette smoke condensate (CSC) and to nicotine-rich (NR) or nicotine-free (NF) e-vapor condensates for 60 min once a day for various time periods. They were then used to perform different analyses. Results indicate that cells exposed to CSC or NR condensates showed an altered morphology and a reduced proliferation rate, as ascertained by MTT and BrdU assays. Fibroblast cultures exposed to either CSC or e-vapor condensates also showed increased levels of TUNEL-positive apoptotic cells, compared to that recorded in the control. Furthermore, the cell scratch test revealed that repeated exposures to CSC or to e-vapor condensates delayed both fibroblast migration and wound healing. It should be noted that CSC was much more damageable to gingival fibroblasts than were the NR and NF e-vapor condensates. The representative chain of damage thus translates to CSC > NR e-vapor condensate > NF e-vapor condensate.
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- 2018
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287. Design and Analysis of Multicast Based Lightweight Demand Response Protocol for Energy IoT Environment
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Choi Jin Seek, Hyun Jin Park, Sung-Hwan Lee, and Park Heonil
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Demand response ,MQTT ,Multicast ,business.industry ,Computer science ,business ,Internet of Things ,Protocol (object-oriented programming) ,Energy (signal processing) ,Computer network - Published
- 2018
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288. Speciation of Bio-Available Iodine in Abalone (Haliotis discus hannai ) by High-Performance Liquid Chromatography Hyphenated with Inductively Coupled Plasma-Mass Spectrometry Using an In Vitro Method
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Hyun Jin Park and Hansol Doh
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chemistry.chemical_classification ,Chromatography ,biology ,Abalone ,010401 analytical chemistry ,Iodide ,chemistry.chemical_element ,04 agricultural and veterinary sciences ,Iodine ,biology.organism_classification ,040401 food science ,01 natural sciences ,High-performance liquid chromatography ,0104 chemical sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,Haliotis discus ,Digestion ,Inductively coupled plasma mass spectrometry ,Iodate ,Food Science - Abstract
Abalone is one of the most valuable marine products found in East Asia because it is rich in nutritious substances including iodine. In this study, the in vitrodialyzability approach was used to assess the bio-available iodine species in abalone. Iodide, iodate, 3-iodo-L-tyrosine (MIT), and 3,5-diiodo-L-tyrosine (DIT) were separated by high-performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). To assure the consistency, reliability, and accuracy of the data, the method was validated. Comparison of the total iodine in abalone muscle and viscera indicated that abalone muscle showed greater digestion/absorption efficiency than abalone viscera (digestion efficiency: 68.13 ± 2.59% and 47.88 ± 5.76% and absorption efficiency: 59.78 ± 2.93% and 35.12 ± 1.43% for abalone viscera and muscle, respectively). However, evaluation of the sum of the analyzed iodine species targeted in this study by HPLC-ICP-MS indicated that abalone muscle showed lower digestion efficiency and similar absorption efficiency compared to that of abalone viscera (digestion efficiency: 35.52 ± 5.41% and 28.84 ± 1.83%; absorption efficiency: 23.56 ± 4.38% and 27.56 ± 1.51% for abalone viscera and muscle, respectively). The main forms of iodine detected in abalone muscle were iodide and MIT, whereas iodide was the major form in abalone viscera. The bio-available iodine in abalone was quantified via an in vitromethod employing HPLC-ICP-MS. The results of this study indicated that abalone is feasible as a new iodine source and may prospectively find application in iodine-fortified foods.
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- 2018
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289. Preparation of Novel Iodized Salt with Natural Iodine-Rich Sources by Spray Drying
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Hyun Jin Park, Hansol Doh, and Jung A Ko
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food.ingredient ,Food industry ,biology ,business.industry ,Sea salt ,Extraction (chemistry) ,chemistry.chemical_element ,04 agricultural and veterinary sciences ,Iodine ,biology.organism_classification ,040401 food science ,Hot water extraction ,Iodised salt ,0404 agricultural biotechnology ,food ,chemistry ,Spray drying ,Haliotis discus ,Food science ,business ,Food Science - Abstract
Marine products are rich in not only micronutrients but also iodine content. However, the applications of iodine in marine products in the food industry have not been studied extensively. Therefore, in this study, a novel iodized salt was prepared through a simple method for iodine extraction from natural iodine‐rich sources and spray drying. Laminaria ochroleuca(kombu), Porphyra umbilicalis(nori), Undaria pinnatifida(wakame), and Haliotis discus hannai(abalone) were selected as natural iodine‐rich sources. Through hot water extraction, iodine was extracted from the iodine‐rich sources and iodized salt was successfully prepared with extracted iodine and sea salt by spray drying; extraction efficiency varied from 64.88% to 129.67%; yield, 38.45% to 57.09%; loading efficiency, 99.34% to 124.08%. Chemical interactions were assessed using Fourier transform infrared spectroscopy (FT‐IR) and thermal dynamics was evaluated using differential scanning calorimetry (DSC). Morphology of the salt crystals was studied using scanning electron microscopy (SEM). Furthermore, a storage test was performed to investigate iodine loss due to temperature, relative humidity, and oxidation for 10 weeks in harsh condition. On comparing our salt with commercial products, novel iodized salts displayed similar or superior stability. Therefore, the novel iodized salt prepared in this study can be applied in the food industry. Iodine is essential trace element and plays a key role in our body. Marine products such as Laminaria ochroleuca(Kombu), Porphyra umbilicalis(nori), Undaria pinnatifida(wakame), and Haliotis discus hannai(abalone) are known as iodine rich‐sources. These products have high level of iodine, but iodine in marine products has not been used widely for food industry. Therefore, using iodine in natural sources, novel iodized salt was prepared with simple method (hot water extraction and spray drying). The novel iodized salt prepared in this study can be applied in the food industry.
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- 2018
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290. δ13C, δ15N, N concentration, C/N, and Ca/Al of Pinus densiflora foliage in Korean cities of different precipitation pH and atmospheric NO2 and SO2 levels
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Scott X. Chang, Hyun-Jin Park, Kwang-Seung Lee, Sang-Mo Lee, Hye In Yang, Jin-Hyeob Kwak, Woo-Jung Choi, Sang-Sun Lim, and Seung-Il Lee
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Pollutant ,Pollution ,010504 meteorology & atmospheric sciences ,Ecology ,δ13C ,biology ,media_common.quotation_subject ,food and beverages ,General Decision Sciences ,chemistry.chemical_element ,δ15N ,010501 environmental sciences ,biology.organism_classification ,01 natural sciences ,Nitrogen ,Pinus densiflora ,chemistry ,Environmental chemistry ,Precipitation ,Carbon ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,media_common - Abstract
Forest decline due to atmospheric pollution is a consequence of long-term chronic exposure, and thus chemical proxies that are sensitive to the pollution are helpful in estimating the impact of atmospheric pollution on forest health. In this study, we explored changes in the isotopic and elemental compositions of needles of red pine (Pinus densiflora) with varying precipitation pH and concentrations of NO2 and SO2 across 18 cities to identify isotopic and chemical signatures that are sensitive to acid deposition. The cities had different intensity of traffic and industrial activities, and thus were expected to have varying levels of atmospheric pollution. The pine needles were analyzed for carbon (δ13C) and nitrogen (δ15N) isotope ratios, N concentrations, C-to-N ratio (C/N), and calcium-to-aluminum ratio (Ca/Al). Analysis of variance, simple linear correlation, and redundancy analysis were used to investigate the variations in foliar chemistry with atmospheric variables. Neither NO2 nor SO2 concentration was correlated with foliar δ13C, δ15N, N concentration, and C/N; whereas precipitation pH was correlated with the foliar parameters, suggesting that foliar chemistry is more sensitive to total acidifying materials than to individual pollutant. The foliar δ13C decreased with lowered precipitation pH, reflecting the increased 13C-depleted CO2 that was co-emitted with acidifying materials from fossil fuel combustion. Foliar δ15N decreased and foliar N concentration increased with lowered precipitation pH, indicating tree uptake of 15N-depleted N from acid deposition. Accordingly, the C/N ratio also decreased with lowered precipitation pH. However, there was no relationship between foliar Ca/Al and precipitation pH; rather. Our result suggests that δ13C, δ15N, N concentration, and C/N of pine needle samples are associated with the level of precipitation pH and thus pine needles could be used as bio-indicators of the impacts of total acidifying pollutants on forest.
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- 2018
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291. Soil organic carbon stocks in three Canadian agroforestry systems: From surface organic to deeper mineral soils
- Author
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Samiran Banerjee, Cameron N. Carlyle, Sang-Sun Lim, Edward W. Bork, Farrah R. Fatemi, Mark Baah-Acheamfour, Muhammad Arshad, Scott X. Chang, Hyun-Jin Park, and Woo-Jung Choi
- Subjects
010504 meteorology & atmospheric sciences ,Agroforestry ,Forestry ,04 agricultural and veterinary sciences ,Soil carbon ,Management, Monitoring, Policy and Law ,Windbreak ,01 natural sciences ,Humus ,Soil water ,040103 agronomy & agriculture ,Soil organic carbon stocks ,0401 agriculture, forestry, and fisheries ,Environmental science ,Soil horizon ,Silvopasture ,0105 earth and related environmental sciences ,Nature and Landscape Conservation - Abstract
Our understanding of the effect of agroforestry systems on soil organic carbon (SOC) is largely limited to the upper layer of the mineral soil, while LFH (litter, partially decomposed litter and humus) and deeper soil layers are poorly studied. In this study, the effects of three different agroforestry systems (hedgerow, shelterbelt, and silvopasture) and their component land-cover types (treed area and adjacent herbland) on SOC stock in LFH and mineral soil layers (0–75 cm) were investigated across 36 sites in central Alberta, Canada. The SOC stock of mineral soil (0–75 cm) was not affected by agroforestry systems but by land-cover type. The treed area had greater (p
- Published
- 2018
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292. Sorption of Pb in chemical and particle-size fractions of soils with different physico-chemical properties
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Jin-Hyeob Kwak, Hye In Yang, Goon-Taek Lee, Sang-Mo Lee, Se-In Park, Man Park, Hyun-Jin Park, Woo-Jung Choi, Hyun-Jung Park, and Sang-Sun Lim
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chemistry.chemical_classification ,Stratigraphy ,Sorption ,04 agricultural and veterinary sciences ,Fractionation ,010501 environmental sciences ,Silt ,01 natural sciences ,chemistry ,Environmental chemistry ,Soil water ,040103 agronomy & agriculture ,Cation-exchange capacity ,0401 agriculture, forestry, and fisheries ,Organic matter ,Clay minerals ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Volcanic ash - Abstract
Lead (Pb) sorption capacity (PbSmax) and distribution in chemical and particle-size fractions of six soils with different physico-chemical properties were investigated to explore the principal properties of soils that affect Pb sorption. A series of experiments of Pb sorption and soil chemical and particle-size fractionation of sorbed Pb were conducted with six soils of different texture, mineralogy, organic matter concentration, cation exchange capacity (CEC), and Fe-Mn concentrations. Soils either developed from volcanic ash or containing smectite showed relatively higher PbSmax than the other soils. Across the soils, clay content, organic matter concentration, and total Fe concentrations were significantly (p
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- 2018
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293. Groundwater recharge analysis and comparison using hybrid water-table fluctuation method and groundwater modeling: a case of Gangcheon basin in Yeoju City
- Author
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Jae-Yeol Cheong, Se-Yeong Hamm, Dal Nim Noh, and Hyun Jin Park
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Hydrology ,010504 meteorology & atmospheric sciences ,Water table ,0208 environmental biotechnology ,Geology ,02 engineering and technology ,Groundwater recharge ,Structural basin ,01 natural sciences ,020801 environmental engineering ,Earth and Planetary Sciences (miscellaneous) ,Environmental science ,Groundwater model ,0105 earth and related environmental sciences - Published
- 2018
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294. Elevated CO2 concentration affected pine and oak litter chemistry and the respiration and microbial biomass of soils amended with these litters
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Hyun-Jin Park, Hye-In Yang, Kwang-Seung Lee, Woo-Jung Choi, Young Han Lee, Jin-Hyeob Kwak, Sang-Sun Lim, and Han-Yong Kim
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0106 biological sciences ,Litter (animal) ,Soil Science ,Biomass ,complex mixtures ,010603 evolutionary biology ,01 natural sciences ,Microbiology ,Soil respiration ,chemistry.chemical_compound ,Pinus densiflora ,Lignin ,reproductive and urinary physiology ,biology ,fungi ,technology, industry, and agriculture ,food and beverages ,Soil chemistry ,04 agricultural and veterinary sciences ,Plant litter ,biology.organism_classification ,chemistry ,Environmental chemistry ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Quercus variabilis ,Agronomy and Crop Science - Abstract
Elevated atmospheric CO2 concentration ([CO2]) may change litter chemistry which affects litter decomposability. This study investigated respiration and microbial biomass of soils amended with litter of Pinus densiflora (a coniferous species; pine) and Quercus variabilis (a deciduous species; oak) that were grown under different atmospheric [CO2] and thus had different chemistry. Elevated [CO2] increased lignin/N through increased lignin concentration and decreased N concentration. The CO2 emission from the soils amended with litter produced under the same [CO2] regime was greater for oak than pine litter, confirming that broadleaf litter with lower lignin decomposes faster than needle leaf litter. Within each species, however, soils amended with high lignin/N litter grown under elevated [CO2] emitted more CO2 than those with low lignin/N litter grown under ambient [CO2]. Such contrasting effects of lignin/N on inter- and intra-species variations in litter decomposition should be ascribed to the effects of other litter chemistry variables including nonstructural carbohydrate, calcium and manganese as well as inhibitory effect of N on lignin decomposition. The microbial biomass was also higher in the soils amended with high lignin/N litter than those with low lignin/N litter probably due to low substrate use efficiency of lignin by microbes. Our study suggests that elevated [CO2] increases lignin/N for both species, but increased lignin/N does not always reduce soil respiration and microbial biomass. Further study investigating a variety of tree species is required for more comprehensive understanding of inter- and intra-species variations of litter decomposition under elevated [CO2].
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- 2018
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295. Surface treatment with amino acids of porous collagen based scaffolds to improve cell adhesion and proliferation
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Nabila Mighri, Hyun Jin Park, Frej Mighri, Jifu Mao, Ze Zhang, Mahmoud Rouabhia, and Abdallah Ajji
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chemistry.chemical_classification ,General Chemical Engineering ,0206 medical engineering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Amino acid ,Chitosan ,chemistry.chemical_compound ,chemistry ,Biophysics ,0210 nano-technology ,Cell adhesion ,Porosity ,Collagen scaffold - Published
- 2018
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296. Design and Analysis of Push Mechanism Based on CoAP Observe for Demand Response in Energy IoT Environment
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Sung-Hwan Lee, Hyun Jin Park, Choi Jin Seek, and Park Heonil
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Demand response ,business.industry ,Computer science ,Distributed computing ,Mechanism based ,Internet of Things ,business ,Energy (signal processing) - Published
- 2018
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297. Reprint of: Classification of the printability of selected food for 3D printing: Development of an assessment method using hydrocolloids as reference material
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Hyunwoo Kim, Hojae Bae, and Hyun Jin Park
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0301 basic medicine ,Engineering drawing ,030109 nutrition & dietetics ,Materials science ,Stability test ,business.industry ,3D printing ,04 agricultural and veterinary sciences ,040401 food science ,Shear modulus ,03 medical and health sciences ,0404 agricultural biotechnology ,Shear rheology ,Assessment methods ,Extrusion ,Process engineering ,business ,Food Science - Abstract
The printability of materials used in extrusion based 3D printing is one of the most important properties especially when fabricating objects with architectural complexities. However, this parameter is influenced by several factors (temperature, components, and additives) which makes thorough evaluation and classification challenging. In this study, the printability of food-ink for 3D food printing applications was evaluated by systematically adapting evaluation techniques such as dimensional stability test, handling properties assessment, and shear rheology test using edible hydrocolloid as reference materials. Methylcellulose (MC) was selected as a suitable reference material for its capability to simulate the printability of various types of food applications. In dimensional stability test, the concentrations of reference hydrocolloid mixture that could fabricate structures with height of 20, 40, and 80 mm without significant collapse were 9%, 11%, and 13%, respectively. The deformation behavior and handling properties of printed foods were classified based on the reference material produced at various concentrations (5%–20%). Shear modulus of all samples were in complete agreement with simulation results based on the dimensional stability test indicating that the printability of foods can be predicted and classified by comparing its properties to reference material. The newly established classification system of printability was categorized into grades A, B, C, and D according to the dimensional stability and degree of handling. The validity of this classification system was verified by 3D-printing tests.
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- 2018
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298. Successful treatment of refractory CMV colitis after haploidentical HSCT with post-transplant cyclophosphamide using CD45RA+ depleted donor lymphocyte infusion
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Kyung Taek Hong, Hong Yul Ahn, Sun Ok Yun, Hee Young Shin, Hyun Jin Park, Jung Yoon Choi, and Hyoung Jin Kang
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Transplantation ,medicine.medical_specialty ,Refractory ,business.industry ,Post transplant cyclophosphamide ,Internal medicine ,medicine ,Hematology ,Colitis ,business ,medicine.disease ,Gastroenterology ,Donor lymphocyte infusion - Published
- 2019
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299. Surgical site contamination and infection following transforaminal lumbar interbody fusion using biportal endoscopic versus open microscopic technique: A prospective cohort study
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Hyun-Jin Park
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- 2022
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300. Spatial development of single void pulse in a horizontal turbulent bubbly channel flow investigated by a time-resolved two-laser measurement
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Yuji Tasaka, Hyun Jin Park, and Yuichi Murai
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Fluid Flow and Transfer Processes ,Physics ,Advection ,Turbulence ,Mechanical Engineering ,General Physics and Astronomy ,Mechanics ,Pulse (physics) ,Open-channel flow ,Local Void ,Physics::Fluid Dynamics ,Drag ,Void (composites) ,Korteweg–de Vries equation - Abstract
The presence of void waves, alternative dense and sparse distribution of bubbles, can promote frictional drag reduction in horizontal turbulent boundary layers compared with the uniform passage of bubbles. This paper aims to determine how long a void pulse (i.e. simplest waveform in void waves) can persist downstream. First, we explored the internal structure of the void pulse and its spatial development by establishing a time-resolved two-laser measurement system. Then, advection and distortion of the pulse were analyzed and modeled by a one-dimensional Korteweg de Vries–Burgers (KdV–B) equation for water including and excluding surfactant, leading to the following conclusions; (i) the KdV–B equation well approximates the measured void pulse behavior and can be used as a mathematical predictor for the downstream propagation, (ii) advection velocity and diffusion of the pulses are explained by the velocity variation of bubbles and the depth of the bubbly layer, (iii) the pulse contains significant nonlinear advection velocity associated to local void fraction, and it causes the pulse to lean backward to retain a sharp streamwise gradient in each rear part of the pulse, and (iv) the pulse finally disappears in the channel flow because it does not include the solitary wave appearing in the KdV equation, judged by a combination of the nonlinear advection velocity and the dispersion coefficient.
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- 2022
- Full Text
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