• Journal of the Korean Society of Visualization
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• v.6 no.1
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• pp.41-46
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• 2008

In this paper, the recirculation flow motion and mixing characteristics driven by air bubble stream in a rectangular water tank is studied. The time-resolved PIV technique is adopted for the quantitative visualization and analysis. 488 nm Ar-ion CW laser is used for illumination and orange fluorescent ($\lambda_{ex}=540nm,\;\lambda_{em}=560nm$) particle images are acquired by a PCO 10bit high-speed CCD camera (1280$\times$1024). To obtain clean particle images, 545 nm long pass optical filter and an image intensifier are employed and the flow rates of compressed air is 3 l/min at 0.5 MPa. The recirculation and mixing flow field is further investigated by time-resolved POD analysis technique. It is observed that the large scale recirculation resulting from the interaction between rising bubble stream and side wall is the most dominant flow structure and there are small scale vortex structures moving along with large scale recirculation flow. It is also verified that the sum of 20 modes of velocity field has about 67.4% of total turbulent energy.

• Journal of Forest and Environmental Science
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• v.38 no.1
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• pp.12-20
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• 2022

Pongamia (Pongamia pinnata L.) as a source of non-edible oil, is potential tree species for biodiesel production. For several reasons, both technical and economical, the potential of P. pinnata is far from being realized. The exploitation of genetic diversity for crop improvement has been the major driving force for the exploration and ex situ/in situ conservation of plant genetic resources. However, P. pinnata improvement for high oil and seed production is not achieved because of unsystematic way of tree improvement. Performance of P. pinnata planted by Karnataka Forest Department was assessed based on yield potential by collecting 157 clones out of 264 clones established by Karnataka Forest Department research wing under different research circles/ranges. It was evident that the all the seed and pod traits were significantly different. Further, selection of superior germplasm based on oil and pod/seed parameters was achieved by application of Mahalanobis statistics and Tocher's technique. On the basis of D² values for all possible 253 pairs of populations the 157 genotypes were grouped into 28 clusters. The clustering pattern showed that geographical diversity is not necessarily related to genetic diversity. Cluster means indicated a wide range of variation for all the pod and seed traits. The best cluster having total oil content of more than 34.9% with 100 seed weight of above 125 g viz. Cluster I, II, III, IX, XV, XIX, XXI, XXIII, XXVI and XXVII were selected for clonal propagation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.707-712
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• 2014

Purpose: Anastomotic leakage (AL) is associated with high morbidity and mortality, high reoperation rates, and increased hospital length of stay. Here we investigated the risk factors for AL after anterior resection for rectal cancer with a double stapling technique. Patients and Methods: Data for 460 patients who underwent primary anterior resection with a double stapling technique for rectal carcinoma at a single institution from 2003 to 2007 were prospectively collected. All patients experienced a total mesorectal excision (TME) operation. Clinical AL was defined as the presence of leakage signs and confirmed by diagnostic work-up according to ICD-9 codes 997.4, 567.22 (abdominopelvic abscess), and 569.81 (fistula of the intestine). Univariate and logistic regression analyses of 20 variables were undertaken to determine risk factors for AL. Survival was analysed using the Cox regression method. Results: AL was noted in 35 (7.6%) of 460 patients with rectal cancer. :Median age of the patients was 65 (50-74) and 161 (35%) were male. The diagnosis of AL was made between the 6th and 12th postoperative day (POD; mean 8th POD). After univariate and multivariate analysis, age (p=0.004), gender (p=0.007), tumor site (p<0.001), preoperative body mass index (EMI) (p<0.001), the reduction of TSGF on 5th POD less than 10U/ml (p=0.044) and the pH value of pelvic dranage less than or equal to 6.978 on 3rd POD (p<0.001) were selected as 6 independent risk factors for AL. It was shown that significant differences in survival of the patients were AL-related (p<0.001), high ASA score related (p=0.036), high-level EMI related (p=0.007) and advanced TNM stage related

• Journal of Korean Neurosurgical Society
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• v.62 no.5
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• pp.561-566
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• 2019

Objective : Functional outcomes have traditionally been evaluated and compared using subjective surveys, such as visual analog scores (VAS), the Oswestry disability index (ODI), and Short Form-36 (SF-36), to assess symptoms and quality of life. However, these surveys are limited by their subjective natures and inherent bias caused by differences in patient perceptions of symptoms. The Fitbit $Charge^{(R)}$ (Fitbit Inc., San Francisco, CA, USA) provides accurate and objective measures of physical activity. The use of this device in patients after laminectomy would provide objective physical measures that define ambulatory function, activity level, and degree of recovery. Therefore, the present study was conducted to identify relationships between the number of steps taken by patients per day and VAS pain scores, prognoses, and postoperative functional outcomes. Methods : We prospectively investigated 22 consecutive patients that underwent laminectomy for spinal stenosis or a herniated lumbar disc between June 2015 and April 2016 by the same surgeon. When patients were admitted for surgery and first visited after surgery, preoperative and postoperative functional scores were recorded using VAS scores, ODI scores, and SF-36. The VAS scores and physical activities were recorded daily from postoperative day (POD) 1 to POD 7. The relationship between daily VAS scores and daily physical activities were investigated by simple correlation analysis and the relationship between mean number of steps taken and ODI scores after surgery was subjected to simple regression analysis. In addition, Wilcoxon's signed-rank test was used to investigate the significance of pre-to-postoperative differences in VAS, ODI, and SF-36 scores. Results : Pre-to-postoperative VAS (p<0.001), ODI (p<0.001), SF-36 mental composite scores (p=0.009), and SF-36 physical composite scores (p<0.001) scores were found to be significantly different. Numbers of steps taken from POD 1 to POD 7 were negatively correlated with daily VAS scores (r=-0.981, p<0.001). In addition, the mean number of steps from POD 3 to POD 7 and the decrease in ODI conducted one month after surgery were statistically significant (p=0.029). Conclusion : Wearable devices are not only being used increasingly by consumers as lifestyle devices, but are also progressively being used in the medical area. This is the first study to demonstrate the usefulness of a wearable device for checking patient physical activity and predicting pain and prognosis after laminectomy. Based on our experience, the wearable device used to provide measures of physical activity in the present study has the potential to provide objective information on pain severity and prognosis.

• BMB Reports
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• v.41 no.3
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• pp.259-265
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• 2008

Three peroxidase (POD) cDNAs were isolated from dehydration-treated fibrous roots of sweetpotato (Ipomoea batatas) plant via the screening of a cDNA library, and their expressions were assessed to characterize functions of each POD in relation to environmental stress. Three PODs were divided into two groups, designated the basic PODs (swpb4, swpb5) and the anionic PODs (swpa7), on the basis of the pI values of mature proteins. Fluorescence microscope analysis indicated that three PODs are secreted into the extracellular space. RT-PCR analysis revealed that POD genes have diverse expression patterns in a variety of plant tissues. Swpb4 was abundantly expressed in stem tissues, whereas the expression levels of swpb5 and swpa7 transcripts were high in fibrous and thick pigmented roots. Swpb4 and swpa7 showed abundant expression levels in suspension cultured cells. Three POD genes responded differently in the leaf and fibrous roots in response to a variety of stresses including dehydration, temperature stress, stress-associated chemicals, and pathogenic bacteria.

• Journal of computational fluids engineering
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• v.22 no.1
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• pp.59-66
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• 2017

The guideline of selecting the number of snapshot dataset, $N_s$ in proper orthogonal decomposition(POD) was presented via the analysis of Eigen values based on the singular value decomposition(SVD). In POD, snapshot datasets from the solutions of Euler or Navier-Stokes equations are utilized to SVD and a reduced order model(ROM) is constructed as the combination of Eigen vectors. The ROM is subsequently applied to reconstruct the flowfield data with new set of flow conditions, thereby enhancing the computational efficiency. The overall computational efficiency and accuracy of POD is dependent on the number of snapshot dataset; however, there is no reliable guideline of determining $N_s$. In order to resolve this problem, the order of maximum to minimum Eigen value ratio, O(R) from SVD was analyzed and presented for the decision of $N_s$; in case of steady flow, $N_s$ should be determined to make O(R) be $10^9$. For unsteady flow, $N_s$ should be increased to make O(R) be $10^{11\sim12}$. This strategy of selecting the snapshot dataset was applied to two dimensional NACA0012 airfoil and vortex flow problems including steady and unsteady cases and the numerical accuracies according to $N_s$ and O(R) were discussed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.8
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• pp.677-683
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• 2015

Hybrid rocket combustion displays low frequency instability(LFI, 10~30Hz) at a certain condition. Vortex shedding in the post-chamber is suspected to cause the occurrence of LFI. This study focused on the visualization of flow image using light emissions from high temperature combustion gas. Results shows that combustion pressure oscillates at a frequency of about 18 Hz, which is in phase with oscillations of light emission. Since LFI is not a property of thermo-acoustic instability, this result suggested there exists a physical coupling of pressure fluctuations with light emissions proportional to chemical reaction. Also POD analysis shows that dominant symmetric spatial modes in the stable combustion shift suddenly into asymmetric spatial pattern with the appearance of LFI. Especially, the appearance of mode 3 is a typical change of flow dynamics in unstable combustion representing a rotational fluid motions associated with vortex shedding.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.393-399
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• 2023

Objective : Chiari II malformation (CM II) is still the main cause of severe morbidity and mortality in children with open neural tube defects (ONTDs). The goal of this study was to validate a CM II model in late-stage chick embryos with surgically induced ONTDs. Methods : To make the chick embryo model of ONTD, their neural tubes were opened for a length of 5-6 somites at the thoracic level in Hamburger and Hamilton stage 18 chick embryos (n=150). They were reincubated in ovo up to a total age of 17-21 days. A total of 19 embryos survived and were assigned to either the postoperative day (POD) 14-15 group (n=6) or the POD 17-18 group (n=13). Magnetic resonance imaging (MRI) and histopathologic findings of embryo heads with spinal ONTDs were compared with age-matched normal chick embryos. Results : The chick embryos with ONTDs demonstrated definite and constant structural changes, such as downward displacement of the cerebellum to just above the foramen magnum and narrow and small cerebrospinal fluid spaces in the crowded small posterior fossa. These morphologic features were more prominent in the POD 17-18 group than in the POD 14-15 group. Conclusion : This is the first description of CM II with spinal ONTD in a late-stage chick embryo model with MRI and histopathological analysis. The morphological changes of the posterior fossa in this study mimic those of CM II associated with spinal ONTD in humans. This model will facilitate investigation of the pathogenesis of CM II.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.599-605
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• 2007

Seed and pod numbers are the main yield components in soybean. Selection for increased yield potential is main goal of plant breeding. The objective of this study was to identify quantitative trait loci(QTLs) that control pod number per plant, seed number per plant and pod in soybean. The 117 $F_{2:10}$ recombinant inbred lines(RILs) developed from a cross of 'Keunolkong' and 'Shinpaldalkong' were used. Two independent QTLs for pod number per plant were identified from linkage group(LG) F and L. Two QTLs for seed number per plant were located on LG F and L. Seed number per pod was related with three QTLs located on LG D1a, D1b and F. Pod and seed number per plant have two common QTLs on LG F and L.

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

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