Seungwon Lee

RNA-Seq approach for genetic improvement of meat quality in pig and evolutionary insight into the substrate specificity of animal carbonyl reductases.

Changes in meat quality traits are strongly associated with alterations in postmortem metabolism which depend on genetic variations, especially nonsynonymous single nucleotide variations (nsSNVs) having critical effects on protein structure and function. To selectively identify metabolism-related nsSNVs, next-generation transcriptome sequencing (RNA-Seq) was carried out using RNAs from porcine liver, which contains a diverse range of metabolic enzymes. The multiplex SNV genotyping analysis showed that various metabolism-related genes had different nsSNV alleles. Moreover, many nsSNVs were significantly associated with multiple meat quality traits. Particularly, ch7:g.22112616A>G SNV was identified to create a single amino acid change (Thr/Ala) at the 145th residue of H1.3-like protein, very close to the putative 147th threonine phosphorylation site, suggesting that the nsSNV may affect multiple meat quality traits by affecting the epigenetic regulation of postmortem metabolism-related gene expression. Besides, one nonsynonymous variation, probably generated by gene duplication, led to a stop signal in porcine testicular carbonyl reductase (PTCR), resulting in a C-terminal (E281-A288) deletion. Molecular docking and energy minimization calculations indicated that the binding affinity of wild-type PTCR to 5α-DHT, a C21-steroid, was superior to that of C-terminal-deleted PTCR or human carbonyl reductase, which was very consistent with experimental data, reported previously. Furthermore, P284 was identified as an important residue mediating the specific interaction between PTCR and 5α-DHT, and phylogenetic analysis showed that P284 is an evolutionarily conserved residue among animal carbonyl reductases, which suggests that the C-terminal tails of these reductases may have evolved under evolutionary pressure to increase the substrate specificity for C21-steroids and facilitate metabolic adaptation. Altogether, our RNA-Seq revealed that selective nsSNVs were associated with meat quality traits that could be useful for successful marker-assisted selection in pigs and also represents a useful resource to enhance understanding of protein folding, substrate specificity, and the evolution of enzymes such as carbonyl reductase.

Structural and optical properties of Mn2+ and Li+ codoped ZnGa2O3.95M0.05 (M = S, Se, and Te) phosphors

Abstract Structural and optical properties on various kinds of Mn2+ and Li+ codoped ZnGa2O3.95M0.05 (M=S, Se, and Te) were investigated by using X-ray diffraction (XRD), cathodoluminescence (CL), and photoluminescence excitation (PLE) measurements. The results of the XRD patterns showed that the lattice constants of the ZnGa2O3.95M0.05:Mn2+, Li+ decrease with the substitution of S, Se, and Te for the oxygen in the ZnGa2O4. The CL and PLE spectra exhibited that the luminescence intensity of the ZnGa2O3.95Se0.05:Mn2+, Li+ was the strongest among various samples studied in this work. The enhancement of the luminescence intensity in the ZnGa2O3.95Se0.05:Mn2+, Li+ originated from the increase of the conductivity due to Li+ doping. These results can help improve understanding Mn2+ and Li+ doped ZnGa2O3.95Se0.05 phosphors for the application in field-emission display devices with high brightness.

Multi-View Video and Multi-Channel Audio Broadcasting System

In recent years, various multimedia services have become available and the demand for realistic multimedia systems is growing rapidly. The multi-view video and multi-channel audio are expected to satisfy the user demand for realistic multimedia services. In this paper, we present a new broadcasting system incorporating multi-view video and multi-channel audio over IPTV and MPEG-21 DIA. The proposed system includes data acquisition, camera calibration, data encoding and decoding, transmission, intermediate view reconstruction, and multi-view display and multi-channel audio play. In this paper, we discuss the main features of multi-view video and multi-channel audio.

Optical characteristics of emission from β-Ga2O3 with group-VIb ions

The first synthesis of single phased gallium oxysulfide (β-Ga 2 O 3-x S x ), gallium oxyselenide (β-Ga 2 O 3-x Se x ) and gallium oxytelluride (β-Ga 2 O 3-x Te x ) was actualized. The luminescence intensity of Ga 2 O 2.95 S 0.05 is the highest of the above samples, i.e., it shows fourfold enhancement in comparison with that of Ga 2 O 3 . Furthermore, the intensity of Ga 2 O 2.95 Se 0.05 and Ga 2 O 2.95 Te 0.05 is lower than that of Ga 2 O 3 . Those trends are attributed to the two effects of the electron delocalization and the distance between donor and acceptor. The spectra of VIb-ion-doped samples, i.e., Ga 2 O 2.95 S 0.05 , Ga 2 O 2.95 Se 0.05 and Ga 2 O 2.95 Te 0.05 , show a redshift behavior by 10 nm in comparison with that of Ga 2 O 3 . The redshift behavior can be explained by the Nephelauxetic effect. Our results showed a means of achieving emission intensity enhancement through changing the cation environment in β-Ga 2 O 3 .

Contingent association between the size of the social support network and osteoporosis among Korean elderly women

Objective To investigate the association between the number of personal ties (or the size of the social support network) and the incidence of osteoporosis among older women in Korea. Methods Data from the Korean Urban Rural Elderly Study were used. Bone density was measured by dual-energy X-ray absorptiometry at the lumbar spine (L1–L4) and femur neck. T-score, the standardized bone density compared with what is normally expected in a healthy young adult, was measured and the presence of osteoporosis was determined, if the T-score was < -2.5. The social support network size was measured by self-responses (number of confidants and spouse). Results Of the 1,846 participants, 44.9% were diagnosed with osteoporosis. The association between the social support network size and the incidence of osteoporosis was curvilinear in both bivariate and multivariate analyses. Having more people in one’s social support network size was associated with lower risk of osteoporosis until it reached around four. Increasing the social support network size beyond four, in contrast, was associated with a higher risk of osteoporosis. This association was contingent on the average intimacy level of the social network. At the highest average intimacy level (“extremely close”), increasing the number of social support network members from one to six was associated with linear decrease in the predicted probability of osteoporosis from 45% to 30%. However, at the lowest average intimacy level (“not very close”), the predicted probability of osteoporosis dramatically increased from 48% to 80% as the size of the social network increased from one to six. Conclusion Our results show that maintaining a large and intimate social support network is associated with a lower risk of osteoporosis among elderly Korean women, while a large but less-intimate social relationship is associated with a higher risk.

Aromatic Hybrid Foldamer with a Hydrophilic Helical Cavity Capable of Encapsulating Glucose

An indolocarbazole-naphthyridine hybrid oligomer capable of adopting a stable helical conformation was prepared, and its folding properties were thoroughly studied in the solid state and in solution. As a result of folding, a hydrophilic cavity was generated inside the helix wherein monosaccharides were able to be encapsulated in the order of glucose (9.6 × 104 M-1) > galactose (1.0 × 104 M-1) ≫ mannose (∼0) in 10% (v/v) DMSO/CH2Cl2.

Interactive Multi-View Video and View-Dependent Audio Under MPEG-21 DIA (Digital Item Adaptation)

In this paper, we propose an efficient multi-view system that transmits two view sequences for stereoscopic display and audio according to users request. The process for users preferences is integrated into MPEG-21 DIA. Multiview adaptation descriptors defined in DIA is used to deliver users preferences and device capabilities. Furthermore, we newly introduce multi-view descriptions that are represented in XML (extensible markup language) schema. Our proposed system also provides view-dependent audio according to user preferences. When a user changes a view from the center of the multi-view video to either the left or the right, audio signals are rendered to have directional information of viewers movement prior to being played out. Integrating audio with multi-view delivers more realistic perceptions.

Workload and variation aware thread scheduling for heterogeneous multi-processor

Optimal thread-to-core mapping is a critical issue for performance improvement in a heterogeneous multi-core processor that consists of out-of-order cores and in-order cores. Through the scheduling, threads with heavy workloads can be executed in an out-of-order core, whereas other threads can be concurrently executed in in-order cores. In addition, a core speed variation is deemed a factor to improve the performance; therefore, a scheduler has to handle the heterogeneity to derive optimal speedup. In this paper, we propose the workload aware and estimation-based dynamic thread scheduling for a heterogeneous multi-core. The scheduler profiles the workload of threads and classifies the threads as sequential or parallel threads and detects critical sections that are the bottleneck of the program. Based on the profiled information, the scheduler estimates the expected performance of each core. Core monitoring process measures the speed variation of each core concurrently. Using the information of threads and cores, the scheduler allocates the thread to the appropriate processor core dynamically.

Disparity weighted histogram-based object tracking for mobile robot systems

A vision-based real-time human detection and tracking capability is one of the key components of surveillance systems, human computer interfaces and monitoring systems. In this paper, we propose a method which uses color and disparity information obtained with a stereo camera. In order to achieve optimal performance with respect to detection or tracking of objects, it is better to consider multiple features together. We have developed a tracking method in which color and disparity information can be combined in a histogram. We used skin color and disparity distribution information to distinguish between different people. For human tracking, we propose a color histogram that is weighted by the disparity distribution of the target. The proposed method is simple and robust for moving camera environments and overcomes the drawbacks of conventional color histogram-based tracking methods. Experimental results show the robustness of the proposed method in environments with changing backgrounds and the tracking capabilities of targets which have similar color distributions as backgrounds or other targets. The proposed method can be used in real-time mobile robot applications.

Integrating multi-view transmission system into MPEG-21 stereoscopic and multi-view DIA (digital item adaptation)

As digital broadcasting technologies have been rapidly progressed, users expectations for realistic and interactive broadcasting services also have been increased. As one of such services, 3D multi-view broadcasting has received much attention recently. In general, all the view sequences acquired at the server are transmitted to the client. Then, the user can select a part of views or all the views according to display capabilities. However, this kind of system requires high processing power of the server as well as the client, thus posing a difficulty in practical applications. To overcome this problem, a relatively simple method is to transmit only two view-sequences requested by the client in order to deliver a stereoscopic video. In this system, effective communication between the server and the client is one of important aspects. In this paper, we propose an efficient multi-view system that transmits two view-sequences and their depth maps according to users request. The view selection process is integrated into MPEG-21 DIA (Digital Item Adaptation) so that our system is compatible to MPEG-21 multimedia framework. DIA is generally composed of resource adaptation and descriptor adaptation. It is one of merits that SVA (stereoscopic video adaptation) descriptors defined in DIA standard are used to deliver users preferences and device capabilities. Furthermore, multi-view descriptions related to multi-view camera and system are newly introduced. The syntax of the descriptions and their elements is represented in XML (eXtensible Markup Language) schema. If the client requests an adapted descriptor (e.g., view numbers) to the server, then the server sends its associated view sequences. Finally, we present a method which can reduce users visual discomfort that might occur while viewing stereoscopic video. This phenomenon happens when view changes as well as when a stereoscopic image produces excessive disparity caused by a large baseline between two cameras. To solve for the former, IVR (intermediate view reconstruction) is employed for smooth transition between two stereoscopic view sequences. As well, a disparity adjustment scheme is used for the latter. Finally, from the implementation of testbed and the experiments, we can show the valuables and possibilities of our system.