677 research outputs found
์ฌ๋ฌผ์ธํฐ๋ท์ ์ํ ๋ฌด์ ์ค๋ด ์ธก์ ์๊ณ ๋ฆฌ์ฆ
ํ์๋
ผ๋ฌธ(๋ฐ์ฌ) -- ์์ธ๋ํ๊ต๋ํ์ : ๊ณต๊ณผ๋ํ ์ ๊ธฐยท์ ๋ณด๊ณตํ๋ถ, 2022.2. ๊น์ฑ์ฒ .์ค๋ด ์์น ๊ธฐ๋ฐ ์๋น์ค๋ ์ค๋งํธํฐ์ ์ด์ฉํ ์ค๋ด์์์ ๊ฒฝ๋ก์๋ด, ์ค๋งํธ ๊ณต์ฅ์์์ ์์ ๊ด๋ฆฌ, ์ค๋ด ๋ก๋ด์ ์์จ์ฃผํ ๋ฑ ๋ง์ ๋ถ์ผ์ ์ ๋ชฉ๋ ์ ์์ผ๋ฉฐ, ์ฌ๋ฌผ์ธํฐ๋ท ์์ฉ์๋ ํ์์ ์ธ ๊ธฐ์ ์ด๋ค. ๋ค์ํ ์์น ๊ธฐ๋ฐ ์๋น์ค๋ฅผ ๊ตฌํํ๊ธฐ ์ํด์๋ ์ ํํ ์์น ์ ๋ณด๊ฐ ํ์ํ๋ฉฐ, ์ ํฉํ ๊ฑฐ๋ฆฌ ๋ฐ ์์น๋ฅผ ์ถ์ ๊ธฐ์ ์ด ํต์ฌ์ ์ด๋ค. ์ผ์ธ์์๋ ์์ฑํญ๋ฒ์์คํ
์ ์ด์ฉํด์ ์์น ์ ๋ณด๋ฅผ ํ๋ํ ์ ์๋ค.
๋ณธ ํ์๋
ผ๋ฌธ์์๋ ์์ดํ์ด ๊ธฐ๋ฐ ์ธก์ ๊ธฐ์ ์ ๋ํด ๋ค๋ฃฌ๋ค. ๊ตฌ์ฒด์ ์ผ๋ก, ์ ํ์ ์ ํธ ์ธ๊ธฐ ๋ฐ ๋๋ฌ ์๊ฐ์ ์ด์ฉํ ์ ๋ฐํ ์ค๋ด ์์น ์ถ์ ์ ์ํ ์ธ ๊ฐ์ง ๊ธฐ์ ์ ๋ํด ๋ค๋ฃฌ๋ค. ๋จผ์ , ๋น๊ฐ์๊ฒฝ๋ก ํ๊ฒฝ์์์ ๊ฑฐ๋ฆฌ ์ถ์ ์ ํ๋๋ฅผ ํฅ์์์ผ ๊ฑฐ๋ฆฌ ๊ธฐ๋ฐ ์ธก์์ ์ ํ๋๋ฅผ ํฅ์์ํค๋ ํ์ด๋ธ๋ฆฌ๋ ์๊ณ ๋ฆฌ์ฆ์ ์ ์ํ๋ค. ์ ์ํ ์๊ณ ๋ฆฌ์ฆ์๋์ผ ๋ฐด๋ ๋์ญ์ ์ ํธ์ธ๊ธฐ๋ฅผ ๊ฐ์๋์ ์ธก์ ํ์ฌ ๊ฑฐ๋ฆฌ ๊ธฐ๋ฐ ์ธก์ ๊ธฐ๋ฒ์ ์ ์ฉํ ๋, ๊ฑฐ๋ฆฌ ์ถ์ ๋ถ ๋จ๊ณ๋ง์ ๋ฐ์ดํฐ ๊ธฐ๋ฐ ํ์ต์ ์ด์ฉํ ๊น์ ์ ๊ฒฝ๋ง ํ๊ท ๋ชจ๋ธ๋ก ๋์ฒดํ ๋ฐฉ์์ด๋ค. ์ ์ ํ ํ์ต๋ ๊น์ ํ๊ท ๋ชจ๋ธ์ ์ฌ์ฉ์ผ๋ก ๋น๊ฐ์๊ฒฝ๋ก ํ๊ฒฝ์์ ๋ฐ์ํ๋ ๊ฑฐ๋ฆฌ ์ถ์ ์ค์ฐจ๋ฅผ ํจ๊ณผ์ ์ผ๋ก ๊ฐ์์ํฌ ์ ์์ผ๋ฉฐ, ๊ฒฐ๊ณผ์ ์ผ๋ก ์์น ์ถ์ ์ค์ฐจ ๋ํ ๊ฐ์์์ผฐ๋ค. ์ ์ํ ๋ฐฉ๋ฒ์ ์ค๋ด ๊ด์ ์ถ์ ๊ธฐ๋ฐ ๋ชจ์์คํ์ผ๋ก ํ๊ฐํ์ ๋, ๊ธฐ์กด ๊ธฐ๋ฒ๋ค์ ๋นํด์ ์์น ์ถ์ ์ค์ฐจ๋ฅผ ์ค๊ฐ๊ฐ์ ๊ธฐ์ค์ผ๋ก 22.3% ์ด์ ์ค์ผ ์ ์์์ ๊ฒ์ฆํ๋ค. ์ถ๊ฐ์ ์ผ๋ก, ์ ์ํ ๋ฐฉ๋ฒ์ ์ค๋ด์์์ AP ์์น๋ณํ ๋ฑ์ ๊ฐ์ธํจ์ ํ์ธํ๋ค.
๋ค์์ผ๋ก, ๋ณธ ๋
ผ๋ฌธ์์๋ ๋น๊ฐ์๊ฒฝ๋ก์์ ๋จ์ผ ๋์ญ ์์ ์ ํธ์ธ๊ธฐ๋ฅผ ์ธก์ ํ์ ๋ ๋น๊ฐ์๊ฒฝ๋ก๊ฐ ๋ง์ ์ค๋ด ํ๊ฒฝ์์ ์์น ์ถ์ ์ ํ๋๋ฅผ ๋์ด๊ธฐ ์ํ ๋ฐฉ์์ ์ ์ํ๋ค. ๋จ์ผ ๋์ญ ์์ ์ ํธ์ธ๊ธฐ๋ฅผ ์ด์ฉํ๋ ๋ฐฉ์์ ๊ธฐ์กด์ ์ด์ฉ๋๋ ์์ดํ์ด, ๋ธ๋ฃจํฌ์ค, ์ง๋น ๋ฑ์ ๊ธฐ๋ฐ์์ค์ ์ฝ๊ฒ ์ ์ฉ๋ ์ ์๊ธฐ ๋๋ฌธ์ ๋๋ฆฌ ์ด์ฉ๋๋ค. ํ์ง๋ง ์ ํธ ์ธ๊ธฐ์ ๋จ์ผ ๊ฒฝ๋ก์์ค ๋ชจ๋ธ์ ์ด์ฉํ ๊ฑฐ๋ฆฌ ์ถ์ ์ ์๋นํ ์ค์ฐจ๋ฅผ ์ง๋
์ ์์น ์ถ์ ์ ํ๋๋ฅผ ๊ฐ์์ํจ๋ค. ์ด๋ฌํ ๋ฌธ์ ์ ์์ธ์ ๋จ์ผ ๊ฒฝ๋ก์์ค ๋ชจ๋ธ๋ก๋ ์ค๋ด์์์ ๋ณต์กํ ์ ํ ์ฑ๋ ํน์ฑ์ ๋ฐ์ํ๊ธฐ ์ด๋ ต๊ธฐ ๋๋ฌธ์ด๋ค. ๋ณธ ์ฐ๊ตฌ์์๋ ์ค๋ด ์์น ์ถ์ ์ ์ํ ๋ชฉ์ ์ผ๋ก, ์ค์ฒฉ๋ ๋ค์ค ์ํ ๊ฒฝ๋ก ๊ฐ์ ๋ชจ๋ธ์ ์๋กญ๊ฒ ์ ์ํ๋ค. ์ ์ํ ๋ชจ๋ธ์ ๊ฐ์๊ฒฝ๋ก ๋ฐ ๋น๊ฐ์๊ฒฝ๋ก์์์ ์ฑ๋ ํน์ฑ์ ๊ณ ๋ คํ์ฌ ์ ์ฌ์ ์ธ ํ๋ณด ์ํ๋ค์ ์ง๋๋ค. ํ ์๊ฐ์ ์์ ์ ํธ ์ธ๊ธฐ ์ธก์ ์น์ ๋ํด ๊ฐ ๊ธฐ์ค ๊ธฐ์ง๊ตญ๋ณ๋ก ์ต์ ์ ๊ฒฝ๋ก์์ค ๋ชจ๋ธ ์ํ๋ฅผ ๊ฒฐ์ ํ๋ ํจ์จ์ ์ธ ๋ฐฉ์์ ์ ์ํ๋ค. ์ด๋ฅผ ์ํด ๊ธฐ์ง๊ตญ๋ณ ๊ฒฝ๋ก์์ค๋ชจ๋ธ ์ํ์ ์กฐํฉ์ ๋ฐ๋ฅธ ์ธก์ ๊ฒฐ๊ณผ๋ฅผ ํ๊ฐํ ์งํ๋ก์ ๋น์ฉํจ์๋ฅผ ์ ์ํ์๋ค. ๊ฐ ๊ธฐ์ง๊ตญ๋ณ ์ต์ ์ ์ฑ๋ ๋ชจ๋ธ์ ์ฐพ๋๋ฐ ํ์ํ ๊ณ์ฐ ๋ณต์ก๋๋ ๊ธฐ์ง๊ตญ ์์ ์ฆ๊ฐ์ ๋ฐ๋ผ ๊ธฐํ๊ธ์์ ์ผ๋ก ์ฆ๊ฐํ๋๋ฐ, ์ ์ ์๊ณ ๋ฆฌ์ฆ์ ์ด์ฉํ ํ์์ ์ ์ฉํ์ฌ ๊ณ์ฐ๋์ ์ต์ ํ์๋ค. ์ค๋ด ๊ด์ ์ถ์ ๋ชจ์์คํ์ ํตํ ๊ฒ์ฆ๊ณผ ์ค์ธก ๊ฒฐ๊ณผ๋ฅผ ์ด์ฉํ ๊ฒ์ฆ์ ์งํํ์์ผ๋ฉฐ, ์ ์ํ ๋ฐฉ์์ ์ค์ ์ค๋ด ํ๊ฒฝ์์ ๊ธฐ์กด์ ๊ธฐ๋ฒ๋ค์ ๋นํด ์์น ์ถ์ ์ค์ฐจ๋ฅผ ์ฝ 31% ๊ฐ์์์ผฐ์ผ๋ฉฐ ํ๊ท ์ ์ผ๋ก 1.92 m ์์ค์ ์ ํ๋๋ฅผ ๋ฌ์ฑํจ์ ํ์ธํ๋ค.
๋ง์ง๋ง์ผ๋ก FTM ํ๋กํ ์ฝ์ ์ด์ฉํ ์ค๋ด ์์น ์ถ์ ์๊ณ ๋ฆฌ์ฆ์ ๋ํด ์ฐ๊ตฌํ์๋ค. ์ค๋งํธํฐ์ ๋ด์ฅ ๊ด์ฑ ์ผ์์ ์์ดํ์ด ํต์ ์์ ์ ๊ณตํ๋ FTM ํ๋กํ ์ฝ์ ํตํ ๊ฑฐ๋ฆฌ ์ถ์ ์ ์ด์ฉํ์ฌ ์ค๋ด์์ ์ฌ์ฉ์์ ์์น๋ฅผ ์ถ์ ํ ์ ์๋ค. ํ์ง๋ง ์ค๋ด์ ๋ณต์กํ ๋ค์ค๊ฒฝ๋ก ํ๊ฒฝ์ผ๋ก ์ธํ ํผํฌ ๊ฒ์ถ ์คํจ๋ ๊ฑฐ๋ฆฌ ์ธก์ ์น์ ํธํฅ์ฑ์ ์ ๋ฐํ๋ค. ๋ํ ์ฌ์ฉํ๋ ๋๋ฐ์ด์ค์ ์ข
๋ฅ์ ๋ฐ๋ผ ์์์น ๋ชปํ ๊ฑฐ๋ฆฌ ์ค์ฐจ๊ฐ ๋ฐ์ํ ์์๋ค. ๋ณธ ๋
ผ๋ฌธ์์๋ ์ค์ ํ๊ฒฝ์์ FTM ๊ฑฐ๋ฆฌ ์ถ์ ์ ์ด์ฉํ ๋ ๋ฐ์ํ ์ ์๋ ์ค์ฐจ๋ค์ ๊ณ ๋ คํ๊ณ ์ด๋ฅผ ๋ณด์ํ๋ ๋ฐฉ์์ ๋ํด ์ ์ํ๋ค. ํ์ฅ ์นผ๋ง ํํฐ์ ๊ฒฐํฉํ์ฌ FTM ๊ฒฐ๊ณผ๋ฅผ ์ฌ์ ํํฐ๋ง ํ์ฌ ์ด์๊ฐ์ ์ ๊ฑฐํ๊ณ , ๊ฑฐ๋ฆฌ ์ธก์ ์น์ ํธํฅ์ฑ์ ์ ๊ฑฐํ์ฌ ์์น ์ถ์ ์ ํ๋๋ฅผ ํฅ์์ํจ๋ค. ์ค๋ด์์์ ์คํ ๊ฒฐ๊ณผ ์ ์ํ ์๊ณ ๋ฆฌ์ฆ์ ๊ฑฐ์น ์ธก์ ์น์ ํธํฅ์ฑ์ ์ฝ 44-65% ๊ฐ์์์ผฐ์ผ๋ฉฐ ์ต์ข
์ ์ผ๋ก ์ฌ์ฉ์์ ์์น๋ฅผ ์๋ธ๋ฏธํฐ๊ธ์ผ๋ก ์ถ์ ํ ์ ์์์ ๊ฒ์ฆํ๋ค.Indoor location-based services (LBS) can be combined with various applications such as indoor navigation for smartphone users, resource management in smart factories, and autonomous driving of robots. It is also indispensable for Internet of Things (IoT) applications. For various LBS, accurate location information is essential. Therefore, a proper ranging and positioning algorithm is important. For outdoors, the global navigation satellite system (GNSS) is available to provide position information. However, the GNSS is inappropriate indoors owing to the issue of the blocking of the signals from satellites. It is necessary to develop a technology that can replace GNSS in GNSS-denied environments. Among the various alternative systems, the one of promising technology is to use a Wi-Fi system that has already been applied to many commercial devices, and the infrastructure is in place in many regions.
In this dissertation, Wi-Fi based indoor localization methods are presented. In the specific, I propose the three major issues related to accurate indoor localization using received signal strength (RSS) and fine timing measurement (FTM) protocol in the 802.11 standard for my dissertation topics.
First, I propose a hybrid localization algorithm to boost the accuracy of range-based localization by improving the ranging accuracy under indoor non-line-of-sight (NLOS) conditions. I replaced the ranging part of the rule-based localization method with a deep regression model that uses data-driven learning with dual-band received signal strength (RSS). The ranging error caused by the NLOS conditions was effectively reduced by using the deep regression method. As a consequence, the positioning error could be reduced under NLOS conditions. The performance of the proposed method was verified through a ray-tracing-based simulation for indoor spaces. The proposed scheme showed a reduction in the positioning error of at least 22.3% in terms of the median root mean square error.
Next, I study on positioning algorithm that considering NLOS conditions for each APs, using single band RSS measurement. The single band RSS information is widely used for indoor localization because they can be easily implemented by using existing infrastructure like Wi-Fi, Blutooth, or Zigbee. However, range estimation with a single pathloss model produces considerable errors, which degrade the positioning performance. This problem mainly arises because the single pathloss model cannot reflect diverse indoor radio wave propagation characteristics. In this study, I develop a new overlapping multi-state model to consider multiple candidates of pathloss models including line-of-sight (LOS) and NLOS states, and propose an efficient way to select a proper model for each reference node involved in the localization process. To this end, I formulate a cost function whose value varies widely depending on the choice of pathloss model of each access point. Because the computational complexity to find an optimal channel model for each reference node exponentially increases with the number of reference nodes, I apply a genetic algorithm to significantly reduce the complexity so that the proposed method can be executed in real-time. Experimental validations with ray-tracing simulations and RSS measurements at a real site confirm the improvement of localization accuracy for Wi-Fi in indoor environments. The proposed method achieves up to 1.92~m mean positioning error under a practical indoor environment and produces a performance improvement of 31.09\% over the benchmark scenario.
Finally, I investigate accurate indoor tracking algorithm using FTM protocol in this dissertation.
By using the FTM ranging and the built-in sensors in a smartphone, it is possible to track the user's location in indoor. However, the failure of first peak detection due to the multipath effect causes a bias in the FTM ranging results in the practical indoor environment. Additionally, the unexpected ranging error dependent on device type also degrades the indoor positioning accuracy. In this study, I considered the factors of ranging error in the FTM protocol in practical indoor environment, and proposed a method to compensate ranging error. I designed an EKF-based tracking algorithm that adaptively removes outliers from the FTM result and corrects bias to increase positioning accuracy. The experimental results verified that the proposed algorithm reduces the average ofthe ranging bias by 43-65\% in an indoor scenarios, and can achieve the sub-meter accuracy in average route mean squared error of user's position in the experiment scenarios.Abstract i
Contents iv
List of Tables vi
List of Figures vii
1 INTRODUCTION 1
2 Hybrid Approach for Indoor Localization Using Received Signal Strength
of Dual-BandWi-Fi 6
2.1 Motivation 6
2.2 Preliminary 8
2.3 System model 11
2.4 Proposed Ranging Method 13
2.5 Performance Evaluation 16
2.5.1 Ray-Tracing-Based Simulation 16
2.5.2 Analysis of the Ranging Accuracy 21
2.5.3 Analysis of the Neural Network Structure 25
2.5.4 Analysis of Positioning Accuracy 26
2.6 Summary 29
3 Genetic Algorithm for Path Loss Model Selection in Signal Strength Based
Indoor Localization 31
3.1 Motivation 31
3.2 Preliminary 34
3.2.1 RSS-based Ranging Techniques 35
3.2.2 Positioning Technique 37
3.3 Proposed localization method 38
3.3.1 Localization Algorithm with Overlapped Multi-State Path Loss
Model 38
3.3.2 Localization with Genetic Algorithm-Based Search 41
3.4 Performance evaluation 46
3.4.1 Numerical simulation 50
3.4.2 Experimental results 56
3.5 Summary 60
4 Indoor User Tracking with Self-calibrating Range Bias Using FTM Protocol
62
4.1 Motivation 62
4.2 Preliminary 63
4.2.1 FTM ranging 63
4.2.2 PDR-based trajectory estimation 65
4.3 EKF design for adaptive compensation of ranging bias 66
4.4 Performance evaluation 69
4.4.1 Experimental scenario 69
4.4.2 Experimental results 70
4.5 Summary 75
5 Conclusion 76
Abstract (In Korean) 89๋ฐ
Clinical Characteristics of Monomorphic Post-transplant Lymphoproliferative Disorders
Post-transplant lymphoproliferative disorders (PTLD) are a heterogeneous group of lymphoproliferative disorders associated with immunosuppression and Epstein-Barr virus infection. PTLD is classified into three major categories: early lesions, polymorphic PTLD, and monomorphic PTLD. The majority of monomorphic PTLD cases are non-Hodgkin's lymphoma of B-cell origin. This retrospective study was conducted to investigate the incidence, clinical manifestation, treatment, and outcomes of monomorphic PTLD among 5,817 recipients of solid organ or allogeneic hematopoietic stem cell transplantation from five institutions. Fourteen patients with monomorphic PTLD were identified (male:female 11:3; median age 42.6 yr, range 24-60). The overall incidence rate was 0.24%. The most common disease type was diffuse large B cell lymphoma (n=7). The median time between the transplant and diagnosis of PTLD was 85.8 months. However, all cases of PTLD after allogeneic hematopoietic stem cell transplantation occurred within 1 yr after transplantation. Ten of the 14 patients had EBV-positive tumor. Fourteen patients received combination systemic chemotherapy and four patients were treated with radiation therapy. Ten patients achieved a complete response (CR) and two patients a partial response (PR). The median follow-up period for surviving patients was 36.6 months. Nine patients remain alive (eight CR, one PR). Nine of 11 solid organ transplantations preserved graft function. The present study indicates a lower incidence rate and a longer median time before the development of PTLD than those of previous reports. Careful monitoring was needed after allogeneic hematopoietic stem cell transplantation for PTLD
To the Edge of M87 and Beyond: Spectroscopy of Intracluster Globular Clusters and Ultra Compact Dwarfs in the Virgo Cluster
We present the results from a wide-field spectroscopic survey of globular
clusters (GCs) in the Virgo Cluster. We obtain spectra for 201 GCs and 55
ultracompact dwarfs (UCDs) using the Hectospec on the Multiple Mirror
Telescope, and derive their radial velocities. We identify 46 genuine
intracluster GCs (IGCs), not associated with any Virgo galaxies, using the 3D
GMM test on the spatial and radial velocity distribution.They are located at
the projected distance 200 kpc R 500 kpc from the center
of M87. The radial velocity distribution of these IGCs shows two peaks, one at
= 1023 km s associated with the Virgo main body, and another
at = 36 km s associated with the infalling structure. The
velocity dispersion of the IGCs in the Virgo main body is 314 km s, which is smoothly connected to the velocity dispersion
profile of M87 GCs, but much lower than that of dwarf galaxies in the same
survey field, 608 km s. The UCDs are more
centrally concentrated on massive galaxies, M87, M86, and M84. The radial
velocity dispersion of the UCD system is much smaller than that of dwarf
galaxies. Our results confirm the large-scale distribution of Virgo IGCs
indicated by previous photometric surveys. The color distribution of the
confirmed IGCs shows a bimodality similar to that of M87 GCs. This indicates
that most IGCs are stripped off from dwarf galaxies and some from massive
galaxies in the Virgo.Comment: 19 pages, 20 figures, 8 tables, accepted for publication in Ap
A search for exoplanets around north circumpolar stars. VII. Detection of planetary companion orbiting the largest host star HD 18438
We have been conducting a exoplanet search survey using Bohyunsan Observatory
Echelle Spectrograph (BOES) for the last 18 years. We present the detection of
exoplanet candidate in orbit around HD 18438 from high-precision radial
velocity (RV) mesurements. The target was already reported in 2018 (Bang et al.
2018). They conclude that the RV variations with a period of 719 days are
likely to be caused by the pulsations because the Lomb-Scargle periodogram of
HIPPARCOS photometric and Ha EW variations for HD 18438 show peaks with periods
close to that of RV variations and there were no correlations between bisectors
and RV measurements. However, the data were not sufficient to reach a firm
conclusion. We obtained more RV data for four years. The longer time baseline
yields a more accurate determination with a revised period of 803 +/- 5 days
and the planetary origin of RV variations with a minimum planetary companion
mass of 21 +/- 1 MJup. Our current estimate of the stellar parameters for HD
18438 makes it currently the largest star with a planetary companion.Comment: 6 pages, 4 figures, Accept to the Journal of the Korean Astronomical
Societ
UKIRT Widefield Infrared Survey for Fe+
The United Kingdom Infrared Telescope (UKIRT)Widefield Infrared Survey for Fe+ (UWIFE) is a 180 deg2 imaging survey of the first Galactic quadrant (7รยฐ < l < 62รยฐ |b| <1รยฐ.5) that uses a narrow-band filter centred on the [Fe II] 1.644-รยผm emission line. The [Fe II] 1.644-รยผm emission is a good tracer of dense, shock-excited gas, and the survey will probe violent environments around stars: star-forming regions, evolved stars, and supernova remnants, among others. The UWIFE survey is designed to complement the existing UKIRTW idefield Infrared Survey for H2 (UWISH2). The survey will also complement existing broad-band surveys. The observed images have a nominal 5ร? detection limit of 18.7 mag for point sources, with a median seeing of 0.83 arcsec. For extended sources, we estimate a surface brightness limit of 8.1 ร? 10-20 W m-2 arcsec-2. In this paper, we present an overview and some preliminary results of this survey. รยฉ 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
Evaluation of therapeutic effects of natural killer (NK) cell-based immunotherapy in mice using in vivo apoptosis bioimaging with a caspase-3 sensor
Natural killer (NK) cellรข based immunotherapy is a promising strategy for cancer treatment, and caspaseรข 3 is an important effector molecule in NK cellรข mediated apoptosis in cancers. Here, we evaluated the antitumor effects of NK cellรข based immunotherapy by serial noninvasive imaging of apoptosis using a caspaseรข 3 sensor in mice with human glioma xenografts. Human glioma cells expressing both a caspaseรข 3 sensor as a surrogate marker for caspaseรข 3 activation and Renilla luciferase (Rluc) as a surrogate marker for cell viability were established and referred to as D54รข CR cells. Human NK92 cells were used as effector cells. Treatment with NK92 cells resulted in a timeรข and effector numberรข dependent increase in bioluminescence imaging (BLI) activity of the caspaseรข 3 sensor in D54รข CR cells in vitro. Caspaseรข 3 activation by NK92 treatment was blocked by Zรข VAD treatment in D54รข CR cells. Transfusion of NK92 cells induced an increase of the BLI signal by caspaseรข 3 activation in a doseรข and timeรข dependent manner in D54รข CR tumorรข bearing mice but not in PBSรข treated mice. Accordingly, sequential BLI with the Rluc reporter gene revealed marked retardation of tumor growth in the NK92รข treatment group but not in the PBSรข treatment group. These data suggest that noninvasive imaging of apoptosis with a caspaseรข 3 sensor can be used as an effective tool for evaluation of therapeutic efficacy as well as for optimization of NK cellรข based immunotherapy.รข Lee, H. W., Singh, T. D., Lee, S.รข W., Ha, J.รข H., Rehemtulla, A., Ahn, B.รข C., Jeon, Y.รข H., Lee, J. Evaluation of therapeutic effects of natural killer (NK) cellรข based immunotherapy in mice using in vivo apoptosis bioimaging with a caspaseรข 3 sensor. FASEB J. 28, 2932รข 2941 (2014). www.fasebj.orgPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154541/1/fsb2fj13243014.pd
Microlensing Detections of Planets in Binary Stellar Systems
We demonstrate that microlensing can be used for detecting planets in binary
stellar systems. This is possible because in the geometry of planetary binary
systems where the planet orbits one of the binary component and the other
binary star is located at a large distance, both planet and secondary companion
produce perturbations at a common region around the planet-hosting binary star
and thus the signatures of both planet and binary companion can be detected in
the light curves of high-magnification lensing events. We find that identifying
planets in binary systems is optimized when the secondary is located in a
certain range which depends on the type of the planet. The proposed method can
detect planets with masses down to one tenth of the Jupiter mass in binaries
with separations <~ 100 AU. These ranges of planet mass and binary separation
are not covered by other methods and thus microlensing would be able to make
the planetary binary sample richer.Comment: 5 pages, two figures in JPG forma
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