Crystal structure of ED-Eya2: insight into dual roles as a protein tyrosine phosphatase and a transcription factor

Eya proteins are transcription factors that play pivotal roles in organ formation during development by mediating interactions between Sine Oculis (SO) and Dachshund (DAC). Remarkably, the transcriptional activity of Eya proteins is regulated by a dephosphorylating activity within its Eya domain (ED). However, the molecular basis for the link between catalytic and transcriptional activities remains unclear. Here we report the first description of the crystal structure of the ED of human Eya2 (ED-Eya2), determined at 2.4-angstrom resolution. In stark contrast to other members of the haloacid dehalogenase (HAD) family to which ED-Eya2 belongs, the helix-bundle motif (HBM) is elongated along the back of the catalytic site. This not only results in a structure that accommodates large protein substrates but also positions the catalytic and the SO-interacting sites on opposite faces, which suggests that SO binding is not directly affected by catalytic function. Based on the observation that the DAC-binding site is located between the catalytic core and SO binding sites within ED-Eya2, we propose that catalytic activity can be translated to SO binding through DAC, which acts as a transcriptional switch. We also captured at two stages of reaction cycles-acyl-phosphate intermediate and transition state of hydrolysis step, which provided a detailed view of reaction mechanism. The ED-Eya2 structure defined here serves as a model for other members of the Eya family and provides a framework for understanding the role of Eya phosphatase mutations in disease.-Jung, S.-K., Jeong, D. G., Chung, S. J., Kim, J. H., Park, B. C., Tonks, N. K., Ryu, S. E., Kim, S. J.. Crystal structure of ED-Eya2: insight into dual roles as a protein tyrosine phosphatase and a transcription factor. FASEB J. 24, 560-569 (2010). www.fasebj.or

Techniques of Energy-Efficient VLSI Chip Design for High-Performance Computing

How to implement quality computing with the limited power budget is the key factor to move very large scale integration (VLSI) chip design forward. This work introduces various techniques of low power VLSI design used for state of art computing. From the viewpoint of power supply, conventional in-chip voltage regulators based on analog blocks bring the large overhead of both power and area to computational chips. Motivated by this, a digital based switchable pin method to dynamically regulate power at low circuit cost has been proposed to make computing to be executed with a stable voltage supply. For one of the widely used and time consuming arithmetic units, multiplier, its operation in logarithmic domain shows an advantageous performance compared to that in binary domain considering computation latency, power and area. However, the introduced conversion error reduces the reliability of the following computation (e.g. multiplication and division.). In this work, a fast calibration method suppressing the conversion error and its VLSI implementation are proposed. The proposed logarithmic converter can be supplied by dc power to achieve fast conversion and clocked power to reduce the power dissipated during conversion. Going out of traditional computation methods and widely used static logic, neuron-like cell is also studied in this work. Using multiple input floating gate (MIFG) metal-oxide semiconductor field-effect transistor (MOSFET) based logic, a 32-bit, 16-operation arithmetic logic unit (ALU) with zipped decoding and a feedback loop is designed. The proposed ALU can reduce the switching power and has a strong driven-in capability due to coupling capacitors compared to static logic based ALU. Besides, recent neural computations bring serious challenges to digital VLSI implementation due to overload matrix multiplications and non-linear functions. An analog VLSI design which is compatible to external digital environment is proposed for the network of long short-term memory (LSTM). The entire analog based network computes much faster and has higher energy efficiency than the digital one

Fluid Antenna System: New Insights on Outage Probability and Diversity Gain

To enable innovative applications and services, both industry and academia are exploring new technologies for sixth generation (6G) communications. One of the promising candidates is fluid antenna system (FAS). Unlike existing systems, FAS is a novel communication technology where its antenna can freely change its position and shape within a given space. Compared to the traditional systems, this unique capability has the potential of providing higher diversity and interference-free communications. Nevertheless, the performance limits of FAS remain unclear as its system properties are difficult to analyze. To address this, we approximate the outage probability and diversity gain of FAS in closed-form expressions. We then propose a suboptimal FAS with N * ports, where a significant gain can be obtained over FAS with N * - 1 ports whilst FAS with N * + 1 ports only yields marginal improvement over the proposed suboptimal FAS. In this paper, we also provide analytical and simulation results to unfold the key factors that affect the performance of FAS. Limited to systems with one active radio frequency (RF)-chain, we show that the proposed suboptimal FAS outperforms single-antenna (SISO) system and selection combining (SC) system in terms of outage probability. Interestingly, when the given space is λ/2, the outage probability of the proposed suboptimal FAS with one active RF-chain achieves near to that of the maximal ratio combining (MRC) system with multiple active RF-chains

발전국가론에서 본 한국 공적개발원조정책의 재조명

학위논문 (석사)-- 서울대학교 국제대학원 국제학과, 2017. 8. Kim, Taekyoon.Since 2010, South Korea (hereafter Korea) has been a full-fledged member of the Organisation for Economic Cooperation and Developments (OECD) Development Assistance Committee (DAC) with which it has made the successful transition from an aid recipient to an aid-donor country. Measured by its volume, Korea is counted as a substantial contributor of Official Development Assistance (ODA) among OECD DAC members and has promised to make continuous efforts to improve its ODA policies so as to adhere to the OECD DAC standards. Nevertheless, although Koreas ODA in terms of quantity has been on a constant increase and Korea has made continuous efforts to improve its aid effectiveness, it has been criticized for its low quality and policy decisions have often not translated into actual implementation. Koreas ODA agenda not only suggests a strong economic interest in giving aid, but also contains elements that strongly reflect Koreas own experience as a developmental state. Based upon a historical analysis of Koreas ODA decision-making process and through the lens of the developmental state thesis, particularly with regards to the state-society relations, this research explores why Korea has continuously struggled to implement a more effective and coherent ODA policy framework vis-à-vis its ambitious claims. This research shows that Koreas developmentalist mindset, which originated during its heyday as a developmental state, is still closely embedded in Koreas ODA policy decision-making process which determines much of Koreas behaviour as a donor of foreign aid.I. Introduction 1 1. Literature Review 5 2. Research Problem 9 II. Analytical Framework 10 1. Theoretical Framework 10 1.1. Embedded Autonomy (Evans 1995) 10 1.2. Developmental citizenship (Chang 2007, 2012) 12 2. Methodology 16 III. Making the developmental success story: Identity formation through state-society ties-based growth (1960-1980s) 18 IV. Securing the story: ODA as a replication of domestic developmental politics (1987-2004) 26 V. Making the story marketable: new benchmark-driven ODA (2005-2009) 35 VI. Institutionalising and selling the story back: quasi-modern ODA cut across selective state-society relations (2010+) 44 1. State power and structure remains 46 1.1. Top-down decision-making process with selective civil society engagement 46 1.2. Keeping the budgeting power in the hands of powerful MOSF, the former privileged EPB 48 1.3. Selling Koreas development knowledge: Knowledge Sharing Program (KSP) 52 1.4. The salient developmental ghost: Korean Saemaul Undong (New Village Movement) 56 2. Persistence of state-market symbiosis for strategic interests 59 2.1. Opening the back door for private firms: Public Private Partnership (PPP) 59 2.2. Keeping private firms happy: Tied aid and project-aid 62 2.3. Tapping Asia and resource-rich countries: Geographical priorities 64 2.4. The growth-centric playground for energy firms: Green Growth and Green ODA 67 VII. Conclusion: Breaking the story or continue growing on it? 73 List of References 77 Abstract in Korean (국문초록) 83Maste