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Coupled transcription and translation processes in bacteria cause indiscriminate translation of intact and truncated messenger RNAs, inevitably generating nonfunctional polypeptides. Here, we devised a synthetic protein quality control (ProQC) system that enables translation only when both ends of mRNAs are present and followed by circularization based on sequence-specific RNA-RNA hybridization. We demonstrate that the ProQC system dramatically improved the fraction of full-length proteins among all synthesized polypeptides by selectively translating intact mRNA and reducing abortive translation. As a result, full-length protein synthesis increased up to 2.5-fold without changing the transcription or translation efficiency. Furthermore, we applied the ProQC system for 3-hydroxypropionic acid, violacein and lycopene production by ensuring full-length expression of enzymes in biosynthetic pathways, resulting in 1.6- to 2.3-fold greater biochemical production. We believe that our ProQC system can be universally applied to improve not only the quality of recombinant protein production but also efficiencies of metabolic pathways.

Economic indicators are a factor that affects air cargo volume. This study analyzes the different factors affecting air cargo volume by each Chinese cities according to the main characteristics. The purpose of this study is to help companies related to China, airlines, and other stakeholders predict and prepare for the fluctuations in air cargo volume and make optimal decisions. To this end, 20 economic data were used, and the entire data was reduced to 5 dimensions through factor analysis to build a dataset necessary and evaluated the influencing factors by multi regression. The result shows that Macro-Economic Indicators, Production/Service indicators are significant for every cities and Chinese manufacture/Customer indicators, Korean manufacture/Oil Price indicators, Trade/Current indicators are significant for each other city. All adjusted R2 values are high enough to explain our model and the result showed excellent performance in terms of analyzing the different factors which affects air cargo volume. If companies that are currently doing business with China can identify factors affecting China's cargo volume, they can be flexible in response to changes in plans such as plans to enter China, production plans and inventory management, and marketing strategies, which can be of great help in terms of corporate operations.

Microbial conversion to generate value-added chemicals from diverse biomass is one of the keystones of energy biotechnology. Programmable synthetic biology tools offer versatile, standardized options for developing microbial cell factories. These tools thus can be reprogrammed in a user-defined manner for flexible wiring of stimuli and response, highly efficient genome engineering, and extensive perturbation of metabolic flux and genetic circuits. They also can be modularly assembled to construct elaborate and unprecedented biological systems with unique features. This review highlights recent advances in programmable synthetic biology tools based on biosensors, CRISPR-Cas, and RNA devices for developing microbial cell factories that have the potential to be utilized for energy biotechnology.

Proper carbon flux distribution between cell growth and production of a target compound is important for biochemical production because improper flux reallocation inhibits cell growth, thus adversely affecting production yield. Here, using a synthetic biosensor to couple production of a specific metabolite with cell growth, we spontaneously evolve cells under the selective condition toward the acquisition of genotypes that optimally reallocate cellular resources. Using 3-hydroxypropionic acid (3-HP) production from glycerol in Escherichia coli as a model system, we determine that mutations in the conserved regions of proteins involved in global transcriptional regulation alter the expression of several genes associated with central carbon metabolism. These changes rewire central carbon flux toward the 3-HP production pathway, increasing 3-HP yield and reducing acetate accumulation by alleviating overflow metabolism. Our study provides a perspective on adaptive laboratory evolution (ALE) using synthetic biosensors, thereby supporting future efforts in metabolic pathway optimization., This research was supported by the C1 Gas Refinery Program (NRF-2018M3D3A1A01055754 and NRF-2015M3D3A1A01064882), the Global Research Laboratory Program (NRF-2016K1A1A2912829), and the Bio & Medical Technology Development Program (NRF-2018M3A9H3020459) through the National Research Foundation of Korea (NRF of Korea), funded by the Ministry of Science and ICT (MSIT). S.W.S. is partially supported by the Creative-Pioneering Researchers Program through Seoul National University (SNU).

Long-term space missions affect the gut microbiome of astronauts, especially the viability of some pathogens. Probiotics may be an effective solution for the management of gut microbiomes, but there is a lack of studies regarding the physiology of probiotics in microgravity. Here, we investigated the effects of microgravity on the probiotic Escherichia coli Nissle 1917 (EcN) by comparing transcriptomic data during exponential and stationary growth phases under simulated microgravity and normal gravity. Microgravity conditions affected several physiological features of EcN, including its growth profile, biofilm formation, stress responses, metal ion transport/utilization, and response to carbon starvation. We found that some changes, such as decreased adhesion ability and acid resistance, may be disadvantageous to EcN relative to gut pathogens under microgravity, indicating the need to develop probiotics optimized for space flight.

Echiura is one of the most intriguing major subgroups of phylum Annelida because, unlike most other annelids, echiuran adults lack metameric body segmentation. Urechis unicinctus lives in U-shape burrows of soft sediments. Little is known about the molecular mechanisms underlying the development of U. unicinctus. Herein, we overviewed the developmental process from zygote to juvenile U. unicinctus using immunohistochemistry and F-actin staining for the nervous and muscular systems, respectively. Through F-actin staining, we found that muscle fibers began to form in the trochophore phase and that muscles for feeding were produced first. Subsequently, in the segmentation larval stage, the transversal muscle was formed in the shape of a ring in an anterior-to-posterior direction with segment formation, as well as a ventromedian muscle for the formation of a ventral nerve cord. After that, many muscle fibers were produced along the entire body and formed the worm-shaped larva. Finally, we investigated the spatiotemporal expression of Uun_st-mhc, Uun_troponin I, Uun_calponin, and Uun_twist genes found in U. unicinctus. During embryonic development, the striated and smooth muscle genes were co-expressed in the same region. However, the adult body wall muscles showed differential gene expression of each muscle layer. The results of this study will provide the basis for the understanding of muscle differentiation in Echiura.

[연구목적] 본 연구는 부동층 배분 방식이 선거여론조사의 예측오차에 미치는 영향을 전국동시지방선거 여론조사 자료를 사용하여 분석하였다. [연구방법] paired t－test, Wilcox 부호순위 검정, Pearson 상관분석을 이용하여 평균 예측오차 차이의 통계적 유의성을 검정하였으며, 회귀분석을 이용하여 부동층 배분 방식별 예측오차 차이에 영향을...

An M-to-1 conveyor system consists of multiple upstream conveyors and a single downstream conveyor. In this paper, we investigate the paint batching problem on M-to-1 conveyor systems with the objective of minimizing setup costs. Our research is motivated by a vehicle re-sequencing problem at a major Korean automotive manufacturer. Setup costs are incurred when two consecutive jobs in the downstream conveyor do not share the same feature. Re-sequencing flexibility is limited by the precedence relationship among jobs in the upstream conveyors. First, we develop a mixed integer linear programming model and propose an efficient dynamic programming (DP) algorithm for a 2-to-1 conveyor system. However, because the suggested DP cannot guarantee optimality in general settings, we propose two efficient genetic algorithms (GAs) to find near optimal solutions. Specifically, we design the reordering operation for making offspring to satisfy the precedence condition. We show that the proposed GAs perform prominently with respect to optimality gap and computation time; thus, they are amenable to environments where solutions must be obtained within tight time constraints. HighlightsWe investigate the paint batching problem on M-to-1 conveyor systems with the objective of minimizing setup costs.We develop a mixed integer linear programming model for paint batching problem on M-to-1 conveyor systems.We propose an efficient dynamic programming (DP) algorithm for a 2-to-1 conveyor system.We suggest efficient two genetic algorithms for general M-to-1 conveyor systems.These algorithms are prominent in terms of computation time and optimality gap.

In this study, we estimate air pollutants emission from agricultural waste burning. We investigated activities related to agricultural waste burning such as crop burning rates, location, and time by region.The average crop burning rates per square meter farmland of fruits, pulses, barleys, cereals, vegetables, and spe-cial crops were 273.1g/m 2 , 105.7g/m 2 , 7.4g/m 2 , 121.0g/m 2 , 290.7g/m 2 , and 392.9g/m , respectively. We estimated air pollutants emissions with pre-developed emission factors. The estimated air pollutant emission of agricultural biomass burning were CO 148,028 ton/year, NO x 5,220ton/year, SO x 11ton/year, VOC 59,767ton/year, TSP 21,548ton/year, PM 10 8,909ton/year, PM 2.5 7,405ton/year, and NH 3 5ton/year. When these results compared with the entire emissions of national inventory(CAPSS), CO, VOC, PM 10 account for about 17.8%, 6.2%, 6.7% of the total, respectively. Key words : Emission inventory, Biomass burning, Agricultural waste burning, Air pollutant emission

Background The common long-arm octopus (Octopus minor) is found in mudflats of subtidal zones and faces numerous environmental challenges. The ability to adapt its morphology and behavioral repertoire to diverse environmental conditions makes the species a promising model for understanding genomic adaptation and evolution in cephalopods. Findings The final genome assembly of O. minor is 5.09 Gb, with a contig N50 size of 197 kb and longest size of 3.027 Mb, from a total of 419 Gb raw reads generated using the Pacific Biosciences RS II platform. We identified 30,010 genes; 44.43% of the genome is composed of repeat elements. The genome-wide phylogenetic tree indicated the divergence time between O. minor and Octopus bimaculoides was estimated to be 43 million years ago based on single-copy orthologous genes. In total, 178 gene families are expanded in O. minor in the 14 bilaterian species. Conclusions We found that the O. minor genome was larger than that of closely related O. bimaculoides, and this difference could be explained by enlarged introns and recently diversified transposable elements. The high-quality O. minor genome assembly provides a valuable resource for understanding octopus genome evolution and the molecular basis of adaptations to mudflats.

Background Echiurida is one of the most intriguing major subgroups of annelida because, unlike most other annelids, echiurids lack metameric body segmentation as adults. For this reason, transcriptome analyses from various developmental stages of echiurid species can be of substantial value for understanding precise expression levels and the complex regulatory networks during early and larval development. Results A total of 914 million raw RNA-Seq reads were produced from 14 developmental stages of Urechis unicinctus and were de novo assembled into contigs spanning 63,928,225 bp with an N50 length of 2700 bp. The resulting comprehensive transcriptome database of the early developmental stages of U. unicinctus consists of 20,305 representative functional protein-coding transcripts. Approximately 66% of unigenes were assigned to superphylum-level taxa, including Lophotrochozoa (40%). The completeness of the transcriptome assembly was assessed using benchmarking universal single-copy orthologs; 75.7% of the single-copy orthologs were presented in our transcriptome database. We observed 3 distinct patterns of global transcriptome profiles from 14 developmental stages and identified 12,705 genes that showed dynamic regulation patterns during the differentiation and maturation of U. unicinctus cells. Conclusions We present the first large-scale developmental transcriptome dataset of U. unicinctus and provide a general overview of the dynamics of global gene expression changes during its early developmental stages. The analysis of time-course gene expression data is a first step toward understanding the complex developmental gene regulatory networks in U. unicinctus and will furnish a valuable resource for analyzing the functions of gene repertoires in various developmental phases.

Objective We evaluated the differences in brain morphology among patients with juvenile myoclonic epilepsy according to the occurrence of absence seizures. Materials and methods Twenty-one juvenile myoclonic epilepsy patients with (n = 6) and without (n = 15) absence seizures were enrolled. We analyzed whole-brain T1-weighted magnetic resonance imaging using FreeSurfer 5.1. Measures of cortical morphology, such as thickness, surface area, volume, and curvature, and the volumes of subcortical structures, the cerebellum, and cerebrum, were compared between the groups. Moreover, we quantified correlations between clinical variables and each measures of abnormal brain morphology. Results Compared to normal controls, patients without absence seizures demonstrated thinning of the cortical thickness in the right hemisphere, including the post-central, lingual, orbitofrontal, and lateral occipital cortex. Compared to normal controls, patients with absence seizures had more widespread thinning of the cortical thickness, including the right post-central, lingual, orbitofrontal, and lateral occipital cortexes as well as the right inferior temporal cortex. Additionally, the volume of cerebellar white matter in patients without absence seizures was significantly smaller than that in normal controls. Patients with absence seizures had a much smaller cerebellar white matter volume than normal controls or patients without absence seizures. Moreover, there was significantly positive correlation between the age of seizure onset and the volume of cerebellar white matter in patients with juvenile myoclonic epilepsy. Conclusions We demonstrated that there were significant brain morphology differences in patients with juvenile myoclonic epilepsy according to the presence of absence seizures. These findings support the hypothesis that juvenile myoclonic epilepsy may be a heterogeneous syndrome.

This study aimed to investigate the clinical and radiological findings in patients with transient global amnesia and to evaluate structural abnormalities using voxel-based morphometry. The subjects were diagnosed with transient global amnesia. For the voxel-based morphometry analyses, Statistical Parametric Mapping, running on the MATLAB platform (MathWorks, Natick, MA, USA), was employed to analyze the structural differences between patients with transient global amnesia and control subjects. Eighty patients met the inclusion criteria. Twenty-three patients (29%) were men, and 57 patients (71%) were women. There were significantly more women among the transient global amnesia patients compared with the general Korean population. MRI revealed hippocampal cavities in 41 patients (51%), and the incidence of such cavities was significantly different from that of the control subjects (24%). There were no differences in the clinical factors between the patients with and without hippocampal cavities. Diffusion-weighted imaging was performed in 54 patients, and 13 patients (24%) exhibited high signal intensity in the hippocampus. There were also no differences in the clinical factors between the patients with and without high signal intensities in the hippocampus on diffusion-weighted imaging. Twenty-six patients underwent three-dimensional volumetric T1-weighted imaging that produced results suitable for voxel-based morphometry, and these patients presented with gray matter volume reductions in the hippocampus, cingulum, and cerebellum. There were significant structural differences in the limbic structures between patients with transient global amnesia and the control subjects that might have contributed to vulnerability of the memory pathways of the patients with transient global amnesia.

We present an optimal test resource allocation strategy using uncertainty reduction in an environment where resource capacity changes dynamically according to engineering activity. The dynamics of test capacity change are modeled using a linear programming model and then extended and generalized to a Markov decision process. We analyze the model to develop structural results and illustrate its behavior with numerical examples. To the best of our knowledge, this model is the first to define, formalize, and analyze the decision-making process associated with reducing final test time in an environment where capacity may be dynamically increased, depending on engineering activity results.

Background: We evaluated the cortical morphology in patients with orthostatic intolerance. Methods: Thirty patients with orthostatic intolerance, as well as age- and sex-matched normal controls, were enrolled in this study. We divided the patients into orthostatic hypotension (n = 22) and postural tachycardia syndrome (n = 8) groups based on their response to a head-up tilt table test. We analyzed whole-brain T1-weighted MRI images using FreeSurfer 5.1. The measures of cortical morphology were compared between the groups. Results: The cortical thickness in the right hemisphere, including the medial orbitofrontal, peri-calcarine, post-central, inferior temporal, and lateral occipital cortex, and in the peri-calcarine cortex of the left hemisphere was thinned in patients with orthostatic hypotension compared to normal controls. The other measures of cortical morphology, including the surface area, volume, and curvatures, did not differ between patients with orthostatic hypotension and normal controls. However, none of the measures of cortical morphology differed between patients with postural tachycardia syndrome and normal controls. Conclusions: We demonstrated that the cortical morphology significantly changed in patients with orthostatic hypotension but not in patients with postural tachycardia syndrome compared to normal controls. These findings support the hypothesis that orthostatic intolerance is a heterogeneous syndrome.

BACKGROUND Tunnel misplacement is a common cause of failed anterior cruciate ligament (ACL) reconstruction. In this study, the accuracy of the femoral tunnel position was evaluated in robot-assisted ACL reconstruction using a magnetic resonance imaging (MRI)-based navigation system. We hypothesized that a difference of less than 2 mm between the planned femoral tunnel position and the created one was achievable. METHODS Four cadaveric knees underwent robot-assisted ACL reconstruction. A 3-dimensional model using pre-operative MRI images was used for preoperative planning, and a computed tomography (CT) scan was performed postoperatively. The planned and the created femoral tunnels were compared to assess the accuracy of the femoral tunnel position. RESULTS The distance between the intra-articular points of the planned and the created tunnels was 7.78 mm in the first experiment and 1.47 mm in the last one. The difference in tunnel length was 4.62 mm in the first experiment and 0.99 mm in the last one. CONCLUSIONS Accuracy of the femoral tunnel position improved with each robot-assisted ACL reconstruction using an MRI-based navigation system. In the last experiment, the accuracy of the femoral tunnel position was satisfactory.

// Doo-Sik Kong 1, 2, 3, * , Junhyung Kim 2, * , Gyuha Ryu 3, * , Hye-Jin You 2, 3 , Joon Kyung Sung 4 , Yong Hee Han 5 , Hye-Mi Shin 2, 3 , In-Hee Lee 2 , Sung-Tae Kim 6 , Chul-Kee Park 7 , Seung Hong Choi 8 , Jeong Won Choi 1 , Ho Jun Seol 1 , Jung-Il Lee 1 and Do-Hyun Nam 1, 2, 3 1 Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University, Seoul, Republic of Korea 2 Institute for Refractory Cancer Research, Samsung Medical Center, Seoul, Republic of Korea 3 Department of Health Science and Technology, Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Republic of Korea 4 Department of Computer Science, Korea University, Seoul, Republic of Korea 5 Medical System Research Department, Convergence Technology Institute, Hyundai Heavy Industries, Co., Ltd, Ulsan, Republic of Korea 6 Department of Radiology, Samsung Medical Center, Seoul, Republic of Korea 7 Department of Neurosurgery, Seoul National University Hospital, Seoul, Republic of Korea 8 Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea * These authors have contributed equally to this work Correspondence to: Do-Hyun Nam, email: nsnam@skku.edu Keywords: quantitative imaging; glioblastoma; radiomic; classification; phenotypes Received: January 31, 2017 Accepted: September 06, 2017 Published: January 05, 2018 ABSTRACT Quantitative imaging biomarkers have increasingly emerged in the field of research utilizing available imaging modalities. We aimed to identify good surrogate radiomic features that can represent genetic changes of tumors, thereby establishing noninvasive means for predicting treatment outcome. From May 2012 to June 2014, we retrospectively identified 65 patients with treatment-naive glioblastoma with available clinical information from the Samsung Medical Center data registry. Preoperative MR imaging data were obtained for all 65 patients with primary glioblastoma. A total of 82 imaging features including first-order statistics, volume, and size features, were semi-automatically extracted from structural and physiologic images such as apparent diffusion coefficient and perfusion images. Using commercially available software, NordicICE, we performed quantitative imaging analysis and collected the dataset composed of radiophenotypic parameters. Unsupervised clustering methods revealed that the radiophenotypic dataset was composed of three clusters. Each cluster represented a distinct molecular classification of glioblastoma; classical type, proneural and neural types, and mesenchymal type. These clusters also reflected differential clinical outcomes. We found that extracted imaging signatures does not represent copy number variation and somatic mutation. Quantitative radiomic features provide a potential evidence to predict molecular phenotype and treatment outcome. Radiomic profiles represents transcriptomic phenotypes more well.

Biomass burning is one of the significant emission source of PM and CO, but a few studies are reported in Korea. Air pollutants emission from biomass burning such as wood stove and boiler, and wood-pellet stove and boiler were estimated in this study. Activity levels related to biomass burning such as fuel types, amount of fuel loading, and location and temporal variation were investigated by field survey over Korea. Fuel loadings were 14.9 kg/day for wood stove, 31.3 kg/day for wood boiler, 12.8 kg/day for wood-pellet stove, 32.5 kg/day for wood-pellet boiler during the season of active use. These were mostly burned in winter season from october to april of next year. Estimated annual emissions from wood stove & boiler were CO 76,677, 710, 70, VOC 20,941, TSP 6,605, PM10 2,921, PM2.5 1,851, and NH3 7 ton/yr, respectively. Emissions from wood-pellet stove and boiler were CO 32,798, 1,830, 25, VOCs 5,673, TSP 629, PM10 457, PM2.5 344, and 2 ton/yr, respectively. When the emission estimates are compared with total emissions of the national emission inventory (CAPSS: Clean Air Policy Support System), Those occupy 12.5%, 2.8% of total national emission for CO and PM10, respectively. These results show wood and wood-pellet burning appliances were one of the major source of air pollution in Korea. In future, these types of heaters need to be regulated to reduce air pollution, especially in suburb area.

The problem of constrained sequencing of a set of jobs on a conveyor system with the objective of minimizing setup cost is investigated in this paper....

There have been various studies showing increased iron levels in parkinsonian disorders. The purpose of this study was to demonstrate topographical differences of brain iron deposition between progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple system atrophy (MSA-p) with SWI images.A total of 11 patients with PSP, 12 with MSA-p, 15 with Parkinson's disease (PD), and 20 age-matched healthy controls underwent SWI of the brain. Mean phase shift values of the red nucleus (RN), substantia nigra (SN), head of the caudate nucleus (CN), globus pallidus (GP), putamen (PUT), and thalamus (TH) were calculated and compared between groups. A voxel-based analysis of the processed SWI was performed to determine topographical differences of iron-related hypointense signals in PUT, GP, and TH.Patients with PSP and MSA-p had significantly higher levels of iron deposition than control and PD groups. Comparing patients with PSP and MSA-p, differences were found in iron concentrations of the RN, SN, GP, and TH, which were higher in the PSP group. However, iron levels in the PUT were higher in the MSA group (p0.05). The area under curve (AUC) indicated that the PUT was the most valuable nucleus in differentiating MSA-p from PSP and PD according to phase shift values (AUC=0.836). Meanwhile the GP (AUC=0.869) and TH (AUC=0.884) were the two most valuable nuclei in differentiating PSP from MSA-p and PD. Voxel-based analysis showed subregional differences in iron-related hypointense signals in the PUT, GP, and TH between MSA-p and PSP groups. Patients with MSA-p had significant increases of iron-related hypointense signals in the posterolateral PUT and adjacent lateral aspect of the GP, whereas the PSP group had increased hypodense signals in the anterior and medial aspects of the GP and TH.Our data demonstrate that pathological iron accumulations are more prevalent and severe in PSP compared to MSA-p. The distribution of high-iron-content regions in this study reflects pathoanatomically relevant sites. This finding allows for the use of MRI-based brain iron mapping as a technique to indirectly identify pathological changes.

Ischemic stroke is accompanied by structural deformation and functional deficits in the affected hemisphere. Within a couple of hours after symptom onset, the accurate identification of brain characteristics is critical to design the therapeutic strategies and it can potentially improve overall brain tissue viability by minimizing irreversible brain damage. In this study, white matter integrity and functional connectivity within 2-4h after right middle cerebral artery occlusion in rats were investigated using multimodal magnetic resonance imaging. During this stage, diffusion tensor image (DTI) revealed that fractional anisotropy along the ipsilesional external capsule was slightly increased as compared with preoperative baseline. Resting state functional MRI (rs-fMRI) showed that the inter-hemispheric functional connectivities from primary motor (M1), primary somatosensory of forelimb (S1FL), and barrel field (S1BF) seeds were considerably reduced at the hyperacute stage. Fractional amplitudes of low frequency fluctuations (fALFF) from rs-fMRI were significantly enhanced at the hyperacute stage in the frequency spectrum between 0.01 and 0.08Hz. In addition, the changes in fALFF were negatively correlated with the number of functionally connected voxels in M1, S1FL and S1BF. Our results suggest that these techniques are useful tools to evaluate remarkable brain changes in the hyperacute stage of ischemic stroke.

In this study we first explain details of the semiconductor manufacturing processes and cluster tools. Then we discuss the problems in current fab layout and cluster tool architecture. As a solution to these problems, we propose the ILE (In-Line EFEM) architecture in which wafer movements are conducted through interconnected EFEMs (Equipment Front End Modules) instead of AMHS (Automated Material Handling System). Then we model the pilot ILE system using discrete event simulation and analyze the cycle time. Finally we compare three different scenarios of equipment layout in the ILE system in terms of cycle time.

This paper discusses characteristics unique in the two-phase high-frequency-testing (HFT) environment in semiconductor manufacturing. We believe this paper is the first to define, formalize, and analyze the decision making problem associated with the two-phase HFT. Specifically, this paper defines the problem of minimizing the total HFT capacity usage by systematically finding the optimal number of preliminary HFT bin-1 chips subject to the main HFT, with the existence of the target service rate. We also propose a heuristic algorithm that exploits the special structure of the problem for efficiently obtaining a near-optimal solution. Finally, a numerical analysis and a case study have been conducted to gain more insights on the problem structure and the proposed algorithm.

Purpose: To evaluate the temporal and spatial resolution of magnetic resonance (MR) temperature imaging when using the proton resonance frequency (PRF) method combined with the keyhole technique. Materials and Methods: Tissue-mimicking phantom and swine muscle tissue were microwave-heated by a coaxial slot antenna. For the sake of MR hardware safety, MR images were sequentially acquired after heating the subjects using a spoiled gradient (SPGR) pulse sequence. Reference raw (k-space) data were collected before heating the subjects. Keyhole temperature images were reconstructed from full k-space data synthesized by combining the peripheral phase-encoding part of the reference raw data and the center phase-encoding keyhole part of the time sequential raw data. Each keyhole image was analyzed with thermal error, and the signal-to-noise ratio (SNR) was compared with the self-reference (nonkeyhole) images according to the number of keyhole phase-encoding (keyhole-data size) portions. Results: In applied keyhole temperature images, smaller keyhole-data sizes led to more temperature error increases, but the SNR did not decreased comparably. Additionally, keyhole images with a keyhole-data size of