Stability of Wake-Sleep Cycles Requires Robust Degradation of the PERIOD Protein

D’Alessandro, Matthew,Beesley, Stephen,Kim, Jae Kyoung,Jones, Zachary,Chen, Rongmin,Wi, Julie,Kyle, Kathleen,Vera, Daniel,Pagano, Michele,Nowakowski, Richard,Lee, Choogon Elsevier 2017 Current Biology Vol.27 No.22

<P><B>Summary</B></P> <P>Robustness in biology is the stability of phenotype under diverse genetic and/or environmental perturbations. The circadian clock has remarkable stability of period and phase that—unlike other biological oscillators—is maintained over a wide range of conditions. Here, we show that the high fidelity of the circadian system stems from robust degradation of the clock protein PERIOD. We show that PERIOD degradation is regulated by a balance between ubiquitination and deubiquitination, and that disruption of this balance can destabilize the clock. In mice with a loss-of-function mutation of the E3 ligase gene <I>β-Trcp2</I>, the balance of PERIOD degradation is perturbed and the clock becomes dramatically unstable, presenting a unique behavioral phenotype unlike other circadian mutant animal models. We believe that our data provide a molecular explanation for how circadian phases, such as wake-sleep onset times, can become unstable in humans, and we present a unique mouse model to study human circadian disorders with unstable circadian rhythm phases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nonlinear degradation of PER is required for the robustness of circadian rhythms </LI> <LI> PER degradation is regulated by a balance between ubiquitination and deubiquitination </LI> <LI> Disrupting this balance causes irregular wake-sleep cycles in mice </LI> </UL> </P>

Complete nucleotide sequence of Dendrocalamus latiflorus and Bambusa oldhamii chloroplast genomes.

Wu, F-H,Kan, D-P,Lee, S-B,Daniell, H,Lee, Y-W,Lin, C-C,Lin, N-S,Lin, C-S Heron Pub 2009 Tree physiology Vol.29 No.6

<P>Although bamboo is one of the most important woody crops in Asia, information on its genome is still very limited. To investigate the relationship among Poaceae members and to understand the mechanism of albino mutant generation in vitro, the complete chloroplast genome of two economically important bamboo species, Dendrocalamus latiflorus Munro and Bambusa oldhamii Munro, was determined employing a strategy that involved polymerase chain reaction (PCR) amplification using 443 novel primers designed to amplify the chloroplast genome of these two species. The lengths of the B. oldhamii and D. latiflorus chloroplast genomes are 139,350 and 139,365 bp, respectively. The organization structure and the gene order of these two bamboos are identical to other members of Poaceae. Highly conserved chloroplast genomes of Poaceae facilitated sequencing by the PCR method. Phylogenetic analysis using both chloroplast genomes confirmed the results obtained from studies on chromosome number and reproductive organ morphology. There are 23 gaps, insertions/deletions > 100 bp, in the chloroplast genomes of 10 genera of Poaceae compared in this study. The phylogenetic distribution of these gaps corresponds to their taxonomic placement. The sequences of these two chloroplast genomes provide useful information for studying bamboo evolution, ecology and biotechnology.</P>

ETRI-모아레 스캐너를 이용한 3차원 모델의 자동생성

권대현(Daniel D. Kwon),최이배(Yi-Bae Choi),이의택(Ee-Teak Lee) 한국방송·미디어공학회 1999 한국방송공학회 학술발표대회 논문집 Vol.1999 No.-

Intermediate-term outcomes after robotic ureteral reconstruction for long-segment (≥4 centimeters) strictures in the proximal ureter: A multi-institutional experience

Matthew Lee,Ziho Lee,Helaine Koster,Minsuk Jun,Aeen M. Asghar,Randall Lee,David Strauss,Neel Patel,Daniel Kim,Sreeya Komaravolu,Alice Drain,Michael J. Metro,Lee Zhao,Michael Stifelman,Daniel D. Eun 대한비뇨의학회 2021 Investigative and Clinical Urology Vol.62 No.1

Purpose: To report our intermediate-term, multi-institutional experience after robotic ureteral reconstruction for the management of long-segment proximal ureteral strictures. Materials and Methods: We retrospectively reviewed our Collaborative of Reconstructive Robotic Ureteral Surgery (CORRUS) database to identify all patients who underwent robotic ureteral reconstruction for long-segment (≥4 centimeters) proximal ureteral strictures between August 2012 and June 2019. The primary surgeon determined the specific technique to reconstruct the ureter at time of surgery based on the patient's clinical history and intraoperative findings. Our primary outcome was surgical success, which we defined as the absence of ureteral obstruction on radiographic imaging and absence of obstructive flank pain. Results: Of 20 total patients, 4 (20.0%) underwent robotic ureteroureterostomy (RUU) with downward nephropexy (DN), 2 (10.0%) underwent robotic ureterocalycostomy (RUC) with DN, and 14 (70.0%) underwent robotic ureteroplasty with buccal mucosa graft (RU-BMG). Median stricture length was 4 centimeters (interquartile range [IQR], 4–4; maximum, 5), 6 centimeters (IQR, 5–7; maximum, 8), and 5 centimeters (IQR, 4–5; maximum, 8) for patients undergoing RUU with DN, RUC with DN, and RU-BMG, respectively. At a median follow-up of 24 (IQR, 14–51) months, 17/20 (85.0%) cases were surgically successful. Two of four patients (50.0%) who underwent RUU with DN developed stricture recurrences within 3 months. Conclusions: Long-segment proximal ureteral strictures may be safely and effectively managed with RUC with DN and RU-BMG. Although RUU with DN can be utilized, this technique may be associated with a higher failure rate.

Stock Timing by Analysts

Naveen D. Daniel,Sangmook Lee,Lalitha Naveen 한국재무학회 2016 한국재무학회 학술대회 Vol.2016 No.05

Prior literature has documented that analysts engage in valuable information discovery and information interpretation. Our contribution is to introduce and document a third role that analysts play that is also valuable to investors, which we term “stock timing.” Specifically, we define a timing report as one where the analyst revises his recommendation but does not revise the Price Target or any of the 23 fundamental drivers of stock price (such as EPS, FCF) tracked by I/B/E/S. Because the analyst maintains the same price target as in his prior report but still revises his recommendation, such timing calls are contrarian valuation calls. Analysts issue timing downgrades (upgrades) in response to price increases (declines) since the release of their prior report on the firm. About 30% of all revisions are timing reports, indicating the importance of the timing role played by analysts. We find the return over a 3-day window around the report date is over 2% in magnitude. Further, 62% of the reports are winners (have announcement returns that have the correct sign), 10% of the reports are large enough to be considered influential, and 37% of the reports are persistent winners. These results suggest that analysts have timing ability. We find considerable cross-sectional and time-series variation in timing ability. We find that the probability of issuing a timing report is positively related to the opportunities to time the stock provided by potential mispricing. Conditional on issuing a timing report, the probability of issuing a winner, an influential winner, or a persistent winner is positively related to analyst experience and negatively related to the costs associated with issuing a timing report.

IGRINS Mirror Mount Design for Three Off-Axis Collimators and One Slit-Viewer Fold Mirror

Rukdee, Surangkhana,Park, Chan,Kim, Kang-Min,Lee, Sung-Ho,Chun, Moo-Young,Yuk, In-Soo,Oh, Hee-Young,Jung, Hwa-Kyoung,Lee, Chung-Uk,Lee, Han-Shin,Rafal, Marc D.,Barnes, Stuart,Jaffe, Daniel T. 한국우주과학회 2012 Journal of Astronomy and Space Sciences Vol.29 No.2

The Korea Astronomy and Space Science Institute and the Department of Astronomy at the University of Texas at Austin are developing a near infrared wide-band high resolution spectrograph, immersion grating infrared spectrometer (IGRINS). The compact white-pupil design of the instrument optics uses seven cryogenic mirrors, including three aspherical off-axis collimators and four flat fold mirrors. In this study, we introduce the optomechanical mount designs of three off-axis collimating mirrors and one flat slit-viewer fold mirror. Two of the off-axis collimators are serving as H and K-band pupil transfer mirrors, and are designed as system alignment compensators in combination with the H2RG focal plane array detectors in each channel. For this reason, the mount designs include tip-tilt and parallel translation adjustment mechanisms to properly perform the precision alignment function. This means that the off-axis mirrors’ optomechanical mount designs are among the most sensitive tasks in all IGRINS system hardware. The other flat fold mirror is designed within its very limitedly allowed work space. This slit-viewer fold mirror is mounted with its own version of the six-point kinematic optics mount. The design work consists of a computer-aided 3D modeling and finite element analysis (FEA) technique to optimize the structural stability and the thermal behavior of the mount models. From the structural and thermal FEA studies, we conclude that the four IGRINS mirror mounts are well designed to meet all optical stability tolerances and system thermal requirements.

Genetic risk factors for rheumatoid arthritis differ in caucasian and Korean populations

Lee, Hye-Soon,Korman, Benjamin D.,Le, Julie M.,Kastner, Daniel L.,Remmers, Elaine F.,Gregersen, Peter K.,Bae, Sang-Cheol Wiley Subscription Services, Inc., A Wiley Company 2009 Vol.60 No.2

<B>Objective</B><P>Recent studies have identified a number of novel rheumatoid arthritis (RA) susceptibility loci in Caucasian populations. The aim of this study was to determine whether the genetic variants at 4q27, 6q23, CCL21, TRAF1/C5, and CD40 identified in Caucasians are also associated with RA in a Korean case–control collection. We also comprehensively evaluated the genetic variation within PTPN22, a well-established autoimmune disease–associated gene.</P><B>Methods</B><P>We designed an experiment to thoroughly evaluate the PTPN22 linkage disequilibrium region, using tag single-nucleotide polymorphisms (SNPs) and disease-associated SNPs at 5 RA-associated loci recently identified in Caucasians, in 1,128 Korean patients with RA and 1,022 ethnically matched control subjects. We also resequenced the PTPN22 gene to seek novel coding variants that might be contributing to disease in this population.</P><B>Results</B><P>None of the susceptibility loci identified in Caucasian patients with RA contributed significantly to disease in Koreans. Although tag SNPs covering the PTPN22 linkage disequilibrium block were polymorphic, they did not reveal any disease association, and resequencing did not identify any new common coding region variants in this population. The 6q23 and 4q27 SNPs assayed were nonpolymorphic in this population, and the TRAF1/C5, CD40, and CCL21 SNPs did not show any evidence for association with RA in this population of Korean patients.</P><B>Conclusion</B><P>The genetic risk factors for RA are different in Caucasian and Korean patients. Although patients of different ethnic groups share the HLA region as a major genetic risk locus, most other genes shown to be significantly associated with disease in Caucasians appear not to play a role in Korean patients with RA.</P>

Conjugated Polyelectrolytes as Efficient Hole Transport Layers in Perovskite Light-Emitting Diodes

Lee, Bo Ram,Yu, Jae Choul,Park, Jong Hyun,Lee, Seungjin,Mai, Cheng-Kang,Zhao, Baodan,Wong, Matthew S.,Jung, Eui Dae,Nam, Yun Seok,Park, Song Yi,Di Nuzzo, Daniele,Kim, Jin Young,Stranks, Samuel D.,Baza American Chemical Society 2018 ACS NANO Vol.12 No.6

<P>Perovskite-based optoelectronic devices have been rapidly developing in the past 5 years. Since the first report, the external quantum efficiency (EQE) of perovskite light-emitting diodes (PeLEDs) has increased rapidly through the control of morphology and structure from 0.1% to more than 11%. Here, we report the use of various conjugated polyelectrolytes (CPEs) as the hole injection layer in PeLEDs. In particular, we find that poly[2,6-(4,4-bis-potassium butanylsulfonate)-4<I>H</I>-cyclopenta-[2,1-<I>b</I>;3,4-<I>b</I>′]-dithiophene)] (PCPDT-K) transfers holes effectively, blocks electron transport from the perovskite to the underlying ITO layer, and reduces luminescence quenching at the perovskite/PCPDT-K interface. Our optimized PeLEDs with PCPDT-K show enhanced EQE by a factor of approximately 4 compared to control PeLEDs with PEDOT:PSS, reaching EQE values of 5.66%, and exhibit improved device stability.</P> [FIG OMISSION]</BR>

Polymer Brushes via Controlled, Surface-Initiated Atom Transfer Radical Polymerization (ATRP) from Graphene Oxide

Lee, Sun Hwa,Dreyer, Daniel R.,An, Jinho,Velamakanni, Aruna,Piner, Richard D.,Park, Sungjin,Zhu, Yanwu,Kim, Sang Ouk,Bielawski, Christopher W.,Ruoff, Rodney S. WILEY-VCH Verlag 2010 Macromolecular Rapid Communications Vol.31 No.3

<P>A method for growing polymers directly from the surface of graphene oxide is demonstrated. The technique involves the covalent attachment of an initiator followed by the polymerization of styrene, methyl methacrylate, or butyl acrylate using atom transfer radical polymerization (ATRP). The resulting materials were characterized using a range of techniques and were found to significantly improve the solubility properties of graphene oxide. The surface-grown polymers were saponified from the surface and also characterized. Based on these results, the ATRP reactions were determined to proceed in a controlled manner and were found to leave the structure of the graphene oxide largely intact.</P><P> <img src='wiley_img/10221336-2010-31-3-MARC200900641-gra001.gif' alt='wiley_img/10221336-2010-31-3-MARC200900641-gra001'> </P> <B>Graphic Abstract</B> <P>The covalent attachment of ATRP initiators to graphene oxide followed by a surface-initiated polymerization affords derivatives with surface-attached polymer brushes. The product is found to have dramatically increased solubility without altering the structural properties inherent to graphene oxide. <img src='wiley_img/10221336-2010-31-3-MARC200900641-content.gif' alt='wiley_img/10221336-2010-31-3-MARC200900641-content'> </P>

Ultrastretchable Analog/Digital Signal Transmission Line with Carbon Nanotube Sheets

Lee, Yourack,Joo, Min-Kyu,Le, Viet Thong,Ovalle-Robles, Raquel,Lepró,, Xavier,Lima, Má,rcio D.,Suh, Daniel G.,Yu, Han Young,Lee, Young Hee,Suh, Dongseok American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.31

<P>Stretchable conductors can be used in various applications depending on their own characteristics. Here, we demonstrate simple and robust elastomeric conductors that are optimized for stretchable electrical signal transmission line. They can withstand strains up to 600% without any substantial change in their resistance (<= 10% as is and <= 1% with passivation), and exhibit suppressed charge fluctuations in the medium. The inherent elasticity of a polymeric rubber and the high conductivity of flexible, highly oriented carbon nanotube sheets were combined synergistically, without losing both properties. The nanoscopic strong adhesion between aligned carbon nanotube arrays and strained elastomeric polymers induces conductive wavy folds with microscopic bending of radii on the scale of a few micrometers. Such features enable practical applications such as in elastomeric length-changeable electrical digital and analog signal transmission lines at above MHz frequencies. In addition to reporting basic direct current, alternating current, and noise characterizations of the elastomeric conductors, various examples as a stretchable signal transmission line up to 600% strains are presented by confirming the capability of transmitting audio and video signals, as well as low-frequency medical signals without information distortion.</P>