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USP15 regulates dynamic protein-protein interactions of the spliceosome through deubiquitination of PRP31.
Post-translational modifications contribute to the spliceosome dynamics by facilitating the physical rearrangements of the spliceosome. Here, we report USP15, a deubiquitinating enzyme, as a regulator of protein-protein interactions for the spliceosome dynamics. We show that PRP31, a component of U4 snRNP, is modified with K63-linked ubiquitin chains by the PRP19 complex and deubiquitinated by USP15 and its substrate targeting factor SART3. USP15SART3 makes a complex with USP4 and this ternary complex serves as a platform to deubiquitinate PRP31 and PRP3. The ubiquitination and deubiquitination status of PRP31 regulates its interaction with the U5 snRNP component PRP8, which is required for the efficient splicing of chromosome segregation related genes, probably by stabilizing the U4/U6.U5 tri-snRNP complex. Collectively, our data suggest that USP15 plays a key role in the regulation of dynamic protein-protein interactions of the spliceosome
DC-DFT for Open Shells: How to Deal with Spin Contamination
Density functional theory (DFT) is widely used to predict chemical
properties, but its accuracy is limited by functional approximations and their
approximate self-consistent densities. Density-corrected DFT (DC-DFT) is the
study of the errors due to densities and Hartree-Fock DFT (HF-DFT) uses HF
densities to improve energetics. With increasing use of HF-DFT, the question of
how to address strong spin contamination in the HF calculation becomes
increasingly important. We compare two different open-shell HF densities across
13 different DFT functionals and two DC-DFT methods. For significant spin
contamination, ROHF densities outperform UHF densities by as much as a factor
of 3, depending on the energy functional, and ROHF-DFT improves over
self-consistent DFT for most of the tested functionals. We refine the
DC(HF)-DFT algorithm, recommending ROHF-DFT in cases of severe spin
contamination.Comment: 10 pages, 4 figures, 2 table
The effects of functional instability of the ankle joint on balance
BACKGROUND: Individuals who suffer from ankle instability may experience restricted movement and a weakening of the
muscles that support the ankle.
PURPOSE: The aim of this study was to investigate the effects of functional instability of the ankle joint on static and dynamic
balance performances.
METHODS: Twenty-five participants (8 male, 17 female) were recruited for this study. The subjects were divided into two
groups: an ankle instability and a normal ankle stability group. The static and dynamic limits of stability performance were
assessed in single leg standing using the BioRescue device. In addition, the Functional Reach Test (FRT) and the Modified
Functional Reach Test (MFRT) were also recorded.
RESULTS: Significant differences between the two groups were found in the moving distance and the mean velocity of the
center of pressure during the single leg standing test, the pendular limits of stability test, and the MFRT. However, the FRTshowed no significant difference between the two groups. The results showed that the static and dynamic balance performances were reduced in the ankle instability group compared with the control group.
CONCLUSION: Both the MFRT and BioRescue were sensitive and appropriate to identify clinically important differences
between the two groups. The MFRT is a quick and inexpensive clinical measure of postural instability relevant to individuals
with ankle instability. Further studies should use the MFRT to determine the effectiveness of clinical interventions for ankle
instability that target improvements in balance
Development of Formation Flying CubeSats and Operation Systems for the CANYVAL-C Mission: Launch and Lessons Learned
The CubeSat Astronomy NASA and Yonsei using Virtual telescope ALignment for Coronagraph (CANYVAL-C) is a technology demonstration mission that shows the concept of a virtual space telescope using two CubeSats in formation flying. The final goal of the mission is to obtain several images of the solar corona during an artificial solar eclipse created by the two CubeSats, Timon (1U CubeSat) and Pumbaa (2U CubeSat). To implement this mission, two CubeSats in formation flying and a ground segment have been developed. The CubeSats were constructed mainly with commercial off the shelf components, sharing the bus architecture. The payload of each CubeSat is a visible camera and an occulter to block the light from the photosphere of the Sun. The occulter is composed of tape measures and a black-colored polyimide film; the system size is smaller than 0.5U (10 × 10 × 5 cm3) while it stowed and enlarged to 0.75 × 0.75 m2 after spreading the film. The 3D-printed propulsion system is smaller than 0.5U and facilitates accurate positioning maneuvers of Pumbaa. The on-board computer has multi-task processing capabilities and a space-saving configuration which is integrated with the GNSS receiver and the UHF transceiver. The core technology for the mission implementation is the precise formation flying guidance, navigation, and control system with a cold-gas propulsion system and an inter-satellite link system. The specification of each CubeSat system was evaluated using numerical simulations and ground testing. To operate CubeSats, the ground segment was constructed with some components, including the UHF ground station (UGS), flight dynamics system (FDS), mission analysis and planning system (MAPS), and spacecraft operation system (SOS). Each component works under the environment of an integrated graphic user interface. In particular, the UGS handles the RF communication, data storage, and instrument control for tracking CubeSats. The FDS processes the navigation data to precisely estimate absolute position and velocity. Then, the MAPS determines the allowable mission schedule and parameter set for implementing maneuvers of each CubeSat. Using the MAPS, feasibility of the mission operation canbe ensured through numerical simulations based on the solutions from the FDS. Finally, the SOS is the interface system between each component, processing telemetry and generating telecommand. The CubeSats were launched on March 22, 2021, by Soyuz-2.1a with a Fregat stage
Assessing Environmentally Sensitive Land to Desertification Using MEDALUS Method in Mongolia
Desertification is a global phenomenon caused by various processes, including climate change, vegetation processes, and human activities. The need to combat desertification is increasing in many countries. A reasonable assessment of the vulnerability or sensitivity of land cover to desertification at national scales is crucial to formulate appropriate strategies or policies for combating it. The main purpose of this work was to quantitatively assess the sensitivity of land cover to desertification in Mongolia using the MEDALUS approach. The MEDALUS method is a widely known technique for assessing desertification in the Mediterranean area. In this study, the method was adjusted to be applied to Mongolia, while the numerical methods of the MEDALUS remained the same. The modified MEDALUS method used nine factors from 2003 and 2008 to quantify the sensitivity of land to desertification. As a result, our study resulted in the calculation and spatial distribution of the Environmental Sensitive Area Index (ESAI), produced throughout Mongolia. In 2003, the middle region of the southern Mongolia had the highest sensitivity to desertification, while sensitivity in 2008 increased in the western area. Mongolia’s area with the highest ESAI range increased approximately five times, indicating rapid desertification occurring throughout Mongolia from 2003 to 2008
Engineered biosynthesis of milbemycins in the avermectin high-producing strain Streptomyces avermitilis
Additional file 3 : Figure S2. HPLC analysis of milbemycins produced from S. avermitilis mutant strains and authentic standard milbemycins
The impact of comorbid anxiety on quantitative EEG heterogeneity in children with attention-deficit/hyperactivity disorder
ObjectiveThe objective of this study was to compare quantitative electroencephalography (Q-EEG) characteristics of children with Attention-deficit/hyperactivity disorder (ADHD), taking into account the presence of a comorbidity for anxiety disorder. It also sought to investigate the impact of comorbid anxiety on the Q-EEG heterogeneity of children with ADHD.MethodA total of 141 children with ADHD but without comorbid anxiety (ADHD-Only), 25 children with a comorbidity for anxiety disorder (ADHD-ANX) and 43 children in the control group were assessed. To compare Q-EEG characteristics between groups, we performed ANCOVA (Analysis of Covariance) on relative power and theta/beta ratio (TBR) controlling for covariates such as age, sex, and FSIQ. Relative power values from 19 electrodes were averaged for three regions (frontal, central and posterior). Furthermore, cluster analysis (Ward’s method) using the squared Euclidian distance was conducted on participants with ADHD to explore the impact of anxiety on the heterogeneity of Q-EEG characteristics in ADHD.ResultsThere were no significant group differences in cognitive and behavioral measures. However, significant differences between groups were observed in the theta values in the central region, and the beta values in the frontal, central and posterior regions. In post hoc analyses, It was found that the ADHD-ANX group has significantly higher beta power values than the ADHD-Only group in all regions. For the theta/beta ratio, the ADHD-Only group had significantly higher values than the ADHD-ANX group in frontal, central and posterior regions. However, the control group did not show significant differences compared to both the ADHD-Only and ADHD-ANX group. Through clustering analysis, the participants in the ADHD-Only and ADHD-ANX groups were classified into four clusters. The ratios of children with comorbidities for anxiety disorder within each cluster were significantly different (χ2 = 10.018, p = 0.019).ConclusionAttention-deficit/hyperactivity disorder children with comorbid anxiety disorder showed lower theta power in the central region, higher beta power in all regions and lower TBR in all regions compared to those without comorbid anxiety disorder. The ratios of children with comorbidities for anxiety disorder within each cluster were significantly different
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