Replication protein A (RPA) is a heterotrimeric complex and the major single-strand DNA (ssDNA) binding protein in eukaryotes. It plays important roles in DNA replication, repair, recombination, ...telomere maintenance, and checkpoint signaling. Because RPA is essential for cell survival, understanding its checkpoint signaling function in cells has been challenging. Several RPA mutants have been reported previously in fission yeast. None of them, however, has a defined checkpoint defect. A separation-of-function mutant of RPA, if identified, would provide significant insights into the checkpoint initiation mechanisms. We have explored this possibility and carried out an extensive genetic screen for Rpa1/Ssb1, the large subunit of RPA in fission yeast, looking for mutants with defects in checkpoint signaling. This screen has identified twenty-five primary mutants that are sensitive to genotoxins. Among these mutants, two have been confirmed partially defective in checkpoint signaling primarily at the replication fork, not the DNA damage site. The remaining mutants are likely defective in other functions such as DNA repair or telomere maintenance. Our screened mutants, therefore, provide a valuable tool for future dissection of the multiple functions of RPA in fission yeast.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface ...of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
We report on high angular resolution polarimetric observations of the nearby radio galaxy M87 using the Very Long Baseline Array at 24 GHz (
λ
= 1.3 cm) and 43 GHz (
λ
= 7 mm) in 2017–2018. New ...images of the linear polarization substructure in the nuclear region are presented, characterized by a two-component pattern of polarized intensity and smooth rotation of the polarization plane around the 43 GHz core. From a comparison with an analogous dataset from 2007, we find that this global polarization pattern remains stable on a time interval of 11 yr, while showing smaller month-scale variability. We discuss the possible Faraday rotation toward the M87 nucleus at centimeter to millimeter wavelengths. These results can be interpreted in a scenario where the observed polarimetric pattern is associated with the magnetic structure in the confining magnetohydrodynamic wind, which also serves as the source of the observed Faraday rotation.
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FMFMET, NUK, UL, UM, UPUK
We present a study of the sub-parsec scale radio structure of the radio galaxy 3C 84/NGC 1275 based on the Very Long Baseline Array data at 43 GHz. We discover a limb brightening in the "restarted" ...jet that is associated with the 2005 radio outburst. In the 1990s, the jet structure was ridge brightening rather than limb brightening, despite the observations being done with similar angular resolutions. This indicates that the transverse jet structure has recently changed. This change in the morphology reveals an interesting agreement with the gamma -ray flux increase, i.e., the gamma -ray flux in the 1990s was at least seven times lower than the current one. One plausible explanation for the limb brightening is that the velocity structure of the jet is in the context of the stratified jet, which is a successful scenario that explains the gamma -ray emission in some active galactic nuclei. If this is the case, then the change in apparent transverse structure might be caused by the change in the transverse velocity structure. We argue that the transition from ridge brightening to limb brightening is related to the gamma -ray time variability on the timescale of decades. We also discuss the collimation profile of the jet.
ABSTRACT
Class II CH3OH masers are used as a convenient tracer of disc-like structures in high-mass star formation. However, more than half of them show a complex distribution in Very Long Baseline ...Interferometry (VLBI) maps. The origin of such a complex distribution is still unknown. We conducted VLBI monitoring observations to unveil the origin of a complex class II CH3OH maser in the high-mass star-forming region G59.783+0.065. We observed the CH3OH maser at 6.7 GHz and the H2O maser at 22 GHz to probe detailed circumstellar kinematics and structures by the Japanese VLBI network and the VLBI Exploration of Radio Astrometry. We found similar bipolar distributions in both masers, specifically two clusters located 2000 au apart along the east–west direction. We detected a linear distribution of CH3OH masers in the western cluster. A position–velocity diagram shows that the western CH3OH masers trace a rotating disc-wind or infalling component inside an edge-on disc-like structure. In contrast to the simple bipolar expanding motions of the H2O masers, the CH3OH masers exhibited complex motions despite their spatial coincidence. Some of the eastern CH3OH masers showed bipolar expansions similar to the H2O masers, while others displayed random or even inward motions. Such complex kinematics and their close association with the H2O maser could occur at the boundary between outflow and inflow. We suggest that the complex distribution of class II CH3OH masers, like G59.783+0.065 arises from several distinct circumstellar structures that simultaneously achieve maser excitation.
Acute disseminated encephalomyelitis (ADEM) is a rare and immune-mediated inflammatory disorder of the central nervous system (CNS) that can be triggered by infections and vaccinations. To date, only ...anecdotal case studies have reported the association between ADEM incidence and seasonal
influenza vaccines, and multiple studies have found no association. This study aimed to investigate the association between the incidence of ADEM and seasonal influenza vaccines in a real-world setting using data from the United States Vaccine Adverse Event Reporting System (VAERS). Further,
propensity score matching and disproportionality analysis was performed by calculating the adjusted reporting odds ratio (ROR) of reported ADEM cases associated with seasonal influenza vaccines using multiple logistic regression. Additionally, we analysed the time-to-onset using Weibull shape
parameters (WSPs). The VAERS database contained 390,352 adverse events reported from January 2011 to December 2020. The ROR of seasonal influenza vaccines for ADEM was 3.02 (95% confidence interval: 1.72-5.33). The median duration (interquartile range) of ADEM was 11.0 (5.0-33.0)
days. The median duration of ADEM induced by egg culture-based influenza vaccine (Egg-based vaccine) and cell culture-based influenza vaccine (Cell-based vaccine) was 10.0 (5.0-24.0) and 91.0 (79.0-125.0) days (P < 0.001), respectively. Only Cell-based cases had WSP β
> 1, indicating a wear-out failure type. The incidence of ADEM within 30 days after administration of egg- and Cell-based vaccines was 78.6% and 0.0%, respectively. Our findings indicate that ADEM incidence is associated with seasonal influenza vaccines; thus, careful monitoring of ADEM
is required within the first month of Egg-based vaccination and after two months of Cell-based vaccination. Neurologists and general practitioners should exercise caution, as the timing for careful monitoring varies depending on the vaccine type.
Psoriasis can be a socially isolating disease due to debilitating physical symptoms and the stigma patients feel because of the appearance of their skin. Mental health comorbidities such as anxiety, ...depression and suicidal ideation and behaviour (SIB) are prevalent in patients with psoriasis. Patients with mild psoriasis can experience psychiatric comorbidities; however, disorders such as depression and SIB are more common in patients with severe psoriasis or psoriatic arthritis. Psychiatric disorders can both result from and contribute to progression of psoriasis, suggesting that psoriasis and psychiatric conditions, such as depression, may have overlapping biological mechanisms. Proinflammatory cytokines such as interleukin (IL)‐1 and IL‐6 are elevated in both psoriasis and depression, indicating that the inflammatory process may be involved in the progression of both diseases. Elevated cytokine levels in the central nervous system cause physiologic and biochemical changes that may contribute to the development of depression. In this review of the literature, we discuss the evidence that supports the association of psoriasis with mental health disorders and the tools used to detect the presence of these comorbidities. Additionally, we review the most prominent hypotheses on the mechanisms by which the inflammatory response and elevated cytokines can cause depression. These results highlight the role that systemic inflammation plays in the various mental health comorbidities associated with psoriasis, including depression and SIB.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Among vertebrates, fishes show an exceptional range of reproductive strategies regarding the expression of their sexuality. Fish sexualities were categorized into gonochorism, synchronous/sequential ...hermaphrodite, or unisexual reproduction. In gonochoristic fishes, sex is determined genetically or by environmental factors. After sex determination, the gonads are differentiated into ovary or testis, with the sex remaining fixed for the entire life cycle. In contrast, some sequential hermaphrodite fishes can change their sex from male to female (protandrous), female to male (protogynous), or serially (bi-directional sex change) in their life cycle. In many cases, sex change is cued by social factors such as the disappearance of a male or female from a group. This unique diversity in fishes provides an ideal animal model to investigate sex determination and differentiation in vertebrates. This review first discusses genetic-orientated sex determination mechanisms. Then, we address the gonadal sex differentiation process in a gonochoristic fish, using an example of the Nile tilapia. Finally, we discuss various types of sex change that occur in hermaphrodite fishes.
Abstract
At the Earth's magnetopause, the Kelvin‐Helmholtz (KH) instability, driven by the persistent velocity shear between the magnetosheath and the magnetosphere, has been frequently observed ...during northward interplanetary magnetic field periods and considered as one of the most important candidates for transporting and mixing plasmas across the magnetopause. However, how this process interacts with magnetic field fluctuations, which persistently exist near the magnetopause, has been less discussed. Here we perform a series of 2‐D fully kinetic simulations of the KH instability at the magnetopause considering a power law spectrum of initial fluctuations in the magnetic field. The simulations demonstrate that when the amplitude level of the initial fluctuations is sufficiently large, the KH instability evolves faster, leading to a more efficient plasma mixing within the vortex layer. In addition, when the spectral index of the initial fluctuations is sufficiently small, the modes whose wavelength is longer than the theoretical fastest growing mode grow dominantly. The fluctuating magnetic field also results in the formation of the well‐matured turbulent spectrum with a −5/3 index within the vortex layer even in the early nonlinear growth phase of the KH instability. The obtained spectral features in the simulations are in reasonable agreement with the features in KH waves events at the magnetopause observed by the Magnetospheric Multiscale mission and conjunctively by the Geotail and Cluster spacecraft. These results indicate that the magnetic field fluctuations may really contribute to enhancing the wave activities especially for longer wavelength modes and the associated mixing at the magnetopause.
Key Points
The 2‐D fully kinetic simulations of magnetopause Kelvin‐Helmholtz instability initially imposing power law field fluctuations are performed
The growth of the instability especially for long wavelength modes is enhanced by the fluctuating field, leading to more efficient mixing
Spectral features obtained from the simulations are in reasonable agreement with past spacecraft observations at the Earth's magnetopause
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We investigate the accuracy with which the reconnection electric field EM can be determined from in situ plasma data. We study the magnetotail electron diffusion region observed by National ...Aeronautics and Space Administration's Magnetospheric Multiscale (MMS) on 11 July 2017 at 22:34 UT and focus on the very large errors in EM that result from errors in an LMN boundary normal coordinate system. We determine several LMN coordinates for this MMS event using several different methods. We use these M axes to estimate EM. We find some consensus that the reconnection rate was roughly EM = 3.2 ± 0.6 mV/m, which corresponds to a normalized reconnection rate of 0.18 ± 0.035. Minimum variance analysis of the electron velocity (MVA‐ve), MVA of E, minimization of Faraday residue, and an adjusted version of the maximum directional derivative of the magnetic field (MDD‐B) technique all produce reasonably similar coordinate axes. We use virtual MMS data from a particle‐in‐cell simulation of this event to estimate the errors in the coordinate axes and reconnection rate associated with MVA‐ve and MDD‐B. The L and M directions are most reliably determined by MVA‐ve when the spacecraft observes a clear electron jet reversal. When the magnetic field data have errors as small as 0.5% of the background field strength, the M direction obtained by MDD‐B technique may be off by as much as 35°. The normal direction is most accurately obtained by MDD‐B. Overall, we find that these techniques were able to identify EM from the virtual data within error bars ≥20%.
Key Points
The reconnection rate EM is estimated for one event using several techniques to find an M direction
The error bars in EM and the LMN coordinate directions are estimated from virtual data
The reconnection rate is likely EM = 3.2 mV/m ± 0.6 mV/m, which corresponds to a normalized rate of 0.18 ± 0.035
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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