Protein termini are determinants of protein stability. Proteins bearing degradation signals, or degrons, at their amino‐ or carboxyl‐termini are eliminated by the N‐ or C‐degron pathways, ...respectively. We aimed to elucidate the function of C‐degron pathways and to unveil how normal proteomes are exempt from C‐degron pathway‐mediated destruction. Our data reveal that C‐degron pathways remove mislocalized cellular proteins and cleavage products of deubiquitinating enzymes. Furthermore, the C‐degron and N‐degron pathways cooperate in protein removal. Proteome analysis revealed a shortfall in normal proteins targeted by C‐degron pathways, but not of defective proteins, suggesting proteolysis‐based immunity as a constraint for protein evolution/selection. Our work highlights the importance of protein termini for protein quality surveillance, and the relationship between the functional proteome and protein degradation pathways.
SYNOPSIS
Proteins with degradation signals (degron) at their amino‐ or carboxyl‐termini are eliminated by the N‐ or C‐degron pathways, respectively. Proteome‐wide analyses suggest functions of human C‐degrons signals in protein quality surveillance, as well as interplay with N‐degron‐dependent mechanisms.
The Global Protein Stability (GPS) random peptide platform enables context‐independent characterization of degron features.
The activity of C‐degrons is tuned by their surrounding sequences.
Gly/C‐degron shortage is limited to functional eukaryotic proteomes accessible to C‐degron pathways.
C‐degron pathways clear products of proteases and mislocalized cellular proteins.
Mitochondrial localization of MIC19 is dually safeguarded by the N‐ and C‐degron pathways.
Coronaviral diGly‐ending proteins evade C‐degron pathway‐mediated degradation.
Proteome‐wide analyses suggest functions of C‐terminal degradation signals in protein quality surveillance as well as interplay with N‐degron‐dependent mechanisms.
The photometric light curves of BRITE satellites were examined through a machine learning technique to investigate whether there are possible exoplanets moving around nearby bright stars. Focusing on ...different transit periods, several convolutional neural networks were constructed to search for transit candidates. The convolutional neural networks were trained with synthetic transit signals combined with BRITE light curves until the accuracy rate was higher than 99.7%. Our method could efficiently lead to a small number of possible transit candidates. Among these ten candidates, two of them, HD37465, and HD186882 systems, were followed up through future observations with a higher priority. The codes of convolutional neural networks employed in this study are publicly available at http://www.phys.nthu.edu.tw/~jiang/BRITE2020YehJiangCNN.tar.gz.
Abstract
We present a transit-timing variation (TTV) and planetary atmosphere analysis of the Neptune-mass planet HAT-P-26 b. We present a new set of 13 transit light curves from optical ground-based ...observations and combine them with light curves from the Wide Field Camera 3 on the Hubble Space Telescope, the Transiting Exoplanet Survey Satellite, and previously published ground-based data. We refine the planetary parameters of HAT-P-26 b and undertake a TTV analysis using 33 transits obtained over seven years. The TTV analysis shows an amplitude signal of 1.98 ± 0.05 minutes, which could result from the presence of an additional ∼0.02
M
Jup
planet at a 1:2 mean-motion resonance orbit. Using a combination of transit depths spanning optical to near-infrared wavelengths, we find that the atmosphere of HAT-P-26 b contains
2.4
−
1.6
+
2.9
% H
2
O with a derived temperature of
590
−
50
+
60
K.
This study aimed to investigate the perceived work stress and its influencing factors among hospital staff during the novel coronavirus (COVID‐19) pandemic in Taiwan. A web‐based survey was conducted ...at one medical center and two regional hospitals in southern Taiwan, targeting physicians, nurses, medical examiners, and administrators. The questionnaire included items on the demographic characteristics of hospital staff and a scale to assess stress among healthcare workers caring for patients with a highly infectious disease. A total of 752 valid questionnaires were collected. The hospital staff reported a moderate level of stress and nurses had a highest level of stress compared to staff in the other three occupational categories. The five highest stress scores were observed for the items “rough and cracked hands due to frequent hand washing and disinfectant use,” “inconvenience in using the toilet at work,” “restrictions on eating and drinking at work,” “fear of transmitting the disease to relatives and friends,” and “fear of being infected with COVID‐19.” Discomfort caused by protective equipment was the major stressor for the participants, followed by burden of caring for patients. Among participants who experienced severe stress (n = 129), work stress was higher among those with rather than without minor children. The present findings may serve as a reference for future monitoring of hospital staff's workload, and may aid the provision of support and interventions.
ABSTRACT
We report the conditional occurrences between three planetary types: super-Earths (m sin i < 10 M⊕, P < 100 d), warm Jupiters (m sin i > 95 M⊕, 10 < P < 100 d), and cold Jupiters (m sin i > ...95 M⊕, P > 400 d) for sun-like stars. We find that while the occurrence of cold Jupiters in systems with super-Earths is $22.2\substack{+8.3 \\ -5.4}$ per cent, compared to 10 per cent for the absolute occurrence rate of cold Jupiters, the occurrence of super-Earths in systems with cold Jupiters is $66.0\substack{+18.0 \\ -16.0}$ per cent, compared to 30 per cent for the absolute occurrence rate of super-Earths for Sun-like stars. We find that the enhancement of super-Earths in systems with cold Jupiters is evident for Sun-like stars, in agreement with several previous studies. We also conduct occurrence studies between warm Jupiters and super-Earths, and between warm Jupiters and cold Jupiters, to consolidate our methods. We conduct an independent observational test to study the effects of cold Jupiters against the inner multiplicity using the well-established giant planet host star metallicity correlation for all transiting planets found to date. The conditional occurrences we find here can be used to constrain the validity of various planetary formation models. The extremely interesting correlations between the super-Earths, cold Jupiters, and warm Jupiters can also be used to understand the formation histories of these planetary types.
We present 12 new transit light curves of the hot-Jupiter TrES-3b observed during 2012−2018 to probe the transit timing variation (TTV). By combining the midtransit times determined from these 12 ...transit data with those reestimated through uniform procedure from 71 transit data available in the literature, we derive new linear ephemeris and obtain the timing residuals that suggest the possibility of TTV in the TrES-3 system. However, the frequency analysis shows that the possible TTV is unlikely to be periodic, indicating the absence of an additional body in this system. To explore the other possible origins of TTV, the orbital decay and apsidal precession ephemeris models are fitted to the transit time data. We find the decay rate of TrES-3b to be ms yr−1, and the corresponding estimated modified stellar tidal quality factor of is consistent with the theoretically predicted values for the stars hosting the hot-Jupiters. The shift in the transit arrival time of TrES-3b after 11 years is expected to be Tshift ∼ 69.55 s, which is consistent with the rms of the timing residuals. Besides, we find that the apsidal precession ephemeris model is statistically less probable than the other considered ephemeris models. It is also discussed that despite the fact that the linear ephemeris model appears to be the most plausible model to represent the transit time data, the possibility of the orbital decay cannot be completely ruled out in the TrES-3 system. To confirm this, further high-precision and high-cadence follow-up observation of transits of TrES-3b would be important.
The association between pancreatitis and acute myocardial infarction or stroke remains incompletely understood. This study aimed to evaluate the long-term risk of acute atherosclerotic cardiovascular ...disease (ASCVD) in people with acute and chronic pancreatitis. Using research database of Taiwan's National Health Insurance, we identified 2678 patients aged ≥ 20 years with newly diagnosed pancreatitis in 2000-2008. A cohort of 10,825 adults without pancreatitis was selected for comparison, with matching by age and sex. Both cohorts were followed from 2000 to the end of 2013, and incident acute ASCVD was identified during the follow-up period. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of acute ASCVD associated with pancreatitis were calculated. Compared with the comparison cohort, the adjusted HR of acute ASCVD were 1.76 (95% CI 1.47-2.12) and 3.42 (95% CI 1.69-6.94) for people with acute pancreatitis and chronic pancreatitis, respectively. A history of alcohol-related illness (HR 9.49, 95% CI 3.78-23.8), liver cirrhosis (HR 7.31, 95% CI 1.81-29.5), and diabetes (HR 6.89, 95% CI 2.18-21.8) may worsen the risk of acute ASCVD in patients with chronic pancreatitis. Compared with people had no pancreatitis, patients with acute pancreatitis who had alcohol-related illness (HR 4.66, 95% CI 3.24-6.70), liver cirrhosis (HR 4.44, 95% CI 3.05-6.47), and diabetes (HR 2.61, 95% CI 2.03-3.36) were at increased risk of acute ASCVD. However, the cumulative use of metformin was associated with a reduced risk of acute ASCVD in the acute pancreatitis cohort (HR 0.30, 95% CI 0.17-0.50). Compared with the control group, patients with acute or chronic pancreatitis were more likely to have an increased risk of acute ASCVD, while the use of metformin reduced the risk of acute ASCVD. Our findings warrant a survey and education on acute ASCVD for patients with acute and chronic pancreatitis.
Abstract
We present and analyze 58 transit light curves of TrES-3b and 98 transit light curves of Qatar-1b, observed by the Transiting Exoplanet Survey Satellite, plus two transit light curves of ...Qatar-1b, observed by us, using a ground-based 1.23 m telescope. These light curves are combined with the best-quality light curves taken from the Exoplanet Transit Database and the literature. The precisely determined midtransit times from these light curves enable us to obtain the refined orbital ephemerides, with improved precision, for both hot Jupiters. From the timing analysis, we find indications of the presence of transit timing variations (TTVs) in both systems. Since the observed TTVs are unlikely to be short-term and periodic, the possibility of additional planets in orbits close to TrES-3b and Qatar-1b is ruled out. The possible causes of long-term TTVs, such as orbital decay, apsidal precession, the Applegate mechanism, and line-of-sight acceleration, are also examined. However, none of these possibilities are found to explain the observed TTV of TrES-3b. In contrast to this, line-of-sight acceleration appears to be a plausible explanation for the observed TTV of Qatar-1b. In order to confirm these findings, further high-precision transit and radial velocity observations of both systems would be worthwhile.
Abstract
We perform transit timing variation (TTV) and transmission spectroscopy analyses of the planet HAT-P-37b, which is a hot Jupiter orbiting a G-type star. Nine new transit light curves are ...obtained and analyzed together with 21 published light curves from the literature. The updated physical parameters of HAT-P-37b are presented. The TTV analyses show a possibility that the system has an additional planet that induced the TTVs amplitude signal of 1.74 ± 0.17 minutes. If the body is located near the 1:2 mean-motion resonance orbit, the sinusoidal TTV signal could be caused by the gravitational interaction of a sub-Earth-mass planet with mass of 0.06
M
⊕
. From the analysis of an upper-mass limit for the second planet, a Saturn-mass planet with orbital period less than 6 days is excluded. The broadband transmission spectra of HAT-P-37b favors a cloudy atmospheric model with an outlier spectrum in the
B
filter.
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