Signs of outflow feedback from a nearby young stellar object on the protostellar envelope around HL Tau

HL Tau is a Class I-II protostar embedded in an infalling and rotating envelope and possibly associated with a planet forming disk, and it is co-located in a 0.1 pc molecular cloud with two nearby young stellar objects. Our ALMA observations revealed two arc-like structures on a 1000 au scale connected to the disk, and their kinematics could not be explained with any conventional model of infalling and rotational motions. In this work, we investigate the nature of these arc-like structures connected to the HL Tau disk. We conducted new observations in the 13CO and C18O (3-2; 2-1) lines with JCMT and IRAM 30m, and obtained the ACA data with the 7-m array. With the single-dish, ACA, and ALMA data, we analyzed the gas motions on both 0.1 pc and 1000 au scales in the HL Tau region. We constructed new kinematical models of an infalling and rotating envelope with the consideration of relative motion between HL Tau and the envelope. By including the relative motion between HL Tau and its protostellar envelope, our kinematical model can explain the observed velocity features in the arc-like structures. The morphologies of the arc-like structures can also be explained with an asymmetric initial density distribution in our model envelope. In addition, our single-dish results support that HL Tau is located at the edge of a large-scale (0.1 pc) expanding shell driven by the wind or outflow from XZ Tau, as suggested in the literature. The estimated expanding velocity of the shell is comparable to the relative velocity between HL Tau and its envelope in our kinematical model. These results hints that the large-scale expanding motion likely impacts the protostellar envelope around HL Tau and affects its gas kinematics. We found that the mass infalling rate from the envelope onto the HL Tau disk can be decreased by a factor of two due to this impact by the large-scale expanding shell.Comment: Accepted by A&

Gas kinematics and star formation in the filamentary molecular cloud G47.06+0.26

We performed a multi-wavelength study toward the filamentary cloud G47.06+0.26 to investigate the gas kinematics and star formation. We present the 12CO (J=1-0), 13CO (J=1-0) and C18O (J=1-0) observations of G47.06+0.26 obtained with the Purple Mountain Observation (PMO) 13.7 m radio telescope to investigate the detailed kinematics of the filament. The 12CO (J=1-0) and 13CO (J=1-0) emission of G47.06+0.26 appear to show a filamentary structure. The filament extends about 45 arcmin (58.1 pc) along the east-west direction. The mean width is about 6.8 pc, as traced by the 13CO (J=1-0) emission. G47.06+0.26 has a linear mass density of about 361.5 Msun/pc. The external pressure (due to neighboring bubbles and H II regions) may help preventing the filament from dispersing under the effects of turbulence. From the velocity-field map, we discern a velocity gradient perpendicular to G47.06+0.26. From the Bolocam Galactic Plane Survey (BGPS) catalog, we found nine BGPS sources in G47.06+0.26, that appear to these sources have sufficient mass to form massive stars. We obtained that the clump formation efficiency (CFE) is about 18% in the filament. Four infrared bubbles were found to be located in, and adjacent to, G47.06+0.26. Particularly, infrared bubble N98 shows a cometary structure. CO molecular gas adjacent to N98 also shows a very intense emission. H II regions associated with infrared bubbles can inject the energy to surrounding gas. We calculated the kinetic energy, ionization energy, and thermal energy of two H II regions in G47.06+0.26. From the GLIMPSE I catalog, we selected some Class I sources with an age of about 100000 yr, which are clustered along the filament. The feedback from the H II regions may cause the formation of a new generation of stars in filament G47.06+0.26.Comment: 10 pages, 11 figures, accepted for publication in A&

Coordinate Ascent for Off-Policy RL with Global Convergence Guarantees

We revisit the domain of off-policy policy optimization in RL from the perspective of coordinate ascent. One commonly-used approach is to leverage the off-policy policy gradient to optimize a surrogate objective -- the total discounted in expectation return of the target policy with respect to the state distribution of the behavior policy. However, this approach has been shown to suffer from the distribution mismatch issue, and therefore significant efforts are needed for correcting this mismatch either via state distribution correction or a counterfactual method. In this paper, we rethink off-policy learning via Coordinate Ascent Policy Optimization (CAPO), an off-policy actor-critic algorithm that decouples policy improvement from the state distribution of the behavior policy without using the policy gradient. This design obviates the need for distribution correction or importance sampling in the policy improvement step of off-policy policy gradient. We establish the global convergence of CAPO with general coordinate selection and then further quantify the convergence rates of several instances of CAPO with popular coordinate selection rules, including the cyclic and the randomized variants of CAPO. We then extend CAPO to neural policies for a more practical implementation. Through experiments, we demonstrate that CAPO provides a competitive approach to RL in practice.Comment: 47 pages, 4 figure

Unmasking stem-specific broadly neutralizing epitopes by abolishing N-linked glycosylation sites for vaccine design

Targeting highly conserved HA stem regions has been proposed as a useful strategy for designing universal influenza vaccines. The influenza virus HA stem region, consisting of a HA1 N-terminal part and full HA2 part, contains several potential sites for the addition of N-glycans. We expressed a series of recombinant HA (rHA) mutant proteins with deleted N-linked glycosylation sites in the HA1-stem and HA2-stem regions of H5N1 and pH1N1 viruses. Unmasking N-glycans in the HA2-stem region (rH5HA N484A and rH1HA N503A) did not affect the trimeric structure of HA. Immunizations using rH5HA N484A and rH1HA N503A elicited more potent neutralizing antibody titers against homologous, heterologous and heterosubtypic viruses. Unmasking the HA2-stem N-glycans of rH5HA N484A induced higher levels of stem-specific CR6261-like and FI6v3-like antibodies, improved the ability of stem-specific anti-fusion antibodies, enhanced H5 stem helix A epitope-specific B and T cell responses in splenocytes, and provided better protection against both homologous and heterosubtypic virus challenges. These findings suggest that HA2-stem N-glycan unmasking holds potential as a useful design strategy for developing more broadly protective influenza vaccines

The aldosterone index could be used to diagnose the dominant gland in primary aldosteronism — a retrospective study

Introduction: Failed cannulation in the right adrenal vein, which makes the sampling results in the contralateral vein and inferior vena cava (IVC) nonsense, is the main obstacle of using adrenal vein sampling (AVS) in the lateralisation diagnosis in primary aldosteronism (PA). We performed a retrospective study to evaluate the specificity and sensitivity of using the aldosterone index (AI) in PA lateralisation diagnosis. Material and methods: We enrolled 116 patients who were diagnosed with PA and then underwent AVS in the West China Hospital of Sichuan University from April 2015 to April 2017. The AI, calculated by dividing the aldosterone concentration of the failed side by the aldosterone concentration of IVC, was used for lateralisation diagnosis if the cannulation was judged to be failed by traditional method. Patients with dominant adrenal gland based on successful AVS were included in subgroup 2 (n = 75), while the patients diagnosed with a dominant gland using AI method were enrolled in subgroup 1 (n = 41). Results: No significant difference of clinical and biochemical findings between the two groups was detected (p value after operation > 0.05). ROC analysis was performed to test the specificity and sensitivity based on the AI in subgroup 2. The AUC for dominant gland detection was 0.76, which resulted in 91.3% sensitivity and 67.53% specificity. The positive and negative likelihood ratios were 2.81. Conclusions: Our data suggested that the modified strategy using AI to diagnose the dominant gland in PA is an efficient method when cannulation has failed in the right side

Screening Quality Evaluation Factors of Freeze-Dried Peach ( Prunus Persica

The quality evaluation of processed products is complex. To simplify the quality evaluation process and improve the efficiency, fourteen evaluation factors of freeze-dried powders of seventeen cultivars of peach at different ripening times were analyzed. The most important evaluation indicators and criteria were obtained by analysis of variance (ANOVA), correlation analysis (CA), principal component analysis (PCA), system cluster analysis (SCA), and analytic hierarchy process (AHP). Results showed that the peach powders had the significant differences in quality (P<0.05), and some processing factors were related with some physicochemical and nutritional factors. Five principle components were extracted by PCA and the cumulative contribution achieved was 84.46%. Through the score plot of the first two principal components, a clear differentiation among ripening times was found and three distinct groups were separated according to ripening time. Five characteristic factors were obtained as titratable acid, browning index, hemicellulose, hygroscopicity, and vitamin C by SCA. Their weights of 0.1249, 0.3007, 0.0514, 0.4916, and 0.0315 were obtained by AHP, respectively. The peach cultivars were divided into four evaluation grades by the comprehensive quality score