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The $^{18}$O$/^{17}$O abundance ratio is, in principle, a powerful tool to estimate the relative contributions of massive stars and low- to intermediate-mass stars to the chemical enrichment of galaxies. We present $^{18}$O$/^{17}$O ratios derived from simultaneous observations of C$^{18}$O and C$^{17}$O 1-0 toward fifty-one massive star forming regions with the Institut de Radioastronomie Millim\'etrique (IRAM) 30 meter telescope. Simultaneous observations of HC$^{18}$O$^{+}$ 1-0 and HC$^{17}$O$^{+}$ 1-0 with the Yebes 40m telescope toward five sources from this sample were also done to test the consistency of $^{18}$O$/^{17}$O ratios derived from different isotopic pairs. From our improved measurements, resulting in smaller errors than previous work in the literature, we obtain a clear trend of increasing $^{18}$O$/^{17}$O ratio with increasing galactocentric distance (D$_{GC}$), which provides a significant constraint on Galactic chemical evolution (GCE) models. Current GCE models have to be improved in order to explain the observed C$^{18}$O/C$^{17}$O 1-0 gradient., Comment: 15 pages, 5 figures, 1 table, Accepted for publication in MNRAS

The line widths of broad line regions (BLRs) of AGNs are key parameters for understanding the central super massive black holes (SMBHs). However, due to obscuration from dusty torus, optical recombination lines from BLRs in type II AGNs can not be directly detected. Radio recombination lines (RRLs), with low extinction, can be ideal tracers to probe emission from BLRs in type II AGNs. We performed RRL observations for H35$\alpha$ and H36$\alpha$ toward the center of Circinus galaxy with ALMA. Narrow components of H35$\alpha$ and H36$\alpha$, which are thought to be mainly from star forming regions around the nuclear region, are detected. However, only upper limits are obtained for broad H35$\alpha$ and H36$\alpha$. Since Circinus galaxy is one of the nearest AGN, non-detection of broad RRLs in Circinus galaxy at this band tells us that it is hopeless to detect broad RRL emission in local AGNs with current facilities. Submillimetre RRLs, with flux densities that are dozens of times higher than those at the millimetre level, could be the tools to directly detect BLRs in type II AGNs with ALMA, once its backend frequency coverage has been upgraded to several times better than its current capabilities., Comment: 5 pages, 2 Figures, published in MNRAS Letters

We present new 3-mm continuum and molecular lines observations from the ATOMS survey towards the massive protostellar clump, MM1, located in the filamentary infrared dark cloud (IRDC), G034.43+00.24 (G34). The lines observed are the tracers of either dense gas (e.g. HCO+/H13CO+ J = 1-0) or outflows (e.g. CS J = 2-1). The most complete picture to date of seven cores in MM1 is revealed by dust continuum emission. These cores are found to be gravitationally bound, with virial parameter, $\alpha_{vir}, Comment: 14 pages with 6 figures, and in press

We present CO observations toward a sample of six HI-rich Ultra-diffuse galaxies (UDGs) as well as one UDG (VLSB-A) in the Virgo Cluster with the IRAM 30-m telescope. CO 1-0 is marginally detected at 4sigma level in AGC122966, as the first detection of CO emission in UDGs. We estimate upper limits of molecular mass in other galaxies from the non-detection of CO lines. These upper limits and the marginal CO detection in AGC122966 indicate low mass ratios between molecular and atomic gas masses. With the star formation efficiency derived from the molecular gas, we suggest that the inefficiency of star formation in such HI-rich UDGs is likely caused by the low efficiency in converting molecules from atomic gas, instead of low efficiency in forming stars from molecular gas., Comment: accepted by MNRAS letters

We present 1 and 3 mm observations of the 13C- and 15N-bearing isotopologues of dense gas tracers towards eight nearby infrared-bright galaxies. With the Institut de Radioastronomie Millimétrique 30-m telescope, we observed the J = 1–0 transitions of H13CN, HC15N, H13CO+, HN13C, and H15NC towards M 82, NGC 3079, IC 694, Mrk 231, and NGC 6240. The J = 3–2 transition of H13CN was obtained in M 82, NGC 3079, NGC 3504, NGC 4418, NGC 6240, and NGC 6946, using the 10-m Submillimeter Telescope (SMT). We report the first detections of HN13C J = 1–0 and H13CN J = 3–2 in M 82, and H13CN J = 3–2 in NGC 6240 and NGC 3079. We find different line profiles between the J = 1–0 and 3–2 transitions of H13CN in both M 82 and NGC 3079. The optical depths of HCN show significant variations among the sample, indicating that dense gas masses estimated from the line luminosities of HCN J = 1–0 and 3–2 should be treated with caution for individual galaxies. Optical depth of HCN J = 3–2 is found to be higher than that of HCN J = 1–0 in M 82, NGC 3079, NGC 4418, and NGC 6240, which indicates that ground state transitions of dense gas tracers might better trace the star-forming gas than the high-J transitions. Based on the H13CN/HC15N line ratios, with the double-isotopic method, low 14N/15N abundance ratios of 120 and 140 are found in NGC 3079 and Mrk 231, respectively.

We performed high-sensitivity mapping observations of several complex organic molecules around Sagittarius B2 with ARO 12m telescope at 3-mm wavelength. Based on their spatial distribution, molecules can be classified as either "extended" that detected not only in Sgr B2(N) and Sgr B2(M), or "compact" that only detected toward or near to Sgr B2(N) and Sgr B2(M). The "extended" molecules including glycolaldehyde (CH2OHCHO), methyl formate (CH3OCHO), formic acid (t-HCOOH), ethanol (C2H5OH) and methyl amine (CH3NH2), while the "compact" molecules including dimethyl ether (CH3OCH3), ethyl cyanide (C2H5CN), and amino acetonitrile (H2NCH2CN). These "compact" molecules are likely produced under strong UV radiation, while "extended" molecules are likely formed under low-temperature, via gas-phase or grain surface reactions. The spatial distribution of "warm" CH2OHCHO at 89 GHz differ from the spatial distribution of "cold" CH2OHCHO observed at 13 GHz. We found evidence for an overabundance of CH2OHCHO compared to that expected from the gas-phase model, which indicates that grain-surface reactions are necessary to explain the origin of CH2OHCHO in Sagittarius B2. Grain-surface reactions are also needed to explain the correlation between the abundances of "cold" CH2OHCHO and C2H5OH. These results demonstrate the importance of grain-surface chemistry in the production of complex organic molecules., Comment: 11 pages, accepted by MNRAS

Background Patient delay in seeking help has been reported to be a major factor that related to delay in care of acute myocardial infarction (AMI). Lack the knowledge of symptoms may translate to behavioral deficiencies which lead up to failing to seek medical assistant at early stage of AMI. Purpose The aim of present study is to investigate the awareness of AMI symptoms and the emergency responses among community residents over 35 years old. Methods The sample was proportionally distributed by age according to the national census data. The sex ratio was 1:1. The sample size is calculated according to the significance level of 0.05, the allowable error of 0.1, and the estimated Excellent awareness level of 10%. The final sample size is adjusted to 4200, considering non-response rate of 20%. Multi-stage stratified random sampling was used. On the first stage, two districts each in urban and rural regions were randomly selected. On the second stage, 3–10 community health service centers were randomly selected in each district. On the third stage, residents over 35 managed by the community health service center were proportionally sampled to be interviewed. A structured questionnaire was used and the survey was conducted in a face-to-face interview by clinical physicians. Logistic regression was applied to analyze factors related to Good knowledge. Results The top three symptom recognized by public is “pain or discomfort in the chest” (71.3%), followed by “difficulty breathing” (65.1%) and “pain or discomfort in the jaw, neck, or back” (60.9%). 85.0% chose to call an ambulance as first response when witness others having an AMI. Those who lives alone (OR=1.408; 95% CI, 1.005–1.972) and whose immediate family had been diagnosed with AMI (OR=1.510; 95% CI, 1.040–2.192) has better knowledge. A significant positive correlation was observed for those with hypertension (OR=1.199; 95% CI, 1.007–1.429), while a negative correlation was observed for those with diabetes (OR=0.788; 95% CI, 0.626–0.992). Public education could improve Good knowledge (OR=1.662; 95% CI, 1.388–1.990), while doctoral advise has been shown negative impact (OR=0.824; 95% CI, 0.691–0.984). Conclusions Our data provide first population-based estimates of public awareness in our country. Further promotional strategies to increase overall awareness in general public are seriously needed. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Major Science and Technology Projects of Tianjin Science and Technology Commission Multivariable logistic regression

Background The high cost and insufficient supply of human papillomavirus (HPV) vaccines have slowed the pace of controlling cervical cancer. A phase III clinical trial was conducted to evaluate the efficacy, safety, and immunogenicity of a novel Escherichia coli-produced bivalent HPV-16/18 vaccine. Methods A multicenter, randomized, double-blind trial started on November 22, 2012 in China. In total, 7372 eligible women aged 18–45 years were age-stratified and randomly assigned to receive three doses of the test or control (hepatitis E) vaccine at months 0, 1, and 6. Co-primary endpoints included high-grade genital lesions and persistent infection (over 6 months) associated with HPV-16/18. The primary analysis was performed on a per-protocol susceptible population of individuals who were negative for relevant HPV type-specific neutralizing antibodies (at day 0) and DNA (at day 0 through month 7) and who received three doses of the vaccine. This report presents data from a prespecified interim analysis used for regulatory submission. Results In the per-protocol cohort, the efficacies against high-grade genital lesions and persistent infection were 100.0% (95% confidence interval = 55.6% to 100.0%, 0 of 3306 in the vaccine group vs 10 of 3296 in the control group) and 97.8% (95% confidence interval = 87.1% to 99.9%, 1 of 3240 vs 45 of 3246), respectively. The side effects were mild. No vaccine-related serious adverse events were noted. Robust antibody responses for both types were induced and persisted for at least 42 months. Conclusions The E coli-produced HPV-16/18 vaccine is well tolerated and highly efficacious against HPV-16/18–associated high-grade genital lesions and persistent infection in women.

Previous observations have shown that the distribution of 36.2-GHz class I methanol megamaser (MM) emission in Arp 220 is highly correlated with the diffuse X-rays. On this basis it was suggested that methanol MM may be produced either by the effects of galactic-outflow-driven shocks and/or cosmic rays. Here we report the results of a single-dish survey undertaken with the Greenbank Telescope (GBT) to improve our understanding of the pumping conditions of extragalactic class I methanol masers and their relationship to starburst and feedback processes within the host galaxies, towards a sample which includes 16 galaxies which show both extended soft X-ray emission, and either OH or H2O MM emission. Large baseline ripples in the GBT spectra limited our results to tentative detections towards 11 of the target galaxies. Analysis of these tentative detections shows that there are significant correlations between the methanol intensity and the host-galaxy infrared, radio and OH MM emission, but no correlation with the X-ray and H2O MM emission. Some sources show methanol emission significantly offset from the systemic velocity of the galaxy (by up to 1000 km s−1) and we propose that these are associated with galactic-scale outflows from active galactic nuclei (AGNs) feedback. The combined observational properties suggest that class I methanol MMs are related to significant starburst and molecular outflow activity and hence may provide a potential probe of AGN feedback and starburst processes in the host galaxies.

We present observations of isotopologue lines of dense-gas tracers at 3 mm and 1 mm towards the nearest ultra-luminous infrared galaxy Arp 220. The 3-mm and 1-mm observations were performed with the Institut de Radioastronomie Millimetrique 30-m telescope and the Atacama Pathfinder Experiment 12-m telescope, respectively. We detected (HCN)-C-13 and (HNC)-C-13 in 1-0 and 3-2, and (HCN)-N-15 1-0, among which (HCN)-N-15 1-0 and (HNC)-C-13 1-0 are detected in Arp 220 for the first time. The (HCO+)-C-13 1-0 and 3-2 lines are unlikely to be detected because of the confusion of SiO lines. We find that the ratio of the line brightness temperatures of (HNC)-C-13 3-2/1-0 is 2.4, which is significantly higher than that of (HCN)-C-13 3-2/1-0 (0.73). This indicates that (HNC)-C-13 and HNC molecules are in denser regions than (HCN)-C-13 and HCN molecules. With the line ratio of (HCN)-C-13 1-0 and (HCN)-N-15 1-0, the N-14/N-15 ratio was estimated to be 440(-82)(+140), which is larger than that of the local interstellar medium.

We present 3-mm observations obtained with the Institut de Radioastronomie Millimetrique (IRAM) 30-m telescope for 10 nearby gas-rich active galaxies spanning three orders of magnitude in infrared luminosity. Emission lines of HCO+(1–0), HCN(1–0) and C2H(1–0) were simultaneously detected in most galaxies of our sample. We also tentatively detected the rare isotopic species H13CN, HC15N and H13CO+ in up to four galaxies (IC 694, NGC 3690, NGC 4258 and NGC 6240). Our estimation shows that the optical depth of HCN is low to moderate in these galaxies (τ∼ 1–5). After comparing the intensity ratios of different molecular emission lines (HCN/HCO+, C2H/HCN and C2H/HCO+) with the infrared luminosity (LIR), we find that in the infrared luminous sample of five composite (AGN+starburst) galaxies these ratios vary with LIR: the HCN/HCO+ ratio increases with LIR, which is consistent with previous studies, while there is a slight trend in the composite galaxies that both C2H/HCN and C2H/HCO+ ratios decrease with increasing LIR. Although our sample is limited, this trend may possibly imply a relation between the overall gas density and the infrared luminosity of galaxies.

With the observations of the CS 5-4 line toward a sample of 24 infrared bright galaxies using HHSMT, we detected CS 5-4 emission in 14 galaxies, including 12 ULIRGs/LIRGs and 2 nearby normal galaxies. As a good dense gas tracer, which has been well used for studying star formation in the Milky Way, CS 5-4 can trace the active star forming gas in galaxies. The correlation between CS 5-4 luminosity, which is estimated with detected CS 5-4 line emission, and infrared luminosity in these 14 galaxies is fitted with correlation coefficient of 0.939 and the slope close to unity. This correlation confirmed that dense gas, which is closely linked to star formation, is very important for understanding star formation in galaxies.