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C _4 H and c -C _3 H _2 , as unsaturated hydrocarbon molecules, are important for forming large organic molecules in the interstellar medium. We present mapping observations of C _4 H ( N = 9−8) lines, c -C _3 H _2 ( J _Ka _, _Kb = 2 _1,2 –1 _0,1 ), and H ^13 CO ^+ ( J = 1−0) toward 19 nearby cold molecular cores in the Milky Way with the IRAM 30 m telescope. C _4 H 9–8 was detected in 13 sources, while c -C _3 H _2 was detected in 18 sources. The widely existing C _4 H and c -C _3 H _2 molecules in cold cores provide material to form large organic molecules. Different spatial distributions between C _4 H 9–8 and c -C _3 H _2 2–1 were found. The relative abundances of these three molecules were obtained under the assumption of local thermodynamic equilibrium conditions with a fixed excitation temperature. The abundance ratio of C _4 H to c -C _3 H _2 ranged from 0.34 ± 0.09 in G032.93+02 to 4.65 ± 0.50 in G008.67+22. A weak correlation between C _4 H/H ^13 CO ^+ and c -C _3 H _2 /H ^13 CO ^+ abundance ratios was found, with a correlation coefficient of 0.46, which indicates that there is no tight astrochemical connection between C _4 H and c -C _3 H _2 molecules.

In this letter, we report the discovery of a fast neutral hydrogen outflow in SDSS J145239.38+062738.0, a merging radio galaxy containing an optical type I active galactic nucleus (AGN). This discovery was made through observations conducted by the Five-hundred-meter Aperture Spherical radio Telescope (FAST) using redshifted 21 cm absorption. The outflow exhibits a blueshifted velocity likely up to ∼−1000 km s ^−1 with respect to the systemic velocity of the host galaxy with an absorption strength of ∼−0.6 mJy beam ^−1 corresponding to an optical depth of 0.002 at v = −500 km s ^−1 . The mass outflow rate ranges between 2.8 × 10 ^−2 and 3.6 M _⊙ yr ^−1 , implying an energy outflow rate ranging between 4.2 × 10 ^39 and 9.7 × 10 ^40 erg s ^−1 , assuming 100 K < T _s < 1000 K. Plausible drivers of the outflow include the starbursts, AGN radiation, and radio jet, the last of which is considered the most likely culprit according to the kinematics. By analyzing the properties of the outflow, AGN, and jet, we find that if the H i outflow is driven by the AGN radiation, the AGN radiation does not seem powerful enough to provide negative feedback, whereas the radio jet shows the potential to provide negative feedback. Our observations contribute another example of a fast outflow detected in neutral hydrogen and demonstrate the capability of FAST in detecting such outflows.

Taking both individual and team levels into consideration has been called for years in terms of research on leadership. Inclusive leadership, a trending leadership style emerging from the global needs of managing the increasingly diversified workplace nowadays, has yet been rarely studied at both levels. To answer these calls, we specifically analyzed the relationship between inclusive leadership, team psychological safety, and innovative performance via a multilevel analysis. The results are based on a study of 356 employees from 90 working teams. Individual perceptions of inclusive leadership are positively related to the individual innovative performance through the mediation of individual psychological safety. Team perceptions of inclusive leadership are positively related to the team innovative performance through the mediation of team psychological safety. Moreover, team perceptions of inclusive leadership are positively related to the individual innovative performance through the cross-level mediation of individual psychological safety. Implications for both theory and practice are discussed.

BackgroundAn increasing number of geriatric patients are suffering from degenerative lumbar spondylolisthesis (DLS) and need a lumbar interbody fusion (LIF) operation to alleviate the symptoms. Our study was performed aiming to determine the predictors that contributed to unfavorable clinical efficacy among patients with DLS after LIF according to the support vector machine (SVM) algorithm.MethodsA total of 157 patients with single-segment DLS were recruited and performed LIF in our hospital from January 1, 2015 to October 1, 2020. Postoperative functional evaluation, including ODI and VAS were, performed, and endpoint events were defined as significant relief of symptom in the short term (2 weeks postoperatively) and long term (1 year postoperatively). General patient information and radiological data were selected and analyzed for statistical relationships with the endpoint events. The SVM method was used to establish the predictive model.ResultsAmong the 157 consecutive patients, a postoperative unfavorable clinical outcome was reported in 26 patients (16.6%) for a short-term cohort and nine patients (5.7%) for a long-term cohort. Based on univariate and multivariate regression analysis, increased disc height (DH), enlarged facet angle (FA), and raised lateral listhesis (LLS) grade were confirmed as the risk factors that hindered patients' short-term functional recovery. Furthermore, long-term functional recovery was significantly associated with DH alone. In combination with the SVM method, a prediction model with consistent and superior predictive performance was achieved with average and maximum areas under the receiver operating characteristic curve (AUC) of 0.88 and 0.96 in the short-term cohort, and 0.78 and 0.82 in the long-term cohort. The classification results of the discriminant analysis were demonstrated by the confusion matrix.ConclusionsThe proposed SVM model indicated that DH, FA, and LLS were statistically associated with a clinical outcome of DLS. These results may provide optimized clinical strategy for treatment of DLS.

Ions (e.g., ${{\rm{H}}}_{3}^{+}$ , H _2 O ^+ ) have been used extensively to quantify the cosmic-ray ionization rate (CRIR) in diffuse sightlines. However, measurements of the CRIR in low-to-intermediate density gas environments are rare, especially when background stars are absent. In this work, we combine molecular line observations of CO, OH, CH, and HCO ^+ in the star-forming cloud IC 348, and chemical models to constrain the value of the CRIR and study the response of the distribution of chemical abundances. The cloud boundary is found to have an A _V of approximately 4 mag. From the interior to the exterior of the cloud, the observed ^13 CO line intensities drop by an order of magnitude. The calculated average abundance of ^12 CO (assuming ^12 C/ ^13 C=65) is (1.2 ± 0.9) × 10 ^−4 , which decreases by a factor of 6 from the interior to the outside regions. The average abundance of CH (3.3 ± 0.7 × 10 ^−8 ) is in good agreement with previous findings in diffuse and translucent clouds ( A _V < 5 mag). However, we did not find a decline in CH abundance in regions of high extinction ( A _V ≃ 8 mag) as previously reported in Taurus. By comparing the observed molecular abundances and chemical models, we find a decreasing trend of the CRIR as A _V increases. The inferred CRIR of ζ _cr = (4.7 ± 1.5) × 10 ^−16 s ^−1 at low A _V is consistent with ${{\rm{H}}}_{3}^{+}$ measurements toward two nearby massive stars.

The cosmic-ray ionization rate (CRIR, ζ _2 ) is one of the key parameters controlling the formation and destruction of various molecules in molecular clouds. However, the current most commonly used CRIR tracers, such as ${{\rm{H}}}_{3}^{+}$ , OH ^+ , and H _2 O ^+ , are hard to detect and require the presence of background massive stars for absorption measurements. In this work, we propose an alternative method to infer the CRIR in diffuse clouds using the abundance ratios of OH/CO and HCO ^+ /CO. We have analyzed the response of chemical abundances of CO, OH, and HCO ^+ on various environmental parameters of the interstellar medium in diffuse clouds and found that their abundances are proportional to ζ _2 . Our analytic expressions give an excellent calculation of the abundance of OH for ζ _2 ≤ 10 ^−15 s ^−1 , which are potentially useful for modeling chemistry in hydrodynamical simulations. The abundances of OH and HCO ^+ were found to monotonically decrease with increasing density, while the CO abundance shows the opposite trend. With high-sensitivity absorption transitions of both CO (1–0) and (2–1) lines from Atacama Large Millimeter/submillimeter Array, we have derived the H _2 number densities ( ${n}_{{{\rm{H}}}_{2}}$ ) toward 4 lines of sight; assuming a kinetic temperature of T _k = 50 K, we find a range of (0.14 ± 0.03–1.2 ± 0.1) × 10 ^2 cm ^−3 . By comparing the observed and modeled HCO ^+ /CO ratios, we find that ζ _2 in our diffuse gas sample is in the range of ${1.0}_{-1.0}^{+14.8}$ × 10 ${}^{-16}\mbox{--}{2.5}_{-2.4}^{+1.4}$ × 10 ^−15 s ^−1 . This is ∼2 times higher than the average value measured at higher extinction, supporting an attenuation of CRs as suggested by theoretical models.

Purpose — The purpose of this research is to investigate how generalisable the public service motivation (PSM) observed in Western society is to China and to examine the effects of public service motivation on job satisfaction. Design/methodology/approach — Exploratory factor analysis and confirmatory factor analysis techniques are applied to survey data of 191 public servants in China to investigate the generalisability of Western PSM. Using hierarchical regression analysis, the paper examines the effects of the dimensions of PSM on job satisfaction. Findings — The results show that the public service motivation observed in the West exists in China, but the generalisability of the construct is limited. Three of the four dimensions of public service motivation (attraction to public policy making, commitment to the public interest, and self-sacrifice) exist in China, but the fourth dimension (compassion) is unconfirmed. Originality/value — The paper is the first to examine the generalisability and instrumentality of PSM as observed in Western society to China. The results indicate that the public service motivation observed in the West also exists in China, but that the generalisability is limited. Public service motivation emerges from the results as a positively significant predictor of job satisfaction in the public sector of China. It enhances the applicability and meaningfulness of the concept of public service motivation across political and cultural environments. [ABSTRACT FROM AUTHOR]

We present an observational study of the sulfur (S)-bearing species toward Orion KL at 1.3 mm by combining ALMA and IRAM-30 m single-dish data. At a linear resolution of ∼800 au and a velocity resolution of 1 km s−1, we have identified 79 molecular lines from six S-bearing species. In these S-bearing species, we found a clear dichotomy between carbon–sulfur compounds and carbon-free S-bearing species for various characteristics, e.g., of line profiles, spatial morphology, and molecular abundances with respect to H2. Lines from the carbon–sulfur compounds (i.e., OCS, 13CS, and H2CS) exhibit spatial distributions concentrated around the continuum peaks and extended to the south ridge. The full width at half maximum (FWHM) linewidth of these molecular lines is in the range of 2 ∼11 km s−1. The molecular abundances of OCS and H2CS decrease slightly from the cold (∼68 K) to the hot (∼176 K) regions. In contrast, lines from the carbon-free S-bearing species (i.e., SO2, 34SO, and H2S) are spatially more extended to the northeast of mm4, exhibiting broader FWHM line widths (15 ∼ 26 km s−1). The molecular abundances of carbon-free S-bearing species increase by over an order of magnitude as the temperature increase from 50 to 100 K. In particular, 34SO/34SO2 and OCS/SO2 are enhanced from the warmer regions (>100 K) to the colder regions (∼50 K). Such enhancements are consistent with the transformation of SO2 at warmer regions and the influence of shocks. [ABSTRACT FROM AUTHOR]

Observations of interstellar dust are often used as a proxy for total gas column density NH. By comparing Planck thermal dust data (Release 1.2) and new dust reddening maps from Pan-STARRS 1 and 2MASS, with accurate (opacity-corrected) H i column densities and newly published OH data from the Arecibo Millennium survey and 21-SPONGE, we confirm linear correlations between dust optical depth τ353, reddening E(B − V), and the total proton column density NH in the range (1–30) × 1020 cm−2, along sightlines with no molecular gas detections in emission. We derive an NH/E(B − V) ratio of (9.4 ± 1.6) × 1021 cm−2 mag−1 for purely atomic sightlines at , which is 60% higher than the canonical value of Bohlin et al. We report a ∼40% increase in opacity σ353 = τ353/NH, when moving from the low column density (NH < 5 × 1020 cm−2) to the moderate column density (NH > 5 × 1020 cm−2) regime, and suggest that this rise is due to the evolution of dust grains in the atomic interstellar medium. Failure to account for H i opacity can cause an additional apparent rise in σ353 of the order of a further ∼20%. We estimate molecular hydrogen column densities from our derived linear relations, and hence derive the OH/H2 abundance ratio of XOH ∼ 1 × 10−7 for all molecular sightlines. Our results show no evidence of systematic trends in OH abundance with in the range ∼ (0.1−10) × 1021 cm−2. This suggests that OH may be used as a reliable proxy for H2 in this range, which includes sightlines with both CO-dark and CO-bright gas. [ABSTRACT FROM AUTHOR]

We have obtained OH spectra of four transitions in the ground state, at 1612, 1665, 1667, and 1720 MHz, toward 51 sightlines that were observed in the Herschel project Galactic Observations of Terahertz C+. The observations cover the longitude range of (32°, 64°) and (189°, 207°) in the northern Galactic plane. All of the diffuse OH emissions conform to the so-called “Sum Rule” of the four brightness temperatures, indicating optically thin emission conditions for OH from diffuse clouds in the Galactic plane. The column densities of the H i “halos” N(H i) surrounding molecular clouds increase monotonically with OH column density, N(OH), until saturating when cm−2 and cm−2, indicating the presence of molecular gas that cannot be traced by H i. Such a linear correlation, albeit weak, is suggestive of halos’ contribution to the UV shielding required for molecular formation. About 18% of OH clouds have no associated CO emission (CO-dark) at a sensitivity of 0.07 K, but are associated with C+ emission. A weak correlation exists between C+ intensity and OH column density for CO-dark molecular clouds. These results imply that OH seems to be a better tracer of molecular gas than CO in diffuse molecular regions. [ABSTRACT FROM AUTHOR]