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Observations of HCN and HCO+ have been carried out toward 13 planetary nebulae (PNe) using the facilities of the Arizona Radio Observatory (ARO). These nebulae represent a wide range of morphologies and ages (∼2000â€"28,000 yr). For both molecules, the J = 1 â†' 0 transitions at 88â€"89 GHz and the J = 3 â†' 2 lines at 265â€"267 GHz were measured, together with CO lines (J = 1 â†' 0, 2 â†' 1, and 3 â†' 2, depending on the source), using the ARO 12 m and Submillimeter Telescopes. HCN and HCO+ were detected with at least one transition in 10 nebulae: He 2-459, Hu 1-1, K3-52, K3-65, M1-8, M1-40, M1-59, M2-53, M4-17, and NGC 6445. HCO+ was additionally identified via two transitions in Na 2. Some observed line profiles were complex, with multiple velocity components tracing varied outflows. From radiative transfer modeling, column densities were established for HCN and HCO+: N tot(HCN) = 0.005â€"1.1 Ă— 1014 and N tot(HCO+) = 0.008â€"9.5 Ă— 1013 cmâˆ'2. Gas densities of n (H2) ∼ 105â€"107 cmâˆ'3 were also determined for all PNe. Fractional abundances with respect to H2, calculated using CO as a proxy, are f (HCN) ∼ 0.2â€"1.5 Ă— 10âˆ'7 and f (HCO+) ∼ 0.3â€"5.1 Ă— 10âˆ'8. The abundances of HCN and HCO+ did not significantly vary with nebular age to 28,000 yr. Combined with previous observations, at least 30 PNe contain HCN and/or HCO+, indicating that polyatomic molecules are common constituents of these objects. The data strongly support a scenario where dense ejecta from PNe seed the interstellar medium with molecular material. [ABSTRACT FROM AUTHOR]

Abstract Aim There has been growing concern about the nurses' turnover intention as well as life satisfaction during COVID‐19 pandemic in Iran. The past research has provided evidence on the effect of organizational support on nurses' job satisfaction and turnover intention. However, little is known about the underlying mechanism behind these associations. Design A cross‐sectional survey was undertaken. Methods An online survey was conducted in Iran from May to June 2020 through Google Docs Forms. In total, 305 nurses were participated and completed the online survey. Data were analysed using structural equation modelling through (AMOS). This study was checked with the STROBE checklist. Result The results showed that nurses' perception of organizational support was positively related to their job satisfaction which in turn decreases the turnover intention. Likewise, the job satisfaction partially mediated the relationship between organizational support and nurses' life satisfaction.

Many a time, the relationship between China and Africa is stereotyped as an energy quest to sustain China’s economic growth, leading to anti-Chinese resistance narratives in Africa. Against this background, the observed presence of China in Nigeria, more specifically, warrants attention, as the strategic relationship has expanded significantly to emerge as a powerful, yet questionable, South-South alliance. We document the economic activities of China in Nigeria, through the channels of trade, foreign direct investment (FDI), and aid, to frame our understanding of the content of those ties. As the engagement of China in Nigeria is skewed towards the extractive industry, this paper mainly focuses on Nigeria’s oil sector, by tracing the transforming developments and addressing the challenges of Nigeria that relates with economic, environmental and social life, with China’s commercial presence in the oil sector. With the economic dimensions of this contextual engagement, we set out a research agenda that focuses on the effectiveness of commercial activities of China in the Nigerian oil sector.

China’s ascent influences the Western aid dynamic significantly and changes the landscape in aid-donor and aid-recipient relationship for resource-endowed countries in Africa. Similarly, within China-Africa relations, Nigeria established diplomatic relations with China in 2006 for a concessional oil-for-infrastructure plan to fill the development aperture. However, Nigeria opted out as political uncertainty and elite interest in rent-seeking supersedes development and well-being motive. We conclude that two interrelated causal factors – accountability and transparency – overwhelmingly obstruct Nigeria from optimising China interest in infrastructure development. The study recommends the review of National Planning Commission (NPC) 2007 ODA policy document on technical assistance, grants, and concessional loans to identify new problems and challenges associated with formulation and implementation of donor-assisted programmes.

The relation between the timing of do-not-resuscitate (DNR) orders and the cost of medical care is not well understood. This prospective observational study compares hospital costs and length of stay of 265 terminally ill patients with admission DNR orders, delayed DNR orders (occurring after 24 hours), or no DNR orders (full code). Patients whose orders remained full code throughout a hospital stay had similar lengths of stay, total hospital costs, and daily costs as patients with admission DNR orders. Patients with delayed DNR orders, by contrast, had a greater mortality, longer length of stay, and higher total costs than full code or admission DNR patients, but similar daily costs. The causes of delay in DNR orders and the associated higher costs are a matter for future research. [ABSTRACT FROM AUTHOR]

The article examines the regulation of symmetric and asymmetric cellular self-renewal and differentiation in the Drosophila embryonic and larval nervous system. It discusses the importance of balance between symmetric and asymmetric stem cell division to tissue generation and repair. Findings show tumorous overgrowth resulting from unregulated stem cell division. Also highlighted is the importance of the Drosophila nervous system model to the biological study of neural stem cell division and tumor formation caused by disruption of molecular mechanisms.

Background The survival advantage of induction chemotherapy (IC) followed by locoregional treatment is controversial in locally advanced head and neck squamous cell carcinoma (LAHNSCC). We previously showed feasibility and safety of cetuximab-based IC (paclitaxel/carboplatin/cetuximab—PCC, and docetaxel/cisplatin/5-fluorouracil/cetuximab—C-TPF) followed by local therapy in LAHNSCC. The primary end point of this phase II clinical trial with randomization to PCC and C-TPF followed by combined local therapy in patients with LAHNSCC stratified by human papillomavirus (HPV) status and T-stage was 2-year progression-free survival (PFS) compared with historical control. Patients and methods Eligible patients were ≥18 years with squamous cell carcinoma of the oropharynx, oral cavity, nasopharynx, hypopharynx, or larynx with measurable stage IV (T0–4N2b–2c/3M0) and known HPV by p16 status. Stratification was by HPV and T-stage into one of the two risk groups: (i) low-risk: HPV-positive and T0–3 or HPV-negative and T0–2; (ii) intermediate/high-risk: HPV-positive and T4 or HPV-negative and T3–4. Patient reported outcomes were carried out. Results A total of 136 patients were randomized in the study, 68 to each arm. With a median follow up of 3.2 years, the 2-year PFS in the PCC arm was 89% in the overall, 96% in the low-risk and 67% in the intermediate/high-risk groups; in the C-TPF arm 2-year PFS was 88% in the overall, 88% in the low-risk and 89% in the intermediate/high-risk groups. Conclusion The observed 2-year PFS of PCC in the low-risk group and of C-TPF in the intermediate/high-risk group showed a 20% improvement compared with the historical control derived from RTOG-0129, therefore reaching the primary end point of the trial. [ABSTRACT FROM AUTHOR]