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Dissociative charge exchange reactions between Ar+ ion and trans- /cis- dichloroethylene (trans-/cis-C2H2Cl2) are investigated with the ion-velocity imaging technique. The dechlorinated product C2H2Cl+ is the predominant, and most of this product show the spatial distribution around the target, implying that the dissociation occurs in the large impact-parameter collision and via the energy resonant charge transfer. Meanwhile, a few C2H2Cl+ locate around the center-of-mass, which is attributed to the fragmentation of intimate association between C2H2Cl2 and Ar+ or in the small impact-parameter collision. The product C2HCl+ exhibits the velocity distribution features similar to those of C2H2Cl+. The rarest product C2HCl2+ shows the distributions around the molecular target, due to the quick dehydrogenation after the energy-resonant charge transfer in the large impact-parameter collision. [ABSTRACT FROM AUTHOR]

Molecular electronic or vibrational states can be superimposed temporarily in an extremely short laser pulse, and the superposition-state transients formed therein receive much attention, owing to the extensive interest in molecular fundamentals and the potential applications in quantum information processing. Using the crossed-beam ion velocity map imaging technique, we disentangle two distinctly different pathways leading to the forward-scattered N2+ yields in the large impact-parameter charge transfer from low-energy Ar+ to N2. Besides the ground-state (X2Σg+) N2+ produced in the energy-resonant charge transfer, a few slower N2+ ions are proposed to be in the superpositions of the X2Σg+-A2Πu and A2Πu-B2Σu+ states on the basis of the accidental degeneracy or energetic closeness of the vibrational states around the X2Σg+-A2Πu and A2Πu-B2Σu+ crossings in the non-Franck–Condon region. This finding potentially shows a brand-new way to prepare the superposition-state molecular ion. [ABSTRACT FROM AUTHOR]

Aims Interleukin (IL)-5 mediates the development of eosinophils (EOS) that are essential for tissue post-injury repair. It remains unknown whether IL-5 plays a role in heart repair after myocardial infarction (MI). This study aims to test whether IL-5-induced EOS population promotes the healing and repair process post-MI and to reveal the underlying mechanisms. Methods and results MI was induced by permanent ligation of the left anterior descending coronary artery in wild-type C57BL/6 mice. Western blot and real-time polymerase chain reaction revealed elevated expression of IL-5 in the heart at 5 days post-MI. Immunohistostaining indicated that IL-5 was secreted mainly from macrophages and CD127+ cells in the setting of experimental MI. External supply of recombinant mouse IL-5 (20 min, 1 day, and 2 days after MI surgery) reduced the infarct size and increased ejection fraction and angiogenesis in the border zone. A significant expansion of EOS was detected in both the peripheral blood and infarcted myocardium after IL-5 administration. Pharmacological depletion of EOS by TRFK5 pretreatment muted the beneficial effects of IL-5 in MI mice. Mechanistic studies demonstrated that IL-5 increased the accumulation of CD206+ macrophages in infarcted myocardium at 7 days post-MI. In vitro co-culture experiments showed that EOS shifted bone marrow-derived macrophage polarization towards the CD206+ phenotypes. This activity of EOS was abolished by IL-4 neutralizing antibody, but not IL-10 or IL-13 neutralization. Western blot analyses demonstrated that EOS promoted the macrophage downstream signal transducer and activator of transcription 6 (STAT6) phosphorylation. Conclusion IL-5 facilitates the recovery of cardiac dysfunction post-MI by promoting EOS accumulation and subsequent CD206+ macrophage polarization via the IL-4/STAT6 axis. [ABSTRACT FROM AUTHOR]

Charge exchange reactions between Ar+(2P) and O2 (X3Σ −g) are investigated in the collision energy range of 3.40–9.24 eV within the center-of-mass coordinate, by using the ion momentum imaging technique. The internal energy of the product O2+ is enhanced gradually with the increase of collision energy, and the forward-scattered O2+ ions are distributed in the broader range of scattering angle at higher collision energies. At the low collision energy of 3.40 eV, the resonant charge transfer, similar to a photon ionization process, leads to the Franck–Condon-like vibrational state population of O2+ at the a4Πu state. At the higher collision energies, besides a4Πu and the high-lying states that are visible in the photoionization process, the O2+ products could be populated at some electronically bound states in the non-Franck–Condon region. The present observations indicate again the strong collision-energy dependences of the charge exchange reactions, but distinctly different from our previous findings for Ar+ + NO → Ar + NO+. [ABSTRACT FROM AUTHOR]

Background: To provide a comprehensive overview of temporal trends in cancer incidence during 1973-2010 in urban Shanghai.Methods: The estimated annual percent changes (EAPCs) for the whole period and for the time segments in age-standardized incidence rates (ASR) were evaluated with Joinpoint analysis. Age-period-cohort (APC) models were modeled to examine the effects of age, period and birth cohort on cancer incidence.Results: The overall ASR decreased slightly and significantly in males (EAPC of -0.41) but increased significantly in females (EAPC of 0.57) during 1973-2010 in urban Shanghai. The incidence trend was not linear and varied by time segments. During the most recent 10 years (2001-2010), the ASR in males decreased by 1.65% per year and stabilized in females. Incidence rates continued to decline during 1973-2010 for esophagus, stomach, and liver cancer in both sexes, as well as male lung cancer and cervix cancer. It should be noted that it was the first time to document a significant decline in lung cancer incidence among males during 1973-2010 with EAPC of -0.58%, and a notable upward for cervix cancer since 1996 with EAPC of 8.94%. Unfavorable trends in incidence were observed for the most common cancer sites in the 38 years period: colorectum, gallbladder & biliary tract, pancreas, kidney, bladder, brain & central nervous system (CNS), thyroid, non-Hodgkin's lymphoma (NHL), prostate, female breast, corpus uteri, and ovary. APC analysis showed age, period and birth cohort yielded different effects by cancer sites.Conclusions: The observed trends primarily reflect dramatic changes in socioeconomic development and lifestyles in urban Shanghai over the past four decades. [ABSTRACT FROM AUTHOR]

Here we report a pulsed low-energy ion beam source for ion-molecule reaction study, in which the ions produced by the pulsed electron impact are confined well in the spatial size of each bunch. In contrast to the ion focusing method to reduce the transverse section of the beam, the longitudinal section in the translational direction is compressed by introducing a second pulse in the ion time-of-flight system. The test experiments for the low-energy argon ions are performed. The present beam source is ready for applications in the ion-molecule reaction dynamics experiments, in particular, in combination with the ion velocity map imaging technique. [ABSTRACT FROM AUTHOR]

Here we report a pulsed low-energy ion beam source for ion-molecule reaction study, in which the ions produced by the pulsed electron impact are confined well in the spatial size of each bunch. In contrast to the ion focusing method to reduce the transverse section of the beam, the longitudinal section in the translational direction is compressed by introducing a second pulse in the ion time-of-flight system. The test experiments for the low-energy argon ions are performed. The present beam source is ready for applications in the ion-molecule reaction dynamics experiments, in particular, in combination with the ion velocity map imaging technique. [ABSTRACT FROM AUTHOR]