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This paper presents the details of intermittent ion leakage from a Penning trap during potential barrier closure [H. Himura et al., Phys. Plasmas 24, 102129 (2017)]. A high-energy tail arises in the distribution functions of parallel kinetic energies of the ions after they pass through the upstream potential barrier ϕiu. Correlation between ion leakage and the slew rate of ϕiu is clearly verified. The total number of ions leaking out during the initial leakage is approximately predictable by considering the axial profile of the potential well of the Penning trap. The axial oscillation of leftover ions in the potential well agrees with the (1,0) mode of spheroidal plasmas in Dubin's notation, herein referred to as "Dubin's (1,0) mode," which strongly correlates with the intermittent ion leakage following the initial leakage. [ABSTRACT FROM AUTHOR]

The energy level alignment at interfaces between organic semiconductors is of direct relevance to understand charge carrier generation and recombination in organic electronic devices. Commonly, work function changes observed upon interface formation are interpreted as interface dipoles. In this study, using ultraviolet and X-ray photoelectron spectroscopy, complemented by electrostatic calculations, we find a huge work function decrease of up to 1.4eV at the C60 (bottom layer)/zinc phthalocyanine (ZnPc, top layer) interface prepared on a molybdenum trioxide (MoO3) substrate. However, detailed measurements of the energy level shifts and electrostatic calculations reveal that no interface dipole occurs. Instead, upon ZnPc deposition, a linear electrostatic potential gradient is generated across the C60 layer due to Fermi level pinning of ZnPc on the high work function C60/MoO3 substrate, and associated band-bending within the ZnPc layer. This finding is generally of importance for understanding organic heterojunctions when Fermi level pinning is involved, as induced electrostatic fields alter the energy level alignment significantly. [ABSTRACT FROM AUTHOR]

Intermittent leakages of trapped ions from a Penning trap are clearly explained. Two mechanisms are revealed by considering both experimental and numerical results. The initial leakage is due to ions energized by the potential barrier that is just closing to form a positive potential well. The following leakage is induced by an axial average oscillation of the bulk of the trapped ions. Some individual bounce ions are pushed out of the potential barriers owing to the space potential of the bulk. [ABSTRACT FROM AUTHOR]

Background Gastrointestinal stromal tumor (GIST) is a type of mesenchymal tumor and has KIT mutations in 80–90% of the cases. The development of tyrosine kinase inhibitors have greatly improved patient outcomes. We have previously described association between lower pfetin (KCTD12) expression and poor prognosis in the GIST patients (Ref 1. Suenara Y et al. Clin Cancer Res2008). In this study, to investigate the protein profiles of kit expression, we performed comprehensive protein expression analysis using the gastric tumor cell lines and surgical specimens in GIST. Methods We performed KITgene knockdown using siRNA inthe GIST cell line (T1 cell line) and generated the protein expression profiling data by i-TRAQ. Based on this i-TRAQ protein profiling data from the T1 cell line, we referenced our previously published protein expression analysis databases associated with GIST prognosis in the patient samples (Ref 1.) and compared the protein profile of KIT-associated proteins (T1 cell line) and prognosis-associated protein (patient samples). Results In our study, the i-TRAQ profiling method detected expression of approximately 1500–2000 proteins. In KITknockdown cells, 125 proteins were identified to have statistically different expression (p < 0.05). Based on our previously published GIST prognosis protein profile database (using 17 patient tissue samples), 25 proteins were identified to be statistically significant (p < 0.05). Upon comparing the prognosis database with theKIT knockdown database, 6 proteins were identified as common proteins.In particular, the heat shock protein (HSP) 90-beta, which has been previously shown to contribute to the growth of cancer cells, was identified as a critical protein in the biological behavior of GIST. Conclusions HSP 90-beta is currently considered as a therapeutic target for HSP 90 inhibitors against imatinib-resistant GIST. Our data suggests that the differentiation and cell growth of GIST may be enhanced by the identified proteins, which are in turn induced by KIT. We believe that our established protein profile data will help in improving the understanding of malignant behaviors in GIST. Clinical trial identification HSP 90-betaplay an important role in the tumor progression of GISTs. Legal entity responsible for the study Juntendo University. Funding This study was supported by Grant-in-Aid from the Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Number #19K22694, #19H03789 and #15KK0353 to Y.S. ; #17K08730 to T.S.; #17K10987to K.K.; #19K16753 to K.A.; #18K15329 to T.O. , # 18K16634 to Y.K.) and Leading Advanced Projects for Medical Innovation (LEAP) (Grant Number # JP18am0001009) and the Practical Research for Innovative Cancer Control (Grant Number # JP18ck0106252) from the Japan Agency for Medical Research and Development. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]