Signals of powerful ground transmitters at various places have been detected by satellites in near‐Earth space. The study on propagation mode, ducted or nonducted, has attracted much attentions for several decades. Based on the statistical results from Van Allen Probes (data from October 2012 to March 2017) and DEMETER satellite (from January 2006 to December 2007), we present the ground transmitter signals distributed clearly in ionosphere and magnetosphere. The observed propagation route in the meridian plane in the magnetosphere for each of various transmitters from the combination of DEMETER and Van Allen Probes data in nighttime is revealed for the first time. We use realistic ray tracing simulation and compare simulation results against Van Allen Probes and DEMETER observation. By comparison we demonstrate that the observed propagation route, with partial deviation from the field lines corresponding to ground stations, provides direct and clear statistical evidence that the nonducted propagation mode plays a main role, although with partial contribution from ducted propagation. The propagation characteristics of VLF transmitter signals in the magnetosphere are critical for quantitatively assessing their contribution to energetic electron loss in radiation belts.
An enhancement near threshold is observed in the omega(phi) invariant mass spectrum from the doubly Okubo-Zweig-Iizuka-suppressed decays of J/psi-->gamma(omega)phi, based on a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A partial wave analysis shows that this enhancement favors JP=0+, and its mass and width are M=1812(+19)(-26)(stat)+/-18(syst) MeV/c2 and Gamma=105+/-20(stat)+/-28(syst) MeV/c2. The product branching fraction is determined to be B(J/psi-->gammaX)B(X-->omega(phi))=[2.61+/-0.27(stat)+/-0.65(syst)]x10(-4).
Lymphatic metastasis has always been regarded as a major prognostic indicator for disease progression and as a guide for therapeutic strategies to oral squamous cell carcinoma (OSCC), but to date, how tumor cells access and spread via the lymphatics have not been fully elucidated. Whether tumor cells metastasize by expansion and invasion of pre-existing peritumoral lymphatics or by the induction and invasion of newly formed lymphatics within tumors is controversial. In order to address this issue and find out the clinicopathological significance of intratumoral lymphangiogenesis, we investigated 86 archival specimens from patients with OSCC, quantitating lymph vessels by immunostaining with D2-40. We also quantified lymphatic invasion and examined the possible associations of all the above parameters with clinicopathological features and outcome. Higher intratumoral lymphatic density (ILD) and peritumoral lymphatic density (PLD) were both significantly associated with the presence of lymph node metastasis at the time of diagnosis and the outcome of the post-operation biopsy of 77 patients (P = 0.001). Higher ILD was significantly associated with a higher incidence of intratumoral lymphatic invasion, peritumoral lymphatic invasion and recurrence of tumor (P = 0.001 and P = 0.041 and P = 0.001, respectively). Patients with higher ILD exhibited shorter 5-year cumulative and disease-free survival (P = 0.001). Thus, lymphangiogenesis indeed occurs in oral squamous cell carcinoma; ILD might be used as an index to inflect the aggression of the disease, to evaluate the status of lymphatic metastasis, to separate patients at higher risk of an adverse clinical outcome.
[1] We analyzed observation data collected by the Instrument for the Detection of Particles (IDP) on board the DEMETER satellite during a period of 17 months in 2007 and 2008. In the meantime, the VLF transmitter located at North West Cape (NWC) ground station was shut down during 7 months and working for a total of 10 months. By an (on-off) method, our analysis for the first time revealed in detail the transient properties of the space electron precipitation belt which is induced by the man-made VLF wave emitted from NWC. We mapped the electron flux distribution and figured out the space regions that the NWC belt covered. The NWC electron spectrograms have been investigated in a wide range of the McIlwain parameter L (1.1-3.0). Furthermore, we obtained the averaged energy spectra of the NWC electrons within the drift loss cone and compared their characteristics during daytime and nighttime. Our results confirm the previous studies of the enhancement of NWC electrons, the wisp structure, and the day/night difference of the electron flux. In addition, more detailed information is provided. We provide not only evidence of a momentary flux enhancement up to 3 orders of magnitude but also a flux reduction at higher L shells with a maximum up to 60% of the original value. For the first time, the energy spectra of NWC electrons covering the entire IDP energy band are presented for both nighttime and daytime and are quantitatively compared. At the end, our results are discussed, and their agreement with the theory of wave-particle interactions is checked.
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