36 research outputs found

    Measurement of the Atmospheric Muon Spectrum from 20 to 3000 GeV

    Get PDF
    The absolute muon flux between 20 GeV and 3000 GeV is measured with the L3 magnetic muon spectrometer for zenith angles ranging from 0 degree to 58 degree. Due to the large exposure of about 150 m2 sr d, and the excellent momentum resolution of the L3 muon chambers, a precision of 2.3 % at 150 GeV in the vertical direction is achieved. The ratio of positive to negative muons is studied between 20 GeV and 500 GeV, and the average vertical muon charge ratio is found to be 1.285 +- 0.003 (stat.) +- 0.019 (syst.).Comment: Total 32 pages, 9Figure

    Seasonal dynamics in cambial activity and the formation of xylem and phloem in the branches of Cinnamomum camphora

    No full text
    The cambial activity and periodicity of secondary xylem and phloem formation have been less studied in tropical tree species than in temperate ones. Cambium activity is the only source of timber production. Studies on its activity and xylem formation can provide helpful data for dendrochronology and possible factors that control tree growth, the yield and quality of wood. Cinnamomum camphora is an important fast-growing tree for furniture and sculpture wood in South China. Its dynamics of cambial activity was not reported. During the growth season in 2011, five trees of Cinnamomum camphora plantation were monitored on the campus of Huazhong Agricultural University in central china (located on 113°41’ to 115°05’ E and 29°58’ to 31°22’ N). Sampling time was from 13, February 2011 to 13, February 2012. Some small stems of 15–20 cm length were selected to sample in the middle of 2–3 years old health branches in the central crown of these trees. The observational study found that the cambium of camphor trees was active from March to October and dormant from November to February. Onset of cambial cell division was observed in early March, one week after sprouting of new buds. The morphology of the cells and number of cell layers in the cambium zone varied throughout the year. In early March, cambium reactivated with the rising of temperature, the cell wall was relative thick. The number of cell layers increased from 2–3 in middle Feb. to 3–5. In June, the number of cell layers in cambium reached the maximum of 5–7 in a radial direction. In mid March, phloem cells began to differentiate, followed by xylem three weeks later. The number of cell layers in immature phloem and xylem increased dramatically before mid June and the increment of cell layers in xylem was almost fifth times of phloem in the differentiating process. The phloem cells mainly stopped dividing new cells in end of October, but xylem cells were still in the activity a week later. The annual activities of cambium was in accordance with the air mean temperature change in 2011–2012. The results showed that the cambial activity and formation of xylem and phloem were related to the environmental factors, especially the temperature

    Biological mechanism of post-herpetic neuralgia: Evidence from multiple patho-psychophysiological measures

    No full text
    BackgroundPost-herpetic neuralgia (PHN), which develops after the resolution of a herpes zoster eruption, is an exceptionally drug-resistant neuropathic pain. The unsatisfactory management of PHN partly results from the difficulty in dissecting out its contributing factors due to the complexity of PHN mechanism.&nbsp; MethodsHere, to elaborate our understanding of the PHN mechanism and to establish a basis for effective therapeutic strategies, we comprehensively investigated the contributions of multiple factors to PHN severity.&nbsp; ResultsBased on the comparison of somatosensory detection thresholds (C, A and A fibre thresholds) between affected and unaffected sides, 16 PHN patients with significant sensory deficits and 13 PHN patients without significant sensory deficits were identified and assigned to different groups. The different extents of lesions in the nociceptive system between patients with and without sensory deficits were confirmed using laser-evoked brain responses. Moreover, patients with sensory deficits had more severe pain and psychological disorders, e.g. anxiety and depression. Importantly, chronic pain severity was significantly influenced by various psychophysiological factors (sleep disturbances, psychological disorders and hypothalamic-pituitary-adrenal axis dysfunction) for patients with sensory deficits.&nbsp; ConclusionsOur findings demonstrated the contribution of multiple patho-psychophysiological factors to PHN severity, which could help establish a basis for the development of a rational, patient-centred therapeutic strategy.&nbsp; SignificanceThis study revealed the contribution of multiple patho-psychophysiological factors to PHN severity, which expanded our understanding of the underlying PHN mechanism, and helped develop a rational, patient-centred therapeutic strategy targeting towards the corresponding etiology and psychophysiological disorders for individual patient.</p

    Observation of possible topological in gap surface states in the Kondo insulator SmB6 by photoemission

    Get PDF
    SmB(6), a well-known Kondo insulator, exhibits a transport anomaly at low temperature. This anomaly is usually attributed to states within the hybridization gap. Recent theoretical work and transport measurements suggest that these in-gap states could be ascribed to topological surface states, which would make SmB(6) the first realization of topological Kondo insulator. Here by performing angle-resolved photoemission spectroscopy experiments, we directly observe several dispersive states within the hybridization gap of SmB(6). These states show negligible k(z) dependence, which indicates their surface origin. Furthermore, we perform photoemission circular dichroism experiments, which suggest that the in-gap states possess chirality of the orbital angular momentum. These states vanish simultaneously with the hybridization gap at around 150 K. Together, these observations suggest the possible topological origin of the in-gap states

    KEAP1 E3 Ligase-Mediated Downregulation of NF-kappa B Signaling by Targeting IKK beta

    No full text
    I kappa B kinase beta (IKK beta) is involved in tumor development and progression through activation of the nuclear factor (NF)-kappa B pathway. However, the molecular mechanism that regulates IKK beta degradation remains largely unknown. Here, we show that a Cullin 3 (CUL3)-based ubiquitin ligase, Kelch-like ECH-associated protein 1 (KEAP1), is responsible for IKK beta ubiquitination. Depletion of KEAP1 led to the accumulation and stabilization of IKK beta and to upregulation of NF-kappa B-derived tumor angiogenic factors. A systematic analysis of the CUL3, KEAP1, and RBX1 genomic loci revealed a high percentage of genome loss and missense mutations in human cancers that failed to facilitate IKK beta degradation. Our results suggest that the dysregulation of KEAP1-mediated IKK beta ubiquitination may contribute to tumorigenesis
    corecore