2,711 research outputs found
A Temperature-Precipitation Based Leafing Model and Its Application in Northeast China
Plant phenology models, especially leafing models, play critical roles in evaluating the impact of climate change on the primary production of temperate plants. Existing models based on temperature alone could not accurately simulate plant leafing in arid and semi-arid regions. The objective of the present study was to test the suitability of the existing temperature-based leafing models in arid and semi-arid regions, and to develop a temperature-precipitation based leafing model (TP), based on the long-term (i.e., 12–27 years) ground leafing observation data and meteorological data in Northeast China. The better simulation of leafing for all the plant species in Northeast China was given by TP with the fixed starting date (TPn) than with the parameterized starting date (TPm), which gave the smallest average root mean square error (RMSE) of 4.21 days. Tree leafing models were validated with independent data, and the coefficient of determination (R2) was greater than 0.60 in 75% of the estimates by TP and the spring warming model (SW) with the fixed starting date. The average RMSE of herb leafing simulated by TPn was 5.03 days, much lower than other models (>9.51 days), while the average R2 of TPn and TPm were 0.68 and 0.57, respectively, much higher than the other models (<0.22). It indicates that TPn is a universal model and more suitable for simulating leafing of trees and herbs than the prior models. Furthermore, water is an important factor determining herb leafing in arid and semi-arid temperate regions
Phenomenological study of decays
The measurement of decay parameters is one of the important goals of particle
physics experiments, and the measurement serves as a probe to search for
evidence of CP violation in baryonic decays. The experimental results will help
advance existing theoretical research and establish new experimental
objectives. In this paper, we formulate the asymmetric parameters that
characterize parity violation, and then derive formulas for the measurement of
CP violation. The formulae for the joint angular distribution of the full decay
chain as well as the polarization observable of , , and are also provided for experiments.
Lastly, we evaluated the sensitivity of two asymmetric parameters: (abbreviated as ) and
(abbreviated as
) for future experimental measurement.Comment: 8 pages, 5 figure
The emerging role of cellular senescence in renal diseases
Cellular senescence represents the state of irreversible cell cycle arrest during cell division. Cellular senescence not only plays a role in diverse biological events such as embryogenesis, tissue regeneration and repair, ageing and tumour occurrence prevention, but it is also involved in many cardiovascular, renal and liver diseases through the senescence-associated secretory phenotype (SASP). This review summarizes the molecular mechanisms underlying cellular senescence and its possible effects on a variety of renal diseases. We will also discuss the therapeutic approaches based on the regulation of senescent and SASP blockade, which is considered as a promising strategy for the management of renal diseases
Productions of X(1835) as baryonium with sizable gluon content
The X(1835) has been treated as a baryonium with sizable gluon content, and
to be almost flavor singlet. This picture allows us to rationally understand
X(1835) production in radiative decays, and its large couplings with
, . The processes and have been examined. It has been found
that , which is compatible with CLEO's recently
experimental result (Phys.Rev. (2006) 032001;hep-ex/0510015). The
branching fractions of , with and
have been estimated by the quark-pair
creation model. We show that they are heavily suppressed, so the signal of
X(1835) is very difficult, if not impossible, to be observed in these
processes. The experimental checks for these estimations are expected. The
existence of the baryonium nonet is conjectured, and a model independent
derivation of their production branching fractions is presented.Comment: 21 pages, 4 figure
Preliminary study on the immunology pathogenesis of ocular myasthenia gravis in children
AIM: To discuss the role of humoral immunity and cellular immunity in the development of ocular myasthenia gravis in children by analyzing the clinical value of the indices including immunoglobulin, complement and T cell subgroup in peripheral blood. <p>METHODS: The concentrations of serum IgG, IgA, IgM, C3 and C4 in the myasthenia gravis group and the control group were detected by immune compare turbid. The contents of CD3<sup>+</sup>T cell, CD4<sup>+</sup>T cell and CD8<sup>+</sup>T cell were detected by flow cytometry. Data was analyzed by Independent-Sample Test.<p>RESULTS: There were no significant differences in contents of IgA, IgM, CD3<sup>+</sup>T cell, CD8<sup>+</sup>T cell between ocular myasthenia gravis group in children and the control group(<i>P</i>>0.05). The concentrations of serum IgG, C3 and C4 for myasthenia gravis group were lower than those of the control group(<i>P</i><0.05). The content of CD4<sup>+</sup>T cell were higher than those of the control group(<i>P</i><0.05).<p>CONCLUSION: Complement C3, C4 and CD4<sup>+</sup>T cell played an important role in immunology pathogenesis mechanism for ocular myasthenia gravis in children
Dynamical study of the light scalar mesons below 1 GeV in a flux-tube model
The light scalar mesons below 1 GeV as tetraquark states are studied in the
framework of the flux-tube model, the multi-body confinement instead of the
additive two-body confinement is used. From the calculated results, we find
that the light scalar mesons, , could be well accommodated in
the diquark-antidiquark tetraquark picture in the flux-tube model and they
could be color confinement resonances. The mass of the first radial excited
state of is 1019 MeV, which is close to the mass of
. Whereas can not be fitted in this interpretation.Comment: 11 pages, 1 figur
- …