13 research outputs found
Comprehensive Analyses of the Neutrino-Process in the Core-collapsing Supernova
We investigate the neutrino flavor change effects due to neutrino
self-interaction, shock wave propagation as well as matter effect on the
neutrino process of the core-collapsing supernova. For the hydrodynamics, we
use two models: a simple thermal bomb model and a specified hydrodynamic model
for SN1987A. As a pre-supernova model, we take an updated model adjusted to
explain the SN1987A employing recent development of the reaction
rates for nuclei near the stability line . As for the neutrino
luminosity, we adopt two different models: equivalent neutrino luminosity and
non-equivalent luminosity models. The latter is taken from the synthetic
analyses of the CCSN simulation data which involved quantitatively the results
obtained by various neutrino transport models. Relevant neutrino-induced
reaction rates are calculated by a shell model for light nuclei and a
quasi-particle random phase approximation model for heavy nuclei. For each
model, we present abundances of the light nuclei (Li, Be, B and
C) and heavy nuclei (Nb, Tc, La and Ta)
produced by the neutrino-process. The light nuclei abundances turn out to be
sensitive to the Mikheyev-Smirnov-Wolfenstein region around ONeMg region while
the heavy nuclei are mainly produced prior to the MSW region. Through the
detailed analyses of the numerical abundances, we find that neutrino
self-interaction becomes a key ingredient in addition to the MSW effect for
understanding the neutrino process and the relevant nuclear abundances.
However, the whole results are shown to depend on the adopted neutrino
luminosity scheme. Detailed evaluations of the nuclear abundances for the two
possible neutrino mass hierarchies are performed with the comparison to the
available meteorite analyses data. The normal mass hierarchy is shown to be
more compatible with the meteoritic data
Supernova Nucleosynthesis, Radioactive Nuclear Reactions and Neutrino-Mass Hierarchy
The ν-process nucleosynthesis in core-collapse supernovae is a sensitive probe of unknown neutrino mass hierarchy through the MSW effect. We carefully studied the uncertainties of almost one hundred ν-induced and nuclear reactions associated with the nucleosynthesis and found that the ν-16O and 11C(α,p)14N reactions among them have the biggest effect on the final 7Li/11B isotopic abundance ratio. The neutrino mass hierarchy is constrained in our nucleosynthetic method with measured 7Li/11B value in SiC-X presolar grains. The inverted hierarchy is statistically more favored at the 2-σ C.L. [1]
Thermal properties of flax fiber scoured by different methods
Thermal properties of flax roves untreated and treated were characterized by
differential scanning calorimetry (DSC) and thermal gravity analyzer (TGA)
in order to understand their thermal behavior in more detail and to evaluate
the effect of scouring processing on the thermal behavior. Flax roves were
treated with six kinds of methods including biological scouring, one bath,
two bath, bleaching, alkali scouring and industry chemical scouring as
standards. Results showed that all treatments improved thermal stability of
flax roves. The results indicated that glass transition temperature (Tg)
decreased after scouring besides the sample by directly bleaching. It is
more difficult to determine the endothermic peak of flax treated by chemical
scouring in industry because it takes a very flat course. A distinct
endothermic peak was observed for the untreated flax rove, while a distinct
exothermic peak in different temperature interval was revealed for other
four treated flax rove samples. For TGA analysis, thermal degradation of
flax roves studied consists of three regions of the initial, main, and char
decomposition, and the third stage consists of secondary weight loss and
carbonization for flax roves with biological scouring, one-bath and
two-bath. Besides, different residue left indicates that the bio-scoured
flax roves are lost with volatile products and does not contribute to char
formation. These results provide valuable preferences for mechanism and top
value added application of bio-scouring in flax roves
Recombinant human endostatin endostar suppresses angiogenesis and lymphangiogenesis of malignant pleural effusion in mice.
Malignant pleural effusion (MPE) is a common complication of lung cancer. One widely used treatment for MPE is Endostar, a recombined humanized endostatin based treatment. However, the mechanism of this treatment is still unclear. The aim of this study was to investigate the effects of Endostar in mice with MPE.Lewis lung carcinoma (LLC) cell line expressing enhanced green fluorescent protein (EGFP) was injected into pleural cavity to establish MPE mice model. Mice were randomly divided into four groups. High dose of Endostar (30 mg/kg), low dose of Endostar (8 mg/kg), normal saline, or Bevacizumab (5 mg/kg) was respectively injected into pleural cavity three times with 3-day interval in each group. Transverse computed tomography (CT) was performed to observe pleural fluid formation 14 days after LLC cells injection. Mice were anesthetized and sacrificed 3 days after final administration. The volume of pleural effusion n was measured using 1 ml syringe. Micro blood vessel density (MVD), Lymphatic micro vessel density (LMVD), the expression level of vascular endothelial growth factor A (VEGF-A) and VEGF-C were observed by immunohistochemistry (IHC) staining.The volume of pleural effusion as well as the number of pleural tumor foci, MVD and the expression of VEGF-A were significantly reduced in high dose of Endostar treat group. More importantly, LMVD and the expression of VEGF-C were markedly lower in treat group than those in the other three control groups.Our work demonstrated that Endostar played an efficient anti-cancer role in MPE through its suppressive effect on angiogenesis and lymphangiogenesis, which provided a certain theoretical basis for the effectiveness of Endostar on the MPE treatment
Immunohistochemistry staining of VEGF-C expression in the pleural tumors.
<p>Positive immunohistochemistry staining of VEGF-C was shown as brown part in each figure. Expression of VEGF-C was accessed by the percentage of positive carcinoma cells and the staining intensity. The positive staining of VEGF-C in NS group (A) and L-ES group (B) indicated high expression of VEGF-C in these groups. Low expression of VEGF-C was shown in Bevacizumab group (C) and H-ES group (D). The expression of VEGF-C was significantly decreased in H-ES group compared with that in NS group or L-ES group or Bevacizumab group.Columns: mean value of each group, bars: ±SD. ***P<0.001, **P<0.01, *P<0.05. ns: no significant difference.</p
Histology of pleural tumors and cytology of MPE from the mice in NS group.
<p>(A) Hematoxylin-eosin staining of parietal pleura from MPE model (Section ×200) indicated that pleural tumors consisted of adenocarcinomatous cells. (B) Hematoxylin-eosin staining of tumor on the pleural surface from MPE model (Section ×200). (C) Wright’s-Giemsa stain of cells from pleural effusion of MPE model showed LLC cells with large nuclei and visible nucleoli (arrow). MPE: malignant pleural effusion.</p
CT scanning of MPE formation in four groups.
<p>CT images of four groups showed that bilateral pleural effusion was visible in the mice treated with NS (A) or L-ES (B),unilateral pleural effusion was observed in Bevacizumab group (C), and effusion was not obvious in H-ES group (D). The mean volume of pleural effusion was significantly decreased in the H-ES group compared with that in the NS group or L-ES group, but there is no significant difference between H-ES group and Bevacizumab group (E). MPE: malignant pleural effusion. Columns: mean value of each group, bars: ±SD. ***P<0.001, **P<0.01, *P<0.05. ns: no significant difference.</p
Immunohistochemistry staining of VEGF-A expression in the pleural tumors.
<p>Positive immunohistochemistry staining of VEGF-A was shown as brown part in each figure. Expression of VEGF-A was accessed by the percentage of positive carcinoma cells and the staining intensity. The positive staining of VEGF-A in NS group (A) and L-ES group (B) indicated high expression of VEGF-A in these groups. Low expression of VEGF-A was shown in Bevacizumab group (C) and H-ES group (D). The expression of VEGF-A was significantly decreased in H-ES group compared with that in NS group or L-ES group, and there is no significant difference between Bevacizumab group and H-ES group (E). Columns: mean value of each group, bars: ±SD. ***P<0.001, **P<0.01, *P<0.05. ns: no significant difference.</p
Immunohistochemistry staining of D2-40 for LMVD in the pleural tumors.
<p>Positive immunohistochemistry staining of D2-40 was shown as brown part in each figure. Positive endothelial cells stained by anti-D2-40 antibody were recognized as lymphatic vessels. Lymphatic micro vessel density (LMVD) was counted at Section×200. LMVD in H-ES group (D) was significantly decreased compared with NS group (A) or L-ES group (B) or Bevacizumab group(C). (E): The difference of LMVD on four groups. Columns: mean value of each group, bars: ±SD. ***P<0.001, **P<0.01, *P<0.05. ns: no significant difference.</p