13,878 research outputs found
Proton decay in a supersymmetric SO(10) model with missing partner mechanism
The extended supersymmetric SO(10) model with missing partner mechanism is
studied. An intermediate vacuum expectation value is incorporated which
corresponds to the see-saw scale. Gauge coupling unification is not broken
explicitly. Proton decay is found to satisfy the present experimental limits at
the cost of fine-tuning some parameters.Comment: 14 pages; Several improvements, References adde
Connection between proton decay suppression and seesaw mechanism in supersymmetric SO(10) models
We propose a mechanism to suppress proton decay induced by dimension-5
operators in a supersymmetric SO(10) model. Proton lifetime is directly
connected with the intermediate vacuum expectation value which is responsible
for the seesaw mechanism. The model shows many consistencies with the present
theoretical results such as the components of the two Higgs doublets in the
minimal supersymmetric standard model.Comment: 11 pages, no figure. Several minor correction
W-exchange and W-annihilation processes of B mesons
Using the PQCD method we calculate the W-exchange and the W-annihilation
processes of B mesons, which in general involve a charm quark or anti-quark in
the final state. The nonvanishing amplitudes of these processes are found to be
suppressed by a factor of compared to the tree or the time-like
penguin processes, but some of them are within the reach of observation at the
future B-factories, and whose branching ratio is
found to be can be found even before the B-factory era.
Comparisons with the results based on the BSW model are also given.Comment: 11 Pages including figures, accepted in Phys. Lett.
Local Lung Targeting of Tumor Associated Macrophages Combined with Cytoreductive Therapy Decrease Tumor Burden in a Secondary Lung Cancer Model
Backgrounds. The efficacy of a locally administered small molecule colony stimulating factor 1 receptor inhibitor (CSF-1Ri), PLX3397, alone or in combination with cytoreductive therapy (paclitaxel) in reducing the tumor burden of an in vivo model of secondary lung cancer was investigated in this work. Local administration of immunotherapy to the lungs may enhance lung biodistribution of such therapies and reduce potential unwanted off-target toxicity. In addition, combination of such therapy with low dose standard of care chemotherapy may offer improved anti-tumor effects.
Methods. Murine breast cancer cells (4T1, known to be highly metastasized to the lungs) were transduced to express the genes luciferase and tdTomato, and cells were injected to female Balb/c mice before being treated with PLX (intratracheally administered), paclitaxel (intravenously given), or the combination therapy. Both ex vivo bioluminescent imaging and lung weights were used to evaluate tumor burden. Western blot was performed using lung tumors to assess the effect of PLX3397 on its molecular target (phosphorylated CSF-1R). Immunofluorescence and Flowcytometry were utilized to examine the impact of treatment on tumorigenic tumor associated macrophages (M2 TAM).
Results. Single-agent treatment partially decreased tumor burden, while combination therapy led to a significant reduction in tumor burden. PLX3397 significantly inhibited the expression of phosphorylated CSF-1R and reduced the number of M2 TAM without affecting the total macrophage population, thereby increasing the anti-tumorigenic (M1)/M2 ratio.
Conclusion. Tumor burden reduction upon local administration of PLX3397 to the lungs correlates with the marked inhibition of the molecular target and the decrease in M2 TAM.https://scholarscompass.vcu.edu/gradposters/1065/thumbnail.jp
Phase Volume Changes in Multicomponent Extraction Systems Containing Diisopropyl Ether
There are appreciable changes in the phase volumes and the
influence of composition and temperature on these changes is very
pronounced. Benzene was used as the inert diluent and pentyl
alcohol was the active component of the mixed solvent. In all the
above mentioned systems, except systems A and B, the third phase
(heavy organic phase) was observed at room temperature. The addition
of alcohols to some systems suppresses the formation of the
third phase
Compactness and asymptotic behavior in nonautonomous linear parabolic equations with unbounded coefficients in
We consider a class of second order linear nonautonomous parabolic equations
in R^d with time periodic unbounded coefficients. We give sufficient conditions
for the evolution operator G(t,s) be compact in C_b(R^d) for t>s, and describe
the asymptotic behavior of G(t,s)f as t-s goes to infinity in terms of a family
of measures mu_s, s in R, solution of the associated Fokker-Planck equation
Rupture stress of eutectic composite ceramics with rod-shaped crystals
Eutectic composite ceramics has a wide range of applications in the aerospace industry due to its excellent mechanical properties. The rupture stress of the materials is a subject of considerable importance. Eutectic composite ceramics primarily consist of rod-shaped crystals, with a small amount of particles and preexisting defects dispersed throughout. Aligned nano-micron fibers are embedded within the rod-shaped crystals. Rupture stress of a eutectic composite ceramic depends on its fracture surface energy and preexisting defects. In this study, the equivalent fracture surface energy of a eutectic ceramic composite was calculated based on its additional fracture work. Next, the effects of the preexisting defects were considered. Then, a micromechanical model of the eutectic composite ceramic was established based on its microstructural characteristics. The defects were assumed to be lamellar, and the surrounding matrix was assumed to be transversely isotropic. Using this information, the rupture stress of the eutectic ceramic composite was predicted. A comparison of the theoretical and experimental results indicated that the predicted rupture stresses corresponded with the tested data
- …