576 research outputs found
6-Formyl-2-naphthyl cis-1,5,7-trimethyl-2,4-dioxo-3-azabicyclo[3.3.1]nonane-7-carboxylate
In the title compound, C23H23NO5, the C5N ring adopts an envelope conformation with a C atom as the flap, whilst the saturated C6 ring fused to it adopts a chair conformation. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate R
2
2(8) loops
Fuzzy PID control of a two-link flexible manipulator
For a flexible manipulator system, the unwanted vibrations deteriorate usually the performance of the system due to the coupling of large overall motion and elastic vibration. This paper focuses on the active vibration control of a two-link flexible manipulator with piezoelectric materials. The multi flexible body dynamics (MFBD) model of the two-link flexible manipulator attached with piezoelectric sensors and actuators is established firstly. Based on the absolute nodal coordinate formulation (ANCF), the motion equations of the manipulator system are derived and motion process and dynamic responses of the system are simulated. According to the time varying feature of system, a fuzzy PID controller is developed to depress the vibration. This controller can tune control gains online accommodating to the variation of the system. Control results obtained by the fuzzy PID control and the conventional PID control indicate that the fuzzy PID controller can effectively suppress the elastic vibration of the manipulator system and performs better than the conventional PID controller
Ionic effect on combing of single DNA molecules and observation of their force-induced melting by fluorescence microscopy
Molecular combing is a powerful and simple method for aligning DNA molecules
onto a surface. Using this technique combined with fluorescence microscopy, we
observed that the length of lambda-DNA molecules was extended to about 1.6
times their contour length (unextended length, 16.2 micrometers) by the combing
method on hydrophobic polymethylmetacrylate (PMMA) coated surfaces. The effects
of sodium and magnesium ions and pH of the DNA solution were investigated.
Interestingly, we observed force-induced melting of single DNA molecules.Comment: 12 page
Higgs boson decays to meson in the fragmentation-function approach
In the paper, we present a calculation of the decay widths for the Higgs
boson decays to the , , and mesons
using the fragmentation-function approach. In the calculation, the
fragmentation functions up to order based on the nonrelativistic
QCD factorization theory are used, and the decay widths for and at the partonic level are calculated up to order . The large
logarithms of are resummed up to next-to-leading logarithmic
accuracy by solving the evolution equations for the running quark masses and
the fragmentation functions. Compared to the leading-order decay widths based
on the nonrelativistic QCD approach, the decay widths based on the
fragmentation-function approach that include the higher-order QCD corrections
are reduced significantly. Our numerical results show that there are about
events via the Higgs decays to be produced at the HL-LHC
with , and about events via the Higgs decays
to be produced at the HE-LHC with .Comment: 12 pages, 9 figure
Immune Responses Following Mouse Peripheral Nerve Xenotransplantation in Rats
Xenotransplantation offers a potentially unlimited source for tissues and organs for transplantation, but the strong xenoimmune responses pose a major obstacle to its application in the clinic. In this study, we investigate the rejection of mouse peripheral nerve xenografts in rats. Severe intragraft mononuclear cell infiltration, graft distension, and necrosis were detected in the recipients as early as 2 weeks after mouse nerve xenotransplantation. The number of axons in xenografts reduced progressively and became almost undetectable at week 8. However, mouse nerve xenotransplantation only led to a transient and moderate increase in the production of Th1 cytokines, including IL-2, IFN-γ, and TNF-α. The data implicate that cellular immune responses play a critical role in nerve xenograft rejection but that further identification of the major effector cells mediating the rejection is required for developing effective means to prevent peripheral nerve xenograft rejection
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