1,386 research outputs found
Development and investigation of implantable tablets for wound healing modulation after trabeculectomy
Modulation of wound healing is required to inhibit scar formation after trabeculectomy. Mitomycin C and 5-fluorouracil (5-FU) are the anti-proliferative drugs currently used in the clinic. Their effectiveness is limited due to their toxicity and suboptimal local tissue pharmacokinetics caused by rapid clearance within the subconjunctival space. Therefore, prolonged release of anti-scarring agents is needed. Ilomastat is a matrix metalloproteinase inhibitor that has been shown to moderate favorably the wound healing response after surgery. However, due to rapid local tissue clearance, several injections are necessary in a clinically relevant animal model.
The thesis describes the development and investigation of implantable ocular tablets for wound healing modulation after trabeculectomy. A tablet would be placed in the subconjunctival space called a bleb, which is caused by the outflow through the fistula made during surgery. While the bleb volume varies, the tablet is thought to dissolve in non-sink conditions. Tablet dissolution was evaluated in vitro using a flow chamber that mimics the liquid outflow conditions of the bleb. The in vitro release studies suggest that tablet dissolution would act to prolong drug release in comparison with injections. Tablet dissolution in the subconjunctival space is affected by many factors including the physical/chemical properties of the drug and tablet, temperature, the volume and flow rate of the dissolution media, and the surface area of the tablet. The efficacy of an excipient-free ilomastat tablet was evaluated using a clinically validated rabbit model. The tablet dissolution was examined using molecular dynamics simulations to consider the molecular interactions of ilomastat and 5-FU undergoing dissolution in non-sink conditions. A mathematical model was also developed to describe the dissolution of excipient-free tablets in the non-sink conditions with 94% confidence. In conclusion, we have established methods to investigate and simulate dissolution of excipientless tablets in non-sink conditions within the subconjunctival space
The Friedmann equation in modified entropy-area relation from entropy force
According to the formal holographic principle, a modification to the
assumption of holographic principle in Verlinder's investigation of entropy
force is obtained. A more precise relation between entropy and area in the
holographic system is proposed. With the entropy corrections to the
area-relation, we derivate Newton's laws and Einstein equation with a static
spherically symmetric holographic screen. Furthermore we derived the correction
terms to the modified Friedmann equation of the FRW universe starting from the
holographic principle and the Debye model.Comment: Mod. Phys. Lett. A26, 489-500 (2011
Quark deconfinement phase transition for improved quark mass density-dependent model
By using the finite temperature quantum field theory, we calculate the finite
temperature effective potential and extend the improved quark mass
density-dependent model to finite temperature. It is shown that this model can
not only describe the saturation properties of nuclear matter, but also explain
the quark deconfinement phase transition successfully. The critical temperature
is given and the effect of - meson is addressed.Comment: 18 pages, 7 figure
An analysis of the X-ray emission from the supernova remnant 3C397
The ASCA SIS and the ROSAT PSPC spectral data of the SNR 3C397 are analysed
with a two-component non-equilibrium ionization model. Besides, the ASCA SIS0
and SIS1 spectra are also fitted simultaneously in an equilibrium case. The
resulting values of the hydrogen column density yield a distance of \sim8\kpc
to 3C397. It is found that the hard X-ray emission, containing S and Fe
K lines, arises primarily from the hot component, while most of the
soft emission, composed mainly of Mg, Si, Fe L lines, and continuum, is
produced by the cool component. The emission measures suggest that the remnant
evolves in a cloudy medium and imply that the supernova progenitor might not be
a massive early-type star. The cool component is approaching ionization
equilibrium. The ages estimated from the ionization parameters and dynamics are
all much greater than the previous determination. We restore the X-ray maps
using the ASCA SIS data and compare them with the ROSAT HRI and the NRAO VLA
Sky Survey (NVSS) 20 cm maps. The morphology with two bright concentrations
suggests a bipolar remnant encountering a denser medium in the west.Comment: 20 pages, aasms4.sty, 3 figures To appear in ApJ (1999
Exraction and separation of CERIUM(IV)/FLUORINE in fluoride-bearing cerium sulfate solution with fluoride coordination agent
In this paper the extraction and separation of cerium/fluorine in fluoride-bearing cerium sulfate solution with fluoride coordination agent has been studied. The UV-vis spectra suggest that Zr6+ and Al3+ can scrub the F- from [CeF2] 2+ complex. The separation and conductivity studies show that aluminum salt is the most suitable fluoride coordination agent, and an ion-exchange reaction is involved between Ce4+/ [CeF2] 2+ and hydrogen ion
Exraction and separation of CERIUM(IV)/FLUORINE in fluoride-bearing cerium sulfate solution with fluoride coordination agent
In this paper the extraction and separation of cerium/fluorine in fluoride-bearing cerium sulfate solution with fluoride coordination agent has been studied. The UV-vis spectra suggest that Zr6+ and Al3+ can scrub the F- from [CeF2] 2+ complex. The separation and conductivity studies show that aluminum salt is the most suitable fluoride coordination agent, and an ion-exchange reaction is involved between Ce4+/ [CeF2] 2+ and hydrogen ion
Removal of fluoride from fluoride-bering cerium sulfate solution by hydrous zirconium oxide
In this paper the removal of fluoride from fluoride-bearing cerium sulfate solution by amorphous hydrous zirconium oxide was studied. The FTIR, SEM, EDS and UV-vis spectra show that fluoride is successfully adsorbed on hydrous zirconium oxide, and cerium exists as Ce4+ in solution. The study indicates that it is feasible to separate fluorine and cerium from fluorine-bearing rare earth sulfate solution using hydrous zirconium oxide, and eliminate the influence of fluoride on the extraction separation of rare earths
Testing the viability of the interacting holographic dark energy model by using combined observational constraints
Using the data coming from the new 182 Gold type Ia supernova samples, the
shift parameter of the Cosmic Microwave Background given by the three-year
Wilkinson Microwave Anisotropy Probe observations, and the baryon acoustic
oscillation measurement from the Sloan Digital Sky Survey, and lookback
time measurements, we have performed a statistical joint analysis of the
interacting holographic dark energy model. Consistent parameter estimations
show us that the interacting holographic dark energy model is a viable
candidate to explain the observed acceleration of our universe.Comment: 15 pages, 9 figures, accepted for publication in JCA
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