Parameter-Independent Symmetries in Nuclear Structure

The E(5) symmetry describes nuclei related to the U(5)--SO(6) phase transition, while the X(5) symmetry is related to the U(5)--SU(3) phase transition. A chain of potentials interpolating between the U(5) symmetry of the 5-dimensional harmonic oscillator and the E(5) symmetry is considered. Parameter independent predictions for the spectra and B(E2) values of nuclei with $R_4= E(4)/E(2)$ ratios 2.093, 2.135, and 2.157 (compared to the ratio 2.00 of the U(5) case and the ratio 2.20 of the E(5) case) are derived numerically and compared to existing experimental data, suggesting several new experiments. Furthermore, an exactly soluble model with $R_4 = 2.646$ is constructed and a chain of potentials interpolating between this new model and the X(5) symmetry is considered. Parameter independent predictions for the spectra and B(E2) values of nuclei with $R_4$ ratios 2.769, 2.824 and 2.852 (compared to the ratio 2.904 of the X(5) case) are derived numerically and compared to existing experimental data, suggesting several new experiments.

EFFECT OF CROSSLINKER AMOUNT ON HYBRID HYDROGELS SWELLING AND DRUG RELEASE

Targeted drug delivery is powerful tool which researchers use to achieve safer and more efficient therapy of many diseases, including various types of cancer. Many chemotherapeutics are poorly water- soluble, so their encapsulation and targeted delivery remain quite challenge. Hydrogels based on poly(methacrylic acid) (PMAA) are widely investigated for targeted drug delivery due to their pH sensitivity, non-toxicity and biocompatibility. Still, due to the PMAA highly hydrophilic nature, PMAA can only be used for encapsulation and targeted delivery of water-soluble drugs. Our previous research was directed towards overcoming this limitation: PMAA was modified with amphiphilic protein – casein and poorly-water soluble model drug – caffeine – was encapsulated (PMAC). Present study is focused on investigation how variation of amount of one of the most important hydrogels network parameter such as crosslinker affect PMAC swelling properties and caffeine release. The group of hybrid hydrogels – PMAC – was synthesized with various amount of crosslinker: 0.4mol%, 0.8mol%, 1.6mol% and 3.2mol% with respect to methacrylic acid. Swelling behavior of hybrid hydrogels and caffeine release was investigated in two environments which simulated human stomach and intestines. Obtained results showed that targeted delivery of poorly water-soluble model drug was achieved and that its release can be prolonged up to 24h. Also, kinetic of poorly water-soluble drug release can be easily modified only by changing crosslinker amount. PMAC hybrid hydrogels have huge potential for targeted delivery of poorly water-soluble active substances.

The effect of contaminants on Rio de Janeiro's beaches surface waves -a mathematical exactly soluble model

We model the effect of contaminants on the coastal waves beaches by means of a fluid with an effective shear viscosity