9 research outputs found
Performances and stability of a 2.4 ton Gd organic liquid scintillator target for antineutrino detection
In this work we report the performances and the chemical and physical
properties of a (2 x 1.2) ton organic liquid scintillator target doped with Gd
up to ~0.1%, and the results of a 2 year long stability survey. In particular
we have monitored the amount of both Gd and primary fluor actually in solution,
the optical and fluorescent properties of the Gd-doped liquid scintillator
(GdLS) and its performances as a neutron detector, namely neutron capture
efficiency and average capture time. The experimental survey is ongoing, the
target being continuously monitored. After two years from the doping time the
performances of the Gd-doped liquid scintillator do not show any hint of
degradation and instability; this conclusion comes both from the laboratory
measurements and from the "in-tank" measurements. This is the largest stable
Gd-doped organic liquid scintillator target ever produced and continuously
operated for a long period
Fizikalni mehanizmi i metode u tumorskim terapijama i prijenosu lijekova do tumora
In addition to several well-known drug delivery strategies developed to facilitate effective chemotherapy with anticancer agents, some new approaches have been recently established, based on specific effects arising from the applications of ultrasound, magnetic and electric fields on drug delivery systems. This paper gives an overview of newly developed methods of drug delivery to tumors and of the related anticancer therapies based on the combined use of different physical methods and specific drug carriers. The conventional strategies and new approaches have been put into perspective to revisit the existing and to propose new directions to overcome the threatening problem of cancer diseases.Osim dobro poznatih metoda prijenosa lijekova u kemoterapijskom pristupu liječenja tumora, nedavno su otkriveni novi načini prijenosa koji se zasnivaju na specifičnim mehanizmima uzrokovanim upotrebom ultrazvuka, magnetskih i električnih polja. Članak sadrži prikaz fizikalnih mehanizama na kojima se temelje ove nove metode, kao i pregled novootkrivenih prijenosnika lijekova (Pluronske micele, magnetoliposomi, magnetski fluidi), novih terapija tumora (magnetska hipertermija, elektrokemoterapija) i najnovijih istraživanja temeljenih na fizikalnom pristupu ovoj problematici
Vibrational Relaxation of Adsorbed Molecules. Mechanisms and Manifestations in Chemical Reactions on Solid Surfaces
OPLS3: A Force Field Providing Broad Coverage of Drug-like Small Molecules and Proteins
The
parametrization and validation of the OPLS3 force field for
small molecules and proteins are reported. Enhancements with respect
to the previous version (OPLS2.1) include the addition of off-atom
charge sites to represent halogen bonding and aryl nitrogen lone pairs
as well as a complete refit of peptide dihedral parameters to better
model the native structure of proteins. To adequately cover medicinal
chemical space, OPLS3 employs over an order of magnitude more reference
data and associated parameter types relative to other commonly used
small molecule force fields (e.g., MMFF and OPLS_2005). As a consequence,
OPLS3 achieves a high level of accuracy across performance benchmarks
that assess small molecule conformational propensities and solvation.
The newly fitted peptide dihedrals lead to significant improvements
in the representation of secondary structure elements in simulated
peptides and native structure stability over a number of proteins.
Together, the improvements made to both the small molecule and protein
force field lead to a high level of accuracy in predicting protein–ligand
binding measured over a wide range of targets and ligands (less than
1 kcal/mol RMS error) representing a 30% improvement over earlier
variants of the OPLS force field