Chronobiological approaches to antiangiogenic photodynamic therapy of tumors: the first experimental evaluatIon

In research of the last decade, rhythmic (circadian) variations of vascular endothelial growth factor (VEGF) production by tumors were discovered. The present paper authors have earlier synthesized and characterized a new derivative photosensitizer — an immunoconjugate of hematoporphyrin with antiVEGF antibodies. Aim: To elaborate and to test a novel modification of the photodynamic therapy of tumors (PDT) method, founding upon a timed introduction of the immunoconjugated photosensitizer to tumor-bearing animals, so that this coincides with a maximum content of VEGF in tumor tissues. Methods: Circadian variations of VEGF contents in murine transplanted tumors, Lewis lung carcinoma and sarcoma 180, were determined by ELISA method. Immunoconjugated photosensitizer concentrations in tumors were estimated by spectrofluorometry. Photoirradiation of the tumors was carried out with a red light (wavelength of 635 nm) from a semiconductor laser. Light doses were chosen, calculating on a partial inhibition of tumor growth, in order that a dependence of PDT efficiency on a daily time-moment (circadian rhythm phase) of the treatment could be observed distinctly. Results: Circadian variations of the VEGF levels in Lewis lung carcinoma and sarcoma 180 were demonstrated with the maximum at 14:00 h and the minimum at 02:00 h. Intra-abdominal introduction into tumor-bearing mice of the immunoconjugated photosensitizer resulted in a greater accumulation of the immunoconjugate in tumors at 14:00 h than at 02:00 h. Laser irradiation of carcinomas and sarcomas at 14:00 h or 02:00 h after introduction of the immunoconjugated photosensitizer to mice the day before at the same time points, induced a significantly enhanced inhibition of tumor growth in animals treated at day-time versus those treated at night-time. Conclusion: The obtained results justify further attempts to transfer principles of tumor chronochemotherapy onto photodynamic therapy

Energy losses of a point magnetic dipole due to interaction with a magnetized plasma cylinder

In this work, the excitation problem of bulk-surface helicons by a point magnetic dipole moving in a vacuum parallel to the element of magnetized solid-state plasma cylinder is theoretically studied. The external magnetic field is directed parallel to the cylinder axis. The problem is solved in the magnetostatic approximation. It is shown that hybrid modes of the magnetic type with large values of the azimuthal mode index and one field variation along the radius are most efficiently excited at nonrelativistic velocities of magnetic dipole.Теоретично вивчено задачу про збудження об'ємно-поверхневих геліконів точковим магнітним диполем, що рухається у вакуумі паралельно твірним замагніченого твердотільного плазмового циліндра. Зовнішнє магнітне поле направлено паралельно осі циліндра. Задача розв'язана в магнітостатичному наближенні. Показано, що гібридні моди магнітного типу з великими значеннями азимутального модового індексу і з однією варіацією поля вздовж радіуса найбільш ефективно збуджуються в разі нерелятивістських швидкостей магнітного диполя.Теоретически изучена задача о возбуждении объемно-поверхностных геликонов точечным магнитным диполем, движущимся в вакууме параллельно образующим замагниченного твердотельного плазменного цилиндра. Внешнее магнитное поле направлено параллельно оси цилиндра. Задача решена в магнитостатическом приближении. Показано, что гибридные моды магнитного типа с большими значениями азимутального модового индекса и с одной вариацией полей по радиусу наиболее эффективно возбуждаются при нерелятивистских скоростях магнитного диполя

Nanoprobe spectroscopy of capillary forces and its application for a real surface diagnostics

The paper presents an overview and analysis of the most reliable and at the same time rather simple theoretical models describing liquid nanomeniscus geometry and forces occurring between atomic force microscope (AFM) probe and a real surface. There are experimental results in capillary bridge force rupture measured in air, and interaction force under water buffer obtained over surfaces of different nature. It is shown that the theoretical models quite adequately describe the processes observed experimentally and, in particular, bridge ruptures dynamics at the vertical probe withdraw for different speeds. Discussed here are some methodological peculiarities and nanocapillary force spectroscopy diagnostic capabilities for surface energy mapping, prospects of using of a liquid nanomeniscus in local nanochemistry, nanolithography and nano-electrochemistry of a surface

Recrystallization processes in screen-printed CdS films

Kinetics of recrystallization in screen-printed polycrystalline CdS films has been investigated by X-ray structure analysis and optical microscopy. The relation between the crystallite size, crystallite orientation and the macrostrain, as well as their dependence on heat treatment regimes is established. It is shown that single-phase CdS films having a thickness of some tens microns, large grain size and low residual strain can be produced at optimum technological regimes. The films obtained are suitable for fabrication of CdS/CdTe solar cells

Search for Higgs bosons decaying to tautau pairs in ppbar collisions at sqrt(s) = 1.96 TeV

We present a search for the production of neutral Higgs bosons decaying into tautau pairs in ppbar collisions at a center-of-mass energy of 1.96 TeV. The data, corresponding to an integrated luminosity of 5.4 fb-1, were collected by the D0 experiment at the Fermilab Tevatron Collider. We set upper limits at the 95% C.L. on the product of production cross section and branching ratio for a scalar resonance decaying into tautau pairs, and we then interpret these limits as limits on the production of Higgs bosons in the minimal supersymmetric standard model (MSSM) and as constraints in the MSSM parameter space.Comment: 7 pages, 5 figures, submitted to PL

Measurement of the photon+b+b-jet production differential cross section in ppˉp\bar{p} collisions at \sqrt{s}=1.96~\TeV

We present measurements of the differential cross section dsigma/dpT_gamma for the inclusive production of a photon in association with a b-quark jet for photons with rapidities |y_gamma|< 1.0 and 30<pT_gamma <300 GeV, as well as for photons with 1.5<|y_gamma|< 2.5 and 30< pT_gamma <200 GeV, where pT_gamma is the photon transverse momentum. The b-quark jets are required to have pT>15 GeV and rapidity |y_jet| < 1.5. The results are based on data corresponding to an integrated luminosity of 8.7 fb^-1, recorded with the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider at sqrt(s)=1.96 TeV. The measured cross sections are compared with next-to-leading order perturbative QCD calculations using different sets of parton distribution functions as well as to predictions based on the kT-factorization QCD approach, and those from the Sherpa and Pythia Monte Carlo event generators.Comment: 10 pages, 9 figures, submitted to Phys. Lett.

Limits on anomalous trilinear gauge boson couplings from WW, WZ and Wgamma production in pp-bar collisions at sqrt{s}=1.96 TeV

We present final searches of the anomalous gammaWW and ZWW trilinear gauge boson couplings from WW and WZ production using lepton plus dijet final states and a combination with results from Wgamma, WW, and WZ production with leptonic final states. The analyzed data correspond to up to 8.6/fb of integrated luminosity collected by the D0 detector in pp-bar collisions at sqrt{s}=1.96 TeV. We set the most stringent limits at a hadron collider to date assuming two different relations between the anomalous coupling parameters Delta\kappa_\gamma, lambda, and Delta g_1^Z for a cutoff energy scale Lambda=2 TeV. The combined 68% C.L. limits are -0.057<Delta\kappa_\gamma<0.154, -0.015<lambda<0.028, and -0.008<Delta g_1^Z<0.054 for the LEP parameterization, and -0.007<Delta\kappa<0.081 and -0.017<lambda<0.028 for the equal couplings parameterization. We also present the most stringent limits of the W boson magnetic dipole and electric quadrupole moments.Comment: 10 pages, 5 figures, submitted to PL