Vortex astigmatic Fourier-invariant Gaussian beams.

We find a two-parameter family of astigmatic elliptical Gaussian (AEG) optical vortices, which are free space modes up to scale and rotation. We calculate total normalized orbital angular momentum of AEG vortices, which can be an integer, fractional and zero, and which is equal to the algebraic sum of two terms reflecting the contribution of the vortex and astigmatic components of the light field. In any transverse plane, such a beam has an isolated n-fold degenerate intensity null on the optical axis (an optical vortex) embedded into an elliptical Gaussian beam. In addition to the quadratic elliptical phase, a beam has the phase of a cylindrical lens rotated by an angle of 45 degrees with respect to the principal axes of the ellipse of the Gaussian beam intensity distribution. The degenerated central intensity null in these beams does not split it into n spatially separated intensity nulls, as is usually assumed for elliptical astigmatic beams.

Orbital angular momentum of superposition of identical shifted vortex beams.

We have formulated and proven the following theorem: the superposition of an arbitrary number of arbitrarily off-axis, identical nonparaxial optical vortex beams of arbitrary radially symmetric shape, integer topological charge n, and arbitrary real weight coefficients has the normalized orbital angular momentum (OAM) equal to that of individual constituent identical beams. This theorem enables generating vortex laser beams with different (not necessarily radially symmetric) intensity profiles but identical OAM. Superpositions of Bessel, Hankel-Bessel, Bessel-Gaussian, and Laguerre-Gaussian beams with the same OAM are discussed.

Superpositions of asymmetrical Bessel beams.

We considered nonparaxial asymmetrical Bessel modes of the first and second types, which differ from a conventional symmetrical Bessel mode by a real-valued shift along one Cartesian coordinate and an imaginary shift along another (both shifts are equal in modulus). The first- and second-type Bessel modes differ only in signs of the shift and, therefore, have different orbital angular momentum (OAM) (integer or fractional). Addition and subtraction of complex amplitudes of two identical asymmetrical Bessel modes of the first and second type lead to light beams with the same integer OAM equal to the topological charge n of the original mode, but with different transverse intensity distributions, which depend on the shift magnitude. This proposed method allows controlling of the OAM of the beam with simultaneous changing of its shape, i.e., for matching with the object being trapped.

Vortex Hermite-Gaussian laser beams.

We study elliptical vortex Hermite-Gaussian (vHG) beams, which are described by the complex amplitude proportional to the nth-order Hermite polynomial whose argument is a function of a real parameter a. At |a|<1, on the vertical axis of the beam cross section, there are n isolated optical nulls that produce optical vortices with topological charge +1(a<0) or -1(a>0). At |a|>1, similar isolated optical nulls of the vHG beams are found on the horizontal axis. At a=0, the vHG beam becomes identical to the HG mode of the order (0,n). We derive the orbital angular momentum (OAM) of the vHG beams, which depends on the parameter a and an ellipticity parameter of the Gaussian beam. The derived equation allows the transverse intensity of the vHG-beam to be changed without changing its OAM. The experimental and theoretical results are in good agreement.

Asymmetric Bessel-Gauss beams.

We propose a three-parameter family of asymmetric Bessel-Gauss (aBG) beams with integer and fractional orbital angular momentum (OAM). The aBG beams are described by the product of a Gaussian function by the nth-order Bessel function of the first kind of complex argument, having finite energy. The aBG beam's asymmetry degree depends on a real parameter c≥0: at c=0, the aBG beam is coincident with a conventional radially symmetric Bessel-Gauss (BG) beam; with increasing c, the aBG beam acquires a semicrescent shape, then becoming elongated along the y axis and shifting along the x axis for c≫1. In the initial plane, the intensity distribution of the aBG beams has a countable number of isolated optical nulls on the x axis, which result in optical vortices with unit topological charge and opposite signs on the different sides of the origin. As the aBG beam propagates, the vortex centers undergo a nonuniform rotation with the entire beam about the optical axis (c≫1), making a π/4 turn at the Rayleigh range and another π/4 turn after traveling the remaining distance. At different values of the c parameter, the optical nulls of the transverse intensity distribution change their position, thus changing the OAM that the beam carries. An isolated optical null on the optical axis generates an optical vortex with topological charge n. A vortex laser beam shaped as a rotating semicrescent has been generated using a spatial light modulator.

Asymmetric Bessel modes.

We propose a new, three-parameter family of diffraction-free asymmetric elegant Bessel modes (aB-modes) with an integer and fractional orbital angular momentum (OAM). The aB-modes are described by the nth-order Bessel function of the first kind with complex argument. The asymmetry degree of the nonparaxial aB-mode is shown to depend on a real parameter c≥0: when c=0, the aB-mode is identical to a conventional radially symmetric Bessel mode; with increasing c, the aB-mode starts to acquire a crescent form, getting stretched along the vertical axis and shifted along the horizontal axis for c≫1. On the horizontal axis, the aB-modes have a denumerable number of isolated intensity zeros that generate optical vortices with a unit topological charge of opposite sign on opposite sides of 0. At different values of the parameter c, the intensity zeros change their location on the horizontal axis, thus changing the beam's OAM. An isolated intensity zero on the optical axis generates an optical vortex with topological charge n. The OAM per photon of an aB-mode depends near-linearly on c, being equal to ℏ(n+cI1(2c)/I0(2c)), where ℏ is the Planck constant and In(x) is a modified Bessel function.

Diffraction integral and propagation of Hermite-Gaussian modes in a linear refractive index medium.

We derive a diffraction integral to describe the paraxial propagation of an optical beam in a graded index medium with the permittivity linearly varying with the transverse coordinate. This integral transformation is irreducible to the familiar ABCD transformation. The form of the integral transformation suggests that, unlike a straight path in a homogeneous space, any paraxial optical beam will travel on a parabola bent toward the denser medium. By way of illustration, an explicit expression for the complex amplitude of a Hermite-Gaussian beam in the linear index medium is derived.

Hermite-Gaussian modal laser beams with orbital angular momentum.

A relationship for the complex amplitude of generalized paraxial Hermite-Gaussian (HG) beams is deduced. We show that under certain parameters, these beams transform into the familiar HG modes and elegant HG beams. The orbital angular momentum (OAM) of a linear combination of two generalized HG beams with a phase shift of π/2, with their double indices composed of adjacent integer numbers taken in direct and inverse order, is calculated. The modulus of the OAM is shown to be an integer number for the combination of two HG modes, always equal to unity for the superposition of two elegant HG beams, and a fractional number for two hybrid HG beams. Interestingly, a linear combination of two such HG modes also presents a mode that is characterized by a nonzero OAM and the lack of radial symmetry but does not rotate during propagation.

Role of ABC-cassette transporters (MDR1, MRP1, BCRP) in the development of primary and acquired multiple drug resistance in patients with early and metastatic breast cancer.

UNLABELLED: The aim of the research was to study the influence of multiple drug resistance (MDR1), multidrug resistance protein 1 (MRP1) and breast cancer resistance protein (BCRP) proteins expression on the effectiveness of chemotherapy in breast cancer (BC) patients. PATIENTS AND METHODS: The retrospective analysis of the results of treatment of 77 women with invasive BC with different molecular subtypes at the age of 54.1±12.5, who received treatment in Zaporizhzhya Regional Clinical Oncological Dispensary during 2011-2013, has been carried out. 23 (29.8%) patients were in II stage of disease, 32 (41.5%) - in III stage, 22 patients (28.5%) - IV stage. Neoadjuvant therapy has been given to 34 (44.2%) patients, palliative therapy in connection with presence of hematogenous visceral and bone metastases - to 43 (55.8%) patients. Transport proteins BCRP, MRP and PGP have been studied in tissues of primary BC tumor, in tissues of visceral metastases, in metastatically altered regional lymph nodes, as well as in circulating in blood tumor cells (CTC). In every case, 1000 of tumor cells has been calculated. The intensity of staining (0, 1+, 2+, 3+), percentage of stained cells (threshold has constituted 10%) and homogeneity of tumor cells staining (homogeneous was considered 80% staining of cytoplasm or membrane of studied cells) has been taken in consideration. RESULTS: Retrospective analysis has determined the dependence of results of polychemotherapy (PCT) on level and pattern of expression of BCRP, MRP and PGP proteins. In 1(st) group, in the absence thereof expression of transport proteins in BC cells, the objective response (CR + PR) from the tumor has been observed in 17 out of 18 patients (94.4%). In 2nd group (only cytoplasmic staining) the objective response has been observed in 36 patients (85.7%). Ineffectiveness of therapy and tumor progression in this group has been observed in 6 (14.2%) patients. In 3(rd)group (high membrane BCRP, MRP and PGP expression), in 14 out of 17 patients (82.3%), during the PCT occurred progression of the disease. Malignant phenotype of this tumor corresponded with the state of primary multiple drug resistance. In 80.0% of patients of this group, the neoadjuvant therapy turned out to be ineffective. CONCLUSION: Clinical trials for determination of role of ABC-transporters in the development of drug resistance of BC patients have not yet ended. The leading role in development of resistance of BC cells plays not only PGP, but also MRP1 and BCRP. Marker of resistance is not cytological, but membrane staining of cell.

[The role of radiofrequency thermoablation in the treatment of primary and metastatic hepatic cancer].

The experience of the method of radiofrequency thermoablation in complex of treatment in 95 patients, suffering primary and metastatic hepatic cancer, was summarized. The lower complications rate, the shorter rehabilitation period in the patients in comparison with those indices after hepatic resection performance, the possibility to achieve the late results, comparable with those in surgical treatment, constitute the method advantages.

Generating hypergeometric laser beams with a diffractive optical element.

We derive explicit analytical relations to describe paraxial light beams that represent a particular case of the hypergeometric (HyG) laser beams [J. Opt. Soc. Am. A25, 262-270 (2008)JOAOD60740-323210.1364/JOSAA.25.000262]. Among these are modified quadratic Bessel-Gaussian beams, hollow Gaussian optical vortices, modified elegant Laguerre-Gaussian beams, and gamma-HyG beams. Using e-beam microlithography, a binary diffractive optical element capable of producing near-HyG beams is synthesized. Theory and experiment are in sufficient agreement. We experimentally demonstrate the ability to rotate dielectric microparticles using the bright diffraction ring of a HyG beam.

Sidelobe contrast reduction for optical vortex beams using a helical axicon.

We present a new approach for generating an optical vortex pattern with reduced sidelobes without increasing the radius of the vortex and without excessive energy loss. Our technique combines the spiral phase plate with a weak axicon to form a helical axicon. Experimental results using a liquid crystal display agree with theory.

Diffraction of a plane, finite-radius wave by a spiral phase plate.

We derive analytical expressions containing a hypergeometric function to describe the Fresnel and Fraunhofer diffraction of a plane wave of circular and ringlike cross section by a spiral phase plate (SPP) of an arbitrary integer order. Experimental diffraction patterns generated by an SPP fabricated in resist through direct e-beam writing are in good agreement with the theoretical intensity distribution.

[The radiofrequence ablation of colonic cancer metastases in liver].

Therapeutic efficacy of the radiofrequence thermoablation (RFTHA) method was studied, basing on analysis of the treatment results of 18 patients, in whom 65 metastatic hepatic tumors were revealed. Results of RFTHA of the colonic cancer metastases in liver are comparable with such after their surgical resection.

[Surgical strategies in spontaneous rupture of renal allograft]. / Khirurgicheskaia taktika pri spontannom razryve pochechnogo allotransplantata.

The methods of surgical treatment of spontaneous rupture of renal allotransplant (RAT) were studied up in 21 patients. In 17 (80.9%) of patients the RAT rupture was caused by an acute reaction of rejection (ARR), in 14.3% of observations--by an acute necrosis of tubules, in 2 (9.5%)--by renal vein thrombosis and in 2 (9.5%)--by an ischemic damage of the transplant. Surgical treatment of the RAT spontaneous rupture (except the cases with rupture due to renal vein thrombosis) must be managed by the hemorrhage stoppage, the RAT tissues strain reduction (decapsulation and the cross-like capsulotomy), conduction of its intraoperative anticrisis and antiischemic defense with subsequent complex therapy for ARR and the transplant dysfunction. Application of such a tactics of treatment have permitted to secure the RAT and its functions in spontaneous rupture in 82.4% of observations. The transplant survival was registered in terms up to one year in 64.7% of observations.

[Diagnosis of bladder cancer]. / Diagnostika raka mochevogo puzyria.

Increasing incidence of bladder tumors necessitates development of new techniques of early diagnosis. A total clinical system including application of ultrasonoangiography proved superior to examination under the gray scale mode. The diagnostic and monitoring algorithm makes the system highly effective.

[Surgical treatment of diseases of the operated stomach]. / Khirurgicheskaia korrektsiia boleznei operirovannogo zheludka.

The experience of treatment of 303 patients with the operated stomach diseases (OSD) is summarized. It was established that to reduce the frequency of their occurrence it is necessary: to perform vagotomy especially selective proximal (SPV) thoroughly for complete acid producing zone denervation achievement; to examine gastric cardia and pyloroduodenal zone before and intraoperatively thoroughly to select an optimal method of its drainage; to conduct conservative therapy of ulcer disease after vagotomy conduction up to the ulcer defect healing according to endoscopic control data.

Effect of unconscious interoceptive afferentation on the spatial organization of electrical activity in the human cerebral cortex.

Toposcopic studies consisting of EEG recording from 24 cortical points was carried out to characterize the spatial organization of the electrical activity of the human cerebral cortex during the action of unconscious interoceptive stimuli arising from biologically active points associated with different internal organs-the heart, lungs, liver, and intestine. When acupuncture had positive effects, reductions in global synchronization of cortical potentials were noted, which were combined with foci of weakening of the linear and nonlinear correlations in the anterior parts of the right hemisphere, as well as in the posterior and temporal parts of the left hemisphere, with increases in coherence in one of the high-frequency subranges of the EEG (21.5-23.0 Hz). Negative effects and absence of effect correlated with significantly less pronounced weakening of global synchronization of potentials, and increases in their coherence in one of the subranges of alpha activity.

[Surgical treatment of insulin-dependent diabetes mellitus and its complications]. / Khirurgicheskoe lechenie insulinzavisimogo sakharnogo diabeta i ego oslozhnenii.

Free xenotransplantation of cryopreserved Langerhans cells (67 cases) and deportalization of pancreatic blood supply (37 patients) was done in 104 patients with insulin-dependent diabetes mellitus with positive effect. There were 58 men and 46 women at the age of 16-62 years. In 15 cases the combination of these two methods has been used that made it possible to enforce the antidiabetic effect and stabilize the development of diabetic complications.