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The BM@N (Baryonic Matter at Nuclotron) is the first experiment in operation at the NICA-Nuclotron accelerator complex. The BM@N scientific program comprises the study of dense nuclear matter produced in heavy-ion collisions in the intermediate energy range between the SYS-18 and NICA/FAIR facilities. The first experiments were performed with deuteron and carbon beams with kinetic energy ranging from 3.5 to 4.5 GeV per nucleon on fixed targets. An extended configuration of the BM@N setup was realized in the next runs with argon and krypton beams. First preliminary physics results are presented on $$\Lambda $$ hyperon production in carbon–nucleus interactions at a beam kinetic energy of 4 GeV per nucleon. Signals of $$\Lambda $$ hyperons, charged pions, kaons and light nuclear fragments are identified in argon–nucleus interactions. The performance of the upgraded BM@N central tracker is evaluated for the reconstruction of strange particles and hypernuclei in heavy-ion interactions.

In present days the evolution of broad-band laser pulses, propagating in various types of waveguides, has been of a great interest among the scientists. Currently, it is easy for phase-modulated femtosecond pulses the condition Δω≈ω0 to be obtained. It is known that nowadays it is possible also to reach the attosecond region where the spectral bandwidth of the pulse happens to be of order of the carrier frequency also. Light pulses who fulfil this initial condition are called broad-band. On the other hand, the non-fulfilling pulses are the narrow-band ones. In the present paper it is investigated the parametric interaction of two components of one optical pulse by using the Generalized System of Nonlinear Amplitude Equations (GSNAE). GSNAE was analytically solved. A difference in the period of oscillations of the energy exchange between the two components is found.

In the present work the soliton regime of propagation in air of ultra-short long-wavelength infrared laser pulses is investigated. The dispersion of atmospheric air in mid-infrared and long-wavelength infrared shows anomalous group velocity dispersion regions for wavelengths in the ranges of 3.5 to 4.2μm and 9.3 to 13.5μm. In these spectral regions the atmospheric air is transparent. From other hand, the nonparaxiality leads to waveguiding regime of propagation for femtosecond pulses with shape of light disks (the transverse size is much bigger than the longitudinal one). It allows reducing this 3D + 1 task to 1D + 1 problem in the same manner as in optical fibers. The combination between anomalous group velocity dispersion and atmospheric nonlinearity is a base for the observation of optical solitons in the air transparency regions for the indicated wavelengths. The main equation in our research is the 1D + 1 nonlinear nonparaxial amplitude equation, written in Galilean and Laboratory coordinate systems. New analytical solution in the form of bright soliton is found. The critical power, needed for the observation of these solitons is of two orders of magnitudes less than the critical one for self-focusing. That is why there are no conditions for ionization of the media.

In the present work, the formation of vector-type vortex structures in isotropic media is studied. These vortices exist in the electric field components and generate a depolarization in the vector field of the laser spot. Their behavior is governed by a system of amplitude equations. Additionally, new solutions have been found that describe similar types of vortex structures in an optical fiber. The optical vortices admit only amplitude-type singularities. The vortex structures observed within the vector amplitude function have ring-like patterns. The variation of the intensities of the x and y components of the amplitude function along the axis of the fiber is investigated.

In the present paper the parametric interaction between two optical waves, which are propagating in few-mode optical fibers, is investigated. This occurs under the influence of the processes of third harmonic generation, self-phase modulation and cross-phase modulation. The generation of third-harmonic or THz generation in femtosecond region is described by a system of two coupled nonlinear differential equations. A new analytical solution of this system, which characterizes the periodic energy exchange between the two waves, is found. Depending on the wavenumber mismatch Δk, the obtained result can be used for studying different optical processes of generation of signal wave in nonlinear dispersive media. The mentioned effects are strongly related to modern optical sensors, parametric amplifiers and communication systems.

Particle knockout scattering experiments1,2 are fundamental for mapping the structure of atomic nuclei2–6, but their interpretation is often complicated by initial- and final-state interactions of the incoming and scattered particles1,2,7–9. Such interactions lead to reduction in the scattered particle flux and distort their kinematics. Here we overcome this limitation by measuring the quasi-free scattering of 48 GeV c–1 12C ions from hydrogen. The distribution of single protons is studied by detecting two protons at large angles in coincidence with an intact 11B nucleus. The 11B detection suppresses the otherwise large distortions of reconstructed single-proton distributions induced by initial- and final-state interactions. By further detecting residual 10B and 10Be nuclei, we also identified short-range correlated nucleon–nucleon pairs9–13 and provide direct experimental evidence for separation of the pair wavefunction from that of the residual many-body nuclear system9,14. All measured reactions are well described by theoretical calculations that include no distortions from the initial- and final-state interactions. Our results showcase the ability to study the short-distance structure of short-lived radioactive nuclei at the forthcoming Facility for Antiproton and Ion Research (FAIR)15 and Facility for Rare Isotope Beams (FRIB)16 facilities, which is relevant for understanding the structure and properties of nuclei far from stability and the formation of visible matter in the Universe. Initial- and final-state interactions distort the kinematics in particle knockout scattering experiments, complicating their interpretation. These effects are suppressed by detecting 11B nuclei in quasi-free scattering of 12C ions from hydrogen.

We present experimental and theoretical investigation of the first picoseconds of formation of white continuum from 100 fs laser pulse in 0.5 cm BK7 glass. The theory gives an answer to the question of the physical mechanism of asymmetrical ultra-broadening of the pulses in the initial moment of filamentation. The spectra obtained from the experiment are compared with the spectrum profiles of the physical model and are in very good coincidence.

Fragments containing the coat protein gene of beet necrotic yellow vein virus were cloned in two plant transformation vectors: pCAMBIA3301M with the bar gene as selectable marker, and pCAMBIA1304M, with resistance to hygromycin. Three constructs were made of each vector: CPL, containing coat protein gene with leader sequence; CPS with coat protein gene, and CPSas with coat protein gene in antisense orientation. Vectors pC3301MCPL, pC3301MCPS. and pC3301MCPSas were used in Agrobacterium—mediated transformation of Nicotiana tabacum (tobacco), Nicotiana excelsior and Nicotiana benthamiana. Regenerants that developed roots on selective media were tested for the presence of CP fragments and the bar gene, but most regenerants were nontransformed (50-83% escapes). After all rooted plants had been selfed, and T1 seed germinated on selective media, only plants descending from one N. excelsior regenerant transformed with pC3301MCPS were positive for presence of bar gene and CPS fragment. Tobacco and Nicotiana benthamiana were transformed with constructs pC1304MCPS and pC1304MCPSas. Transformation efficiency was much higher and approximately 50% of regenerants that rooted on media with 20 mg l−1 hygromycin were positive for the presence of CP fragments. All T1 plants were positive for presence of CP fragments.

Since 1999 Vilnius Gediminas Technical University has already introduced three e-learning Master's degree programmes. This paper proposes a way to integrate augmented reality and computer learning systems. In order to demonstrate the integration of the above systems in building refurbishment projects, the Building Refurbishment Computer Learning System with Augmented Reality (BR-CLS-AR) has been developed. The authors of this paper participated in the project "Learning Augmented Reality Global Environment" (LARGE), part of the Lifelong Learning Programme. One of LARGE's goals (on the part of Lithuania) was to integrate augmented reality and computer learning systems (i.e. to develop the BR-CLS-AR). To check the accuracy of the system, its entire solution process was reproduced manually. The results of the manual calculations matched those produced by the computer. Moreover, each individual phase in the system and its subsystems was checked with experts in this field, i.e. the underlying calculations were found to be in conformity with the experts' logical reasoning. Owing to the suggestions from these experts, some useful changes have been introduced in the system. The BR-CLS-AR consists of a computer learning subsystem and an augmented reality subsystem.

An analytical approach to the theory of electromagnetic waves in nonlinear vacuum is developed. The evolution of the pulse is governed by a system of nonlinear wave vector equations. An exact solution with its own angular momentum in the form of a shock wave is obtained.

Up to now the long range filaments are considered as a balance between Kerr focusing and defocusing by plasma generation in the nonlinear focus. However, the above explanation of filamentation in far-away zone finds considerable difficulties. There are basically two main characteristic which remain the same at these distances - the super broad spectrum and the width of the core, while the power in a stable filament drops to the critical value for self-focusing. With such power the plasma and higher-order Kerr terms are too small to prevent selffocusing. We suggest here a new mechanism for stable soliton pulse propagation in far-away zone, where the power of the laser pulse is a little above critical, and the pulse admits super-broad spectra.

In linear regime the single and few cycle femtosecond (fs) pulses propagates on several diffraction lengths changing their shape in semi-spherical (or parabolic) form, far away from plane wave and paraxial approximation. The experiments with fs pulses in air with power little above the critical for self-focusing (nonlinear regime) demonstrated new nonlinear effects as self-guiding, THz longitudinal emission and superbroad enlarging of the spectrum. In this paper we continue with developing of new theoretical model for quantitative description of the above experimental results.

For the last two decades a new techniques has been used for the rectum tumor treatment. While sphincter sparing of it upper third localization is with favorable functional results, the same in mid and lower third is questionable. The correct surgical approach could have a positive influence on the quality of life in these patients. Pouch interposition, for example, could help some unpleasant after-effects of the "low" operations to be avoided.

In the present work it is demonstrated two efficient methods of self-compression of femtosecond pulses based on suitable selection of optical elements, parameters of the medium and laser radiation. The basic idea is that the phase modulated pulses more efficiently can be compressed trough nonlinear mechanisms. The first method can be applied for mediums with significant dispersion like fused silica, where the sign of the dispersion of the group velocity is important. We show that the combination of focusing by optical lens and a balance between anomalous dispersion and nonlinearity lead to significant compression from 100fs to~20-30fs of optical pulse. The second method for self-compression is by using only one optical diffraction grating to obtain broadband pulses and the following self-compression in nonlinear regime. In the second case in addition is observed generation of X wave.

We investigate the nonlinear vector amplitude equation governing the evolution of optical pulses. We reduce the amplitude equation to the 3D+1 Vector Nonlinear Schrodinger Equation. Conditions for experimental observation of the vortex solutions are discussed.

An intraduodenal diverticulum in 54 year old woman which caused alcalculous cholecystitis and pancreatitis is described. The diverticulum was missed at the first operation, performed for acute cholecystitis. Before the second it was interpreted as a pancreatic cyst. At the second intervention, the cyst wall was excised through a duodenotomy. Histological examination of the wall of the diverticulum is crucial for correct diagnosis.

The results of perioperative decontamination in a series of 136 patients presenting diseases of the colon and rectum are evaluated. Of the total 74 are subjected to operation according to schedule, and 62 are operated on an emergency basis. Perioperatively, metronidazole plus a cephalosporin antibiotic (cephazolin, cephalothin or cephamandol) are administered. Primary anastomoses are done in 32 cases operated according to schedule, and in fourteen patients operated in the emergency room. Insufficiency of the anastomosis is recorded in 3.5 per cent in the former group, and in 15 per cent in the latter group (p0.05). Operative wound suppuration occurs in 5.4 per cent against 13 per cent (p0.05), with lethality amounting to 1.3 per cent and 19 per cent, respectively (p0.001). Postoperative pneumonia is registered in 4 per cent of those operated on schedule and in 9.6 per cent of those operated by urgency (p0.05). In either group there is not a single case of operative wound dehiscence. In colorectal operations antibacterial prophylaxis applied perioperatively proves effective in combating systemic and local inflammatory complications.

Data concerning the therapeutic approach in a series of 28 patients, representing 1.3 per cent of the total number of abdominal operations performed in the Chair of Propedeutics of Surgical Diseases over the period 1990-1995, are retrospectively analyzed. In 19 of them primary operative interventions are done on an emergency basis. In further 19 cases the complications have inflammatory character. A total of 31 operations are done with lethality amounting to 36 per cent (10 patients). Multiorganic insufficiency develops in five of them (mean age 39 years). The remainder, dying of septic complications, are with mean age 76 years. The successful treatment of intraabdominal postoperative complications is largely dependent on the surgeon's experience and skills, material equipment and facilities available and on the algorithm of the therapeutic approach adopted.

The treatment results is a series of twenty-six patients running a very serious course of soft-tissue infections are analyzed. Of the total number ten have diabetes mellitus. The sepsis severity score is 23 average according to the APACHE II rating system. Operative management is undertaken without any delay. It is preceded by comprehensive correction of the metabolic disorders present and antibiotic treatment, initially substantiated by presumable microbial causing agents. A total of 62 operations are done. In 36 per cent of cases being examined, the microbiological study contributes to a proper orientation of the antibiotic therapy performed. Bacteremia is documented in three instances. Total mortality rate amounts to 32 per cent (8 patients). Infections running a serious clinical course may be caused by one or more microorganisms, but in either case the lethality is noteworthy. Active surgical management may prove effective provided it is initiated in the most opportune time. It is only part of the complex therapeutic approach to sepsis.

Experience had with application of spleen salvaging operations in adult patients is shared. They are used traumatic lesions of the spleen in eleven patients, employing the method of Delany, as modified with the Bulgarian polyamide meshwork Ampoxen. In two of them the hemostasis fails, and splenectomy is resorted to. Preservation of the spleen is accomplished in one patient with chronic pancreatitis where left pancreatectomy with spleen preservation according to the technique of Pradere et al is done. In another female patient, presenting echinococcus of the spleen, echinococcectomy with preservation of the organ is performed. Based on updated knowledge of the role played by the spleen in promoting protection against infection, the strive for its salvage whenever possible is fully justified.

The treatment results in 312 patients with cholelithiasis, covering the period 1989 to 1993, are retrospectively analyzed. Overall postoperative lethality amounts to 4.4 per cent. The obtained results are fully comparable in terms of both missed concrements left behind within the extrahepatic bile ducts, and in terms of postoperative complications, associated with the indications for choledochotomy. This is attributed to the therapeutic approach algorithm adopted with respect to the indications for intraoperative cholangiography and choledochotomy.

We present the corrected version of the diffraction length of a laser pulse verified with the exact solution of amplitude equation (24) in J. Opt. Soc. Am. A25, 2232 (2008) in real (not normalized) coordinates.

We present a systematic study of linear propagation of ultrashort laser pulses in media with dispersion, dispersionless media, and vacuum. The applied method of amplitude envelopes makes it possible to estimate the limits of the slowly varying amplitude approximation and to describe an amplitude integrodifferential equation governing propagation of optical pulses in the single-cycle regime in solids. The well-known slowly varying amplitude equation and the amplitude equation for the vacuum case are written in dimensionless form. Three parameters are obtained defining different linear regimes of optical pulse evolution. In contrast to previous studies we demonstrate that in the femtosecond region the nonparaxial terms are not small and can dominate over the transverse Laplacian. The normalized amplitude nonparaxial equations are solved using the method of Fourier transforms. Fundamental solutions with spectral kernels different from those according to Fresnel are found. Exact unidirectional analytical solution of the nonparaxial amplitude equations and the 3D wave equations with initial conditions compatible with Gaussian light bullets are obtained also. One unexpected new result is the relative stability of light bullets (pulses with spherical and spheroidal spatial form) when we compare their transverse enlargement with paraxial diffraction of light beams in air. It is important to emphasize here the case of light disks, i.e., pulses whose longitudinal size is small with respect to the transverse one, which in some partial cases are practically diffractionless over distances of a thousand kilometers. A new formula that calculates the diffraction length of optical pulses is suggested. Finally, propagation of single-cycle pulses in air and vacuum was investigated, and a coronal (semispherical) form of diffraction at short distances was observed.

A total of 208 patients with diseases of the extremities, 56 of whom with diabetes mellitus, were included in the study. Septicemia developed in 6 patients, in 4 of them being caused by anaerobic pathogens. The following surgical interventions were performed: 193 incisions, 32 amputations of varying extent and 15 large-scale necrotomies. The case fatality rate was 1.44 per cent. To achieve superior therapeutic results and a better life for patients with diabetes mellitus, it is necessary to change the former approach to their long-term medical surveillance.

A method is described for producing continent colostomal by smooth-muscle sphincteroplasty. There are variants of operative technique: autogenic smooth-muscle intestinal grafting and pediculated plasty. A 10 cm long intestinal segment is split along the free tenia, mucosectomized and wrapped around the precolostomal part of the colon. Essential element of the operation is the 100 per cent stretching of the seromuscular flap when fixed. A tight sphincter-like cuff results. The method is unassociated with specific complications. The first impressions of the sphincteroplasty with encouraging results are recorded. In cases when no sphincter effect was obtained there was inadequacy in some elements of the operation. Then the stoma functions as a conventional one.

Coat protein gene of beet necrotic yellow vein virus (BNYVV) was isolated from inoculated sugar beet roots and leaves of Chenopodium quinoa and Tetragonia expansa, by RT-PCR and imuno capture RT-PCR. Specific primers were made to complement coat protein gene and untranslated leader sequence, so that two fragments were obtained: long (731 bp), which contained coat protein gene and leader sequence, and short (587 bp), with coat protein gene. Fragments were cloned in two plant transformation vectors: pCAMBIA 3301M and pCAMBIA 1304M, which were modified by removing multicloning site and NcoI restriction site at the 5' end of the reporter genes. Vector pC3301M had bar gene which confers resistance against the herbicide gluphosinate ammonium as selectable marker, and pC1304M had gene for resistance to antibiotic hygromycin. Three constructs were made from each vector: CPL, containing coat protein gene with leader sequence; CPS with gene for coat protein, and CPSas with coat protein gene in antisense orientation. All constructs were transfered to Agrobacterium tumefaciens strain LBA4404.