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This work is devoted to the studies performed at the Institute of Applied Physics of the Russian Academy of Sciences and aimed at the development of the photoinjector accelerator complex, which ensures formation of the electron bunches with charges of up to 100 pC and particle energies of 3 to 5 MeV. The key elements of the complex are described, namely, the accelerating cavity powered by the klystron with an operation frequency of 2.45 GHz and a power of 5 MW, a photocathode based on diamond films, a high-power ultraviolet laser, and a system for synchronizing the laser pulses with the phase of the accelerating microwave field. The design parameters of the components of the complex are presented, and the state of research related to its realization is discussed.

The physical reason for the difference between the small-scale self-focusing of nanosecond and femtosecond pulses is that the typical intensity of the latter is three orders of magnitude higher, i.e., TW/cm2 versus GW/cm2. This causes a significant shift of the growth-rate maximum of the Bespalov–Talanov instability to the region of high spatial frequencies. During free propagation, a decrease in the spectral density of noise and the self-filtering of the beam lead to the noise-density decrease in the region of the maximum growth rate and, therefore, slowing of the self-focusing development. This is shown to shift the restriction on using the transmissive optical elements in the superpower lasers towards high powers.

This paper presents the results of the work carried out by the Department for Metal Working Processes at NUST for production technology of: high-strength automotive flat stock from bi-phase ferrite martensite steels (BPHFMS) on a broad-strip hot-rolling mill by staged laminar cooling on a runoff table, as well as K52–56 strength grade cold- and corrosion-resistant tubular strip bar. The metal’s ferrite grains rolled on the broad-strip mill are ground by combining the controlled rolling (CR) of strips with their rapid cooling (RCL). Thermal kinetic diagrams (TKDs) were created to show modeling sheet cooling, as well as to predict the resulting structure type depending on the metal cooling rate.

A prototype of a direct-current photoinjector (DC) with an electron energy of up to 400 keV is being developed at JINR for future electron accelerators (electron-positron colliders and free-electron lasers). This article describes the injector, one distinctive feature of which is the use of the transmission photocathode operation mode. A unique laser system is implemented on the photoinjector. The system makes it possible to synchronize the repetition rate and the phase of the laser pulses (of 10 ps duration, 262 nm wavelength, and 1.85 μJ energy) with the frequency of the accelerator RF system. The first experimental results of a DC photoinjector are presented and further plans for the development of the installation are discussed.

We consider the possibility of generating the second and fourth optical harmonics of laser pulses having a central wavelength of 1030 nm with retaining the three-dimensional quasi-ellipsoidal intensity distribution. The presented results of numerical simulation confirm that angular chirping allows one to retain the three-dimensional structure of the intensity distribution and enhance energy conversion. The proposed approach was tested experimentally using non-profiled laser beams. Energy conversion efficiency of 53% and 21% was achieved in the generation of the second and fourth harmonics, respectively.

The use of high brightness electron beams in Free Electron Laser (FEL) applications is of increasing importance. One of the most promising methods to generate such beams is the usage of shaped photocathode laser pulses. It has already demonstrated that temporal and transverse flat-top laser pulses can produce very low emittance beams [1] . Nevertheless, based on beam simulations further improvements can be achieved using quasi-ellipsoidal laser pulses, e.g. 30% reduction in transverse projected emittance at 1 nC bunch charge. In a collaboration between DESY, the Institute of Applied Physics of the Russian Academy of Science (IAP RAS) in Nizhny Novgorod and the Joint Institute of Nuclear Research (JINR) in Dubna such a laser system capable of producing trains of laser pulses with a quasi-ellipsoidal distribution, has been developed. The prototype of the system was installed at the Photo Injector Test facility at DESY in Zeuthen (PITZ) and is currently in the commissioning phase. In the following, the laser system will be introduced, the procedure of pulse shaping will be described and the last experimental results will be shown.

The goal is to produce hot-rolled dual-phase steel of strength class DP 450–600 at OAO Novolipetskii Metallurgicheskii Kombinat (NLMK). The steel’s final structure and properties is greatly affected by single-stage strip cooling on the output roller conveyer of the 2000 continuous broad-strip mill. The influence of the hot-rolling parameters on the structure and mechanical properties of the hot-rolled SPRC440R steel from which cold-rolled dual-phase steel is produced at OAO NLMK is studied in the laboratory. The temperatures and rates for accelerated cooling on the output roller conveyer of the 2000 continuous broad-strip mill at OAO NLMK are calculated by means of a mathematical model. The laboratory data and simulation results are used in developing trial conditions for industrial rolling. Recommendations are made regarding the production of hot-rolled dual-phase steel corresponding to strength class DP 450–600.

Background Adhesions represent a major problem after abdominal and pelvic procedures. The purpose of the present study was to determine the effect of sunitinib (Sutent, SU11248), a Food and Drug Administration-approved receptor tyrosine kinase inhibitor, on recurrent pelvic adhesion formation after pelvic adhesiolysis in a rabbit model. Materials and methods A total of 20 New Zealand white rabbits underwent a uterine abrasion procedure, followed by an adhesiolysis procedure 4 weeks later. Before adhesiolysis, the rabbits were randomized to sunitinib at 10 mg/kg/d or placebo. These were administered as 1 dose preoperatively followed by 10 doses postoperatively. The rabbits were killed 30 d after the adhesiolysis procedure. At death, the adhesions were scored, and a total adhesion score (presented as the median and interquartile range [IQR]) was calculated according to the percentage of uterine involvement and the tenacity of the adhesions. Results All the rabbits survived the operative procedures without complications. The sunitinib-treated rabbits (n = 10) had a significantly lower uterine involvement score (median 2.0, IQR 1.0–3.0) than the placebo-treated rabbits (median 4.0, IQR 3.0–4.0; P = 0.02). The sunitinib-treated rabbits also had median tenacity score of 3.0 (IQR 3.0–4.0) compared with a median of 4.0 (IQR 4.0–4.0; P = 0.04) in the placebo-treated rabbits (n = 10). The median total score in the sunitinib-treated rabbits was 5.0 (IQR 4.0–6.25) compared with 8.0 (IQR 6.75, 8.0) in the placebo-treated rabbits (P = 0.01). Conclusions Sunitinib treatment might be an efficacious strategy to reduce recurrent adhesion formation after pelvic procedures.

Purpose The aim of this study was to determine the incidence of cholestasis and the correlation between cholestasis and weight-for-age z scores in parenteral nutrition–dependent neonates with gastroschisis. Methods A single-center retrospective review of 59 infants born with gastroschisis from January 2000 to June 2007 was conducted. Demographic and clinical data were collected and analyzed. Subjects were divided into cholestatic and noncholestatic groups. Statistical analyses included the Student t test, Wilcoxon rank sum test, Fisher exact test, and a general linear model. Results Fifty-nine neonates with gastroschisis were identified, and 16 (28%) of 58 patients developed cholestasis. Younger gestational age and cholestasis were found to be independently associated with weight-for-age z score in 30 of 58 patients with available long-term follow-up data. Conclusions Parenteral nutrition–dependent neonates with gastroschisis remain at considerable risk for the development of cholestasis. Both gestational age and cholestasis were found to be independent risk factors, predisposing these neonates to poor postnatal growth.

Purpose This study compares postoperative markers of liver injury in patients receiving intravenous fish oil (IFO) with parenteral nutrition (PN)–associated cholestasis (PNAC) to patients with resolved PNAC. Methods A retrospective review of all cholestatic-IFO patients undergoing abdominal laparotomy between March 1, 2007, and July 1, 2009, led to inclusion of 23 patients who collectively underwent 27 abdominal operations (13 pre-PNAC resolution and 14 post-PNAC resolution). Direct bilirubin (DB), total bilirubin, and alanine aminotransferase levels were examined over time in relation to operations. The time to resume presurgical trend of decreasing DB was calculated. Results Sixty-nine percent (9/13) of pre-PNAC resolution procedures were associated with postoperative increase in DB compared with 7% (1/14) of post-PNAC resolution procedures associated with a recurrence of cholestasis ( P = .02; odds ratio, 29.3; 95% confidence interval, 2.79-306.8). The median time to return to the preoperative downward trend of DB was 21 days. Conclusions Operations before PNAC resolution may be associated with an increased postoperative DB, possibly reflecting an exacerbation of liver injury. Operations post-PNAC resolution on IFO had a comparatively low incidence of postoperative cholestasis recurrence. Excepting clinical indication otherwise, it may be advisable to delay surgical intervention in the setting of PNAC in certain cases.

The step-by-step development in the production of HDT580X hot-rolled dual-phase steel (according to the EN 10338 standard) by means of the 2000 broad-strip hot-rolling mill at OAO Novolipetskii Metallurgicheskii Kombinat is considered. The analysis is based on theoretical and experimental results regarding topics such as the influence of alloying elements and the cooling parameters on structural and phase transformations in dual-phase steel for the auto industry. Physical modeling of the deformational parameters and the rolling and cooling temperatures and speeds on the broad-strip mill also proves helpful. Rolling and cooling rates are proposed for the 140 FGA semicontinuous hot-rolling mill.

Small-scale self-focusing is the main cause of power limitation in nanosecond Nd:glass lasers. We report pioneer observation in experiment of laser beam noise amplification for B -integral (nonlinear phase) order of unity, i.e., without destruction of nonlinear medium. Analytical dependences of noise amplification coefficient on the B-integral have been obtained for one nonlinear medium as well as for two nonlinear media separated by an air gap with image relay. A simple analytical dependence has been found for an optimal distance between two nonlinear media for which the maximum allowable value of B -integral increases from 2.7 to 4.3. The maximum attainable energy in neodymium-phosphate glass lasers with rod amplifiers 10 cm in diameter is 400 J with a pulse duration of 1 ns.

The critical energy of thermal self-action in a number of optical glasses made in Russia is measured. It is emphasized that one should take into account the effect of thermoelastic stress when calculating this energy.

A computer-aided autocollimator for measuring small angular deviations is described. Small angular displacements are determined by the displacement of the laser beam image on a CCD array in the focal plane of a lens. Automatic control of the displacement systems allows one to test many times the systems of precision remote displacement of optical components with a minimum detectable angular deviations of about 0.2″.

The transformation of the brightness of radiation with a complicated spatial structure in the process of efficient multiplication of the frequency is studied with the help of the method of moments. It is shown that the distortion of the wave front owing to the nonlinearity of the refractive index limits the brightness of laser systems with frequency doubling even before the development of fine-scale self-focusing.