Simulation of production processes at aircraft building enterprises

The effective development of productive capacities of the domestic aircraft industry was analyzed. A methodology for calculating general indicators for assessing the feasibility of production programs of the aviation industry at the level of technological limits and types of aircraft manufacturing was developed. The application of this methodology will allow making more meaningful determination of the material consumption of new types of aviation products and the productivity of new equipment and ultimately assessing the feasibility of prospective production plans. Monitoring of the performance indicators of the domestic aircraft industry will give new impetus to research in the sphere of development, production and maintenance of science-intensive products according to their specificity. Despite the great value of scientific studies of the works of many scientists in the sphere of organization of production at enterprises, there are currently unresolved issues of an industrial and technological nature

The existence of a real pole-free solution of the fourth order analogue of the Painleve I equation

We establish the existence of a real solution y(x,T) with no poles on the real line of the following fourth order analogue of the Painleve I equation, x=Ty-({1/6}y^3+{1/24}(y_x^2+2yy_{xx})+{1/240}y_{xxxx}). This proves the existence part of a conjecture posed by Dubrovin. We obtain our result by proving the solvability of an associated Riemann-Hilbert problem through the approach of a vanishing lemma. In addition, by applying the Deift/Zhou steepest-descent method to this Riemann-Hilbert problem, we obtain the asymptotics for y(x,T) as x\to\pm\infty.Comment: 27 pages, 5 figure

Formation of nanoislands on the surface of thin dipeptide films under the effect of vaporous organic compounds

Sorption properties of a thin L-alanyl-L-valine dipeptide film for vapors of organic compounds, i.e., methanol and toluene, were studied. Compositions of the inclusion compounds formed in the systems are determined using quartz microbalances. The surfaces morphology of of thin dipeptide films before and after the interaction with organic sorbate was studied with atomic force microscopy. The dipeptide was found to have a larger sorption capacity for methanol than for toluene. As a result of the interaction between a thin L-alanyl-Lvaline dipeptide layer with toluene vapor, nanoislets appear on the film surface, and the receptor ability of dipeptide inactivated. © Pleiades Publishing, Ltd., 2009

Metabolic Risk Factors and Their Impact on Quality of Life in Patients with Pancreatic Cancer, Acute or Exacerbated Chronic Pancreatitis

Аim: to evaluate metabolic risk factors and their impact on quality of life in patients with pancreatic cancer (PC) and in patients with acute or exacerbated chronic pancreatitis.Materials and methods. Forty-five patients with PC (group 1) and 141 patients with acute pancreatitis or exacerbated chronic pancreatitis (group 2) in an observational multicenter clinical cross-sectional uncontrolled study were examined. Clinical, laboratory and instrumental examination of patients and assessment of risk factors (lipid profile, blood plasma glucose, obesity, arterial hypertension) were carried out in accordance with clinical recommendations. Patients completed the SF-36 questionnaire once to assess quality of life at hospital admission before treatment.Results. In group 1, indicators of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) in blood serum (3.7 ± 0.2; 2.2 ± 0.2 and 0.8 ± 0.1 mmol/L) were lower than in group 2 (5.1 ± 0.1; 3.1 ± 0.1 and 1.2 ± 0.1 mmol/L; p < 0.05). Arterial hypertension was more common in group 1 (55.6 %) than in group 2 (34.8 %; p = 0.013). The presence of arterial hypertension increases the chance of having PC by 2.7 times (p < 0.05). Body mass index parameters, including obesity, as well as parameters of triglycerides, and fasting plasma glucose, did not differ between the groups. Logistic regression analysis revealed a direct relationship with PC HDL hypocholesterolemia (Exp B = 4.976; p < 0.001) and arterial hypertension (Exp B = 2.742; p = 0.027) and an inverse relationship — with hypercholesterolemia (Exp B = 0.204; p = 0.002). The chance of having PC was not associated with age, fasting plasma glucose ³ 7.0 mmol/L, obesity. Quality of life indicators were higher in group 1 than in group 2 on four SF-36 scales: bodily pain (68.1 ± 5.1 and 36.8 ± 2.0; p < 0.001), general health (51.1 ± 2.5 and 38.0 ± 1.7 points; p < 0.001), social functioning (74.7 ± 3.0 and 64.5 ± 2.2 points; p = 0.007), role emotional functioning (28.2 ± 5.2 and 12.5 ± 3.1 points; p = 0.007) and in the general domain “physical component of health” (40.2 ± 1.0 and 33.6 ± 0.8 points; p < 0.001). In group 1 with HDL hypocholesterolemia compared with its absence, the indicators of role emotional functioning (22.2 ± 5.1 and 51.9 ± 13.7 points; p = 0.020) were lower, with arterial hypertension compared with its absence — role physical functioning (5.0 ± 4.0 and 25.5 ± 7.5 points; p = 0.036) and role emotional functioning (16.0 ± 5.1 and 43.3 ± 8.8 points; p = 0.007) were lower.Conclusions. In patients with PC arterial hypertension was more common and the levels of total cholesterol, LDL-C and HDL-C were lower than in patients with acute or exacerbated chronic pancreatitis. The chance of having PC is directly associated with HDL hypocholesterolemia, with arterial hypertension, inversely — with hypercholesterolemia, and is not associated with age, fasting plasma glucose ³ 7 mmol/L, or obesity. In patients with PC, quality of life indicators were higher on four SF-36 scales and on the general domain “physical component of health” than in the group with acute or exacerbated chronic pancreatitis. In patients with PC metabolic factors significantly worsened self-assessment of quality of life in terms of role functioning; in patients with acute or exacerbated chronic pancreatitis there was no such association

Another look at the BL Lacertae flux and spectral variability

The GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT) monitored BL Lacertae in 2008-2009 at radio, near-IR, and optical frequencies. During this period, high-energy observations were performed by XMM-Newton, Swift, and Fermi. We analyse these data with particular attention to the calibration of Swift UV data, and apply a helical jet model to interpret the source broad-band variability. The GASP-WEBT observations show an optical flare in 2008 February-March, and oscillations of several tenths of mag on a few-day time scale afterwards. The radio flux is only mildly variable. The UV data from both XMM-Newton and Swift seem to confirm a UV excess that is likely caused by thermal emission from the accretion disc. The X-ray data from XMM-Newton indicate a strongly concave spectrum, as well as moderate flux variability on an hour time scale. The Swift X-ray data reveal fast (interday) flux changes, not correlated with those observed at lower energies. We compare the spectral energy distribution (SED) corresponding to the 2008 low-brightness state, which was characterised by a synchrotron dominance, to the 1997 outburst state, where the inverse-Compton emission was prevailing. A fit with an inhomogeneous helical jet model suggests that two synchrotron components are at work with their self inverse-Compton emission. Most likely, they represent the radiation from two distinct emitting regions in the jet. We show that the difference between the source SEDs in 2008 and 1997 can be explained in terms of pure geometrical variations. The outburst state occurred when the jet-emitting regions were better aligned with the line of sight, producing an increase of the Doppler beaming factor. Our analysis demonstrates that the jet geometry can play an extremely important role in the BL Lacertae flux and spectral variability.Comment: 12 pages, 10 figures, accepted for publication in A&

Familial adenomatosis of the colon: current state of the problem

The urgency of the problem of familial adenomatosis of the colon (FAC) is caused both by the severity of the disease with the inevitable development of cancer without timely treatment, and the involvement of the patient's blood relatives in this problem. Due to the rare incidence of this disease, many issues require discussion. Aim. To determine the possibility of timely treatment of FAC patients maintaining a satisfactory quality of life. Materials and methods. The data on 5 FAC patients and 12 their blood relatives were studied. Clinical, endoscopic and genetic characteristics of the disease and treatment were analyzed. Results. demonstrated that family history, genetic and endoscopic examinations allow diagnosis of FAC. Colectomy with rectal resection and the creation of a small intestine reservoir with reservoir-rectal anastomosis provide a sufficient quality of life for patients. Examination of the patient's blood relatives reveals new patients requiring additional examination and treatment. Conclusion. The problem of FAC is multidisciplinary and involves therapists, gastroenterologists, pediatricians, geneticists, endoscopists, radiologists, surgeons and oncologists. Only a timely diagnosis can help the patient to undergo radical treatment before the development of colon cancer

Long-term multi-wavelength variability and correlation study of Markarian 421 from 2007 to 2009

We study the multi-band variability and correlations of the TeV blazar Mrk 421 on year time scales, which can bring additional insight on the processes responsible for its broadband emission. We observed Mrk 421 in the very high energy (VHE) gamma-ray range with the Cherenkov telescope MAGIC-I from March 2007 to June 2009 for a total of 96 hours of effective time after quality cuts. The VHE flux variability is quantified with several methods, including the Bayesian Block algorithm, which is applied to data from Cherenkov telescopes for the first time. The 2.3 year long MAGIC light curve is complemented with data from the Swift/BAT and RXTE/ASM satellites and the KVA, GASP-WEBT, OVRO, and Mets\"ahovi telescopes from February 2007 to July 2009, allowing for an excellent characterisation of the multi-band variability and correlations over year time scales. Mrk 421 was found in different gamma-ray emission states during the 2.3 year long observation period. Flares and different levels of variability in the gamma-ray light curve could be identified with the Bayesian Block algorithm. The same behaviour of a quiet and active emission was found in the X-ray light curves measured by Swift/BAT and the RXTE/ASM, with a direct correlation in time. The behaviour of the optical light curve of GASP-WEBT and the radio light curves by OVRO and Mets\"ahovi are different as they show no coincident features with the higher energetic light curves and a less variable emission. The fractional variability is overall increasing with energy. The comparable variability in the X-ray and VHE bands and their direct correlation during both high- and low-activity periods spanning many months show that the electron populations radiating the X-ray and gamma-ray photons are either the same, as expected in the Synchrotron-Self-Compton mechanism, or at least strongly correlated, as expected in electromagnetic cascades.Comment: Corresponding authors: Ann-Kristin Overkemping ([email protected]), Marina Manganaro ([email protected]), Diego Tescaro ([email protected]), To be published in Astronomy&Astrophysics (A&A), 12 pages, 9 figure