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With alcohol and cannabis remaining the most commonly detected drugs in seriously and fatally injured drivers, there is a need to understand their combined effects on driving. The present study examined the effects of combinations of smoked cannabis (12.5% THC) and alcohol (target BrAC 0.08%) on simulated driving performance, subjective drug effects, cardiovascular measures, and self-reported perception of driving ability. In this within-subjects, double-blind, double-dummy, placebo-controlled, randomized clinical trial, cannabis users (1–7 days/week) aged 19–29 years attended four drug administration sessions in which simulated driving, subjective effects, cardiovascular measures, and whole blood THC and metabolite concentrations were assessed following placebo alcohol and placebo cannabis (

The conclusion of the Expert Council reports an agreement on the place of the P2Y 12 receptor blocker prasugrel in the early invasive treatment of patients with acute coronary syndrome ACS, according to the results of the multicenter randomized controlled study ISAR-REACT 5. Prasugrel should be considered the preferred P2Y 12 receptor blocker in the planned primary percutaneous coronary intervention and early invasive management of patients with ST segment elevation ACS. Herewith, prasugrel intake in patients with non-ST segment elevation ACS is preferable after coronary angiography and decision for coronary stenting.

The technique and results of the study of optical and microphysical characteristics of contrails with the use of the unique high-altitude polarization lidar of the National Research Tomsk State University are described. The microstructure parameters of ensembles of crystalline particles were estimated by comparing elements of light backscattering matrices calculated theoretically and obtained experimentally. It is shown that the condensation trail appearing in the atmosphere behind the plane 30–40 min after the emission of fuel combustion products from the engines consists of small chaotically oriented ice particles, mostly of the column shape.

Results of the complex lidar and actinometric studies of the characteristics of cirrus containing crystalline ice particles are discussed. The greatest attention is paid to clouds consisting of horizontally oriented ensembles of ice crystals. Orientation of the crystalline particles in clouds is estimated from the backscattering phase matrix, which is determined based on the data obtained with the polarization lidar directed vertically to the zenith. Solar radiation fluxes are measured using the standard methods with an actinometer and a pyranometer. It is shown that under certain weather conditions ice crystals at altitudes of cirrus formation can be oriented horizontally, which significantly affects the transmission of solar radiation.

Background Medications for smoking cessation are currently only effective in helping a minority of smokers quit. Drug development is slow and expensive; as such, there is much interest in optimizing the effectiveness of existing treatments and medications. Current standard doses of nicotine replacement therapy are not effective for many smokers, and in many cases, the amount of nicotine provided is much less than when a smoker is smoking their usual number of cigarettes. The proposed study will test if titrating the dose of the nicotine patch (up to 84 mg) will improve quitting success compared to those receiving a 21-mg nicotine patch with increasing doses of placebo patch. Methods This is a multicenter, pragmatic, two-arm, placebo-controlled, block randomized controlled trial. We will recruit participants who smoke at least 10 cigarettes daily and are interested in making a quit attempt. After 2 weeks of usual treatment with a 21-mg patch, participants who fail to quit smoking (target n = 400) will be randomized to receive escalating doses of a nicotine patch vs matching placebo patches for an additional 10 weeks or up to a maximum dose of 84 mg per day. Those who stop smoking during the first 2 weeks of usual treatment will continue with 21 mg patch treatment for 10 weeks and will form an additional comparison arm. In addition to the medication, participants will receive brief behavioral counseling at each study visit. The primary outcome will be biochemically confirmed continuous abstinence from smoking during the last 4 weeks of treatment (weeks 9 to 12). Discussion Research evidence supporting the effectiveness of personalized doses of nicotine replacement therapy could change current practice in a variety of healthcare settings. Given the evidence that quitting smoking at any age diminishes the risk of tobacco-related morbidity and mortality, even small increases in absolute quit rates can have a substantial population-level impact on reducing smoking-related disease, mortality rates, and associated healthcare costs. Trial registration ClinicalTrials.gov, NCT03000387. Registered on 22 December 2016.

Objectives The efficacy of brief interventions for cannabis use was assessed in a systematic review and meta-analyses. Methods Systematic searches in academic databases were conducted, and reference lists of included studies were reviewed. Randomized trials were included that compared brief interventions with minimal control interventions for improving cannabis-specific outcomes among participants recruited from healthcare settings. Mean differences (MDs) based on change-from-baseline measurements were pooled using random-effects meta-analyses, with stratification by short term (≤3 months) and long term (>3 months). Results Ten reports from 9 studies were included. Most studies were conducted in the United States, including participants who were adults and were recruited from primary care or emergency departments. There were no significant effects of brief interventions on cannabis-specific Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) scores in the short term (MD -1.27 points; 95% confidence interval [CI] -3.75, 1.21; I 84.40%). The null pattern of findings was also observed for number of days of cannabis use in the past 30 days in the short term (MD -0.22 days; 95% CI -2.27, 1.82; I 60.30%) and long term (MD -0.28 days; 95% CI -2.42, 1.86; I 60.50%). The evidence base for other outcomes not subjected to meta-analyses was limited and mixed. Conclusions Brief interventions did not result in reductions in cannabis-specific ASSIST scores or number of days of cannabis use, whereas the evidence base for other outcomes was limited and mixed. As such, brief interventions in healthcare settings may not be efficacious for cannabis use.

Background In 2013, an Integrated Care Pathway (ICP) for concurrent Major Depressive (MDD) and Alcohol Use (AUD) Disorders was developed at the Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada. The ICP was further implemented at 8 other clinical sites across Ontario (the DA VINCI Project) in 2015–2017. The goal of this study was to systematically describe and analyze the main clinical outcomes of the project. Methods Data on a non-randomized cohort of patients receiving ICP-based treatment were collected prospectively at nine clinical sites in a variety of clinical settings. Statistical methods: descriptive statistics, t-test, chi-square, ANOVA, generalized linear models. Results Two hundred forty-six patients were enrolled, 58.8% males, mean age was 45.6 years, 170 patients received treatment at academic health centres (AHC), 49 – at community hospitals (CH) and 27 – in family health teams (FHT). There were no major differences in anamnestic parameters and depression severity between the three settings, but there were differences in baseline drinking patterns between subgroups (F = 4.271, df = 2, p = 0.015). Overall completion rate was 70.7% with no significant variation between settings (χ2 = 3.35, df = 2, p = 0.19). Treatment duration in AHC was the longest, and completion rates were the highest. There was a statistically significant and clinically meaningful reduction in the number of drinking days per week (1.81, t = 8.78, p

Background and Objectives Patients with opioid use disorders and mood and anxiety symptoms have a variable prognosis. Few randomized controlled trials (RCTs) have evaluated treatment of depression or anxiety in patients receiving opioid agonist therapies (OAT). This review evaluates studies of pharmacotherapy/psychotherapy for treating symptoms of depression or anxiety in patients receiving OAT. Methods Public databases were searched for clinical trials of pharmacotherapy or psychotherapy for managing depression or anxiety symptoms in adults receiving OAT. Subsequently, we conducted a random effects meta-analysis model of RCTs by antidepressants subclasses. Results In our literature search, we identified 22 RCTs, eight of which were eligible for meta-analysis. Seven studies evaluated antidepressants in patients already maintained on OAT; two studies reported significant results for antidepressant effects versus placebo. Similarly, two of the seven studies that initiated antidepressants with OAT had advantages over placebo. Meta-analysis of grouped data revealed that tricyclic antidepressants (TCAs) (n = 235) significantly improved mean depression scores (SMD = −2.35, 95%CI: [−4.35, −0.34], z = −2.29, p = .022) while Selective Serotonin Reuptake Inhibitors (SSRIs) (n = 311) were not significantly different than placebo (SMD = 0.47, 95%CI: [−0.35, 1.30], z = 1.12, p = .263). Four out of five studies that implemented psychotherapeutic approaches reported a greater reduction of depressive symptoms than the comparison group. (Am J Addict 2017;XX:XX–XX) Conclusions and Scientific Significance To date, psychotherapy has the most documented evidence for efficacy. TCAs appears effective but with more adverse effects than SSRIs. Further studies of OAT and adjunct antidepressant treatments for dual diagnosis patients are warranted. (Am J Addict 2017;XX:1-13)

Background Major Depressive Disorder (MDD) and Alcohol Use Disorder (AUD) are highly prevalent, comorbid, and have significant impact on morbidity, mortality, and socioeconomic burden in Canada. Combined psycho- and pharmacotherapies for both conditions promise better outcomes than treatment as usual (TAU). At the Centre for Addiction and Mental Health, Toronto, Canada, we developed and implemented an Integrated Care Pathway (ICP) specifically for treatment of concurrent MDD and AUD. The goal of the study is to assess the clinical effectiveness of the ICP approach in comparison to TAU. Materials and Methods Non-randomized design, clinical chart review, Chi-square and t-tests, Cohen's d, Linear Mixed Effects Models, Kaplan–Meier, and log-rank analyses. Results Eighty-one ICP patients were included, matched to 81 controls by age, sex, severity of depressive symptoms, and patterns of drinking. ICP cohort had a significantly lower dropout rate (18.5% vs 69.1%, p

Differential optical absorption spectroscopy (DOAS) gas-analyzer was successfully tested. Ultraviolet light emitting diodes and high pressure Xe arc lamp were employed as a light sources. Recent developments in fibre-coupling telescope technology and the availability of UV LEDs allowed us to construct a portable instrument. The DOAS system consisted of a coaxial telescope, a spectrometer, and retroreflector. Gas analyzer spectral data bank includes more than 40 molecules absorbed in UV spectral region. Minimally detected concentration is the unit of ppb on paths up to 500 m. The results of the field test measurements of pollutants in Tomsk are presented

Optical models of high-level clouds (HLCs) used for calculation of radiation fluxes in the atmosphere are analyzed briefly. Results of the experiments on polarization laser sensing of cirrus performed with the lidar developed at the National Research Tomsk State University are described. Optical and microphysical characteristics of such clouds obtained from the results of measurements of their entire backscattering phase matrices are presented. It is shown that the orientation of crystals in the cirrus significantly affects the transmission of shortwave solar radiation. This fact proves incorrectness of the representation of real crystalline particles in HLCs with spherical particles with the corresponding effective radii during calculating the Earth’s radiation budget.

Results of the experiments on polarization laser sensing of aircraft contrails performed with the lidar developed at the National Research Tomsk State University are described. The altitudes of the lower and upper borders, backscattering phase matrices, optical thickness, and scattering ratios of the observed aerosol formations are determined. Microstructure parameters of the contrails are estimated by comparing the elements of backscattering phase matrices not only obtained from lidar experiments, but also calculated theoretically. The meteorological conditions for the formation of the preferred horizontal spatial orientation of ice crystals in contrails are established.

Background Clinical decision support systems (CDSSs) may promote practitioner adherence to evidence-based guidelines. This study examined if the addition of a CDSS influenced practitioner delivery of a brief intervention with treatment-seeking smokers who were drinking above recommended alcohol consumption guidelines, compared with practitioners who do not receive a CDSS prompt. Methods This was a cluster randomized controlled trial conducted in primary health care clinics across Ontario, Canada, implementing the Smoking Treatment for Ontario Patients (STOP) smoking cessation program. Clinics randomized to the intervention group received a prompt when a patient reported consuming alcohol above the Canadian Cancer Society (CCS) guidelines; the control group did not receive computer alerts. The primary outcome was an offer of an appropriate educational alcohol resource, an alcohol reduction workbook for patients drinking above the CCS guidelines, and an abstinence workbook to patients scoring above 20 points in the AUDIT screening tool; the secondary outcome was patient acceptance of the resource. The tertiary outcome was patient abstinence from smoking, and alcohol consumption within CCS guidelines, at 6-month follow-up. Results were analyzed using a generalized estimation approach for fitting logistic regression using a population-averaged method. Results Two hundred and twenty-one clinics across Ontario were randomized for this study; 110 to the intervention arm and 111 to the control arm. From the 15,222 patients that enrolled in the smoking cessation program, 15,150 (99.6% of patients) were screened for alcohol use and 5715 patients were identified as drinking above the CCS guidelines. No statistically significant difference between groups was seen in practitioner offer of an educational alcohol resource to appropriate patients (OR = 1.19, 95% CI 0.88–1.64, p = 0.261) or in patient abstinence from smoking and drinking within the CCS guidelines at 6-month follow-up (OR = 0.93, 95% CI 0.71–1.22, p = 0.594). However, a significantly greater proportion of patients in the intervention group accepted the alcohol resource offered to them by their practitioner (OR = 1.48, 95% CI 1.01–2.16, p = 0.045). Conclusion A CDSS may not increase the likelihood of practitioners offering an educational alcohol resource, though it may have influenced patients’ acceptance of the resource. Trial registration This trial is registered with ClinicalTrials.gov, number NCT03108144, registered on April 11, 2017, “retrospectively registered”. Electronic supplementary material The online version of this article (10.1186/s13012-019-0935-x) contains supplementary material, which is available to authorized users.

Randomized clinical trials have established the efficacy of naltrexone for reducing quantity of alcohol consumption and incidence of relapse to heavy drinking. To evaluate putative treatment mechanisms, human laboratory studies have examined naltrexone's effects on alcohol responses and self-administration during short-term medication protocols. RESULTS from these studies are inconsistent and have yet to be examined in aggregate. This meta-analysis aimed to quantify naltrexone's effects on alcohol self-administration and craving in the context of placebo-controlled human laboratory trials. Potential moderators of medication effects were also examined. Meta-analyses of alcohol self-administration (k = 9, N = 490) and craving (k = 16, N = 748) confirmed that, under controlled experimental conditions, naltrexone reduces the quantity of consumption (Hedges' g = -.277, SE = .074, 95 percent CI = -.421, -.133, p © 2016 Society for the Study of Addiction. Language: en

Quad copter drone usually uses Brushless Direct Current (BLDC) motor as rotor due to high efficiency and small volume. The BLDC motor speed control is very important for drone position and velocity determent. The optical sensor can be used to measure the rotation speed of BLDC motor when tested in the laboratory. The calculation of rotation speed, use of Pulse Width Modulation (PWM) technique for speed control and serial interface can be implemented using a microcontroller. The purpose of this research is to control the speed of BLDC motor for ground test of drone rotor. From the measurements, the relation between speed reference signal controlled by PWM and actual speed are not linear due to time constant and fan load. The increase of PWM duty cycle produces the increase of motor speed. The regulating characteristics of motor can be used for speed control correction.

In the paper the analyses of the lidar measurements data of optical parameters of the cirrus clouds over the Tomsk city are presented. The valuation of the microphysical properties of the cirrus clouds was done by the backscattering matrices that were measured by the high-altitude polarization lidar (wavelength is 0.532 μm) from National Research Tomsk State University in 2016-2018. For the interpretation of the laser sensing data we used the backscattering matrices database designed in V.E. Zuev Institute of Atmospheric Optics, Russian Academy of Sciences, Siberian Branch. An attempt to interpret the measured matrix using the quasi-horizontal orientated hexagonal columns with the 1000 μm modal size Lmod is incorrect in view of the fact that the particles with this size are very unlikely in existence of nature. It was demonstrated that the calculated backscattering matrices together with proposed algorithm could be used for the valuation of microphysical properties of the measured backscattering matrices.

In the present report, results of the experiment on polarization laser sensing of contrails performed for one and a half days are discussed. The altitudes of boundaries of the aerosol layers, their backscattering matrices, optical thicknesses, and scattering ratios are determined. The vertical profiles of lidar returns are analyzed. The results are compared with the meteorological data at the altitudes of formation of high-level clouds.

High strength or construction bloating clay is widely used in construction operations especially in construction of roads, bridges, airfield pavement. It replaces crushed stone as an aggregate. Technology of high strength bloating clay requires essential changes in its stoving curve in comparison with the production of light bloating clay. It is shown that in order to solve an urgent construction problem of bloating clay release it is necessary to conduct monitoring of temperature pattern in a rotary kiln in several distinctive cross sections and conduct management of a kiln as an object with distributed constants with the use of several, especially three, concentrated control actions. The developed mathematical model of stoving process and methodology of computing experiment, exemplified by the 40×2,5м kiln, allowed to find operating areas of condition and management of an automated object, focused on bloating clay release with assigned strength.

The mechanisms of individual vortex pinning and stability of multivortex configurations in different super-conducting compounds and artificial structures are analyzed on the basis of microscopic theory, which allowed describing the corresponding modification of the anomalous spectral branches in the quasiparticle spectrum caused by the electron scattering at the defect. The individual pinning potentials and corresponding depinning currents are evaluated. The experimentally observable consequences for the scanning tunneling microscopy characteristics and high-frequency field response are discussed. The comparative study of the conventional and chiral superconductors allowed suggesting experimental tests probing the superconducting gap symmetry. The chiral superconductors are shown to reveal a strong dependence of the pinning characteristics on the mutual orientation of the magnetic field and internal angular momentum of the Cooper pair.

A differential optical absorption spectroscopy (DOAS) gas-analyzer was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source. This system consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector. In order to record the spectra, a monochrometer with a grating and photodiode array was adopted. Gas analyzer spectral data bank includes more than 30 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares to determine the average mixing ratio of each species in the atmosphere. A number of air pollutants concentrations: SO2, NO2, O3, etc were trace measured. Minimally detected concentration on pathlength 400 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk are presented.

The amount of energy consumed by a heating system is significantly influenced by the number of radiator sections and the temperature at the forward feeder. Changing the number of radiator sections affects the amount of emitted heat energy and, consequently, the temperature of the heat conductor on the return-line. This article describes the prototype of an expert system providing an optimal design of the heating circuit. This system is designed to perform an automatic search of optimal energy consumption based in its turn on two parameters: the number of radiator sections and the temperature at the forward feeder.

Results of experiments on polarization laser sensing of high-level clouds performed at the high-altitude polarization lidar developed at National Research Tomsk State University are discussed. It is shown that orientation of crystalline ice particles in a cloud leads to different values of the measured depolarization ratio for the same cloud, which depends significantly on the azimuthal orientation of the polarization plane of sensing radiation.

This paper presents the mathematical description of cascade control servo system of the feed drive. A neural network controller is developed in MATLAB/Simulink environment. The comparison between neural network controller and the traditional P-controller is discussed.

This article discusses the method of indirect measurement of speed based on the information received from the rotor position sensor. The method is to implement numerical differentiation using polynomial interpolation. The paper evaluated the accuracy and speed of the method of polynomial interpolation. Speed is defined for modern 32-bit microcontrollers Microchip dsPIC33F and Atmel AVR32UC.

Data of polarization laser sensing of high-level clouds obtained within the year from April, 2011 are processed. Attention is focused on cirrus clouds with anomalous reflection. The optical thickness and average extinction coefficient of cirrus clouds comprising horizontally oriented crystals are estimated for sensing radiation with different polarization states.

Although the fact that lidars are used more than half a century, so many of the technical and methodological problem of the laser sensing has not been resolved. Laser sensing of optically dense aerosol formations (such as clouds or fog) belongs to the need of careful study. This is because the lidar signal from such formations is due not only single, but also multiple scattering, which significantly affects both the intensity value and the state of polarization of the received radiation. We have obtained an analytical expression for the time delay of the lidar return from the cloud layer due to multiple scattering. It is shown that the value of this lidar return is determined by the lower boundary, the microstructure and the thickness of the cloud layer, and a field-of-view of lidar receiving system.

An active differential optical absorption spectroscopy (DOAS) gas-analyzer was successfully tested. The DOAS system consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector. A high pressure 150-W Xe arc lamp and UV LEDs were employed as a light source. In order to record the spectra, a monochrometer with a grating and photodiode array was adopted. Gas analyzer spectral data bank includes more than 40 molecules absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. As a result of experiments time series of concentrations of gases polluting the atmosphere were trace measured. Minimally detected concentration is the unit of ppb on path length from 200 to 500 m at the time of accumulation up to 3 minute. The results of the field test measurements of pollutants in Tomsk are presented.

Joint analysis of the data on polarization laser sensing of cirrus obtained using the ground based polarization laser developed at National Research Tomsk State University (Russia, Tomsk) with the results of theoretical calculations is described. The possibility of estimation of the microstructure parameters of cirrus with a preferred orientation of ice crystals on the basis of comparison of the backscattering phase matrices obtained experimentally and calculated theoretically is discussed.

The method of field weakening, which provides constant power at a constant current, is examined. This method is based on maintaining constant steady-state values for projections of stator current on the longitudinal and transverse axes of a synchronous motor. The projection of stator voltage on the longitudinal axis remains unchanged, but the projection of stator voltage on the transverse axis depends on speed. To assess the effectiveness of this method, a mathematical model of the electric drive was developed with vector control and a field-weakening module. From this model of the working of the electric drive, the mechanical characteristics and dependence of efficiency on the speed of the motor were established using the program Simulink.

This work was supported by the Russian Foundation for Basic Research, project no. 10-03-96043-r_Urals_a. Temperature dependencies of density (by the gamma-penetrating method), electrical resistivity (by the contact-less method in rotating magnetic field), and magnetic susceptibility (by the Faraday method) of Sn-Bi alloys with near-eutectic compositions are investigated. The alloy with eutectic composition, Sn -58% (mass) Bi, is shown to differ significantly in the electron structure from hypo- and hypereutectic ones. The melt overheating above the given temperature provides the hysteresis of the properties sensitive to electron structure.

In course of the search for the optical identifications associated with ROSAT X-ray sources we have found a highly variable object with the very unusual long-term behavior, color indices and high X-ray-to-optical flux ratio. We report the archival photometric light curve from the Catalina Sky Survey, optical spectroscopy from RTT150 and time-resolved photometry from Astrotel-Caucasus telescope. The object appears to be the magnetic cataclysmic variable (polar) with orbital period of P=3.20 hr., 8 pages, 5 figures. Submitted to Astronomy Letters

Interpretation of data of atmospheric laser sensing is based on the lidar equation valid for single scattering. However, investigations of dense aerosol formations call for consideration of multiple scattering. In the present paper, a method of correcting the light backscattering phase matrix (BSPM) measured in cloud depth, where the lidar signal is formed not only by single scattering but also by multiple scattering, is discussed. A data correction algorithm is based on the property of BSPM symmetry, double scattering approximation for lidar return description, and simplified polarized radiation transfer equations for anisotropic scattering media used to calculate the depolarization profile of lidar response from cloud depth. Results of calculating the polarization degree of double scattering lidar returns from homogeneous clouds are presented. The possibility of reconstructing the microstructure parameters for water-drop and crystal clouds from the polarization degree of double scattering lidar return by means of changing the polarization state of sensing radiation is demonstrated.

A technique for determining the microstructure parameters of high-level clouds on the basis of joint analysis of experimental and theoretical data is described. Results of the experiments on atmosphere laser sensing and theoretical calculations of light scattering by spatially oriented ice crystals are shown.

Methodology for determination of the optical and geometric characteristics of clouds is described. Problems of processing data obtained in experiments on polarization laser sensing of the atmosphere are discussed. Technique for reduction of the phase matrices of cirrus obtained with the high-altitude polarization lidar developed at National Research Tomsk State University to the symmetry plane affixed to the preferred orientation of ice crystals in cirrus is described. The experimental data are compared with the data of numerical modeling of phase matrices in the physical optics approximation and meteorological conditions over the lidar at cirrus altitudes. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

We study the thermodynamics of the diffusive SFS trilayer composed of thin superconductor (S) and ferromagnet (F) layers. On the basis the self-consistent solutions of nonlinear Usadel equations in the F and S layers we obtain the Ginzburg--Landau expansion and compute the condensation free energy and entropy of the $0$ (even) and $\pi$ (odd) order parameter configurations. The first order $0-\pi$ transition as a function of temperature $T$ occurs, which is responsible for a jump of the averaged magnetic field penetration depth $\lambda(T)$ recently observed on experiments [N.Pompeo, et. al., Phys. Rev. B 90, 064510 (2014)]. The generalized Ginzburg-Landau functional was proposed to describe SFS trilayer for arbitrary phase difference between the superconducting order parameters in the S layers. The temperature dependence of the SFS Josephson junction critical current demonstrates the strong anharmonicity of the corresponding current--phase relation in the vicinity of the $0-\pi$ transition. In rf SQUID, coexistence of stable and metastable $0$ and $\pi$ states provides integer and half--integer fluxoid configurations., Comment: 11 pages, 9 figures

A differential optical absorption spectroscopy (DOAS) gas-analyzer was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source This system consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector. In order to record the spectra, a monochrometer with a grating and photodiode array was adopted. Gas analyzer spectral data bank includes more than 30 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. A number of air pollutants concentrations: SO2, NO2, O3, etc were trace measured. Minimally detected concentration on pathlength 400 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk are presented.

According to the model of the effective medium and G. Mie theory, attenuation cross-sections, cross-sections for scattering and absorption for metal nanoparticles nanosized aggregates have been assessed depending on the aggregate’s size , level of the aggregate’s filling with nanoparticles and physical properties of the nanoparticles material.

The task of laser sensing of droplet clouds by coaxial lidar is considered. Lidar return due to single scattering is formed in the volume bounded by the radiation pattern of the transmitter, while the double-scattering is determined by a receiving system field of view. The volume of the scattering medium exceeding a receiving system field of view forms the signal higher scattering orders ( > 2). The results of the numerical modeling of the distribution (in the recording plane) polarization characteristics of lidar signal from droplet clouds in the double scattering approximation in comparison with the results of the physical model experiment simulating sounding of a droplet cloud are discussed in this paper.

Experimental results of polarization laser sensing of cirrus with anomalous backscattering are presented. The technique of determining the optical and geometrical characteristics of clouds is described. Experimental data are compared with the meteorological conditions at altitudes of cirrus above the lidar location and with the results of numerical modeling of phase matrices in the approximation of physical optics. The recurrence frequency of meteorological characteristics of “mirror” cirrus is estimated.

The paper focuses on retrieving the microphysical characteristics of cirrus clouds from lidar data. The beam-splitting algorithm developed by the authors within framework of physical optics approximation has been used to solve the problem of light scattering by the hexagonal ice crystals. The paper presents the color ratio, depolarization ratio, and lidar ratio that have been calculated for the first time for quasi-horizontally and randomly oriented hexagonal ice particles. The lidar experimental data measuring simultaneously the depolarization ratio and color ratio in cirrus clouds are also presented.

The given work is devoted to a problem of numerical simulation and analysis of the vertical cavity lasers parameters with the purpose of numerical simulation methods improving. The analysis of the VCSEL with the help of the mathematical model, based on beam propagation method, are presented. The dependence of the VCSEL dynamic behavior on the temperature dependence of the gain coefficient is submitted. With the help of extended system of the rate equations for VCSEL the modulation characteristics are obtained. Analysis of the lasing wavelength dependence on thermal gain coefficient is carried out.

Several physical factors that govern the light scattering scenario in optically anisotropic media are discussed and the degree to which they may affect the date of laser sounding of crystal clouds is assessed. Among the peculiarities of light propagation and scattering in such media there are: 1) possible changes in the state of polarization of a sounding beam; 2) the transformations of the polarization state and extinction of sounding radiation may depend on the direction of sounding; 3) the data of laser sounding regarding the backscatter and lidar depolarization may be ambiguous. The matter is that in an anisotropic medium these properties of the backscattered radiation depend on the polarization state of a sounding beam and on the orientation of the lidar. As the calculated and experimental data presented in this paper show, the change of the sounding beam polarization state during the propagation in cirrus clouds may be neglected in the majority of practical cases. At the same time, the dependence of the radiation extinction on the direction of sounding, as well as the ambiguity in sounding data mentioned above should certainly be taken into account.

A polarization backscattering phase matrix for oriented semitransparent plates is given in the present paper. The matrix elements have been numerically investigated. Regular dependences have been established of the matrix elements on the orientation angle of particles with respect to the sensing direction, the orientation angle of the polarization plane, and the refractive index of particles. An algorithm has been developed for determining the refractive index and the orientation angle of ice plates from the data of polarization lidar sensing for two-angle sensing geometry. A formula has been derived that relates the main parameters of the medium with the backscattering coefficient that can be used for interpretation of highly intense lidar return signal.

The operation of an airborne lidar intended for the detection of fish schools is numerically simulated by the Monte Carlo method. The calculations are performed for schools located at small depths in order to study the regularities in the shaping of the lidar return accurately. Three models of the phase function of scattering of laser radiation in sea water are used. The signals reflected from surface waters that contain a school of fish are determined as a function of the lidar parameters, light scattering and absorption coefficients in the water, stratification of light scattering layers, and fish-school depth. The results obtained can be used for interpreting the signals of the fish-detection lidar.

An equation is obtained for the Stokes vector of radiation twice scattered in the backwards direction, assuming that the transmitter and receiver have small angular apertures, that the pulse length is short, and that the receiver and the transmitter are monostatically placed.

The absorption of laser radiation at a wavelength of 694.38 nm is estimated. Various spectral widths of the pulses probing the atmosphere are considered. Questions related to the interpretation of the data obtained from laser probing of the water vapor concentration along the horizontal and vertical directions in the atmosphere are discussed. The effect of a shift of the center of the emission line with respect to the center of the absorption line on the error of the reconstructed profile of the absorbing gas is estimated. The possible use of the shape of the water vapor absorption line for probing purposes is studied.

An approximate solution is given for the temperature distribution in a porous body bearing a flow of cooling agent which undergoes a phase transition.