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Spectral and light-current characteristics of lasers based on the asymmetric separate-confinement heterostructures InGaAs/InGaAsAl/InP and InGaAs/GaAs/AlGaAs/GaAs were studied in the pulsed mode of lasing. It is shown that, at high levels of current pumping, the charge-carrier concentration in the active region of semiconductor lasers for the near-infrared optical region increases beyond the oscillation threshold; drastic saturation of the light-current characteristics is observed. Processes occurring in lasers as the charge-carrier concentration increases beyond the lasing threshold are studied theoretically. It is established that, at high pump levels, the rate of stimulated recombination decreases, the lifetime of charge carriers increases, and both the concentration of emitted photons and the quantum yield of stimulated radiation decrease. It is shown that variations in stimulated recombination, the decrease in the quantum efficiency, and saturation of the light-current characteristic in semiconductor lasers at high levels of current pumping are caused by the contribution of the nonradiative Auger recombination.

Spectral and emission-power characteristics of semiconductor lasers based on quantum-dimensional asymmetric heterostructures with separate confinement in a system of InGaAs/GaAs/AlGaAs alloys are studied in the case of high pump levels in the pulsed mode of lasing (200 A, 100 ns, and 10 kHz). It is shown that, in lasers with a quantum-dimensional active region containing one or two levels of dimensional quantization, the spectrum consists of one or two lasing bands. It is established that the condition for inverse population of the second electron level and two-band lasing are attained due to leveling-off of the rate of stimulated recombination from the first electron level and a high density of states for the second level. It is shown that, in lasers with double-band lasing spectrum, the total emission spectrum exceeds appreciably the emission power of a laser with a single electron level and a single spectral band.

Spectral and light-current characteristics of separate-confinement lasers that are based on InAl-GaAs/InP and InGaAsP/InP alloys and emit in the wavelength range of 1.5–1.8 μm are studied at high excitation levels (up to 80 kA/cm2) in pulse operation (100 ns, 10 kHz). It is shown that the peak intensity in the stimulated-emission spectrum saturates as the pump current is increased. Further increase in the emitted power is attained owing to the emission-spectrum broadening to shorter wavelengths, similar to lasers on the GaAs substrates (λ = 1.04 μm). It is established experimentally that the broadening of the stimulated-emission spectrum to shorter wavelengths is caused by an increase in the threshold current and by an increase in the charge-carrier concentration in the active region. This concentration increases by a factor of 6–7 beyond the lasing threshold and can be as high as 1019 cm−3 in pulse operation. It is shown that saturation of the light-current characteristics in pulse operation takes place in the InAlGaAs/InP and InGaAsP/InP lasers as the pump current is increased. It is shown experimentally that there is a correlation between saturation of the light-current characteristic and an increase in the threshold current in the active region. An increase in the charge-carrier concentration and gradual filling of the active region and waveguide layers with electrons are observed as the pump current is increased; stimulated emission from the waveguide is observed at high pump currents.

We suggested and experimentally confirmed the effective method of internal optical loss reduction by high order mode suppression in a separate confinement quantum well laser heterostructure with asymmetric ultra thick waveguide. Manufacturing of InGaAs/GaAs/AlGaAs laser heterostructure with a 1.7 microm-thick asymmetric waveguide allowed attaining super low value of internal optical loss alphai=0.34 cm-1 preserving high efficiency and fundamental transverse mode operation. Record-high 16 W continuous wave (CW) and 145 W pulse room temperature front facet output optical power and 74% wallplug efficiency were attained in 100-microm-aperture 1.06-microm-emitting laser diodes with 3 mm cavity length.

Generation of a difference-frequency wave by two electromagnetic waves propagating in a heterolaser is analyzed theoretically. Calculations are carried out for InGaAs/GaAs/AlGaAs heterostructures of design optimized to attain maximum lasing power. It is shown that phase matching between the primary waves and the difference-frequency wave may persist over a distance of ∼1 mm, comparable to the cavity length (2–3 mm), and the conversion coefficient can be as large as several percent.

An immunodiagnostic lab-on-a-bead suspension microarray based on microbeads encoded with quantum dots (QDs) has been developed and preclinically validated for multiplexed quantitative detection of prostate cancer markers in human serum samples. The sensitivity and specificity of the microarray are similar to those of "gold-standard" single-analyte ELISA. Moreover, the array has an improved immunoassay capacity, ensures quantitative detection of multiple cancer biomarkers and may be operational in a considerably wider dynamic range of concentrations. The array is characterized by reduced time and cost of analysis and is compatible with classical flow cytometers. Proof-of-concept preclinical tests ensured simultaneous quantitative determination of free and total prostate-specific antigens in human serum, with clear discrimination between the control and clinical samples. The proposed approach is flexible and paves the way to development of a wide variety of immunodiagnostic assays for multiplexed early diagnosis of various diseases. From the Clinical Editor Early diagnosis of cancer can result in better prognosis for patients. Thus, the use of specific tumor markers is widely employed in clinical practice. Traditional screening methods only employ single markers. The authors here developed a microarray system based on microbeads encoded with quantum dots (QDs), which can be used for multiplexed quantitative detection. The validated results on patient samples should lead to the development of a wider variety of assays for other diseases.

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International audience; Multiplexed analysis of cancer markers is crucial for early tumor diagnosis and screening. We have designed lab-on-a-bead microarray for quantitative detection of three breast cancer markers in human serum. Quantum dots were used as bead-bound fluorescent tags for identifying each marker by means of flow cytometry. Antigen-specific beads reliably detected CA 15-3, CEA, and CA 125 in serum samples, providing clear discrimination between the samples with respect to the antigen levels. The novel microarray is advantageous over the routine single-analyte ones due to the simultaneous detection of various markers. Therefore the developed microarray is a promising tool for serum tumor marker profiling.

It is shown that the reason why the maximum attainable optical power in semiconductor lasers is limited is the finite time of carrier energy relaxation via scattering by nonequilibrium optical phonons in the quantum-well active region. The power and spectral characteristics of semiconductor lasers are studied experimentally at high excitation levels (up to 100 kA/cm2) in pulsed lasing mode (100 ns, 10 kHz). As the drive current increases, the maximum intensity of stimulated emission tends to a constant value (“saturates”), and the emitted power increases owing to extension of the spectrum to shorter wavelengths. The intensity saturation is due to limitation of the rate of stimulated recombination, caused by a finite time of the electron energy relaxation via scattering by polar optical phonons. It is found that the broadening of the stimulated emission spectrum is related to an increase in carrier concentration in the active region, which enhances the escape of electrons into the waveguide layers. As the drive current increases, the carrier concentration in the waveguide reaches its threshold value and there appears an effective channel of current leakage from the active region. The experiment shows that the appearance of a band of waveguide lasing correlates with a sharp drop in the differential quantum efficiency of a semiconductor laser.

Asymmetric GaInAs/GaInAsP/AlGaAs heterostructures with the emission wavelength of 940 and 980 nm were grown by MOCVD. The composition of solid solution in the waveguide layer, Ga0.74In0.26As0.47P0.53, was chosen based on the calculations of the escape energy of electrons from the quantum well of the active region into the waveguide. Semiconductor lasers with the emission aperture of 100 μm were fabricated from these heterostructures. The CW output optical power of 12 W was achieved at room temperature. The internal optical loss was 0.6 and 0.3 cm−1 for 940 and 980 nm wavelengths, respectively.

Asymmetric separate-confinement laser heterostructures with ultrawide waveguides based on AlGaAs/GaAs/InGaAs solid solutions, with an emission wavelength of ∼1080 nm, are grown by MOCVD. The optical and electrical properties of mesa-stripe lasers with a stripe width of ∼100 μm are studied. Lasers based on asymmetric heterostructures with ultrawide (>1 μm) waveguides demonstrate lasing in the fundamental transverse mode with an internal optical loss of as low as 0.34 cm−1. In laser diodes with a cavity length of more than 3 mm, the thermal resistance is reduced to 2°C/W, and the characteristic temperature T 0= 10°C is obtained in the range 0–100°C. A record-breaking wallplug efficiency of 74% and an output optical power of 16 W are reached in CW mode. Mean-time-between-failures testing for 1000 h at 65°C with an operation power of 3–4 W results in the power decreasing by 3–7%.

Internal optical loss in separate-confinement laser heterostructures with an ultrawide (>1 smm) waveguide has been studied theoretically and experimentally. It is found that an asymmetric position of the active region in an ultrawide waveguide reduces the optical confinement factor for higher-order modes and raises the threshold electron density for these modes by 10–20%. It is shown that broadening the waveguide to above 1 µm results in a reduction of the internal optical loss only in asymmetric separate-confinement laser heterostructures. The calculated internal optical loss reaches ∼0.2 cm−1 (for λ≈1.08 µm) in an asymmetric waveguide 4 µm thick. The minimum internal optical loss has a fundamental limitation, which is determined by the loss from scattering on free carriers at the transparency carrier density in the active region. An internal optical loss of 0.34 cm−1 was attained in asymmetric separate-confinement laser heterostructures with an ultrawide (1.7 µm) waveguide, produced by MOCVD. Lasing in the fundamental transverse mode has been obtained owing to the significant difference in the threshold densities for the fundamental mode and higher-order modes. The record-breaking CW output optical power of 16 W and wallplug efficiency of 72% is obtained in 100-µm aperture lasers with a Fabry-Perot cavity length of ∼3 mm on the basis of the heterostructures produced.

Internal optical loss in high-power semiconductor lasers based on quantum-well separate-confinement heterostructures was studied. Calculations show that the major portion of the internal optical loss occurs in the active region and emitters. Making the laser waveguide thicker and the cavity longer reduces the internal optical loss. Two possible approaches to the design of laser heterostructures are considered, and optimal solutions are suggested. The difference in the internal optical loss between lasers on InP and those on GaAs substrates is attributed to the larger cross section of photon absorption by holes in InP. Good agreement between the calculated and experimental values of the internal optical loss in lasers on InP and GaAs substrates is obtained.

Separate-confinement InGaAsP/InP heterostructures with highly strained quantum wells are grown by metal-organic vapor-phase epitaxy (MOVPE). The properties of InGaAsP and InGaAs quantum wells are studied, and the influence of the heterostructure parameters on the lasing wavelength is analyzed. The grown structures are used for designing high-intensity multimode and single-mode mesa-stripe laser diodes operating in the range λ=1.7–1.8 µm. The maximum continuous-wave lasing power achieved at room temperature is 1.6 W and 150 mW for multimode and single-mode laser diodes, respectively. Single-mode lasing is retained up to 100 mW.

The possibility of achieving maximal optical output power in the single-mode lasing for mesa-stripe laser diodes fabricated on the basis of InGaAsP/InP quantum-well heterostructures with separate confinement have been studied both experimentally and theoretically. The basic condition for the single-mode lasing of laser diodes in a wide range of driving currents is shown to be the precise choice of the effective refractive index ΔnL discontinuity in the plane parallel to the p-n junction. A InGaAsP/InP separate confinement heterostructure with a step waveguide, with a threshold current density of 180 A/cm2 and an internal quantum efficiency of stimulated emission of 93–99%, has been manufactured via the MOCVD method. The optimization of the mesa-stripe diode design for the developed InGaAsP/InP heterostructure is carried out with the aim of achieving maximal optical output power in the case of single-mode lasing. An output power of 185 mW is attained in the laser diode with the mesa-stripe width W=4.5 μm (λ=1480 nm). The maximal continuous output power was as high as 300 mW. The full width at half-maximum (FWHM) of the lateral far-field pattern increased by 1° relative to the threshold value.

Single-mode and multimode quantum well (QW) laser diodes with emission wavelengths λ=1.0 and 1.58 µm, based on MOCVD-grown separate-confinement heterostructures, have been studied. An analysis of the threshold current density and optical gain is made on the basis of experimental dependences of the threshold current and differential quantum efficiency on the cavity length. The threshold current is decomposed into principal components in terms of model approximations taking into account the Auger recombination, ejection of electrons from QWs into waveguide layers, and lateral current spreading to passive regions of a mesa-stripe laser.

Results of solar flare observations obtained in the Konus-Wind experiment from November, 1994 to December, 2013 and in the Helicon Coronas-F experiment during its operation from 2001 to 2005, are presented. For the periods indicated Konus-Wind detected in the trigger mode 834 solar flares, and Helicon-Coronas-F detected more than 300 solar flares. A description of the instruments and data processing techniques are given. As an example, the analysis of the spectral evolution of the flares SOL2012-11-08T02:19 (M 1.7) and SOL2002-03-10T01:34 (C5.1) is made with the Konus-Wind data and the flare SOL2003-10-26T06:11 (X1.2) is analyzed in the 2.223 MeV deuterium line with the Helicon-Coronas-F data., Comment: Published version. A list of the Konus-Wind solar flare triggers and figures of their time profiles are available at http://www.ioffe.ru/LEA/Solar/

A MOCVD technology for growth of InGaAs/GaAs/InGaP laser heterostructures on a modified Epiquip VP-50-RP installation was developed. Mesa stripe laser diodes with threshold current density Jth=100–200 A/cm2, internal optical loss αi=1.3–1.7 cm−1, and internal quantum efficiency ηi=60–70% have been fabricated. A CW output optical power of 5 W has been obtained for a single 100-µm-wide aperture mesa stripe laser diode emitting at 1.03 µm. It is shown that use of AlGaAs waveguide layers, which increase the conduction band barrier offset, lowers the temperature sensitivity of laser heterostructures within the temperature range 10–80°C.

Epitaxially stacked tunnel-junction laser hetero structures were grown by hydride metalorganic vapor-phase epitaxy in the system of AlGaAs/GaAs/In GaAs alloys. Based on such structures, mesa stripe lasers with an aperture of 150 s- 7 m were fabricated. The possibility of controlling the lasing wavelength by varying the active region thickness in each tunnel-junction laser structure was demonstrated. Independent two-band lasing at wavelengths of 914 and 925 nm (the difference frequency is 2.3 THz) was achieved at a maximum optical radiation power of 20 W in each band of the epitaxially stacked tunnel-junction semiconductor laser.

Arrays of strained nanoscale InP islands in an In0.49Ga0.51P host on a GaAs(100) substrate and InAs islands in a In0.53Ga0.47As host on an InP(100) substrate are obtained by metalorganic vapor-phase epitaxy (MOVPE). Their structural and photoluminescence properties are investigated. It is shown that the nanoscale islands that are formed measure 80 nm (InP/InGaP) and 25–60 nm (InAs/InGaAs). The photoluminescence spectra of the nanoscale islands display bands in the wavelength ranges 0.66–0.72 and 1.66–1.91 µm at 77 K with maxima whose position does not vary as the effective thickness of InP and InAs increases. The radiation efficiency of the nanoscale InP islands is two orders of magnitude greater than the luminescence intensity of the InAs islands.

A microscopic quantum-mechanical analysis of the intervalence band absorption of radiation (IVA) with hole transition into the spin-orbit split-off band has been made. It was found that IVA can heavily influence the threshold characteristics and quantum efficiency of heterolasers based on InAs. A detailed study of the threshold characteristics as functions of temperature and heterostructure parameters has been analyzed taking into account IVA.

Detailed data on temporal profiles, energy spectra, and spectral variability of hard X-ray and gamma-ray flares of solar origin have been obtained in the energy range from 10 keV to 10 MeV in the Helicon experiment for the entire period of observations, beginning with the solar activity maximum in 2001. Synchronously with the KONUS–WIND experiment onboard the U.S. Wind spacecraft, the Helicon experiment has also investigated cosmic gamma-ray bursts and soft gamma repeaters. The Helicon instrument performed unique observations of the giant flare from SGR1806-20 soft gamma repeater and of its reflection from the Moon. The intensity, history, and energy of the initial pulse of the giant flare from the gamma repeater are reconstructed for the first time with high reliability. A natural location of the Moon by a high-intensity flux of X-ray and gamma radiation has been recorded for the first time in the history of the extraterrestrial astronomy.

Control of spectral and spatial parameters of semiconductor lasers is a key element of their development and application. Surface integrated high-order distributed Bragg reflector (DBR) is the way to narrow diode laser spectrum preserving the conventional postgrowth process of laser diodes. On the other hand, high-order DBR has specific optical losses, which reduce optical output power. In this work we analyzed these specific optical losses and present design of laser resonator containing short front DBR, that allow to significantly reduce losses. With this approach, slope efficiency was greatly increased in contrast with conventional rear DBR laser diodes and 4 W optical output power with spectral width of less than 3 A was attained.

The original theory of postmortem rigidity has been developed and substantiated based on the concept of postmortem muscular contracture. It is postulated that the unrestricted growth of Ca2+ concentration in myoplasm of contractile cells during the immediate postmortal period brings the actin-myosine complex to the force generation state without subsequent relaxation.

Separately bounded InGaAsP/InP laser heterostructures with two stressed quantum wells emitting at a wavelength of 1.8 μm were obtained by metalorganic vapor-phase epitaxy. The laser diodes with a strip width of 100 μm provide for an output radiation power of 1.2 W in the continuous operation mode at a temperature of 20°C. A minimum threshold current density was 320 A/cm2 and a differential quantum efficiency was ηd=28% for a Fabry-Perot resonator length of 1.4 mm. The internal optical losses in the laser heterostructure studied amounted to 5.6 cm−1.

It is shown based on the historical and legal analysis that the designation of the child's status as a newborn infant throughout the period of its neonatal life till violent death "at or immediately after births" is the exclusive prerogative of the law-enforcement authorities. An original approach has been developed and recommended for the introduction into the expert practice. According to this proposal facts and arguments in the "Expert conclusions" should be formulated so as to avoid mentioning the child as newborn and to indicate only the duration of its extrauterine life. Such an approach leaves it to the law-enforcement authorities to decide in each concrete case whether the child should be designated as a newborn infant or not.

The main theories of myocardial lesions associated with a blunt chest injury proposed starting from the XIXth century till the present time are considered based on the overview of the literature data. It is shown that the theory of selective mechanical activation of ATP-dependent K+ channels is most promising for further investigations into the mechanisms of myocardial dysfunction resulting from blunt chest injuries. The authors emphasize the absence of the universally accepted theory explaining the mechanism behind traumatic cardiac troubles and its fatal outcome despite numerous studies of cardiac lesions in patients with a blunt chest injury. It dictates the necessity of further research, both clinical and experimental, for a deeper insight into the problem.

Results of photoluminescence (PL) studies of self-organized nanoscale InP islands (quantum dots, QDs) in the In0.49Ga0.51P matrix, grown on a GaAs substrate by metalorganic vapor phase epitaxy (MOVPE), are presented. Dependences of the PL efficiency on temperature in the range 77–300 K and on excitation level at pumping power densities of 0.01–5 kW/cm2 have been obtained. The PL spectra are a superposition of emission peaks from QDs and the wetting layer. Their intensity ratio depends on the pumping power and temperature, and the emission wavelength varies in the range 0.65–0.73 µm. At 77 K and low excitation level, InP QDs exhibit high temperature stability of the emission wavelength and high quantum efficiency.

The results of gamma-ray burst observations made in the 10 keV - 8 MeV range with Konus-B instrument on Granat spacecraft are presented. 19 gamma-ray bursts and 60 solar flares have been measured altogether in 27 days at a sensitivity level of 5×10−8 - 5×10−7 erg/cm2. The fast spectral variability of bursts and the presence of features in their spectra in the form of absorption and emission lines are confirmed.

Based on analyses of 756 intraocular pressure (IOP) measurements in different terms of postmortal period, it was established that decrease in IOP occurred simultaneously with increase in prescription of death coming and had its own pattern, which could be described with mathematical formulas, resulting from fundamental conservation laws.

The authors give general analysis of the work of 51-th Territorial Bureau of RF Forensic-Medical Expert Examination for on-site corpse inspection and detailed analysis of the work of the Moscow operative investigation group during 2006. The corpse inspection quality and effectiveness depend on timely and complete realization of organizing preparatory measures ensuring optimal conditions for the inspection. Adoption of new and use of existing scientific and technical methods make it possible to increase the reliability of conclusions regarding prescription of death coming.

The authors propose a modern approach to determination of intraocular pressure in corpses. The method holds promise for estimation of prescription of death coming.

Power and spectral characteristics of Fabry-Perot semiconductor lasers based on at high excitation levels in pulsed lasing mode (200 A, 100 ns, 10 kHz) are investigated and double-band lasing is reached.

Investigations of stimulated recombination processes and reasons of output optical power saturation at superhigh pump levels (up to 0.1 MA/cm 2 ) of semiconductor lasers based on wide variety of quantum well heterostructures (l=980- 1900 nm) are presented for the first time.

16 W CW room temperature front facet output optical power and 72% wall plug efficiency were attained in 100-/spl mu/m-aperture laser diodes based on quantum well heterostructure with ultra wide asymmetric waveguide.

The status of women physicists at the Ioffe Institute of the Russian Academy of Sciences is analyzed. In the Ioffe Physico‐Technical Institute (PTI), just 20% of the researchers are female. They work in all of the departments: in theoretical groups, 13%; in technological laboratories. up to 30%. Women account for 18% among PhDs and about 11% among Doctors of Science. From 1991 to 2001 there was a trend of growth in the fraction of young women at PTI (from 7% up to 20%). For the last 3 years the percentage of women among postgraduate students has held at 20%. There seems to be the following social phenomenon in the sciences in Russia: against a background of the aging of scientists as a whole, the younger the scientists are, the more likely they are to be women. Women scientists of Ioffe Institute take a hand in organizing the conferences, the physics schools, and the Physics of the Solid State and Semiconductors journals. It is very important to note that careful and reliable results of pseudo‐routine work of the PTI women are not always published. This fact exposes them to the “publications gap.” In spite of their high research levels, the PTI women physicists give talks at conferences and seminars much more seldom than their male colleagues. In the institute and the departments the male staff of the Academic Councils make decisions without taking gender issues into consideration. In addition, women account for only 3% of the laboratory heads. Now Russian young people are free from archaic gender stereotypes. We can say with certainty that the cultural and professional potential of women scientists is a considerable potential for the 21st century.

A set of high power single mode InGaAsP/InP ridge waveguide laser diodes emitting in 1440 - 1500 nm range on peak wavelengths used for optical fiber pumping were developed and fabricated. Room temperature continuous wave output power of 300 mW was reached. Stable operation on fundamental optical mode with only 1° increase of lateral far-field pattern FWHM was confirmed up to 180 mW output power.

Auger coefficients have been measured in five light emitting diodes (LEDs) with strained quantum wells inactive region covered a wide range of wavelength. LED were fabricated from identical high efficient laserheterostructures. The obtained Auger coefficients increase from 3x 1030 to 1.8x 1028 cm6/c as wavelengthchanges from 0.78 to 1.8 tim.Keywords: Auger recombination, strained quantum well, heterostructures, spontaneous emission INTRODUCTION The nonradiative processes of Auger recombination are relevant at high carrier density in 111—V semiconductorswith bandgap Eg < 1.2 eV. In heterolasers the electron and hole densities in the active region are high andAuger processes are potentially important. The influence of Auger recombination on the threshold current inheterolasers with bulk active region based on InGaAsP was shown experimentally [1—3] and theoretically [4—7].The difficulty with theories of Auger recombination is that information of the band parameters and the band

A comprehensive analytical model for the operating characteristics of semiconductor lasers with a low-dimensional active region is developed. Particular emphasis is given to the effect of capture delay of both electrons and holes from a bulk optical confinement region into a quantum-confined active region and an extended set of rate equations is used. We derive a closed-form expression for the internal quantum efficiency as an explicit function of the injection current and parameters of a laser structure. Due to either electron or hole capture delay, the internal efficiency decreases with increasing injection current above the lasing threshold thus causing sublinearity of the light-current characteristic of a laser.

A total of 176 sera from 73 patients with verified Lyme borreliosis at different stages of the disease are examined. Serological diagnosis was carried out by 2 methods: indirect immunofluorescence (IIF) with corpuscular B. burgdorferi antigen and enzyme immunoassay (EIA) with purified flagellar B. burgdorferi antigen (Dako). EIA with Dako antigen is more sensitive for the diagnosis of Lyme borreliosis at any period of the disease than IIF. Analysis of correlations between the results of IIF and EIA showed correlation in the levels of IgG but not IgM antibodies. The findings confirmed a previous hypothesis that inadequate antibacterial therapy before investigation decreases the level of antibodies to Borrelia. In patients with a history of Lyme borreliosis, antibodies to B. burgdorferi are detected less frequently by both IIF and EIA. Patients with persistent levels of antibodies to B. burgdorferi, even without clinical signs of infection, are in need of regular check-ups, because the prognostic significance of antibodies to B. burgdorferi is unknown and relapses may occur after months and years.

The Konus-Wind gamma-ray burst instrument on board the GGS-Wind spacecraft has operated flawlessly since launch in November 1994. The orbit of Wind, well beyond the magnetosphere and with no Earth occultation, provides a stable background for the continuous monitoring of gamma-ray bursts, as well as for X-ray transients such as the recent Bursting Pulsar. The two detectors viewing the ecliptic hemispheres have moderate energy resolution in the range from 10 keV to 10 MeV and time resolution down to 2 ms, permitting their use in the interplanetary network, such as for the event of 970228. A comprehensive data base has been obtained in which more than 750 gamma-ray bursts have been observed in the last three years. A brief review of the observations and a summary of the results are presented.

Circulating antituberculous antibodies in the sera from 89 patients with pulmonary tuberculosis and 11 patients with tumors and nonspecific inflammation in the lungs were evaluated using indirect hemagglutination and enzyme immunoassay. Specific antibodies were detected in 81.6 and 30% of tuberculous and nontuberculous patients, respectively.

Preliminary results with typical cosmic gamma‐ray burst observations from the Konus experiment on the GGS‐Wind spacecraft are presented.

The frequency of diagnostic titers of antibodies to Borrelia burgdorferi in 289 examinees suffering from neurological diseases made up 10.4%, while in the population this figure was under 1.9%. Lyme-borreliosis was detected in 11 (3.8%) patients, 2 of them had mixed infection with tick-borne viral encephalitis. In 10 patients (3.5%) the diagnosis of neuroborreliosis required verification with other techniques. It is thought valid to perform serological screening for neuroborreliosis only in patients with tick-born encephalitis to identify mixed infection.

The Konus-W experiment to be flown on board the GGS-Wind spacecraft is designed to observe gamma-ray bursts and solar flares with moderate spectral and high time resolution. Two large scintillators are used to provide omnidirectional sensitivity. The primary scientific objectives are the study of the continuum energy spectra and spectral features of these events in the energy range of 10 keV to 10 MeV, as well as their time histories in soft, medium, and hard energy bands, with a time resolution to 2 ms.

The examination of 231 rheumatic patients, 159 patients with reactive arthritis and 117 rheumatoid arthritis patients identified diagnostic titers of polyvalent antibodies to Borrelia in 6.6% of all the examinees with rheumatism, 11.9% with reactive arthritis and in 7.7% with RA. Lyme arthritis was diagnosed in 1.3% of reactive arthritis patients. To diagnose Lyme arthritis accurately, it is recommended to rest upon clinical symptoms which must be associated with high titers of IgG antibodies to Borrelia growing still higher in the follow-up period.

The data on UV, 1H NMR and mass spectroscopy confirmed that heliomycin produced by S. heliomycini and antibiotic 11-98 produced by S. olivocinereus were identical with resistomycin. The major minor component produced by S. heliomycini was shown to be resistoflavin which was also confirmed by physicochemical methods.

The primary task of the KONUS-W experiment to be flown on board the WIND spacecraft is to observe gamma-ray bursts and solar flares with moderate and high time resolution. The scientific objectives of the experiment include the study of continuum energy spectra and spectral features of these events in the energy range of 10 keV to 10 MeV as well as their time histories in soft, medium, and hard energy bands with a time resolution up to 2 ms. The general design and operation of the KONUS-W gamma-ray detector are briefly described, and the nomial program of burst observations is examined.

An investigation was made of the possibility of using reduced-pressure MOC hydride epitaxy to fabricate highly strained (compressive stress) InxGa1−xAs/In0.53Ga0.47As quantum wells on indium phosphide (100) substrates. The photoluminescence properties of these heterostructures were investigated. It was shown that these heterostructures are potentially useful for laser diodes emitting in the 1.5–2 μm range, which is important for environmental monitoring.