Superconductivity in highly disordered NbN nanowires.

The topic of superconductivity in strongly disordered materials has attracted significant attention. These materials appear to be rather promising for fabrication of various nanoscale devices such as bolometers and transition edge sensors of electromagnetic radiation. The vividly debated subject of intrinsic spatial inhomogeneity responsible for the non-Bardeen-Cooper-Schrieffer relation between the superconducting gap and the pairing potential is crucial both for understanding the fundamental issues of superconductivity in highly disordered superconductors, and for the operation of corresponding nanoelectronic devices. Here we report an experimental study of the electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. The temperature dependence of the critical current follows the textbook Ginzburg-Landau prediction for the quasi-one-dimensional superconducting channel I c âˆ¼ (1-T/T c)3/2. We find that conventional models based on the the phase slip mechanism provide reasonable fits for the shape of R(T) transitions. Better agreement with R(T) data can be achieved assuming the existence of short 'weak links' with slightly reduced local critical temperature T c. Hence, one may conclude that an 'exotic' intrinsic electronic inhomogeneity either does not exist in our structures, or, if it does exist, it does not affect their resistive state properties, or does not provide any specific impact distinguishable from conventional weak links.

[Delayed Copying of Unfamiliar Contour Shapes: Does Reaction Time Decrease with Growing Delay Reflect a Change in Internal Representation Of Fothcoming Movement?].

Group of 24 adults has performed the delayed reproduction (copying) of unfamiliar contour shapes (trajectory templates). Templates were shown for 250 ms and the participants were asked to reproduce them upon detecting acoustical go signal (short click). Go signal was delayed relatively to the end of a visual template exposure by T = 0, 500, 1000, 2000 or 4000 ms. Block design of the experiment was used when delay T was held constant within a block consisted of 32 trials. We analyzed reaction time (RT), mean movement time (MT) along a single segment of trajectory, and the mean dwell time (DT) in the vertices of the template. It is shown that RT does not depend monotonically on the delay T showing a decrease at T ≤ 1000 ms and increase at T ≤ 2000 ms. The RT of T curve is well described by a simple additive model that includes a linearly growing and an exponentially decaying terms. The linear growth reflects the foreperiod effect, i.e., decreasing capacity to predict an exact moment of go signal with the growing delay T [Niemi, Naatanen, 1981; Meulenbroek, Van Galen, 1988]. We suggested that exponentially decaying term may be caused by the internal representation of a trajectory undergoing some transformation during retention in the working memory.

[From Leonardo Da Vinci to present days; from the history of antiplague costume].

As a prototype of the antiplague costume can be considered a special clothing, which physicians in medieval Europe wear for protection in plague nidus. Inventor of the first antiplague costume is considered to be a French doctor Charles de Lorme (1619). Much later, in 1878, a Russian professor Pashutin V V offered to use a costume, which looked like a hermetically sealed "bag" with a special breathing device aimed at protection of medical staff. Later, professor O.I. Dogel's respirator became well-known (1889). At the beginning of 20th century as part of the antiplague costume was used a charcoal filter mask, invented by Zelinsky N.D. Requirements to order the use of modern means of individual protection when working in nidus of especially dangerous infections identified sanitary-epidemiological rules, which reflect issues of laboratory workers working and protective clothing, respiratory protection, and view, especially operation, the procedure of putting on, removing and disinfecting antiplague costumes, pneumocostumes, pneumohelmets, isolation suits, gas-protection boxes, etc.

Potential of a superconducting photon counter for heterodyne detection at the telecommunication wavelength.

Here, we report on the successful operation of a NbN thin film superconducting nanowire single-photon detector (SNSPD) in a coherent mode (as a mixer) at the telecommunication wavelength of 1550 nm. Providing the local oscillator power of the order of a few picowatts, we were practically able to reach the quantum noise limited sensitivity. The intermediate frequency gain bandwidth (also referred to as response or conversion bandwidth) was limited by the spectral band of a single-photon response pulse of the detector, which is proportional to the detector size. We observed a gain bandwidth of 65 MHz and 140 MHz for 7 × 7 µm2 and 3 × 3 µm2 devices, respectively. A tiny amount of the required local oscillator power and wide gain and noise bandwidths, along with unnecessary low noise amplification, make this technology prominent for various applications, with the possibility for future development of a photon counting heterodyne-born large-scale array.

[Delayed Copying of Unfamiliar Contour Shapes: Analysis of Potentials Related to Stimuli].

The high-density EEG was recorded and ERPs related to showing unfamiliar contour shapes and delivering imperative signal (a short sound) were estimated in the task requiring delayed motor reproduction of these shapes. A total of 22 right-handed adults participated in the experiment. They performed 5-blocks of trials corresponding-to 5 different delays (T= 0; 500, 1000, 2000 4000 ms) between the imperative signal relative to the end of the contour trajectory presentation. An ERP analysis showed that, unlike ERPs related to the contour shape presentation, those related to the imperative signal delivery do change with growing delay T. A subsequent analysis of cortical sources of the ERPs related to the imperative stimulus showed corresponding pronounced grows of reactivity of orbito-frontal cortex of the right hemisphere and a symmetrical bilateral grows of reactivity of dorsal parts of the sensorimotor cortex. The reported findings are discussed in the framework of the proposal according to which the internal representation of a trajectory undergoes a transi- tion from a sensory-specific format towards more abstract neither sensory- nor motor-specific format.

[A delayed motor production of open chains of linear strokes presented visually in static and dynamic modes: a comparison between 9 to 11 years old children and adults].

The production of drawing movements was studied in 29 right-handed children of 9-to-11 years old. The movements were the sequences of horizontal and vertical linear stokes conjoined at right angle (open polygonal chains) referred to throughout the paper as trajectories. The length of a trajectory varied from 4 to 6. The trajectories were presented visually to a subject in static (linedrawing) and dynamic (moving cursor that leaves no trace) modes. The subjects were asked to draw (copy) a trajectory in response to delayed go-signal (short click) as fast as possible without lifting the pen. The production latency time, the average movement duration along a trajectory segment, and overall number of errors committed by a subject during trajectory production were analyzed. A comparison of children's data with similar data in adults (16 subjects) shows the following. First, a substantial reduction in error rate is observed in the age range between 9 and 11 years old for both static and dynamic modes of trajectory presentation, with children of 11 still committing more error than adults. Second, the averaged movement duration shortens with age while the latency time tends to increase. Third, unlike the adults, the children of 9-11 do not show any difference in latency time between static and dynamic modes of visual presentation of trajectories. The difference in trajectory production between adult and children is attributed to the predominant involvement of on-line programming in children and pre-programming in adults.

[Significance of the individual helio-climatic factors in hemorrhagic fever with renal syndrome morbidity formation of population in the district of military units dislocation].

Been outlined the experience of mathematics modelling of natural phenomena for determination of the impact of individual factors and their combination on the epidemic process development. Found that 97,9% of the variation of haemorrhagic fever with renal syndrome index of population in the study area determine six climatic factors: the Wolf number, rainfall in November, the highest level of the river during floods, the temperature of air in October, the maximum and minimum levels of snow cover in February. As the most significant factors, contributing to the spread of the disease under study, been determine the parameters of air temperature and the height of snow. In the troops proposed to use approved methodology of mathematics modelling to predict changes of epidemiological situation for the disease and for timely organization of preventive measures to avoid introduction of infection in military units.

Absorption engineering of NbN nanowires deposited on silicon nitride nanophotonic circuits.

We investigate the absorption properties of U-shaped niobium nitride (NbN) nanowires atop nanophotonic circuits. Nanowires as narrow as 20nm are realized in direct contact with Si3N4 waveguides and their absorption properties are extracted through balanced measurements. We perform a full characterization of the absorption coefficient in dependence of length, width and separation of the fabricated nanowires, as well as for waveguides with different cross-section and etch depth. Our results show excellent agreement with finite-element analysis simulations for all considered parameters. The experimental data thus allows for optimizing absorption properties of emerging single-photon detectors co-integrated with telecom wavelength optical circuits.

[Internal representation of movement sequences built upon either static line drawings or trajectories of moving object].

In this paper, we explore the issue of the nature (perceptual, abstract, or motor) of neural codes used by CNS in order to store the internal representation of elements of a sequence of movements. Reported are the results of two experiments in which two independent groups of 16 right handed adults repeated, after a given delay, the piecewise trajectories (open polygonal chains) using the graphical tablet. A trajectory was shown either as a static line-drawing (static mode) or a small moving pointer (dynamic mode). The results show that: 1) for the delay varying from 0 to 1 s, the latent time of the trajectory production is greater in the dynamic than in the static mode, with the latent time is no different under to presentation conditions when the production delay reaches 3 s; 2) the latent time is exponentially decaying as the trajectory production delay increases from 0 to 3000 ms, with the characteristic decay time being different in the static (377 ms) and the dynamic (656 ms) presentation modes. The results of the present study are in line with the view that the internal representation of the sequence of movements is perceptual and it is converted into the motor codes at the later stages prior to movement execution. It is suggested in the paper that the observed exponential decay of the latent time might be related to the transformation of the early sensory (iconic) representation into the perceptual trajectory representation.

[Development and validation of the real-time PCR assay for the identification of viral agents causing acute respiratory infections in humans].

The real time PCR assay targeting influenza A and B virus, 5 subtypes of influenza A virus (seasonal H1N1, pandemic H1N1 (2009), seasonal H3N2, pathogenic for human subtypes of avian influenza H5 and H7), respiratory syncytial virus, and adenovirus was developed. The analytical sensitivity of the developed assay was 1 x 10(3) genome equivalents per ml. The diagnostic sensitivity of the method was 1 x l0(3)-10(4) viral particles per ml. Experiments with human DNA/cDNA and viral cDNA showed a markedly high diagnostic specificity of the developed PCR assay. In the assay of the developed PCR test, 50 nasopharyngeal swab specimens were tested. The etiology was identified in 33 samples.

[Epidemiologic characteristic of military unit location territories in Orenburg region].

The authors showed the real zoogenous infection hazard during the military units located in natural focus in Orenburg region. Among the zoonosis special place occupies the hemorrhagic fever with nephritic syndrome. The authors came to conclusion that months of seasonal pickup in Orenburg region are September - December, January of next year; in Totskiy region--November - February. Nowadays the territory of Totskiy region is a high risk area, Orenburg region--moderate risk zone, Yasnenskiy region--area without hemorrhagic fever with nephritic syndrome hazard.

[Experience in reducing the levels of raticides during open area disinfestations].

The experience in combining disinfestation and forestry engineering measures is described to achieve a long-term effect: in minimizing the number of murine rodents, which has considerably reduced the amount of poisoned baits placed into the environment when disinfestation is made in open areas.

[Endoprosthetic hip replacement in elderly patients with femoral neck fractures].

96 primary endoprosthetic hip replacements were performed in elderly patients with femoral neck fractures. The average age of the patients was 82,7 years. In cases of senile osteoporosis cement <> prosthesis was applied, when there were no signs of osteoporosis defined, non-cement <> construction was used. 53 (55,2%) patients were postoperatively followed-up during 1 to 7 years. Excellent result was achieved in 17 (32,1%) patients (>90 points on Harrison's scale), good result was registered in 21 (39,6%) patients (80-89 points), considered to be satisfactory (70-79 points) - in 15 (28,3%) patients.

Genetic diversity and geographic distribution of hantaviruses in Russia.

Haemorrhagic fever with renal syndrome (HFRS) is the most prevalent zoonotic disease in Russia. It is caused by several hantavirus species hosted by small rodents. We describe spatial and temporal patterns of HFRS incidence in the Russian Federation, and the geographic distribution of prevalent hantavirus species: Puumala (PUUV) and Dobrava (DOBV). Partial sequencing of nucleocapsid and glycoprotein genes of 117 PUUV strains and 78 DOBV strains revealed several distinct genetic subgroups. The RNA of Volga PUUV subgroup was detected in patients with HFRS and bank voles Myodes glareolus in the Volga Federal District, where the highest HFRS incidence rate has been registered yearly. The RNA of Siberian PUUV subgroup was found in M. glareolus in the trans-Ural Tyumen and Omsk Provinces, where human HFRS cases have been rare. During an HFRS outbreak in 2007 in the Central Federal District, when more than 1000 patients were affected, specific subgroups of DOBV were discovered in patients and rodents, mainly in the striped field mouse Apodemus agrarius. DOBV strains might have 8­9% of nucleotide difference although they were collected at places separated by 30­100 km. The RNA of a unique DOBV subgroup was discovered in the southern semi-desert Astrakhan Province, mainly in A. agrarius and tamarisk jird Meriones tamariscinus. No human HFRS cases were diagnosed in this province. Russian PUUV and DOBV strains have no close homologues among European strains. Our DOBV strains might be genetically grouped together with Central European DOBV strains isolated from A. agrarius, but not from Apodemus flavicollis. The Volga PUUV subgroup is to some extent similar to Baltic PUUV strain, and Finnish PUUV strains resemble the strains from the Siberian PUUV subgroup. Thus, PCRbased monitoring and typing provided the opportunity to delineate and expand the area of hantaviruses in Russia and to identify their new genetic variants.

[Use of native and lyophilized Loewenstein-Jensen's solid media in determining drug resistance on mycobacterium tuberculosis strains]. / Ispol'zovanie nativnoi i liofilizirovannoi sred Levenshteina-Iensena dlia opredeleniia lekarstvennoi ustoichivosti mycobacterium tuberculosis.

The results of determination of drug medium depend on both individual cultural properties of the strains tested and the type of the medium used. The composition of a medium is of significance for some strains: the latter grow in any medium and are characterized by the same spectrum of resistance. However, most drug-resistant strains have higher feeding demands which are not fully met on the lyophilized Löwenstein-Jensen medium. The strains in the lyophilized medium show an incomplete spectrum of resistance and less grow than do those in freshly prepared Löwenstein-Yersen medium.

[Biological properties of laboratory strains and clinical isolates of mycobacteria multiresistant to antitubercular preparations]. / Biologicheskie svoistva laboratornykh shtammov i klinicheskikh izoliatov mikobakterii, polirezistentnykh k protivotuberkuleznym preparatam.

Multiresistant M. tuberculosis strains show varying drug resistance, virulence and growth rates. The count of cells of some multiresistant strains in the guinea-pig parenchymatous organs after intracardiac inoculation was comparable with that of after inoculation with clinical isolates. Furthermore, some multiresistant strains were not inferior to sensitive clinical isolates. The findings lead to the conclusion that there is a wide range in the virulence of multiresistant strains and hence they can present an epidemiological hazard.

[Diagnosis, clinical picture and treatment policy in acute progressive forms of pulmonary tuberculosis under present-day epidemiological conditions]. / Diagnostika, klinika i taktika lecheniia ostroprogressiruiushchikh form tuberkuleza legkikh v sovremennykh épidemiologicheskikh usloviiakh.

Among 103 examinees, the most common clinical type was caseous pneumonia (45.6%), progressive fibrocavernous tuberculosis (20.4%), infiltrative caseous pneumonia (17.5%), disseminated tuberculosis (16.5%). Progression was characterized by cavern formation in 91.1% of patients, with large and giant caverns containing nonspecific microbes forming in 79.6%. All the patients were found to isolate bacteria and 93.5% showed their excess. Drug-resistant microbes were identified in 62.1% of patients; polydrug resistance was seen in 37.5%. Chemotherapy was performed at the first stage by using 5 drugs: isoniazid, rifampicin, pyrazinamide, ethambutol plus kanamycin or amikacin. A combination of reserve drugs, including prothionamide, ofloxacin (ciprofloxacin) amikacin, pyrazinamide, and ethambutol, was used in patients with polyresistance. Symptomatic and pathogenetic therapies should aim at correcting complications and concomitant abnormalities. Following 6 months, 80% of patients stopped isolating bacteria, the process became stable and they could be prepared for planned surgical treatment. In 20% of cases, the process was progressive and it required salvage operations.

[Characteristics of the radio-ecologic situation in the area of Totsk nuclear explosion and the immune status of schoolchildren residing in the vicinity]. / Kharakteristika radioékologicheskoi obstanovki v zone Totskogo iadernogo poligona i immunnyi status shkol'nikov, prozhivaiushchikh na blizhaishikh territoriiakh.

Environmental pollution caused by radioactive and non-radioactive chemicals, and the immunity of schoolchildren who reside in the area exposed to the Totsk nuclear explosion (1954) are comparatively analyzed. The results indicate that the area under study has higher levels of 137Cs than that of a control area. There were immunological changes in children, which are obviously associated with the nuclear explosion.