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Surfactin is a powerful surfactant of biological origin with a wide range of potential applications in industry and medicine. The main factor limiting its active utilization is the high cost of production. Due to the complexity of the structure, the chemical synthesis of surfactin is unprofitable, so the main approach to its production is microbiological synthesis. This work demonstrated for the first time the ability of B. subtilis NCIB 3610 to synthesize surfactin. This strain possesses properties lost by most B. subtilis model laboratory strains. The nucleotide sequences of genomes of B. subtilis NCIB 3610 and B. subtilis PY79 strains have been obtained by nanopore sequencing. А comparative analysis of the obtained genomes with genome of B. subtilis 168, genetically modified derivatives of which are patented surfactin producers, has been performed. No mutations affecting surfactin biosynthesis were found in the NCIB 3610 strain, while in the PY79 strain mutations were identified in genes involved in cellular processes competing with biosynthesis of the surfactin. Thus, the results obtained in this work make it possible to consider B. subtilis NCIB 3610 and PY79 as alternative base strains for the genetic engineering design of surfactin superproducers.

We propose a new technique of remote wind measurements based on Doppler analysis of a CO2 absorption line in the 1.605 µm overtone band measured in the direct Sun observation geometry. Heterodyne spectroradiometric measurements of the solar radiation passing through the atmosphere provide an unprecedented spectral resolution up to λ/δλ∼6×107, with a signal-to-noise ratio of more than 100. The shape of the individual rotational line profile provides an unambiguous relationship between the offset from the line center and the altitude at which the respective part of the line profile is formed. Therefore, an inverse problem may be posed in order to retrieve the vertical distribution of wind because with retrievals the vertical resolution is compromised by a spectral resolution and the signal-to-noise ratio of the measurements. A close coincidence between the measured and synthetic absorption line is reached, with retrieved wind profiles between the surface and 50 km being in good agreement with reanalysis models. This method may pose an alternative to widely employed lidar and radar techniques.

The detection of minor species in the presence of large amounts of similar main components remains a key challenge in analytical chemistry, for instance, to obtain isotopic fingerprints. As an alternative to the classical NMR scheme based on coherent excitation and detection, here we introduce an approach based on spin-noise detection. Chemical shifts and transverse relaxation rates are determined using only the detection circuit. Thanks to a nonlinear effect in mixtures with small chemical shift dispersion, small signals on top of a larger one can be observed with increased sensitivity as bumps on a dip; the latter being the signature of the main magnetization. Experimental observations are underpinned by an analytical theory: the coupling between the magnetization and the coil provides an amplified detection capability of both small static magnetic field inhomogeneities and small NMR signals. This is illustrated by two-bond 12 C/ 13 C isotopic measurements. Nuclear spin noise allows passive monitoring of magnetization using the sole NMR detection circuit. Here, the authors report spectroscopic signatures of low abundance molecules and of weak magnetic field gradients which are nonlinearly amplified by cooled-coil probes and large overlapping signals.

Nature Communications 8: Article number: 13914 (2017); Published 9 January 2017; Updated 19 April 2017 This Article contains typographical errors in Equation 1, where the fraction line incorrectly extends across the entire equation. The correct form of Equation 1 is as follows:

In this paper, we studied the operability of various components of vacuum electronic devices manufactured using the novel chemical metallization of photopolymer 3D-printed structures technology (CMPS), which is being applied at the Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), for operation from microwave to sub-terahertz ranges. The key feature of this production method is the 3D printing (SLA/DLP, MJM technologies) of products and their further metallization. The paper presents the main stages of the process of chemical copper plating of polymer bases in various electrodynamic systems with complex shapes. A significant difference in the geometry and operating conditions of the created elements forms certain approaches to their production, as described in this work. Experimental studies of the implemented microwave components were carried out up to 700 GHz in the “cold” measurements; some electrodynamic structures were examined under conditions of sub-gigawatt peak power; and complex-shaped electrodes with cooling channels were tested under a continuous high thermal load. The conducted research has demonstrated the high potential of the developed methods of additive manufacturing of microwave device components and the prospects for their successful application in the described areas.

Nuclear spin noise spectroscopy in the absence of radio frequency pulses was studied under the influence of pulsed field gradients (PFGs) on pure and mixed liquids. Under conditions where the radiation-damping-induced line broadening is smaller than the gradient-dependent inhomogeneous broadening, echo responses can be observed in difference spectra between experiments employing pulsed field gradient pairs of the same and opposite signs. These observed spin noise gradient echoes (SNGEs) were analyzed through a simple model to describe the effects of transient phenomena. Experiments performed on high-resolution nuclear magnetic resonance (NMR) probes demonstrate how refocused spin noise behaves and how it can be exploited to determine sample properties. In bulk liquids and their mixtures, transverse relaxation times and translational diffusion constants can be determined from SNGE spectra recorded following tailored sequences of magnetic field gradient pulses.

— Within the framework of this work, using a three-dimensional numerical model of the general circulation of the Martian atmosphere MAOAM (Martian Atmosphere: Observation and Modeling), also known as MPI-MGCM (Max Planck Institute Martian General Circulation Model), we simulated the planet’s hydrological cycle during the 28 and 34 Martian years (MY28 and MY34) dust storm seasons. A quantitative assessment of the photodissociation of water vapor under the influence of solar radiation at the Lyman-alpha wavelength has been carried out. The simulation results are compared with individual profiles obtained with the Atmospheric Chemistry Suite (ACS) spectrometer installed on the ExoMars Trace Gas Orbiter (TGO) spacecraft. The MAOAM model has a spectral dynamical core and successfully predicts the temperature regime of Mars through the use of physical parameterizations that are characteristic of both Earth and Martian models. The hydrodynamic block of the model includes the transfer scheme, microphysics of water vapor and ice, heterogeneous nucleation, sedimentation, photodissociation, and exchange of water with the surface. Studies show the effect of dust storms on both the total water vapor content in the atmosphere and its vertical distribution. More intense pumping of water vapor into the upper atmosphere during dust storms provides more intense photodissociation of water vapor (in some seasons up to 6.5 tons per second in total in the entire atmosphere). The strongest photodissociation is observed at heights of 50 to 80 km for MY34 and 70 to 80 km for MY28. The dissociated water vapor can then potentially become a source of hydrogen dissipation into space, followed by a decrease in the mass of water on the planet.

This book describes nuclear magnetic resonance NMR methods which are used to study translational dynamics of molecules in different complex systems including systems made of synthetic and natural polymers, tissues and the porous heterogeneous systems of

This short paper corresponds to the talk given as an invited speaker during the ITaMSA 2021 conference, Bogor (Indonesia). In this short paper, the reader can find the major concepts used for the modeling and simulation of agroecosystems. On the one hand, the concept of Multi-Agents Systems is presented with the main properties of these systems. On the second hand, the foundations and the characteristics of Cellular Automata are detailed. Designing a system with a set of agents allows the modeler to focus on the interactions between entities. This type of modeling is more natural than a classical mathematical approach at the population’s scale. Finally, a case study is presented. This case study is designed with a freely available tool developed at the University of Brest (France) based on a multi-agents engine with Cellular Automata facilities.

There are several points arbitrarily located in space. The problem is - to determine the coordinates of a new point, the sum of all distances to all points from which is to be minimal. Initially Pierre de Fermat, Evangelista Torricelli, and Jacobi Steiner had solved this problem but only for three points on the plane and the distance function of Euclid. For more than four on the plane the exact analytical solution have not been found yet. In this paper the algorithms for numerical determination of coordinates of Fermat-Steiner point both on the plane and in three-dimensional space for arbitrary distance metric have been presented, along with the visualization of testing.