Mixotrophy of few strains of cyanobacteria and algae isolated from lampenflora communities

In the current study abilities for the mixotrophic growth of phototropic cave strains were observed. The influence of organic substrates on the growth rate on Chlorella vulgaris, Stichococcus bacillaris, Leptolyngbya foveolara, Scytonema were studied. In most cases glucose, maltose, glycerine, malate, acetate, sucrose, and peptone showed a stimulating effect on the culture growth rate by the dark and by the light incubation. Specific abilities for mixotrophic carbon consumption were proved

Eurasian-Scale Experimental Satellite-based Quantum Key Distribution with Detector Efficiency Mismatch Analysis

The Micius satellite is the pioneering initiative to demonstrate quantum teleportation, entanglement distribution, quantum key distribution (QKD), and quantum-secured communications experiments at the global scale. In this work, we report on the results of the 600-mm-aperture ground station design which has enabled the establishment of a quantum-secured link between the Zvenigorod and Nanshan ground stations using the Micius satellite. As a result of a quantum communications session, an overall sifted key of 2.5 Mbits and a total final key length of 310 kbits have been obtained. We present an extension of the security analysis of the realization of satellite-based QKD decoy-state protocol by taking into account the effect of the detection-efficiency mismatch for four detectors. We also simulate the QKD protocol for the satellite passage and by that validate our semi-empirical model for a realistic receiver, which is in good agreement with the experimental data. Our results pave the way to the considerations of realistic imperfection of the QKD systems, which are important in the context of their practical security.Comment: 8+2 pages, 5+2 figure

Influence of low-temperature plasma on green algae culture

Influence of low-temperature plasma, which was formed in a high-resource arc-discharge plasma jet in an argon-air mixture, was studied for a community of green algae as Chlorella vulgaris Beyerinck [Beijerinck] and Stichococcus bacillaris Nägeli. It was found that the plasma treatment for 10 minutes led to partial cell death. At the same time, the species of C. vulgaris were less sensitive to the plasma treatment than the species of S. bacillaris. After plasma exposure, the predominant growth of the latter culture was observed in comparison with the control samples. This effect can be explained by an activation of biochemical processes in the algae due to the interaction with radicals in the low-temperature plasma. The results obtained indicate the selectivity of the low-temperature plasma effect on green algae community

Magnetic Dirac semimetal state of (Mn,Ge)Bi2_2Te4_4

For quantum electronics, the possibility to finely tune the properties of magnetic topological insulators (TIs) is a key issue. We studied solid solutions between two isostructural Z$_2$ TIs, magnetic MnBi$_2$Te$_4$ and nonmagnetic GeBi$_2$Te$_4$, with Z$_2$ invariants of 1;000 and 1;001, respectively. For high-quality, large mixed crystals of Ge$_x$Mn$_{1-x}$Bi$_2$Te$_4$, we observed linear x-dependent magnetic properties, composition-independent pairwise exchange interactions along with an easy magnetization axis. The bulk band gap gradually decreases to zero for $x$ from 0 to 0.4, before reopening for $x>0.6$, evidencing topological phase transitions (TPTs) between topologically nontrivial phases and the semimetal state. The TPTs are driven purely by the variation of orbital contributions. By tracing the x-dependent $6p$ contribution to the states near the fundamental gap, the effective spin-orbit coupling variation is extracted. As $x$ varies, the maximum of this contribution switches from the valence to the conduction band, thereby driving two TPTs. The gapless state observed at $x=0.42$ closely resembles a Dirac semimetal above the Neel temperature and shows a magnetic gap below, which is clearly visible in raw photoemission data. The observed behavior of the Ge$_x$Mn$_{1-x}$Bi$_2$Te$_4$ system thereby demonstrates an ability to precisely control topological and magnetic properties of TIs

Value Orientation “Patriotism”: Essence, Content, and Assessment

Background. In the modern historical period, taking into account the current military-political situation, the actualization of the idea of patriotism as a comprehensive element of spiritual integrity of people is a condition for the preservation of Russia as an independent and unified state. The analysis of Russian and foreign scientific literature as well as of regulatory legal documents has shown the absence of a unified approach to the essence and content of the value orientation “patriotism”. There was also no tool for assessing the level of value orientation “patriotism” found. Objective. The article focuses on the development of a theoretical model of the value orientation “patriotism” and a methodology for assessing the level of its formation. Sample. 1600 citizens of the Russian Federation took part in the empirical study. Methods. The study was conducted with an expert survey, focus groups and a sociological survey. Results. The ANOVA by Kraskel — Wallis showed the validity of the developed methodology for assessing the value orientation of “patriotism” and the absence of statistically significant differences when using it on different sample populations. Conclusion. The article reveals the essence and content of the value orientation “patriotism”, develops and substantiates its theoretical model, which includes 8 components, as well as means of formation and levels of manifestation. In addition, the study developed and successfully tested a methodology for assessing the level of development of the value orientation “patriotism”

High-Quality Graphene Using Boudouard Reaction

Following the game-changing high-pressure CO (HiPco) process that established the first facile route toward large-scale production of single-walled carbon nanotubes, CO synthesis of cm-sized graphene crystals of ultra-high purity grown during tens of minutes is proposed. The Boudouard reaction serves for the first time to produce individual monolayer structures on the surface of a metal catalyst, thereby providing a chemical vapor deposition technique free from molecular and atomic hydrogen as well as vacuum conditions. This approach facilitates inhibition of the graphene nucleation from the CO/CO2 mixture and maintains a high growth rate of graphene seeds reaching large-scale monocrystals. Unique features of the Boudouard reaction coupled with CO-driven catalyst engineering ensure not only suppression of the second layer growth but also provide a simple and reliable technique for surface cleaning. Aside from being a novel carbon source, carbon monoxide ensures peculiar modification of catalyst and in general opens avenues for breakthrough graphene-catalyst composite production

High-Affinity Inhibitors of Human NAD+-Dependent 15-Hydroxyprostaglandin Dehydrogenase: Mechanisms of Inhibition and Structure-Activity Relationships

BACKGROUND: 15-Hydroxyprostaglandin dehydrogenase (15-PGDH, EC 1.1.1.141) is the key enzyme for the inactivation of prostaglandins, regulating processes such as inflammation or proliferation. The anabolic pathways of prostaglandins, especially with respect to regulation of the cyclooxygenase (COX) enzymes have been studied in detail; however, little is known about downstream events including functional interaction of prostaglandin-processing and -metabolizing enzymes. High-affinity probes for 15-PGDH will, therefore, represent important tools for further studies. PRINCIPAL FINDINGS: To identify novel high-affinity inhibitors of 15-PGDH we performed a quantitative high-throughput screen (qHTS) by testing >160 thousand compounds in a concentration-response format and identified compounds that act as noncompetitive inhibitors as well as a competitive inhibitor, with nanomolar affinity. Both types of inhibitors caused strong thermal stabilization of the enzyme, with cofactor dependencies correlating with their mechanism of action. We solved the structure of human 15-PGDH and explored the binding modes of the inhibitors to the enzyme in silico. We found binding modes that are consistent with the observed mechanisms of action. CONCLUSIONS: Low cross-reactivity in screens of over 320 targets, including three other human dehydrogenases/reductases, suggest selectivity of the present inhibitors for 15-PGDH. The high potencies and different mechanisms of action of these chemotypes make them a useful set of complementary chemical probes for functional studies of prostaglandin-signaling pathways. ENHANCED VERSION: This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S2