Multilayer corrosion-resistant material based on iron-carbon alloys

In this study, the architecture of a multilayer metallic material of iron-carbon alloys with an internal protector was developed based on theoretical studies. The operability of the proposed architecture was experimentally verified using gravimetry and electrochemical analysis. The internal position of the protector enabled the modification of the mechanism of corrosion. The stages of corrosion of the multilayer material were revealed; the material was observed as useable until the third layer was perforated. To demonstrate the obtained results, the authors conducted a set of experiments using X-ray microscopy and scanning electron microscopy with an electron probe analysis of the chemical composition. The cost of the developed material is within the same range as widely used corrosion-resistant stainless austenite steels; and in terms of corrosion resistance, this material is comparable to palladium, molybdenum, nickel, and Hastelloy.

Metagenomic data of the microbial community of lab-scale nitritation-anammox sequencing-batch bioreactor performing nitrogen removal from synthetic wastewater

The nitritation-anammox process, which involves partial aerobic oxidation of the ammonium to nitrite and following oxidation of ammonium by nitrite to molecular nitrogen, is an efficient and cost-effective approach for biological nitrogen removal from wastewater. To characterize the microbial communities involved in the nitrogen and carbon cycles in wastewater treatment bioreactors employing this process, we sequenced the metagenome of a sludge sample collected from the lab-scale nitritation-anammox sequencing-batch reactor. At the phylum level, Proteobacteria and Chloroflexi were the most numerous groups. Anammox bacteria belonged to the genus Candidatus Brocadia. The obtained data will help to investigate the taxonomical and functional diversity the microbial communities involved in nitritation-anammox process, and will be used for genome-based analysis of uncultured bacterial lineages. The raw sequencing data is available from the NCBI Sequence Read Archive (SRR9831403) database under the BioProject PRJN0A55627.

New Emerging One Dimensional Nanostructure Materials for Gas Sensing Application: A Mini Review

Background:

Nanomaterials have numerous potential applications in many areas such as electronics, optoelectronics, catalysis and composite materials. Particularly, one dimensional (1D) nanomaterials such as nanobelts, nanorods, and nanotubes can be used as either functional materials or building blocks for hierarchical nanostructures. 1D nanostructure plays a very important role in sensor technology.

Objective:

In the current review, our efforts are directed toward recent review on the use of 1D nanostructure materials which are used in the literature for developing high-performance gas sensors with fast response, quick recovery time and low detection limit. This mini review also focuses on the methods of synthesis of 1D nanostructural sensor array, sensing mechanisms and its application in sensing of different types of toxic gases which are fatal for human mankind. Particular emphasis is given to the relation between the nanostructure and sensor properties in an attempt to address structure-property correlations. Finally, some future research perspectives and new challenges that the field of 1D nanostructure sensors will have to address are also discussed.

Inhibition of telomerase activity by splice-switching oligonucleotides targeting the mRNA of the telomerase catalytic subunit affects proliferation of human CD4+ T lymphocytes

Telomerase activity is regulated at the mRNA level by alternative splicing (AS) of its catalytic subunit hTERT. The aim of this study was to define the ability of splice-switching oligonucleotides (SSOs) that pair with hTERT pre-mRNA to induce AS and inhibit telomerase activity in human CD4⁺ T lymphocytes. SSOs that blocked the binding of a single splicing regulatory protein, SRp20 or SRp40, to its site within intron 8 of hTERT pre-mRNA demonstrated rather moderate capacities to induce AS and inhibit telomerase. However, a SSO that blocked the interaction of both SRp20 and SRp40 proteins with pre-mRNA was the most active. Cultivation of lymphocytes with spliced hTERT and inhibited telomerase resulted in the reduction of proliferative activity without significant induction of cell death. These results should facilitate further investigation of telomerase activity regulation, and antitelomerase SSOs could become promising agents for antiproliferative cell therapy.

Endonuclease G modulates the alternative splicing of deoxyribonuclease 1 mRNA in human CD4+ T lymphocytes and prevents the progression of apoptosis

Apoptotic endonucleases act cooperatively to fragment DNA and ensure the irreversibility of apoptosis. However, very little is known regarding the potential regulatory links between endonucleases. Deoxyribonuclease 1 (DNase I) inactivation is caused by alternative splicing (AS) of DNase I pre-mRNA skipping exon 4, which occurs in response to EndoG overexpression in cells. The current study aimed to determine the role of EndoG in the regulation of DNase I mRNA AS and the modulation of its enzymatic activity. A strong correlation was identified between the EndoG expression levels and DNase I splice variants in human lymphocytes. EndoG overexpression in CD4⁺ T cells down-regulated the mRNA levels of the active full-length DNase I variant and up-regulated the levels of the non-active spliced variant, which acts in a dominant-negative fashion. DNase I AS was induced by the translocation of EndoG from mitochondria into nuclei during the development of apoptosis. The DNase I spliced variant was induced by recombinant EndoG or by incubation with EndoG-digested cellular RNA in an in vitro system with isolated cell nuclei. Using antisense DNA oligonucleotides, we identified a 72-base segment that spans the adjacent segments of exon 4 and intron 4 and appears to be responsible for the AS. DNase I-positive CD4⁺ T cells overexpressing EndoG demonstrated decreased progression towards bleomycin-induced apoptosis. Therefore, EndoG is an endonuclease with the unique ability to inactivate another endonuclease, DNase I, and to modulate the development of apoptosis.

Porous carbon-based adsorption systems for natural gas (methane) storage

The use of gas fuel has considerable environmental advantages over traditional types of fuel based on petroleum products or fossil coal. The adsorption technology for methane (natural gas) uptake, storage and transportation can serve as a connecting link in gas supply to customers. The review considers characteristics of adsorption systems for methane storage. The key methods used for the synthesis of microporous carbon adsorbents based on various organic and inorganic carbon-containing compounds are described. Methods for increasing the efficiency of methane storage systems based on carbon adsorbents are analyzed. Theoretical approaches to optimization of the properties of methane – carbon adsorbent systems are discussed.

The bibliography includes 174 references.

Measuring corrosion rate and protector effectiveness of advanced multilayer metallic materials by newly developed methods

The paper estimates corrosion resistance of new multilayer metallic materials with internal protector against pitting. Using an electron microscope method, the mechanism of the layers' corrosive destruction has been experimentally substantiated. The authors have suggested chemical and electrochemical methods of accelerated corrosion tests allowing for determining the corrosion destruction rate. The electrochemical method reveals the limiting stage of the process and allows calculating the mass corrosion index and substantiating the choice of protector for the specific corrosive medium. The chemical method allows for quantitative assessment of the internal protector's effectiveness and for defining the multilayer/monometallic material corrosion resistance ratio.

Murine regulatory T cells induce death of effector T, B, and NK lymphocytes through a contact-independent mechanism involving telomerase suppression and telomere-associated senescence

Regulatory T cells (Tregs) suppress the activity of effector T, B and NK lymphocytes and sustain immunological tolerance, but the proliferative activity of suppressed cells remains unexplored. In the present study, we report that mouse Tregs can induce replicative senescence and the death of responder mouse CD4⁺CD25^- T cells, CD8⁺ T cells, B cells and NK cells in vitro and in vivo. Contact-independent in vitro co-cultivation with Tregs up-regulated endonuclease G (EndoG) expression and its translocation to the nucleus in responder cells. EndoG localization in the nucleus induced alternative mRNA splicing of the telomerase catalytic subunit Tert and telomerase inhibition. The lack of telomerase activity in proliferating cells led to telomere loss followed by the development of senescence and cell death. Injection of Tregs into mice resulted in EndoG-associated alternative splicing of Tert, telomerase inhibition, telomere loss, senescence development and increased cell death in vivo. The present study describes a novel contact-independent mechanism by which Tregs specify effector cell fate and provides new insights into cellular crosstalk related to immune suppression.

Water treatment by new-generation graphene materials: hope for bright future

Water is the most important and essential component of earth's ecosystem playing a vital role in the proper functioning of flora and fauna. But, our water resources are contaminating continuously. The whole world may be in great water scarcity after few decades. Graphene, a single-atom thick carbon nanosheet, and graphene nanomaterials have bright future in water treatment technologies due to their extraordinary properties. Only few papers describe the use of these materials in water treatment by adsorption, filtration, and photodegradation methods. This article presents a critical evaluation of the contribution of graphene nanomaterials in water treatment. Attempts have been made to discuss the future perspectives of these materials in water treatment. Besides, the efforts are made to discuss the nanotoxicity and hazards of graphene-based materials. The suggestions are given to explore the full potential of these materials along with precautions of nanotoxicity and its hazards. It was concluded that the future of graphene-based materials is quite bright.

Alternative splicing of telomerase catalytic subunit hTERT generated by apoptotic endonuclease EndoG induces human CD4+ T cell death

Telomerase activity is regulated by alternative splicing of its catalytic subunit human Telomerase Reverse Transcriptase (hTERT) mRNA. Induction of a non-active spliced hTERT leads to inhibition of telomerase activity. However, very little is known about the mechanism of hTERT mRNA alternative splicing. The aim of this study was to determine the role of the apoptotic endonuclease EndoG in alternative splicing of hTERT and telomerase activity. A strong correlation was identified between EndoG expression levels and hTERT splice variants in human CD4⁺ and CD8⁺ T lymphocytes. Overexpression of EndoG in CD4⁺ T cells down-regulated the expression of the active full-length hTERT variant and up-regulated expression of the non-active spliced variant. A reduction in full-length hTERT transcripts down-regulated telomerase activity. Long-term in vitro cultivation of EndoG-overexpressing CD4⁺ T cells led to dramatically shortened telomeres, conversion of cells into a replicative senescence state, and activation of the BCL2/BAX-associated apoptotic pathway finally leading to cell death. These data indicated the participation of EndoG in alternative mRNA splicing of the telomerase catalytic subunit hTERT, regulation of telomerase activity and determination of cell fate.

[Candidatus "Jettenia moscovienalis" sp. nov., a New Species of Bacteria Carrying out Anaerobic Ammonium Oxidation]

A new species of bacteria oxidizing ammonium with nitrite under anoxic conditions was isolated from the activated sludge of a semi-industrial bioreactor treating digested sludge of the Kuryanovo wastewater treatment plant (Moscow, Russia). Physiological, morphological, and molecular genetic characterization of the isolate was carried out. The cells were ovoid (-0.5 x 0.8 μm), with the intracellular membrane structures characteristic of anammox bacteria (anammoxosome and paryphoplasm); unlike other anammox bacteria, it possessed extensive intracellular membrane structures located in layers parallel to the cytoplasmic membrane, but never close to the anammoxosome. The cells formed aggregates 5-28 μm in diameter and readily attached to solid surfaces. The cells were morphologically labile, easily plasmolyzed, and lost their content. Doubling time was 28 days, μ(max) = 0.025 day(-1); optimal temperature and pH for growth were 20-45 degrees C and 8.0, respectively. Phylogenetic analysis of the 16S rRNA gene sequences suggested its classification as a new species of the candidate genus Jettenia (order Planctomycetales). The name Candidatus "Jettenia moscovienalis" sp. nov. was proposed for the new bacterium.

[Microbial composition of the activated sludges of the Moscow wastewater treatment plants]

The contribution of the major technologically important microbial groups (ammonium- and nitrite-oxidizing, phosphate-accumulating, foam-inducing, and anammox bacteria, as well as planctomycetes and methanogenic archaea) was characterized for the aeration tanks of the Moscow wastewater treatment facilities. FISH investigation revealed that aerobic sludges were eubacterial communities; the metabolically active archaea contributed insignificantly. Stage II nitrifying microorganisms and planctomycetes were significant constituents of the bacterial component of activated sludge, with Nitrobacter spp. being the dominant nitrifier. No metabolically active anammox bacteria were revealed in the sludge from aeration tanks. The sludge from the aeration tanks using different wastewater treatment technologies were found to differ in characteristics. Abundance of the nitrifying and phosphate-accumulating bacteria in the sludges generally correlated with microbial activity, in microcosms and with efficiency of nitrogen and phosphorus removal from wastewater. The highest microbial numbers and activity were found in the sludges of the tanks operating according to the technologies developed in the universities of Hanover and Cape Town. The activated sludge from the Novokur yanovo facilities, where abundant growth of filamentous bacteria resulted in foam formation, exhibited the lowest activity The group of foaming bacteria included Gordonia spp. and Acinetobacter spp., utilizing petroleum and motor oils, Sphaerotilus spp. utilizing unsaturated fatty acids, and Candidatus 'Microthrix parvicella'. Thus, the data on abundance and composition of metabolically active microorganisms obtained by FISH may be used for the technological control of wastewater treatment.

[A novel bacterium carrying out anaerobic ammonium oxidation in a reactor for biological treatment of the filtrate of wastewater fermented residue]

A new genus and species of bacteria capable of ammonium oxidation under anaerobic conditions in the presence of nitrite is described. The enrichment culture was obtained from the Moscow River silt by sequential cultivation in reactors with selective conditions for anaerobic ammonium oxidation. Bacterial cells were coccoid, -0.4 x 0.7 mm, with the intracellular membrane structures typical of bacteria capable of anaerobic ammonium oxidation (anammoxosome and paryphoplasm). The cells formed aggregates 5-25 μm in diameter (10 μm on average). They were readily adhered to solid surfaces. The cells were morphologically labile, they easily lost their content and changed their morphology during fixation for electron microscopy. The organism was capable of ammonium oxidation with nitrite. The semisaturation constants Ks for nitrite and ammonium were 0.38 mg N-NO2/L and 0.41 mg N-NH4/L, respectively. The maximal nitrite concentrations for growth were 90 and 75 mg N-NO2/L for single and continuous application, respectively. The doubling time was 32 days, μ(max) = 0.022 day(-1), the optimal temperature and pH were 20 degrees C and 7.8-8.3, respectively. According to the 16S rRNA gene sequencing, the bacterium was assigned to a new genus and species within the phylum Planctomycetes. The proposed name for the new bacterium is Candidatus Anammoximicrobium moscowii gen. nov., sp. nov. (a microorganisms carrying out anaerobia ammonium oxidation, isolated in the Moscow region).

[Lipid composition of activated sludge in a pilot plant for anaerobic ammonium oxidation]

The lipid composition of the microbial community inhabiting activated sludge in a pilot reactor for the anaerobic oxidation of ammonium (anammox) at the Kur'yanovo Treatment Plant (Moscow) has been studied. The fatty acid composition is mostly based on common fatty acids C14-C18 (95%) with both normal and isomeric structures. The biomass of activated sludge was found to contain lipids with the so-called ladderane substances (ladder alcohols and fatty acids) that are common for anammox bacteria: C20-[3]-ladderane and C20-[5]-ladderane alcohols and C18-and C20-[3]-ladderane and C18- and C20-[5]-ladderane acids. In addition, the native extract contained both simple and compound ethers of the above-mentioned substances with residues of phosphocholine, phosphoethanolamine, and phosphoglycerine. The spectra of the electron impact and tandem mass spectrometry of certain substances have been obtained and published for the first time.

[Medical apparatuses based on gas lasers]

Medical laser apparatuses available from Plasma, Ltd., are reviewed. The effects of therapeutic physical factors provided by these apparatuses on the pathological processes in human body are concisely described. Technical characteristics of the apparatuses are specified.

[A portable impedance meter for monitoring liquid compartments of human body under space flight conditions]

A portable two-frequency tetrapolar impedance meter was developed to study the state of liquid compartments of human body under zero-gravity conditions. The portable impedance meter makes it possible to monitor the hydration state of human body under conditions of long-term space flight on board international space station.