Analysis of phytotoxicity and plant growth stimulation by multi-walled carbon nanotubes

Nanotechnology is a rapidly expanding area of science and technology, which has gained a great interest due extraordinary properties of nanomaterials with numerous potential fields for practical application. Meanwhile, carbon nanotubes (CNTs) are among the ten most-produced engineered nanomaterials worldwide with applications in automotive industry, building and construction, electronics, and many other industrial sectors, showing also a great potential for integration into environmental and agricultural applications. However, during the last decade it has been demonstrated that nanomaterials can exert significant and extremely variable effects also on living organisms. In higher plants, both, positive and negative responses on growth and development have been reported but the related mechanisms are still not entirely understood. This study presents a systematic assessment of CNT effects on representative crops under standardized conditions with special emphasis on interactions with plant nutrition. After the introductory background (Chapter 1), presenting a comprehensive literature review on carbon nanomaterials with special emphasis on plant responses, environmental and agricultural applications, Chapter 2 describes the impact of selected multi-walled carbon nanotubes (MWCNTs) on seed germination and early seedling development of different crops (soybean−Glycine max, maize−Zea mays, and common bean−Phaseolus vulgaris). In face of highly variable plant responses to CNT treatments reported in the literature, the study was designed as a systematic analysis under standardized growth conditions, dissecting the effects of one single type of MWCNTs, depending on plant species, MWCNT dosage, duration of exposure to MWCNT treatments, and plant-developmental stage, including imbibition, germination and seedling development. Short-term seed treatments (36 h) with MWCNTs reduced the speed of water uptake particularly by soybean seeds, associated with an increased germination percentage and reduced formation of abnormal seedlings. However, during later seedling development, negative effects on fine root production were recorded for all investigated plant species. Inhibition of root growth was associated with reduced metabolic activity of the root tissue and a reduction of nitrate uptake, which could be mainly attributed to the smaller root system. The results demonstrated that even under standardized growth conditions largely excluding external factors, plant responses to MWCNT exposure exhibit differences, depending on plant species but also on the physiological status and the developmental stage of individual plants. Soybean was selected as a model plant for further studies since both, positive and negative effects of the same dose of MWCNTs (1000 mg L-1) could be observed even in the same individual plants. Chapter 3 investigates effects of short-term soybean seed exposure (36 h) to MWCNTs on seedling development, depending on the nutrient availability of the substrate. At 8 DAS stunted growth and poor fine root production were first detectable in seedlings germinating on moist filter paper without additional nutrient supply. This effect was preceded by reduced metabolic activity of the seedling tissues detectable by vital staining already at 2 DAS. Root growth inhibition was a long-lasting effect, detectable in soil culture up to 38 DAS. More detailed investigations revealed zinc (Zn) deficiency as a major growth-limiting factor. The growth of affected soil-grown plants was recovered by foliar application of ZnSO4 or by cultivation in nutrient solution supplied with soluble ZnSO4. A more detailed investigation of the physiological mechanisms related with the inhibitory effects of MWCNTs on plant growth is presented in Chapter 4. Oxidative stress was identified as a major factor determining MWCNT-induced root growth inhibition in soybean, demonstrated by recovery of root development after external supplementation with antioxidants. Induction of oxidative stress by MWCNT application was detectable already after the 36 h imbibition period particularly in the tips of the radicle as indicated by accumulation of superoxide anions, reduced triphenyltetrazolium chloride vital staining, and induction of superoxide dismutase activity. The expression pattern of the oxidative stress indicators coincided with preferential accumulation of MWCNTs in the cells of the root tip and was reverted by external application of proline as antioxidant. MWCNT-induced plant damage could be reverted by external supplementation of micronutrients (Zn, Cu, Mn) as important cofactors for various enzymes involved in oxidative stress defense (SOD, biosynthesis of antioxidative phenolics). Accordingly, SOD activity increased in seedling roots after Zn supplementation. During germination, the CNT treatments inhibited particularly the Zn translocation from the cotyledons to the growing seedling, and CNTs exhibited a selective adsorption potential for Zn and Cu, which may be involved in internal immobilization of micronutrients. Therefore, this study demonstrated for the first time that phytotoxicity of CNTs is linked with disturbances of micronutrient homeostasis during seedling development. Implications for environmental phytotoxicity assessment of MWCNTs and their potential applications in agriculture are discussed in a final overview presented in Chapter 5.Nanotechnologien repräsentieren ein extrem schnell expandierendes, wissenschaftliches und technologisches Arbeitsfeld, das aufgrund herausragender Eigenschaften und zahlreicher potenzieller, praktischer Anwendungsmöglichkeiten von Nanomaterialien derzeit große Aufmerksamkeit erfährt. Sogenannte Carbon Nanotubes (CNTs) gehören mittlerweile weltweit zu den zehn meistproduzierten Nanomaterialen mit Anwendungen für Verkehrs,- und Transporttechnologien, im Bau-, und Ingenieurswesen, in der Elektrotechnik und vielen anderen Anwendungsbereichen, mit vielversprechenden Möglichkeiten auch in der Umwelttechnik und der Landwirtschaft. Während der vergangen zehn Jahre wurde allerdings deutlich, dass Nanomaterialien signifikante und oft extrem variable Wirkungen auch auf lebende Organismen haben können. Bei höheren Pflanzen wurden sowohl positive als auch negative Effekte auf das Wachstum und die pflanzliche Entwicklung berichtet, und die zugrundeliegenden Mechanismen sind nach wie vor unklar. In der vorliegenden Untersuchung wird eine systematische Bewertung von CNT Wirkungen auf repräsentative Kulturpflanzenarten unter standardisierten Bedingungen vorgestellt, mit besonderem Augenmerk auf mögliche Wechselwirkungen mit der pflanzlichen Ernährung. Nach einem einleitenden Überblick (Kapitel 1), der eine umfassenden Literaturstudie zu Carbon-Nanomaterialien mit Schwerpunkt auf pflanzlichen Wechselwirkungen und Anwendungsperspektiven in der Umwelttechnologie und in der Landwirtschaft vorstellt, beschreibt Kapitel 2 die Wirkungen ausgewählter, so genannter Multiwalled Carbon Nanotubes (MWCNTs) auf die Keimung, und die Keimlingsentwicklung verschiedener Kulturpflanzenarten (Soja Glycine max, Mais Zea mays, und Phaseolus-Bohne Phaseolus vulgaris). Vor dem Hintergrund der extrem heterogenen Wirkungen, die in der Literatur beschrieben werden, wurde eine systematische Analyse unter standardisierten Wachstumsbedingungen in Abhängigkeit der Pflanzenart, der MWCNT-Dosierung, der Dauer der MWCNT-Behandlung, und des pflanzlichen Entwicklungsstadiums durchgeführt. Kurzzeitige Saatgutbehandlungen mit MWCNTs (36 Std.) verminderten die Geschwindigkeit der Wasseraufnahme während der Einquellungsphase besonders bei Soja-Saatgut, was mit einer verbesserten Keimrate und einem verminderten Anteil abnorm entwickelter Keimlinge verbunden war. Während der weiteren Keimlings-entwicklung ergaben sich jedoch negative Wirkungen auf die Feinwurzelbildung bei allen untersuchten Pflanzenarten. Die Wurzelwachstumshemmung ging mit verminderter Stoffwechselaktivität im Wurzelgewebe und verminderter Nitrataufnahme einher, die hauptsächlich auf das schwächer entwickelte Wurzelsystem zurückzuführen war. Die Ergebnisse zeigen, dass selbst unter standardisierten Anzuchtbedingungen, die externe Einflussfaktoren weitestgehend ausschließen, unterschiedliche Wirkungen von MWCNTs in Abhängigkeit von der Pflanzenart, doch auch vom physiologischen Status und dem pflanzlichen Entwicklungsstadium, selbst bei individuellen Pflanzen auftreten können. Soja wurde in diesem Zusammenhang als Modellpflanze für weiterführende Studien ausgewählt, da hier sowohl positive als auch negative Wirkungen bei identischer MWCNT-Dosierung (1000 mg L-1) individuell an derselben Versuchspflanze auftraten. Kapitel 3 untersucht die Wirkungen kurzzeitiger MWCNT-Saatgutexposition (36 Std.) auf die Keimlingsentwicklung von Soja in Abhängigkeit der Nährstoffverfügbarkeit im Anzuchtsubstrat. Bereits acht Tage nach der Aussaat wurde erstmals gehemmtes Pflanzenwachstum und verminderte Feinwurzelentwicklung bei Keimlingen nachweisbar, die auf Keimpapier ohne weiteres Nährstoffangebot wuchsen. Dieser Hemmung ging eine, durch Vitalfärbung nachgewiesene Verminderung der Stoffwechselaktivität, bereits zwei Tage nach Aussaat voraus. Die resultierende Wurzelwachstumshemmung war jedoch ein langfristiger Effekt, der auch noch 38 Tage nach Aussaat bei Pflanzen in Bodenkultur nachweisbar war. Genauere Untersuchungen ergaben, dass Zink-(Zn)-Mangel einer der wichtigsten Wachstumslimitierenden Faktoren war. Das Wachstum von Pflanzen in Bodenkultur konnte durch Blattdüngung mit Zinksulfat regeneriert werden, während Zinksulfat-haltige Nährlösung in hydroponischer Kultur wirksam war. Eine detailiertere Analyse physiologischer Grundlagen der Hemmwirkung von MWCNTs auf das Pflanzenwachstum wird in Kapitel 4 vorgestellt: Oxidativer Stress wurde als Hauptfaktor für die MWCNT-induzierte Wurzelwachstums-hemmung bei Soja identifiziert, was durch die revertierende Wirkung der Supplementierung mit Antioxidantien auf das Wurzelwachstum bestätigt wurde. Die durch MWCNTs ausgelöste oxidative Stressreaktion war bereits innerhalb der 36-stündigen Saatgutquellungsperiode anhand der Akkumulation von Superoxid-Anionen, verminderter Vitalfärbung mit Triphenyltetrazoliumchlorid und erhöhter Aktivität der Superoxiddismutase (SOD) nachweisbar und erfasste besonders die Keimwurzelspitzen. Das Expressionsmuster dieser oxidativen Stressindikatoren spiegelte die präferentielle Akkumulation von MWCNTs in den Zellen der Wurzelspitze wider und konnte durch externe Applikation von Prolin als Antioxidant revertiert werden. Die MWCNT-induzierten Pflanzenschäden waren ebenso durch die Supplementierung mit Mikronährstoffen (Zn, Cu, Mn) revertierbar, die als wichtige Co-Faktoren für Enzymsysteme der oxidativen Stressabwehr fungieren (SOD, Synthese antioxidativer Phenole). Entsprechend konnte ein Anstieg der SOD Aktivität im Wurzelgewebe MWCNT-behandelter Keimlinge nach Zn Applikation nachgewiesen werden. Die MWCNT-Behandlung hemmte während der Keimung besonders die Zn-Translokation aus den Kotyledonen in die jungen, wachsenden Gewebe des Keimlings und MWCNTs zeigten ein selektives Adsorptionspotenzial besonders für Zn und Cu, das so an einer intrazellulären Immobilisierung dieser Mikronährstoffe beteiligt sein könnte. Damit zeigt die vorliegende Arbeit erstmals, dass die Phytotoxizität von CNTs mit Störungen der Mikronährstoffhomöostase während der Keimlingsentwicklung in Verbindung steht. Die Bedeutung für die Phytotoxizitätsbewertung von MWCNTs und ihrer potenziellen Anwendungen in der landwirtschaftlichen Praxis werden in einer Abschlussbetrachtung diskutiert (Kapitel 5)

Problems and mechanisms of sustainable development of rural areas (at the example of the Republic of Mordovia)

Sustainable development of rural areas is a priority in today's Russia, as evidenced by the system of regulations adopted in 2010-2015. Measures of government regulation aimed at ensuring food security and improving the living standards of the rural population include activities for the growth and modernization of agricultural production, development of the market of agricultural raw materials and food, as well as expansion and strengthening of the network of rural social infrastructure. These measures which are actively used since 2006, have failed to overcome the crisis processes in most regions, which indicates the need for revision of rural development policy. In the article the need for differentiation of government support in accordance with the typology of rural areas, considering the potential and the level of social, economic and environmental development is argued. The system of indicators and an integrated approach to assessing the sustainability of rural areas are suggested. The proposals for additional measures to support the depressed rural areas are suggested.peer-reviewe

The Ecdysone receptor constrains wingless expression to pattern cell cycle across the Drosophila wing margin in a cyclin B-dependent manner

Background: Ecdysone triggers transcriptional changes via the ecdysone receptor (EcR) to coordinate developmental programs of apoptosis, cell cycle and differentiation. Data suggests EcR affects cell cycle gene expression indirectly and here we identify Wingless as an intermediary factor linking EcR to cell cycle. Results: We demonstrate EcR patterns cell cycle across the presumptive Drosophila wing margin by constraining wg transcription to modulate CycB expression, but not the previously identified Wg-targets dMyc or Stg. Furthermore co-knockdown of Wg restores CycB patterning in EcR knockdown clones. Wg is not a direct target of EcR, rather we demonstrate that repression of Wg by EcR is likely mediated by direct interaction between the EcR-responsive zinc finger transcription factor Crol and the wg promoter. Conclusions: Thus we elucidate a critical mechanism potentially connecting ecdysone with patterning signals to ensure correct timing of cell cycle exit and differentiation during margin wing development

Vocal development during postnatal growth and ear morphology in a shrew that generates seismic vibrations, Diplomesodon pulchellum.

The ability of adult and subadult piebald shrews (Diplomesodon pulchellum) to produce 160Hz seismic waves is potentially reflected in their vocal ontogeny and ear morphology. In this study, the ontogeny of call variables and body traits was examined in 11 litters of piebald shrews, in two-day intervals from birth to 22 days (subadult), and ear structure was investigated in two specimens using micro-computed tomography (micro-CT). Across ages, the call fundamental frequency (f0) was stable in squeaks and clicks and increased steadily in screeches, representing an unusual, non-descending ontogenetic pathway of f0. The rate of the deep sinusoidal modulation (pulse rate) of screeches increased from 75Hz at 3-4 days to 138Hz at 21-22 days, probably relating to ontogenetic changes in contraction rates of the same muscles which are responsible for generating seismic vibrations. The ear reconstructions revealed that the morphologies of the middle and inner ears of the piebald shrew are very similar to those of the common shrew (Sorex araneus) and the lesser white-toothed shrew (Crocidura suaveolens), which are not known to produce seismic signals. These results suggest that piebald shrews use a mechanism other than hearing for perceiving seismic vibrations.This study was supported by the Russian Scientific Foundation, grant No 14-14-00237 (for IV, AZ and EV).This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.beproc.2015.06.01

SPATIAL ORGANIZATION OF INDUSTRIAL TOURISM OBJECTS: CASE OF THE KEMEROVO REGION – KUZBASS

In recent years, the industrialized regions of Russia have faced the need to diversify the economy and develop new industries. The advantage of such regions is that they can use their industrial heritage to develop primarily industrial tourism. The purpose of the article is to analyze the spatial organization of industrial tourism objects on the territory of the Kemerovo region – Kuzbass. The authors analyze the approaches to the essence of the concept of "industrial tourism", study international and Russian experience in the development of industrial areas and assess the state of industrial tourism in the region with the help of SWOT-analysis method. Authors also identify the potential objects of industrial tourism and analyze their spatial organization. With the help of the QGIS 3.20 program, thematic map-scheme of the location of industrial tourism objects has been made. The conclusions about the prospects and directions of development of industrial tourism in the Kemerovo region – Kuzbass are made

Дослідження переробки нікель-кобальтвмісних металургійних відходів екологічно безпечним способом водневого відновлення

We studied kinetic patterns of hydrogen reduction of the scale of a nickel-cobalt containing precision alloy at a temperature of 673‒1573 K over a period from 0 to 180 minutes. The highest degree of reduction was achieved after thermal treatment at 1273 K – 99 %. This is predetermined by the intensification of reduction processes and a sufficient level of porosity, which ensures satisfactory gas exchange. It was discovered that the starting scale consists mainly of Fe3O4, Fe2O3 and FeO with atoms substituting their alloying elements. The target product of metallization had a sponge-like microstructure and consisted mainly of the solid solution of Co and Ni atoms in γ-Fe and the residual non-reduced Fe3O4 and FeO. The resulting phases had no noticeable susceptibility to sublimation.This has ensured a reduction in the losses of alloying elements while receiving and using the highly-alloyed metallized scale, which was confirmed by experimental- industrial tests. At the same time, recycling of industrial wastes contributes to a reduction in the technogenic intensity of industrial regions and improves ecological safety of the environmentИсследована кинетика водородного восстановления окалины никель-кобальтсодержащего прецизионного сплава. Целевой продукт металлизации после восстановления при 1273 K имел губчатую микроструктуру, преимущественно состоял из твердого раствора атомов Ni и Co в γ–Fe. Также выявлен остаток Fe3O4 и FeO. Опытно-промышленные испытания подтвердили эффективность использования новой легирующей добавки с параллельной утилизацией техногенных отходовДослідженно кінетику водневого відновлення окалини нікель-кобальтвмісного прецизійного сплаву. Цільовий продукт металізації після відновлення при 1273 K мав губчасту мікроструктуру, переважно складався з твердого розчину атомів Ni та Co в γ–Fe. Також виявлено залишок Fe3O4 та FeO. Дослідно-промислові випробування підтвердили ефективність використання нової легуючої добавки з паралельною утилізацією техногенних відході

Ontogenetic Development of Neurophysiological Mechanisms Underlying Language Processing

During the last 20 years, new data on the neurophysiological mechanisms underlying different types of cognitive activity, especially speech and its ontogenetic formation, were obtained in the Laboratory of Children’s Neurophysiology headed by Prof. M.N. Tsitseroshin. Using the analysis of the spatial-temporal structure of regional interactions of cortical bioelectric potentials (so-called functional connectivity), we investigated how specific language levels, such as phonology, grammar, and semantics, are represented in the brain. The data obtained in children vs. adults indicate that the speech perception and production require joint and extremely coordinated activities of both hemispheres, along with the obligatory and differentiated involvement of “classic” speech centers in the left hemisphere, especially Wernicke’s area. Another line of our research is to explore the differences, which arise during verbal processing in adults and children with impaired vs. non-impaired speech, particularly with alalia, dysarthria and stuttering, using behavioral and EEG data. Our data obtained in children vs. adults allow assessing the degree of maturity in the organization of the central processes of maintaining the studied types of verbal activity in children of different ages. These data allow expanding modern concepts about the brain mechanisms of verbal activity in children in the norm and pathology

Glial-Specific Functions of Microcephaly Protein WDR62 and Interaction with the Mitotic Kinase AURKA Are Essential for Drosophila Brain Growth

The second most commonly mutated gene in primary microcephaly (MCPH) patients is wd40-repeat protein 62 (wdr62), but the relative contribution of WDR62 function to the growth of major brain lineages is unknown. Here, we use Drosophila models to dissect lineagespecific WDR62 function(s). Interestingly, although neural stem cell (neuroblast)-specific depletion of WDR62 significantly decreased neuroblast number, brain size was unchanged. In contrast, glial lineage-specific WDR62 depletion significantly decreased brain volume. Moreover, loss of function in glia not only decreased the glial population but also non-autonomously caused neuroblast loss.We further demonstrated that WDR62 controls brain growth through lineage-specific interactions with master mitotic signaling kinase, AURKA. Depletion of AURKA in neuroblasts drives brain overgrowth, which was suppressed by WDR62 co-depletion. In contrast, glial-specific depletion of AURKA significantly decreased brain volume, which was further decreased by WDR62 co-depletion. Thus, dissecting relative contributions of MCPH factors to individual neural lineages will be critical for understanding complex diseases such as microcephaly

Minimal B Cell Extrinsic IgG Glycan Modifications of Pro- and Anti-Inflammatory IgG Preparations in vivo

Select residues in the biantennary sugar moiety attached to the fragment crystallizable of immunoglobulin G (IgG) antibodies can modulate IgG effector functions. Thus, afucosylated IgG glycovariants have enhanced cytotoxic activity, whereas IgG glycovariants rich in terminal sialic acid residues can trigger anti-inflammatory effects. More recent evidence suggests that terminal α2,6 linked sialic acids can be attached to antibodies post IgG secretion. These findings raise concerns for the use of therapeutic antibodies as they may change their glycosylation status in the patient and hence affect their activity. To investigate to what extent B cell extrinsic sialylation processes modify therapeutic IgG preparations in vivo, we analyzed changes in human intravenous IgG (IVIg) sialylation upon injection in mice deficient in B cells or in mice lacking the sialyltransferase 1, which catalyzes the addition of α2,6 linked sialic acid residues. By performing a time course of IgG glycan analysis with HILIC-UPLC-FLR (plus MS) and xCGE-LIF our study suggests that therapeutic IgG glycosylation is stable upon injection in vivo. Only a very small fraction of IgG molecules acquired sialic acid structures predominantly in the Fab- but not the Fc-portion upon injection in vivo, suggesting that therapeutic antibody glycosylation will remain stable upon injection in vivo