Hotspots of microbial activity induced by earthworm burrows,old root channels,and their combination in subsoil     

Duyen T. T. Hoang  Johanna Pausch  Bahar S. Razavi  Irina Kuzyakova  Callum C. Banfield  Yakov Kuzyakov 《Biology and Fertility of Soils》2016,52(8):1105-1119

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Adaptation to Change and Re-designing of Governance Systems: Cases from Small-Scale Rural Forestry     

Irina Kouplevatskaya-Buttoud 《Small-Scale Forestry》2009,8(2):231-247

Changes in small-scale forest governance as a reaction to global changes are viewed from the system dynamics perspective, focused on two levels of dynamic systems: the policy system with sets of interactions at the national level and the management system at the local level. These interactions are considered through permanent adaptation and re-shaping of stakeholders’ networks and positions provoking further changes in the systems. Empirical evidence has been obtained from two case studies related to small-scale rural forestry in distinct contexts—France (the Territorial Forestry Charters) and Kyrgyzstan (collaborative forest management and leasing of forest plots)—and viewed through a theoretical framework of social-political systems dynamics. The changes caused by the systems’ capacity for adaptability and resilience are expressed through a double spiral of decision-making, characterising the interactions between national policies and local management practices. The analysis leads to a conclusion that changes are basically determined by the formal and informal stakeholders’ strategies developed in a specific context and their mutual adaptation aimed at system resilience.

Irina Kouplevatskaya-ButtoudEmail:

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Bromine Accumulation in Some Crops and Grasses as Determined by Neutron Activation Analysis     

Irina Shtangeeva 《Communications in Soil Science and Plant Analysis》2017,48(19):2338-2346

Till now information on bromine (Br) in the environment is still incomplete. The purposes of this research were the following: to study accumulation of Br in plants grown under different environmental conditions and to assess the factors controlling Br uptake by different plant species when the plants grow in soil uncontaminated with Br. For the determination of Br and other elements, neutron activation analysis was used. This method allows for determining a wide range of elements in various samples with high sensitivity and accuracy. Model tests and greenhouse experiments demonstrated different abilities of plants to uptake Br from various media and transfer it from roots to upper plant parts. It was shown that the main source of Br for a plant was soil. As a result of the plant growth concentration of Br in the rhizosphere soil decreased. The characteristics of soil have a pronounced effect on the Br uptake by plants.  相似文献   

A one-stage model of experimental acute necrotizing pancreatitis in rats     

SARAPULTSEV Alexey  RANTSEV Maxim  SARAPULTSEV Petr  MEDVEDEVA Svetlana  DANILOVA Irina 《园艺学报》2013,29(10):1870-1876

AIM: To establish a one-stage model of experimental acute necrotizing pancreatitis (ANP) in rats characterized by the simplicity of performance and a high degree of repeatability. METHODS: ANP modeling in rats was performed based on modification of the ligation model as follows: synthetic material ligature using an atraumatic needle was performed to capture pancreatic gland ducts and marginal duodenum vessels. Ligature tips were exteriorized to the abdominal wall, and the ligature was skinned over to avoid catching intestine loops. Pancreatic macroscopic appearance and histological changes were observed. Blood biochemical and hemostatic indicators were also determined. RESULTS: Laboratory analysis of rats with experimental ANP showed a pattern of disturbances similar to that observed during pancreatic necrosis in humans as soon as the first day. General blood analysis revealed enhanced leukocytosis and alterations in leukogram characteristics, indicating acute inflammation. Serum levels of amylase, aspartate aminotransferase and creatinine significantly increased (P<0.05). Hemostatic indicators showed alterations indicating formation of disseminated intravascular coagulation, and signs of endotoxicosis were observed. These typical pancreatic necrosis patterns of disturbances were validated by the results of histological investigation. CONCLUSION: Histological changes and laboratory indicators confirm the development of a suitable model of ANP.  相似文献   

Chemical analysis of Teucrium species (Lamiaceae) growing on serpentine soils in Bulgaria     

Dolja Pavlova  Irina Karadjova 《植物养料与土壤学杂志》2012,175(6):891-899

Trace elemental concentrations (Fe, Ni, Mn, Cr, Co, Cu, Zn, Pb, Cd, and As) in aerial biomass (stems, leaves, and flowers) of the medicinal plants Teucrium chamaedrys, T. montanum, and T. polium growing on serpentine soils in Bulgaria were examined in relation to the total element contents in their respective rhizospheric soils. The objectives of the study were to evaluate: (1) elemental concentrations in plant tissues and associated soil samples together with the plants ability to tolerate/accumulate metal concentrations; (2) correlations between total metal concentrations in plants and their rhizospheric soils. Metal concentrations varied across species and sites. Their levels in plant tissues from nonserpentine sites were always lower compared to those from serpentine ones. The highest concentrations for Fe, Ni, Mn, Cr, As, Cu, and Pb were found in T. polium. Positive correlation coefficients were established between Ni, Cr, Fe, Co, and Cu in plants and Ca in the soil. None of the species tested hyperaccumulated metals although the metal concentration in some of them exceeded the range naturally found in plants. The Teucrium species can be considered as “excluders”, containing relatively low metal concentrations in their aerial parts (stems, leaves, and flowers) even in cases of high elemental concentrations in the rhizospheric soil. In all three medicinal plants, metal concentrations for toxic elements were above the permissible limits for pharmaceutical purposes. Therefore, plants found on serpentine bedrock are not recommended to be collected for pharmaceutical purposes.  相似文献   

Nature-inspired soluble iron-rich humic compounds: new look at the structure and properties     

Tatiana A. Sorkina  Alexander Yu. Polyakov  Natalia A. Kulikova  Anastasia E. Goldt  Olga I. Philippova  Alina A. Aseeva  Alexey A. Veligzhanin  Yan V. Zubavichus  Denis A. Pankratov  Eugene A. Goodilin  Irina V. Perminova 《Journal of Soils and Sediments》2014,14(2):261-268

Purpose

Humic substances (HS) being natural polyelectrolyte macromolecules with complex and disordered molecular structures are a key component of the terrestrial ecosystem. They have remarkable influence on environmental behavior of iron, the essential nutrient for plants. They might be considered as environmental friendly iron deficiency correctors free of synthetic iron (III) chelates disadvantages. The main goal of this study was to obtain water-soluble iron-rich humic compounds (IRHCs) and to evaluate their efficiency as chlorosis correctors.

Materials and methods

A facile preparation technique of IRHCs based on low-cost and available parent material was developed. The iron-containing precursor (ferrous sulfate) was added dropwisely into alkaline potassium humate solution under vigorous stirring and pH-control. A detailed characterization both of organic and inorganic parts of the compounds was provided, the iron species identification was carried out jointly by EXAFS and Mössbauer spectroscopy. Bioassay experiments were performed using cucumber Cucumis sativus L. as target plants. Plants were grown in modified Hoagland nutrient solution, prepared on deionized water and containing iron in the form of IRHCs. Total iron content in dry plants measured by spectrophotometry after oxidative digestion and the chlorophyll a content determined after acetone extraction from fresh plant were used as parameters illustrating plants functional status under iron deficiency condition.

Results and discussion

The high solubility (up to130 g/l) and iron content (about 11 wt%) of the IRHCs obtained allow considering them to be perspective for practical applications. A set of analytical methods has shown that the main iron species in IRHCs are finely dispersed iron (III) oxide and hydroxide nanoparticles. An application of the precursor solution acidification allows to obtain compounds containing a significant part of total iron (up to 30 %) in the form of partly disordered iron (II–III) hydroxysulphate green rust GR(SO₄ ^2?). Bioavailability of iron from IRHCs was demonstrated using bioassay in cucumber plants grown up on hydroponics under iron deficiency conditions.

Conclusions

The application of iron oxides chemistry for humic substance containing solution was proved to be an effective approach to synthesis of IRHCs. Using bioassay on cucumber plants C. sativus L. under iron deficiency conditions, the efficiency of compounds obtained as chlorosis correctors was demonstrated. Application of water-soluble IRHCs led to significant increase of chlorophyll a content (up to 415 % of the blank) and iron content in plants (up to 364 % of the blank) grown up on hydroponics.  相似文献   

Effects of bromides of potassium and ammonium on some crops     

Irina Shtangeeva  Matti Niemelä  Paavo Perämäki 《Journal of plant nutrition》2013,36(18):2209-2220

In this work, the response of wheat (Triticum aestivum L.), rye (Secale cereale L.), oat (Avena sativa L.), and pea (Pisum sativum L.) to bromides of potassium (KBr) and ammonium (NH₄Br) was studied. All plants were capable of accumulating high concentrations of bromine (Br). However, the Br accumulation depended on the Br compounds presented in the growth medium and plant species. The highest Br concentrations were observed in leaves and roots of the seedlings germinated in the medium spiked with KBr. Oat accumulated more Br than other plants and the lowest Br accumulation was observed in pea. The bioaccumulation of Br resulted in suppression of plant biomass and concentrations of several essential nutrients (K, Na, Ca, Mg, Zn and Cl). The most negative effects were caused by NH₄Br. Probably, this action was due to cumulative effects of Br^- and NH₄⁺. Among other plant species, the most tolerant to bromides was oat and the most sensitive was wheat.  相似文献   

Influence of the Structural Features of Carrageenans from Red Algae of the Far Eastern Seas on Their Antiviral Properties     

Natalia V. Krylova  Anna O. Kravchenko  Olga V. Iunikhina  Anastasia B. Pott  Galina N. Likhatskaya  Aleksandra V. Volod&#x;ko  Tatyana S. Zaporozhets  Mikhail Y. Shchelkanov  Irina M. Yermak 《Marine drugs》2022,20(1)

The structural diversity and unique physicochemical properties of sulphated polysaccharides of red algae carrageenans (CRGs), to a great extent, determine the wide range of their antiviral properties. This work aimed to compare the antiviral activities of different structural types of CRGs: against herpes simplex virus type 1 (HSV-1) and enterovirus (ECHO-1). We found that CRGs significantly increased the resistance of Vero cells to virus infection (preventive effect), directly affected virus particles (virucidal effect), inhibited the attachment and penetration of virus to cells, and were more effective against HSV-1. CRG1 showed the highest virucidal effect on HSV-1 particles with a selective index (SI) of 100. CRG2 exhibited the highest antiviral activity by inhibiting HSV-1 and ECHO-1 plaque formation, with a SI of 110 and 59, respectively, when it was added before virus infection. CRG2 also significantly reduced the attachment of HSV-1 and ECHO-1 to cells compared to other CRGs. It was shown by molecular docking that tetrasaccharides—CRGs are able to bind with the HSV-1 surface glycoprotein, gD, to prevent virus–cell interactions. The revealed differences in the effect of CRGs on different stages of the lifecycle of the viruses are apparently related to the structural features of the investigated compounds.  相似文献   

AsKC11, a Kunitz Peptide from Anemonia sulcata,Is a Novel Activator of G Protein-Coupled Inward-Rectifier Potassium Channels     

Dongchen An  Ernesto Lopes Pinheiro-Junior  Lszl Bress  Irina Gladkikh  Elena Leychenko  Eivind A. B. Undheim  Steve Peigneur  Jan Tytgat 《Marine drugs》2022,20(2)

(1) Background: G protein-coupled inward-rectifier potassium (GIRK) channels, especially neuronal GIRK1/2 channels, have been the focus of intense research interest for developing drugs against brain diseases. In this context, venom peptides that selectively activate GIRK channels can be seen as a new source for drug development. Here, we report on the identification and electrophysiological characterization of a novel activator of GIRK1/2 channels, AsKC11, found in the venom of the sea anemone Anemonia sulcata. (2) Methods: AsKC11 was purified from the sea anemone venom by reverse-phase chromatography and the sequence was identified by mass spectrometry. Using the two-electrode voltage-clamp technique, the activity of AsKC11 on GIRK1/2 channels was studied and its selectivity for other potassium channels was investigated. (3) Results: AsKC11, a Kunitz peptide found in the venom of A. sulcata, is the first peptide shown to directly activate neuronal GIRK1/2 channels independent from Gi/o protein activity, without affecting the inward-rectifier potassium channel (IRK1) and with only a minor effect on K_V1.6 channels. Thus, AsKC11 is a novel activator of GIRK channels resulting in larger K⁺ currents because of an increased chord conductance. (4) Conclusions: These discoveries provide new insights into a novel class of GIRK activators.  相似文献   

A Tale of Toxin Promiscuity: The Versatile Pharmacological Effects of Hcr 1b-2 Sea Anemone Peptide on Voltage-Gated Ion Channels     

Ernesto Lopes Pinheiro-Junior  Rimma Kalina  Irina Gladkikh  Elena Leychenko  Jan Tytgat  Steve Peigneur 《Marine drugs》2022,20(2)

Sea anemones are a rich source of biologically active compounds. Among approximately 1100 species described so far, Heteractis crispa species, also known as sebae anemone, is native to the Indo-Pacific area. As part of its venom components, the Hcr 1b-2 peptide was first described as an ASIC1a and ASIC3 inhibitor. Using Xenopus laevis oocytes and the two-electrode voltage-clamp technique, in the present work we describe the remarkable lack of selectivity of this toxin. Besides the acid-sensing ion channels previously described, we identified 26 new targets of this peptide, comprising 14 voltage-gated potassium channels, 9 voltage-gated sodium channels, and 3 voltage-gated calcium channels. Among them, Hcr 1b-2 is the first sea anemone peptide described to interact with isoforms from the Kv7 family and T-type Cav channels. Taken together, the diversity of Hcr 1b-2 targets turns this toxin into an interesting tool to study different types of ion channels, as well as a prototype to develop new and more specific ion channel ligands.  相似文献