Готові списки джерел за темами / Metal ion import

Добірка наукової літератури з теми "Metal ion import"

Автор: Grafiati
Опубліковано: 10 грудня 2022
Оновлено: 29 січня 2023

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Статті в журналах з теми "Metal ion import"

1

Neville, Stephanie L., Jennie Sjöhamn, Jacinta A. Watts, Hugo MacDermott-Opeskin, Stephen J. Fairweather, Katherine Ganio, Alex Carey Hulyer, et al. "The structural basis of bacterial manganese import." Science Advances 7, no. 32 (August 2021): eabg3980. http://dx.doi.org/10.1126/sciadv.abg3980.

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Анотація:
Metal ions are essential for all forms of life. In prokaryotes, ATP-binding cassette (ABC) permeases serve as the primary import pathway for many micronutrients including the first-row transition metal manganese. However, the structural features of ionic metal transporting ABC permeases have remained undefined. Here, we present the crystal structure of the manganese transporter PsaBC from Streptococcus pneumoniae in an open-inward conformation. The type II transporter has a tightly closed transmembrane channel due to “extracellular gating” residues that prevent water permeation or ion reflux. Below these residues, the channel contains a hitherto unreported metal coordination site, which is essential for manganese translocation. Mutagenesis of the extracellular gate perturbs manganese uptake, while coordination site mutagenesis abolishes import. These structural features are highly conserved in metal-specific ABC transporters and are represented throughout the kingdoms of life. Collectively, our results define the structure of PsaBC and reveal the features required for divalent cation transport.
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2

F. M. Cellier, Mathieu. "Evolutionary analysis of Slc11 mechanism of proton-coupled metal-ion transmembrane import." AIMS Biophysics 3, no. 2 (2016): 286–318. http://dx.doi.org/10.3934/biophy.2016.2.286.

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3

Camponeschi, Francesca, and Lucia Banci. "Metal cofactors trafficking and assembly in the cell: a molecular view." Pure and Applied Chemistry 91, no. 2 (February 25, 2019): 231–45. http://dx.doi.org/10.1515/pac-2018-0720.

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Abstract Metal ions are essential cofactors required by the proteome of organisms from any kingdom of life to correctly exert their functions. Dedicated cellular import, transport and homeostasis systems assure that the needed metal ion is correctly delivered and inserted into the target proteins and avoid the presence of free metal ions in the cell, preventing oxidative damaging. Among metal ions, in eukaryotic organisms copper and iron are required by proteins involved in absolutely essential functions, such as respiration, oxidative stress protection, catalysis, gene expression regulation. Copper and iron binding proteins are localized in essentially all cellular compartments. Copper is physiologically present mainly as individual metal ion. Iron can be present both as individual metal ion or as part of cofactors, such as hemes and iron-sulfur (Fe-S) clusters. Both metal ions are characterized by the ability to cycle between different oxidation states, which enable them to catalyze redox reactions and to participate in electron transfer processes. Here we describe in detail the main processes responsible for the trafficking of copper and iron sulfur clusters, with particular interest for the structural aspects of the maturation of copper and iron-sulfur-binding proteins.
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4

Jakubovics, Nicholas S. "An ion for an iron: streptococcal metal homeostasis under oxidative stress." Biochemical Journal 476, no. 4 (February 28, 2019): 699–703. http://dx.doi.org/10.1042/bcj20190017.

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Abstract The ability of opportunistic pathogens such as Group A Streptococcus (GAS) to transition between mucosal colonisation and invasive disease requires complex systems for adapting to markedly different host environments. The battle to acquire essential trace metals such as manganese and iron from the host is central to pathogenesis. Using a molecular genetic approach, Turner et al. [Biochem. J. (2019) 476, 595–611] show that it is not just individual metal concentrations that are important, but the ratio of iron to manganese within cells. Increasing this ratio by knocking out pmtA, encoding the Fe(II) exporter PmtA, or by disrupting mtsA, encoding an MtsABC Mn(II)-import system component, led to reductions in superoxide dismutase (SodA) activity and increased sensitivity to oxidative stress. The authors show that SodA is at least 4-fold more active with Mn bound than with Fe and speculate that high intracellular Fe:Mn ratios reduce superoxide dismutase activity through the mismetalation of SodA. Challenging wild-type GAS with 1 mM H2O2 led to a decrease in Fe:Mn ratio and a 3-fold increase in SodA activity, indicating that modulation of the balance between intracellular Fe and Mn may play an important role in adaptation to oxidative stress. This work unravels some of the key mechanisms for maintaining appropriate Mn and Fe concentrations within bacterial cells and underscores the need for future studies that take an holistic view to metal ion homeostasis in bacteria. Strategies aimed at interfering with the balance of intracellular metal ions represent a promising approach for the control of invasive microbial infections.
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5

Chi, N. C., E. J. Adam, and S. A. Adam. "Sequence and characterization of cytoplasmic nuclear protein import factor p97." Journal of Cell Biology 130, no. 2 (July 15, 1995): 265–74. http://dx.doi.org/10.1083/jcb.130.2.265.

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Nuclear location sequence-mediated binding of karyophilic proteins to the nuclear pore complexes is one of the earliest steps in nuclear protein import. We previously identified two cytosolic proteins that reconstitute this step in a permeabilized cell assay: the 54/56-kD NLS receptor and p97. A monoclonal antibody to p97 localizes the protein to the cytoplasm and the nuclear envelope. p97 is extracted from nuclear envelopes under the same conditions as the O-glycosylated nucleoporins indicating a tight association with the pore complex. The antibody inhibits import in a permeabilized cell assay but does not affect binding of karyophiles to the nuclear pore complex. Immunodepletion of p97 renders the cytosol inactive for import and identifies at least three other cytosolic proteins that interact with p97. cDNA cloning of p97 shows that it is a unique protein containing 23 cysteine residues. Recombinant p97 binds zinc and a bound metal ion is required for the nuclear envelope binding activity of the protein.
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6

Froschauer, Elisabeth M., Nicole Rietzschel, Melanie R. Hassler, Markus Binder, Rudolf J. Schweyen, Roland Lill, Ulrich Mühlenhoff, and Gerlinde Wiesenberger. "The mitochondrial carrier Rim2 co-imports pyrimidine nucleotides and iron." Biochemical Journal 455, no. 1 (September 13, 2013): 57–65. http://dx.doi.org/10.1042/bj20130144.

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Mitochondrial iron uptake is of key importance both for organelle function and cellular iron homoeostasis. The mitochondrial carrier family members Mrs3 and Mrs4 (homologues of vertebrate mitoferrin) function in organellar iron supply, yet other low efficiency transporters may exist. In Saccharomyces cerevisiae, overexpression of RIM2 (MRS12) encoding a mitochondrial pyrimidine nucleotide transporter can overcome the iron-related phenotypes of strains lacking both MRS3 and MRS4. In the present study we show by in vitro transport studies that Rim2 mediates the transport of iron and other divalent metal ions across the mitochondrial inner membrane in a pyrimidine nucleotide-dependent fashion. Mutations in the proposed substrate-binding site of Rim2 prevent both pyrimidine nucleotide and divalent ion transport. These results document that Rim2 catalyses the co-import of pyrimidine nucleotides and divalent metal ions including ferrous iron. The deletion of RIM2 alone has no significant effect on mitochondrial iron supply, Fe–S protein maturation and haem synthesis. However, RIM2 deletion in mrs3/4Δ cells aggravates their Fe–S protein maturation defect. We conclude that under normal physiological conditions Rim2 does not play a significant role in mitochondrial iron acquisition, yet, in the absence of the main iron transporters Mrs3 and Mrs4, this carrier can supply the mitochondrial matrix with iron in a pyrimidine-nucleotide-dependent fashion.
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7

Lewicka, Ewa, Katarzyna Guzik, and Krzysztof Galos. "On the Possibilities of Critical Raw Materials Production from the EU’s Primary Sources." Resources 10, no. 5 (May 17, 2021): 50. http://dx.doi.org/10.3390/resources10050050.

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Анотація:
Sufficient supplies of critical raw materials (CRMs) for rapidly developing technologies, e.g., Li-ion batteries, wind turbines, photovoltaics, digitization, etc., have become one of the main economic challenges for the EU. Due to growing import dependency and associated risk of supply disruptions of these raw materials from third countries, there is a need to encourage their domestic production. This is an important starting point for EU value chains crucial for the sustainable economic growth of the whole Union. This contribution has evaluated the possibilities of CRMs supply from the EU’s primary sources. A three-step approach, including an assessment of CRMs’ importance for the EU’s economic growth, their significance in at least two of the three strategic industrial sectors (i.e., renewable energy, e-mobility, defense and aerospace), and their potential availability from EU mineral deposits, has been applied. Results of the analysis have shown that, of 29 critical mineral raw materials (according to the 2020 EC list), the potential to develop manufacturing from the Union mineral deposits exists for 11 CRMs, i.e., cobalt, graphite (natural), HREE, LREE, lithium, magnesium, niobium, PGMs, silicon metal, titanium, and tungsten, while some other CRMs, namely gallium, germanium, indium, and vanadium can be recovered as by-products. Measures to mitigate EU import dependency have been also proposed.
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8

Foot, Natalie J., Yew Ann Leong, Loretta E. Dorstyn, Hazel E. Dalton, Kristen Ho, Lin Zhao, Michael D. Garrick, Baoli Yang, Devendra Hiwase, and Sharad Kumar. "Ndfip1-deficient mice have impaired DMT1 regulation and iron homeostasis." Blood 117, no. 2 (January 13, 2011): 638–46. http://dx.doi.org/10.1182/blood-2010-07-295287.

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Abstract The divalent metal ion transporter DMT1 is critical for nonheme iron import. We have previously shown that DMT1 is regulated in vitro by ubiquitination that is facilitated by the adaptor proteins Ndfip1 and Ndfip2. Here we report that in Ndfip1−/− mice fed a low- iron diet, DMT1 expression and activity in duodenal enterocytes are significant higher than in the wild-type animals. This correlates with an increase in serum iron levels and transferrin saturation. Liver and spleen iron stores were also increased in Ndfip1−/− mice fed a normal diet. Counterintuitive to the increase in iron uptake, Ndfip1−/− mice fed a low iron diet develop severe microcytic, hypochromic anemia. We demonstrate that this is due to a combination of iron deficiency and inflammatory disease in Ndfip1−/− mice, because Ndfip1−/−/Rag1−/− immunodeficient mice fed a low iron diet did not develop anemia and showed an iron overload phenotype. These data demonstrate that Ndfip1 is a critical mediator of DMT1 regulation in vivo, particularly under iron restricted conditions.
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9

Krenn, B. M., E. Gaudernak, B. Holzer, K. Lanke, F. J. M. Van Kuppeveld, and J. Seipelt. "Antiviral Activity of the Zinc Ionophores Pyrithione and Hinokitiol against Picornavirus Infections." Journal of Virology 83, no. 1 (October 15, 2008): 58–64. http://dx.doi.org/10.1128/jvi.01543-08.

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ABSTRACT We have discovered two metal ion binding compounds, pyrithione (PT) and hinokitiol (HK), that efficiently inhibit human rhinovirus, coxsackievirus, and mengovirus multiplication. Early stages of virus infection are unaffected by these compounds. However, the cleavage of the cellular eukaryotic translation initiation factor eIF4GI by the rhinoviral 2A protease was abolished in the presence of PT and HK. We further show that these compounds inhibit picornavirus replication by interfering with proper processing of the viral polyprotein. In addition, we provide evidence that these structurally unrelated compounds lead to a rapid import of extracellular zinc ions into cells. Imported Zn2+ was found to be localized in punctate structures, as well as in mitochondria. The observed elevated level of zinc ions was reversible when the compounds were removed. As the antiviral activity of these compounds requires the continuous presence of the zinc ionophore PT, HK, or pyrrolidine-dithiocarbamate, the requirement for zinc ions for the antiviral activity is further substantiated. Therefore, an increase in intracellular zinc levels provides the basis for a new antipicornavirus mechanism.
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Lasorsa, Alessia, Giovanni Natile, Antonio Rosato, Francesco Tadini-Buoninsegni, and Fabio Arnesano. "Monitoring Interactions Inside Cells by Advanced Spectroscopies: Overview of Copper Transporters and Cisplatin." Current Medicinal Chemistry 25, no. 4 (February 12, 2018): 462–77. http://dx.doi.org/10.2174/0929867324666171110141311.

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Анотація:
Background: Resistance, either at the onset of the treatment or developed after an initial positive response, is a major limitation of antitumor therapy. In the case of platinum- based drugs, copper transporters have been found to interfere with drug trafficking by facilitating the import or favoring the platinum export and inactivation. Methods: The use of powerful spectroscopic, spectrometric and computational methods has allowed a deep structural insight into the mode of interaction of platinum drugs with the metal-binding domains of the transporter proteins. Results: This review article focuses on the mode in which platinum drugs can compete with copper ion for binding to transport proteins and consequent structural and biological effects. Three types of transporters are discussed in detail: copper transporter 1 (Ctr1), the major responsible for Cu+ uptake; antioxidant-1 copper chaperone (Atox1), responsible for copper transfer within the cytoplasm; and copper ATPases (ATP7A/B), responsible for copper export into specific subcellular compartments and outside the cell. Conclusion: The body of knowledge summarized in this review can help in shaping current chemotherapy to optimize the efficacy of platinum drugs (particularly in relation to resistance) and to mitigate adverse effects on copper metabolism.
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Більше джерел

Дисертації з теми "Metal ion import"

1

Wei, Shiqiang. "Metal ion interactions in the environment /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5495-6.pdf.

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2

Noakes, Timothy Charles Quentin. "Coaxial impact collision ion scattering spectroscopy of semiconductor and metal surfaces." Thesis, University of Warwick, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308005.

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3

Adamovic, Dragan. "Molecular Dynamics Studies of Low-Energy Atom Impact Phenomena on Metal Surfaces during Crystal Growth." Doctoral thesis, Linköpings universitet, Teoretisk Fysik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7165.

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It is a well-known fact in the materials science community that the use of low-energy atom impacts during thin film deposition is an effective tool for altering the growth behavior and for increasing the crystallinity of the films. However, the manner in which the incident atoms affect the growth kinetics and surface morphology is quite complicated and still not fully understood. This provides a strong incentive for further investigations of the interaction among incident atoms and surface atoms on the atomic scale. These impact-induced energetic events are non-equilibrium, transient processes which complete in picoseconds. The only accessible technique today which permits direct observation of these events is molecular dynamics (MD) simulations. This thesis deals with MD simulations of low-energy atom impact phenomena on metal surfaces during crystal growth. Platinum is chosen as a model system given that it has seen extended use as a model surface over the past few decades, both in experiments and simulations. In MD, the classical equations of motion are solved numerically for a set of interacting atoms. The atomic interactions are calculated using the embedded atom method (EAM). The EAM is a semi-empirical, pair-functional interatomic potential based on density functional theory. This potential provides a physical picture that includes many-atom effects while retaining computational efficiency needed for larger systems. Single adatoms residing on a surface constitute the smallest possible clusters and are the fundamental components controlling nucleation kinetics. Small two-dimensional clusters on a surface are the result of nucleation and are present during the early stages of growth. These surface structures are chosen as targets in the simulations (papers I and II) to provide further knowledge of the atomistic processes which occur during deposition, to investigate at which impact energies the different kinetic pathways open up, and how they may affect growth behavior. Some of the events observed are adatom scattering, dimer formation, cluster disruption, formation of three-dimensional clusters, and residual vacancy formation. Given the knowledge obtained, papers III and IV deal with growth of several layers with the aim to study the underlying mechanisms responsible for altering growth behavior and how the overall intra- and interlayer atomic migration can be controlled by low-energy atom impacts.

On the day of the defence date the status of article II was Accepted.

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4

BANOUNI, MOSTAFA. "Effets de la topographie de surface induite par impact d'ions lourds sur la spectrometrie d'electrons secondaires resolue angulairement." Toulouse 3, 1986. http://www.theses.fr/1986TOU30135.

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Influence de la topographie de surface induite par bombardement ionique sur l'emission electronique secondaire. Presentation des resultats et description de modeles rendant compte des principeles topographiques observees sur differentes cibles d'aluminium bombardees par des ions argon et xenon de 25 kev
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5

Attah, Isaac Kwame. "BINDING ENERGIES AND SOLVATION OF ORGANIC MOLECULAR IONS, REACTIONS OF TRANSITION METAL IONS WITH, AND PLASMA DISCHARGE IONIZATION OF MOLECULAR CLUSTERS." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/525.

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In this dissertation, different approaches have been employed to address the quest of understanding the formation and growth mechanisms of carbon-containing molecular ions with relevance to astrochemistry. Ion mobility mass spectrometry and DFT computations were used to investigate how a second nitrogen in the pyrimidine ring will affect the formation of a covalent bond between the benzene radical cation and the neutral pyrimidine molecule, after it was shown that a stable covalent adduct can be formed between benzene radical cation and the neutral pyridine. Evidence for the formation of a more stable covalent adduct between the benzene radical cation and the pyrimidine is reported here. The effect of substituents on substituted-benzene cations on their solvation by an HCN solvent was also investigated using ion mobility mass spectrometry and DFT computations were also investigated. We looked at the effect of the presence of electron-withdrawing substituents in fluorobenzene, 1,4 di- fluorobenzene, and benzonitrile on their solvation by up to four HCN ligands, and compared it to previous work done to determine the solvation chemistry of benzene and phenylacetylene by HCN. We report here the observed increase in the binding of the HCN molecule to the aromatic ring as the electronegativity of the substituent increased. We also show in this dissertation, DFT calculations that reveal the formation of both hydrogen-bonded and electrostatic isomers, of similar energies for each addition to the ions respectively. The catalytic activity of the 1st and 2nd row TM ions towards the polymerization of acetylene done using the reflectron time of flight mass spectrometry and DFT calculations is also reported in this dissertation. We explain the variation in the observed trend in C-H/C-C activity of these ions. We also report the formation of carbide complexes by Zr+, Nb+, and Mo+, with the acetylene ligands, and show the thermodynamic considerations that influence the formation of these dehydrogenated ion-ligand complexes. Finally, we show in this dissertation, a novel ionization technique that we employed to generate ions that could be relevant to the interstellar and circumstellar media using the reflectron time of flight mass spectrometry.
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6

Farrelly, Simone. "Therapeutic relationships in community mental health : the impact of the Joint Crisis Plan intervention." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/therapeutic-relationships-in-community-mental-health(522a86f6-0fbd-463a-8b4f-cb706078f541).html.

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Policy and professional guidance in England have emphasised the importance of Therapeutic Relationships (TRs) in community mental health care, yet there is no comprehensive model to guide practice or understand the process through which stronger TRs are generated. This thesis investigated TRs in community mental health for individuals with psychotic disorders and was embedded within the CRIMSON trial: a randomised controlled trial of the Joint Crisis Plan (JCP) intervention. JCPs contain service users’ treatment preferences for future care, which are jointly decided with clinicians. Qualitative analyses addressed participants’ views of TRs and JCPs. Quantitative analyses addressed the predictive utility of TRs for outcomes, associations of TRs and the effect of JCPs on service user and clinician-rated TR. Results suggested that significant ambiguity persists regarding what can and should be provided in community mental health, resulting in unhelpful experiences for service users and clinicians. A new model of TRs - Consistent Respect - was developed; it presents TRs as bi¬directional processes, jointly affected by clinicians’ and service users’ experiences of interactions and their roles defined by the wider context; the latter often being a barrier to the development of strong TRs. JCPs significantly improved service users’ appraisals of TRs by providing a structured protocol through which routine role enactments were limited and clinicians could demonstrate Consistent Respect. Positive effects were lost when there were deficiencies in the implementation of JCPs and/or engagement of clinicians. In conclusion, improving TRs through JCPs could facilitate better outcomes and more satisfactory treatment experiences for service users and clinicians. Changes in policy and practice are indicated to facilitate transparent goals and roles for clinicians and respectful interactions with service users.
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7

Ghosson, Hikmat. "Development of a novel universal proxy to assess the environmental fate and impact of complex (bio)pesticides by Mass Spectrometry-based Metabolomics." Electronic Thesis or Diss., Perpignan, 2020. http://www.theses.fr/2020PERP0029.

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Анотація:
Malgré la prise de conscience écologique et sanitaire, la consommation mondiale de pesticides est en augmentation. Étant donné que ces produits chimiques présentent de nombreux effets néfastes sur la santé humaine et l'environnement, des mesures doivent être prises afin de limiter leurs effets. Les produits de biocontrôle sont proposés comme une solution alternative aux produits synthétiques. En effet, ces « biopesticides » sont présumés être moins nocifs et relativement moins persistants. Toutefois, cet a priori doit être examiné et une évaluation stricte des risques de ces nouvelles substances doit être envisagée.Le développement de solutions de biocontrôle passe d'abord par les protocoles proposés pour étudier leur activité, leur devenir et leur impact environnemental. Actuellement, le temps de demi-vie (t½) est utilisé pour évaluer le devenir environnemental des pesticides synthétiques. Cependant, l'approche t½ ne donne que des informations sur la persistance des pesticides dans l'environnement, mais aucune indication concernant la formation de produits de dégradation ou son impact sur la biodiversité n'est apportée. De plus, les produits de biocontrôle sont des mélanges (bio)chimiques complexes. La t½ n'est pas applicable pour ces produits complexes. Par conséquent, de nouvelles approches analytiques doivent être envisagées afin de surmonter ces difficultés.Une nouvelle approche basée sur la méta-métabolomique et la Spectrométrie de Masse; « Empreinte Métabolique Environnementale » (EMF), a été récemment introduite. Elle offre un nouveau proxy universel et intégratif; le « temps de résilience », dédié à l'évaluation du devenir environnemental et de l'impact des (bio)pesticides complexes dans des matrices environnementales (ex. sol, sédiments). Néanmoins, le développement d'une telle approche de méta-métabolomique non ciblée basée sur la Spectrométrie de Masse doit être étudié en profondeur. Plusieurs tâches doivent alors être abordées: 1) les protocoles d'extraction performants et les méthodes analytiques basées sur la GC/LC-(HR)MS doivent être mis en place, 2) le traitement de données et les outils chimiométriques appropriés doivent être développés pour maitriser la complexité des ensembles des données générées, 3) l'impact de la complexité du xénométabolome sur les analyses basées sur la MS doit être évalué, et 4) l'étude des résidus volatiles doit être envisagée et nécessite donc le développement de nouvelles méthodologies analytiques.Le travail a été mené sur 3 axes principaux. Le premier axe portait sur 1) le développement de protocoles d'extraction et des méthodes LC-HRMS pour analyser à la fois les xénométabolites des pesticides et les endométabolites du sol, et 2) le développement d'une nouvelle approche chimiométrique pour évaluer les performances d'extraction. De nouveaux protocoles d'extraction se sont avérés optimaux pour l'EMF, et l'approche chimiométrique a donc été validée. Le deuxième axe a évalué l'impact de la complexité du xénométabolome sur la détermination des biomarqueurs environnementaux. La suppression d'ion a été révélée et une stratégie pragmatique a donc été élaborée pour surmonter son influence. Le troisième axe visait à mettre en place une nouvelle méthodologie pour analyser les résidus volatils de pesticides complexes. Des analyses HS-SPME-GC-MS ont été couplées à la chimiométrie afin de réaliser des études cinétiques et de suivre la transformation des résidus volatils. Le workflow chimiométrique a prouvé sa fiabilité pour expliquer la transformation du pesticide et de nouveaux xénométabolites et sous-produits ont été identifiés.En conclusion, une avancée significative a été apportée à l’EMF. Elle a été consolidée pour les applications en laboratoire et sur le terrain qui doivent être étudiées afin d'améliorer le proxy et de le valider comme une approche fiable pour l'évaluation des risques des pesticides
Despite the ecological and sanitary awareness, worldwide consumption of pesticides is increasing. As these chemical products represent several adverse effects on human health and environment, measures should be taken in order to limit their impacts. Biocontrol products are proposed as an alternative solution of the synthetic products. In fact, these “biopesticides” are presumed to be less harmful and relatively less persistent. However, this a priori must be examined and strict risk assessment of those new substances should be considered.The development of biocontrol solutions proceeds first of all through the proposed protocols to study their activity and their environmental fate and impact. Currently, half-life (DT50) is used in order to evaluate the environmental fate of synthetic pesticides. However, DT50 approach gives only information about pesticides' persistence in the environment, but no indications concerning the formation of degradation products or its impact on biodiversity are provided. Furthermore, biocontrol products are complex (bio)chemical mixes. The DT50 is not applicable for such complex products. Therefore, novel analytical approaches should be considered in order to overcome these difficulties.A novel approach based on meta-metabolomics and Mass Spectrometry; the “Environmental Metabolic Footprinting” (EMF), was recently introduced. It affords a novel universal and integrative proxy; the “resilience time”, dedicated to assess the environmental fate and impact of complex (bio)pesticides in environmental matrices (e.g. soil, sediment). Nonetheless, the development of such Mass Spectrometry-based untargeted meta-metabolomics approach needs to be in-depth studied. Several tasks should be addressed: 1) performant extraction protocols and GC/LC-(HR)MS-based analytical methods should be set up, 2) suitable data processing and chemometric tools should be developed to deal with the complexity of the generated datasets, 3) the impact of xenometabolome complexity on MS-based analyses should be assessed, and 4) the study of the volatile residues should be considered and thus needs new analytical methodologies to be developed.The work was carried out following 3 main axes. The first axis addressed 1) the development of extraction protocols and LC-HRMS methods to analyze both pesticides xenometabolites and soil endometabolites, and 2) the development of a novel chemometric approach to assess the extraction performance. Novel extraction protocols have been proven optimal for the EMF, and the chemometric approach was thus validated. The second axis assessed the impact of xenometabolome complexity on the determination of environmental biomarkers. Ion suppression was revealed and thus a pragmatic strategy has been developed to overcome its influence. The third axis aimed to set-up a novel methodology in order to analyze the volatile residues of complex pesticides. HS-SPME-GC-MS analyses were coupled to chemometrics in order to perform kinetics studies and to follow the transformation of the volatile residues. The chemometric workflow proved its reliability to explain pesticide’s transformation and novel xenometabolites and by-products were identified.In conclusion, significant advances were carried to the EMF. It has been consolidated for laboratory and field applications that must be investigated in order to improve the proxy and to validate it as a reliable approach for pesticides risk evaluation
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Tambosi, Reem. "Stress and toxicity of metal in photosynthetic bacteria : multi-scale study of the effects and the targets of metal ions and nanoparticles Silver and Copper Acute Effects on Membrane Proteins and Impact on Photosynthetic and Respiratory Complexes in Bacteria Silver Effect on Bacterial Cell Membrane Structure Investigated by Atomic Force and Scanning Electron Microscopes Cadmium and Copper Cross-tolerance. Cu+ alleviates Cd2+ toxicity, and both cations target heme and chlorophyll biosynthesis pathway in Rubrivivax gelatinosus Additive effects of metal excess and superoxide, a highly toxic mixture in bacteria." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL070.

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L’usage intensif des métaux et des ions métalliques dans l'industrie et l'agriculture représente une menace sérieuse pour l'environnement et pour tous les êtres vivants en raison de la toxicité aiguë de ces ions. Cependant, cela peut aussi être un outil prometteur. En effet, les ions comme les nanoparticules d'argent sont très utilisés dans diverses applications médicales, industrielles et sanitaires. L'effet antimicrobien de ces nanoparticules est en partie lié aux ions Ag⁺ libérés et à leur capacité à interagir avec les membranes bactériennes. L'objectif de ce projet est d'étudier l'interaction entre un objet biologique (les bactéries) et des objets physiques (métaux), pour comprendre l'impact des métaux sous différentes formes (ions, nanoparticules et nanostructures) sur les cellules bactériennes en utilisant différentes approches: de physiologie, biochimie, génétique et de biologie cellulaire. Nous avons utilisé comme modèles biologiques, principalement la bactérie photosynthétique pourpre Rubrivivax (R.) gelatinosus, mais aussi Escherichia coli; et pour les objets physiques, nous avons utilisé l'argent comme métal principal mais aussi d'autres métaux (cuivre, cadmium et nickel) à titre de comparaison. Les principaux objectifs de ce travail sont: 1- d'étudier l'impact et les mécanismes de toxicité de ces ions métalliques / NPs sur les métabolismes bactériens respiratoire et photosynthétique. 2- Identifier des gènes bactériens impliqués dans la réponse à un excès d'ions Ag⁺. 3- Etudier l'internalisation et l'interaction des ions métalliques et des NP au sein des membranes biologiques. Ainsi, nous avons pu identifier, à la fois in vitro et in vivo, des cibles spécifiques d'ions Ag⁺ et Cu²⁺ dans la membrane des bactéries. Cela inclut des complexes impliqués dans la photosynthèse, mais également des complexes de la chaine respiratoire. Il a été démontré que les ions Ag⁺ et Cu²⁺ ciblent spécifiquement une bactériochlorophylle exposée au solvant dans les antennes de collecte de lumière du photosystème de la bactérie. Ceci présente également, à notre connaissance, la première preuve directe de dommages induits par des ions Ag⁺ sur les protéines membranaires impliquées dans ces métabolismes. Par ailleurs, nous avons également réalisé une étude comparative par microscopie (AFM/ MEB) de l'effet de l'Ag⁺ en solution ou des Ag-NPs synthétisés dans notre laboratoire, sur la morphologie des cellules bactériennes
The extensive use of metal ions in industry and agriculture represents a serious threat to the environment and to all living being because of the acute toxicity of these ions. However, it can also be a promising tool, silver ions and nanoparticles are some of the most widely used metals in various industrial and health applications. The antimicrobial effect of these nanoparticles is in part related to the released Ag⁺ ions and their ability to interact with bacterial membranes. The goal of this project is to study the interaction between biological subject (the bacteria) and physical objects (metals), and more specifically to understand the impact of metals in different forms (ions, nanoparticles and nanostructures) on the growth of the bacterial cells using different approaches : physiology, biochemistry, genetics and cell biology. We used as biological models, principally the purple photosynthetic bacterium Rubrivivax (R.) gelatinosus, but also Escherichia coli; and for physical objects, we used silver as main metal but also other metals (copper, cadmium and nickel) for comparison. The main objectives are: 1- to study the impact and the mechanisms of toxicity of these metallic ions/NPs on the bacterial respiratory and photosynthesis metabolisms. 2- To identify the bacterial genes involved in response to excess silver. 3- To study the internalization and interaction of metals ions and NPs within biological membranes. The results showed that we were able to identify, both in vitro and in vivo, specific targets of Ag⁺ and Cu²⁺ ions within the membrane of bacteria. This include complexes involved in photosynthesis, but also complexes involved in respiration. Ag⁺ and Cu²⁺ were shown to specificaly target a solvent exposed bacteriochlorophyll in the light harvesting antennae of the photosystem. This also presents, in our knowledge, the first direct evidence of silver ions damages to membrane proteins involved in these metabolisms. We also carried out a microscopy (AFM/ SEM) comparative study of the effect of Ag⁺ ions or Ag-NPs synthesized in our laboratory, on the bacterial cell morphology
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Hopkin, Gareth Daniel. "The impact of the critical time intervention for people with severe mental illness in the transition from prison to the community." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/the-impact-of-the-critical-time-intervention-for-people-with-severe-mental-illness-in-the-transition-from-prison-to-the-community(8855e2e2-276c-4fe4-b8b5-a49c9fe0fbb3).html.

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Background: There are high rates of mental health problems among prisoners and the prevalence of severe mental illness is far higher than in the community. Although mental health services have become well established within prisons in England and Wales, the transition from prison to the community presents difficulties for the provision of care and there are negative outcomes during this period. Methods: Participants were recruited from eight prisons in London and the North West of England and randomised to receive either the Critical Time Intervention or treatment as usual. They were followed up at six weeks, six months and 12 months and a number of variables were measured at each time point. A sub sample of these participants and members of prison and community staff also completed qualitative interviews. Results: One hundred and fifty participants were recruited and follow up data were collected for 116 participants at six week follow up and 98 and 85 participants at six months and at 12 months. Participants in the CTI group had significantly higher levels of contact with; (I) any mental health professional, (II) allocation of a care co-ordinator and; (III) contact with a care co-ordinator compared to the TAU group. These differences were not significant at six month or at 12 month follow up. Legal status and problem drug use were associated with better outcomes at six weeks after release from prison and GP involvement in care on entry was associated with worse outcomes. Themes relating to needs and problems after release, the perceived benefits and problems of the Critical Time Intervention, and provision of care in this period were identified in qualitative interviews. Conclusions: The Critical Time Intervention is effective in improving outcomes in the early transition from prison to the community and should be considered by decision makers at the national or regional level. Further research should determine whether the CTI is effective as a service and whether it has a beneficial effect on other important outcomes.
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Pederick, Victoria Grace. "Characterisation of the ATP-binding cassette transporters of Pseudomonas aeruginosa." Thesis, 2015. http://hdl.handle.net/2440/106301.

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Pseudomonas aeruginosa is a ubiquitous, Gram-negative, rod-shaped, environmental bacterium. However, it is also a clinically significant, opportunistic human pathogen, responsible for life-threatening infections in immunocompromised persons, including those with cancer and significant burn wounds. Furthermore, P. aeruginosa infections are the primary cause of morbidity and mortality in individuals with the genetic disease cystic fibrosis. The success of P. aeruginosa as both an environmental organism and a human pathogen can be attributed to its 6.3 Mbp genome, which encodes an array of mechanisms that enable adaptation, persistence and propagation in diverse environments. Membrane transporters are critical to the ability of P. aeruginosa to adapt and respond to its environment. Of these proteins, the ATP-binding cassette (ABC) transporters hold a prominent role in cellular processes, facilitating the active translocation of molecules across the inner membrane. The conserved structural organisation of ABC transporters has enabled their classification based upon the vector of transport, as either efflux or import transporters. Bioinformatic analyses reveal that P. aeruginosa PAO1 is predicted to encode 289 proteins associated with ABC transporter functionality, with a subset shown to contribute to in vivo virulence. This study presents the phenotypic characterisation of five putative ABC export proteins in P. aeruginosa PAO1, assessing their contribution to antibiotic efflux. Deletion mutants of each identified ABC exporter were assessed for changes in their antibiotic resistance profile. Transcriptional analysis of the ABC transporter genes in response to antibiotic treatment was also performed to detect drug-stimulated expression. These analyses revealed the PA0860, PA1113, PA1876, PA3228 and PA5231 ABC efflux proteins to have a negligible contribution to antibiotic resistance, with bioinformatic analyses subsequently utilized to propose alternative roles. ABC importers, also known as ABC permeases, typically feature one, but sometimes multiple, solute-binding protein (SBP) component(s) that deliver the cargo molecule to the ABC transporter for cytoplasmic translocation. ABC permeases are central to the uptake of many essential nutrients in prokaryotes, including transition metal ions. Herein, this study characterises the acquisition and role of two crucial transition metal ions, molybdenum and zinc, in P. aeruginosa. Acquisition of either metal ion was shown to occur primarily via ABC permeases, molybdenum via ModABC, and zinc via ZnuABC. Deletion of the modA SBP gene abrogated molybdenum accumulation in P. aeruginosa and abolished the capacity for anaerobic growth or nitrate reduction. Unexpectedly, conditions that permitted nitrate reduction were shown to inhibit biofilm formation and alter membrane fatty acid composition. By contrast, although deletion of the zinc-specific SBP gene, znuA, reduced cellular zinc accumulation, the mutant strain did not exhibit a phenotype corresponding with zinc depletion. Transcriptional analyses revealed that P. aeruginosa encodes a number of additional, previously unidentified, putative mechanisms that enable it to adapt to cellular zinc deficiency, including the use of several uncharacterized zinc acquisition systems. Collectively, this study represents a significant advance in our understanding of P. aeruginosa ABC transporters and offers detailed insight into their cellular functions. Furthermore, this work highlights the remarkable adaptability of the bacterium, which enables its survival in diverse environmental and host niches.
Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2015.
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Книги з теми "Metal ion import"

1

Noakes, Timothy Charles Quentin. Coaxial impact collision ion scattering spectroscopy of semiconductor and metal surfaces. [s.l.]: typescript, 1995.

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Ozberk, Engin. Impact of iron control on process selection. [Montreal?]: SNC, 1986.

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Peter, Farrell, and National EDY Users' Conference (2nd : 1983 : Manchester, England), eds. EDY, its impact on staff training in mental handicap. Manchester, UK: Manchester University Press, 1985.

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4

The impact of early life trauma on health and disease: The hidden epidemic. Cambridge, UK: Cambridge University Press, 2010.

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5

Group for the Advancement of Psychiatry. Committee on Adolescence., ed. Crises of adolescence, teenage pregnancy: Impact on adolescent development. New York: Brunner/Mazel, 1986.

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6

New Jersey. Legislature. General Assembly. Regulatory Oversight Committee. Committee meeting of Assembly Regulatory Oversight Committee: Assembly bill no. 2355 (requires impact statement for any proposed regulation affecting volunteer ambulance squad and fire company) ; Testimony on the status of removing adjudicated juveniles with mental illness from the juvenile correctional facilities to provide them with mental health treatment : [January 13, 2005, Trenton, New Jersey]. Trenton, N.J: The Unit, 2005.

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Addison, Tony, and Atanu Ghoshray. Pandemics and their impact on oil and metal prices. UNU-WIDER, 2020. http://dx.doi.org/10.35188/unu-wider/2020/914-3.

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We examine the effect of pandemics on selected commodity prices—in particular, those of zinc, copper, lead, and oil. We set up a vector autoregressive model and analyse data since the mid-nineteenth century to determine how prices reacted to pandemics such as the 1918 Spanish Flu, 1957 Asian Flu, and 1968 Hong Kong Flu. We control for demand and supply fundamentals to generate forecasts from the point of outbreak, and we consider whether any pattern can be deduced in reactions to adverse global shocks. Results are varied, depending on choice of commodity and magnitude and type of response. No clear conclusions are possible from past pandemics, and we conclude that at the time of writing, forecasts are difficult to make in the ongoing current pandemic too. We conclude by estimating impulse response functions to assess likely impact and the subsequent response of commodity prices to the shock.
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(Editor), Astrid Sigel, Helmut Sigel (Editor), and Roland K. O. Sigel (Editor), eds. Nickel and Its Surprising Impact in Nature: Metal Ions in Life Sciences. Wiley, 2007.

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Sigel, Helmut, Astrid Sigel, and Sigelroland K. O. Nickel And Its Surprising Impact in Nature: Metal Ions in Life Sciences. John Wiley & Sons Inc, 2006.

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Muhly, James D. Metals and Metallurgy. Edited by Gregory McMahon and Sharon Steadman. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780195376142.013.0039.

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This article reviews the impact of metals and metallurgy on Anatolian societies, from the first emergence of metal experimentation in the Neolithic to the full-blown metallurgical societies of the Bronze Age. Evidence suggests that Late Chalcolithic metalworkers thought of tin as a metal to be used for coating the surface of a copper artifact, presumably to imitate the appearance of silver, before they thought of adding tin to molten copper to produce bronze. During the transition from Late Chalcolithic to the beginning of the Early Bronze Age, ca. 3000 BCE, the main focus of metallurgical development in Anatolia shifted from the eastern part of the country to central and western Anatolia.
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Частини книг з теми "Metal ion import"

1

Walz, Wolfgang. "The Impact of Extracellular Potassium Accumulation in Stroke." In Metal Ion in Stroke, 363–72. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4419-9663-3_17.

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Glasius, Marlies, Meta de Lange, Jos Bartman, Emanuela Dalmasso, Aofei Lv, Adele Del Sordi, Marcus Michaelsen, and Kris Ruijgrok. "Mental Impact." In Research, Ethics and Risk in the Authoritarian Field, 77–95. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-68966-1_5.

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Brown, Donald H., and W. Ewan Smith. "The impact of metal ion chemistry on our understanding of enzymes." In Enzyme Chemistry, 227–64. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1832-0_6.

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Cellier, Mathieu F. M. "Nutritional Immunity: Homology Modeling of Nramp Metal Import." In Advances in Experimental Medicine and Biology, 335–51. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-0106-3_19.

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Prasad, M. N. V., and K. Strzałka. "Impact of Heavy Metals on Photosynthesis." In Heavy Metal Stress in Plants, 117–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-662-07745-0_6.

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Keune, Katrien, Rick P. Kramer, Suzanne Stangier, and Margriet H. van Eikema Hommes. "Impact of Lead Soaps on the Formation of Age Craquelure." In Metal Soaps in Art, 107–21. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-90617-1_6.

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Mishra, Preeti, Afifa Qidwai, Nivedita Singh, Anupam Dikshit, and S. C. Agrawal. "Heavy Metal Toxicity in Plants: Impact, Signaling, and Remediation Strategies." In Heavy Metal Toxicity in Plants, 11–26. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003155089-2.

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Kempter, V., and M. Brause. "Metals on Metal Oxides: Study of Adsorption Mechanisms with the Metastable Impact Electron Spectroscopy (MIES)." In Defects and Surface-Induced Effects in Advanced Perovskites, 249–59. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4030-0_24.

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Matthäus, R., R. Moshammer, and K. Wien. "Energy and Angular Distributions of Secondary Ions Ejected from Clean Metals by MeV Ion Impact." In NATO ASI Series, 55–59. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4684-7926-3_7.

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Duhm, Steffen, Christoph Bürker, Takuya Hosokai, and Alexander Gerlach. "Vertical Bonding Distances Impact Organic-Metal Interface Energetics." In Electronic Processes in Organic Electronics, 89–107. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-55206-2_6.

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Тези доповідей конференцій з теми "Metal ion import"

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SKACHKOV, Viktor, Olga BEREZHNA, Vira ANISHCHENKO, and Ruslan GNATYSHAK. "IMPACT OF OXIDATION PROCESSES IN AN OXYGEN ION ENVIRONMENT ON THE PROPERTIES OF MOULDINGS FROM ALUMINUM POWDERS." In METAL 2021. TANGER Ltd., 2021. http://dx.doi.org/10.37904/metal.2021.4236.

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Zhao, Chen, Guowei Zhong, Da-Eun Kim, Jinxia Liu, and Xinyu Liu. "A Portable Analytical System for Colorimetric Detection of Metal Ions in Water." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38994.

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Heavy metal ions released into various water environments have severe impact on both human beings and aqueous environments, and excess amount of lead and aluminum ions pose high risks to human health and could cause life-threatened diseases. The existence of metal ions in drinking water contributes most to the daily intake by humans, and thus it urges to develop a rapid, low-cost and sensitive method for detection of heavy metal ions. In this research, we develop a portable analytical system for metal ion detection in water by combining a powerful gold nanoparticle (AuNP) based colorimetric method with lab-on-a-chip technology. We utilize single-step assays involving surface functionalized AuNPs for colorimetric detection of lead (Pb2+) and aluminum (Al3+) ions in water with low limit of detection (LOD) and high sensitivity. We demonstrate that this portable system provides LODs of 30 ppb for Pb2+ and 89 ppb for Al3+, both comparable to bench-top analytical spectrometers. The system permits metal ion detections in a more economical and convenient fashion, and is particularly useful for water quality monitoring in remote and/or resource-poor settings.
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Ryabchikov, A. I., D. O. Sivin, and S. V. Dektyarev. "High-intensity ion beams with submillisecond duration for synergistic of ion implantation and energy impact on the surface." In 8th International Congress on Energy Fluxes and Radiation Effects. Crossref, 2022. http://dx.doi.org/10.56761/efre2022.c1-p-018301.

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The development of methods to modify materials based on the synergistic high-intensity implantation and simultaneous energy impact on the ion-doped layer involves using the pulsed and repetitively-pulsed beams of metal and gas ion beams with micro-submillisecond duration with high pulsed power density. The paper presents the results of experimental studies on the formation of pulsed and repetitively-pulsed high-intensity beams of titanium ions with a pulse duration from 150 to 500 μs. The plasma flow was generated by a vacuum arc discharge. To obtain ion beams with a power density in the range from several tens to several hundreds of kilowatts per square centimeter, ballistic focusing of ions was used using an extracting grid electrode in the form of a part of a sphere. The features of the forming the high-power repetitively-pulsed beams of titanium ions were studied using both the ion source “Rainbow 5”. Data are presented on the influence of the ion beam space charge neutralization processes at current densities from fractions to several amperes per square centimeter on the efficiency of the ion beam’s transport and focusing at accelerating voltages from 10 to 30 kV.
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Weiland, Lisa Mauck, and Donald J. Leo. "Computational Micromechanics Analysis of Ionic Polymers With Cluster Morphology." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-61878.

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In recent years there has been considerable study of the potential mechanisms underlying the electro-mechanical response of ionic-polymer-metal composites (IPMCs). Most of these efforts have employed assumptions of uniform and balanced ion distribution within spherical cluster shapes, in the ionic polymer layer of the IPMC. Inspired by the results of a preliminary computational study, the present work investigates the impact of dispensing with these assumptions. A computational micromechanics model has been developed to study ion response in a single cluster of these ionomeric transducers. Assuming a constant solvated state, the model tracks the position of individual ions within a given cluster in response to ion-ion interaction, mechanical stiffness of the pendant chain, cluster surface response force, and external electric field loading. Results suggest that the classic assumptions will tend to under-predict electromechanical response and that charge imbalance has significant impact of cluster behavior.
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Banerjee, Soumik, Sohail Murad, and Ishwar K. Puri. "Carbon Nanotubes as Nano-Pumps: A Molecular Dynamics Investigation." In ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2006. http://dx.doi.org/10.1115/icnmm2006-96206.

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This paper focuses on the use of carbon nanotubes (CNT) for ion separation and encapsulation from a solution containing both positive and negatively charged ions. Metal ion separation from drinking water or during material processing applications can be an important issue. We use molecular dynamics simulations to demonstrate that a pair of carbon nanotubes with patterned positive and negative charges can form the basis of an effective device for the separation or encapsulation of ions. We consider three different charge patterns: i) Electrodes, where all the atoms of a CNT are charged with a finite surface charge density; ii) Alternate axial bands of positive and negative charges on each electrode; and iii) Alternate circumferential rings of positive and negative charges on the electrodes. The charge pattern determines the preferential intake of water and/or ions by a nanotube. As conventional electrodes they adsorb ions, but with an alternate band or ring charge pattern they adsorb the water molecules. Our simulations show that a charged CNT can be used as a nano-pump that provides purified water or ions from an impure solution.
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Darwish, M., Dipanjan Saha, J. Malen, and J. A. Weldon. "A comparison of the impact of metal-ion containing and metal-ion free photoresist developers on graphene field-effect transistors." In 2017 IEEE 17th International Conference on Nanotechnology (IEEE-NANO). IEEE, 2017. http://dx.doi.org/10.1109/nano.2017.8117350.

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Mamaev, A. V., D. D. Hrynshpan, N. G. Tsygankova, and T. A. Savitskaya. "OBTAINING HIGHLY ACTIVE MESOPOROUS COAL FROM WASTE OF THE WOOD PROCESSING INDUSTRY." In SAKHAROV READINGS 2022: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2022. http://dx.doi.org/10.46646/sakh-2022-2-304-307.

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A method for producing of mesoporous activated carbon with a high specific surface area equal to 1289 m2/g is considered. The resulting coal has a very high sorption capacity for methylene blue, equal to 610 mg/g, and also exhibits ion-exchange properties with respect to heavy metal ions. Coal obtained in this method, in terms of its performance, significantly exceeds the best world analogues, but its cost is 4 times lower than the cost of imported activated carbon. Due to the presence of mesopores, activated carbon has a wide range of applications, and its production in Belarus will be profitable and help reduce the amount of wood waste generated.
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Sapir, Zvika, Oksana Dimnich, and Avraham Raz. "Impact of PFIB Gas Assisted Delayering on MOSFET Degradation." In ISTFA 2022. ASM International, 2022. http://dx.doi.org/10.31399/asm.cp.istfa2022p0284.

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Abstract Delayering is an essential sample preparation step in physical failure analysis (PFA) of integrated circuits (IC). During delayering it is crucial to precisely control the endpoint and uniformity of the region of interest (ROI). Furthermore, to perform SEM based nanoprobing it is also required to end the delayering process without residues on the surface that will reduce conductivity of, or induce shorts between, isolated contacts. Delayering via mechanical polishing has been the main approach for PFA and nanoprobing. However, as the shrinkage of the interconnect layer thickness reduced below 100 nm, it has become very challenging to control the polish endpoint and to achieve robustly controlled process. Recently gas assisted Xe+ Plasma FIB (PFIB) has demonstrated uniform delayering of the metal and dielectric layers, achieving a planar surface of heterogeneous materials. The purpose of this study is to analyze the PFIB ion beam interaction with MOSFET devices, addressing ion beam damage related device degradation. We explored the final surface treatment required for nanoprobing and the impact on MOSFETs. For this purpose, we monitored device parameters after PFIB delayering final steps with different beam conditions and compare PFIB prepared samples to polished prepared samples. Consequently, we summarize the considerations of parameters for ion beam on final surface treatment.
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Zimovets, Alina, Alina Zimovets, Yury Fedorov, Yury Fedorov, Asya Ovsepyan, Asya Ovsepyan, Vyacheslav Savitskiy, and Vyacheslav Savitskiy. "THE REGULARITY OF HEAVY METALS DISTRIBUTION AND BEHAVIOR IN THE BOTTOM SEDIMENTS ON THE PROFILE “NORTHERN DVINA RIVER – WHITE SEA”." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.31519/conferencearticle_5b1b93c8b57a02.64869435.

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A study was conducted to investigate the level of heavy metals in bottom sediments of the Northern Dvina mouth area and the White Sea in various seasons since 2004. Of greatest interest for the study was presented as such heavy metals as Hg, Pb, Cd, Cu, Ni, Zn, Cr, which belong to the priority group of toxic elements. The heavy metals concentrations were determined with atomic absorption spectrometer. Also the grain-size composition, concentrations of organic carbon and values of hydrogen ion exponent (pH) and redox potential (Eh) in bottom sediments were determined. It was found that the levels of heavy metals in sediments significantly changed in the lateral radial direction. There is a tendency to increased concentrations of some heavy metals downstream of the river. The high concentrations of heavy metals were found within the influence of cities and towns. So the extremely high mercury concentrations were found in the sediments of small and shallow channels crossing the Arkhangelsk city. The study of heavy metal concentrations in the bottom sediments along the profile “the Northern Dvina - Dvina Bay - White sea” showed that the marginal filter contributes to the coprecipitation with suspended metals of anthropogenic genesis. These processes greatly reduce the contamination risk of the White Sea. Thus, the impact of the river on the ecosystem of the White Sea outside the marginal filter is significantly less.
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Zimovets, Alina, Alina Zimovets, Yury Fedorov, Yury Fedorov, Asya Ovsepyan, Asya Ovsepyan, Vyacheslav Savitskiy, and Vyacheslav Savitskiy. "THE REGULARITY OF HEAVY METALS DISTRIBUTION AND BEHAVIOR IN THE BOTTOM SEDIMENTS ON THE PROFILE “NORTHERN DVINA RIVER – WHITE SEA”." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.21610/conferencearticle_58b431771359a.

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A study was conducted to investigate the level of heavy metals in bottom sediments of the Northern Dvina mouth area and the White Sea in various seasons since 2004. Of greatest interest for the study was presented as such heavy metals as Hg, Pb, Cd, Cu, Ni, Zn, Cr, which belong to the priority group of toxic elements. The heavy metals concentrations were determined with atomic absorption spectrometer. Also the grain-size composition, concentrations of organic carbon and values of hydrogen ion exponent (pH) and redox potential (Eh) in bottom sediments were determined. It was found that the levels of heavy metals in sediments significantly changed in the lateral radial direction. There is a tendency to increased concentrations of some heavy metals downstream of the river. The high concentrations of heavy metals were found within the influence of cities and towns. So the extremely high mercury concentrations were found in the sediments of small and shallow channels crossing the Arkhangelsk city. The study of heavy metal concentrations in the bottom sediments along the profile “the Northern Dvina - Dvina Bay - White sea” showed that the marginal filter contributes to the coprecipitation with suspended metals of anthropogenic genesis. These processes greatly reduce the contamination risk of the White Sea. Thus, the impact of the river on the ecosystem of the White Sea outside the marginal filter is significantly less.
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Звіти організацій з теми "Metal ion import"

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Clausen, Jay, Samuel Beal, Thomas Georgian, Kevin Gardner, Thomas Douglas, and Ashley Mossell. Effects of milling on the metals analysis of soil samples containing metallic residues. Engineer Research and Development Center (U.S.), July 2021. http://dx.doi.org/10.21079/11681/41241.

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Metallic residues are distributed heterogeneously onto small-arms range soils from projectile fragmentation upon impact with a target or berm backstop. Incremental Sampling Methodology (ISM) can address the spatially heterogeneous contamination of surface soils on small-arms ranges, but representative kilogram-sized ISM subsamples are affected by the range of metallic residue particle sizes in the sample. This study compares the precision and concentrations of metals in a small-arms range soil sample processed by a puck mill, ring and puck mill, ball mill, and mortar and pestle prior to analysis. The ball mill, puck mill, and puck and ring mill produced acceptable relative standard deviations of less than 15% for the anthropogenic metals of interest (Lead (Pb), Antimony (Sb), Copper (Cu), and Zinc (Zn)), with the ball mill exhibiting the greatest precision for Pb, Cu, and Zn. Precision by mortar and pestle, without milling, was considerably higher (40% to >100%) for anthropogenic metals. Media anthropogenic metal concentrations varied by more than 40% between milling methods, with the greatest concentrations produced by the puck mill, followed by the puck and ring mill and then the ball mill. Metal concentrations were also dependent on milling time, with concentrations stabilizing for the puck mill by 300 s but still increasing for the ball mill over 20 h. Differences in metal concentrations were not directly related to the surface area of the milled sample. Overall, the tested milling methods were successful in producing reproducible data for soils containing metallic residues. However, the effects of milling type and time on concentrations require consideration in environmental investigations.
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Olson, L. Impact of ZR content on radionuclide release rates in metal waste forms. Office of Scientific and Technical Information (OSTI), September 2015. http://dx.doi.org/10.2172/1215489.

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Barker, Amanda, Jay Clausen, Thomas Douglas, Anthony Bednar, Christopher Griggs, and William Martin. Environmental impact of metals resulting from military training activities : a review. Engineer Research and Development Center (U.S.), February 2022. http://dx.doi.org/10.21079/11681/43348.

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The deposition of metals into the environment as a result of military training activities remains a longterm concern for Defense organizations across the globe. Of particular concern for deposition and potential mobilization are antimony (Sb), arsenic (As), copper (Cu), lead (Pb), and tungsten (W), which are the focus of this review article. The fate, transport, and mobilization of these metals are complicated and depend on a variety of environmental factors that are often convoluted, heterogeneous, and site dependent. While there have been many studies investigating contaminant mobilization on military training lands there exists a lack of cohesiveness surrounding the current state of knowledge for these five metals. The focus of this review article is to compile the current knowledge of the fate, transport, and ultimate risks presented by metals associated with different military training activities particularly as a result of small arms training activities, artillery/mortar ranges, battleruns, rocket ranges, and grenade courts. From there, we discuss emerging research results and finish with suggestions of where future research efforts and training range designs could be focused toward further reducing the deposition, limiting the migration, and decreasing risks presented by metals in the environment. Additionally, information presented here may offer insights into Sb, As, Cu, Pb, and W in other environmental settings.
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Pindzola, M. S., D. C. Griffin, C. Bottcher, D. C. Gregory, A. M. Howald, R. A. Phaneuf, D. H. Crandall, G. H. Dunn, D. W. Mueller, and T. J. Morgan. Survey of experimental and theoretical electron-impact ionization cross sections for transition metal ions in low stages of ionization. Office of Scientific and Technical Information (OSTI), March 1985. http://dx.doi.org/10.2172/6089462.

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Burgos, W. D. Impact of Iron-Reducing Bacteria on Metals and Radionuclides Adsorbed to Humic-Coated Iron(III) Oxides. Office of Scientific and Technical Information (OSTI), February 2005. http://dx.doi.org/10.2172/876706.

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Heyns,, Christof, Rachel Jewkes,, Sandra Liebenberg,, and Christopher Mbazira,. The Hidden Crisis: Mental Health on Times of Covid-19. Academy of Science of South Africa (ASSAf), 2021. http://dx.doi.org/10.17159/assaf.2019/0066.

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[This Report links with the video "The policy & practice of drug, alcohol & tobacco use during Covid-19" http://hdl.handle.net/20.500.11911/171 ]. The COVID-19 pandemic is most notably a physical health crisis, but it strongly affects mental health as well. Social isolation, job and financial losses, uncertainty about the real impact of the crisis, and fear for physical well-being affect the mental health of many people worldwide. These stressors can increase emotional distress and lead to depression and anxiety disorders. At the same time, there are enormous challenges on the health care side. People in need of mental health support have been increasingly confronted with limitations and interruptions of mental health services in many countries. In May 2020, the United Nations already warned that the COVID-19 pandemic has the seeds of a major mental health crisis if action is not taken. The panel discussed and analysed mental health in times of the COVID-19 pandemic with reference to South Africa, Nigeria, Germany and Spain.
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Xourafi, Lydia, Polyxeni Sardi, and Anastasia Kostaki. Exploring psychological vulnerability and responses to the COVID-19 lockdown in Greece. Verlag der Österreichischen Akademie der Wissenschaften, July 2022. http://dx.doi.org/10.1553/populationyearbook2022.dat.5.

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This study explores the psychosocial impact of the COVID-19 pandemic on the population in Greece during the general lockdown period. Specifically, depression, anxiety and stress scores, as well as the factors associated with vulnerability to developing mental health conditions during this period, were investigated. A total of 911 adults participated in an online survey by completing a self-reporting questionnaire that included demographic questions, DASS-42 items (anxiety, stress and depression scales) and other questions related to personal experience. Regression modelling uncovered a significant relationship between gender and DASS scores, with women having significantly higher scores than men for all mental health problems. Participants aged 20–39 years were especially vulnerable to experiencing poor mental health. Unemployed participants reported having worse mental health than others. Having more perceived psychosocial support during the pandemic was associated with lower overall scores. Thus, women, young adults and the unemployed exhibited particularly high levels of vulnerability, while individuals who received social support from relatives and friends during the lockdown were more resilient to the effects of social isolation.
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Hikaru Hiruta and Gilles Youinou. Impact of Fission Products Impurity on the Plutonium Content of Metal- and Oxide- Fuels in Sodium Cooled Fast Reactors. Office of Scientific and Technical Information (OSTI), September 2013. http://dx.doi.org/10.2172/1111507.

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Ji, Yi, Bob McCullouch, and Zhi Zhou. Evaluation of Anti-Icing/De-Icing Products Under Controlled Environmental Conditions. Purdue University, 2020. http://dx.doi.org/10.5703/1288284317253.

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Snow and ice removal are important tasks during the winter season and large amounts of anti-icing and de-icing chemicals are used and there is a critical need to review and synthesize information from the literature to compare and contrast anti-icing and de-icing chemicals to understand their environmental impact and support decision making. The effectiveness, costs, and environmental impact of commonly used and alternative anti-icing and de-icing chemicals were reviewed in this study. Application of anti-icing and de-icing chemicals may increase ion concentrations in soils and change nitrogen cycle, soil pH, and trace metal concentrations, affect surface water and groundwater, and increase public health risks. Life cycle assessment was conducted to quantitively evaluate environmental impact of selected anti-icing and de-icing chemicals. A decision support tool on environmental impact was developed to evaluate environmental impact of anti-icing and de-icing chemicals in ten different environmental impact categories. The results showed the environmental life cycle assessment tool developed in this study can be used to compare multiple environment impacts to support decision making for winter operation chemicals.
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Williamson, M. C., R. J. McNeil, S. J. A. Day, M. W. McCurdy, R. H. Rainbird, and E. C. Grunsky. Environmental impact of gossans revealed by orientation surveys for base metals in the Canadian Arctic Islands. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2015. http://dx.doi.org/10.4095/296583.

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