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Sample records for manganese define multiple

  1. Manganese

    International Nuclear Information System (INIS)

    Fayziev, A.R.

    2002-01-01

    Present article is devoted to manganese content in fluoride. The manganese content of some geologic deposits of Tajikistan was determined by means of chemical analysis. The mono mineral samples of fluorite of 5 geologic deposits of various mineralogical and genetic type was studied. The manganese content in fluorite of geologic deposits of various mineralogical and genetic type was defined.

  2. Defining active progressive multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, Finn; Börnsen, Lars; Ammitzbøll, Cecilie

    2017-01-01

    BACKGROUND: It is unknown whether disease activity according to consensus criteria (magnetic resonance imaging activity or clinical relapses) associate with cerebrospinal fluid (CSF) changes in progressive multiple sclerosis (MS). OBJECTIVE: To compare CSF biomarkers in active and inactive...

  3. Sporulation of Clostridium cylindrosporum on a Defined, Low-Manganese Medium

    OpenAIRE

    Sacks, L. E.; Smith, M. R.

    1987-01-01

    Clostridium cylindrosporum HC-1 grew and sporulated well on a defined medium. This is the first demonstration of sporulation of a purinolytic clostridium on a defined medium; manganese levels were below those considered essential for sporulation of most Bacillus species. Sporulation appeared to be initiated before exhaustion of the purine substrate.

  4. Manganese

    Science.gov (United States)

    ... research suggests that taking a specific product (7-Keto Naturalean) containing manganese, 7-oxo-DHEA, L-tyrosine, ... can absorb.Milk proteinAdding milk protein to the diet might increase the amount of manganese the body ...

  5. Manganese

    Science.gov (United States)

    Cannon, William F.; Kimball, Bryn E.; Corathers, Lisa A.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Manganese is an essential element for modern industrial societies. Its principal use is in steelmaking, where it serves as a purifying agent in iron-ore refining and as an alloy that converts iron into steel. Although the amount of manganese consumed to make a ton of steel is small, ranging from 6 to 9 kilograms, it is an irreplaceable component in the production of this fundamental material. The United States has been totally reliant on imports of manganese for many decades and will continue to be so for at least the near future. There are no domestic reserves, and although some large low-grade resources are known, they are far inferior to manganese ores readily available on the international market. World reserves of manganese are about 630 million metric tons, and annual global consumption is about 16 million metric tons. Current reserves are adequate to meet global demand for several decades. Global resources in traditional land-based deposits, including both reserves and rocks sufficiently enriched in manganese to be ores in the future, are much larger, at about 17 billion metric tons. Manganese resources in seabed deposits of ferromanganese nodules and crusts are larger than those on land and have not been fully quantified. No production from seabed deposits has yet been done, but current research and development activities are substantial and may bring parts of these seabed resources into production in the future. The advent of economically successful seabed mining could substantially alter the current scenario of manganese supply by providing a large new source of manganese in addition to traditional land-based deposits.From a purely geologic perspective, there is no global shortage of proven ores and potential new ores that could be developed from the vast tonnage of identified resources. Reserves and resources are very unevenly distributed, however. The Kalahari manganese district in South Africa contains 70 percent of the world’s identified resources

  6. Defining Multiple Chronic Conditions for Quality Measurement.

    Science.gov (United States)

    Drye, Elizabeth E; Altaf, Faseeha K; Lipska, Kasia J; Spatz, Erica S; Montague, Julia A; Bao, Haikun; Parzynski, Craig S; Ross, Joseph S; Bernheim, Susannah M; Krumholz, Harlan M; Lin, Zhenqiu

    2018-02-01

    Patients with multiple chronic conditions (MCCs) are a critical but undefined group for quality measurement. We present a generally applicable systematic approach to defining an MCC cohort of Medicare fee-for-service beneficiaries that we developed for a national quality measure, risk-standardized rates of unplanned admissions for Accountable Care Organizations. To define the MCC cohort we: (1) identified potential chronic conditions; (2) set criteria for cohort conditions based on MCC framework and measure concept; (3) applied the criteria informed by empirical analysis, experts, and the public; (4) described "broader" and "narrower" cohorts; and (5) selected final cohort with stakeholder input. Subjects were patients with chronic conditions. Participants included 21.8 million Medicare fee-for-service beneficiaries in 2012 aged 65 years and above with ≥1 of 27 Medicare Chronic Condition Warehouse condition(s). In total, 10 chronic conditions were identified based on our criteria; 8 of these 10 were associated with notably increased admission risk when co-occurring. A broader cohort (2+ of the 8 conditions) included 4.9 million beneficiaries (23% of total cohort) with an admission rate of 70 per 100 person-years. It captured 53% of total admissions. The narrower cohort (3+ conditions) had 2.2 million beneficiaries (10%) with 100 admissions per 100 person-years and captured 32% of admissions. Most stakeholders viewed the broader cohort as best aligned with the measure concept. By systematically narrowing chronic conditions to those most relevant to the outcome and incorporating stakeholder input, we defined an MCC admission measure cohort supported by stakeholders. This approach can be used as a model for other MCC outcome measures.

  7. Defining the clinical course of multiple sclerosis

    DEFF Research Database (Denmark)

    Lublin, Fred D; Reingold, Stephen C; Cohen, Jeffrey A

    2014-01-01

    Accurate clinical course descriptions (phenotypes) of multiple sclerosis (MS) are important for communication, prognostication, design and recruitment of clinical trials, and treatment decision-making. Standardized descriptions published in 1996 based on a survey of international MS experts...

  8. Highly Chemo- and Stereoselective Transfer Semihydrogenation of Alkynes Catalyzed by a Stable, Well-defined Manganese(II) Complex

    KAUST Repository

    Brzozowska, Aleksandra; Azofra, Luis Miguel; Zubar, Viktoriia; Atodiresei, Iuliana; Cavallo, Luigi; Rueping, Magnus; El-Sepelgy, Osama

    2018-01-01

    The first example of manganese catalyzed semihydrogenation of internal alkynes to (Z)-alkenes using ammonia borane as a hydrogen donor is reported. The reaction is catalyzed by a pincer complex of the earth abundant manganese(II) salt in the absence of any additives, base or super hydride. The ammonia borane smoothly reduces the manganese pre-catalyst [Mn(II)-PNP][Cl]2 to the catalytically active species [Mn(I)-PNP]-hydride in the triplet spin state. This manganese hydride is highly stabilized by complexation with the alkyne substrate. Computational DFT analysis studies of the reaction mechanism rationalizes the origin of stereoselectivity towards formation of (Z)-alkenes.

  9. Highly Chemo- and Stereoselective Transfer Semihydrogenation of Alkynes Catalyzed by a Stable, Well-defined Manganese(II) Complex

    KAUST Repository

    Brzozowska, Aleksandra

    2018-03-30

    The first example of manganese catalyzed semihydrogenation of internal alkynes to (Z)-alkenes using ammonia borane as a hydrogen donor is reported. The reaction is catalyzed by a pincer complex of the earth abundant manganese(II) salt in the absence of any additives, base or super hydride. The ammonia borane smoothly reduces the manganese pre-catalyst [Mn(II)-PNP][Cl]2 to the catalytically active species [Mn(I)-PNP]-hydride in the triplet spin state. This manganese hydride is highly stabilized by complexation with the alkyne substrate. Computational DFT analysis studies of the reaction mechanism rationalizes the origin of stereoselectivity towards formation of (Z)-alkenes.

  10. First-Principles Prediction of Spin-Polarized Multiple Dirac Rings in Manganese Fluoride

    Science.gov (United States)

    Jiao, Yalong; Ma, Fengxian; Zhang, Chunmei; Bell, John; Sanvito, Stefano; Du, Aijun

    2017-07-01

    Spin-polarized materials with Dirac features have sparked great scientific interest due to their potential applications in spintronics. But such a type of structure is very rare and none has been fabricated. Here, we investigate the already experimentally synthesized manganese fluoride (MnF3 ) as a novel spin-polarized Dirac material by using first-principles calculations. MnF3 exhibits multiple Dirac cones in one spin orientation, while it behaves like a large gap semiconductor in the other spin channel. The estimated Fermi velocity for each cone is of the same order of magnitude as that in graphene. The 3D band structure further reveals that MnF3 possesses rings of Dirac nodes in the Brillouin zone. Such a spin-polarized multiple Dirac ring feature is reported for the first time in an experimentally realized material. Moreover, similar band dispersions can be also found in other transition metal fluorides (e.g., CoF3 , CrF3 , and FeF3 ). Our results highlight a new interesting single-spin Dirac material with promising applications in spintronics and information technologies.

  11. First-Principles Prediction of Spin-Polarized Multiple Dirac Rings in Manganese Fluoride.

    Science.gov (United States)

    Jiao, Yalong; Ma, Fengxian; Zhang, Chunmei; Bell, John; Sanvito, Stefano; Du, Aijun

    2017-07-07

    Spin-polarized materials with Dirac features have sparked great scientific interest due to their potential applications in spintronics. But such a type of structure is very rare and none has been fabricated. Here, we investigate the already experimentally synthesized manganese fluoride (MnF_{3}) as a novel spin-polarized Dirac material by using first-principles calculations. MnF_{3} exhibits multiple Dirac cones in one spin orientation, while it behaves like a large gap semiconductor in the other spin channel. The estimated Fermi velocity for each cone is of the same order of magnitude as that in graphene. The 3D band structure further reveals that MnF_{3} possesses rings of Dirac nodes in the Brillouin zone. Such a spin-polarized multiple Dirac ring feature is reported for the first time in an experimentally realized material. Moreover, similar band dispersions can be also found in other transition metal fluorides (e.g., CoF_{3}, CrF_{3}, and FeF_{3}). Our results highlight a new interesting single-spin Dirac material with promising applications in spintronics and information technologies.

  12. Welding fumes from stainless steel gas metal arc processes contain multiple manganese chemical species.

    Science.gov (United States)

    Keane, Michael; Stone, Samuel; Chen, Bean

    2010-05-01

    Fumes from a group of gas metal arc welding (GMAW) processes used on stainless steel were generated using three different metal transfer modes and four different shield gases. The objective was to identify and measure manganese (Mn) species in the fumes, and identify processes that are minimal generators of Mn species. The robotic welding system was operated in short-circuit (SC) mode (Ar/CO2 and He/Ar), axial spray (AXS) mode (Ar/O2 and Ar/CO2), and pulsed axial-spray (PAXS) mode (Ar/O2). The fumes were analyzed for Mn by a sequential extraction process followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, and by X-ray diffraction (XRD). Total elemental Mn, iron (Fe), chromium (Cr) and nickel (Ni) were separately measured after aqua regia digestion and ICP-AES analysis. Soluble Mn2+, Fe2+, Fe3+, and Ni2+ in a simple biological buffer (phosphate-buffered saline) were determined at pH 7.2 and 5.0 after 2 h incubation at 37 C by ion chromatography. Results indicate that Mn was present in soluble form, acid-soluble form, and acid-soluble form after reduction by hydroxylamine, which represents soluble Mn0 and Mn2+ compounds, other Mn2+ compounds, and (Mn3+ and Mn4+) compounds, respectively. The dominant fraction was the acid-soluble Mn2+ fraction, but results varied with the process and shield gas. Soluble Mn mass percent in the fume ranged from 0.2 to 0.9%, acid-soluble Mn2+ compounds ranged from 2.6 to 9.3%, and acid plus reducing agent-soluble (Mn3+ and Mn4+) compounds ranged from 0.6 to 5.1%. Total Mn composition ranged from 7 to 15%. XRD results showed fumes had a crystalline content of 90-99% Fe3O4, and showed evidence of multiple Mn oxides, but overlaps and weak signals limited identification. Small amounts of the Mn2+ in the fume (welding process. Mn generation rates for the fractions were tabulated, and the influence of ozone is discussed. The conclusions are that exposures to welding fumes include multiple Mn species, both

  13. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: Arsenic, manganese, fluoride, iron, and uranium

    Energy Technology Data Exchange (ETDEWEB)

    Bacquart, Thomas [Better Life Laboratories, Calais, VT (United States); Frisbie, Seth [Better Life Laboratories, Calais, VT (United States); Department of Chemistry and Biochemistry, Norwich University, Northfield, VT (United States); Mitchell, Erika [Better Life Laboratories, Calais, VT (United States); Grigg, Laurie [Department of Earth and Environmental Science, Norwich University, Northfield, VT (United States); Cole, Christopher [Department of Chemistry and Biochemistry, Norwich University, Northfield, VT (United States); Small, Colleen [Vermont Department of Health Laboratory, Burlington, VT (United States); Sarkar, Bibudhendra, E-mail: bsarkar@sickkids.ca [Department of Molecular Structure and Function, The Research Institute of The Hospital for Sick Children, University of Toronto, Toronto, Ontario (Canada); Department of Biochemistry, University of Toronto, Toronto, Ontario (Canada)

    2015-06-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  14. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: Arsenic, manganese, fluoride, iron, and uranium

    International Nuclear Information System (INIS)

    Bacquart, Thomas; Frisbie, Seth; Mitchell, Erika; Grigg, Laurie; Cole, Christopher; Small, Colleen; Sarkar, Bibudhendra

    2015-01-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  15. Characterization of a manganese ore to define the use in the fluxes synthesis for submerged arc welding

    International Nuclear Information System (INIS)

    Cruz, A.; Quintana, R.; Perdomo, L.; Garcia, L. L.; Formoso, A.; Cores, A.

    2003-01-01

    Chemical analysis, thermal analysis (DTA and TG), phase determination by X-ray diffraction and granulometric analysis of the manganese ore from the location Margarita de Cambute in the eastern part of cuba were carried out. Based on these characterization results, a flux synthesis strategy was established, comprising the definition, as a basic condition, of the MnO/SiO 2 range of values. This strategy was confirmed experimentally by obtaining a flux prototype in an electric arc furnace connected to direct current source and the carrying out of the flux in submerged arc welding tests. (Author) 26 refs

  16. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: arsenic, manganese, fluoride, iron, and uranium.

    Science.gov (United States)

    Bacquart, Thomas; Frisbie, Seth; Mitchell, Erika; Grigg, Laurie; Cole, Christopher; Small, Colleen; Sarkar, Bibudhendra

    2015-06-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  17. Fusing Multiple Satellite Datasets Toward Defining and Understanding Organized Convection

    Science.gov (United States)

    Elsaesser, G.; Del Genio, A. D.

    2017-12-01

    How do we differentiate unorganized from organized convection? We might think of organized convection as being long lasting (at least longer than the lifetime of any individual cumulus cell), clustered at larger spatial scales (>100 km), and responsible for substantial rainfall accumulation. Organized convection is sustained on such scales due to the arrangement of moist/dry and buoyant/non-buoyant mesoscale circulations. The nature of these circulations is tied to system diabatic heating profiles; in particular, the 2nd baroclinic (top-heavy), stratiform heating mode is thought to be important for organized convection maintenance/propagation. We investigate the extent to which these characteristics are jointly found in propagating convective systems. Lifecycle information comes from hi-res IR data. Diabatic heating profiles, convective fractions and rainfall are provided by GPM retrievals mapped to convective system tracks. Moisture is provided by AIRS/AMSU and passive microwave retrievals. Instead of compositing heating profile information along a system track, where information is smoothed out, we sort system heating profile structures according to their "top heaviness" and then analyze PDFs of system rainfall, system sizes, durations, convective/stratiform ratios, etc. as a function of diabatic heating structure. Perhaps contrary to expectation, we find only small differences in PDFs of rainfall rates, system sizes, and system duration for different heating profile structures. If organization is defined according to heating structures, then one possible interpretation of these results is that organization is independent of system size, duration, and many times, even lifecycle stage. Is it possible that most systems "hobble" along and exhibit varying degrees of organization, dependent on local environment moisture/buoyancy variations, unlike the archetypical MCS paradigm? This presentation will also discuss the questions posed above within the context of

  18. Multiple Voices, Multiple Realities: Self-Defined Images of Self among Adolescent Hispanic English Language Learners

    Science.gov (United States)

    Ajayi, Lasisi J.

    2006-01-01

    Acquisition of multiple identities to negotiate new forms of social participation and the concomitant attendant multiple languages and multiple cultures is "sine qua non" to success in English language learning classrooms. This study therefore, investigates how middle school Hispanic students reconceptualize their identities to negotiate…

  19. Interleukin-6 counteracts therapy-induced cellular oxidative stress in multiple myeloma by up-regulating manganese superoxide dismutase.

    Science.gov (United States)

    Brown, Charles O; Salem, Kelley; Wagner, Brett A; Bera, Soumen; Singh, Neeraj; Tiwari, Ajit; Choudhury, Amit; Buettner, Garry R; Goel, Apollina

    2012-06-15

    IL (interleukin)-6, an established growth factor for multiple myeloma cells, induces myeloma therapy resistance, but the resistance mechanisms remain unclear. The present study determines the role of IL-6 in re-establishing intracellular redox homoeostasis in the context of myeloma therapy. IL-6 treatment increased myeloma cell resistance to agents that induce oxidative stress, including IR (ionizing radiation) and Dex (dexamethasone). Relative to IR alone, myeloma cells treated with IL-6 plus IR demonstrated reduced annexin/propidium iodide staining, caspase 3 activation, PARP [poly(ADP-ribose) polymerase] cleavage and mitochondrial membrane depolarization with increased clonogenic survival. IL-6 combined with IR or Dex increased early intracellular pro-oxidant levels that were causally related to activation of NF-κB (nuclear factor κB) as determined by the ability of N-acetylcysteine to suppress both pro-oxidant levels and NF-κB activation. In myeloma cells, upon combination with hydrogen peroxide treatment, relative to TNF (tumour necrosis factor)-α, IL-6 induced an early perturbation in reduced glutathione level and increased NF-κB-dependent MnSOD (manganese superoxide dismutase) expression. Furthermore, knockdown of MnSOD suppressed the IL-6-induced myeloma cell resistance to radiation. MitoSOX Red staining showed that IL-6 treatment attenuated late mitochondrial oxidant production in irradiated myeloma cells. The present study provides evidence that increases in MnSOD expression mediate IL-6-induced resistance to Dex and radiation in myeloma cells. The results of the present study indicate that inhibition of antioxidant pathways could enhance myeloma cell responses to radiotherapy and/or chemotherapy.

  20. Relationship-Oriented Software Defined AS-Level Fast Rerouting for Multiple Link Failures

    Directory of Open Access Journals (Sweden)

    Chunxiu Li

    2015-01-01

    Full Text Available Large-scale deployments of mission-critical services have led to stringent demands on Internet routing, but frequently occurring network failures can dramatically degrade the network performance. However, Border Gateway Protocol (BGP can not react quickly to recover from them. Although extensive research has been conducted to deal with the problem, the multiple failure scenarios have never been properly addressed due to the limit of distributed control plane. In this paper, we propose a local fast reroute approach to effectively recover from multiple link failures in one administrative domain. The principle of Software Defined Networking (SDN is used to achieve the software defined AS-level fast rerouting. Considering AS relationships, efficient algorithms are proposed to automatically and dynamically find protection paths for multiple link failures; then OpenFlow forwarding rules are installed on routers to provide data forwarding continuity. Our approach is able to ensure applicability to ASes with flexibility and adaptability to multiple link failures, contributing toward improving the network performance. Through experimental results, we show that our proposal provides effective failure recovery and does not introduce significant control overhead to the network.

  1. Energy-Aware Routing in Multiple Domains Software-Defined Networks

    Directory of Open Access Journals (Sweden)

    Adriana FERNÁNDEZ-FERNÁNDEZ

    2016-12-01

    Full Text Available The growing energy consumption of communication networks has attracted the attention of the networking researchers in the last decade. In this context, the new architecture of Software-Defined Networks (SDN allows a flexible programmability, suitable for the power-consumption optimization problem. In this paper we address the issue of designing a novel distributed routing algorithm that optimizes the power consumption in large scale SDN with multiple domains. The solution proposed, called DEAR (Distributed Energy-Aware Routing, tackles the problem of minimizing the number of links that can be used to satisfy a given data traffic demand under performance constraints such as control traffic delay and link utilization. To this end, we present a complete formulation of the optimization problem that considers routing requirements for control and data plane communications. Simulation results confirm that the proposed solution enables the achievement of significant energy savings.

  2. Multiple cues add up in defining a figure on a ground.

    Science.gov (United States)

    Devinck, Frédéric; Spillmann, Lothar

    2013-01-25

    We studied the contribution of multiple cues to figure-ground segregation. Convexity, symmetry, and top-down polarity (henceforth called wide base) were used as cues. Single-cue displays as well as ambiguous stimulus patterns containing two or three cues were presented. Error rate (defined by responses to uncued stimuli) and reaction time were used to quantify the figural strength of a given cue. In the first experiment, observers were asked to report which of two regions, left or right, appeared as foreground figure. Error rate did not benefit from adding additional cues if convexity was present, suggesting that responses were based on convexity as the predominant figural determinant. However, reaction time became shorter with additional cues even if convexity was present. For example, when symmetry and wide base were added, figure-ground segregation was facilitated. In a second experiment, stimulus patterns were exposed for 150ms to rule out eye movements. Results were similar to those found in the first experiment. Both experiments suggest that under the conditions of our experiment figure-ground segregation is perceived more readily, when several cues cooperate in defining the figure. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. The role of the Parkinson's disease gene PARK9 in essential cellular pathways and the manganese homeostasis network in yeast.

    Directory of Open Access Journals (Sweden)

    Alessandra Chesi

    Full Text Available YPK9 (Yeast PARK9; also known as YOR291W is a non-essential yeast gene predicted by sequence to encode a transmembrane P-type transport ATPase. However, its substrate specificity is unknown. Mutations in the human homolog of YPK9, ATP13A2/PARK9, have been linked to genetic forms of early onset parkinsonism. We previously described a strong genetic interaction between Ypk9 and another Parkinson's disease (PD protein α-synuclein in multiple model systems, and a role for Ypk9 in manganese detoxification in yeast. In humans, environmental exposure to toxic levels of manganese causes a syndrome similar to PD and is thus an environmental risk factor for the disease. How manganese contributes to neurodegeneration is poorly understood. Here we describe multiple genome-wide screens in yeast aimed at defining the cellular function of Ypk9 and the mechanisms by which it protects cells from manganese toxicity. In physiological conditions, we found that Ypk9 genetically interacts with essential genes involved in cellular trafficking and the cell cycle. Deletion of Ypk9 sensitizes yeast cells to exposure to excess manganese. Using a library of non-essential gene deletions, we screened for additional genes involved in tolerance to excess manganese exposure, discovering several novel pathways involved in manganese homeostasis. We defined the dependence of the deletion strain phenotypes in the presence of manganese on Ypk9, and found that Ypk9 deletion modifies the manganese tolerance of only a subset of strains. These results confirm a role for Ypk9 in manganese homeostasis and illuminates cellular pathways and biological processes in which Ypk9 likely functions.

  4. Influence of multiple well defined conformations on small-angle scattering of proteins in solution.

    Science.gov (United States)

    Heller, William T

    2005-01-01

    A common structural motif for many proteins comprises rigid domains connected by a flexible hinge or linker. The flexibility afforded by these domains is important for proper function and such proteins may be able to adopt more than one conformation in solution under equilibrium conditions. Small-angle scattering of proteins in solution samples all conformations that exist in the sampled volume during the time of the measurement, providing an ensemble-averaged intensity. In this paper, the influence of sampling an ensemble of well defined protein structures on the small-angle solution scattering intensity profile is examined through common analysis methods. Two tests were performed using simulated data: one with the extended and collapsed states of the bilobal calcium-binding protein calmodulin and the second with the catalytic subunit of protein kinase A, which has two globular domains connected by a glycine hinge. In addition to analyzing the simulated data for the radii of gyration Rg, distance distribution function P(r) and particle volume, shape restoration was applied to the simulated data. Rg and P(r) of the ensemble profiles could be easily mistaken for a single intermediate state. The particle volumes and models of the ensemble intensity profiles show that some indication of multiple conformations exists in the case of calmodulin, which manifests an enlarged volume and shapes that are clear superpositions of the conformations used. The effect on the structural parameters and models is much more subtle in the case of the catalytic subunit of protein kinase A. Examples of how noise influences the data and analyses are also presented. These examples demonstrate the loss of the indications of multiple conformations in cases where even broad distributions of structures exist. While the tests using calmodulin show that the ensemble states remain discernible from the other ensembles tested or a single partially collapsed state, the tests performed using the

  5. Interleukin-6 counteracts therapy-induced cellular oxidative stress in multiple myeloma by up-regulating manganese superoxide dismutase

    OpenAIRE

    Brown, Charles O.; Salem, Kelley; Wagner, Brett A.; Bera, Soumen; Singh, Neeraj; Tiwari, Ajit; Choudhury, Amit; Buettner, Garry R.; Goel, Apollina

    2012-01-01

    IL (interleukin)-6, an established growth factor for multiple myeloma cells, induces myeloma therapy resistance, but the resistance mechanisms remain unclear. The present study determines the role of IL-6 in re-establishing intracellular redox homoeostasis in the context of myeloma therapy. IL-6 treatment increased myeloma cell resistance to agents that induce oxidative stress, including IR (ionizing radiation) and Dex (dexamethasone). Relative to IR alone, myeloma cells treated with IL-6 plu...

  6. GWAS of clinically defined gout and subtypes identifies multiple susceptibility loci that include urate transporter genes

    NARCIS (Netherlands)

    Nakayama, A.; Nakaoka, H.; Yamamoto, K.; Sakiyama, M.; Shaukat, A.; Toyoda, Y.; Okada, Y.; Kamatani, Y.; Nakamura, T.; Takada, T.; Inoue, K.; Yasujima, T.; Yuasa, H.; Shirahama, Y.; Nakashima, H.; Shimizu, S.; Higashino, T.; Kawamura, Y.; Ogata, H.; Kawaguchi, M.; Ohkawa, Y.; Danjoh, I.; Tokumasu, A.; Ooyama, K.; Ito, T.; Kondo, T.; Wakai, K.; Stiburkova, B.; Pavelka, K.; Stamp, L.K.; Dalbeth, N.; Sakurai, Y.; Suzuki, H; Hosoyamada, M.; Fujimori, S.; Yokoo, T.; Hosoya, T.; Inoue, I.; Takahashi, A.; Kubo, M.; Ooyama, H.; Shimizu, T.; Ichida, K.; Shinomiya, N.; Merriman, T.R.; Matsuo, H.; Andres, M; Joosten, L.A.; Janssen, M.C.H.; Jansen, T.L.; Liote, F.; Radstake, T.R.; Riches, P.L.; So, A.; Tauches, A.K.

    2017-01-01

    OBJECTIVE: A genome-wide association study (GWAS) of gout and its subtypes was performed to identify novel gout loci, including those that are subtype-specific. METHODS: Putative causal association signals from a GWAS of 945 clinically defined gout cases and 1213 controls from Japanese males were

  7. Defining hotspots of characteristic species for multiple taxonomic groups in the Netherlands

    NARCIS (Netherlands)

    Schouten, M.A.; Barendregt, A.; Verweij, P.A.; Kalkman, V.J.; Kleukers, R.J.M.C.; Lenders, H.J.R.; Siebel, H.N.

    2010-01-01

    Biogeographical zonation based on single taxa poses major limitations on planning for nature conservation. This paper identifies biogeographical patterns of multiple taxa in the Netherlands, where no endemics are present at species level, on the basis of characteristic species. We used occurrence

  8. Painting with the Multiple Intelligences: Defining Student Success and Permanence in Art Class

    Science.gov (United States)

    Taspinar, Seyda Eraslan; Kaya, Ali

    2016-01-01

    Objectives of the study are to determine the effect of teaching based on multiple intelligence theory (TBMIT) in visual arts class on student success and permanence. Experimental design is used in the study. Study group is composed of students at 8th grade in 2012-2013 educational term at Atatürk Secondary School in Igdir city centre. Experimental…

  9. GWAS of clinically defined gout and subtypes identifies multiple susceptibility loci that include urate transporter genes

    OpenAIRE

    Nakayama, Akiyoshi; Nakaoka, Hirofumi; Yamamoto, Ken; Sakiyama, Masayuki; Shaukat, Amara; Toyoda, Yu; Okada, Yukinori; Kamatani, Yoichiro; Nakamura, Takahiro; Takada, Tappei; Inoue, Katsuhisa; Yasujima, Tomoya; Yuasa, Hiroaki; Shirahama, Yuko; Nakashima, Hiroshi

    2016-01-01

    Objective A genome-wide association study (GWAS) of gout and its subtypes was performed to identify novel gout loci, including those that are subtype-specific. Methods Putative causal association signals from a GWAS of 945 clinically defined gout cases and 1213 controls from Japanese males were replicated with 1396 cases and 1268 controls using a custom chip of 1961 single nucleotide polymorphisms (SNPs). We also first conducted GWASs of gout subtypes. Replication with Caucasian and New Zeala...

  10. Defining ecological and economical hydropoweroperations: a framework for managing dam releasesto meet multiple conflicting objectives

    Science.gov (United States)

    Irwin, Elise R.

    2014-01-01

    Hydroelectric dams are a flexible source of power, provide flood control, and contribute to the economic growth of local communities through real-estate and recreation. Yet the impoundment of rivers can alter and fragment miles of critical riverine habitat needed for other competing needs such as downstream consumptive water use, fish and wildlife population viability, or other forms of recreation. Multiple conflicting interests can compromise progressive management especially with recognized uncertainties related to whether management actions will fulfill the objectives of policy makers, resource managers and/or facility owners. Decision analytic tools were used in a stakeholder-driven process to develop and implement a template for evaluation and prediction of the effects of water resource management of multiple-use systems under the context provided by R.L. Harris Dam on the Tallapoosa River, Alabama, USA. The approach provided a transparent and structured framework for decision-making and incorporated both existing and new data to meet multiple management objectives. Success of the template has been evaluated by the stakeholder governing body in an adaptive resource management framework since 2005 and is ongoing. Consequences of management of discharge at the dam were evaluated annually relative to stakeholder satisfaction to allow for adjustment of both management scenarios and objectives. This template can be applied to attempt to resolve conflict inherent in many dam-regulated systems where management decisions impact diverse values of stakeholders.

  11. Defining and Developing "Critical Thinking" Through Devising and Testing Multiple Explanations of the Same Phenomenon

    Science.gov (United States)

    Etkina, Eugenia; Planinšič, Gorazd

    2015-10-01

    Most physics teachers would agree that one of the main reasons for her/his students to take physics is to learn to think critically. However, for years we have been assessing our students mostly on the knowledge of physics content (conceptually and quantitatively). Only recently have science educators started moving systematically towards achieving and assessing this critical thinking goal. In this paper we seek to show how guiding students to devise and test multiple explanations of observed phenomena can be used to improve their critical thinking.

  12. Overlapping effector interfaces define the multiple functions of the HIV-1 Nef polyproline helix

    Directory of Open Access Journals (Sweden)

    Kuo Lillian S

    2012-05-01

    Full Text Available Abstract Background HIV-1 Nef is a multifunctional protein required for full pathogenicity of the virus. As Nef has no known enzymatic activity, it necessarily functions through protein-protein interaction interfaces. A critical Nef protein interaction interface is centered on its polyproline segment (P69VRPQVPLRP78 which contains the helical SH3 domain binding protein motif, PXXPXR. We hypothesized that any Nef-SH3 domain interactions would be lost upon mutation of the prolines or arginine of PXXPXR. Further, mutation of the non-motif “X” residues, (Q73, V74, and L75 would give altered patterns of inhibition for different Nef/SH3 domain protein interactions. Results We found that mutations of either of the prolines or the arginine of PXXPXR are defective for Nef-Hck binding, Nef/activated PAK2 complex formation and enhancement of virion infectivity (EVI. Mutation of the non-motif “X” residues (Q, V and L gave similar patterns of inhibition for Nef/activated PAK2 complex formation and EVI which were distinct from the pattern for Hck binding. These results implicate an SH3 domain containing protein other than Hck for Nef/activated PAK2 complex formation and EVI. We have also mutated Nef residues at the N-and C-terminal ends of the polyproline segment to explore interactions outside of PXXPXR. We discovered a new locus GFP/F (G67, F68, P69 and F90 that is required for Nef/activated PAK2 complex formation and EVI. MHC Class I (MHCI downregulation was only partially inhibited by mutating the PXXPXR motif residues, but was fully inhibited by mutating the C-terminal P78. Further, we observed that MHCI downregulation strictly requires G67 and F68. Our mutational analysis confirms the recently reported structure of the complex between Nef, AP-1 μ1 and the cytoplasmic tail of MHCI, but does not support involvement of an SH3 domain protein in MHCI downregulation. Conclusion Nef has evolved to be dependent on interactions with multiple SH3 domain

  13. 3D printing of tablets containing multiple drugs with defined release profiles.

    Science.gov (United States)

    Khaled, Shaban A; Burley, Jonathan C; Alexander, Morgan R; Yang, Jing; Roberts, Clive J

    2015-10-30

    We have employed three-dimensional (3D) extrusion-based printing as a medicine manufacturing technique for the production of multi-active tablets with well-defined and separate controlled release profiles for three different drugs. This 'polypill' made by a 3D additive manufacture technique demonstrates that complex medication regimes can be combined in a single tablet and that it is viable to formulate and 'dial up' this single tablet for the particular needs of an individual. The tablets used to illustrate this concept incorporate an osmotic pump with the drug captopril and sustained release compartments with the drugs nifedipine and glipizide. This combination of medicines could potentially be used to treat diabetics suffering from hypertension. The room temperature extrusion process used to print the formulations used excipients commonly employed in the pharmaceutical industry. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and X-ray powder diffraction (XRPD) were used to assess drug-excipient interaction. The printed formulations were evaluated for drug release using USP dissolution testing. We found that the captopril portion showed the intended zero order drug release of an osmotic pump and noted that the nifedipine and glipizide portions showed either first order release or Korsmeyer-Peppas release kinetics dependent upon the active/excipient ratio used. Copyright © 2015. Published by Elsevier B.V.

  14. GWAS of clinically defined gout and subtypes identifies multiple susceptibility loci that include urate transporter genes.

    Science.gov (United States)

    Nakayama, Akiyoshi; Nakaoka, Hirofumi; Yamamoto, Ken; Sakiyama, Masayuki; Shaukat, Amara; Toyoda, Yu; Okada, Yukinori; Kamatani, Yoichiro; Nakamura, Takahiro; Takada, Tappei; Inoue, Katsuhisa; Yasujima, Tomoya; Yuasa, Hiroaki; Shirahama, Yuko; Nakashima, Hiroshi; Shimizu, Seiko; Higashino, Toshihide; Kawamura, Yusuke; Ogata, Hiraku; Kawaguchi, Makoto; Ohkawa, Yasuyuki; Danjoh, Inaho; Tokumasu, Atsumi; Ooyama, Keiko; Ito, Toshimitsu; Kondo, Takaaki; Wakai, Kenji; Stiburkova, Blanka; Pavelka, Karel; Stamp, Lisa K; Dalbeth, Nicola; Sakurai, Yutaka; Suzuki, Hiroshi; Hosoyamada, Makoto; Fujimori, Shin; Yokoo, Takashi; Hosoya, Tatsuo; Inoue, Ituro; Takahashi, Atsushi; Kubo, Michiaki; Ooyama, Hiroshi; Shimizu, Toru; Ichida, Kimiyoshi; Shinomiya, Nariyoshi; Merriman, Tony R; Matsuo, Hirotaka

    2017-05-01

    A genome-wide association study (GWAS) of gout and its subtypes was performed to identify novel gout loci, including those that are subtype-specific. Putative causal association signals from a GWAS of 945 clinically defined gout cases and 1213 controls from Japanese males were replicated with 1396 cases and 1268 controls using a custom chip of 1961 single nucleotide polymorphisms (SNPs). We also first conducted GWASs of gout subtypes. Replication with Caucasian and New Zealand Polynesian samples was done to further validate the loci identified in this study. In addition to the five loci we reported previously, further susceptibility loci were identified at a genome-wide significance level (pgout cases, and NIPAL1 and FAM35A for the renal underexcretion gout subtype. While NIPAL1 encodes a magnesium transporter, functional analysis did not detect urate transport via NIPAL1, suggesting an indirect association with urate handling. Localisation analysis in the human kidney revealed expression of NIPAL1 and FAM35A mainly in the distal tubules, which suggests the involvement of the distal nephron in urate handling in humans. Clinically ascertained male patients with gout and controls of Caucasian and Polynesian ancestries were also genotyped, and FAM35A was associated with gout in all cases. A meta-analysis of the three populations revealed FAM35A to be associated with gout at a genome-wide level of significance (p meta =3.58×10 -8 ). Our findings including novel gout risk loci provide further understanding of the molecular pathogenesis of gout and lead to a novel concept for the therapeutic target of gout/hyperuricaemia. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks.

    Science.gov (United States)

    Shen, Yiwen; Hattink, Maarten H N; Samadi, Payman; Cheng, Qixiang; Hu, Ziyiz; Gazman, Alexander; Bergman, Keren

    2018-04-16

    Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. We present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly network testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 µs control plane latency for data-center and high performance computing platforms.

  16. Using a modification of the Clavien-Dindo system accounting for readmissions and multiple interventions: defining quality for pancreaticoduodenectomy.

    Science.gov (United States)

    Baker, Marshall S; Sherman, Karen L; Stocker, Susan J; Hayman, Amanda V; Bentrem, David J; Prinz, Richard A; Talamonti, Mark S

    2014-09-01

    The Clavien-Dindo system (CD) does not change the grade assigned a complication when multiple readmissions or interventions are required to manage a complication. We apply a modification of CD accounting for readmissions and interventions to pancreaticoduodenectomy (PD). PDs done between 1999 and 2009 were reviewed. CD grade IIIa complications requiring more than one intervention and II and IIIa complications requiring significantly prolonged lengths of stay including all 90-day readmissions were classified severe-adverse-postoperative-outcomes (SAPO). CD IIIb, IV, and V complications were also classified SAPOs. All other complications were considered minor-adverse-postoperative-outcomes (MAPO). Four-hundred forty three of 490 PD patients (90.4%) had either no complication or a complication of low to moderate CD grade (I, II, IIIa). When reclassified by the new metric, 92 patient-outcomes (19%) were upgraded from CD II or IIIa to SAPO. One-hundred thirty nine patients (28.4%) had a SAPO. Multivariable regression identified age >75 years, pylorus preservation and operative blood loss >1,500 ml as predictors of SAPO. Age was not associated with poor outcome using the unmodified CD system. Established systems may under-grade the severity of some complications following PD. We define a procedure-specific modification of CD accounting for readmissions and multiple interventions. Using this modification, advanced age, pylorus preservation, and significant blood loss are associated with poor outcome. © 2014 Wiley Periodicals, Inc.

  17. Gastroprotective Properties of Manganese Chloride on Acetic Acid

    African Journals Online (AJOL)

    Dr Olaleye

    Drugs with multiple mechanisms of protective action may be effective in minimizing ... that Manganese had dose and treatment duration dependent effect on healing of ulcerated stomach. .... The stomach was bathed with normal saline ..... Arnaud, J., and Favier, A. (1995): "Copper, iron, manganese ... Experimental Toxic.

  18. In-depth analysis of protein inference algorithms using multiple search engines and well-defined metrics.

    Science.gov (United States)

    Audain, Enrique; Uszkoreit, Julian; Sachsenberg, Timo; Pfeuffer, Julianus; Liang, Xiao; Hermjakob, Henning; Sanchez, Aniel; Eisenacher, Martin; Reinert, Knut; Tabb, David L; Kohlbacher, Oliver; Perez-Riverol, Yasset

    2017-01-06

    In mass spectrometry-based shotgun proteomics, protein identifications are usually the desired result. However, most of the analytical methods are based on the identification of reliable peptides and not the direct identification of intact proteins. Thus, assembling peptides identified from tandem mass spectra into a list of proteins, referred to as protein inference, is a critical step in proteomics research. Currently, different protein inference algorithms and tools are available for the proteomics community. Here, we evaluated five software tools for protein inference (PIA, ProteinProphet, Fido, ProteinLP, MSBayesPro) using three popular database search engines: Mascot, X!Tandem, and MS-GF+. All the algorithms were evaluated using a highly customizable KNIME workflow using four different public datasets with varying complexities (different sample preparation, species and analytical instruments). We defined a set of quality control metrics to evaluate the performance of each combination of search engines, protein inference algorithm, and parameters on each dataset. We show that the results for complex samples vary not only regarding the actual numbers of reported protein groups but also concerning the actual composition of groups. Furthermore, the robustness of reported proteins when using databases of differing complexities is strongly dependant on the applied inference algorithm. Finally, merging the identifications of multiple search engines does not necessarily increase the number of reported proteins, but does increase the number of peptides per protein and thus can generally be recommended. Protein inference is one of the major challenges in MS-based proteomics nowadays. Currently, there are a vast number of protein inference algorithms and implementations available for the proteomics community. Protein assembly impacts in the final results of the research, the quantitation values and the final claims in the research manuscript. Even though protein

  19. Genome-wide association study of clinically defined gout identifies multiple risk loci and its association with clinical subtypes

    OpenAIRE

    Matsuo, Hirotaka; Yamamoto, Ken; Nakaoka, Hirofumi; Nakayama, Akiyoshi; Sakiyama, Masayuki; Chiba, Toshinori; Takahashi, Atsushi; Nakamura, Takahiro; Nakashima, Hiroshi; Takada, Yuzo; Danjoh, Inaho; Shimizu, Seiko; Abe, Junko; Kawamura, Yusuke; Terashige, Sho

    2015-01-01

    Objective Gout, caused by hyperuricaemia, is a multifactorial disease. Although genome-wide association studies (GWASs) of gout have been reported, they included self-reported gout cases in which clinical information was insufficient. Therefore, the relationship between genetic variation and clinical subtypes of gout remains unclear. Here, we first performed a GWAS of clinically defined gout cases only. Methods A GWAS was conducted with 945 patients with clinically defined gout and 1213 contr...

  20. Manganese in silicon carbide

    Energy Technology Data Exchange (ETDEWEB)

    Linnarsson, M.K., E-mail: marga@kth.se [Royal Institute of Technology, School of Information and Communication Technology, P.O. Box E229, SE-16440 Kista-Stockhom (Sweden); Hallen, A. [Royal Institute of Technology, School of Information and Communication Technology, P.O. Box E229, SE-16440 Kista-Stockhom (Sweden)

    2012-02-15

    Structural disorder and relocation of implanted Mn in semi-insulating 4H-SiC has been studied. Subsequent heat treatment of Mn implanted samples has been performed in the temperature range 1400-2000 Degree-Sign C. The depth distribution of manganese is recorded by secondary ion mass spectrometry. Rutherford backscattering spectrometry has been employed for characterization of crystal disorder. Ocular inspection of color changes of heat-treated samples indicates that a large portion of the damage has been annealed. However, Rutherford backscattering shows that after heat treatment, most disorder from the implantation remains. Less disorder is observed in the [0 0 0 1] channel direction compared to [112{sup Macron }3] channel direction. A substantial rearrangement of manganese is observed in the implanted region. No pronounced manganese diffusion deeper into the sample is recorded.

  1. Manganese in silicon carbide

    International Nuclear Information System (INIS)

    Linnarsson, M.K.; Hallén, A.

    2012-01-01

    Structural disorder and relocation of implanted Mn in semi-insulating 4H–SiC has been studied. Subsequent heat treatment of Mn implanted samples has been performed in the temperature range 1400–2000 °C. The depth distribution of manganese is recorded by secondary ion mass spectrometry. Rutherford backscattering spectrometry has been employed for characterization of crystal disorder. Ocular inspection of color changes of heat-treated samples indicates that a large portion of the damage has been annealed. However, Rutherford backscattering shows that after heat treatment, most disorder from the implantation remains. Less disorder is observed in the [0 0 0 1] channel direction compared to [112 ¯ 3] channel direction. A substantial rearrangement of manganese is observed in the implanted region. No pronounced manganese diffusion deeper into the sample is recorded.

  2. How do stakeholders from multiple hierarchical levels of a large provincial health system define engagement? A qualitative study.

    Science.gov (United States)

    Norris, Jill M; White, Deborah E; Nowell, Lorelli; Mrklas, Kelly; Stelfox, Henry T

    2017-08-01

    Engaging stakeholders from varied organizational levels is essential to successful healthcare quality improvement. However, engagement has been hard to achieve and to measure across diverse stakeholders. Further, current implementation science models provide little clarity about what engagement means, despite its importance. The aim of this study was to understand how stakeholders of healthcare improvement initiatives defined engagement. Participants (n = 86) in this qualitative thematic study were purposively sampled for individual interviews. Participants included leaders, core members, frontline clinicians, support personnel, and other stakeholders of Strategic Clinical Networks in Alberta Health Services, a Canadian provincial health system with over 108,000 employees. We used an iterative thematic approach to analyze participants' responses to the question, "How do you define engagement?" Regardless of their organizational role, participants defined engagement through three interrelated themes. First, engagement was active participation from willing and committed stakeholders, with levels that ranged from information sharing to full decision-making. Second, engagement centered on a shared decision-making process about meaningful change for everyone "around the table," those who are most impacted. Third, engagement was two-way interactions that began early in the change process, where exchanges were respectful and all stakeholders felt heard and understood. This study highlights the commonalities of how stakeholders in a large healthcare system defined engagement-a shared understanding and terminology-to guide and improve stakeholder engagement. Overall, engagement was an active and committed decision-making about a meaningful problem through respectful interactions and dialog where everyone's voice is considered. Our results may be used in conjunction with current implementation models to provide clarity about what engagement means and how to engage various

  3. Manganese dipyridoxyl diphosphate:

    DEFF Research Database (Denmark)

    H, Brurok; Ardenkjær-Larsen, Jan Henrik; G, Hansson

    1999-01-01

    Manganese dipyridoxyl diphosphate (MnDPDP) is a contrast agent for magnetic resonance imaging (MRI) of the liver. Aims of the study were to examine if MnDPDP possesses superoxide dismutase (SOD) mimetic activity in vitro, and if antioxidant protection can be demonstrated in an ex vivo rat heart...

  4. Genome-wide association study of clinically defined gout identifies multiple risk loci and its association with clinical subtypes.

    Science.gov (United States)

    Matsuo, Hirotaka; Yamamoto, Ken; Nakaoka, Hirofumi; Nakayama, Akiyoshi; Sakiyama, Masayuki; Chiba, Toshinori; Takahashi, Atsushi; Nakamura, Takahiro; Nakashima, Hiroshi; Takada, Yuzo; Danjoh, Inaho; Shimizu, Seiko; Abe, Junko; Kawamura, Yusuke; Terashige, Sho; Ogata, Hiraku; Tatsukawa, Seishiro; Yin, Guang; Okada, Rieko; Morita, Emi; Naito, Mariko; Tokumasu, Atsumi; Onoue, Hiroyuki; Iwaya, Keiichi; Ito, Toshimitsu; Takada, Tappei; Inoue, Katsuhisa; Kato, Yukio; Nakamura, Yukio; Sakurai, Yutaka; Suzuki, Hiroshi; Kanai, Yoshikatsu; Hosoya, Tatsuo; Hamajima, Nobuyuki; Inoue, Ituro; Kubo, Michiaki; Ichida, Kimiyoshi; Ooyama, Hiroshi; Shimizu, Toru; Shinomiya, Nariyoshi

    2016-04-01

    Gout, caused by hyperuricaemia, is a multifactorial disease. Although genome-wide association studies (GWASs) of gout have been reported, they included self-reported gout cases in which clinical information was insufficient. Therefore, the relationship between genetic variation and clinical subtypes of gout remains unclear. Here, we first performed a GWAS of clinically defined gout cases only. A GWAS was conducted with 945 patients with clinically defined gout and 1213 controls in a Japanese male population, followed by replication study of 1048 clinically defined cases and 1334 controls. Five gout susceptibility loci were identified at the genome-wide significance level (pgenes (ABCG2 and SLC2A9) and additional genes: rs1260326 (p=1.9×10(-12); OR=1.36) of GCKR (a gene for glucose and lipid metabolism), rs2188380 (p=1.6×10(-23); OR=1.75) of MYL2-CUX2 (genes associated with cholesterol and diabetes mellitus) and rs4073582 (p=6.4×10(-9); OR=1.66) of CNIH-2 (a gene for regulation of glutamate signalling). The latter two are identified as novel gout loci. Furthermore, among the identified single-nucleotide polymorphisms (SNPs), we demonstrated that the SNPs of ABCG2 and SLC2A9 were differentially associated with types of gout and clinical parameters underlying specific subtypes (renal underexcretion type and renal overload type). The effect of the risk allele of each SNP on clinical parameters showed significant linear relationships with the ratio of the case-control ORs for two distinct types of gout (r=0.96 [p=4.8×10(-4)] for urate clearance and r=0.96 [p=5.0×10(-4)] for urinary urate excretion). Our findings provide clues to better understand the pathogenesis of gout and will be useful for development of companion diagnostics. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. Manganese, Metallogenium, and Martian Microfossils

    Science.gov (United States)

    Stein, L. Y.; Nealson, K. H.

    1999-01-01

    Manganese could easily be considered an abundant element in the Martian regolith, assuming that the composition of martian meteorites reflects the composition of the planet. Mineralogical analyses of 5 SNC meteorites have revealed an average manganese oxide concentration of 0.48%, relative to the 0.1% concentration of manganese found in the Earth's crust. On the Earth, the accumulation of manganese oxides in oceans, soils, rocks, sedimentary ores, fresh water systems, and hydrothermal vents can be largely attributed to microbial activity. Manganese is also a required trace nutrient for most life forms and participates in many critical enzymatic reactions such as photosynthesis. The wide-spread process of bacterial manganese cycling on Earth suggests that manganese is an important element to both geology and biology. Furthermore, there is evidence that bacteria can be fossilized within manganese ores, implying that manganese beds may be good repositories for preserved biomarkers. A particular genus of bacteria, known historically as Metallogenium, can form star-shaped manganese oxide minerals (called metallogenium) through the action of manganese oxide precipitation along its surface. Fossilized structures that resemble metallogenium have been found in Precambrian sedimentary formations and in Cretaceous-Paleogene cherts. The Cretaceous-Paleogene formations are highly enriched in manganese and have concentrations of trace elements (Fe, Zn, Cu, and Co) similar to modern-day manganese oxide deposits in marine environments. The appearance of metallogenium-like fossils associated with manganese deposits suggests that bacteria may be preserved within the minerals that they form. Additional information is contained in the original extended abstract.

  6. Defining key features of the broad autism phenotype: a comparison across parents of multiple- and single-incidence autism families.

    Science.gov (United States)

    Losh, Molly; Childress, Debra; Lam, Kristen; Piven, Joseph

    2008-06-05

    This study examined the frequency of personality, language, and social-behavioral characteristics believed to comprise the broad autism phenotype (BAP), across families differing in genetic liability to autism. We hypothesized that within this unique sample comprised of multiple-incidence autism families (MIAF), single-incidence autism families (SIAF), and control Down syndrome families (DWNS), a graded expression would be observed for the principal characteristics conferring genetic susceptibility to autism, in which such features would express most profoundly among parents from MIAFs, less strongly among SIAFs, and least of all among comparison parents from DWNS families, who should display population base rates. Analyses detected linear expression of traits in line with hypotheses, and further suggested differential intrafamilial expression across family types. In the vast majority of MIAFs both parents displayed BAP characteristics, whereas within SIAFs, it was equally likely that one, both, or neither parent show BAP features. The significance of these findings is discussed in relation to etiologic mechanisms in autism and relevance to molecular genetic studies. (c) 2007 Wiley-Liss, Inc.

  7. Use of multiple chemical tracers to define habitat use of Indo-Pacific mangrove crab, Scylla serrata (Decapoda: Portunidae)

    Science.gov (United States)

    Demopoulos, A.W.J.; Cormier, N.; Ewel, K.C.; Fry, B.

    2008-01-01

    The mangrove or mud crab, Scylla serrata, is an important component of mangrove fisheries throughout the Indo-Pacific. Understanding crab diets and habitat use should assist in managing these fisheries and could provide additional justification for conservation of the mangrove ecosystem itself. We used multiple chemical tracers to test whether crab movements were restricted to local mangrove forests, or extended to include adjacent seagrass beds and reef flats. We sampled three mangrove forests on the island of Kosrae in the Federated States of Micronesia at Lelu Harbor, Okat River, and Utwe tidal channel. Samples of S. serrata and likely food sources were analyzed for stable carbon (??13C), nitrogen (??15N), and sulfur (??34S) isotopes. Scylla serrata tissues also were analyzed for phosphorus (P), cations (K, Ca, Mg, Na), and trace elements (Mn, Fe, Cu, Zn, and B). Discriminant analysis indicated that at least 87% of the crabs remain in each site as distinct populations. Crab stable isotope values indicated potential differences in habitat use within estuaries. Values for ??13C and ??34S in crabs from Okat and Utwe were low and similar to values expected from animals feeding within mangrove forests, e.g., feeding on infauna that had average ??13C values near -26.5???. In contrast, crabs from Lelu had higher ?? 13C and ??34S values, with average values of -21.8 and 7.8???, respectively. These higher isotope values are consistent with increased crab foraging on reef flats and seagrasses. Given that S. serrata have been observed feeding on adjacent reef and seagrass environments on Kosrae, it is likely that they move in and out of the mangroves for feeding. Isotope mixing model results support these conclusions, with the greatest mangrove ecosystem contribution to S. serrata diet occurring in the largest mangrove forests. Conserving larger island mangrove forests (> 1 km deep) appears to support crab foraging activities. ?? 2007 Coastal and Estuarine Research

  8. Identification of markers that functionally define a quiescent multiple myeloma cell sub-population surviving bortezomib treatment

    International Nuclear Information System (INIS)

    Adomako, Alfred; Calvo, Veronica; Biran, Noa; Osman, Keren; Chari, Ajai; Paton, James C; Paton, Adrienne W; Moore, Kateri; Schewe, Denis M; Aguirre-Ghiso, Julio A

    2015-01-01

    The mechanisms allowing residual multiple myeloma (MM) cells to persist after bortezomib (Bz) treatment remain unclear. We hypothesized that studying the biology of bortezomib-surviving cells may reveal markers to identify these cells and survival signals to target and kill residual MM cells. We used H2B-GFP label retention, biochemical tools and in vitro and in vivo experiments to characterize growth arrest and the unfolded protein responses in quiescent Bz-surviving cells. We also tested the effect of a demethylating agent, 5-Azacytidine, on Bz-induced quiescence and whether inhibiting the chaperone GRP78/BiP (henceforth GRP78) with a specific toxin induced apoptosis in Bz-surviving cells. Finally, we used MM patient samples to test whether GRP78 levels might associate with disease progression. Statistical analysis employed t-test and Mann-Whitney tests at a 95% confidence. We report that Bz-surviving MM cells in vitro and in vivo enter quiescence characterized by p21 CIP1 upregulation. Bz-surviving MM cells also downregulated CDK6, Ki67 and P-Rb. H2B-GFP label retention showed that Bz-surviving MM cells are either slow-cycling or deeply quiescent. The Bz-induced quiescence was stabilized by low dose (500nM) of 5-azacytidine (Aza) pre-treatment, which also potentiated the initial Bz-induced apoptosis. We also found that expression of GRP78, an unfolded protein response (UPR) survival factor, persisted in MM quiescent cells. Importantly, GRP78 downregulation using a specific SubAB bacterial toxin killed Bz-surviving MM cells. Finally, quantification of Grp78 high /CD138+ MM cells from patients suggested that high levels correlated with progressive disease. We conclude that Bz-surviving MM cells display a GRP78 HIGH /p21 HIGH /CDK6 LOW /P-Rb LOW profile, and these markers may identify quiescent MM cells capable of fueling recurrences. We further conclude that Aza + Bz treatment of MM may represent a novel strategy to delay recurrences by enhancing Bz

  9. Defining Persistent Hotspots: Areas That Fail to Decrease Meaningfully in Prevalence after Multiple Years of Mass Drug Administration with Praziquantel for Control of Schistosomiasis.

    Science.gov (United States)

    Kittur, Nupur; Binder, Sue; Campbell, Carl H; King, Charles H; Kinung'hi, Safari; Olsen, Annette; Magnussen, Pascal; Colley, Daniel G

    2017-12-01

    Preventive chemotherapy with praziquantel for schistosomiasis morbidity control is commonly done by mass drug administration (MDA). MDA regimen is usually based on prevalence in a given area, and effectiveness is evaluated by decreases in prevalence and/or intensity of infection after several years of implementation. Multiple studies and programs now find that even within well-implemented, multiyear, annual MDA programs there often remain locations that do not decline in prevalence and/or intensity to expected levels. We term such locations "persistent hotspots." To study and address persistent hotspots, investigators and neglected tropical disease (NTD) program managers need to define them based on changes in prevalence and/or intensity. But how should the data be analyzed to define a persistent hotspot? We have analyzed a dataset from an operational research study in western Tanzania after three annual MDAs using four different approaches to define persistent hotspots. The four approaches are 1) absolute percent change in prevalence; 2) percent change in prevalence; 3) change in World Health Organization guideline categories; 4) change (absolute or percent) in both prevalence and intensity. We compare and contrast the outcomes of these analyses. Our intent is to show how the same dataset yields different numbers of persistent hotspots depending on the approach used to define them. We suggest that investigators and NTD program managers use the approach most suited for their study or program, but whichever approach is used, it should be clearly stated so that comparisons can be made within and between studies and programs.

  10. Defining a set of standardised outcome measures for newly diagnosed patients with multiple myeloma using the Delphi consensus method: the IMPORTA project.

    Science.gov (United States)

    Blade, Joan; Calleja, Miguel Ángel; Lahuerta, Juan José; Poveda, José Luis; de Paz, Héctor David; Lizán, Luis

    2018-02-22

    To define a standard set of outcomes and the most appropriate instruments to measure them for managing newly diagnosed patients with multiple myeloma (MM). A literature review and five discussion groups facilitated the design of two-round Delphi questionnaire. Delphi panellists (haematologists, hospital pharmacists and patients) were identified by the scientific committee, the Spanish Program of Haematology Treatments Foundation, the Spanish Society of Hospital Pharmacies and the Spanish Community of Patients with MM. Panellist's perception about outcomes' suitability and feasibility of use was assessed on a seven-point Likert scale. Consensus was reached when at least 75% of the respondents reached agreement or disagreement. A scientific committee led the project. Fifty-one and 45 panellists participated in the first and second Delphi rounds, respectively. Consensus was reached to use overall survival, progression-free survival, minimal residual disease and treatment response to assess survival and disease control. Panellists agreed to measure health-related quality of life, pain, performance status, fatigue, psychosocial status, symptoms, self-perception on body image, sexuality and preferences/satisfaction. However, panellist did not reach consensus about the feasibility of assessing in routine practice psychosocial status, symptoms, self-perception on body image and sexuality. Consensus was reached to collect patient-reported outcomes through the European Organisation for the Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ) Core questionnaire 30 (C30), three items from EORTC-QLQ-Multiple Myeloma (MY20) and EORTC-QLQ-Breast Cancer (BR23), pain Visual Analogue Scale, Morisky-Green and ad hoc questions about patients' preferences/satisfaction. A consensual standard set of outcomes for managing newly diagnosed patients with MM has been defined. The feasibility of its implementation in routine practice will be assessed in a future pilot

  11. Microwave Production of Manganese from Manganese (IV) Oxide ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... energy consumption occurs in the upper part of the ferromanganese furnace ... The pre-reduction of manganese ores by carbon has been investigated by Abdel ..... Awaso Bauxite Ore using Waste Pure Water. Sachets as ...

  12. Manganese deficiency in plants

    DEFF Research Database (Denmark)

    Schmidt, Sidsel Birkelund; Jensen, Poul Erik; Husted, Søren

    2016-01-01

    Manganese (Mn) is an essential plant micronutrient with an indispensable function as a catalyst in the oxygen-evolving complex (OEC) of photosystem II (PSII). Even so, Mn deficiency frequently occurs without visual leaf symptoms, thereby masking the distribution and dimension of the problem...... restricting crop productivity in many places of the world. Hence, timely alleviation of latent Mn deficiency is a challenge in promoting plant growth and quality. We describe here the key mechanisms of Mn deficiency in plants by focusing on the impact of Mn on PSII stability and functionality. We also address...... the mechanisms underlying the differential tolerance towards Mn deficiency observed among plant genotypes, which enable Mn-efficient plants to grow on marginal land with poor Mn availability....

  13. Manganese Research Health Project (MHRP)

    Science.gov (United States)

    2009-02-01

    green nucleic acid staining further confirmed the neurotoxic effect of cadmium in this cell model (Fig 10C). Next, we examined the enzymatic activity...Quantification of Nissl bodies revealed a widespread reduction in SNpc cell numbers. Other areas of the basal ganglia were also altered by manganese as...the substantia nigra pars compacta (SNpc) following manganese treatment. Quantification of Nissl bodies revealed a widespread reduction in SNpc

  14. Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Jodie [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom); Berntsen, Hanne Friis; Zimmer, Karin Elisabeth [Norwegian University of Life Sciences, Oslo (Norway); Frizzell, Caroline [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom); Verhaegen, Steven; Ropstad, Erik [Norwegian University of Life Sciences, Oslo (Norway); Connolly, Lisa, E-mail: l.connolly@qub.ac.uk [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom)

    2016-03-01

    Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds, chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p’-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2 h and 48 h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC + Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br + Cl, PFC + Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. - Highlights: • High content analysis (HCA) is a novel approach for determining toxicity of

  15. Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening

    International Nuclear Information System (INIS)

    Wilson, Jodie; Berntsen, Hanne Friis; Zimmer, Karin Elisabeth; Frizzell, Caroline; Verhaegen, Steven; Ropstad, Erik; Connolly, Lisa

    2016-01-01

    Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds, chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p’-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2 h and 48 h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC + Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br + Cl, PFC + Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. - Highlights: • High content analysis (HCA) is a novel approach for determining toxicity of

  16. The Level of Testosterone, Vitamin D, and Irregular Menstruation More Important than Omega-3 in Non-Symptomatic Women Will Define the Fate of Multiple Scleroses in Future.

    Science.gov (United States)

    Tavakol, Shima; Shakibapour, Sahar; Bidgoli, Sepideh Arbabi

    2018-01-01

    Multiple sclerosis is one of the most salient degenerative disorders of CNS with dysregulated immune process that resulted in axonal damage and demyelination. In the present investigation, the serum level of testosterone was assessed in women who were struggling with multiple sclerosis (MS). Also, the level of omega-3, vitamin D, and the irregular menstruation in women 5 years before the onset MS symptoms were surveyed. Although the levels of omega-3 and vitamin D in women MS patients were non-significant and significantly less than the healthy ones, they were significantly less in the whole population of MS patients. However, the MS patients more experienced more irregular menstruation some years before the onset of MS with the low level of testosterone. Based on the presented findings, it might be said that the vitamin D intake has significant protective role in women and men MS patients unlike the omega-3 that had significant protective role just in men. However, vitamin D metabolism encoding genes of CYP27B1 and CYP24A1 and predicting MS risk gene of HLA-DRB1*15:01 define its fate as well. Besides, vitamin D intake, through the proliferation decrement of pro-inflammatory cells, decreases of pro-inflammatory markers (IL-6, TNF-α, INF-γ) and auto-immune pathways have potential role in recovery of irregular menstruation in women with the low level of testosterone as a red warning factor of MS development. The low level of testosterone and vitamin D consumption increase the neural damage and pro-inflammatory pathways in MS patients, and the difference among the investigations is related to the long-standing history of MS that influences severity of damage to the neural cells and biomolecules and complicate its recovery.

  17. Defining conservation units in a stocking-induced genetic melting pot: unraveling native and multiple exotic genetic imprints of recent and historical secondary contact in Adriatic grayling.

    Science.gov (United States)

    Meraner, Andreas; Cornetti, Luca; Gandolfi, Andrea

    2014-04-01

    The definition of conservation units is crucial for the sustainable management of endangered species, though particularly challenging when recent and past anthropogenic and natural gene flow might have played a role. The conservation of the European grayling, Thymallus thymallus, is particularly complex in its southern distribution area, where the Adriatic evolutionary lineage is endangered by a long history of anthropogenic disturbance, intensive stocking and potentially widespread genetic introgression. We provide mtDNA sequence and microsatellite data of 683 grayling from 30 sites of Adriatic as well as Danubian and Atlantic origin. We apply Bayesian clustering and Approximate Bayesian Computation (ABC) to detect microgeographic population structure and to infer the demographic history of the Adriatic populations, to define appropriate conservation units. Varying frequencies of indigenous genetic signatures of the Adriatic grayling were revealed, spanning from marginal genetic introgression to the collapse of native gene pools. Genetic introgression involved multiple exotic source populations of Danubian and Atlantic origin, thus evidencing the negative impact of few decades of stocking. Within the Adige River system, a contact zone of western Adriatic and eastern Danubian populations was detected, with ABC analyses suggesting a historical anthropogenic origin of eastern Adige populations, most likely founded by medieval translocations. Substantial river-specific population substructure within the Adriatic grayling Evolutionary Significant Unit points to the definition of different conservation units. We finally propose a catalog of management measures, including the legal prohibition of stocking exotic grayling and the use of molecular markers in supportive- and captive-breeding programs.

  18. Extraction of manganese from electrolytic manganese residue by bioleaching.

    Science.gov (United States)

    Xin, Baoping; Chen, Bing; Duan, Ning; Zhou, Changbo

    2011-01-01

    Extraction of manganese from electrolytic manganese residues using bioleaching was investigated in this paper. The maximum extraction efficiency of Mn was 93% by sulfur-oxidizing bacteria at 4.0 g/l sulfur after bioleaching of 9days, while the maximum extraction efficiency of Mn was 81% by pyrite-leaching bacteria at 4.0 g/l pyrite. The series bioleaching first by sulfur-oxidizing bacteria and followed by pyrite-leaching bacteria evidently promoted the extraction of manganese, witnessing the maximum extraction efficiency of 98.1%. In the case of sulfur-oxidizing bacteria, the strong dissolution of bio-generated sulfuric acid resulted in extraction of soluble Mn2+, while both the Fe2+ catalyzed reduction of Mn4+ and weak acidic dissolution of Mn2+ accounted for the extraction of manganese with pyrite-leaching bacteria. The chemical simulation of bioleaching process further confirmed that the acid dissolution of Mn2+ and Fe2+ catalyzed reduction of Mn4+ were the bioleaching mechanisms involved for Mn extraction from electrolytic manganese residues. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. The scavenging of silver by manganese and iron oxides in stream sediments collected from two drainage areas of Colorado

    Science.gov (United States)

    Chao, T.T.; Anderson, B.J.

    1974-01-01

    Stream sediments of two well-weathered and aerated drainage areas of Colorado containing anomalous amounts of silver were allowed to react by shaking with nitric acid of different concentrations (1-10M). Silver, manganese, and iron simultaneously dissolved were determined by atomic absorption. The relationship between silver dissolution and the dissolution of manganese and/or iron was evaluated by linear and multiple regression analyses. The highly significant correlation coefficient (r = 0.913) between silver and manganese dissolution suggests that manganese oxides are the major control on the scavenging of silver in these stream sediments, whereas iron oxides only play a secondary role in this regard. ?? 1974.

  20. Determination of manganese content in aqueous solutions

    International Nuclear Information System (INIS)

    Reeder, S.D.; Smith, J.R.

    1977-01-01

    The three analytical methods used in the hydrogen-to-manganese cross-section ratio measurement were: volumetric determination of manganese, gravimetric analysis of manganous sulfate; and densimetric determination of manganous sulfate

  1. Manganese activated phosphate glass for dosimetry

    International Nuclear Information System (INIS)

    Regulla, D.

    1975-01-01

    A measuring element comprises a metaphosphate glass doped with manganese as an activator. The manganese activated metaphosphate glass can detect and determine radiation doses in the range between milliroentgens and more than 10 megaroentgens. (auth)

  2. Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys

    Directory of Open Access Journals (Sweden)

    Wong Brian A

    2005-10-01

    Full Text Available Abstract Background Neurotoxicity and pulmonary dysfunction are well-recognized problems associated with prolonged human exposure to high concentrations of airborne manganese. Surprisingly, histological characterization of pulmonary responses induced by manganese remains incomplete. The primary objective of this study was to characterize histologic changes in the monkey respiratory tract following manganese inhalation. Methods Subchronic (6 hr/day, 5 days/week inhalation exposure of young male rhesus monkeys to manganese sulfate was performed. One cohort of monkeys (n = 4–6 animals/exposure concentration was exposed to air or manganese sulfate at 0.06, 0.3, or 1.5 mg Mn/m3 for 65 exposure days. Another eight monkeys were exposed to manganese sulfate at 1.5 mg Mn/m3 for 65 exposure days and held for 45 or 90 days before evaluation. A second cohort (n = 4 monkeys per time point was exposed to manganese sulfate at 1.5 mg Mn/m3 and evaluated after 15 or 33 exposure days. Evaluations included measurement of lung manganese concentrations and evaluation of respiratory histologic changes. Tissue manganese concentrations were compared for the exposure and control groups by tests for homogeneity of variance, analysis of variance, followed by Dunnett's multiple comparison. Histopathological findings were evaluated using a Pearson's Chi-Square test. Results Animals exposed to manganese sulfate at ≥0.3 mg Mn/m3 for 65 days had increased lung manganese concentrations. Exposure to manganese sulfate at 1.5 mg Mn/m3 for ≥15 exposure days resulted in increased lung manganese concentrations, mild subacute bronchiolitis, alveolar duct inflammation, and proliferation of bronchus-associated lymphoid tissue. Bronchiolitis and alveolar duct inflammatory changes were absent 45 days post-exposure, suggesting that these lesions are reversible upon cessation of subchronic high-dose manganese exposure. Conclusion High-dose subchronic manganese sulfate inhalation is

  3. 21 CFR 184.1446 - Manganese chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Manganese chloride. 184.1446 Section 184.1446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Specific Substances Affirmed as GRAS § 184.1446 Manganese chloride. (a) Manganese chloride (MnCl2·4H2O, CAS...

  4. 21 CFR 582.5446 - Manganese chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  5. Dietary manganese in the Glasgow area

    International Nuclear Information System (INIS)

    Cross, J.D.; Dale, I.M.; Raie, R.M.

    1979-01-01

    The manganese content of the diet and human tissue (adult and infant) in the Glasgow area is established. The total manganese intake by a breast fed infant (6 μg/day) is very much lower than that of an adult (5 mg/day). This does not appear to cause any upset in the infant's metabolism and the tissue levels of both groups are similar. This indicates that the human system can obtain its required manganese from both levels of intake. Tea is the major source of manganese in the diet: tobacco, which is rich in manganese, does not contribute a significant amount when smoked. (author)

  6. Noncollinear magnetism in manganese nanostructures

    Czech Academy of Sciences Publication Activity Database

    Zelený, Martin; Šob, Mojmír; Hafner, J.

    2009-01-01

    Roč. 80, č. 14 (2009), 144414/1-144414/19 ISSN 1098-0121 R&D Projects: GA AV ČR IAA100100920; GA MŠk OC09011 Institutional research plan: CEZ:AV0Z20410507 Keywords : magnetism of nanostructures * nanowires * noncollinear magnetism * manganese Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.475, year: 2009

  7. Define Project

    DEFF Research Database (Denmark)

    Munk-Madsen, Andreas

    2005-01-01

    "Project" is a key concept in IS management. The word is frequently used in textbooks and standards. Yet we seldom find a precise definition of the concept. This paper discusses how to define the concept of a project. The proposed definition covers both heavily formalized projects and informally...... organized, agile projects. Based on the proposed definition popular existing definitions are discussed....

  8. "Dermatitis" defined.

    Science.gov (United States)

    Smith, Suzanne M; Nedorost, Susan T

    2010-01-01

    The term "dermatitis" can be defined narrowly or broadly, clinically or histologically. A common and costly condition, dermatitis is underresourced compared to other chronic skin conditions. The lack of a collectively understood definition of dermatitis and its subcategories could be the primary barrier. To investigate how dermatologists define the term "dermatitis" and determine if a consensus on the definition of this term and other related terms exists. A seven-question survey of dermatologists nationwide was conducted. Of respondents (n  =  122), half consider dermatitis to be any inflammation of the skin. Nearly half (47.5%) use the term interchangeably with "eczema." Virtually all (> 96%) endorse the subcategory "atopic" under the terms "dermatitis" and "eczema," but the subcategories "contact," "drug hypersensitivity," and "occupational" are more highly endorsed under the term "dermatitis" than under the term "eczema." Over half (55.7%) personally consider "dermatitis" to have a broad meaning, and even more (62.3%) believe that dermatologists as a whole define the term broadly. There is a lack of consensus among experts in defining dermatitis, eczema, and their related subcategories.

  9. Removal of Arsenic, Iron, Manganese, and Ammonia in Drinking Water: Nagaoka International Corporation CHEMILES NCL Series Water Treatment System

    Science.gov (United States)

    The Nagaoka International Corporation CHEMILES NCL Series system was tested to verify its performance for the reduction of multiple contaminants including: arsenic, ammonia, iron, and manganese. The objectives of this verification, as operated under the conditions at the test si...

  10. Spectroscopic characterization of manganese minerals.

    Science.gov (United States)

    Lakshmi Reddy, S; Padma Suvarna, K; Udayabhaska Reddy, G; Endo, Tamio; Frost, R L

    2014-01-03

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Relations between water physico-chemistry and benthic algal communities in a northern Canadian watershed: defining reference conditions using multiple descriptors of community structure.

    Science.gov (United States)

    Thomas, Kathryn E; Hall, Roland I; Scrimgeour, Garry J

    2015-09-01

    Defining reference conditions is central to identifying environmental effects of anthropogenic activities. Using a watershed approach, we quantified reference conditions for benthic algal communities and their relations to physico-chemical conditions in rivers in the South Nahanni River watershed, NWT, Canada, in 2008 and 2009. We also compared the ability of three descriptors that vary in terms of analytical costs to define algal community structure based on relative abundances of (i) all algal taxa, (ii) only diatom taxa, and (iii) photosynthetic pigments. Ordination analyses showed that variance in algal community structure was strongly related to gradients in environmental variables describing water physico-chemistry, stream habitats, and sub-watershed structure. Water physico-chemistry and local watershed-scale descriptors differed significantly between algal communities from sites in the Selwyn Mountain ecoregion compared to sites in the Nahanni-Hyland ecoregions. Distinct differences in algal community types between ecoregions were apparent irrespective of whether algal community structure was defined using all algal taxa, diatom taxa, or photosynthetic pigments. Two algal community types were highly predictable using environmental variables, a core consideration in the development of Reference Condition Approach (RCA) models. These results suggest that assessments of environmental impacts could be completed using RCA models for each ecoregion. We suggest that use of algal pigments, a high through-put analysis, is a promising alternative compared to more labor-intensive and costly taxonomic approaches for defining algal community structure.

  12. Defining chaos.

    Science.gov (United States)

    Hunt, Brian R; Ott, Edward

    2015-09-01

    In this paper, we propose, discuss, and illustrate a computationally feasible definition of chaos which can be applied very generally to situations that are commonly encountered, including attractors, repellers, and non-periodically forced systems. This definition is based on an entropy-like quantity, which we call "expansion entropy," and we define chaos as occurring when this quantity is positive. We relate and compare expansion entropy to the well-known concept of topological entropy to which it is equivalent under appropriate conditions. We also present example illustrations, discuss computational implementations, and point out issues arising from attempts at giving definitions of chaos that are not entropy-based.

  13. Mineral resource of the month: manganese

    Science.gov (United States)

    Corathers, Lisa A.

    2012-01-01

    Manganese is a silver-colored metal resembling iron and often found in conjunction with iron. The earliest-known human use of manganese compounds was in the Stone Age, when early humans used manganese dioxide as pigments in cave paintings. In ancient Rome and Egypt, people started using it to color or remove the color from glass - a practice that continued to modern times. Today, manganese is predominantly used in metallurgical applications as an alloying addition, particularly in steel and cast iron production. Steel and cast iron together provide the largest market for manganese (historically 85 to 90 percent), but it is also alloyed with nonferrous metals such as aluminum and copper. Its importance to steel cannot be overstated, as almost all types of steel contain manganese and could not exist without it.

  14. Multiple caeco-appendiceal fistulas and diverticulosis: a newly defined congenital anomaly of the appendix-report of the first case.

    Science.gov (United States)

    Yucel, Ahmet Fikret; Pergel, Ahmet; Kocakusak, Ahmet; Aydin, Ibrahim; Bagci, Pelin; Sahin, Dursun Ali

    2011-11-01

    Congenital anomalies of the appendix are extremely rare. They are usually found incidentally during operations other than appendectomies. Congenital appendix diverticula are even less frequent. Congenital caeco-appendiceal fistulae have not been reported until today. Herein, we present real diverticula of the appendix with multiple caeco-appendiceal fistulae which, to our knowledge, is the first in the literature.

  15. Defining Cyberbullying.

    Science.gov (United States)

    Englander, Elizabeth; Donnerstein, Edward; Kowalski, Robin; Lin, Carolyn A; Parti, Katalin

    2017-11-01

    Is cyberbullying essentially the same as bullying, or is it a qualitatively different activity? The lack of a consensual, nuanced definition has limited the field's ability to examine these issues. Evidence suggests that being a perpetrator of one is related to being a perpetrator of the other; furthermore, strong relationships can also be noted between being a victim of either type of attack. It also seems that both types of social cruelty have a psychological impact, although the effects of being cyberbullied may be worse than those of being bullied in a traditional sense (evidence here is by no means definitive). A complicating factor is that the 3 characteristics that define bullying (intent, repetition, and power imbalance) do not always translate well into digital behaviors. Qualities specific to digital environments often render cyberbullying and bullying different in circumstances, motivations, and outcomes. To make significant progress in addressing cyberbullying, certain key research questions need to be addressed. These are as follows: How can we define, distinguish between, and understand the nature of cyberbullying and other forms of digital conflict and cruelty, including online harassment and sexual harassment? Once we have a functional taxonomy of the different types of digital cruelty, what are the short- and long-term effects of exposure to or participation in these social behaviors? What are the idiosyncratic characteristics of digital communication that users can be taught? Finally, how can we apply this information to develop and evaluate effective prevention programs? Copyright © 2017 by the American Academy of Pediatrics.

  16. PubstractHelper: A Web-based Text-Mining Tool for Marking Sentences in Abstracts from PubMed Using Multiple User-Defined Keywords.

    Science.gov (United States)

    Chen, Chou-Cheng; Ho, Chung-Liang

    2014-01-01

    While a huge amount of information about biological literature can be obtained by searching the PubMed database, reading through all the titles and abstracts resulting from such a search for useful information is inefficient. Text mining makes it possible to increase this efficiency. Some websites use text mining to gather information from the PubMed database; however, they are database-oriented, using pre-defined search keywords while lacking a query interface for user-defined search inputs. We present the PubMed Abstract Reading Helper (PubstractHelper) website which combines text mining and reading assistance for an efficient PubMed search. PubstractHelper can accept a maximum of ten groups of keywords, within each group containing up to ten keywords. The principle behind the text-mining function of PubstractHelper is that keywords contained in the same sentence are likely to be related. PubstractHelper highlights sentences with co-occurring keywords in different colors. The user can download the PMID and the abstracts with color markings to be reviewed later. The PubstractHelper website can help users to identify relevant publications based on the presence of related keywords, which should be a handy tool for their research. http://bio.yungyun.com.tw/ATM/PubstractHelper.aspx and http://holab.med.ncku.edu.tw/ATM/PubstractHelper.aspx.

  17. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.

    Science.gov (United States)

    Suzuki, Teruhiko; Kazuki, Yasuhiro; Oshimura, Mitsuo; Hara, Takahiko

    2014-01-01

    Human artificial chromosomes (HACs) are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV) into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system) via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.

  18. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.

    Directory of Open Access Journals (Sweden)

    Teruhiko Suzuki

    Full Text Available Human artificial chromosomes (HACs are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.

  19. Alternative method of portable irradiation of manganese sulphate solution by an plutonium-beryllium source for manganese sulphate bath efficiency measurements

    International Nuclear Information System (INIS)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner

    2016-01-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO_4 solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  20. 10Be in manganese nodules

    International Nuclear Information System (INIS)

    Thomas, J.; Parker, P.; Mangini, A.; Cochran, K.; Turekian, K.; Krishnaswami, S.; Sharma, P.

    1981-01-01

    10 Be (t/sub 1/2) = 1.5 MY) is(formed in the upper atmosphere by cosmic ray spallation on nitrogen and oxygen. It is transported to the earth's surface via precipitation. In the oceans it is eventually associated with solid phases depositing on the ocean floor such as manganese nodules and deep-sea sediments. One of the assumptions that is normally made in analysis of such processes is that 10 Be has been produced at a relatively uniform rate over the pat several million years. If we assume, in addition, that the initial specific concentration of 10 Be as it precipitates with a solid phase is invariant with time, then we would expect that the decrease of the 10 Be concentration as a function of depth in a deep-sea core or in a manganese nodule would provide a record of sediment accumulation rate in the former and of growth rate in the latter. The possibility of using cosmic-ray produced 10 Be for the dating of marine deposits had been proposed 25 years ago by Arnold and Goel et al. The method of analysis used by these investigators, and those subsequently pursuing the problem, was low-level β counting. Though the potential of using 10 Be for dating manganese nodules was explored more than a decade ago, only a few measurements of 10 Be in nodules exist in date. This is largely because of the 10 Be measurements in environmental samples have gained considerable momentum during the past 3 to 4 years, after the development of accelerator mass spectrometry for its determination

  1. Evidence for polaron conduction in nanostructured manganese ferrite

    International Nuclear Information System (INIS)

    Gopalan, E Veena; Anantharaman, M R; Malini, K A; Saravanan, S; Kumar, D Sakthi; Yoshida, Yasuhiko

    2008-01-01

    Nanoparticles of manganese ferrite were prepared by the chemical co-precipitation technique. The dielectric parameters, namely, real and imaginary dielectric permittivity (ε' and ε-prime), ac conductivity (σ ac ) and dielectric loss tangent (tanδ), were measured in the frequency range of 100 kHz-8 MHz at different temperatures. The variations of dielectric dispersion (ε') and dielectric absorption (ε-prime) with frequency and temperature were also investigated. The variation of dielectric permittivity with frequency and temperature followed the Maxwell-Wagner model based on interfacial polarization in consonance with Koops phenomenological theory. The dielectric loss tangent and hence ε-prime exhibited a relaxation at certain frequencies and at relatively higher temperatures. The dispersion of dielectric permittivity and broadening of the dielectric absorption suggest the possibility of a distribution of relaxation time and the existence of multiple equilibrium states in manganese ferrite. The activation energy estimated from the dielectric relaxation is found to be high and is characteristic of polaron conduction in the nanosized manganese ferrite. The ac conductivity followed a power law dependence σ ac = Bω n typical of charge transport assisted by a hopping or tunnelling process. The observed minimum in the temperature dependence of the frequency exponent n strongly suggests that tunnelling of the large polarons is the dominant transport process

  2. Impact of initial FDG-PET/CT and serum-free light chain on transformation of conventionally defined solitary plasmacytoma to multiple myeloma.

    Science.gov (United States)

    Fouquet, Guillemette; Guidez, Stéphanie; Herbaux, Charles; Van de Wyngaert, Zoé; Bonnet, Sarah; Beauvais, David; Demarquette, Hélène; Adib, Salim; Hivert, Bénédicte; Wemeau, Mathieu; Berthon, Céline; Terriou, Louis; Coiteux, Valérie; Macro, Margaret; Decaux, Olivier; Facon, Thierry; Huglo, Damien; Leleu, Xavier

    2014-06-15

    Solitary plasmacytoma (SP) is a localized proliferation of monoclonal plasma cells in either bone or soft tissue, without evidence of multiple myeloma (MM), and whose prognosis is marked by a high risk of transformation to MM. We studied the impact of FDG-PET/CT (2[18F]fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography) on the risk of transformation of SP to overt MM among other markers in a series of 43 patients diagnosed with SP. Median age was 57.5 years; 48% of patients had an abnormal involved serum-free light chain (sFLC) value, and 64% had an abnormal sFLC ratio at diagnosis. Thirty-three percent had two or more hypermetabolic lesions on initial PET/CT, and 20% had two or more focal lesions on initial MRI. With a median follow-up of 50 months, 14 patients transformed to MM with a median time (TTMM) of 71 months. The risk factors that significantly shortened TTMM at diagnosis were two or more hypermetabolic lesions on PET/CT, abnormal sFLC ratio and involved sFLC, and to a lesser extent at completion of treatment, absence of normalized involved sFLC and PET/CT or MRI. In a multivariate analysis, abnormal initial involved sFLC [OR = 10; 95% confidence interval (CI), 1-87; P = 0.008] and PET/CT (OR = 5; 95% CI, 0-9; P = 0.032) independently shortened TTMM. An abnormal involved sFLC value and the presence of at least two hypermetabolic lesions on PET/CT at diagnosis of SP were the two predictors of early evolution to myeloma in our series. This data analysis will need confirmation in a larger study, and the study of these two risk factors may lead to a different management of patients with SP in the future. . ©2014 American Association for Cancer Research.

  3. An intermediate level of CD161 expression defines a novel activated, inflammatory, and pathogenic subset of CD8+ T cells involved in multiple sclerosis.

    Science.gov (United States)

    Nicol, Bryan; Salou, Marion; Vogel, Isabel; Garcia, Alexandra; Dugast, Emilie; Morille, Jeremy; Kilens, Stéphanie; Charpentier, Eric; Donnart, Audrey; Nedellec, Steven; Jacq-Foucher, Marylène; Le Frère, Fabienne; Wiertlewski, Sandrine; Bourreille, Arnaud; Brouard, Sophie; Michel, Laure; David, Laurent; Gourraud, Pierre-Antoine; Degauque, Nicolas; Nicot, Arnaud B; Berthelot, Laureline; Laplaud, David-Axel

    2018-03-01

    Several lines of evidence support a key role for CD8 + T cells in central nervous system tissue damage of patients with multiple sclerosis. However, the precise phenotype of the circulating CD8 + T cells that may be recruited from the peripheral blood to invade the CNS remains largely undefined to date. It has been suggested that IL-17 secreting CD8 (Tc17) T cells may be involved, and in humans these cells are characterized by the expression of CD161. We focused our study on a unique and recently described subset of CD8 T cells characterized by an intermediate expression of CD161 as its role in neuroinflammation has not been investigated to date. The frequency, phenotype, and function of CD8 + T cells with an intermediate CD161 expression level were characterized ex-vivo, in vitro, and in situ using RNAseq, RT-PCR, flow cytometry, TCR sequencing, and immunohistofluorescence of cells derived from healthy volunteers (n = 61), MS subjects (n = 90), as well as inflammatory (n = 15) and non-inflammatory controls (n = 6). We report here that CD8 + CD161 int T cells present characteristics of effector cells, up-regulate cell-adhesion molecules and have an increased ability to cross the blood-brain barrier and to secrete IL-17, IFNγ, GM-CSF, and IL-22. We further demonstrate that these cells are recruited and enriched in the CNS of MS subjects where they produce IL-17. In the peripheral blood, RNAseq, RT-PCR, high-throughput TCR repertoire analyses, and flow cytometry confirmed an increased effector and transmigration pattern of these cells in MS patients, with the presence of supernumerary clones compared to healthy controls. Our data demonstrate that intermediate levels of CD161 expression identifies activated and effector CD8 + T cells with pathogenic properties that are recruited to MS lesions. This suggests that CD161 may represent a biomarker and a valid target for the treatment of neuroinflammation. Copyright © 2017 The Authors. Published by Elsevier Ltd

  4. Cycle aging studies of lithium nickel manganese cobalt oxide-based batteries using electrochemical impedance spectroscopy

    NARCIS (Netherlands)

    Maheshwari, Arpit; Heck, Michael; Santarelli, Massimo

    2018-01-01

    The cycle aging of a commercial 18650 lithium-ion battery with graphite anode and lithium nickel manganese cobalt (NMC) oxide-based cathode at defined operating conditions is studied by regular electrochemical characterization, electrochemical impedance spectroscopy (EIS) and post-mortem analysis.

  5. Recovery of manganese from manganese oxide ores in the EDTA solution

    Science.gov (United States)

    Zhang, Chao; Wang, Shuai; Cao, Zhan-fang; Zhong, Hong

    2018-04-01

    A new process has been experimentally and theoretically established for the recovery of manganese from manganese oxide ores, mainly including the reductive leaching of manganese by ethylenediaminetetraacetic acid (EDTA), EDTA recovery, and manganese electrolysis. The experimental conditions for this process were investigated. Moderate leaching environment by EDTA with the pH in the range of 5-6 is of benefit to leach manganese from some manganese oxide ores with high-content impurities, such as iron and aluminum. Most of EDTA can be recovered by acidification. A small amount of the residual EDTA in the electrolyte can prevent the generation of anode mud. In addition, trimanganese tetroxide (Mn3O4) can be obtained by the roasting of the EDTA-Mn crystallized product.

  6. Habit modification of nearly perfect single crystals of potassium dihydrogen phosphate (KDP) by trivalent manganese ions studied using synchrotron radiation X-ray multiple diffraction in Renninger scanning mode

    OpenAIRE

    Lai, X; Roberts, KJ; Avanci, LH; Cardoso, LP; Sasaki, JM

    2003-01-01

    The X-ray multiple diffraction technique using synchrotron radiation is applied in the preliminary study of the habit modification of KDP samples as induced by incorporation of the trivalent transition metal cation Mn3+. High-resolution Renninger scans of pure and doped KDP were carried out using 400 as the primary reflection, echoing the fact that these impurity species were segregated in the {100} growth sector. The analysis of the Renninger scans of the doped KDP crystals is consistent wit...

  7. Manganese oxide nanoparticles, methods and applications

    Science.gov (United States)

    Abruna, Hector D.; Gao, Jie; Lowe, Michael A.

    2017-08-29

    Manganese oxide nanoparticles having a chemical composition that includes Mn.sub.3O.sub.4, a sponge like morphology and a particle size from about 65 to about 95 nanometers may be formed by calcining a manganese hydroxide material at a temperature from about 200 to about 400 degrees centigrade for a time period from about 1 to about 20 hours in an oxygen containing environment. The particular manganese oxide nanoparticles with the foregoing physical features may be used within a battery component, and in particular an anode within a lithium battery to provide enhanced performance.

  8. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria

    OpenAIRE

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-01-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the p...

  9. Manganese Oxidation by Bacteria: Biogeochemical Aspects

    Digital Repository Service at National Institute of Oceanography (India)

    Sujith, P.P.; LokaBharathi, P.A.

    Manganese is an essential trace metal that is not as readily oxidizable like iron. Several bacterial groups posses the ability to oxidize Mn effectively competing with chemical oxidation. The oxides of Mn are the strongest of the oxidants, next...

  10. Manganese(II) chelate contrast media

    International Nuclear Information System (INIS)

    Rocklage, S.M.; Quay, S.C.

    1994-01-01

    New chelate forming compounds for use as contrast media in NMR imaging are described. Especially mentioned are manganese(II) ion chelates of N,N' dipyridoxaldiamine, N,N' diacetic acid, and salts and esters thereof. 1 fig

  11. 21 CFR 73.2775 - Manganese violet.

    Science.gov (United States)

    2010-04-01

    .... Mercury (as Hg), not more than 1 part per million. Total color, based on Mn content in “as is” sample, not less than 93 percent. (c) Uses and restrictions. Manganese violet is safe for use in coloring cosmetics...

  12. Personality traits in persons with manganese poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, A A

    1976-10-01

    Results of studies with the Minnesota Multiphasic Personality Inventory (MMPI) in 3 groups of arc welders with various degrees of manganese poisoning (22 symptom-free, 23 with functional disturbances, 55 with organic symptoms) and 50 controls were discussed. There was a close relation between the severity of the poisoning and quantitative and qualitative personality changes. Personality tests are considered a useful addition to the clinical diagnosis of chronic manganese poisoning.

  13. Autonomic function in manganese alloy workers

    Energy Technology Data Exchange (ETDEWEB)

    Barrington, W.W.; Angle, C.R.; Willcockson, N.K.; Padula, M.A. [Univ. of Nebraska Medical Center, Omaha, NE (United States); Korn, T.

    1998-07-01

    The observation of orthostatic hypotension in an index case of manganese toxicity lead to this prospective attempt to evaluate cardiovascular autonomic function and cognitive and emotional neurotoxicity in eight manganese alloy welders and machinists. The subjects consisted of a convenience sample consisting of an index case of manganese dementia, his four co-workers in a frog shop for gouging, welding, and grinding repair of high manganese railway track and a convenience sample of three mild steel welders with lesser manganese exposure also referred because of cognitive or autonomic symptoms. Frog shop air manganese samples 9.6--10 years before and 1.2--3.4 years after the diagnosis of the index case exceeded 1.0 mg/m{sup 3} in 29% and 0.2 mg/m{sup 3} in 62%. Twenty-four-hour electrocardiographic (Holter) monitoring was used to determine the temporal variability of the heartrate (RR{prime} interval) and the rates of change at low frequency and high frequency. MMPI and MCMI personality assessment and short-term memory, figure copy, controlled oral word association, and symbol digit tests were used.

  14. Magnesium and manganese content of halophilic bacteria

    International Nuclear Information System (INIS)

    de Medicis, E.; Paquette, J.; Gauthier, J.J.; Shapcott, D.

    1986-01-01

    Magnesium and manganese contents were measured by atomic absorption spectrophotometry in bacteria of several halophilic levels, in Vibrio costicola, a moderately halophilic eubacterium growing in 1 M NaCl, Halobacterium volcanii, a halophilic archaebacterium growing in 2.5 NaCl, Halobacterium cutirubrum, an extremely halophilic archaebacterium growing in 4 M NaCl, and Escherichia coli, a nonhalophilic eubacterium growing in 0.17 M NaCl. Magnesium and manganese contents varied with the growth phase, being maximal at the early log phase. Magnesium and manganese molalities in cell water were shown to increase with the halophilic character of the logarithmically growing bacteria, from 30 mmol of Mg per kg of cell water and 0.37 mmol of Mn per kg of cell water for E. coli to 102 mmol of Mg per kg of cell water and 1.6 mmol of Mn per kg of cell water for H cutirubrum. The intracellular concentrations of manganese were determined independently by a radioactive tracer technique in V. costicola and H. volcanii. The values obtained by 54 Mn loading represented about 70% of the values obtained by atomic absorption. The increase of magnesium and manganese contents associated with the halophilic character of the bacteria suggests that manganese and magnesium play a role in haloadaptation

  15. Defining depth of anesthesia.

    Science.gov (United States)

    Shafer, S L; Stanski, D R

    2008-01-01

    In this chapter, drawn largely from the synthesis of material that we first presented in the sixth edition of Miller's Anesthesia, Chap 31 (Stanski and Shafer 2005; used by permission of the publisher), we have defined anesthetic depth as the probability of non-response to stimulation, calibrated against the strength of the stimulus, the difficulty of suppressing the response, and the drug-induced probability of non-responsiveness at defined effect site concentrations. This definition requires measurement of multiple different stimuli and responses at well-defined drug concentrations. There is no one stimulus and response measurement that will capture depth of anesthesia in a clinically or scientifically meaningful manner. The "clinical art" of anesthesia requires calibration of these observations of stimuli and responses (verbal responses, movement, tachycardia) against the dose and concentration of anesthetic drugs used to reduce the probability of response, constantly adjusting the administered dose to achieve the desired anesthetic depth. In our definition of "depth of anesthesia" we define the need for two components to create the anesthetic state: hypnosis created with drugs such as propofol or the inhalational anesthetics and analgesia created with the opioids or nitrous oxide. We demonstrate the scientific evidence that profound degrees of hypnosis in the absence of analgesia will not prevent the hemodynamic responses to profoundly noxious stimuli. Also, profound degrees of analgesia do not guarantee unconsciousness. However, the combination of hypnosis and analgesia suppresses hemodynamic response to noxious stimuli and guarantees unconsciousness.

  16. Leaching of manganese from electrolytic manganese residue by electro-reduction.

    Science.gov (United States)

    Shu, Jiancheng; Liu, Renlong; Liu, Zuohua; Chen, Hongliang; Tao, Changyuan

    2017-08-01

    In this study, an improved process for leaching manganese from electrolytic manganese residue (EMR) by electro-reduction was developed. The mechanisms of the electro-reduction leaching were investigated through X-ray diffraction, scanning electron microscopy, X-ray fluorescence, and Brunauer Emmett Teller. The results show that the electric field could change the surface charge distribution of EMR particles, and the high-valent manganese can be reduced by electric field. The leaching efficient of manganese reached 84.1% under the optimal leaching condition: 9.2 wt% H 2 SO 4 , current density of 25 mA/cm 2 , solid-to-liquid ratio of 1:5, and leaching time for 1 h. It is 37.9% higher than that attained without an electric field. Meanwhile, the manganese content in EMR decreased from 2.57% to 0.48%.

  17. Effect of manganese on neonatal rat: manganese concentration and enzymatic alterations in brain

    Energy Technology Data Exchange (ETDEWEB)

    Seth, P K; Husain, R; Mushtaq, M; Chandra, S V

    1977-01-01

    Suckling rats were exposed for 15 and 30 days to manganese through the milk of nursing dams receiving 15 mg MnCl/sub 2/.4H/sub 2/O/kg/day orally and after which the neurological manifestations of metal poisoning were studied. No significant differences in the growth rate, developmental landmarks and walking movements were observed between the control and manganese-exposed pups. The metal concentration was significantly increased in the brain of manganese-fed pups at 15 days and exhibited a further three-fold increase over the control, at 30 days. The accumulation of the metal in the brain of manganese-exposed nursing dams was comparatively much less. A significant decrease in succinic dehydrogenase, adenosine triphosphatase, adenosine deaminase, acetylcholine esterase and an increase in monoamine oxidase activity was observed in the brain of experimental pups and dams. The results suggest that the developing brain may also be susceptible to manganese.

  18. Old age and gender influence the pharmacokinetics of inhaled manganese sulfate and manganese phosphate in rats

    International Nuclear Information System (INIS)

    Dorman, David C.; McManus, Brian E.; Marshall, Marianne W.; James, R. Arden; Struve, Melanie F.

    2004-01-01

    In this study, we examined whether gender or age influences the pharmacokinetics of manganese sulfate (MnSO 4 ) or manganese phosphate (as the mineral form hureaulite). Young male and female rats and aged male rats (16 months old) were exposed 6 h day -1 for 5 days week -1 to air, MnSO 4 (at 0.01, 0.1, or 0.5 mg Mn m -3 ), or hureaulite (0.1 mg Mn m -3 ). Tissue manganese concentrations were determined in all groups at the end of the 90-day exposure and 45 days later. Tissue manganese concentrations were also determined in young male rats following 32 exposure days and 91 days after the 90-day exposure. Intravenous 54 Mn tracer studies were also performed in all groups immediately after the 90-day inhalation to assess whole-body manganese clearance rates. Gender and age did not affect manganese delivery to the striatum, a known target site for neurotoxicity in humans, but did influence manganese concentrations in other tissues. End-of-exposure olfactory bulb, lung, and blood manganese concentrations were higher in young male rats than in female or aged male rats and may reflect a portal-of-entry effect. Old male rats had higher testis but lower pancreas manganese concentrations when compared with young males. Young male and female rats exposed to MnSO 4 at 0.5 mg Mn m -3 had increased 54 Mn clearance rates when compared with air-exposed controls, while senescent males did not develop higher 54 Mn clearance rates. Data from this study should prove useful in developing dosimetry models for manganese that consider age or gender as potential sensitivity factors

  19. Globally sustainable manganese metal production and use.

    Science.gov (United States)

    Hagelstein, Karen

    2009-09-01

    The "cradle to grave" concept of managing chemicals and wastes has been a descriptive analogy of proper environmental stewardship since the 1970s. The concept incorporates environmentally sustainable product choices-such as metal alloys utilized steel products which civilization is dependent upon. Manganese consumption is related to the increasing production of raw steel and upgrading ferroalloys. Nonferrous applications of manganese include production of dry-cell batteries, plant fertilizer components, animal feed and colorant for bricks. The manganese ore (high grade 35% manganese) production world wide is about 6 million ton/year and electrolytic manganese metal demand is about 0.7 million ton/year. The total manganese demand is consumed globally by industries including construction (23%), machinery (14%), and transportation (11%). Manganese is recycled within scrap of iron and steel, a small amount is recycled within aluminum used beverage cans. Recycling rate is 37% and efficiency is estimated as 53% [Roskill Metals and Minerals Reports, January 13, 2005. Manganese Report: rapid rise in output caused by Chinese crude steel production. Available from: http://www.roskill.com/reports/manganese.]. Environmentally sustainable management choices include identifying raw material chemistry, utilizing clean production processes, minimizing waste generation, recycling materials, controlling occupational exposures, and collecting representative environmental data. This paper will discuss two electrolytically produced manganese metals, the metal production differences, and environmental impacts cited to date. The two electrolytic manganese processes differ due to the addition of sulfur dioxide or selenium dioxide. Adverse environmental impacts due to use of selenium dioxide methodology include increased water consumption and order of magnitude greater solid waste generation per ton of metal processed. The use of high grade manganese ores in the electrolytic process also

  20. Photogeochemical reactions of manganese under anoxic conditions

    Science.gov (United States)

    Liu, W.; Yee, N.; Piotrowiak, P.; Falkowski, P. G.

    2017-12-01

    Photogeochemistry describes reactions involving light and naturally occurring chemical species. These reactions often involve a photo-induced electron transfer that does not occur in the absence of light. Although photogeochemical reactions have been known for decades, they are often ignored in geochemical models. In particular, reactions caused by UV radiation during an ozone free early Earth could have influenced the available oxidation states of manganese. Manganese is one of the most abundant transition metals in the crust and is important in both biology and geology. For example, the presence of manganese (VI) oxides in the geologic record has been used as a proxy for oxygenic photosynthesis; however, we suggest that the high oxidation state of Mn can be produced abiotically by photochemical reactions. Aqueous solutions of manganese (II) as well as suspensions of rhodochrosite (MnCO3) were irradiated under anoxic condition using a 450 W mercury lamp and custom built quartz reaction vessels. The photoreaction of the homogeneous solution of Mn(II) produced H2 gas and akhtenskite (ɛ-MnO2) as the solid product . This product is different than the previously identified birnessite. The irradiation of rhodochrosite suspensions also produced H2 gas and resulted in both a spectral shift as well as morphology changes of the mineral particles in the SEM images. These reactions offer alternative, abiotic pathways for the formation of manganese oxides.

  1. Manganese and acute paranoid psychosis: a case report

    NARCIS (Netherlands)

    Verhoeven, W.M.A.; Egger, J.I.M.; Kuijpers, H.J.H.

    2011-01-01

    Introduction Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional instability. Later,

  2. Manganese and acute paranoid psychosis: A case report

    NARCIS (Netherlands)

    W.M.A. Verhoeven (Wim); J.I.M. Egger (Jos); H.J. Kuijpers (Harold)

    2011-01-01

    textabstractIntroduction: Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional

  3. Silver manganese oxide electrodes for lithium batteries

    Science.gov (United States)

    Thackeray, Michael M.; Vaughey, John T.; Dees, Dennis W.

    2006-05-09

    This invention relates to electrodes for non-aqueous lithium cells and batteries with silver manganese oxide positive electrodes, denoted AgxMnOy, in which x and y are such that the manganese ions in the charged or partially charged electrodes cells have an average oxidation state greater than 3.5. The silver manganese oxide electrodes optionally contain silver powder and/or silver foil to assist in current collection at the electrodes and to improve the power capability of the cells or batteries. The invention relates also to a method for preparing AgxMnOy electrodes by decomposition of a permanganate salt, such as AgMnO4, or by the decomposition of KMnO4 or LiMnO4 in the presence of a silver salt.

  4. Manganese (II) induces chemical hypoxia by inhibiting HIF-prolyl hydroxylase: Implication in manganese-induced pulmonary inflammation

    International Nuclear Information System (INIS)

    Han, Jeongoh; Lee, Jong-Suk; Choi, Daekyu; Lee, Youna; Hong, Sungchae; Choi, Jungyun; Han, Songyi; Ko, Yujin; Kim, Jung-Ae; Mi Kim, Young; Jung, Yunjin

    2009-01-01

    Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1α protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1α hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1α degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1α protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines. The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation

  5. Manganese exposure in foundry furnacemen and scrap recycling workers

    DEFF Research Database (Denmark)

    Lander, F; Kristiansen, J; Lauritsen, Jens

    1999-01-01

    Cast iron products are alloyed with small quantities of manganese, and foundry furnacemen are potentially exposed to manganese during tapping and handling of smelts. Manganese is a neurotoxic substance that accumulates in the central nervous system, where it may cause a neurological disorder...

  6. Manganese phospate physical chemistry and surface properties

    International Nuclear Information System (INIS)

    Najera R, N.; Romero G, E. T.

    2008-01-01

    This paper presents the methodology for the manganese phosphate (III) synthesis (MnP0 4 H 2 0) from manganese chloride. The physicochemical characterization was carried out by: X-ray diffraction, scanning electron microscopy, infrared analysis and thermal gravimetric analysis. The surface characterization is obtained through the determination of surface area, point of zero charge and kinetics of moisture. As a phosphate compound of a metal with low oxidation state is a promising compound for removal pollutants from water and soil, can be used for the potential construction of containment barriers for radioactive wastes. (Author)

  7. Effect of manganese on neonatal rat: manganese distribution in vital organs

    Energy Technology Data Exchange (ETDEWEB)

    Husain, R; Mushtaq, M; Seth, P K; Chandra, S V

    1976-01-01

    At present very little is known about the effect of manganese on the early stage of life, though the metal poisoning in adult humans and experimental animals has been known for quite some time. The possibility of the exposure of the general public to the deleterious effects of the metal through the environmental contamination resulting from its increasing industrial applications, and the use of Methyl Cyclopentadienyl Manganese Tricarbonyl (MMT) in gasoline and motor fuel, points to the need for such an information. Our recent studies in this direction have shown that manganese exposed nursing dams can transfer significant amounts of the metal via maternal milk of their sucklings and the brain of the latter exhibited marked enzymatic alterations. The present communication deals with the distribution of manganese in the vital organs of rat pups nursing on mothers receiving the metal orally.

  8. Thermodynamic Properties of Manganese and Molybdenum

    International Nuclear Information System (INIS)

    Desai, P.D.

    1987-01-01

    This work reviews and discusses the data on the various thermodynamic properties of manganese and molybdenum available through March 1985. These include heat capacity, enthalpy, enthalpy of transitions and melting, vapor pressure, and enthalpy of vaporization. The existing data have been critically evaluated and analyzed. The recommended values for the heat capacity, enthalpy, entropy, and Gibbs energy function from 0.5 to 2400 K for manganese and from 0.4 to 5000 K for molybdenum have been generated, as have heat capacity values for supercooled β-Mn and for γ-Mn below 298.15 K. The recommended values for vapor pressure cover the temperature range from 298.15 to 2400 K for manganese and from 298.15 to 5000 K for molybdenum. These values are referred to temperatures based on IPTS-1968. The uncertainties in the recommended values of the heat capacity range from +-3% to +-5% for manganese and from +-1.5% to +-3% for molybdenum

  9. Iron and manganese deposits in Uruguay

    International Nuclear Information System (INIS)

    Alvarado, B.

    1959-01-01

    This report is the results of the study carried out for the United Nations expert which the main object was: the study of the information available about iron and manganese formation in Uruguay, as well as the main researching deposit to determinate economical possibilities in the exportation.

  10. Crystallization and spectroscopic studies of manganese malonate

    Indian Academy of Sciences (India)

    Administrator

    ... and its esters are important intermediates in syntheses of vitamins B1 and B6, barbitu- ... been a subject of interest because of the importance of such interactions in a ... The d-values of the Bragg peaks in the XRD. Figure 1. (a) Manganese ...

  11. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Changbo; Wang, Jiwei [Chinese Research Academy of Environmental Sciences, Beijing (China); Wang, Nanfang [Hunan Institute of Engineering, Xiangtan (China)

    2013-11-15

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  12. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    International Nuclear Information System (INIS)

    Zhou, Changbo; Wang, Jiwei; Wang, Nanfang

    2013-01-01

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn"2"+ solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn"2"+ solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  13. Soil manganese enrichment from industrial inputs: a gastropod perspective.

    Directory of Open Access Journals (Sweden)

    Despina-Maria Bordean

    Full Text Available Manganese is one of the most abundant metal in natural environments and serves as an essential microelement for all living systems. However, the enrichment of soil with manganese resulting from industrial inputs may threaten terrestrial ecosystems. Several studies have demonstrated harmful effects of manganese exposure by cutaneous contact and/or by soil ingestion to a wide range of soil invertebrates. The link between soil manganese and land snails has never been made although these invertebrates routinely come in contact with the upper soil horizons through cutaneous contact, egg-laying, and feeding activities in soil. Therefore, we have investigated the direct transfer of manganese from soils to snails and assessed its toxicity at background concentrations in the soil. Juvenile Cantareus aspersus snails were caged under semi-field conditions and exposed first, for a period of 30 days, to a series of soil manganese concentrations, and then, for a second period of 30 days, to soils with higher manganese concentrations. Manganese levels were measured in the snail hepatopancreas, foot, and shell. The snail survival and shell growth were used to assess the lethal and sublethal effects of manganese exposure. The transfer of manganese from soil to snails occurred independently of food ingestion, but had no consistent effect on either the snail survival or shell growth. The hepatopancreas was the best biomarker of manganese exposure, whereas the shell did not serve as a long-term sink for this metal. The kinetics of manganese retention in the hepatopancreas of snails previously exposed to manganese-spiked soils was significantly influenced by a new exposure event. The results of this study reveal the importance of land snails for manganese cycling in terrestrial biotopes and suggest that the direct transfer from soils to snails should be considered when precisely assessing the impact of anthropogenic Mn releases on soil ecosystems.

  14. QSAR analysis for nano-sized layered manganese-calcium oxide in water oxidation: An application of chemometric methods in artificial photosynthesis.

    Science.gov (United States)

    Shahbazy, Mohammad; Kompany-Zareh, Mohsen; Najafpour, Mohammad Mahdi

    2015-11-01

    Water oxidation is among the most important reactions in artificial photosynthesis, and nano-sized layered manganese-calcium oxides are efficient catalysts toward this reaction. Herein, a quantitative structure-activity relationship (QSAR) model was constructed to predict the catalytic activities of twenty manganese-calcium oxides toward water oxidation using multiple linear regression (MLR) and genetic algorithm (GA) for multivariate calibration and feature selection, respectively. Although there are eight controlled parameters during synthesizing of the desired catalysts including ripening time, temperature, manganese content, calcium content, potassium content, the ratio of calcium:manganese, the average manganese oxidation state and the surface of catalyst, by using GA only three of them (potassium content, the ratio of calcium:manganese and the average manganese oxidation state) were selected as the most effective parameters on catalytic activities of these compounds. The model's accuracy criteria such as R(2)test and Q(2)test in order to predict catalytic rate for external test set experiments; were equal to 0.941 and 0.906, respectively. Therefore, model reveals acceptable capability to anticipate the catalytic activity. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A simple route to synthesize manganese germanate nanorods

    International Nuclear Information System (INIS)

    Pei, L.Z.; Yang, Y.; Yuan, C.Z.; Duan Taike; Zhang Qianfeng

    2011-01-01

    Manganese germanate nanorods have been synthesized by a simple route using germanium dioxide and manganese acetate as the source materials. X-ray diffraction observation shows that the nanorods are composed of orthorhombic and monoclinic manganese germanate phases. Scanning electron microscopy and transmission electron microscopy observations display that the manganese germanate nanorods have flat tips with the length of longer than 10 micrometers and diameter of 60-350 nm, respectively. The role of the growth conditions on the formation of the manganese germanate nanorods shows that the proper selection and combination of the growth conditions are the key factor for controlling the formation of the manganese germanate nanorods. The photoluminescence spectrum of the manganese germanate nanorods exhibits four fluorescence emission peaks centered at 422 nm, 472 nm, 487 nm and 530 nm showing the application potential for the optical devices. - Research Highlights: → Manganese germanate nanorods have been synthesized by simple hydrothermal process. → The formation of manganese germanate nanorods can be controlled by growth conditions. → Manganese germanate nanorods exhibit good PL emission ability for optical device.

  16. Manganese binding proteins in human and cow's milk

    International Nuclear Information System (INIS)

    Loennerdal, B.; Keen, C.L.; Hurley, L.S.

    1985-01-01

    Manganese nutrition in the neonatal period is poorly understood, due in part to a lack of information on the amount of manganese in infant foods and its bioavailability. Since the molecular localization of an element in foods is one determinant of its subsequent bioavailability, a study was made of the binding of manganese in human and cow's milk. An extrinsic label of 54 Mn was shown to equilibrate isotopically with native manganese in milks and formulas. Milk samples were separated into fat, casein and whey by ultracentrifugation. In human milk, the major part (71%) of manganese was found in whey, 11% in casein and 18% in the lipid fraction. In contrast, in cow's milk, 32% of total manganese was in whey, 67% in casein and 1% in lipid. Within the human whey fraction, most of the manganese was bound to lactoferrin, while in cow's whey, manganese was mostly complexed to ligands with molecular weights less than 200. The distribution of manganese in formulas was closer to that of human milk than of cow's milk. The bioavailability of manganese associated with lactoferrin, casein and low molecular weight complexes needs to be assessed

  17. Characterization of Sumbawa manganese ore and recovery of manganese sulfate as leaching products

    Science.gov (United States)

    Kusumaningrum, Retno; Rahmani, Siti Astari; Widayatno, Wahyu Bambang; Wismogroho, Agus Sukarto; Nugroho, Dwi Wahyu; Maulana, Syahrizal; Rochman, Nurul Taufiqu; Amal, M. Ikhlasul

    2018-05-01

    The aims of this research were to study the leaching process of manganese ore which originated from Sumbawa, Indonesia and its characterization. A high grade Indonesian manganese ore from Sumbawa, West of Nusa Tenggara was characterized by X-Ray Fluorescence (XRF). The result showed composition of 78.8 % Mn, 17.77% Fe and the rest were trace elements such as Si, Co, Ti, Zn, V and Zr contents. X-Ray Diffraction analysis showed that the manganese ore was consisted of pyrolusite (MnO2), rhodonite (MnSiO3), rhodochrosite (MnCO3) and hematite (Fe2O3). Manganese ore was also analyzed by thermal analysis to observe their thermal decomposition character. In this study, sulphuric acid (H2SO4, 6 M) was deployed as leaching agent. The leaching process was performed at 90 °C for two hours with the addition of NH4OH to control pH. Recovery percentage of leaching process yielded of 87 % Mn extracted. The crystallization process result at heating temperature of 200 °C was confirmed by XRD as manganese sulfate.

  18. Hydrometallurgical Process and Kinetics of Leaching Manganese from Semi-Oxidized Manganese Ores with Sucrose

    Directory of Open Access Journals (Sweden)

    Yuhong Wang

    2017-02-01

    Full Text Available The extraction of manganese from a semi-oxidized manganese ore was investigated with sucrose as the reducing agent in dilute sulfuric acid medium. The kinetics of leaching manganese from the complex ore containing MnCO3 and MnO2 was also investigated. The effects of sucrose and sulfuric acid concentrations, leaching temperature and reaction time on the total Mn (TMn, MnO2 and MnCO3 leaching were investigated. Results showed that MnCO3 could more easily react with hydrogen ions than MnO2 in ores, and MnO2 decomposition could be advantageous for MnCO3 leaching. The leaching efficiencies of 91.8% for total Mn, 91.4% for MnO2 and 96.9% for MnCO3 were obtained under the following optimized conditions: 0.035 mol/L sucrose concentration, 5 mol/L sulfuric acid concentration, 60 min of reaction time and 363.2 K of leaching temperature. In addition, it was found that the leaching process of semi-oxidized manganese ore follows the shrinking core model and the leaching rate was controlled by chemical reaction and diffusion. The apparent activation energy of the total manganese, MnO2, and MnCO3 leaching were 40.83, 40.59, and 53.33 kJ·mol−1, respectively.

  19. Bioleaching of a manganese and silver Ore

    International Nuclear Information System (INIS)

    Porro, S.; Tedesco, P.H.; La Plata

    1990-01-01

    The bioleaching with a strain of Thiobacillus thiooxidans of the ore of Farallon Negro (Catamarca, Argentina) was studied in order to estimate its application to the solution and recovery of the manganese, and to improve the silver extraction. The State company which works the mine has not yet found an economical process to extract the manganese and has only reached a 30% efficiency in the recovery of silver by cianuration. The effects of pulp density variations and the addition of different quantities of FeS were analysed looking for the best working conditions. 74 μm (mesh Tyler 200) of ore particles were used because that is the size used in this plant for the cianuration process. (Author)

  20. Arsenic removal by manganese greensand filters

    Energy Technology Data Exchange (ETDEWEB)

    Phommavong, T. [Saskatchewan Environment, Regina (Canada); Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

    1994-12-31

    Some of the small communities in Saskatchewan are expected to have difficulty complying with the new maximum acceptable concentration (MAC) of 25 {micro}g/L for arsenic. A test column was set up in the laboratory to study the removal of arsenic from the potable water using oxidation with KMnO{sub 4}, followed by manganese greensand filtration. Tests were run using water from the tap having a background arsenic concentration of <0.5 {micro}g/L and iron concentration in the range of 0.02 to 0.77 mg/L. The test water was spiked with arsenic and iron. Results showed that 61 % to 98% of arsenic can be removed from the potable water by oxidation with KMnO{sub 4} followed by manganese greensand filtration.

  1. Iron and manganese removal from drinking water

    OpenAIRE

    Pascu, Daniela-Elena; Neagu (Pascu), Mihaela; Alina Traistaru, Gina; Nechifor, Aurelia Cristina; Raluca Miron, Alexandra

    2016-01-01

    The purpose of the present study is to find a suitable method for removal of iron and manganese from ground water, considering both local economical and environmental aspects. Ground water is a highly important source of drinking water in Romania. Ground water is naturally pure from bacteria at a 25 m depth or more. However, solved metals may occur and if the levels are too high, the water is not drinkable. Different processes, such as electrochemical and combined electrochemical-adsorption m...

  2. Manganese concentration in human saliva using NAA

    Energy Technology Data Exchange (ETDEWEB)

    Lewgoy, Hugo R., E-mail: hugorl@usp.br [Universidade Bandeirante Anhanguera (UNIBAN), Sao Paulo, SP (Brazil); Zamboni, Cibele B.; Medeiros, Ilca M.M.A.; Medeiros, Jose A.G. de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    In this investigation the Manganese levels in human whole saliva were determined using Neutron Activation Analysis (NAA) technique for the proposition of an indicative interval. The measurements were performed considering gender and lifestyle factors of Brazilian inhabitants (non-smokers, non-drinkers and no history of toxicological exposure). The results emphasize that the indicative interval is statistically different by gender. These data are useful for identifying or preventing some diseases in the Brazilian population. (author)

  3. Manganese concentration in human saliva using NAA

    International Nuclear Information System (INIS)

    Lewgoy, Hugo R.; Zamboni, Cibele B.; Medeiros, Ilca M.M.A.; Medeiros, Jose A.G. de

    2013-01-01

    In this investigation the Manganese levels in human whole saliva were determined using Neutron Activation Analysis (NAA) technique for the proposition of an indicative interval. The measurements were performed considering gender and lifestyle factors of Brazilian inhabitants (non-smokers, non-drinkers and no history of toxicological exposure). The results emphasize that the indicative interval is statistically different by gender. These data are useful for identifying or preventing some diseases in the Brazilian population. (author)

  4. Manganese contents of soils as determined by activation analysis

    International Nuclear Information System (INIS)

    El-Kholi, A.F.; Hamdy, A.A.; Al Metwally, A.I.; El-Damaty, A.H.

    1976-01-01

    The object of this investigation is to determine total manganese by means of neutron activation analysis and evaluate this technique in comparison with the corresponding data obtained by conventional chemical analysis. Data obtained revealed that the values of total manganese in calcareous soils obtained by both chemical analysis and that by neutron activation analysis were similar. Therefore, activation analysis could be recommended as a quick laboratory, less tedious, and time consuming method for the determination of Mn content in both soils and plants than the conventional chemical techniques due to its great specificity, sensitivity and simplicity. Statistical analysis showed that there is a significant correlation at 5% probability level between manganese content in Soybean plant and total manganese determined by activation and chemical analysis giving the evidence that in the case of those highly calcareous soils of low total manganese content this fraction has to be considered as far as available soil manganese is concerned

  5. Manganese deposition in drinking water distribution systems.

    Science.gov (United States)

    Gerke, Tammie L; Little, Brenda J; Barry Maynard, J

    2016-01-15

    This study provides a physicochemical assessment of manganese deposits on brass and lead components from two fully operational drinking water distributions systems. One of the systems was maintained with chlorine; the other, with secondary chloramine disinfection. Synchrotron-based in-situ micro X-ray adsorption near edge structure was used to assess the mineralogy. In-situ micro X-ray fluorescence mapping was used to demonstrate the spatial relationships between manganese and potentially toxic adsorbed metal ions. The Mn deposits ranged in thickness from 0.01 to 400 μm. They were composed primarily of Mn oxides/oxhydroxides, birnessite (Mn(3+) and Mn(4+)) and hollandite (Mn(2+) and Mn(4+)), and a Mn silicate, braunite (Mn(2+) and Mn(4+)), in varying proportions. Iron, chromium, and strontium, in addition to the alloying elements lead and copper, were co-located within manganese deposits. With the exception of iron, all are related to specific health issues and are of concern to the U.S. Environmental Protection Agency (U.S. EPA). The specific properties of Mn deposits, i.e., adsorption of metals ions, oxidation of metal ions and resuspension are discussed with respect to their influence on drinking water quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Manganese-enhanced magnetic resonance imaging (MEMRI).

    Science.gov (United States)

    Koretsky, Alan P; Silva, Afonso C

    2004-12-01

    Manganese ion (Mn2+) is an essential metal that participates as a cofactor in a number of critical biological functions, such as electron transport, detoxification of free radicals and synthesis of neurotransmitters. Mn2+ can enter excitable cells using some of the same transport systems as Ca2+ and it can bind to a number of intracellular sites because it has high affinity for Ca2+ and Mg2+ binding sites on proteins and nucleic acids. Paramagnetic forms of manganese ions are potent MRI relaxation agents. Indeed, Mn2+ was the first contrast agent proposed for use in MRI. Recently, there has been renewed interest in combining the strong MRI relaxation effects of Mn2+ with its unique biology, in order to further expand the already broad assortment of useful information that can be measured by MRI. Such an approach has been continuously developed in the past several years to provide unique tissue contrast, to assess tissue viability, to act as a surrogate marker of calcium influx into cells and to trace neuronal connections. This special issue of NMR in Biomedicine on manganese-enhanced MRI (MEMRI) is aimed at providing the readers of this journal with an extensive review of some of the most prominent applications of MEMRI in biological systems. Written by several of the leaders in the field, the reviews and original research articles featured in this special issue are likely to offer an exciting and inspiring view of the broad range of applications of MEMRI. Copyright 2004 John Wiley & Sons, Ltd.

  7. Manganese and the II system in photosynthesis

    International Nuclear Information System (INIS)

    Joyard, Jacques

    1971-01-01

    The evolution during greening of some components of system II of photosynthesis has been followed in plastids extracted from Zea mays grown in the dark. Manganese studies were done by means of neutron activation, electron spin resonance (ESR) was also used in some experiments. Oxygen evolution of isolated plastids was followed by polarography (with a membrane electrode). The evolution of manganese/carotenoids ratio can be divided in three parts. During the first hour of greening, the increase shows an input of Mn in the plastids; then, whereas carotenoids content of those plastids presents no changes, Mn is released in the medium; at last, carotenoids synthesis is parallel to Mn fixation in the plastids, the ratio being constant after 24 hours of greening. From various measurements on chloroplastic manganese, it is shown that the development of system II can be divided in two main phases: during the first one (that is during the first day of light) the components are not yet bound together but the relations become more and more strong. Then, during the last period of the development, the organisation of system II is complete and the transformations of the plastids are parallel to the raise of their activity. (author) [fr

  8. Metabolism of manganese, iron, copper, and selenium in calves

    International Nuclear Information System (INIS)

    Ho, S.Y.

    1981-01-01

    Sixteen male Holstein calves were used to study manganese and iron metabolism. The calves were fed one of the following diets for 18 days: control, control + iron, control + manganese, and control + iron and manganese. All calves were dosed orally with manganese-54. Tissue concentrations of manganese, iron and manganese-54 were determined. Small intestinal iron was lower in calves fed the high manganese diet than in controls. Tissue manganese-54 was lower in calves fed a high manganese diet. Fecal manganese content increased in calves fed both high manganese and high manganese-high iron diets. Serum total iron was not affected by the dietary treatments. To study the effects of high dietary levels of copper and selenium on the intracellular distributions of these two elements in liver and kidney cytosol, calves were fed one of four diets for 15 days. These were 0 and 100 ppM supplemental copper and 0 and 1 ppM added selenium. The control diet containing 0.1 ppM of selenium and 15 ppM of copper. All calves were orally dosed 48 hrs prior to sacrifice with selenium-75. A high copper diet increased copper concentrations in all intracellular liver fractions and most kidney fractions. Only the effects in the liver were significant. Less copper was found in the mitochondria fractions in liver and kidney of calves fed a high selenium diet. Three major copper-binding protein peaks were separated from the soluble fractions of calf liver and kidney. Peak 1 appeared to be the major copper-binding protein in liver and kidney cytosol of copper-loaded animals. Added selenium alone or in combination with copper accentuated the copper accumulation in this peak. Most of selenium-75 was recovered in the same peak as the copper. The results of this experiment indicated that the large molecular proteins in liver and kidney cytosol of calves play an important role in copper and selenium-75 metabolism

  9. Modeling Manganese Sorption and Surface Oxidation During Filtration

    OpenAIRE

    Bierlein, Kevin Andrew

    2012-01-01

    Soluble manganese (Mn) is a common contaminant in drinking water sources. High levels of Mn can lead to aesthetic water quality problems, necessitating removal of Mn during treatment to minimize consumer complaints. Mn may be removed during granular media filtration by the â natural greensand effect,â in which soluble Mn adsorbs to manganese oxide-coated (MnOx(s)) media and is then oxidized by chlorine, forming more manganese oxide. This research builds on a previous model developed by Mer...

  10. Nanostructured manganese oxides as highly active water oxidation catalysts: a boost from manganese precursor chemistry.

    Science.gov (United States)

    Menezes, Prashanth W; Indra, Arindam; Littlewood, Patrick; Schwarze, Michael; Göbel, Caren; Schomäcker, Reinhard; Driess, Matthias

    2014-08-01

    We present a facile synthesis of bioinspired manganese oxides for chemical and photocatalytic water oxidation, starting from a reliable and versatile manganese(II) oxalate single-source precursor (SSP) accessible through an inverse micellar molecular approach. Strikingly, thermal decomposition of the latter precursor in various environments (air, nitrogen, and vacuum) led to the three different mineral phases of bixbyite (Mn2 O3 ), hausmannite (Mn3 O4 ), and manganosite (MnO). Initial chemical water oxidation experiments using ceric ammonium nitrate (CAN) gave the maximum catalytic activity for Mn2 O3 and MnO whereas Mn3 O4 had a limited activity. The substantial increase in the catalytic activity of MnO in chemical water oxidation was demonstrated by the fact that a phase transformation occurs at the surface from nanocrystalline MnO into an amorphous MnOx (1manganese oxides including the newly formed amorphous MnOx . Both Mn2 O3 and the amorphous MnOx exhibit tremendous enhancement in oxygen evolution during photocatalysis and are much higher in comparison to so far known bioinspired manganese oxides and calcium-manganese oxides. Also, for the first time, a new approach for the representation of activities of water oxidation catalysts has been proposed by determining the amount of accessible manganese centers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Nanostructured manganese oxide thin films as electrode material for supercapacitors

    Science.gov (United States)

    Xia, Hui; Lai, Man On; Lu, Li

    2011-01-01

    Electrochemical capacitors, also called supercapacitors, are alternative energy storage devices, particularly for applications requiring high power densities. Recently, manganese oxides have been extensively evaluated as electrode materials for supercapacitors due to their low cost, environmental benignity, and promising supercapacitive performance. In order to maximize the utilization of manganese oxides as the electrode material for the supercapacitors and improve their supercapacitive performance, the nanostructured manganese oxides have therefore been developed. This paper reviews the synthesis of the nanostructured manganese oxide thin films by different methods and the supercapacitive performance of different nanostructures.

  12. Manganese Catalyzed C–H Halogenation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wei; Groves, John T.

    2015-06-16

    The remarkable aliphatic C–H hydroxylations catalyzed by the heme-containing enzyme, cytochrome P450, have attracted sustained attention for more than four decades. The effectiveness of P450 enzymes as highly selective biocatalysts for a wide range of oxygenation reactions of complex substrates has driven chemists to develop synthetic metalloporphyrin model compounds that mimic P450 reactivity. Among various known metalloporphyrins, manganese derivatives have received considerable attention since they have been shown to be versatile and powerful mediators for alkane hydroxylation and olefin epoxidation. Mechanistic studies have shown that the key intermediates of the manganese porphyrin-catalyzed oxygenation reactions include oxo- and dioxomanganese(V) species that transfer an oxygen atom to the substrate through a hydrogen abstraction/oxygen recombination pathway known as the oxygen rebound mechanism. Application of manganese porphyrins has been largely restricted to catalysis of oxygenation reactions until recently, however, due to ultrafast oxygen transfer rates. In this Account, we discuss recently developed carbon–halogen bond formation, including fluorination reactions catalyzed by manganese porphyrins and related salen species. We found that biphasic sodium hypochlorite/manganese porphyrin systems can efficiently and selectively convert even unactivated aliphatic C–H bonds to C–Cl bonds. An understanding of this novel reactivity derived from results obtained for the oxidation of the mechanistically diagnostic substrate and radical clock, norcarane. Significantly, the oxygen rebound rate in Mn-mediated hydroxylation is highly correlated with the nature of the trans-axial ligands bound to the manganese center (L–MnV$=$O). Based on the ability of fluoride ion to decelerate the oxygen rebound step, we envisaged that a relatively long-lived substrate radical could be trapped by a Mn–F fluorine source, effecting carbon–fluorine bond

  13. Battery recycling: recovery of manganese in the form of electrolytic manganese dioxide

    International Nuclear Information System (INIS)

    Roriz, Elizabeth Rodrigues Rangel; Von Krüge, Paulo; Espinosa, Denise Crocce Romano; Tenorio, Jorge Alberto Soares

    2010-01-01

    This work seeks to verify the possibility of using depleted batteries as a source of manganese applying the electrolytic process, considering the growing demand for products containing manganese in their composition. It was used an electrolyte solution containing the metal ions: Ca (270mg / L), Ni (3000 mg / L), Co (630 mg / L), Mn (115.300 mg / L) , Ti (400 mg / L) and Pb (20 mg / L) in concentrated sulfuric acid. The production of electrolytic manganese dioxide (EMD) was performed through galvanization using a stabilized source that monitored the potential of the working electrode. It was used an electrode of lead and two counter electrodes of graphite at a temperature of 98 deg C (± 2 deg C) and current density of 1.69A.dm"-"2. The material obtained was analyzed through the process of X-ray fluorescence spectrometry and X-ray diffraction. The results indicated that it is possible to obtain electrolytic manganese dioxide with a purity of about 94% and that the main allotropic variety obtained under the conditions of the experiment was the ε-MnO_2. (author)

  14. Fatal manganese intoxication due to an error in the elaboration of Epsom salts for a liver cleansing diet.

    Science.gov (United States)

    Sánchez, Baltasar; Casalots-Casado, Jaume; Quintana, Salvador; Arroyo, Amparo; Martín-Fumadó, Carles; Galtés, Ignasi

    2012-11-30

    We describe the case of a 50-year-old man with a fatal intoxication after accidental massive oral ingestion of manganese. The patient presented with lethargy, diffuse abdominal pain, vomiting, and profuse diarrhea after ingesting Epsom salts (magnesium sulfate heptahydrate) during a liver cleansing diet. Despite intensive care management with intubation, prone position ventilation, continuous venovenous hemofiltration, and multiple transfusions, he progressed to refractory shock with multiple organ dysfunction resulting in death within 72 h. Similar patients arrived at several hospitals with identical epidemiology (all had ingested the same salt obtained in the same place). Clinical and forensic investigations (X-ray diffraction) discovered that the supplier had mistakenly prepared the salts with hydrated manganese sulfate instead of magnesium sulfate heptahydrate. The results enabled the other patients to be successfully treated for hydrated manganese sulfate intoxication with life support in the intensive care unit and chelation therapy (EDTA). We describe the clinical presentation of acute manganese poisoning and alert professionals to the risk of an increasingly popular diet. This case demonstrates the importance of collaboration between clinicians, pathologists, and forensic scientists to resolve a difficult-to-diagnose case. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria.

    Science.gov (United States)

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-11-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the prevailing terminal electron-accepting process in anoxic incubations of surface sediments, and even the addition of acetate stimulated neither iron nor sulfate reduction. The three geographically distinct sediments harbored surprisingly similar communities of acetate-utilizing manganese-reducing bacteria: 16S rRNA of members of the genera Colwellia and Arcobacter and of novel genera within the Oceanospirillaceae and Alteromonadales were detected in heavy RNA-SIP fractions from these three sediments. Most probable number (MPN) analysis yielded up to 10(6) acetate-utilizing manganese-reducing cells cm(-3) in Gullmar Fjord sediment. A 16S rRNA gene clone library that was established from the highest MPN dilutions was dominated by sequences of Colwellia and Arcobacter species and members of the Oceanospirillaceae, supporting the obtained RNA-SIP results. In conclusion, these findings strongly suggest that (i) acetate-dependent manganese reduction in manganese oxide-rich sediments is catalyzed by members of taxa (Arcobacter, Colwellia and Oceanospirillaceae) previously not known to possess this physiological function, (ii) similar acetate-utilizing manganese reducers thrive in geographically distinct regions and (iii) the identified manganese reducers differ greatly from the extensively explored iron reducers in marine sediments.

  16. Synthesis and characterization of monomeric manganese(II) and ...

    African Journals Online (AJOL)

    The geometry at the manganese center is seven-coordinate, and is best described as a capped trigonal pyramid with the water molecule forming the cap and the six nitrogen atoms of the tpen ligand occupying the pyramidal sites. The manganese atom and the water molecule lie on a crystallographic twofold axis.

  17. Adsorptive removal of manganese, arsenic and iron from groundwater

    NARCIS (Netherlands)

    Buamah, R.

    2009-01-01

    Arsenic, manganese and iron in drinking water at concentrations exceeding recommended guideline values pose health risks and aesthetic defects. Batch and pilot experiments on manganese adsorption equilibrium and kinetics using iron-oxide coated sand (IOCS), Aquamandix and other media have been

  18. Behavior of manganese ion in basic medium: consequence for the ...

    African Journals Online (AJOL)

    Dr. J. T. Ekanem

    2006-01-25

    Jan 25, 2006 ... adding manganese chloride or manganese sulfate to sodium hydroxyde or sodium carbonate in aqueous ... carbonate (1 M). The release of p- nitrophenoxide anion (pNP) was quantified at. 420 nm using a spectrophotometer (Spectronic. Genesis 5). .... These curves were bell-type with an ascending.

  19. Bioconcentration of manganese and iron in Panaeoloideae Sing

    NARCIS (Netherlands)

    Stijve, T.; Blake, C.

    1994-01-01

    According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae,

  20. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium calcium manganese strontium... Specific Chemical Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium calcium...

  1. Characterization and concentration of manganese ore waste

    International Nuclear Information System (INIS)

    Lima, Rosa Malena Fernandes; Pereira, Eder Esper; Reis, Erica Linhares; Silva, Glaucia Regina da

    2010-01-01

    In this work is presented the tests results of characterization and concentration by gravity and flotation methods carried out with a manganese sample waste. By optical microscopy, SEM/EDS and X-ray diffractometry were identified the Mn minerals spessartite (20%), tephroite (15%), rhodonite (5%), rhodochrosite and carbonates minerals (29%), opaque minerals and others (16%), micaceus minerals (6%) and quartz (4%). It was obtained Mn metallurgical recovery of 58% with Mn concentrate contents varying from 30 to 32.5%. The concentrates SiO_2 contents of flotation were until 1.5% smaller than those contents of gravity method concentrates. (author)

  2. Manganese accumulation in the brain: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Nomiyama, K.; Takase, Y.; Nakazono, T.; Nojiri, J.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan); Noguchi, T. [Kyushu University, Department of Clinical Radiology, Graduate School of Medicine, Fukuoka (Japan)

    2007-09-15

    Manganese (Mn) accumulation in the brain is detected as symmetrical high signal intensity in the globus pallidi on T1-weighted MR images without an abnormal signal on T2-weighted images. In this review, we present several cases of Mn accumulation in the brain due to acquired or congenital diseases of the abdomen including hepatic cirrhosis with a portosystemic shunt, congenital biliary atresia, primary biliary cirrhosis, congenital intrahepatic portosystemic shunt without liver dysfunction, Rendu-Osler-Weber syndrome with a diffuse intrahepatic portosystemic shunt, and patent ductus venosus. Other causes of Mn accumulation in the brain are Mn overload from total parenteral nutrition and welding-related Mn intoxication. (orig.)

  3. Alternative irradiation system for efficiency manganese bath determination

    Energy Technology Data Exchange (ETDEWEB)

    Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Xavier da Silva, Ademir, E-mail: ademir@con.ufrj.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil)

    2010-12-15

    An alternative irradiation system, which works with a radionuclide neutron source and manganese sulphate solution volume have been proposed for efficiency determination of a Manganese Bath System (MBS). This irradiation system was designed by simulation with MCNP5 code, considering a californium neutron source in several manganese sulphate volumes and different neutron reflectors. Although its solution specific activity are less than those in nuclear reactors, the simulation results have showed that the irradiation system proposed takes a manganese neutron capture increase up to 200 times when it compared to manganese neutron capture from a MBS whose diameter is about 100 cm. That becomes possible to use those samples for some of the absolute specific activity measuring methods.

  4. Defining Quantum Control Flow

    OpenAIRE

    Ying, Mingsheng; Yu, Nengkun; Feng, Yuan

    2012-01-01

    A remarkable difference between quantum and classical programs is that the control flow of the former can be either classical or quantum. One of the key issues in the theory of quantum programming languages is defining and understanding quantum control flow. A functional language with quantum control flow was defined by Altenkirch and Grattage [\\textit{Proc. LICS'05}, pp. 249-258]. This paper extends their work, and we introduce a general quantum control structure by defining three new quantu...

  5. Can play be defined?

    DEFF Research Database (Denmark)

    Eichberg, Henning

    2015-01-01

    Can play be defined? There is reason to raise critical questions about the established academic demand that at phenomenon – also in humanist studies – should first of all be defined, i.e. de-lineated and by neat lines limited to a “little box” that can be handled. The following chapter develops....... Human beings can very well understand play – or whatever phenomenon in human life – without defining it....

  6. Diffusion abnormalities of the globi pallidi in manganese neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    McKinney, Alexander M.; Filice, Ross W.; Teksam, Mehmet; Casey, Sean; Truwit, Charles; Clark, H. Brent; Woon, Carolyn; Liu, Hai Ying [Department of Radiology, Medical School, Box 292, 420 Delaware Street S.E., 55455, Minneapolis, MN (United States)

    2004-04-01

    Manganese is an essential trace metal required for normal central nervous system function, which is toxic when in excess amounts in serum. Manganese neurotoxicity has been demonstrated in patients with chronic liver/biliary failure where an inability to excrete manganese via the biliary system causes increased serum levels, and in patients on total parenteral nutrition (TPN), occupational/inhalational exposure, or other source of excess exogenous manganese. Manganese has been well described in the literature to deposit selectively in the globi pallidi and to induce focal neurotoxicity. We present a case of a 53-year-old woman who presented for a brain MR 3 weeks after liver transplant due to progressively decreasing level of consciousness. The patient had severe liver failure by liver function tests and bilirubin levels, and had also been receiving TPN since the transplant. The MR demonstrated symmetric hyperintensity on T1-weighted images in the globi pallidi. Apparent diffusion coefficient (ADC) map indicated restricted diffusion in the globi pallidi bilaterally. The patient eventually succumbed to systemic aspergillosis 3 days after the MR. The serum manganese level was 195 mcg/l (micrograms per liter) on postmortem exam (over 20 times the upper limits of normal). The patient was presumed to have suffered from manganese neurotoxicity since elevated serum manganese levels have been shown in the literature to correlate with hyperintensity on T1-weighted images, neurotoxicity symptoms, and focal concentration of manganese in the globi pallidi. Neuropathologic sectioning of the globi pallidi at autopsy was also consistent with manganese neurotoxicity. (orig.)

  7. Reduction of ripening time of full-scale manganese removal filters with manganese oxide-coated media

    NARCIS (Netherlands)

    Bruins, J.H.; Petrusevski, B.; Slokar, Y.M.; Huysman, K.; Joris, K.; Kruithof, J.C.; Kennedy, M.D.

    2015-01-01

    Effective manganese removal by conventional aeration-filtration with virgin filter media requires a long ripening time. The aim of this study was to assess the potential of manganese oxide-coated media to shorten the ripening time of filters with virgin media, under practical conditions. A full

  8. Ferromagnetic properties of manganese doped iron silicide

    Science.gov (United States)

    Ruiz-Reyes, Angel; Fonseca, Luis F.; Sabirianov, Renat

    We report the synthesis of high quality Iron silicide (FeSi) nanowires via Chemical Vapor Deposition (CVD). The materials exhibits excellent magnetic response at room temperature, especially when doped with manganese showing values of 2.0 X 10-04 emu for the FexMnySi nanowires. SEM and TEM characterization indicates that the synthesized nanowires have a diameter of approximately 80nm. MFM measurements present a clear description of the magnetic domains when the nanowires are doped with manganese. Electron Diffraction and XRD measurements confirms that the nanowires are single crystal forming a simple cubic structure with space group P213. First-principle calculations were performed on (111) FeSi surface using the Vienna ab initio simulation package (VASP). The exchange correlations were treated under the Ceperley-Alder (CA) local density approximation (LDA). The Brillouin Zone was sampled with 8x8x1 k-point grid. A total magnetic moment of about 10 μB was obtained for three different surface configuration in which the Iron atom nearest to the surface present the higher magnetization. To study the effect of Mn doping, Fe atom was replaced for a Mn. Stronger magnetization is presented when the Mn atom is close to the surface. The exchange coupling constant have been evaluated calculating the energy difference between the ferromagnetic and anti-ferromagnetic configurations.

  9. Iron and manganese removal from drinking water

    Directory of Open Access Journals (Sweden)

    Daniela-Elena Pascu

    2016-04-01

    Full Text Available The purpose of the present study is to find a suitable method for removal of iron and manganese from ground water, considering bothlocal economical and environmental aspects. Ground water is a highly important source of drinking water in Romania. Ground water is naturally pure from bacteria at a 25 m depth or more. However, solved metals may occur and if the levels are too high, the water is not drinkable. Different processes, such as electrochemical and combined electrochemical-adsorption methods have been applied to determine metals content in accordance to reports of National Water Agency from Romania (ANAR. Every water source contains dissolved or particulate compounds. The concentrations of these compounds can affect health, productivity, compliance requirements, or serviceability and cannot be economically removed by conventional filtration means. In this study, we made a comparison between the electrochemical and adsorption methods (using membranes. Both methods have been used to evaluate the efficiency of iron and manganese removal at various times and temperatures. We used two membrane types: composite and cellulose, respectively. Different approaches, including lowering the initial current density and increasing the initial pH were applied. Reaction kinetics was achieved using mathematical models: Jura and Temkin.

  10. Simple synthetic route to manganese-containing nanowires with the spinel crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lei; Zhang, Yan; Hudak, Bethany M.; Wallace, Damon K.; Kim, Doo Young; Guiton, Beth S.

    2016-08-15

    This report describes a new route to synthesize single-crystalline manganese-containing spinel nanowires (NWs) by a two-step hydrothermal and solid-state synthesis. Interestingly, a nanowire or nanorod morphology is maintained during conversion from MnO{sub 2}/MnOOH to CuMn{sub 2}O{sub 4}/Mg{sub 2}MnO{sub 4}, despite the massive structural rearrangement this must involve. Linear sweep voltammetry (LSV) curves of the products give preliminary demonstration that CuMn{sub 2}O{sub 4} NWs are catalytically active towards the oxygen evolution reaction (OER) in alkaline solution, exhibiting five times the magnitude of current density found with pure carbon black. - Highlights: • Synthesis of single-crystalline manganese-containing spinel nanowires. • Binary oxide nanowire converted to ternary oxide wire through solid state reaction. • Approach to structure conversion with shape retention could be generally applicable. • Copper and Manganese display multiple oxidation states with potential for catalysis. • CuMn{sub 2}O{sub 4} nanowires show promise as catalysts for the oxygen evolution reaction.

  11. Transcriptome Analysis of Manganese-deficient Chlamydomonas reinhardtii Provides Insight on the Chlorophyll Biosynthesis Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lockhart, Ainsley; Zvenigorodsky, Natasha; Pedraza, Mary Ann; Lindquist, Erika

    2011-08-11

    The biosynthesis of chlorophyll and other tetrapyrroles is a vital but poorly understood process. Recent genomic advances with the unicellular green algae Chlamydomonas reinhardtii have created opportunity to more closely examine the mechanisms of the chlorophyll biosynthesis pathway via transcriptome analysis. Manganese is a nutrient of interest for complex reactions because of its multiple stable oxidation states and role in molecular oxygen coordination. C. reinhardtii was cultured in Manganese-deplete Tris-acetate-phosphate (TAP) media for 24 hours and used to create cDNA libraries for sequencing using Illumina TruSeq technology. Transcriptome analysis provided intriguing insight on possible regulatory mechanisms in the pathway. Evidence supports similarities of GTR (Glutamyl-tRNA synthase) to its Chlorella vulgaris homolog in terms of Mn requirements. Data was also suggestive of Mn-related compensatory up-regulation for pathway proteins CHLH1 (Manganese Chelatase), GUN4 (Magnesium chelatase activating protein), and POR1 (Light-dependent protochlorophyllide reductase). Intriguingly, data suggests possible reciprocal expression of oxygen dependent CPX1 (coproporphyrinogen III oxidase) and oxygen independent CPX2. Further analysis using RT-PCR could provide compelling evidence for several novel regulatory mechanisms in the chlorophyll biosynthesis pathway.

  12. Biological removal of iron and manganese in rapid sand filters - Process understanding of iron and manganese removal

    DEFF Research Database (Denmark)

    Lin, Katie

    to precipitation and corrosion. Manganese and iron can either be removed physico-chemically or biologically or combined. The physico-chemical oxidation and precipitation of manganese can theoretically be achieved by aeration, but this process is slow unless pH is raised far above neutral, making the removal...... of manganese by simple aeration and precipitation under normal drinking water treatment conditions insignificant. Manganese may also be oxidized autocatalytically. Iron is usually easier to remove. First, iron is rapidly chemically oxidized by oxygen at neutral pH followed by precipitation and filtration......-filter, where iron is removed. Step 2: Filtration in an after-filter where e.g. ammonium and manganese is removed. The treatment relies on microbial processes and may present an alternative, greener and more sustainable approach for drinking water production spending less chemicals and energy than chemical (e...

  13. MULTIPLE OBJECTS

    Directory of Open Access Journals (Sweden)

    A. A. Bosov

    2015-04-01

    Full Text Available Purpose. The development of complicated techniques of production and management processes, information systems, computer science, applied objects of systems theory and others requires improvement of mathematical methods, new approaches for researches of application systems. And the variety and diversity of subject systems makes necessary the development of a model that generalizes the classical sets and their development – sets of sets. Multiple objects unlike sets are constructed by multiple structures and represented by the structure and content. The aim of the work is the analysis of multiple structures, generating multiple objects, the further development of operations on these objects in application systems. Methodology. To achieve the objectives of the researches, the structure of multiple objects represents as constructive trio, consisting of media, signatures and axiomatic. Multiple object is determined by the structure and content, as well as represented by hybrid superposition, composed of sets, multi-sets, ordered sets (lists and heterogeneous sets (sequences, corteges. Findings. In this paper we study the properties and characteristics of the components of hybrid multiple objects of complex systems, proposed assessments of their complexity, shown the rules of internal and external operations on objects of implementation. We introduce the relation of arbitrary order over multiple objects, we define the description of functions and display on objects of multiple structures. Originality.In this paper we consider the development of multiple structures, generating multiple objects.Practical value. The transition from the abstract to the subject of multiple structures requires the transformation of the system and multiple objects. Transformation involves three successive stages: specification (binding to the domain, interpretation (multiple sites and particularization (goals. The proposed describe systems approach based on hybrid sets

  14. Determination of semi-empirical relationship between the manganese and hydrogen atoms ratio, physical density and concentration in an aqueous solution of manganese sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues Bittencourt, Guilherme, E-mail: bittencourt@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil)

    2010-12-15

    The Manganese sulphate solution has been used for neutron metrology through the method of Manganese Bath. This method uses physical parameters of manganese sulphate solution to obtain its corrections. This work established a functional relationship, using the gravimetric method, between those physical parameters: density, concentration and hydrogen to manganese ratio. Comparisons were done between manganese sulphate solution concentration from the Manganese Bath system of Laboratory of Metrology of Ionising Radiation and estimated values from the functional relationship obtained, showing percentage difference of less than 0.1%. This result demonstrates the usefulness in the correlation of the physical values of the solution to the MB.

  15. Removal of Iron and Manganese in Groundwater using Natural Biosorbent

    Science.gov (United States)

    Baharudin, F.; Tadza, M. Y. Mohd; Imran, S. N. Mohd; Jani, J.

    2018-04-01

    This study was conducted to measure and compare the concentration of iron, manganese and hardness of the river and groundwater and to determine the effectiveness of iron and manganese removal by using natural biosorbent which is banana peels. The samples of river and groundwater were collected at riverbank filtration site at Jenderam Hilir, Dengkil. Based on the water quality investigation, the concentration of iron and manganese in the samples of groundwater have exceeded the drinking water quality standard which are 0.3 mg/L for iron and 0.1 mg/L for manganese. The removal process of the iron and manganese in the groundwater was done by using 2, 4 and 8 grams of banana peels activated carbon. It is found that with higher amount of activated banana peels, the removal of iron and manganese is more effective. The ranges of percentage of iron and manganese removal are between 82.25% to 90.84% and 98.79% to 99.43% respectively. From the result, banana peels activated carbon can be concluded as a one of the most effective low-cost adsorbent for groundwater treatment.

  16. Facile N...N coupling of manganese(V) imido species.

    Science.gov (United States)

    Yiu, Shek-Man; Lam, William W Y; Ho, Chi-Ming; Lau, Tai-Chu

    2007-01-31

    (Salen)manganese(V) nitrido species are activated by electrophiles such as trifluoroacetic anhydride (TFAA) or trifluoroacetic acid (TFA) to produce N2. Mechanistic studies suggest that the manganese(V) nitrido species first react with TFAA or TFA to produce an imido species, which then undergoes N...N coupling. It is proposed that the resulting manganese(III) mu-diazene species decomposes via internal redox to give N2 and manganese(II). The manganese(II) species is then rapidly oxidized by manganese(V) imide to give manganese(III) and CF3CONH2 (for TFAA) or NH3 (for TFA).

  17. Oxidative damage and neurodegeneration in manganese-induced neurotoxicity

    International Nuclear Information System (INIS)

    Milatovic, Dejan; Zaja-Milatovic, Snjezana; Gupta, Ramesh C.; Yu, Yingchun; Aschner, Michael

    2009-01-01

    Exposure to excessive manganese (Mn) levels results in neurotoxicity to the extrapyramidal system and the development of Parkinson's disease (PD)-like movement disorder, referred to as manganism. Although the mechanisms by which Mn induces neuronal damage are not well defined, its neurotoxicity appears to be regulated by a number of factors, including oxidative injury, mitochondrial dysfunction and neuroinflammation. To investigate the mechanisms underlying Mn neurotoxicity, we studied the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates (HEP), neuroinflammation mediators and associated neuronal dysfunctions both in vitro and in vivo. Primary cortical neuronal cultures showed concentration-dependent alterations in biomarkers of oxidative damage, F 2 -isoprostanes (F 2 -IsoPs) and mitochondrial dysfunction (ATP), as early as 2 h following Mn exposure. Treatment of neurons with 500 μM Mn also resulted in time-dependent increases in the levels of the inflammatory biomarker, prostaglandin E 2 (PGE 2 ). In vivo analyses corroborated these findings, establishing that either a single or three (100 mg/kg, s.c.) Mn injections (days 1, 4 and 7) induced significant increases in F 2 -IsoPs and PGE 2 in adult mouse brain 24 h following the last injection. Quantitative morphometric analyses of Golgi-impregnated striatal sections from mice exposed to single or three Mn injections revealed progressive spine degeneration and dendritic damage of medium spiny neurons (MSNs). These findings suggest that oxidative stress, mitochondrial dysfunction and neuroinflammation are underlying mechanisms in Mn-induced neurodegeneration.

  18. High speed TV-towing system for exploration manganese nodules

    International Nuclear Information System (INIS)

    Hartmann, P.

    1977-12-01

    For the oceanographic, special for the manganese nodules exploration in the deep sea a high speed-TV-towing system is to design on base of existing TV-towing systems to get better efficiency during the exploration phase. It is planned to increase to towing speed at the time of 2 knots up to 6-8 knots. The essential points of developments in this direction are 1) to decrease the hydrodynamical drag of the long towing cable with fairings. 2) To seperate to towing system into two units the passiv controlled towing cable end point 'SEP' with negativ buoyancy (weight) and the activ controlled TV-fish. With this separation it is possible to tow the TV-fish within a defined accuracy parallel to the sea floor without an influence to the overall system. 3) To adapt the TV- and photo stobe light unit for these towing conditions (high speed). 4) To design the control concept, the operating equipment, the energy and data transmission system, the towed body concept, the hydrodynamical calculation of towing phase and the other towed components. The results of this study is the definition of a two body towing system which is able towed by a research vessel to make continously TV-observation of the sea floor in depth down to 6,000 meters. (orig.) [de

  19. Electron-tunneling observation of localized excited states in superconducting manganese-doped lead

    International Nuclear Information System (INIS)

    Tsang, J.; Ginsberg, D.M.

    1980-01-01

    We have made electron-tunneling measurements on a dilute, superconducting lead-manganese alloy. A well-defined structure was observed in the ac-conductance--voltage curves, indicating excited states within the BCS energy gap. These states were partially accounted for by Shiba theory when spin-dependent s-, p-, and d-wave scattering were included. The phase shifts used in doing that were the results of band calculations. The experimental data also show the existence of a broad background density of states in the energy gap, which cannot be accounted for by the theory

  20. The effect of adding urea, manganese and linoleic acid to wheat straw and wood chips on lignin degradation by fungi and subsequent

    NARCIS (Netherlands)

    Kuijk, van S.J.A.; Sonnenberg, A.S.M.; Baars, J.J.P.; Hendriks, W.H.; Cone, J.W.

    2016-01-01

    The aim of this study was optimizing Ceriporiopsis subvermispora and Lentinula edodes pre-treatment of wheat straw and wood chips by adding urea, manganese and linoleic acid. Optimization was defined as more lignin degradation and an increase in in vitro gas

  1. Defining Overweight and Obesity

    Science.gov (United States)

    ... Micronutrient Malnutrition State and Local Programs Defining Adult Overweight and Obesity Recommend on Facebook Tweet Share Compartir ... weight for a given height is described as overweight or obese. Body Mass Index, or BMI, is ...

  2. Drinking Levels Defined

    Science.gov (United States)

    ... of Alcohol Consumption Alcohol's Effects on the Body Alcohol Use Disorder Fetal Alcohol Exposure Support & Treatment Alcohol Policy Special ... Definition of Drinking at Low Risk for Developing Alcohol Use Disorder (AUD): For women, low-risk drinking is defined ...

  3. Defining Documentary Film

    DEFF Research Database (Denmark)

    Juel, Henrik

    2006-01-01

    A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film......A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film...

  4. Brain manganese, catecholamine turnover, and the development of startle in rats prenatally exposed to manganese

    International Nuclear Information System (INIS)

    Kontur, P.J.; Fechter, L.D.

    1985-01-01

    Manganese (Mn) can be neurotoxic when present in high concentrations. Neonatal animals show differential absorption, accumulation, and excretion of Mn relative to adults. If similar kinetic differences exist during gestation, then fetal animals may be susceptible to Mn neurotoxicity. The objective of this study was to examine maternal-fetal Mn transfer and the susceptibility of prenatal animals to Mn neurotoxicity. This was approached by studying the ability of Mn to cross the placenta and reach the fetal central nervous system using radiotracer and atomic absorption spectroscopy techniques. Manganese is thought to disrupt catecholamine neurotransmission in the central nervous system. This was examined in newborn rats by alpha-methyl-para-tyrosine induced catecholamine turnover and the development of the acoustic startle response. The results suggest that there are limits on fetal Mn accumulation under conditions of both normal and excessive dietary Mn levels. Manganese accumulation in the fetal brain after exposure to increased dietary Mn does not alter either dopamine or norepinephrine turnover or the development of the acoustic startle response. Excess Mn does not appear to be neurotoxic to fetal rats in spite of its limited accumulation in nervous tissue after gestational exposure

  5. Manganese superoxide dismutase and breast cancer recurrence

    DEFF Research Database (Denmark)

    Cronin-Fenton, Deirdre P; Christensen, Mariann; Lash, Timothy L

    2014-01-01

    BACKGROUND: Manganese superoxide dismutase (MnSOD) inhibits oxidative damage and cancer therapy effectiveness. A polymorphism in its encoding gene (SOD2: Val16Ala rs4880) may confer poorer breast cancer survival, but data are inconsistent. We examined the association of SOD2 genotype and breast......-metastatic breast cancer from 1990-2001, received adjuvant Cyclo, and were registered in the Danish Breast Cancer Cooperative Group. We identified 118 patients with BCR and 213 matched breast cancer controls. We genotyped SOD2 and used conditional logistic regression to compute the odds ratio (OR) and associated 95...... cancer recurrence (BCR) among patients treated with cyclophosphamide-based chemotherapy (Cyclo). We compared our findings with published studies using meta-analyses. METHODS: We conducted a population-based case-control study of BCR among women in Jutland, Denmark. Subjects were diagnosed with non...

  6. An Interactive Signed Distance Approach for Multiple Criteria Group Decision-Making Based on Simple Additive Weighting Method with Incomplete Preference Information Defined by Interval Type-2 Fuzzy Sets

    OpenAIRE

    Ting-Yu Chen

    2014-01-01

    Interval type-2 fuzzy sets (T2FSs) with interval membership grades are suitable for dealing with imprecision or uncertainties in many real-world problems. In the Interval type-2 fuzzy context, the aim of this paper is to develop an interactive signed distance-based simple additive weighting (SAW) method for solving multiple criteria group decision-making problems with linguistic ratings and incomplete preference information. This paper first formulates a group decision-making problem with unc...

  7. Phase transformations in Higher Manganese Silicides

    Energy Technology Data Exchange (ETDEWEB)

    Allam, A. [MADIREL, UMR 7246 CNRS - Universite Aix-Marseille, av Normandie-Niemen, 13397 Marseille Cedex 20 (France); IM2NP, UMR 7334 CNRS - Universite Aix-Marseille, av Normandie-Niemen, Case 142, 13397 Marseille Cedex 20 (France); Boulet, P. [MADIREL, UMR 7246 CNRS - Universite Aix-Marseille, av Normandie-Niemen, 13397 Marseille Cedex 20 (France); Nunes, C.A. [Departamento de Engenharia de Materiais (DEMAR), Escola de Engenharia de Lorena (EEL), Universidade de Sao Paulo - USP, Caixa Postal 116, 12600-970 Lorena, Sao Paulo (Brazil); Sopousek, J.; Broz, P. [Masaryk University, Faculty of Science, Department of Chemistry, Kolarska 2, 611 37 Brno (Czech Republic); Masaryk University, Central European Institute of Technology, CEITEC, Kamenice 753/5, 625 00 Brno (Czech Republic); Record, M.-C., E-mail: m-c.record@univ-cezanne.fr [IM2NP, UMR 7334 CNRS - Universite Aix-Marseille, av Normandie-Niemen, Case 142, 13397 Marseille Cedex 20 (France)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer The phase transitions of the Higher Manganese Silicides were investigated. Black-Right-Pointing-Pointer The samples were characterised by XRD, DTA and DSC. Black-Right-Pointing-Pointer Mn{sub 27}Si{sub 47} is the stable phase at room temperature and under atmospheric pressure. Black-Right-Pointing-Pointer At around 800 Degree-Sign C, Mn{sub 27}Si{sub 47} is transformed into Mn{sub 15}Si{sub 26}. Black-Right-Pointing-Pointer The phase transition is of a second order. - Abstract: This work is an investigation of the phase transformations of the Higher Manganese Silicides in the temperature range [100-1200 Degree-Sign C]. Several complementary experimental techniques were used, namely in situ X-ray Diffraction (XRD), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). The evolution of both the lattice parameters and the thermal expansion coefficients was determined from in situ XRD measurements. The stability of the samples was investigated by thermal analysis (DTA) and Cp measurements (DSC). This study shows that Mn{sub 27}Si{sub 47} which is the stable phase at room temperature and under atmospheric pressure undergoes a phase transformation at around 800 Degree-Sign C. Mn{sub 27}Si{sub 47} is transformed into Mn{sub 15}Si{sub 26}. This phase transformation seems to be of a second order one. Indeed it was not evidenced by DTA and by contrast it appears on the Cp curve.

  8. Correlation between airborne manganese concentration at the workstations in the iron foundry and manganese concentration in workers’ blood

    Directory of Open Access Journals (Sweden)

    Seyedtaghi Mirmohammadi

    2017-08-01

    Full Text Available Background: Manganese (Mn used as raw material for melting process in the ferrous foundry is considered as hazardous neurotoxic substance because it accumulates in the central nervous system and may cause neurological disorders. The furnace-men and melting department workers are potentially exposed to manganese particles or fume in the workplace. The objective of the research has been to investigate the sources and levels of manganese exposure in the foundry by correlation of blood-manganese (B-Mn and air-manganese (air-Mn measurement. Material and Methods: Air-Mn and Mn of blood serum were measured involving workers who worked in a big-sized foundry during 1 year. The standard method of the Occupational Safety and Health Administration (OSHA ID-121 was used for air and blood assessment and atomic absorption spectroscopy (AAS was carried out for air and blood sample analysis. Results: The air sampling results have revealed that there is a high exposure to manganese (4.5 mg/m3 in the workplace as compared to the National Institute for Occupational Safety and Health’s (NIOSH time weighted average (the reference time-weighted average (TWA = 1 mg/m3. The average blood serum Mn concentration was 2.745 μg/l for subjects working for shorter than 3 months and 274.85 μg/l for subjects working 3–12 months. Conclusions: Against the research hypothesis there was no correlation between the air-Mn concentration and the B-Mn (serum level of manganese in the serum of the exposed subjects. It may be due to short time of air sampling of manganese airborne particles, and a real-time monitoring of airborne manganese particles is suggested for any future study. Med Pr 2017;68(4:449–458

  9. Definably compact groups definable in real closed fields. I

    OpenAIRE

    Barriga, Eliana

    2017-01-01

    We study definably compact definably connected groups definable in a sufficiently saturated real closed field $R$. We introduce the notion of group-generic point for $\\bigvee$-definable groups and show the existence of group-generic points for definably compact groups definable in a sufficiently saturated o-minimal expansion of a real closed field. We use this notion along with some properties of generic sets to prove that for every definably compact definably connected group $G$ definable in...

  10. High levels of hair manganese in children living in the vicinity of a ferro-manganese alloy production plant.

    Science.gov (United States)

    Menezes-Filho, José A; Paes, Ciro R; Pontes, Angela M de C; Moreira, Josino C; Sarcinelli, Paula N; Mergler, Donna

    2009-11-01

    Manganese (Mn) is an essential element, but an effective toxic at high concentrations. While there is an extensive literature on occupational exposure, few studies have examined adults and children living near important sources of airborne Mn. The objective of this study was to analyze hair Mn of children living in the vicinity of a ferro-manganese alloy production plant in the Great Salvador region, State of Bahia, Brazil and examine factors that influence this bioindicator of exposure. We examined 109 children in the age range of 1-10 years, living near the plant. Four separate housing areas were identified a priori on the bases of proximity to the emission sources and downwind location. A non-exposed group (n=43) of similar socio-economic status was also evaluated. Mn hair (MnH) concentration was measured by graphite atomic absorption spectrometry (GFAAS). Possible confounding hematological parameters were also assessed. Mean MnH concentration was 15.20 microg/g (1.10-95.50 microg/g) for the exposed children and 1.37 microg/g (0.39-5.58 microg/g) for the non-exposed. For the former, MnH concentrations were 7.95+/-1.40 microg/g (farthest from the plant), 11.81+/-1.11 microg/g (mid-region), 34.43+/-8.66 microg/g (closest to the plant) and 34.22+/-9.15 microg/g (directly downwind). Multiple regression analysis on log transformed MnH concentrations for the exposed children derived a model that explained 36.8% of the variability. In order of importance, area of children's residence, gender (girls>boys) and time of mother's residence in the area at the birth of the child, were significantly associated with MnH. Post hoc analyses indicated two groupings for exposure areas, with those living closest to and downwind of the plant displaying higher MnH concentrations compared to the others. The contribution of the time the mother lived in the community prior to the child's birth to the children's current MnH suggests that in utero exposure may play a role. A study of

  11. Manganese Exposure in the General Population in a Mining District ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Manganese Exposure in the General Population in a Mining District (Mexico) ... in a population living close to a mine and mineral processing plant in Mexico ... Call for proposals: Innovations for the economic inclusion of marginalized youth.

  12. Beneficiation studies of Bajaur manganese ore by different processing techniques

    International Nuclear Information System (INIS)

    Riaz, M.; Khan, F.U.; Yamin, A.; Bilquees, R.; Muhammad, N.

    2010-01-01

    The manganese ore of Bajaur Agency of Pakistan was subjected to flotation, heavy medium separation, gravity concentration and magnetic separation techniques for beneficiation. The original composition of the manganese ore was 45.56% Mn , 4% Fe/sub 2/O/sub 3/, 40% SiO/sub 2/. The Mn content was raised to a maximum 48.76 % in the concentrate with the recovery of 67.78 % through flotation technique. Other techniques rendered marginal increase in Mn concentration against the theoretical possibility of substantial enrichment by rejecting the 20 % gangue minerals. The separation of manganese minerals from associated gangue was difficult, due to mineralogical complexity of the ore, extreme fineness of the particle size, texture and minerals intergrowth. High Mn/Fe ratio, phosphorus, and silica contents were within tolerable limits for utilisation of the ore in ferro-manganese production. (author)

  13. By lithology Zbruch deposits (Lower Sarmatian Nikopol manganese ore Basin

    Directory of Open Access Journals (Sweden)

    Bogdanovich V.V.

    2010-06-01

    Full Text Available Based on lithologic-paleogeographic study Zbruch layers of Nikopol manganese ore Basin sediments described lithological and genetic types of rocks and facies conditions of formation of deposits.

  14. Manganese nodules in the Exclusive Economic Zone of Mauritius

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; ShyamPrasad, M.

    The distribution of manganese nodules in the Exclusive Economic Zone of the island nation Mauritius was delineated during cruise SK-35 of ORV Sagar Kanya in 1987. The areas surveyed included Saya de Malha and Nazareth Banks, the Cargados Carajos...

  15. Manganese oxidation by bacterial isolates from the Indian Ridge System

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, S.O.; Krishnan, K.P.; Khedekar, V.D.; LokaBharathi, P.A.

    The abundance and activity of culturable manganese-oxidizing bacteria were assessed from near-bottom water samples of the tectonically active Carlsberg Ridge. Retrievable counts as colony forming units (CFU) on dilute nutrient agar medium (dilNA = 2...

  16. Investigation of Wear Coefficient of Manganese Phosphate Coated Tool Steel

    Directory of Open Access Journals (Sweden)

    S. Ilaiyavel

    2013-03-01

    Full Text Available In recent years the properties of the coating in terms of wear resistance is of paramount importance in order to prevent the formation of severe damages. In this study, Wear coefficient of uncoated, Manganese Phosphate coated, Manganese Phosphate coated with oil lubricant, Heat treated Manganese Phosphate coated with oil lubricant on AISI D2 steels was investigated using Archard’s equation. The wear tests were performed in a pin on disk apparatus as per ASTM G-99 Standard. The volumetric wear loss and wear coefficient were evaluated through pin on disc test using a sliding velocity of 3.0 m/s under normal load of 40 N and controlled condition of temperature and humidity. Based on the results of the wear test, the Heat treated Manganese Phosphate with oil lubricant exhibited the lowest average wear coefficient and the lowest wear loss under 40 N load.

  17. Spectroscopic characterization of manganese-doped alkaline earth ...

    Indian Academy of Sciences (India)

    The shapes of spectra are also changed with varying alkaline earth ions content. ... of manganese ion and electrical properties of glass contain- ing mobile ions like .... octahedral crystal field are located above the ground 6S state. Figure 2.

  18. Arsenic, chromium, copper, iron, manganese, lead, selenium and ...

    African Journals Online (AJOL)

    Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the tissues of the largemouth yellowfish, Labeobarbus kimberleyensis (Gilchrist and Thompson, 1913), from the Vaal Dam, South Africa, and associated consumption risks.

  19. Production of manganese peroxidase by white rot fungi from potato ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-01-18

    Jan 18, 2010 ... production rate of the MnP using the potato-processing wastewater-based medium were higher (ca. 2.5- ... Ligninolytic enzymes, such as manganese peroxidase ... not currently reached industrial levels except for the laccase.

  20. Relation between grade and abundance of manganese nodules

    Digital Repository Service at National Institute of Oceanography (India)

    Sudhakar, M.

    Data from more than 1000 locations in the Central Indian Ocean Basin (CIOB) where both bulk nodule chemistry and abundance were determined and utilized to study the relationship between grade and abundance of manganese nodule deposits. Grade...

  1. India's manganese nodule mine site in the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Banakar, V.K.

    This commentary highlights the activities of massive exploration programme for manganese nodule deposits in the Central Indian Basin located 5 km below the ocean surface and India's claim for mine site development and registration with UNCLOS...

  2. Preparation of manganese-based perovskite nanoparticles using a ...

    Indian Academy of Sciences (India)

    Preparation of manganese-based perovskite nanoparticles using a reverse microemulsion method: ... ted much attention in various fields of medicine and pharma- cology such as .... In addition, the SAR value of sample was calculated through ...

  3. Anodically generated manganese(III) sulphate for the oxidation of ...

    Indian Academy of Sciences (India)

    Unknown

    oxidation of dipeptides in aqueous sulphuric acid medium: A kinetic study ... acetic acid (TFA) and N-methylmorpholine (NMM) were purchased ... and chloroform–methanol– acetic acid .... tion), manganese(II) sulphate and water (to keep the.

  4. Status and Role of Manganese in the Environment

    Directory of Open Access Journals (Sweden)

    RK Kamble

    2014-09-01

    Full Text Available Manganese is the second most abundant heavy metal, and in frequency list of elements it occupies 12th place. The Earth’s core contains about 1.5% manganese. According to Indian Standards for Drinking water (IS 10500:2012 manganese concentration in drinking water is 0.1 ppm (acceptable limit and 0.3 ppm as permissible limit. An attempt has been made to record the presence of manganese in different environmental matrices such as air, water, soil, food, its effects on plants, animals including human beings. DOI: http://dx.doi.org/10.3126/ije.v3i3.11081 International Journal of Environment Vol.3(3 2014: 222-234

  5. Investigation of manganese homeostasis in dogs with anaemia and ...

    African Journals Online (AJOL)

    Investigation of manganese homeostasis in dogs with anaemia and chronic enteropathy. Marisa da Fonseca Ferreira, Arielle Elizabeth Ann Aylor, Richard John Mellanby, Susan Mary Campbell, Adam George Gow ...

  6. Occupational neurotoxicology due to heavy metals-especially manganese poisoning

    International Nuclear Information System (INIS)

    Inoue, Naohide

    2007-01-01

    The most hazardous manganese exposures occur in mining and smelting of ore. Recently, the poisoning has been frequently reported to be associated with welding. In occupational exposure, manganese is absorbed mainly by inhalation. Manganese preferentially accumulates in tissues rich in mitochondria. It also penetrates the blood brain barrior and accumulate in the basal ganglia, especially the globus pallidus, but also the striatum. Manganese poisoning is clinically characterized by the central nervous system involvement including psychiatric symptomes, extrapyramidal signs, and less frequently other neurological manifestations. Psychiatric symptomes are well described in the manganese miners and incrude sleep disturbance, disorientation, emotional lability, compulsive acts, hallucinations, illusions, and delusions. The main characteristic manifestations usually begin shortly after the appearance of these psychiatric symptomes. The latter neurological signs are progressive bradykinesia, dystonia, and disturbance of gait. Bradykinesia is one of the most important findings. There is a remarkable slowing of both active and passive movements of the extremities. Micrographia is frequently observed and a characteristic finding. The patients may show some symmetrical tremor, which usually not so marked. The dystonic posture of the limbs is often accompanied by painfull cramps. This attitudal hypertonia has a tendency to decrease or disappear in the supine position and to increase in orthostation. Cog-wheel rigidity is also elisited on the passive movement of all extremities. Gait disturbance is also characteristic in this poisoning. In the severe cases, cook gait has been reported. The patient uses small steps, but has a tendency to elevate the heels and to rotate them outward. He progress without pressing on the flat of his feet, but only upon the metatarsophalangeal articulations, mainly of the fourth and fifth toes. Increased signal in T1-weighted image in the basal

  7. Aquatic environmental risk assessment of manganese processing industries.

    Science.gov (United States)

    Marks, Becky; Peters, Adam; McGough, Doreen

    2017-01-01

    An environmental risk assessment (ERA) has been conducted for sites producing and processing manganese and its inorganic compounds, focussing on potential risks to freshwater. A site specific questionnaire was used to collect information. Sites fall into three broad categories: mining sites, refining sites, and sites producing chemicals and pigments. Waste disposal is principally carried out by the treatment of liquid wastes to separate solids for disposal off-site with a consented wastewater discharge, or disposal on-site using evaporation or settlement ponds in order to maintain the waste materials in a suitable manner following site closure. The main source of emissions from refining and alloying sites is from the treatment of emissions to air using wet scrubber air filters. There is also the potential for fugitive environmental emissions of manganese from stockpiles of raw material held on-site. Data provided from the questionnaires were both site-specific and also commercially sensitive. Therefore, this paper has undertaken the manganese exposure assessment, using a probabilistic approach to reflect the distribution of emissions of manganese and also to maintain the confidentiality of site specific data. An inverse correlation was observed between the total annual tonnage of manganese processed at the site and the emission factor, such that sites processing larger quantities resulted in lower emissions of manganese per tonne processed. The hazard assessment determined a Predicted No Effect Concentration (PNEC) for freshwater using a species sensitivity distribution approach, resulting in a freshwater PNEC of 0.075mgL -1 for soluble manganese. Based on the exposure data and the freshwater PNEC derived for this study, the distributions of risk characterisation ratios using the probabilistic approach indicates that two thirds of manganese processing sites would not be expected to pose a potential risk to the local aquatic environment due to wastewater emissions

  8. Iron and manganese oxide mineralization in the Pacific

    Science.gov (United States)

    Hein, J. R.; Koschinsky, A.; Halbach, P.; Manheim, F. T.; Bau, M.; Jung-Keuk, Kang; Lubick, N.

    1997-01-01

    Iron, manganese, and iron-manganese deposits occur in nearly all geomorphologic and tectonic environments in the ocean basins and form by one or more of four processes: (1) hydrogenetic precipitation from cold ambient seawater, (2) precipitation from hydrothermal fluids, (3) precipitation from sediment pore waters that have been modified from bottom water compositions by diagenetic reactions in the sediment column and (4) replacement of rocks and sediment. These processes are discussed.

  9. Bioconcentration of manganese and iron in Panaeoloideae Sing

    OpenAIRE

    Stijve, T.; Blake, C.

    1994-01-01

    According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae, as demonstrated by the analysis of 44 collections representing 15 taxons. Carpophores generally contain between 250 and 2500 mg/kg on dry weight, and, with the notable exception of Panaeolus semiova...

  10. Miniature EVA Software Defined Radio

    Science.gov (United States)

    Pozhidaev, Aleksey

    2012-01-01

    As NASA embarks upon developing the Next-Generation Extra Vehicular Activity (EVA) Radio for deep space exploration, the demands on EVA battery life will substantially increase. The number of modes and frequency bands required will continue to grow in order to enable efficient and complex multi-mode operations including communications, navigation, and tracking applications. Whether conducting astronaut excursions, communicating to soldiers, or first responders responding to emergency hazards, NASA has developed an innovative, affordable, miniaturized, power-efficient software defined radio that offers unprecedented power-efficient flexibility. This lightweight, programmable, S-band, multi-service, frequency- agile EVA software defined radio (SDR) supports data, telemetry, voice, and both standard and high-definition video. Features include a modular design, an easily scalable architecture, and the EVA SDR allows for both stationary and mobile battery powered handheld operations. Currently, the radio is equipped with an S-band RF section. However, its scalable architecture can accommodate multiple RF sections simultaneously to cover multiple frequency bands. The EVA SDR also supports multiple network protocols. It currently implements a Hybrid Mesh Network based on the 802.11s open standard protocol. The radio targets RF channel data rates up to 20 Mbps and can be equipped with a real-time operating system (RTOS) that can be switched off for power-aware applications. The EVA SDR's modular design permits implementation of the same hardware at all Network Nodes concept. This approach assures the portability of the same software into any radio in the system. It also brings several benefits to the entire system including reducing system maintenance, system complexity, and development cost.

  11. Defining Game Mechanics

    DEFF Research Database (Denmark)

    Sicart (Vila), Miguel Angel

    2008-01-01

    This article defins game mechanics in relation to rules and challenges. Game mechanics are methods invoked by agents for interacting with the game world. I apply this definition to a comparative analysis of the games Rez, Every Extend Extra and Shadow of the Colossus that will show the relevance...... of a formal definition of game mechanics. Udgivelsesdato: Dec 2008...

  12. Modal Logics and Definability

    OpenAIRE

    Kuusisto, Antti

    2013-01-01

    In recent years, research into the mathematical foundations of modal logic has become increasingly popular. One of the main reasons for this is the fact that modal logic seems to adapt well to the requirements of a wide range of different fields of application. This paper is a summary of some of the author’s contributions to the understanding of modal definability theory.

  13. Software Defined Cyberinfrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Foster, Ian; Blaiszik, Ben; Chard, Kyle; Chard, Ryan

    2017-07-17

    Within and across thousands of science labs, researchers and students struggle to manage data produced in experiments, simulations, and analyses. Largely manual research data lifecycle management processes mean that much time is wasted, research results are often irreproducible, and data sharing and reuse remain rare. In response, we propose a new approach to data lifecycle management in which researchers are empowered to define the actions to be performed at individual storage systems when data are created or modified: actions such as analysis, transformation, copying, and publication. We term this approach software-defined cyberinfrastructure because users can implement powerful data management policies by deploying rules to local storage systems, much as software-defined networking allows users to configure networks by deploying rules to switches.We argue that this approach can enable a new class of responsive distributed storage infrastructure that will accelerate research innovation by allowing any researcher to associate data workflows with data sources, whether local or remote, for such purposes as data ingest, characterization, indexing, and sharing. We report on early experiments with this approach in the context of experimental science, in which a simple if-trigger-then-action (IFTA) notation is used to define rules.

  14. Defining Abnormally Low Tenders

    DEFF Research Database (Denmark)

    Ølykke, Grith Skovgaard; Nyström, Johan

    2017-01-01

    The concept of an abnormally low tender is not defined in EU public procurement law. This article takes an interdisciplinary law and economics approach to examine a dataset consisting of Swedish and Danish judgments and verdicts concerning the concept of an abnormally low tender. The purpose...

  15. Software Defined Coded Networking

    DEFF Research Database (Denmark)

    Di Paola, Carla; Roetter, Daniel Enrique Lucani; Palazzo, Sergio

    2017-01-01

    the quality of each link and even across neighbouring links and using simulations to show that an additional reduction of packet transmission in the order of 40% is possible. Second, to advocate for the use of network coding (NC) jointly with software defined networking (SDN) providing an implementation...

  16. Defining and classifying syncope

    NARCIS (Netherlands)

    Thijs, Roland D.; Wieling, Wouter; Kaufmann, Horacio; van Dijk, Gert

    2004-01-01

    There is no widely adopted definition or classification of syncope and related disorders. This lack of uniformity harms patient care, research, and medical education. In this article, syncope is defined as a form of transient loss of consciousness (TLOC) due to cerebral hypoperfusion. Differences

  17. Relationship between blood manganese and blood pressure in the Korean general population according to KNHANES 2008

    International Nuclear Information System (INIS)

    Lee, Byung-Kook; Kim, Yangho

    2011-01-01

    Introduction: We present data on the association of manganese (Mn) level with hypertension in a representative sample of the adult Korean population who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) 2008. Methods: This study was based on the data obtained by KNHANES 2008, which was conducted for three years (2007-2009) using a rolling sampling design involving a complex, stratified, multistage, probability-cluster survey of a representative sample of the noninstitutionalized civilian population of South Korea. Results: Multiple regression analysis after controlling for covariates, including gender, age, regional area, education level, smoking, drinking status, hemoglobin, and serum creatinine, showed that the beta coefficients of log blood Mn were 3.514, 1.878, and 2.517 for diastolic blood pressure, and 3.593, 2.449, and 2.440 for systolic blood pressure in female, male, and all participants, respectively. Multiple regression analysis including three other blood metals, lead, mercury, and cadmium, revealed no significant effects of the three metals on blood pressure and showed no effect on the association between blood Mn and blood pressure. In addition, doubling the blood Mn increased the risk of hypertension 1.828, 1.573, and 1.567 fold in women, men, and all participants, respectively, after adjustment for covariates. The addition of blood lead, mercury, and cadmium as covariates did not affect the association between blood Mn and the prevalence of hypertension. Conclusion: Blood Mn level was associated with an increased risk of hypertension in a representative sample of the Korean adult population. - Highlights: → We showed the association of manganese with hypertension in Korean population. → This study was based on the data obtained by KNHANES 2008. → Blood manganese level was associated with an increased risk of hypertension.

  18. Low copper and high manganese levels in prion protein plaques

    Science.gov (United States)

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  19. Permanganate-based synthesis of manganese oxide nanoparticles in ferritin

    Science.gov (United States)

    Olsen, Cameron R.; Smith, Trevor J.; Embley, Jacob S.; Maxfield, Jake H.; Hansen, Kameron R.; Peterson, J. Ryan; Henrichsen, Andrew M.; Erickson, Stephen D.; Buck, David C.; Colton, John S.; Watt, Richard K.

    2017-05-01

    This paper investigates the comproportionation reaction of MnII with {{{{MnO}}}4}- as a route for manganese oxide nanoparticle synthesis in the protein ferritin. We report that {{{{MnO}}}4}- serves as the electron acceptor and reacts with MnII in the presence of apoferritin to form manganese oxide cores inside the protein shell. Manganese loading into ferritin was studied under acidic, neutral, and basic conditions and the ratios of MnII and permanganate were varied at each pH. The manganese-containing ferritin samples were characterized by transmission electron microscopy, UV/Vis absorption, and by measuring the band gap energies for each sample. Manganese cores were deposited inside ferritin under both the acidic and basic conditions. All resulting manganese ferritin samples were found to be indirect band gap materials with band gap energies ranging from 1.01 to 1.34 eV. An increased UV/Vis absorption around 370 nm was observed for samples formed under acidic conditions, suggestive of MnO2 formation inside ferritin.

  20. Spatial and temporal variations of manganese concentrations in drinking water.

    Science.gov (United States)

    Barbeau, Benoit; Carrière, Annie; Bouchard, Maryse F

    2011-01-01

    The objective of this study was to assess the variability of manganese concentrations in drinking water (daily, seasonal, spatial) for eight communities who participated in an epidemiological study on neurotoxic effects associated with exposure to manganese in drinking water. We also assessed the performance of residential point-of-use and point-of-entry devices (POE) for reducing manganese concentrations in water. While the total Mn concentrations measured during this study were highly variable depending on the location (manganese concentration for 4 out of 5 sampling locations. The efficiency of reverse osmosis and ion exchange for total Mn removal was consistently high while activated carbon provided variable results. The four POE greensand filters investigated all increased (29 to 199%) manganese concentration, indicating deficient operation and/or maintenance practices. Manganese concentrations in the distribution system were equal or lower than at the inlet, indicating that sampling at the inlet of the distribution system is conservative. The decline in total Mn concentration was linked to higher water residence time in the distribution system.

  1. Failure of manganese to protect from Shiga toxin.

    Directory of Open Access Journals (Sweden)

    Marsha A Gaston

    Full Text Available Shiga toxin (Stx, the main virulence factor of Shiga toxin producing Escherichia coli, is a major public health threat, causing hemorrhagic colitis and hemolytic uremic syndrome. Currently, there are no approved therapeutics for these infections; however manganese has been reported to provide protection from the Stx1 variant isolated from Shigella dysenteriae (Stx1-S both in vitro and in vivo. We investigated the efficacy of manganese protection from Stx1-S and the more potent Stx2a isoform, using experimental systems well-established for studying Stx: in vitro responses of Vero monkey kidney cells, and in vivo toxicity to CD-1 outbred mice. Manganese treatment at the reported therapeutic concentration was toxic to Vero cells in culture and to CD-1 mice. At lower manganese concentrations that were better tolerated, we observed no protection from Stx1-S or Stx2a toxicity. The ability of manganese to prevent the effects of Stx may be particular to certain cell lines, mouse strains, or may only be manifested at high, potentially toxic manganese concentrations.

  2. Alterações encontradas no potencial visual evocado por padrão reverso em pacientes com esclerose múltipla definida Pattern-reversal visual evoked potential abnormalities in patients with defined multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Eric Pinheiro de Andrade

    2007-12-01

    Full Text Available INTRODUÇÃO: Esclerose múltipla é uma doença desmielinizante idiopática, podendo acometer o nervo óptico com perda visual unilateral aguda que pode ser observada através do potencial visual evocado (PVE, definindo tal exame como de grande validade para o estudo pré-quiasmático das vias visuais na esclerose múltipla. OBJETIVO: Analisar os achados dos potenciais visuais evocados por reversão de padrões em pacientes com diagnóstico prévio de esclerose múltipla e sua comparação com a acuidade visual. MÉTODOS: Vinte e quatro pacientes com diagnóstico definido de esclerose múltipla foram submetidos ao PVE por reversão de padrões no período de outubro de 2001 a março de 2007. RESULTADOS: Na resposta do componente P100, nos estímulos de 15' e 1º, se observou que 19 olhos apresentaram resposta de latência até 115 ms em ambas as estimulações, coincidindo também em 6 olhos que apresentaram resposta de latência entre 116 a 135 ms, em 11 olhos que apresentaram resposta de latências superiores a 135 ms, e em 4 olhos que não apresentaram respostas às estimulações. Correlacionando a acuidade visual com a latência de P100 para 15', obtemos na correlação de Pearson r= 0,85 com p= 0,000000123, e para 1º, r= 0,87 com p= 0,0000000338. CONCLUSÃO: Aproximadamente 60,4% dos pacientes apresentaram anormalidades no PVE por padrões reversos. Contudo, a correlação entre a latência de P100 (15' e 1º e a acuidade visual foi estatisticamente significativa, assim sendo, quanto melhor a acuidade visual, melhor será sua resposta aos estímulos do PVE por reversão de padrões.INTRODUCTION: Multiple sclerosis is an idiopathic demyelinating disease that may affect the optic nerve leading to acute unilateral visual loss, which could be observed by means of evoked visual potential (VEP. This exam is much valued for studying prechiasmatic visual paths in multiple sclerosis. PURPOSE: To analyze the findings of pattern reversal VEP in

  3. Defining Legal Moralism

    DEFF Research Database (Denmark)

    Thaysen, Jens Damgaard

    2015-01-01

    This paper discusses how legal moralism should be defined. It is argued that legal moralism should be defined as the position that “For any X, it is always a pro tanto reason for justifiably imposing legal regulation on X that X is morally wrong (where “morally wrong” is not conceptually equivalent...... to “harmful”)”. Furthermore, a distinction between six types of legal moralism is made. The six types are grouped according to whether they are concerned with the enforcement of positive or critical morality, and whether they are concerned with criminalising, legally restricting, or refraining from legally...... protecting morally wrong behaviour. This is interesting because not all types of legal moralism are equally vulnerable to the different critiques of legal moralism that have been put forth. Indeed, I show that some interesting types of legal moralism have not been criticised at all....

  4. Defining local food

    DEFF Research Database (Denmark)

    Eriksen, Safania Normann

    2013-01-01

    Despite evolving local food research, there is no consistent definition of “local food.” Various understandings are utilized, which have resulted in a diverse landscape of meaning. The main purpose of this paper is to examine how researchers within the local food systems literature define local...... food, and how these definitions can be used as a starting point to identify a new taxonomy of local food based on three domains of proximity....

  5. Restoration of growth by manganese in a mutant strain of Escherichia coli lacking most known iron and manganese uptake systems

    DEFF Research Database (Denmark)

    Taudte, Nadine; German, Nadezhda; Zhu, Yong-Guan

    2016-01-01

    The interplay of manganese and iron homeostasis and oxidative stress in Escherichia coli can give important insights into survival of bacteria in the phagosome and under differing iron or manganese bioavailabilities. Here, we characterized a mutant strain devoid of all know iron/manganese-uptake ......The interplay of manganese and iron homeostasis and oxidative stress in Escherichia coli can give important insights into survival of bacteria in the phagosome and under differing iron or manganese bioavailabilities. Here, we characterized a mutant strain devoid of all know iron...

  6. Manganese substitutions into the portland cement clinker phases

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    1989-06-01

    Full Text Available The effect of manganese substitution into the crystal structures of the main Portland cement clinker phases (3CaO.SiO2, 2CaO.SiO2, 3CaO.Al2O3, 2CaO.Fe2O3 y 4CaO.Al2O3.Fe2O3 has been studied by X-ray and analytical electron microscopy. In oxidizing conditions, the limit of solid solution in 3CaO.SiO2 is about 0.72 ±0.11% (wt, while in 2CaO.SiO2 is 1.53±0,12%(wt. Mn solid solubility on 3CaO.Al2O3structure, in oxidizing conditions is close to 0.78 ± 0,12% (wt. In identical atmosphere, the proportion of Mn in the ferrite phases (2CaO.Fe2O3 and 4CaO.Al2O3.Fe2O3 is 6.80 ± 0.87% (wt and 6.7% (wt, respectively. To each mentioned clinker phases a solid solution formula has been proposed. In these formula, the manganese substitutions and also the different oxidation states which this element can be introduced in those crystalline structure are defined.

    Se ha estudiado, por difracción de rayos X y microanálisis por espectroscopia de energías dispersivas, el efecto de la sustitución del manganeso en las estructuras cristalinas de las fases más importantes del clinker del cemento portland (3CaO.SiO2, 2CaO.SiO2, 3CaO.Al2O3, 2CaO.Fe2O3 y 4CaO.Al2O3.Fe2O3. En condiciones oxidantes, el límite de solubilidad sólida en 3CaO.SiO2 es del orden de 0,72 ± 0,11% en peso; mientras que en 2CaO.SiO2 es de 1,53 ±0,12% en peso. La solución sólida del Mn en la estructura del 3CaO.Al2O3, en condiciones oxidantes, es próxima al 0,78 ±0,12% en peso. En idéntica atmósfera, la proporción del Mn en las fases terríficas (2CaO.Fe2O3 y 4CaO.Al2

  7. Submicron Features in Higher Manganese Silicide

    Directory of Open Access Journals (Sweden)

    Yatir Sadia

    2013-01-01

    Full Text Available The world energy crisis had increased the demand for alternative energy sources and as such is one of the topics at the forefront of research. One way for reducing energy consumption is by thermoelectricity. Thermoelectric effects enable direct conversion of thermal into electrical energy. Higher manganese silicide (HMS, MnSi1.75 is one of the promising materials for applications in the field of thermoelectricity. The abundance and low cost of the elements, combined with good thermoelectric properties and high mechanical and chemical stability at high temperatures, make it very attractive for thermoelectric applications. Recent studies have shown that Si-rich HMS has improved thermoelectric properties. The most interesting of which is the unusual reduction in thermal conductivity. In the current research, transmission (TEM and scanning (SEM electron microscopy as well as X-ray diffraction methods were applied for investigation of the govern mechanisms resulting in very low thermal conductivity values of an Si-rich HMS composition, following arc melting and hot-pressing procedures. In this paper, it is shown that there is a presence of sub-micron dislocations walls, stacking faults, and silicon and HMS precipitates inside each other apparent in the matrix, following a high temperature (0.9 Tm hot pressing for an hour. These are not just responsible for the low thermal conductivity values observed but also indicate the ability to create complicate nano-structures that will last during the production process and possibly during the application.

  8. Low carbon manganese-nickel-niobium steel

    International Nuclear Information System (INIS)

    Heisterkamp, F.; Hulka, K.

    1983-11-01

    Experimental heats of a low carbon-manganese-0.5% nickel-0.15% niobium steel have been rolled to plates between 13.5 and 50 mm thickness and to a 16 mm hot strip. Various combinations of soaking temperatures form 1100 0 C to 1300 0 C and of finish rolling temperatures between 710 0 C and 930 0 C have been investigated. From mechanical properties obtained, one can conclude that the investigated steel composition provides very good properties e.g. for pipe steels X65 to X75. In particular, the toughness at low temperature is outstanding despite relaxed rolling conditions. Metalographic and special investigations such as electron microscopy, texture evaluation and chemical extraction, correlated with applied rolling schedules and the mechanical properties obtained resulted in a comprehensive understanding about the benefits of high niobium metallurgy combined with nickel addition. All practically applied welding processes generated mechanical properties, in particular toughness of the weldment, that meet arctic specifications.(Author) [pt

  9. Manganese Superoxide Dismutase: Guardian of the Powerhouse

    Directory of Open Access Journals (Sweden)

    Daret K. St. Clair

    2011-10-01

    Full Text Available The mitochondrion is vital for many metabolic pathways in the cell, contributing all or important constituent enzymes for diverse functions such as β-oxidation of fatty acids, the urea cycle, the citric acid cycle, and ATP synthesis. The mitochondrion is also a major site of reactive oxygen species (ROS production in the cell. Aberrant production of mitochondrial ROS can have dramatic effects on cellular function, in part, due to oxidative modification of key metabolic proteins localized in the mitochondrion. The cell is equipped with myriad antioxidant enzyme systems to combat deleterious ROS production in mitochondria, with the mitochondrial antioxidant enzyme manganese superoxide dismutase (MnSOD acting as the chief ROS scavenging enzyme in the cell. Factors that affect the expression and/or the activity of MnSOD, resulting in diminished antioxidant capacity of the cell, can have extraordinary consequences on the overall health of the cell by altering mitochondrial metabolic function, leading to the development and progression of numerous diseases. A better understanding of the mechanisms by which MnSOD protects cells from the harmful effects of overproduction of ROS, in particular, the effects of ROS on mitochondrial metabolic enzymes, may contribute to the development of novel treatments for various diseases in which ROS are an important component.

  10. Environmental Exposure to Manganese in Air: Associations ...

    Science.gov (United States)

    Manganese (Mn), an essential element, can be neurotoxic in high doses. This cross-sectional study explored the oognitive function of adults residing in two towns (Marietta and East Liverpool, Ohio, USA) identified as having high levels of environmental airborne Mn from industrial sources. Air-Mn site surface emissions method modeling for total suspended particulate (TSP) ranged from 0.03 to 1.61 µg/m(3) in Marietta and 0.01-6.32 µg/m(3) in East Liverpool. A comprehensive screening test battery of cognitive function, including the domains of abstract thinking, attention/concentration, executive function and memory was administered. The mean age of the participants was 56 years (±10.8 years). Participants were mostly female (59.1) and primarily white (94.6%). Significant relationships (pworking and visuospatial memory (e.g., Rey-0 Immediate B3=0.19, Rey-0 Delayed B3=0.16) and verbal skills (e.g., Similarities B3=0.19). Using extensive cognitive testing and computer modeling of 10-plus years of measured air monitoring data, this study suggests that long-term environmental exposure to high levels of air-Mn, the exposure metric of this paper, may result in mild deficits of cognitive function in adult populations. This study addresses research questions under Sustainable and Healthy Communities (2.2.1.6 lessons learned, best practices and stakeholder feedback from community and tribal participa

  11. Manganese Dioxide As Rechargeable Magnesium Battery Cathode

    International Nuclear Information System (INIS)

    Ling, Chen; Zhang, Ruigang

    2017-01-01

    Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg 2+ -intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO 2 in magnesium cells. In recent years, the cathodic performance of MnO 2 was impressively improved to the capacity of >150–200 mAh g −1 at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO 2 cathode has been changed and how it paved the road to the improvement of cathode performance.

  12. Manganese Dioxide As Rechargeable Magnesium Battery Cathode

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Chen, E-mail: chen.ling@toyota.com; Zhang, Ruigang [Toyota Research Institute of North America, Ann Arbor, MI (United States)

    2017-11-03

    Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg{sup 2+}-intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO{sub 2} in magnesium cells. In recent years, the cathodic performance of MnO{sub 2} was impressively improved to the capacity of >150–200 mAh g{sup −1} at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO{sub 2} cathode has been changed and how it paved the road to the improvement of cathode performance.

  13. Alternative method of portable irradiation of manganese sulphate solution by an plutonium-beryllium source for manganese sulphate bath efficiency measurements; Metodo alternativo de irradiacao portatil da solucao de sulfato de manganes por uma fonte de plutonio-berilio para medicoes de eficiencia do banho de sulfato de manganes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner, E-mail: fellipess@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO{sub 4} solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  14. Methylphenidate alleviates manganese-induced impulsivity but not distractibility

    Science.gov (United States)

    Beaudin, Stephane A.; Strupp, Barbara J.; Uribe, Walter; Ysais, Lauren; Strawderman, Myla; Smith, Donald R.

    2017-01-01

    Recent studies from our lab have demonstrated that postnatal manganese (Mn) exposure in a rodent model can cause lasting impairments in fine motor control and attention, and that oral methylphenidate (MPH) treatment can effectively treat the dysfunction in fine motor control. However, it is unknown whether MPH treatment can alleviate the impairments in attention produced by Mn exposure. Here we used a rodent model of postnatal Mn exposure to determine whether (1) oral MPH alleviates attention and impulse control deficits caused by postnatal Mn exposure, using attention tasks that are variants of the 5-choice serial reaction time task, and (2) whether these treatments affected neuronal dendritic spine density in the medial prefrontal cortex (mPFC) and dorsal striatum. Male Long-Evans rats were exposed orally to 0 or 50 mg Mn/kg/d throughout life starting on PND 1, and tested as young adults (PND 107 – 115) on an attention task that specifically tapped selective attention and impulse control. Animals were treated with oral MPH (2.5 mg/kg/d) throughout testing on the attention task. Our findings show that lifelong postnatal Mn exposure impaired impulse control and selective attention in young adulthood, and that a therapeutically relevant oral MPH regimen alleviated the Mn-induced dysfunction in impulse control, but not selective attention, and actually impaired focused attention in the Mn group. In addition, the effect of MPH was qualitatively different for the Mn-exposed versus control animals across a range of behavioral measures of inhibitory control and attention, as well as dendritic spine density in the mPFC, suggesting that postnatal Mn exposure alters catecholaminergic systems modulating these behaviors. Collectively these findings suggest that MPH may hold promise for treating the behavioral dysfunction caused by developmental Mn exposure, although further research is needed with multiple MPH doses to determine whether a dose can be identified that

  15. Anormalidades do potencial evocado visual por padrão reverso em pacientes com esclerose múltipla definida Pattern reversal visual evoked potential abnormalities in patients with defined multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Vítor Tumas

    1995-12-01

    Full Text Available O potencial evocado visual por padrão reverso, obtido por padrões de 14' e 28', foi analisado retrospectivamente em 28 pacientes com diagnóstico de esclerose múltipla definida. Observamos respostas anormais em 27/28 (96,4% pacientes, em 31/36 (86% dos olhos considerados sintomáticos e em 16/20 (80% dos ollhos assintomáticos. Classificando os achados em cada olho segundo as respostas obtidas aos dois estímulos, observamos uma possível relação entre essa classificação e a gravidade de comprometimento visual pela doença. Detectamos em alguns olhos anormalidades isoladas do N75 e também de P100 apenas à estimulação de 28'. Dessa forma, a técnica empregada foi considerada sensível e pôde definir inclusive comprometimento visual subclínico. Entretanto, não teve sensibilidade absoluta para detectar anormalidades em alguns olhos sintomáticos. O tipo de resposta aos estímulos empregados pode sugerir o grau de extensão de envolvimento do sistema visual pela doença. Os achados mostram ainda o envolvimento irregular e predominante das fibras mais centrais da visão pela esclerose múltipla, e sugerem processadores neurais distintos e paralelos para as respostas aos dois padrões utilizados.The pattern reversal visual evoked potential with checks of 14' and 28' was restropectivelly studied in 28 patients with definite multiple sclerosis. We observed abnormal responses in 27/28 (96.4% patients, in 31/36 (86% of symptomatic eyes, and in 16/20 (80% of asymptomatic eyes. When we classified the abnormalities in each eye according to the findings obtained with each check, there was a correlation between the pattern of abnormalities and the severity of visual involvement. Occasionally there were isolated abnormalities of N75 or only in P100 obtained with 28' checks. In conclusion the methodology applied was very sensible in detecting abnormalities in visual pathway. We could classify the findings in each eye and correlate them with the

  16. Defining product service systems

    DEFF Research Database (Denmark)

    McAloone, Timothy Charles; Andreasen, Mogens Myrup

    2002-01-01

    , company and society benefit from the service systems related to each one of these dimensions, rather than simply one of the above. There are existing examples of the enhancement of business and market share by focusing on PSS, but this is often not a result of upfront strategy and ambitious goals. We...... attempt to identify the nature of such a multiple definition of PSS, the link to proper understanding of value and utility and innovative approaches for PSS-oriented product development. This paper will expand on the phenomenon of PSS in the belief that a proper understanding of PSS will give us...

  17. Mercury distribution characteristics in primary manganese smelting plants

    International Nuclear Information System (INIS)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-01-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1–99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. - Graphical abstract: 1. Lack of data on mercury (Hg) distribution in manganese smelters. 2. Mass distribution of Hg released from 3 plants (as normalized values) were made as follows by measurements. 3. Information of distribution of Hg in Manganese smelters would be used for emission in to air and releases to other streams for the nation and globe in UNEP mercury report. - Highlights: • The mass balance study by on-site measurement from primary manganese smelting plants was made at first time in the world. • Hg distribution and main input and release pathways of Hg from primary manganese smelting plants could be found as the first time. • Gas temperature in bag filter affects Hg behavior and speciation changes in APCDs. • National inventory of Hg emssion has been updated with new data. - Mercury distribution in manganese smelting plant was investigated as the first measurements at commercial plants in the world. National Hg release

  18. Quantification of manganese in human hand bones: a feasibility study

    International Nuclear Information System (INIS)

    Aslam; Pejovic-Milic, A; Chettle, D R; McNeill, F E

    2008-01-01

    Manganese is both an essential element to human health and also toxic when humans are exposed to excessive levels, particularly by means of inhalation. Biological monitoring of manganese exposure is problematic. It is subject to homeostasis; levels in blood (or serum/plasma) reflect only the most recent exposure and rapidly return to within normal ranges, even when there has been a temporary excursion in response to exposure. In this context, we have been developing a non-invasive technique for measurement of manganese stored in bone, using in vivo neutron activation analysis. Following preliminary feasibility studies, the technique has been enhanced by two significant infrastructure advances. A specially designed irradiation facility serves to maximize the activation of manganese with respect to the dose of ionizing radiation. Secondly, an array of eight NaI(Tl) crystals provides a detection system with very close to 4π geometry. This feasibility study, using neutron activation analysis to measure manganese in the bones of the hand, takes two features into account. Firstly, there is considerable magnesium present in the bone and this produces a spectral interference with the manganese. The 26 Mg(n,γ) 27 Mg reaction produces γ-rays of 0.843 MeV from the decay of 27 Mg, which interfere with the 0.847 MeV γ-rays from the decay of 56 Mn, produced by the 55 Mn(n,γ) 56 Mn reaction. Secondly, this work provides estimates of the levels of manganese to be expected in referent subjects. A revised estimate has been made from the most recent literature to explore the potential of the technique as a suitable means of screening patients and people exposed to excessive amounts of Mn who could develop many-fold increased levels of Mn in bones as demonstrated through various animal studies. This report presents the enhancements to the neutron activation system, by which manganese can be measured, which resulted in a detection limit in the hand of human subjects of 1.6

  19. Quantification of manganese in human hand bones: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Aslam; Pejovic-Milic, A; Chettle, D R; McNeill, F E [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, L8S 4K1 (Canada)], E-mail: aslamib@mcmaster.ca

    2008-08-07

    Manganese is both an essential element to human health and also toxic when humans are exposed to excessive levels, particularly by means of inhalation. Biological monitoring of manganese exposure is problematic. It is subject to homeostasis; levels in blood (or serum/plasma) reflect only the most recent exposure and rapidly return to within normal ranges, even when there has been a temporary excursion in response to exposure. In this context, we have been developing a non-invasive technique for measurement of manganese stored in bone, using in vivo neutron activation analysis. Following preliminary feasibility studies, the technique has been enhanced by two significant infrastructure advances. A specially designed irradiation facility serves to maximize the activation of manganese with respect to the dose of ionizing radiation. Secondly, an array of eight NaI(Tl) crystals provides a detection system with very close to 4{pi} geometry. This feasibility study, using neutron activation analysis to measure manganese in the bones of the hand, takes two features into account. Firstly, there is considerable magnesium present in the bone and this produces a spectral interference with the manganese. The {sup 26}Mg(n,{gamma}){sup 27}Mg reaction produces {gamma}-rays of 0.843 MeV from the decay of {sup 27}Mg, which interfere with the 0.847 MeV {gamma}-rays from the decay of {sup 56}Mn, produced by the {sup 55}Mn(n,{gamma}){sup 56}Mn reaction. Secondly, this work provides estimates of the levels of manganese to be expected in referent subjects. A revised estimate has been made from the most recent literature to explore the potential of the technique as a suitable means of screening patients and people exposed to excessive amounts of Mn who could develop many-fold increased levels of Mn in bones as demonstrated through various animal studies. This report presents the enhancements to the neutron activation system, by which manganese can be measured, which resulted in a detection

  20. Manganese and acute paranoid psychosis: a case report

    Directory of Open Access Journals (Sweden)

    Egger Jos I

    2011-04-01

    Full Text Available Abstract Introduction Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional instability. Later, several organ systems may be affected and, due to neurotoxicity, an atypical parkinsonian syndrome may emerge. With regard to neuropsychiatry, an array of symptoms may develop up to 30 years after intoxication, of which gait and speech abnormalities, cognitive and motor slowing, mood changes and hallucinations are the most common. Psychotic phenomena are rarely reported. Case presentation We describe the case of a 49-year-old Caucasian man working as a welder who was referred to our facility for evaluation of acute paranoid psychotic behavior. Our patient's medical history made no mention of any somatic complaints or psychiatric symptoms, and he had been involved in a professional career as a metalworker. On magnetic resonance imaging scanning of his brain, a bilateral hyperdensity of the globus pallidus, suggestive for manganese intoxication, was found. His manganese serum level was 52 to 97 nmol/L (range: 7 to 20 nmol/L. A diagnosis of organic psychotic disorder due to manganese overexposure was made. His psychotic symptoms disappeared within two weeks of treatment with low-dose risperidone. At three months later, serum manganese was decreased to slightly elevated levels and the magnetic resonance imaging T1 signal intensity was reduced. No signs of Parkinsonism were found and a definite diagnosis of manganese-induced apathy syndrome was made. Conclusion Although neuropsychiatric and neurological symptoms caused by (chronic manganese exposure have been reported frequently in the past, in the present day the disorder is rarely diagnosed. In this report we stress that manganese intoxication can still occur, in our case in a confined

  1. Mutation in HFE gene decreases manganese accumulation and oxidative stress in the brain after olfactory manganese exposure.

    Science.gov (United States)

    Ye, Qi; Kim, Jonghan

    2016-06-01

    Increased accumulation of manganese (Mn) in the brain is significantly associated with neurobehavioral deficits and impaired brain function. Airborne Mn has a high systemic bioavailability and can be directly taken up into the brain, making it highly neurotoxic. While Mn transport is in part mediated by several iron transporters, the expression of these transporters is altered by the iron regulatory gene, HFE. Mutations in the HFE gene are the major cause of the iron overload disorder, hereditary hemochromatosis, one of the prevalent genetic diseases in humans. However, whether or not HFE mutation modifies Mn-induced neurotoxicity has not been evaluated. Therefore, our goal was to define the role of HFE mutation in Mn deposition in the brain and the resultant neurotoxic effects after olfactory Mn exposure. Mice carrying the H67D HFE mutation, which is homologous to the H63D mutation in humans, and their control, wild-type mice, were intranasally instilled with MnCl2 with different doses (0, 0.2, 1.0 and 5.0 mg kg(-1)) daily for 3 days. Mn levels in the blood, liver and brain were determined using inductively-coupled plasma mass spectrometry (ICP-MS). H67D mutant mice showed significantly lower Mn levels in the blood, liver, and most brain regions, especially in the striatum, while mice fed an iron-overload diet did not. Moreover, mRNA expression of ferroportin, an essential exporter of iron and Mn, was up-regulated in the striatum. In addition, the levels of isoprostane, a marker of lipid peroxidation, were increased in the striatum after Mn exposure in wild-type mice, but were unchanged in H67D mice. Together, our results suggest that the H67D mutation provides decreased susceptibility to Mn accumulation in the brain and neurotoxicity induced by inhaled Mn.

  2. Manganese and iron oxidation by fungi isolated from building stone.

    Science.gov (United States)

    de la Torre, M A; Gomez-Alarcon, G

    1994-01-01

    Acid and nonacid generating fungal strains isolated from weathered sandstone, limestone, and granite of Spanish cathedrals were assayed for their ability to oxidize iron and manganese. In general, the concentration of the different cations present in the mineral salt media directly affected Mn(IV) oxide formation, although in some cases, the addition of glucose and nitrate to the culture media was necessary. Mn(II) oxidation in acidogenic strains was greater in a medium containing the highest concentrations of glucose, nitrate, and manganese. High concentrations of Fe(II), glucose, and mineral salts were optimal for iron oxidation. Mn(IV) precipitated as oxides or hydroxides adhered to the mycelium. Most of the Fe(III) remained in solution by chelation with organic acids excreted by acidogenic strains. Other metabolites acted as Fe(III) chelators in nonacidogenic strains, although Fe(III) deposits around the mycelium were also detected. Both iron and manganese oxidation were shown to involve extracellular, hydrosoluble enzymes, with maximum specific activities during exponential growth. Strains able to oxidize manganese were also able to oxidize iron. It is concluded that iron and manganese oxidation reported in this work were biologically induced by filamentous fungi mainly by direct (enzymatic) mechanisms.

  3. [Factors affecting biological removal of iron and manganese in groundwater].

    Science.gov (United States)

    Xue, Gang; He, Sheng-Bing; Wang, Xin-Ze

    2006-01-01

    Factors affecting biological process for removing iron and manganese in groundwater were analyzed. When DO and pH in groundwater after aeration were 7.0 - 7.5 mg/L and 6.8 - 7.0 respectively, not only can the activation of Mn2+ oxidizing bacteria be maintained, but also the demand of iron and manganese removal can be satisfied. A novel inoculating approach of grafting mature filter material into filter bed, which is easier to handle than selective culture media, was employed in this research. However, this approach was only suitable to the filter material of high-quality manganese sand with strong Mn2+ adsorption capacity. For the filter material of quartz sand with weak adsorption capacity, only culturing and domesticating Mn2+ oxidizing bacteria by selective culture media can be adopted as inoculation in filter bed. The optimal backwashing rate of biological filter bed filled with manganese sand and quartz sand should be kept at a relatively low level of 6 - 9 L/(m2 x s) and 7 -11 L/( m2 x s), respectively. Then the stability of microbial phase in filter bed was not disturbed, and iron and manganese removal efficiency recovered in less than 5h. Moreover, by using filter material with uniform particle size of 1.0 - 1.2 mm in filter bed, the filtration cycle reached as long as 35 - 38h.

  4. The sorption of silver by poorly crystallized manganese oxides

    Science.gov (United States)

    Anderson, B.J.; Jenne, E.A.; Chao, T.T.

    1973-01-01

    The sorption of silver by poorly crystallized manganese oxides was studied using synthesized samples of three members of the manganous manganite (birnessite) group, of different chemical composition and crystallinity, and a poorly organized ??-MnO2. All four oxides sorbed significant quantities of silver. The manganous manganites showed the greatest sorption (up to 0.5 moles silver/mole MnOx at pH 7) while the ??-MnO2 showed the least (0.3 moles silver/ mole MnOx at pH 7). Sorption of silver was adequately described by the Langmuir equation over a considerable concentration range. The relationship failed at low pH values and high equilibrium silver concentrations. The sorption capacity showed a direct relationship with pH. However, the rate of increase of sorption capacity decreased at the higher pH values. Silver sorption maxima. were not directly related to surface area but appeared to vary with the amount of occluded sodium and potassium present in the manganese oxide. The important processes involved in the uptake of silver by the four poorly crystallized manganese oxides ara considered to be surface exchange for manganese, potassium and sodium as well as exchange for structural manganese, potassium and sodium. ?? 1973.

  5. Manganese oxide-based materials as electrochemical supercapacitor electrodes.

    Science.gov (United States)

    Wei, Weifeng; Cui, Xinwei; Chen, Weixing; Ivey, Douglas G

    2011-03-01

    Electrochemical supercapacitors (ECs), characteristic of high power and reasonably high energy densities, have become a versatile solution to various emerging energy applications. This critical review describes some materials science aspects on manganese oxide-based materials for these applications, primarily including the strategic design and fabrication of these electrode materials. Nanostructurization, chemical modification and incorporation with high surface area, conductive nanoarchitectures are the three major strategies in the development of high-performance manganese oxide-based electrodes for EC applications. Numerous works reviewed herein have shown enhanced electrochemical performance in the manganese oxide-based electrode materials. However, many fundamental questions remain unanswered, particularly with respect to characterization and understanding of electron transfer and atomic transport of the electrochemical interface processes within the manganese oxide-based electrodes. In order to fully exploit the potential of manganese oxide-based electrode materials, an unambiguous appreciation of these basic questions and optimization of synthesis parameters and material properties are critical for the further development of EC devices (233 references).

  6. Defined contribution health benefits.

    Science.gov (United States)

    Fronstin, P

    2001-03-01

    This Issue Brief discusses the emerging issue of "defined contribution" (DC) health benefits. The term "defined contribution" is used to describe a wide variety of approaches to the provision of health benefits, all of which have in common a shift in the responsibility for payment and selection of health care services from employers to employees. DC health benefits often are mentioned in the context of enabling employers to control their outlay for health benefits by avoiding increases in health care costs. DC health benefits may also shift responsibility for choosing a health plan and the associated risks of choosing a plan from employers to employees. There are three primary reasons why some employers currently are considering some sort of DC approach. First, they are once again looking for ways to keep their health care cost increases in line with overall inflation. Second, some employers are concerned that the public "backlash" against managed care will result in new legislation, regulations, and litigation that will further increase their health care costs if they do not distance themselves from health care decisions. Third, employers have modified not only most employee benefit plans, but labor market practices in general, by giving workers more choice, control, and flexibility. DC-type health benefits have existed as cafeteria plans since the 1980s. A cafeteria plan gives each employee the opportunity to determine the allocation of his or her total compensation (within employer-defined limits) among various employee benefits (primarily retirement or health). Most types of DC health benefits currently being discussed could be provided within the existing employment-based health insurance system, with or without the use of cafeteria plans. They could also allow employees to purchase health insurance directly from insurers, or they could drive new technologies and new forms of risk pooling through which health care services are provided and financed. DC health

  7. On Defining Mass

    Science.gov (United States)

    Hecht, Eugene

    2011-01-01

    Though central to any pedagogical development of physics, the concept of mass is still not well understood. Properly defining mass has proven to be far more daunting than contemporary textbooks would have us believe. And yet today the origin of mass is one of the most aggressively pursued areas of research in all of physics. Much of the excitement surrounding the Large Hadron Collider at CERN is associated with discovering the mechanism responsible for the masses of the elementary particles. This paper will first briefly examine the leading definitions, pointing out their shortcomings. Then, utilizing relativity theory, it will propose—for consideration by the community of physicists—a conceptual definition of mass predicated on the more fundamental concept of energy, more fundamental in that everything that has mass has energy, yet not everything that has energy has mass.

  8. Implementing Software Defined Radio

    CERN Document Server

    Grayver, Eugene

    2013-01-01

    Software Defined Radio makes wireless communications easier, more efficient, and more reliable. This book bridges the gap between academic research and practical implementation. When beginning a project, practicing engineers, technical managers, and graduate students can save countless hours by considering the concepts presented in these pages. The author covers the myriad options and trade-offs available when selecting an appropriate hardware architecture. As demonstrated here, the choice between hardware- and software-centric architecture can mean the difference between meeting an aggressive schedule and bogging down in endless design iterations. Because of the author’s experience overseeing dozens of failed and successful developments, he is able to present many real-life examples. Some of the key concepts covered are: Choosing the right architecture for the market – laboratory, military, or commercial Hardware platforms – FPGAs, GPPs, specialized and hybrid devices Standardization efforts to ens...

  9. Defining cyber warfare

    Directory of Open Access Journals (Sweden)

    Dragan D. Mladenović

    2012-04-01

    Full Text Available Cyber conflicts represent a new kind of warfare that is technologically developing very rapidly. Such development results in more frequent and more intensive cyber attacks undertaken by states against adversary targets, with a wide range of diverse operations, from information operations to physical destruction of targets. Nevertheless, cyber warfare is waged through the application of the same means, techniques and methods as those used in cyber criminal, terrorism and intelligence activities. Moreover, it has a very specific nature that enables states to covertly initiate attacks against their adversaries. The starting point in defining doctrines, procedures and standards in the area of cyber warfare is determining its true nature. In this paper, a contribution to this effort was made through the analysis of the existing state doctrines and international practice in the area of cyber warfare towards the determination of its nationally acceptable definition.

  10. Defining the mobilome.

    Science.gov (United States)

    Siefert, Janet L

    2009-01-01

    This chapter defines the agents that provide for the movement of genetic material which fuels the adaptive potential of life on our planet. The chapter has been structured to be broadly comprehensive, arbitrarily categorizing the mobilome into four classes: (1) transposons, (2) plasmids, (3) bacteriophage, and (4) self-splicing molecular parasites.Our increasing understanding of the mobilome is as dynamic as the mobilome itself. With continuing discovery, it is clear that nature has not confined these genomic agents of change to neat categories, but rather the classification categories overlap and intertwine. Massive sequencing efforts and their published analyses are continuing to refine our understanding of the extent of the mobilome. This chapter provides a framework to describe our current understanding of the mobilome and a foundation on which appreciation of its impact on genome evolution can be understood.

  11. Software Defined Networking

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius

    Network Service Providers (NSP) often choose to overprovision their networks instead of deploying proper Quality of Services (QoS) mechanisms that allow for traffic differentiation and predictable quality. This tendency of overprovisioning is not sustainable for the simple reason that network...... resources are limited. Hence, to counteract this trend, current QoS mechanisms must become simpler to deploy and operate, in order to motivate NSPs to employ QoS techniques instead of overprovisioning. Software Defined Networking (SDN) represents a paradigm shift in the way telecommunication and data...... generic perspective (e.g. service provisioning speed, resources availability). As a result, new mechanisms for providing QoS are proposed, solutions for SDN-specific QoS challenges are designed and tested, and new network management concepts are prototyped, all aiming to improve QoS for network services...

  12. Solvent extractions applications to hydrometallurgy. Pt.III: Nickel, cobalt, manganese and ocean nodules

    International Nuclear Information System (INIS)

    Amer, S.

    1981-01-01

    The main applications of solvent extraction to the hydrometallurgy of nickel, cobalt, manganese and manganese rich ocean nodules, which also contain nickel, cooper and cobalt, are exposed. A short description of the processes with commercial applications is made. (author)

  13. Effects of dietary manganese contents on 54Mn metabolism in mice

    International Nuclear Information System (INIS)

    Sato, I.; Matsusaka, N.; Kobayashi, H.; Nishimura, Y.

    1996-01-01

    Several parameters of 54 Mn metabolism were noted in mice maintained on diets with manganese contents of 80 to 8000 mg/kg. Excretion of 54 Mn was promoted as the dietary manganese contents increased. Clearance of 54 Mn from the liver, kidneys, pancreas, and spleen was markedly accelerated by feeding mice a high-manganese diet, but clearance from the muscles, femurs, and brain was relatively insensitive to the dietary manganese. Manganese concentrations in the tissue were regulated homoestatically upto the dietary manganese content of 2400 mg/kg, but marked accumulations of manganese occurred when mice were given 8000 mg/kg diet. No toxic symptoms were found up to the 2400 mg/kg diet, but consumption of the 8000 mg/kg diet was less than for other diets. These results suggest that an oral intake of excess manganese is effective for promoting the excretion of 54 Mn from a body contaminated with this isotope. (author)

  14. The complex compounds of manganese (II) with poly dental ligands and polyhedron borane anions

    International Nuclear Information System (INIS)

    Buranova, S.A.

    1996-01-01

    The purpose of the present work is synthesis of complex compounds of manganese with organic ligands. Their studying by spectroscopic methods purposely to determinate the influence of borane anions on composition and structure of coordinating sphere of manganese

  15. Biological Superoxide In Manganese Oxide Formation

    Science.gov (United States)

    Hansel, C.; Learman, D.; Zeiner, C.; Santelli, C. M.

    2011-12-01

    Manganese (Mn) oxides are among the strongest sorbents and oxidants within the environment, controlling the fate and transport of numerous elements and the degradation of recalcitrant carbon. Both bacteria and fungi mediate the oxidation of Mn(II) to Mn(III/IV) oxides but the genetic and biochemical mechanisms responsible remain poorly understood. Furthermore, the physiological basis for microbial Mn(II) oxidation remains an enigma. We have recently reported that a common marine bacterium (Roseobacter sp. AzwK-3b) oxidizes Mn(II) via reaction with extracellular superoxide (O2-) produced during exponential growth. Here we expand this superoxide-mediated Mn(II) oxidation pathway to fungi, introducing a surprising homology between prokaryotic and eukaryotic metal redox processes. For instance, Stibella aciculosa, a common soil Ascomycete filamentous fungus, precipitates Mn oxides at the base of asexual reproductive structures (synnemata) used to support conidia (Figure 1). This distribution is a consequence of localized production of superoxide (and it's dismutation product hydrogen peroxide, H2O2), leading to abiotic oxidation of Mn(II) by superoxide. Disruption of NADPH oxidase activity using the oxidoreductase inhibitor DPI leads to diminished cell differentiation and subsequent Mn(II) oxidation inhibition. Addition of Cu(II) (an effective superoxide scavenger) leads to a concentration dependent decrease in Mn oxide formation. We predict that due to the widespread production of extracellular superoxide within the fungal and likely bacterial kingdoms, biological superoxide may be an important contributor to the cycling of Mn, as well as other metals (e.g., Hg, Fe). Current and future explorations of the genes and proteins involved in superoxide production and Mn(II) oxidation will ideally lend insight into the physiological and biochemical basis for these processes.

  16. Manganese and the Evolution of Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2015-09-01

    Oxygenic photosynthesis is the most important bioenergetic event in the history of our planet—it evolved once within the Cyanobacteria, and remained largely unchanged as it was transferred to algae and plants via endosymbiosis. Manganese plays a fundamental role in this history because it lends the critical redox behavior of the water-oxidizing complex of photosystem II. Constraints from the photoassembly of the Mn-bearing water-oxidizing complex fuel the hypothesis that Mn(II) once played a key role as an electron donor for anoxygenic photosynthesis prior to the evolution of oxygenic photosynthesis. Here we review the growing body of geological and geochemical evidence from the Archean and Paleoproterozoic sedimentary records that supports this idea and demonstrates that the oxidative branch of the Mn cycle switched on prior to the rise of oxygen. This Mn-oxidizing phototrophy hypothesis also receives support from the biological record of extant phototrophs, and can be made more explicit by leveraging constraints from structural biology and biochemistry of photosystem II in Cyanobacteria. These observations highlight that water-splitting in photosystem II evolved independently from a homodimeric ancestral type II reaction center capable of high potential photosynthesis and Mn(II) oxidation, which is required by the presence of homologous redox-active tyrosines in the modern heterodimer. The ancestral homodimer reaction center also evolved a C-terminal extension that sterically precluded standard phototrophic electron donors like cytochrome c, cupredoxins, or high-potential iron-sulfur proteins, and could only complete direct oxidation of small molecules like Mn2+, and ultimately water.

  17. Efficacies of manganese chloride and Ca-DTPA for the elimination of incorporated manganese-54 in mice

    International Nuclear Information System (INIS)

    Sato, Itaru; Matsusaka, Naonori; Shinagawa, Kunihiro; Kobayashi, Haruo; Nishimura, Yoshikazu.

    1993-01-01

    Efficacies of manganese chloride and Ca-DTPA (calcium diethylenetriaminepentaacetic acid) for the elimination of incorporated 54 Mn were investigated in mice. Each mouse was given an intraperitoneal injection of 54 Mn and initial whole-body radioactivity was measured immediately. Manganese chloride (10 mg-Mn/kg) or Ca-DTPA (10 or 100 mg/kg) was injected intraperitoneally once or repeatedly at various times after 54 Mn injection. Efficacies for elimination were estimated by measuring the whole body retention of 54 Mn for 14 or 21 days. A single injection of manganese chloride eliminated more than 80% of the incorporated 54 Mn when it was injected within 24 h after the injection of 54 Mn. Although the efficacy was decreased with the passage of time after the injection of 54 Mn, about 50% was still eliminated after 14 days. Repeated injection of this agent raised the efficacy, but the second or later injection was less effective than the first injection. Ca-DTPA eliminated the incorporated 54 Mn by 57% for 100 mg/kg and by 19% for 10 mg/kg when it was injected after 3 h. But after 6 h or later, Ca-DTPA had little efficacy. These results indicate that manganese chloride is very effective to eliminate the 54 Mn from accidentally contaminated persons and the efficacy of Ca-DTPA is less than that of manganese chloride. (author)

  18. Contribution of arginase to manganese metabolism of Aspergillus niger.

    Science.gov (United States)

    Keni, Sarita; Punekar, Narayan S

    2016-02-01

    Aspects of manganese metabolism during normal and acidogenic growth of Aspergillus niger were explored. Arginase from this fungus was a Mn[II]-enzyme. The contribution of the arginase protein towards A. niger manganese metabolism was investigated using arginase knockout (D-42) and arginase over-expressing (ΔXCA-29) strains of A. niger NCIM 565. The Mn[II] contents of various mycelial fractions were found in the order: D-42 strain niger mycelia harvested from acidogenic growth media contain substantially less Mn[II] as compared to those from normal growth media. Nevertheless, acidogenic mycelia harbor considerable Mn[II] levels and a functional arginase. Altered levels of mycelial arginase protein did not significantly influence citric acid production. The relevance of arginase to cellular Mn[II] pool and homeostasis was evaluated and the results suggest that arginase regulation could occur via manganese availability.

  19. Manganese and Iron Catalysts in Alkyd Paints and Coatings

    Directory of Open Access Journals (Sweden)

    Ronald Hage

    2016-04-01

    Full Text Available Many paint, ink and coating formulations contain alkyd-based resins which cure via autoxidation mechanisms. Whilst cobalt-soaps have been used for many decades, there is a continuing and accelerating desire by paint companies to develop alternatives for the cobalt soaps, due to likely classification as carcinogens under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals legislation. Alternative driers, for example manganese and iron soaps, have been applied for this purpose. However, relatively poor curing capabilities make it necessary to increase the level of metal salts to such a level that often coloring of the paint formulation occurs. More recent developments include the application of manganese and iron complexes with a variety of organic ligands. This review will discuss the chemistry of alkyd resin curing, the applications and reactions of cobalt-soaps as curing agents, and, subsequently, the paint drying aspects and mechanisms of (model alkyd curing using manganese and iron catalysts.

  20. Factors affecting radium removal using mixed iron-manganese oxides

    International Nuclear Information System (INIS)

    Mott, H.V. Singh, S.; Kondapally, V.R.

    1993-01-01

    Batch experiments confirmed that sorption of radium by a mixed iron-manganese oxide solid phase shows promise for treating radium-contaminated water. The capacities of these mixed oxides for sorption of radium depend on the composition of the solid phase, the pH of the aqueous solution, and the presence of competing cations. The removal of the oxide-radium complexes from aqueous suspension by manganese greensand filtration was also investigated. It was found that influent radium concentrations of 100 pCi/L were reduced to 2--9 pCi/L by this process. Additional study of the fate of radium in manganese greensand filters is recommended before this procedure is used for drinking water treatment

  1. A redox-assisted supramolecular assembly of manganese oxide nanotube

    International Nuclear Information System (INIS)

    Tao Li; Sun Chenggao; Fan Meilian; Huang Caijuan; Wu Hailong; Chao Zisheng; Zhai Hesheng

    2006-01-01

    In this paper, we report the hydrothermal synthesis of manganese oxide nanotube from an aqueous medium of pH 7, using KMnO 4 and MnCl 2 as inorganic precursors, polyoxyethylene (10) nonyl phenyl ether (TX-10) a surfactant and acetaldehyde an additive. The characterization of X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and N 2 adsorption at 77 K (BET) reveals that the synthesized manganese oxide nanotube has a mesopore size of ca. 3.65 nm and a wall thickness of ca. 12 nm, with the wall being composed of microporous crystals of monoclinic manganite. The X-ray photoelectron spectroscopy (XPS) result demonstrates a decrease of the binding energy of the Mn 3+ in the manganese oxide nanotube, which may be related to both the nanotubular morphology and the crystalline pore wall. A mechanism of a redox-assisted supramolecular assembly, regulated by acetaldehyde, is postulated

  2. Factors affecting radium removal using mixed iron-manganese oxides

    Energy Technology Data Exchange (ETDEWEB)

    Mott, H.V. Singh, S.; Kondapally, V.R. (South Dakota School of Mines and Technology, Rapid City, SD (United States))

    1993-10-01

    Batch experiments confirmed that sorption of radium by a mixed iron-manganese oxide solid phase shows promise for treating radium-contaminated water. The capacities of these mixed oxides for sorption of radium depend on the composition of the solid phase, the pH of the aqueous solution, and the presence of competing cations. The removal of the oxide-radium complexes from aqueous suspension by manganese greensand filtration was also investigated. It was found that influent radium concentrations of 100 pCi/L were reduced to 2--9 pCi/L by this process. Additional study of the fate of radium in manganese greensand filters is recommended before this procedure is used for drinking water treatment.

  3. Defining the Anthropocene

    Science.gov (United States)

    Lewis, Simon; Maslin, Mark

    2016-04-01

    Time is divided by geologists according to marked shifts in Earth's state. Recent global environmental changes suggest that Earth may have entered a new human-dominated geological epoch, the Anthropocene. Should the Anthropocene - the idea that human activity is a force acting upon the Earth system in ways that mean that Earth will be altered for millions of years - be defined as a geological time-unit at the level of an Epoch? Here we appraise the data to assess such claims, first in terms of changes to the Earth system, with particular focus on very long-lived impacts, as Epochs typically last millions of years. Can Earth really be said to be in transition from one state to another? Secondly, we then consider the formal criteria used to define geological time-units and move forward through time examining whether currently available evidence passes typical geological time-unit evidence thresholds. We suggest two time periods likely fit the criteria (1) the aftermath of the interlinking of the Old and New Worlds, which moved species across continents and ocean basins worldwide, a geologically unprecedented and permanent change, which is also the globally synchronous coolest part of the Little Ice Age (in Earth system terms), and the beginning of global trade and a new socio-economic "world system" (in historical terms), marked as a golden spike by a temporary drop in atmospheric CO2, centred on 1610 CE; and (2) the aftermath of the Second World War, when many global environmental changes accelerated and novel long-lived materials were increasingly manufactured, known as the Great Acceleration (in Earth system terms) and the beginning of the Cold War (in historical terms), marked as a golden spike by the peak in radionuclide fallout in 1964. We finish by noting that the Anthropocene debate is politically loaded, thus transparency in the presentation of evidence is essential if a formal definition of the Anthropocene is to avoid becoming a debate about bias. The

  4. [Multiple meningiomas].

    Science.gov (United States)

    Terrier, L-M; François, P

    2016-06-01

    Multiple meningiomas (MMs) or meningiomatosis are defined by the presence of at least 2 lesions that appear simultaneously or not, at different intracranial locations, without the association of neurofibromatosis. They present 1-9 % of meningiomas with a female predominance. The occurrence of multiple meningiomas is not clear. There are 2 main hypotheses for their development, one that supports the independent evolution of these tumors and the other, completely opposite, that suggests the propagation of tumor cells of a unique clone transformation, through cerebrospinal fluid. NF2 gene mutation is an important intrinsic risk factor in the etiology of multiple meningiomas and some exogenous risk factors have been suspected but only ionizing radiation exposure has been proven. These tumors can grow anywhere in the skull but they are more frequently observed in supratentorial locations. Their histologic types are similar to unique meningiomas of psammomatous, fibroblastic, meningothelial or transitional type and in most cases are benign tumors. The prognosis of these tumors is eventually good and does not differ from the unique tumors except for the cases of radiation-induced multiple meningiomas, in the context of NF2 or when diagnosed in children where the outcome is less favorable. Each meningioma lesion should be dealt with individually and their multiple character should not justify their resection at all costs. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Preparation of the electrochemically formed spinel-lithium manganese oxides

    Energy Technology Data Exchange (ETDEWEB)

    Katakura, Katsumi; Wada, Kohei; Kajiki, Yoshiyuki; Yamamoto, Akiko [Department of Chemical Engineering, Nara National College of Technology, 22 Yata-cho Yamotokoriyama, Nara 639-1080 (Japan); Ogumi, Zempachi [Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan)

    2009-04-01

    Electrochemically formed spinel-lithium manganese oxides were synthesized from manganese hydroxides prepared by a cathodic electrochemical precipitation from various concentrations of manganese nitrate solutions. Two types of manganese hydroxides were formed from diluted and concentrated Mn(NO{sub 3}){sub 2} aqueous solutions. Uniform and equi-sized disk shaped Mn(OH){sub 2} crystals of 0.2-5 {mu}m in diameter were obtained on a Pt substrate after the electrochemical precipitation from lower concentration of ranging from 2 mmol dm{sup -3} to 2 mol dm{sup -3} Mn(NO{sub 3}){sub 2} aq., while the grass blade-like precipitate which is ascribed to manganese hydroxide with 20-80 {mu}m long and 1-5 {mu}m wide were formed from concentrated Mn(NO{sub 3}){sub 2} aq. Both manganese hydroxides gave the electrochemically formed spinel-LiMn{sub 2}O{sub 4} onto a Pt sheet, which is ready for electrochemical measurement, after calcination of the Li incorporated precipitate at 750 C without any additives. While the shape and size of the secondary particle frameworks (aggregates) of the electrochemically formed spinel-LiMn{sub 2}O{sub 4} can be controlled by the electrolysis conditions, the nanostructured primary crystals of 200 nm in diameter were obtained in all cases except that the fiber-like nanostructured spinel-LiMn{sub 2}O{sub 4} crystals with 200 nm in diameter were obtained from concentrated Mn(NO{sub 3}){sub 2} aq. Though these two types of electrochemically formed spinel-LiMn{sub 2}O{sub 4} showed well-shaped CVs even in higher scan rates, it would be suitable for high power density battery applications. These behaviors are assumed to be ascribed to the crystal size and shape of the processed spinel-LiMn{sub 2}O{sub 4}. (author)

  6. Manganese oxidation state mediates toxicity in PC12 cells

    International Nuclear Information System (INIS)

    Reaney, S.H.; Smith, D.R.

    2005-01-01

    The role of the manganese (Mn) oxidation state on cellular Mn uptake and toxicity is not well understood. Therefore, undifferentiated PC12 cells were exposed to 0-200 μM Mn(II)-chloride or Mn(III)-pyrophosphate for 24 h, after which cellular manganese levels were measured along with measures of cell viability, function, and cytotoxicity (trypan blue exclusion, medium lactate dehydrogenase (LDH), 8-isoprostanes, cellular ATP, dopamine, serotonin, H-ferritin, transferrin receptor (TfR), Mn-superoxide dismutase (MnSOD), and copper-zinc superoxide dismutase (CuZnSOD) protein levels). Exposures to Mn(III) >10 μM produced 2- to 5-fold higher cellular manganese levels than equimolar exposures to Mn(II). Cell viability and ATP levels both decreased at the highest Mn(II) and Mn(III) exposures (150-200 μM), while Mn(III) exposures produced increases in LDH activity at lower exposures (≥50 μM) than did Mn(II) (200 μM only). Mn(II) reduced cellular dopamine levels more than Mn(III), especially at the highest exposures (50% reduced at 200 μM Mn(II)). In contrast, Mn(III) produced a >70% reduction in cellular serotonin at all exposures compared to Mn(II). Different cellular responses to Mn(II) exposures compared to Mn(III) were also observed for H-ferritin, TfR, and MnSOD protein levels. Notably, these differential effects of Mn(II) versus Mn(III) exposures on cellular toxicity could not simply be accounted for by the different cellular levels of manganese. These results suggest that the oxidation state of manganese exposures plays an important role in mediating manganese cytotoxicity

  7. Statistical Optimization of Synthesis of Manganese Carbonates Nanoparticles by Precipitation Methods

    International Nuclear Information System (INIS)

    Javidan, A.; Rahimi-Nasrabadi, M.; Davoudi, A.A.

    2011-01-01

    In this study, an orthogonal array design (OAD), OA9, was employed as a statistical experimental method for the controllable, simple and fast synthesis of manganese carbonate nanoparticle. Ultrafine manganese carbonate nanoparticles were synthesized by a precipitation method involving the addition of manganese ion solution to the carbonate reagent. The effects of reaction conditions, for example, manganese and carbonate concentrations, flow rate of reagent addition and temperature, on the diameter of the synthesized manganese carbonate nanoparticle were investigated. The effects of these factors on the width of the manganese carbonate nanoparticle were quantitatively evaluated by the analysis of variance (ANOVA). The results showed that manganese carbonate nanoparticle can be synthesized by controlling the manganese concentration, flow rate and temperature. Finally, the optimum conditions for the synthesis of manganese carbonate nanoparticle by this simple and fast method were proposed. The results of ANOVA showed that 0.001 mol/ L manganese ion and carbonate reagents concentrations, 2.5 mL/ min flow rate for the addition of the manganese reagent to the carbonate solution and 0 degree Celsius temperature are the optimum conditions for producing manganese carbonate nanoparticle with 75 ± 25 nm width. (author)

  8. 40 CFR 721.10010 - Barium manganese oxide (BaMnO3).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium manganese oxide (BaMnO3). 721... Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium manganese oxide (BaMnO3) (PMN P-00...

  9. Teleology and Defining Sex.

    Science.gov (United States)

    Gamble, Nathan K; Pruski, Michal

    2018-07-01

    Disorders of sexual differentiation lead to what is often referred to as an intersex state. This state has medical, as well as some legal, recognition. Nevertheless, the question remains whether intersex persons occupy a state in between maleness and femaleness or whether they are truly men or women. To answer this question, another important conundrum needs to be first solved: what defines sex? The answer seems rather simple to most people, yet when morphology does not coincide with haplotypes, and genetics might not correlate with physiology the issue becomes more complex. This paper tackles both issues by establishing where the essence of sex is located and by superimposing that framework onto the issue of the intersex. This is achieved through giving due consideration to the biology of sexual development, as well as through the use of a teleological framework of the meaning of sex. Using a range of examples, the paper establishes that sex cannot be pinpointed to one biological variable but is rather determined by how the totality of one's biology is oriented towards biological reproduction. A brief consideration is also given to the way this situation could be comprehended from a Christian understanding of sex and suffering.

  10. Manganese and lead in dust fall accumulation in elementary schools near a ferromanganese alloy plant

    Energy Technology Data Exchange (ETDEWEB)

    Menezes-Filho, José Antonio, E-mail: antomen@ufba.br [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Souza, Karine O. Fraga de, E-mail: karinefraga11@hotmail.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Rodrigues, Juliana L. Gomes, E-mail: juuhrodrigues@icloud.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Santos, Nathália Ribeiro dos, E-mail: nathalia-rib@hotmail.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Bandeira, Matheus de Jesus, E-mail: matheusbandeira1@hotmail.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Koin, Ng Lai, E-mail: nglaikoin@hotmail.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Oliveira, Sérgio S. do Prado, E-mail: sergiosprado.33@gmail.com [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); Godoy, Ana Leonor P. Campos, E-mail: leonor.godoy@ufba.br [Federal University of Bahia, College of Pharmacy, Laboratory of Toxicology, Avenue Barão Jeremoabo, s/n, Ondina, 40170-115 Salvador, Bahia (Brazil); and others

    2016-07-15

    Previous studies have shown elevated airborne manganese (Mn) in villages adjacent to a Mn alloy production plant in Brazil and negative associations between biomarkers of Mn and children's cognition and behavior. Since small Mn particles may be carried for long distances, we measured manganese (Mn) and lead (Pb) dust fall accumulation in 15 elementary schools, located between 1.25 and 6.48 km from the plant in the municipality of Simões Filho, Bahia, Brazil. Passive samplers (polyethylene Petri dishes) were set in interior and exterior environments. After 30 days, the samplers’ content was solubilized with diluted nitric acid and Mn and Pb levels were analyzed by electrothermal absorption spectrometry. The overall geometric mean and range of Mn and Pb accumulation in dust fall (loading rates) were 1582 μg Mn/m{sup 2}/30 days (37–37,967) and 43.2 μg Pb/m{sup 2}/30 days (2.9–210.4). A logarithmic decrease in interior and exterior Mn loading rates was observed with distance from the ferro-manganese alloy plant. Multiple regression analyses of log-transformed Mn loading rate within the schools showed a positive association with Mn levels in outdoor dust, a negative association with distance from the plant; as well, wind direction (downwind>upwind) and school location (urban>rural) entered significantly into the model. For the interior school environments, located within a 2-km radius from the plant, loading rate was, on average, 190 times higher than the Mn levels reported by Gulson et al., (2014) in daycare centers in Sydney, Australia, using a similar method. Pb loading rates were not associated with distance from the plant and were lower than the rates observed in the same daycare centers in Sydney. Our findings suggest that a significant portion of the children in this town in Brazil may be exposed to airborne Mn at concentrations that may affect their neurodevelopment. - Highlights: • Manganese levels in settled dust in schools are inversely

  11. Manganese and lead in dust fall accumulation in elementary schools near a ferromanganese alloy plant

    International Nuclear Information System (INIS)

    Menezes-Filho, José Antonio; Souza, Karine O. Fraga de; Rodrigues, Juliana L. Gomes; Santos, Nathália Ribeiro dos; Bandeira, Matheus de Jesus; Koin, Ng Lai; Oliveira, Sérgio S. do Prado; Godoy, Ana Leonor P. Campos

    2016-01-01

    Previous studies have shown elevated airborne manganese (Mn) in villages adjacent to a Mn alloy production plant in Brazil and negative associations between biomarkers of Mn and children's cognition and behavior. Since small Mn particles may be carried for long distances, we measured manganese (Mn) and lead (Pb) dust fall accumulation in 15 elementary schools, located between 1.25 and 6.48 km from the plant in the municipality of Simões Filho, Bahia, Brazil. Passive samplers (polyethylene Petri dishes) were set in interior and exterior environments. After 30 days, the samplers’ content was solubilized with diluted nitric acid and Mn and Pb levels were analyzed by electrothermal absorption spectrometry. The overall geometric mean and range of Mn and Pb accumulation in dust fall (loading rates) were 1582 μg Mn/m 2 /30 days (37–37,967) and 43.2 μg Pb/m 2 /30 days (2.9–210.4). A logarithmic decrease in interior and exterior Mn loading rates was observed with distance from the ferro-manganese alloy plant. Multiple regression analyses of log-transformed Mn loading rate within the schools showed a positive association with Mn levels in outdoor dust, a negative association with distance from the plant; as well, wind direction (downwind>upwind) and school location (urban>rural) entered significantly into the model. For the interior school environments, located within a 2-km radius from the plant, loading rate was, on average, 190 times higher than the Mn levels reported by Gulson et al., (2014) in daycare centers in Sydney, Australia, using a similar method. Pb loading rates were not associated with distance from the plant and were lower than the rates observed in the same daycare centers in Sydney. Our findings suggest that a significant portion of the children in this town in Brazil may be exposed to airborne Mn at concentrations that may affect their neurodevelopment. - Highlights: • Manganese levels in settled dust in schools are inversely associated

  12. Manganese Loading and Photosystem II Stability are Key Components of Manganese Efficiency in Plants

    DEFF Research Database (Denmark)

    Schmidt, Sidsel Birkelund

    Manganese (Mn) deficiency constitutes a major plant nutritional problem in commercial crop production of winter cereals. In plants, Mn has an indispensable role in the oxygen evolving complex (OEC) of photosystem II (PSII). Hence, the consequences of Mn deficiency are reduced plant growth......, and eventually substantial yield losses. It is well known, that genotypes within plant species differ considerably in tolerance to growth under Mn limiting conditions, a phenomenon designated as Mn efficiency. However, the physiological responses reflecting the underlying mechanisms of Mn efficiency are still...... not fully understood. In this PhD study, a new method for determination and characterization of metal binding in size-fractionated photosynthetic protein complexes from barley thylakoids was established. The applicability of the method was shown by quantification of Mn binding in PSII from thylakoids of two...

  13. Determination of the oxidizing capacity of manganese ores.

    Science.gov (United States)

    Prasad, R

    1974-09-01

    An accurate method is described for determining the amount of active oxygen in manganese ores, based on the oxidation-reduction reaction between the ore and arsenic(III) in presence of ammonium molybdate, followed by the back-titration of excess of arsenic(III) with cerium(IV), using osmium tetroxide as catalyst and Disulphine Blue V as indicator. A survey has been made of the applicability of this method to various pyrolusite ores containing less than 0.2% phosphorus. Aluminium(III), copper(II), iron(III), manganese(II), and molybdenum(VI) do not interfere. Up to 30% phosphorus(V) causes no interference.

  14. Biostimulation strategies to enhance manganese removal in drinking water biofilters

    DEFF Research Database (Denmark)

    Breda, Inês Lousinha Ribeiro; Ramsay, Loren; Søborg, Ditte

    to national drinking water criteria. The period during which virgin filter media matures into a fully functional biofilter is designated as the start-up period. The duration of a start-up for efficient manganese removal varies from weeks to more than a year. The aim of this study was to investigate...... growth and activity of specific bacteria. Biostimulation of virgin media to enhance initial manganese removal using different amendments strategies is possible especially in the early stages of filter development whereas autocatalytic processes appear to become dominant with time. The complex...

  15. Manganese removal from mine waters - investigating the occurrence and importance of manganese carbonates

    International Nuclear Information System (INIS)

    Bamforth, Selina M.; Manning, David A.C.; Singleton, Ian; Younger, Paul L.; Johnson, Karen L.

    2006-01-01

    Manganese is a common contaminant of mine water and other waste waters. Due to its high solubility over a wide pH range, it is notoriously difficult to remove from contaminated waters. Previous systems that effectively remove Mn from mine waters have involved oxidising the soluble Mn(II) species at an elevated pH using substrates such as limestone and dolomites. However it is currently unclear what effect the substrate type has upon abiotic Mn removal compared to biotic removal by in situ micro-organisms (biofilms). In order to investigate the relationship between substrate type, Mn precipitation and the biofilm community, net-alkaline Mn-contaminated mine water was treated in reactors containing one of the pure materials: dolomite, limestone, magnesite and quartzite. Mine water chemistry and Mn removal rates were monitored over a 3-month period in continuous-flow reactors. For all substrates except quartzite, Mn was removed from the mine water during this period, and Mn minerals precipitated in all cases. In addition, the plastic from which the reactor was made played a role in Mn removal. Manganese oxyhydroxides were formed in all the reactors; however, Mn carbonates (specifically kutnahorite) were only identified in the reactors containing quartzite and on the reactor plastic. Magnesium-rich calcites were identified in the dolomite and magnesite reactors, suggesting that the Mg from the substrate minerals may have inhibited Mn carbonate formation. Biofilm community development and composition on all the substrates was also monitored over the 3-month period using denaturing gradient gel electrophoresis (DGGE). The DGGE profiles in all reactors showed no change with time and no difference between substrate types, suggesting that any microbiological effects are independent of mineral substrate. The identification of Mn carbonates in these systems has important implications for the design of Mn treatment systems in that the provision of a carbonate-rich substrate

  16. Environmental contamination and human exposure to manganese--contribution of methylcyclopentadienyl manganese tricarbonyl in unleaded gasoline.

    Science.gov (United States)

    Zayed, J; Vyskocil, A; Kennedy, G

    1999-01-01

    The organomanganese compound MMT (methylcyclopentadienyl manganese tricarbonyl), an antiknock additive in unleaded gasoline, has been used in Canada since 1976. Indeed, Canada is the only country where MMT is almost exclusively used. In October 1995, by court decision the Environmental protection Agency (EPA) granted Ethyl's waiver for the use of MMT in the United States. Paradoxically, in 1997 the federal government of Canada adopted a law (C-29) that banned both the interprovincial trade and the importation for commercial purposes of manganese-based substances, including MMT. However, MMT is currently widely used in Canada because of substantial stockpiling, and six Canadian provinces are challenging the law in the courts. Moreover, MMT has been approved for use in Argentina, Australia, Bulgaria, Russia, and conditionally, in New Zealand. It has been suggested by some scientists that combustion of MMT may be a significant source of exposure to inorganic Mn in urban areas. The crucial question is whether Mn contamination from industrial sources combined with the additional contamination that would result from the widespread use of MMT would lead to toxic effects. Our research efforts have attempted to assess the environmental/ecosystem Mn contamination arising from the combustion of MMT in abiotic and biotic systems as well as human exposure. The experimental evidence acquired so far provides useful information on certain environmental consequences of the use of MMT as well as raising a number of questions. Our results gave evidence indicating that roadside air, soils, plants, and animals may be contaminated by Mn. As well, some specific groups of the population could have a higher level of exposure to Mn. Nevertheless, the levels of exposure remain below international guide values. Further studies and further characterization of dose-response relationships are thus needed to provide successful implementation of evidence-based risk-assessment approaches.

  17. Defining an emerging disease.

    Science.gov (United States)

    Moutou, F; Pastoret, P-P

    2015-04-01

    Defining an emerging disease is not straightforward, as there are several different types of disease emergence. For example, there can be a 'real' emergence of a brand new disease, such as the emergence of bovine spongiform encephalopathy in the 1980s, or a geographic emergence in an area not previously affected, such as the emergence of bluetongue in northern Europe in 2006. In addition, disease can emerge in species formerly not considered affected, e.g. the emergence of bovine tuberculosis in wildlife species since 2000 in France. There can also be an unexpected increase of disease incidence in a known area and a known species, or there may simply be an increase in our knowledge or awareness of a particular disease. What all these emerging diseases have in common is that human activity frequently has a role to play in their emergence. For example, bovine spongiform encephalopathy very probably emerged as a result of changes in the manufacturing of meat-and-bone meal, bluetongue was able to spread to cooler climes as a result of uncontrolled trade in animals, and a relaxation of screening and surveillance for bovine tuberculosis enabled the disease to re-emerge in areas that had been able to drastically reduce the number of cases. Globalisation and population growth will continue to affect the epidemiology of diseases in years to come and ecosystems will continue to evolve. Furthermore, new technologies such as metagenomics and high-throughput sequencing are identifying new microorganisms all the time. Change is the one constant, and diseases will continue to emerge, and we must consider the causes and different types of emergence as we deal with these diseases in the future.

  18. The INEL beryllium multiplication experiment

    International Nuclear Information System (INIS)

    Smith, J.R.; King, J.J.

    1991-03-01

    The experiment to measure the multiplication of 14-MeV neutrons in bulk beryllium has been completed. The experiment consists of determining the ratio of 56 Mn activities induced in a large manganese bath by a central 14-MeV neutron source, with and without a beryllium sample surrounding the source. In the manganese bath method a neutron source is placed at the center of a totally-absorbing aqueous solution of MnSo 4 . The capture of neutrons by Mn produces a 56 Mn activity proportional to the emission rate of the source. As applied to the measurement of the multiplication of 14- MeV neutrons in bulk beryllium, the neutron source is a tritium target placed at the end of the drift tube of a small deuteron accelerator. Surrounding the source is a sample chamber. When the sample chamber is empty, the neutrons go directly to the surrounding MnSO 4 solution, and produce a 56 Mn activity proportional to the neutron emission rate. When the chamber contains a beryllium sample, the neutrons first enter the beryllium and multiply through the (n,2n) process. Neutrons escaping from the beryllium enter the bath and produce a 56 Mn activity proportional to the neutron emission rate multiplied by the effective value of the multiplication in bulk beryllium. The ratio of the activities with and without the sample present is proportional to the multiplication value. Detailed calculations of the multiplication and all the systematic effects were made with the Monte Carlo program MCNP, utilizing both the Young and Stewart and the ENDF/B-VI evaluations for beryllium. Both data sets produce multiplication values that are in excellent agreement with the measurements for both raw and corrected values of the multiplication. We conclude that there is not real discrepancy between experimental and calculated values for the multiplication of neutrons in bulk beryllium. 12 figs., 11 tabs., 18 refs

  19. Pathophysiology of Manganese-Associated Neurotoxicity

    Science.gov (United States)

    Racette, Brad A.; Aschner, Michael; Guilarte, Tomas R.; Dydak, Ulrike; Criswell, Susan R.; Zheng, Wei

    2012-01-01

    Conference Summary Manganese (Mn) is a well established neurotoxin associated with specific damage to the basal ganglia in humans. The phenotype associated with Mn neurotoxicity was first described in two workers with occupational exposure to Mn oxide.(Couper, 1837) Although the description did not use modern clinical terminology, a parkinsonian illness characterized by slowness of movement (bradykinesia), masked facies, and gait impairment (postural instability) appears to have predominated. Nearly 100 years later an outbreak of an atypical parkinsonian illness in a Chilean Mn mine provided a phenotypic description of a fulminant neurologic disorder with parkinsonism, dystonia, and neuropsychiatric symptoms.(Rodier J, 1955) Exposures associated with this syndrome were massive and an order of magnitude greater than modern exposures.(Rodier J, 1955; Hobson et al., 2011) The clinical syndrome associated with Mn neurotoxicity has been called manganism. Modern exposures to Mn occur primarily through occupations in the steel industry and welding. These exposures are often chronic and varied, occurring over decades in the healthy workforce. Although the severe neurologic disorder described by Rodier and Couper are no longer seen, several reports have suggested a possible increased risk of neurotoxicity in these workers.(Racette et al., 2005b; Bowler et al., 2007; Harris et al., 2011) Based upon limited prior imaging and pathologic investigations into the pathophysiology of neurotoxicity in Mn exposed workers,(Huang et al., 2003) many investigators have concluded that the syndrome spares the dopamine system distinguishing manganism from Parkinson disease (PD), the most common cause of parkinsonism in the general population, and a disease with characteristic degenerative changes in the dopaminergic system.(Jankovic, 2005) The purpose of this symposium was to highlight recent advances in the understanding of the pathophysiology of Mn associated neurotoxicity from C. elegans

  20. Definably compact groups definable in real closed fields.II

    OpenAIRE

    Barriga, Eliana

    2017-01-01

    We continue the analysis of definably compact groups definable in a real closed field $\\mathcal{R}$. In [3], we proved that for every definably compact definably connected semialgebraic group $G$ over $\\mathcal{R}$ there are a connected $R$-algebraic group $H$, a definable injective map $\\phi$ from a generic definable neighborhood of the identity of $G$ into the group $H\\left(R\\right)$ of $R$-points of $H$ such that $\\phi$ acts as a group homomorphism inside its domain. The above result and o...

  1. The benefits of defining "snacks".

    Science.gov (United States)

    Hess, Julie M; Slavin, Joanne L

    2018-04-18

    Whether eating a "snack" is considered a beneficial or detrimental behavior is largely based on how "snack" is defined. The term "snack food" tends to connote energy-dense, nutrient-poor foods high in nutrients to limit (sugar, sodium, and/or saturated fat) like cakes, cookies, chips and other salty snacks, and sugar-sweetened beverages. Eating a "snack food" is often conflated with eating a "snack," however, leading to an overall perception of snacks as a dietary negative. Yet the term "snack" can also refer simply to an eating occasion outside of breakfast, lunch, or dinner. With this definition, the evidence to support health benefits or detriments to eating a "snack" remains unclear, in part because relatively few well-designed studies that specifically focus on the impact of eating frequency on health have been conducted. Despite these inconsistencies and research gaps, in much of the nutrition literature, "snacking" is still referred to as detrimental to health. As discussed in this review, however, there are multiple factors that influence the health impacts of snacking, including the definition of "snack" itself, the motivation to snack, body mass index of snack eaters, and the food selected as a snack. Without a definition of "snack" and a body of research using methodologically rigorous protocols, determining the health impact of eating a "snack" will continue to elude the nutrition research community and prevent the development of evidence-based policies about snacking that support public health. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Environmental Exposure to Manganese in Air: Associations with Cognitive Functions

    Science.gov (United States)

    Manganese (Mn), an essential element, can be neurotoxic in high doses. This cross-sectional study explored the oognitive function of adults residing in two towns (Marietta and East Liverpool, Ohio, USA) identified as having high levels of environmental airborne Mn from indu...

  3. Effect of increased manganese addition and mould type on the ...

    Indian Academy of Sciences (India)

    Administrator

    Effect of increased manganese addition and mould type on the slurry erosion characteristics of .... slurry erosion data in the form of bar diagrams for 5M24 and 10M24 ... being bigger in size with higher austenite retention and the attendant ...

  4. Adsorptive removal of manganese, arsenic and iron from groundwater

    NARCIS (Netherlands)

    Buamah, R.

    2009-01-01

    To determine the scale of the problem of arsenic, iron and manganese contamination of groundwater in Ghana a survey was performed in the first phase of the research to provide in depth information with respect to these contaminants. Presence of these mentioned contaminants in groundwater is not

  5. Effect of increased manganese addition and mould type on the ...

    Indian Academy of Sciences (India)

    The wear resistance of high chromium iron is well recorded. However, the same is not the case as regards the use of manganese at higher percentages in high chromium irons and its influence on wear behaviour. Hence, this work highlights the slurry wear characteristics of chromium (□ ◻ 16–19%) iron following the ...

  6. Arsenic, chromium, copper, iron, manganese, lead, selenium and ...

    African Journals Online (AJOL)

    2014-05-20

    May 20, 2014 ... Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the ... and sediment were collected and trace element concentrations were measured with an ICP-MS. ..... Clay minerals are known to have high sorption affinities ..... sediment/water quality interaction with particular reference to the.

  7. Manganese, iron and copper contents in leaves of maize plants ...

    African Journals Online (AJOL)

    Micronutrients such as boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) play important physiological roles in humans and animals. Zn and B are the micronutrients most often deficient in maize, in Iran. A completely randomized factorial block design experiment was carried out at Fars province of Iran during ...

  8. Assessment of Serum Levels of Magnesium and Manganese among ...

    African Journals Online (AJOL)

    Pregnant women in developing countries have been reported to consume diets with low density of minerals and essential trace elements. Therefore, this study aims to assess the serum levels of magnesium and manganese and its trimester correlates among pregnant women in Ika community of Delta state, Nigeria.

  9. Bioleaching of copper, aluminum, magnesium and manganese from ...

    African Journals Online (AJOL)

    The present study was done to check the bioleaching feasibility of brown shale for the recovery of copper (Cu), aluminum (Al), magnesium (Mg) and manganese (Mn) ions using Ganoderma lucidum. Different experimental parameters were optimized for the enhanced recovery of metals ions. Effect of different substrates like ...

  10. Bentonite Modification with Manganese Oxides and Its Characterization

    Czech Academy of Sciences Publication Activity Database

    Dolinská, S.; Schütz, T.; Znamenáčková, I.; Lovás, M.; Vaculíková, Lenka

    2015-01-01

    Roč. 35, č. 1 (2015), s. 213-218 ISSN 1640-4920 Institutional support: RVO:68145535 Keywords : bentonite * natrification * manganese oxide Subject RIV: CB - Analytical Chemistry, Separation http://www.potopk.com.pl/ Full _text/2015_full/IM%202-2015-a35.pdf

  11. Selective Synthesis of Manganese/Silicon Complexes in Supercritical Water

    Directory of Open Access Journals (Sweden)

    Jiancheng Wang

    2014-01-01

    Full Text Available A series of manganese salts (Mn(NO32, MnCl2, MnSO4, and Mn(Ac2 and silicon materials (silica sand, silica sol, and tetraethyl orthosilicate were used to synthesize Mn/Si complexes in supercritical water using a tube reactor. X-ray diffraction (XRD, X-ray photoelectron spectrometer (XPS, transmission electron microscopy (TEM, and scanning electron microscopy (SEM were employed to characterize the structure and morphology of the solid products. It was found that MnO2, Mn2O3, and Mn2SiO4 could be obtained in supercritical water at 673 K in 5 minutes. The roles of both anions of manganese salts and silicon species in the formation of manganese silicon complexes were discussed. The inorganic manganese salt with the oxyacid radical could be easily decomposed to produce MnO2/SiO2 and Mn2O3/SiO2. It is interesting to found that Mn(Ac2 can react with various types of silicon to produce Mn2SiO4. The hydroxyl groups of the SiO2 surface from different silicon sources enhance the reactivity of SiO2.

  12. Uranium in Pacific Deep-Sea Sediments and Manganese Nodules

    DEFF Research Database (Denmark)

    Kunzendorf, Helmar; Pluger, W. L.; Friedrich, G. H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water int...

  13. Covalent Functionalization of Carbon Nanotube by Tetrasubtituted Amino Manganese Phthalocyanine

    Institute of Scientific and Technical Information of China (English)

    Zheng Long YANG; Hong Zheng CHEN; Lei CAO; Han Yin LI; Mang WANG

    2004-01-01

    The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material (CGM), was also studied.

  14. Cognitive Function Related to Environmental Exposure to Manganese

    Science.gov (United States)

    Background: The towns of Marietta and East Liverpool (EL), Ohio, have been identified as having elevated manganese (Mn) in air due to industrial pollution. Objectives: To evaluate relationships between environmental Mn (Mn-air) exposure and distance from the source and cognitive...

  15. Experimental and numerical simulation of carbon manganese steel ...

    African Journals Online (AJOL)

    Experimental and numerical simulation of carbon manganese steel for cyclic plastic behaviour. J Shit, S Dhar, S Acharyya. Abstract. The paper deals with finite element modeling of saturated low cycle fatigue and the cyclic hardening phenomena of the materials Sa333 grade 6 carbon steel and SS316 stainless steel.

  16. Pilot study points way to iron/manganese removal

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, N.; Barnes, A. [Progressive Consulting Engineers Inc., Minneapolis, MN (United States)

    1994-12-31

    The use of coal, greensand and sand in filters for removing iron and manganese from the Brooklyn Park, Minnesota, water supply was investigated. The most effective and economic treatment involved using a dual media filtration and potassium permanganate as the oxidant.

  17. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Manganese heterocyclic tetraamine complex (generic). 721.10003 Section 721.10003 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... section. (2) The significant new uses are: (i) Industrial, commercial, and consumer activities...

  18. Manganese Catalyzed Regioselective C–H Alkylation: Experiment and Computation

    KAUST Repository

    Wang, Chengming

    2018-05-08

    A new efficient manganese-catalyzed selective C2-alkylation of indoles via carbenoid insertion has been achieved. The newly developed C-H functionalization protocol provides access to diverse products and shows good functional group tolerance. Mechanistic and computational studies support the formation of a Mn(CO)3 acetate complex as the catalytically active species.

  19. Manganese Catalyzed α-Olefination of Nitriles by Primary Alcohols.

    Science.gov (United States)

    Chakraborty, Subrata; Das, Uttam Kumar; Ben-David, Yehoshoa; Milstein, David

    2017-08-30

    Catalytic α-olefination of nitriles using primary alcohols, via dehydrogenative coupling of alcohols with nitriles, is presented. The reaction is catalyzed by a pincer complex of an earth-abundant metal (manganese), in the absence of any additives, base, or hydrogen acceptor, liberating dihydrogen and water as the only byproducts.

  20. Cognitive dysfunction, MRI findings and manganese levels in alcoholics

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Tsutomu; Nakane, Yoshibumi [Nagasaki Univ. (Japan). School of Medicine; Takahashi, Katsurou; Shimanaga, Masaki [National Nagasaki Medical Center, Omura (Japan)

    2002-12-01

    Alcoholic patients have been known to have brain atrophy and cognitive dysfunction. However, recent studies have reported bilateral signal hyperintensities of the globus pallidus on T1-weighted magnetic resonance imaging (MRI) in liver failure, findings that are typically associated with manganese intoxication. The present study compared brain atrophy on T1-weighted MRI, signal intensity ratios of the globus pallidus on T1-weighted MRI, whole blood manganese levels, and Wechsler Adult Intelligence Scale-Revised (WAIS-R) IQ parameters between alcoholics with and without liver cirrhosis, to investigate cognitive dysfunction, MRI findings and manganese levels in alcoholics. Pallidal hyperintensity was visually identified in 80% of alcoholic patients with liver cirrhosis. In addition, a significant correlation was seen between pallidal signal intensity (P.S.I.) ratio and blood manganese level. However, no significant correlations were found between pallidal signal intensity ratio and any of the WAIS-R parameters. These findings suggest that no direct connection exists between cognitive dysfunction and pallidal hyperintensity in alcoholic patients with liver cirrhosis. We confirmed that brain MRI in alcoholics could detect pallidal signal hyperintensity, suggesting severe liver dysfunction. In addition to diagnosis, brain MRI is useful for therapeutic psychoeducation to alcoholic patients with liver cirrhosis, visualizing the severe liver dysfunction. (author)

  1. Manganese Biogeochemistry in a Central Czech Republic Catchment

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Shanley, J. B.; Krám, P.; Mihaljevič, M.; Drahota, Petr

    2007-01-01

    Roč. 186, 1-4 (2007), s. 149-165 ISSN 0049-6979 R&D Projects: GA ČR GA205/04/0060 Institutional research plan: CEZ:AV0Z30130516 Keywords : manganese * catchment * weathering * biogeochemistry * biotite weathering * forest ecosystem * mass balance Subject RIV: DD - Geochemistry Impact factor: 1.224, year: 2007

  2. Cognitive dysfunction, MRI findings and manganese levels in alcoholics

    International Nuclear Information System (INIS)

    Itoh, Tsutomu; Nakane, Yoshibumi

    2002-01-01

    Alcoholic patients have been known to have brain atrophy and cognitive dysfunction. However, recent studies have reported bilateral signal hyperintensities of the globus pallidus on T1-weighted magnetic resonance imaging (MRI) in liver failure, findings that are typically associated with manganese intoxication. The present study compared brain atrophy on T1-weighted MRI, signal intensity ratios of the globus pallidus on T1-weighted MRI, whole blood manganese levels, and Wechsler Adult Intelligence Scale-Revised (WAIS-R) IQ parameters between alcoholics with and without liver cirrhosis, to investigate cognitive dysfunction, MRI findings and manganese levels in alcoholics. Pallidal hyperintensity was visually identified in 80% of alcoholic patients with liver cirrhosis. In addition, a significant correlation was seen between pallidal signal intensity (P.S.I.) ratio and blood manganese level. However, no significant correlations were found between pallidal signal intensity ratio and any of the WAIS-R parameters. These findings suggest that no direct connection exists between cognitive dysfunction and pallidal hyperintensity in alcoholic patients with liver cirrhosis. We confirmed that brain MRI in alcoholics could detect pallidal signal hyperintensity, suggesting severe liver dysfunction. In addition to diagnosis, brain MRI is useful for therapeutic psychoeducation to alcoholic patients with liver cirrhosis, visualizing the severe liver dysfunction. (author)

  3. Investigation of paramagnetic saturation in lanthanum manganese nitrate

    NARCIS (Netherlands)

    Flokstra, Jakob; Meijer, H.C.; Bots, G.J.C.; Verheij, W.A.; van der Marel, L.C.

    1973-01-01

    Paramagnetic saturation of lanthanum manganese nitrate, La2Mn3(NO3)12·24H2O, has been investigated at liquid He temperatures in a static as well as a dynamical way. With the aid of the molecular-field theory the Casimir and Du Pré dispersion and absorption curves are adapted explicitly to the

  4. Manganese Catalyzed Regioselective C–H Alkylation: Experiment and Computation

    KAUST Repository

    Wang, Chengming; Maity, Bholanath; Cavallo, Luigi; Rueping, Magnus

    2018-01-01

    A new efficient manganese-catalyzed selective C2-alkylation of indoles via carbenoid insertion has been achieved. The newly developed C-H functionalization protocol provides access to diverse products and shows good functional group tolerance. Mechanistic and computational studies support the formation of a Mn(CO)3 acetate complex as the catalytically active species.

  5. from Tailings Material of Ghana Manganese Company (GMC)

    African Journals Online (AJOL)

    user

    arrive at large scale secondary manganese sourcing by recycling from steel, beverage ... rpm, and the tangential flow of water through jets was at the rate of 210.10 ... the limitation of the machine‟s discharge pipes, frac- tions coarser than 20 ...

  6. THE STATE OF MANGANESE IN THE PHOTOSYNTHETIC APPARATUS. I. EXAFS STUDIES ON CHLOROPLASTS AND di-u-oxo BRIDGED di-MANGANESE MODEL COMPOUNDS

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, J. A.; Robertson, A. S.; Smith, J. P.; Thompson, A. C.; Thompson, A. C.; Klein, M. P.

    1980-11-01

    Extended X-ray Absorption Fine Structure (EXAFS) studies on the manganese contained in spinach chloroplasts and on certain di-u-oxo bridged manganese dimers of the form (X{sub 2}Mn)O{sub 2}(MnX{sub 2} (X=2,2'-bypyridine and 1,10-phenanthroline) are reported. From these studies, the manganese associated with photosynthetic oxygen evolution is suggested to occur as a bridged transition metal dimer with most likely another manganese. Extensive details on the analysis are included.

  7. Sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides

    Directory of Open Access Journals (Sweden)

    R.V. Smotraiev

    2016-05-01

    Full Text Available The actual problem of water supply in the world and in Ukraine, in particular, is a high level of pollution in water resources and an insufficient level of drinking water purification. With industrial wastewater, a significant amount of pollutants falls into water bodies, including suspended particles, sulfates, iron compounds, heavy metals, etc. Aim: The aim of this work is to determine the impact of aluminum and manganese ions additives on surface and sorption properties of zirconium oxyhydroxide based sorbents during their production process. Materials and Methods: The sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were prepared by sol-gel method during the hydrolysis of metal chlorides (zirconium oxychloride ZrOCl2, aluminum chloride AlCl3 and manganese chloride MnCl2 with carbamide. Results: The surface and sorption properties of sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were investigated. X-ray amorphous structure and evolved hydroxyl-hydrate cover mainly characterize the obtained xerogels. The composite sorbents based on xerogels of zirconium oxyhydroxide doped with aluminum oxyhydroxide (aS = 537 m2/g and manganese oxyhydroxide (aS = 356 m2/g have more developed specific surface area than single-component xerogels of zirconium oxyhydroxide (aS = 236 m2/g and aluminum oxyhydroxide (aS = 327 m2/g. The sorbent based on the xerogel of zirconium and manganese oxyhydroxides have the maximum SO42--ions sorption capacity. It absorbs 1.5 times more SO42–-ions than the industrial anion exchanger AN-221. The sorbents based on xerogels of zirconium oxyhydroxide has the sorption capacity of Fe3+-ions that is 1.5…2 times greater than the capacity of the industrial cation exchanger KU-2-8. The Na+-ions absorption capacity is 1.47…1.56 mmol/g for each sorbent. Conclusions: Based on these data it can be concluded that the proposed method is effective for sorbents production based on

  8. Selenium protects neonates against neurotoxicity from prenatal exposure to manganese.

    Directory of Open Access Journals (Sweden)

    Xin Yang

    Full Text Available Manganese (Mn exposure can affect brain development. Whether Selenium (Se can protect neonates against neurotoxicity from Mn exposure remains unclear. We investigated this issue in 933 mother-newborn pairs in Shanghai, China, from 2008 through 2009. Umbilical cord serum concentrations of Mn and Se were measured and Neonatal Behavioral Neurological Assessment (NBNA tests were conducted. The scores <37 were defined as the low NBNA. The median concentrations of cord serum Mn and Se were 4.0 µg/L and 63.1 µg/L, respectively. After adjusting for potential confounders, the interaction between Se and Mn was observed. Cord blood Mn levels had different effects on NBNA scores stratified by different cord blood Se levels. With Se

  9. Efficient and selective N-alkylation of amines with alcohols catalysed by manganese pincer complexes

    Science.gov (United States)

    Elangovan, Saravanakumar; Neumann, Jacob; Sortais, Jean-Baptiste; Junge, Kathrin; Darcel, Christophe; Beller, Matthias

    2016-01-01

    Borrowing hydrogen (or hydrogen autotransfer) reactions represent straightforward and sustainable C–N bond-forming processes. In general, precious metal-based catalysts are employed for this effective transformation. In recent years, the use of earth abundant and cheap non-noble metal catalysts for this process attracted considerable attention in the scientific community. Here we show that the selective N-alkylation of amines with alcohols can be catalysed by defined PNP manganese pincer complexes. A variety of substituted anilines are monoalkylated with different (hetero)aromatic and aliphatic alcohols even in the presence of other sensitive reducible functional groups. As a special highlight, we report the chemoselective monomethylation of primary amines using methanol under mild conditions. PMID:27708259

  10. Manganese-Catalyzed Aminomethylation of Aromatic Compounds with Methanol as a Sustainable C1 Building Block.

    Science.gov (United States)

    Mastalir, Matthias; Pittenauer, Ernst; Allmaier, Günter; Kirchner, Karl

    2017-07-05

    This study represents the first example of a manganese-catalyzed environmentally benign, practical three-component aminomethylation of activated aromatic compounds including naphtols, phenols, pyridines, indoles, carbazoles, and thiophenes in combination with amines and MeOH as a C1 source. These reactions proceed with high atom efficiency via a sequence of dehydrogenation and condensation steps which give rise to selective C-C and C-N bond formations, thereby releasing hydrogen and water. A well-defined hydride Mn(I) PNP pincer complex, recently developed in our laboratory, catalyzes this process in a very efficient way, and a total of 28 different aminomethylated products were synthesized and isolated yields of up to 91%. In a preliminary study, a related Fe(II) PNP pincer complex was shown to catalyze the methylation of 2-naphtol rather than its aminomethylation displaying again the divergent behavior of isoelectronic Mn(I) and Fe(II) PNP pincer systems.

  11. Electron-tunneling observation of local excited states in manganese-doped indium

    International Nuclear Information System (INIS)

    Tsang, J.; Ginsberg, D.M.

    1980-01-01

    We have measured the electron-tunneling characteristics of a dilute indium-manganese alloy. Well-defined structure was observed, corresponding to a band of local excited states within the energy gap. The measurements were made on two samples, and were quantitatively compared with the theory of Shiba and of Rusinov. We obtained good agreement of the tunneling data with the theory by taking into account only s-wave scattering of conduction electrons from the magnetic-impurity atoms. Even better agreement was obtained by including p- and d-wave scattering. Only by including these higher partial waves could we account for the magnitude of the observed depression of the transition temperature. The phase shifts used are in good agreement with band-theory values calculated recently

  12. The evolutionarily conserved protein PHOTOSYNTHESIS AFFECTED MUTANT71 is required for efficient manganese uptake at the thylakoid membrane in Arabidopsis

    DEFF Research Database (Denmark)

    Schneider, Anja; Steinberger, Iris; Herdean, Andrei

    2016-01-01

    In plants, algae, and cyanobacteria, photosystem II (PSII) catalyzes the light-driven oxidation of water. The oxygen-evolving complex of PSII is a Mn4CaO5 cluster embedded in a well-defined protein environment in the thylakoid membrane. However, transport of manganese and calcium into the thylako...... was restored by supplementation with Mn2+, but not Ca2+. Furthermore, PAM71 suppressed the Mn2+-sensitive phenotype of the yeast mutant Δpmr1. Therefore, PAM71 presumably functions in Mn2+ uptake into thylakoids to ensure optimal PSII performance....

  13. Methylphenidate alleviates manganese-induced impulsivity but not distractibility.

    Science.gov (United States)

    Beaudin, Stephane A; Strupp, Barbara J; Uribe, Walter; Ysais, Lauren; Strawderman, Myla; Smith, Donald R

    2017-05-01

    Recent studies from our lab have demonstrated that postnatal manganese (Mn) exposure in a rodent model can cause lasting impairments in fine motor control and attention, and that oral methylphenidate (MPH) treatment can effectively treat the dysfunction in fine motor control. However, it is unknown whether MPH treatment can alleviate the impairments in attention produced by Mn exposure. Here we used a rodent model of postnatal Mn exposure to determine whether (1) oral MPH alleviates attention and impulse control deficits caused by postnatal Mn exposure, using attention tasks that are variants of the 5-choice serial reaction time task, and (2) whether these treatments affected neuronal dendritic spine density in the medial prefrontal cortex (mPFC) and dorsal striatum. Male Long-Evans rats were exposed orally to 0 or 50Mn/kg/d throughout life starting on PND 1, and tested as young adults (PND 107-115) on an attention task that specifically tapped selective attention and impulse control. Animals were treated with oral MPH (2.5mg/kg/d) throughout testing on the attention task. Our findings show that lifelong postnatal Mn exposure impaired impulse control and selective attention in young adulthood, and that a therapeutically relevant oral MPH regimen alleviated the Mn-induced dysfunction in impulse control, but not selective attention, and actually impaired focused attention in the Mn group. In addition, the effect of MPH was qualitatively different for the Mn-exposed versus control animals across a range of behavioral measures of inhibitory control and attention, as well as dendritic spine density in the mPFC, suggesting that postnatal Mn exposure alters catecholaminergic systems modulating these behaviors. Collectively these findings suggest that MPH may hold promise for treating the behavioral dysfunction caused by developmental Mn exposure, although further research is needed with multiple MPH doses to determine whether a dose can be identified that ameliorates the

  14. Fluxes of dissolved aluminum and manganese to the Weddell Sea and indications for manganese co-limitation

    NARCIS (Netherlands)

    Middag, R.; de Baar, H.J.W.; Klunder, M.B.; Laan, P.

    2013-01-01

    The trace metals aluminum (Al) and manganese (Mn) were studied in the Weddell Sea in March 2008. Concentrations of dissolved Al ([Al]) were slightly elevated (0.23-0.35 nmol L-1) in the surface layer compared to the subsurface minimum (0.07-0.21 nmol L-1) observed in the winter water. Atmospheric

  15. Preparation and performance of manganese-oxide-coated zeolite for the removal of manganese-contamination in groundwater.

    Science.gov (United States)

    Lyu, Cong; Yang, Xuejiao; Zhang, Shengyu; Zhang, Qihui; Su, Xiaosi

    2017-12-29

    A promising and easily prepared catalytic filler media, manganese-oxide-coated zeolite (MOCZ), for the removal of Mn (II) contamination in groundwater was studied. The optimal condition for MOCZ preparation was given as follows: acid activation of zeolite with 5% HCl mass percent for 12 h, then soaking of acid-activated zeolite with 7% KMnO 4 mass percent for 8 h, and finally calcination at 300°C for 5 h. Acid activation significantly enlarged the specific surface area of the zeolite (>79 m 2  g -1 ), subsequently enhancing the coating of manganese oxides onto the surface of the zeolite. This was further supported by the manganese-to-zeolite ratio (γ Mn ) and Energy dispersive analysis-mapping. The γ Mn was over 12.26 mg Mn g -1 zeolite, representing more active sites for the adsorption and catalytic-oxidation of Mn (II). As such, great performance of Mn (II) removal by MOCZ was obtained in the filter experiment. An estimated 98-100% removal efficiency of Mn (II) was achieved in a greatly short startup time (only 2 h). During the filtration process, newborn flocculent manganese oxides with a mixed-valence of manganese (Mn (II) and Mn (IV)) were generated on the MOCZ surface, further facilitating the adsorption and catalytic-oxidation of Mn (II). The filter with MOCZ as adsorbent had a great performance on the Mn (II) removal in a wide range of hydraulic retention time (HRT) (4-40 min), particularly in a short HRT. Besides, the filter prolonged the filtration period (60 days), which would significantly reduce the frequency of backwash. Thus, it could be concluded that MOCZ prepared in this study showed a good performance in terms of Mn (II) removal in waterworks, especially small waterworks in the villages/towns.

  16. Irradiation alternative method of manganese sulfate solution by a Pu-Be source for efficiency measurements; Metodo alternativo de irradiacao da solucao de sulfato de manganes por uma fonte de Pu-Be para medicoes de eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner, E-mail: fellipess@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO{sub 4} solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  17. Manganese Deposits in the Artillery Mountains Region, Mohave County, Arizona

    Science.gov (United States)

    Lasky, S.G.; Webber, B.N.

    1944-01-01

    The manganese deposits of the Artillery Mountains region lie within an area of about 25 square miles between the Artillery and Rawhide Mountains, on the west side of the Bill Williams River in west-central Arizona. The richest croppings are on the northeast side of this area, among the foothills of the Artillery Mountains. They are 6 to 10 miles from Alamo. The nearest shipping points are Congress, about 50 miles to the east, and Aguila, about 50 miles to the southeast. The principal manganese deposits are part of a sequence of alluvial fan and playa material, probably of early Pliocene age, which were laid down in a fault basin. They are overlain by later Pliocene (?) basalt flows and sediments and by Quaternary basalt and alluvium. The Pliocene (?) rocks are folded into a shallow composite S1ncline ttat occupies the valley between the Artillery and Rawhide Mountains, and the folded rocks along either side of the valley, together with the overlying Quaternary basalt, are broken by faults that have produced a group of horsts, grabens, and step-fault blocks. The manganiferous beds, lie at two zones, 750 to 1,000 feet apart stratigraphically, each of which is locally as much as 300 to 400 feet thick. The main, or upper, zone contains three kinds of ore - sandstone ore, clay ore, and 'hard' ore. The sandstone and clay ores differ from the associated barren sandstone and clay, with which they are interlayered and into which they grade, primarily in containing a variable proportion of amorphous manganese oxides, besides iron oxides and clayey material such as are present in the barren beds. The 'hard' ore is sandstone that has been impregnated with opal and calcite and in which the original amorphous manganese oxides have been largely converted to psilomelane and manganite. The average manganese content of the sandstone and clay ores is between 3 and 4 percent and that of the 'hard' ore is between 6 and 7 percent. The ore contains an average of 3 percent of iron, 0

  18. Relationships Between Essential Manganese Biology and Manganese Toxicity in Neurological Disease.

    Science.gov (United States)

    Pfalzer, Anna C; Bowman, Aaron B

    2017-06-01

    Manganese (Mn) is critical for neurodevelopment but also has been implicated in the pathophysiology of several neurological diseases. We discuss how Mn requirements intersect with Mn biology and toxicity, and how these requirements may be altered in neurological disease. Furthermore, we discuss the emerging evidence that the level of Mn associated with optimal overall efficiency for Mn biology does not necessarily coincide with optimal cognitive outcomes. Studies have linked Mn exposures with urea cycle metabolism and autophagy, with evidence that exposures typically neurotoxic may be able to correct deficiencies in these processes at least short term. The line between Mn-dependent biology and toxicity is thus blurred. Further, new work suggests that Mn exposures correlating to optimal cognitive scores in children are associated with cognitive decline in adults. This review explores relationships between Mn-dependent neurobiology and Mn-dependent neurotoxicity. We propose the hypothesis that Mn levels/exposures that are toxic to some biological processes are beneficial for other biological processes and influenced by developmental stage and disease state.

  19. The multiple Dirichlet product and the multiple Dirichlet series

    OpenAIRE

    Onozuka, Tomokazu

    2016-01-01

    First, we define the multiple Dirichlet product and study the properties of it. From those properties, we obtain a zero-free region of a multiple Dirichlet series and a multiple Dirichlet series expression of the reciprocal of a multiple Dirichlet series.

  20. Energy transfer mechanism between manganese and neodymium

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, R [Department of Physics, Government Raza Post-Graduate College, Rampur 244901, U.P., India

    1977-01-01

    The mechanism of energy transfer between Mn/sup 2 +/ ..-->.. Nd/sup 3 +/ in barium borate glass has been investigated. The change in emission intensities and lifetimes of Mn/sup 2 +/ (donor) due to the presence of Nd/sup 3 +/ (acceptor) are observed. It has been concluded that the mechanism of energy transfer involves a nonradiative resonance process. The electrostatic multiple interaction responsible for the transfer is dipole-dipole in nature.

  1. Adsorption of selenium by amorphous iron oxyhydroxide and manganese dioxide

    Science.gov (United States)

    Balistrieri, L.S.; Chao, T.T.

    1990-01-01

    This work compares and models the adsorption of selenium and other anions on a neutral to alkaline surface (amorphous iron oxyhydroxide) and an acidic surface (manganese dioxide). Selenium adsorption on these oxides is examined as a function of pH, particle concentration, oxidation state, and competing anion concentration in order to assess how these factors might influence the mobility of selenium in the environment. The data indicate that 1. 1) amorphous iron oxyhydroxide has a greater affinity for selenium than manganese dioxide, 2. 2) selenite [Se(IV)] adsorption increases with decreasing pH and increasing particle concentration and is stronger than selenate [Se(VI)] adsorption on both oxides, and 3. 3) selenate does not adsorb on manganese dioxide. The relative affinity of selenate and selenite for the oxides and the lack of adsorption of selenate on a strongly acidic surface suggests that selenate forms outer-sphere complexes while selenite forms inner-sphere complexes with the surfaces. The data also indicate that the competition sequence of other anions with respect to selenite adsorption at pH 7.0 is phosphate > silicate > molybdate > fluoride > sulfate on amorphous iron oxyhydroxide and molybdate ??? phosphate > silicate > fluoride > sulfate on manganese dioxide. The adsorption of phosphate, molybdate, and silicate on these oxides as a function of pH indicates that the competition sequences reflect the relative affinities of these anions for the surfaces. The Triple Layer surface complexation model is used to provide a quantitative description of these observations and to assess the importance of surface site heterogeneity on anion adsorption. The modeling results suggest that selenite forms binuclear, innersphere complexes with amorphous iron oxyhydroxide and monodentate, inner-sphere complexes with manganese dioxide and that selenate forms outer-sphere, monodentate complexes with amorphous iron oxyhydroxide. The heterogeneity of the oxide surface sites

  2. Iron and manganese oxides modified maize straw to remove tylosin from aqueous solutions.

    Science.gov (United States)

    Yin, Yongyuan; Guo, Xuetao; Peng, Dan

    2018-08-01

    Maize straw modified by iron and manganese oxides was synthesized via a simple and environmentally friendly method. Three maize straw materials, the original maize straw, maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides, were detected by SEM, BET, XPS, XRD and FTIR. The results showed that maize straw was successfully modified and maize straw modified by iron and manganese oxides has a larger surface area than MS. According to the experimental data, the sorption trend could conform to the pseudo-second-order kinetic model well, and the sorption ability of tylosin on sorbents followed the order of original maize straw oxides iron and manganese oxides. The study indicated that manganese oxides and iron-manganese oxides could significantly enhance the sorption capacity of original maize straw. The sorption isotherm data of tylosin on original maize straw fit a linear model well, while Freundlich models were more suitable for maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides. The pH, ionic strength and temperature can affect the sorption process. The sorption mechanisms of tylosin on iron and manganese oxides modified maize straw were attribute to the surface complexes, electrostatic interactions, H bonding and hydrophobic interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Manganese oxide-based multifunctionalized mesoporous silica nanoparticles for pH-responsive MRI, ultrasonography and circumvention of MDR in cancer cells.

    Science.gov (United States)

    Chen, Yu; Yin, Qi; Ji, Xiufeng; Zhang, Shengjian; Chen, Hangrong; Zheng, Yuanyi; Sun, Yang; Qu, Haiyun; Wang, Zheng; Li, Yaping; Wang, Xia; Zhang, Kun; Zhang, Linlin; Shi, Jianlin

    2012-10-01

    Nano-biotechnology has been introduced into cancer theranostics by engineering a new generation of highly versatile hybrid mesoporous composite nanocapsules (HMCNs) for manganese-based pH-responsive dynamic T(1)-weighted magnetic resonance imaging (MRI) to efficiently respond and detect the tumor acidic microenvironment, which was further integrated with ultrasonographic function based on the intrinsic unique hollow nanostructures of HMCNs for potentially in vitro and in vivo dual-modality cancer imaging. The manganese oxide-based multifunctionalization of hollow mesoporous silica nanoparticles was achieved by an in situ redox reaction using mesopores as the nanoreactors. Due to the dissolution nature of manganese oxide nanoparticles under weak acidic conditions, the relaxation rate r(1) of manganese-based mesoporous MRI-T(1) contrast agents (CAs) could reach 8.81 mM(-1)s(-1), which is a 11-fold magnitude increase compared to the neutral condition, and is almost two times higher than commercial Gd(III)-based complex agents. This is also the highest r(1) value ever reported for manganese oxide nanoparticles-based MRI-T(1) CAs. In addition, the hollow interiors and thin mesoporous silica shells endow HMCNs with the functions of CAs for efficient in vitro and in vivo ultrasonography under both harmonic- and B-modes. Importantly, the well-defined mesopores and large hollow interiors of HMCNs could encapsulate and deliver anticancer agents (doxorubicin) intracellularly to circumvent the multidrug resistance (MDR) of cancer cells and restore the anti-proliferative effect of drugs by nanoparticle-mediated endocytosis process, intracellular drug release and P-gp inhibition/ATP depletion in cancer cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Manganese oxide nanowires, films, and membranes and methods of making

    Science.gov (United States)

    Suib, Steven Lawrence [Storrs, CT; Yuan, Jikang [Storrs, CT

    2008-10-21

    Nanowires, films, and membranes comprising ordered porous manganese oxide-based octahedral molecular sieves, and methods of making, are disclosed. A single crystal ultra-long nanowire includes an ordered porous manganese oxide-based octahedral molecular sieve, and has an average length greater than about 10 micrometers and an average diameter of about 5 nanometers to about 100 nanometers. A film comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is stacked on a surface of a substrate, wherein the nanowires of each layer are substantially axially aligned. A free standing membrane comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is aggregately stacked, and wherein the nanowires of each layer are substantially axially aligned.

  5. Influence of metallic additives on manganese ferrites sintering

    Science.gov (United States)

    Shevelev, S. A.; Luchnikov, P. A.; Yarullina, A. R.

    2018-01-01

    Influence of cuprum nanopowder additive received by electric explosion on the process of manganese ferrites MgFe2O4 consolidating at thermal sintering was researched by dilatometry method. Cuprum nanopowder at a rate of 5 mass % was added into the original commercial-grade powder of manganese ferrite MgFe2O4. Powder mixture was numerously blended with screening for better blending before pressing. Powder compacts were formed by cold one-axle static pressing. It was proved that introduction of cuprum additive caused shrinkage increase at final heating stage. There was abnormal compact enlarging at sintering in the air at isothermal stage; the specified process was not observed in vacuum. This difference can be explained by changes in conditions of gaseous discharge from volume of pores.

  6. Uranium in Pacific deep-sea sediments and manganese nodules

    International Nuclear Information System (INIS)

    Kunzendorf, H.; Plueger, W.L.; Friedrich, G.H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water into the Fe-rich (ferromanganese mineral phase MnO 2 . Enrichment of U and Fe in nodules from the northwestern slopes of two submarine hills (U between 6 and 9 ppm) in the equatorial nodule belt is thought to be caused by directional bottom water flow creating elevated oxygenized conditions in areas opposed to the flow. Economically important nodule deposits from the nodule belt and the Peru Basin have generally low U contents, between 3 and 5 ppm. Insignificant resources of U of about 4 x 10 5 in the Pacific manganese nodules are estimated. (orig.)

  7. Advanced manganese oxide material for rechargeable lithium cells

    Energy Technology Data Exchange (ETDEWEB)

    Atwater, Terrill B.; Salkind, Alvin J. [Rutgers University, Piscataway, NJ (United States)

    2006-11-22

    A family of potassium-doped manganese oxide materials were synthesized with the stoichiometric formula Li{sub 0.9-X}K{sub X}Mn{sub 2}O{sub 4}, where X=0.0-0.25 and evaluated for their viability as a cathode material for a rechargeable lithium battery. A performance maximum was found at X=0.1 where the initial specific capacity for the lithium-potassium-doped manganese dioxide electrochemical couple was 130mAhg{sup -1} of active cathode material. The discharge capacity of the system was maintained through 90 cycles (95% initial capacity). Additionally, the capacity was maintained at greater than 90% initial discharge through 200 cycles. Other variants demonstrated greater than 75% initial discharge through 200 cycles at comparable capacity. (author)

  8. Charpy impact behavior of manganese-stabilized martensitic steels

    International Nuclear Information System (INIS)

    Hu, W.L.; Gelles, D.S.

    1986-05-01

    Tests were conducted to evaluate the irradiation-induced shift in ductile-to-brittle transition behavior of two manganese stabilized martensitic steels. Miniature Charpy specimens were fabricated from two heats of steel similar in composition to HT-9 but with 0.1% C and Mn contents ranging from 3.3 to 6.6.%. The 3.3% Mn steel showed a transition temperature similar to that of HT-9 in both the unirradiated condition and in specimens irradiated to 11.3 dpa. The steel containing 6.6% Mn exhibited a higher transition temperature after irradiation than the steel containing 3.3% Mn. The upper shelf energy (USE) after irradiation for the manganese stabilized alloys was much higher than for HT-9. 6 refs., 3 figs., 2 tabs

  9. In Situ Atom Probe Deintercalation of Lithium-Manganese-Oxide.

    Science.gov (United States)

    Pfeiffer, Björn; Maier, Johannes; Arlt, Jonas; Nowak, Carsten

    2017-04-01

    Atom probe tomography is routinely used for the characterization of materials microstructures, usually assuming that the microstructure is unaltered by the analysis. When analyzing ionic conductors, however, gradients in the chemical potential and the electric field penetrating dielectric atom probe specimens can cause significant ionic mobility. Although ionic mobility is undesirable when aiming for materials characterization, it offers a strategy to manipulate materials directly in situ in the atom probe. Here, we present experimental results on the analysis of the ionic conductor lithium-manganese-oxide with different atom probe techniques. We demonstrate that, at a temperature of 30 K, characterization of the materials microstructure is possible without measurable Li mobility. Also, we show that at 298 K the material can be deintercalated, in situ in the atom probe, without changing the manganese-oxide host structure. Combining in situ atom probe deintercalation and subsequent conventional characterization, we demonstrate a new methodological approach to study ionic conductors even in early stages of deintercalation.

  10. Methylcyclopentadienyl manganese tricarbonyl (MMT), plant uptake and effects on metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A.R.; Lytle, C.M.; Stone, R.L.; Smith, B.N [Department of Botany and Range Science, Brigham Young University, Provo (United States); Hansen, L.D. [Department of Chemistry and Biochemistry, Brigham Young University, Provo (United States)

    2000-04-01

    In the USA and Canada, methylcyclopentadienyl manganese (MMT) is currently added to gasoline to replace tetraethyl lead as an antiknock fuel additive. Manganese concentrations in roadside soil and plants are increasing and correlated with distance from the roadway, traffic volume, plant type, and microhabitat. Radish (Raphanus sativus L.) seedlings were treated for either five or thirty-five days with different levels of manganous chloride (0-1000ppm). Metabolic heat rates (q) and respiration rates (R{sub CO{sub 2}}), measured calorimetrically, indicated severe stress at Mn concentrations between 10 and 100ppm and at temperatures above 20C. Predicted growth rates (R{sub SG}) also decreased in these circumstances.

  11. The separation of trace elements in manganese dioxide

    International Nuclear Information System (INIS)

    Jones, E.A.; Dixon, K.

    1981-01-01

    Separations from manganese are discribed for (a)Al(III), Mo(VI), V(V), and Ti(IV), and (b)trace elements in general. In the first separation, a combined anion-cation exchange, the oxalate complexes are absorbed onto the anionic BIO.RAD 1-X8 resin. V(V) and Al(III) are then eluted into a cation-exchange column from which they are eluted successively, Mo(VI) and Ti(IV) then being eluted from the anionic resin. In the second separation, up to 2g of manganese is absorbed onto BIO.RAD AG 50W-X8 resin, from which V(V) is eluted with dilute hydrochloric acid prior to the elution of Co(II), Cu(II), Zn(II), Cd(II), Fe(III), As(III), Sb(III), Mo(VI), W(VI), and Sn(II) with a mixture of 1 M hydrochloric acid, 80 per cent acetone, and 0,1 per cent hydrogen peroxide. Mn(11) is eluted next with a mixture of 0,75M hydrochloric acid and 90 per cent acetone, after which the remaining cations are eluted with 4M hydrochloric acid. Satisfactory recoveries ranging from 0,8 to 60 mg/l were obtained for 18 of the 21 elements tested. After concentration by evaporation, final measurements were made by the use of atomic-absorption spectrophotometry, or direct-reading spectrometry with excitation from an inductively coupled plasma source. Comparative results were obtained with atomic-absorption procedures where the manganese was not separated. However, the separation procedure can reduce the time required for analysis by the direct method because it limits the number of dilutions necessary and eliminates the need for the use of the method of additions to compensate for interferences from manganese

  12. Rhenium and Manganese-Catalyzed Selective Alkenylation of Indoles

    KAUST Repository

    Wang, Chengming

    2018-04-06

    An efficient rhenium‐catalyzed regioselective C‐H bond alkenylation of indoles is reported. The protocol operates well for internal as well as terminal alkynes, affording products in good to excellent yields. Furthermore, a manganese catalyzed, acid free, regioselective C2‐alkenylation of indoles with internal alkynes is described. The directing groups can be easily removed after the reaction and the resulting products can be used as valuable building blocks for the synthesis of diverse heterocyclic compounds.

  13. Swelling behavior of manganese-bearing AISI 216 steel

    International Nuclear Information System (INIS)

    Gelles, D.S.; Garner, F.A.

    1984-01-01

    The inclusion of 8.5 wt % manganese in AISI 216 does not appear to alter the swelling behavior from that found to be typical of austenitic alloys with comparable levels of other austentite-stabilizing elements. The swelling in AISI 216 in EBR-II is quite insensitive to irradiation temperature in the range 400-650 0 C. Microscopy reveals that this may arise from the low level of precipitation that occurs in the alloy

  14. Determination of manganese in blood by neutron activation analysis

    International Nuclear Information System (INIS)

    Kocsis, E.; Kovats, M.; Molnar, M.

    1981-01-01

    A new method has been elaborated: the manganese content of a blood sample was precipitated by H 2 O 2 , and analysed by neutron activation analysis. The mean value was 2.67x10 -8 g/g in men, 3.25x10 -8 g/g in women and 3.57x10 -8 g/g in men working as welders for several years. (L.E.)

  15. Processes of formation of ferromanganese manganese nodules and crusts

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.

    oceanic cycling assume importance in view of the fact that it is the tenth most abundant element in the Earth’s crust. It occurs in two valency states whose stability lies within the limits of the natural importance. Oxides of manganese also have high... cations. Thus, both can migrate under the influence of redox gradients. Fractionation between this pair can probably occur in anoxic and high temperature conditions. In balancing the Mn between different oceanic reservoirs, Goldschmidt in 1954 has...

  16. Manganese: Recent advances in understanding its transport and neurotoxicity

    International Nuclear Information System (INIS)

    Aschner, Michael; Guilarte, Tomas R.; Schneider, Jay S.; Zheng Wei

    2007-01-01

    The present review is based on presentations from the meeting of the Society of Toxicology in San Diego, CA (March 2006). It addresses recent developments in the understanding of the transport of manganese (Mn) into the central nervous system (CNS), as well as brain imaging and neurocognitive studies in non-human primates aimed at improving our understanding of the mechanisms of Mn neurotoxicity. Finally, we discuss potential therapeutic modalities for treating Mn intoxication in humans

  17. Purification of arsenic contaminated ground water using hydrated manganese dioxide

    International Nuclear Information System (INIS)

    Raje, N.; Swain, K.K.

    2002-01-01

    An analytical methodology has been developed for the separation of arsenic from ground water using inorganic material in neutral medium. The separation procedure involves the quantitative retention of arsenic on hydrated manganese dioxide, in neutral medium. The validity of the separation procedure has been checked by a standard addition method and radiotracer studies. Neutron activation analysis (NAA), a powerful measurement technique, has been used for the quantitative determination of arsenic. (author)

  18. Rhenium and Manganese-Catalyzed Selective Alkenylation of Indoles

    KAUST Repository

    Wang, Chengming; Rueping, Magnus

    2018-01-01

    An efficient rhenium‐catalyzed regioselective C‐H bond alkenylation of indoles is reported. The protocol operates well for internal as well as terminal alkynes, affording products in good to excellent yields. Furthermore, a manganese catalyzed, acid free, regioselective C2‐alkenylation of indoles with internal alkynes is described. The directing groups can be easily removed after the reaction and the resulting products can be used as valuable building blocks for the synthesis of diverse heterocyclic compounds.

  19. Gold, iron and manganese in central Amapá, Brazil

    Directory of Open Access Journals (Sweden)

    Wilson Scarpelli

    Full Text Available ABSTRACT: Greenstone belts with deposits of gold, iron and manganese are common in the Paleoproterozoic Maroni-Itacaiunas Tectonic Province of the Guiana Shield. In Brazil, in the State of Amapá and northwest of Pará, they are represented by the Vila Nova Group, constituted by a basal unit of metabasalts, covered by metasediments of clastic and chemical origin. The basal metasediments, the Serra do Navio Formation, are made of a cyclothem with lenses of manganese marbles at the top of each cycle. Under the intense weathering of the Amazon, these lenses were oxidized to large deposits of high-grade manganese oxides. The exploitation of these oxides left behind the manganese carbonates and low-grade oxides. The overlaying Serra da Canga Formation presents a calcium and magnesium domain grading to an iron domain with banded silicate and oxide iron formations, mined for iron ores. Overlapping structures and superposed metamorphic crystallizations indicate two phases of dynamothermal metamorphism, the first one with axis to north-northeast and the second one to northwest, with an intermediate phase of thermal metamorphism related to syntectonic granitic intrusions. Shears oriented north-south, possibly formed during the first dynamothermal metamorphism and reactivated in the second, are ideal sites for hydrothermalism and gold mineralization, which is greater when occurs in iron formation and carbonate-bearing rocks, as it happened at the Tucano mine. Layered mafic-ultramafic intrusions in the greenstones represent a potential for chromite and platinum group elements. Pegmatites are source of cassiterite and tantalite exploited from alluvial deposits.

  20. Manganese accumulation in hair and teeth as a biomarker of manganese exposure and neurotoxicity in rats.

    Science.gov (United States)

    Liang, Guiqiang; Zhang, Li'e; Ma, Shuyan; Lv, Yingnan; Qin, Huiyan; Huang, Xiaowei; Qing, Li; Li, Qin; Chen, Kangcheng; Xiong, Feng; Ma, Yifei; Nong, Jie; Yang, Xiaobo; Zou, Yunfeng

    2016-06-01

    Manganese (Mn) is an essential trace element to humans. However, excessive Mn causes cognitive impairment resulting from injury to the central nervous system within the hippocampus. No ideal biomarker is currently available for evaluating Mn exposure and associated neurotoxicity in the body. Hence, this study used Mn levels in the serum (MnS), teeth (MnT), and hair (MnH) as biomarkers for evaluating the association between Mn exposure and cognitive impairment in Mn-treated rats. A total of 32 male Sprague-Dawley rats were randomly divided into four groups, received 0, 5, 10, and 20 mg/(kg day) of MnCl2·4H2O for 5 days a week for 18 weeks, respectively. Lifetime Mn cumulative dose (LMCD) was used to evaluate external Mn exposure. Hippocampus, serum, teeth, and hair specimens were collected from the rats for Mn determination by graphite furnace atomic absorption spectrometry. Learning and memory functions were assessed using the Morris water maze test. Results showed that chronic Mn exposure increased the hippocampus (MnHip), MnS, MnT, and MnH levels, as well as impaired learning and memory function in rats. MnHip, MnT, and MnH levels were positively correlated with LMCD (r = 0.759, r = 0.925, and r = 0.908, respectively; p  0.05). Thus, MnT and MnH detected long-term low-dose Mn exposure. These parameters can be reliable biomarkers for Mn exposure and associated neurotoxicity in Mn-treated rats.

  1. Preparation of Baking-Free Brick from Manganese Residue and Its Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2013-01-01

    Full Text Available The increasing amount of waste residue produced during the electrolytic preparation process of manganese has nowadays brought about serious environmental problems. The research on utilization of manganese slag has been a hot spot around the world. The utilization of manganese slag is not only environment friendly, but also economically feasible. In the current work, a summarization of the main methods to produced building materials from manganese slag materials was given. Baking-free brick, a promising building material, was produced from manganese slag with the addition of quicklime and cement. The physical properties, chemical composition, and mechanical performances of the obtained samples were measured by several analyses and characterization methods. Then the influence of adding materials and molding pressure during the preparation of baking-free brick samples on their compressive strength properties was researched. It is concluded that the baking-free brick prepared from manganese residue could have excellent compressive strength performance under certain formula.

  2. Sinterization of manganese ore tailings under argon atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Valduga, M.M.F.; Lima, F.; Lima, R.M.F. [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2014-07-01

    Manganese is an element widely used in Metallurgy, however the Brazilian reserves has low grade. The aim of this work was to obtain and characterize the sinters from manganese ore tailings. The fines (less than 400⧣) were calcinated (800°C - 3600s) and homogenized with activated charcoal (7 and 10%) and CaO (5 and 10%). The sintering were carried out at 1135, 1140 and 1145°C during 7200 and 14400s under argon atmosphere. The sintered products were characterized by EDS analysis, BET surface area, apparent density, X-rays diffraction and SEM/EDS. The surface area was 0.03m2/g. The alkali element present (potassium) justified the low melting point of waste (1140°C). Due to the chemical complexity of the tailings, several phases were characterized in the products: pores, silicates with high content of manganese in the matrix, other silicates with different proportions of Al, Mn, Mg and Ca, pure Fe, SiO2, etc. (author)

  3. Sinterization of manganese ore tailings under natural air

    Energy Technology Data Exchange (ETDEWEB)

    Lima, M.M.F.; Souza, L.G.P.R.M.F. [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2014-07-01

    The manganese ore has wide application in metallurgy. However, from each of three hundred concentrations found, only one can be seen as a deposit. The aim of this study was to obtain and characterize a sinter from manganese ore tailing. The tailing was milled, classified (<400 ⧣) and calcinated (800°C - 3600s). The mixture had 12% moisture, 7 and 9% of activated charcoal. After homogenization, the sintering were carried out at 1140, 1145 and 1150°C during 1800, 7200 and 14400s at natural air. The sintered products were characterized by EDS analysis, BET surface area, apparent density, X-rays diffraction and SEM/EDS. The mass loss was approximately 14% and 16% in the calcination and sintering, respectively, due to the elimination of volatile products and water. The main phases characterized: SiO2, silicate with high content of manganese in the matrix and other silicates with different proportions of Ti, Na, Mn, Mg and Ca. (author)

  4. Cyclic deformation and fatigue behaviors of Hadfield manganese steel

    Energy Technology Data Exchange (ETDEWEB)

    Kang, J. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Zhang, F.C., E-mail: zfc@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Long, X.Y. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Lv, B. [School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China)

    2014-01-03

    The cyclic deformation characteristics and fatigue behaviors of Hadfield manganese steel have been investigated by means of its ability to memorize strain and stress history. Detailed studies were performed on the strain-controlled low cycle fatigue (LCF) and stress-controlled high cycle fatigue (HCF). Initial cyclic hardening to saturation or peak stress followed by softening to fracture occurred in LCF. Internal stress made the dominant contribution to the fatigue crack propagation until failure. Effective stress evolution revealed the existence of C–Mn clusters with short-range ordering in Hadfield manganese steel and demonstrated that the interaction between C atoms in the C–Mn cluster and dislocation was essential for its cyclic hardening. The developing/developed dislocation cells and stacking faults were the main cyclic deformation microstructures on the fractured sample surface in LCF and HCF, which manifested that fatigue failure behavior of Hadfield manganese steel was induced by plastic deformation during strain-controlled or stress-controlled testing.

  5. Selective uptake of manganese in seawater by hybrid microcapsules

    International Nuclear Information System (INIS)

    Kuzumaki, Takenori; Yan, Wu; Mimura, Hitoshi; Niibori, Yuichi

    2008-01-01

    The selective separation and recovery of low concentrated elements in seawater are very important subjects for the advancement of environmental monitoring. Selective uptake of manganese from seawater was carried out by using two kinds of microcapsules (MCs) including activated carbon (AC) and insoluble tannin (T). The adsorbents, AC and T, having affinity for manganese, were enclosed into MCs (ACMS, TMC) by sol-gel method using matrices of biopolymer (calcium alginate gel polymer, CaALG). The uptake properties and selectivity of Mn 2+ (1 ppm) for MCs were examined by batch method. Relatively large uptake percentages of Mn 2+ above 80% were obtained within 1 h, and the uptake percentage above 80% was kept at pH 3-6. The uptake order was found to be T, AC, CaALG > ACMC, TMC. The uptake of Mn 2+ decreased with increasing Na + ion concentration. This tendency depends on the swelling property of CaALG; it tends to solate in the presence of highly concentrated Na + ions. The manganese ions were adsorbed on CaALG, ACMC and TMC from seawater containing 1,000 ppm Mn 2+ . ACMC and TMC had selectivity to Mn 2+ , and, especially, the matrices of CaALG also had an excellent uptake and selectivity properties. (author)

  6. Magnetic properties and morphology of manganese ferrite nanoparticles in glasses

    International Nuclear Information System (INIS)

    Edelman, I; Ivanova, O; Ivantsov, I; Velikanov, D; Petrakovskaja, E; Artemenko, A; Curély, J; Kliava, J; Zaikovskiy, V; Stepanov, S

    2011-01-01

    Static magnetization (SM), magnetic circular dichroism (MCD) and electron magnetic resonance (EMR) studies are reported of borate glasses 22.5 K 2 O-22.5 Al 2 O 3 -55 B 2 O 3 co-doped with iron and manganese oxides. In as-prepared glasses the paramagnetic ions usually are in diluted state; however, if the ratio of the iron and manganese oxides in the charge is 3/2, magnetic nanoparticles are found already in as-prepared glass. After additional thermal treatment all glasses show magnetic behaviour, MCD and EMR due to the presence of magnetic nanoparticles with characteristics close to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, their morphological characteristics are deduced: relatively broad size and shape distribution with average diameter of ca. 3-4 nm. The characteristic temperature-dependent shift of the apparent resonance field is explained by a strong temperature dependence of the magnetocrystalline anisotropy in the nanoparticles. The potassium-alumina-borate glasses containing magnetic nanoparticles represent a novel class of materials: t ransparent magnets . Indeed, they remain transparent in a part of visible and near infrared spectral range while showing magnetic and magneto-optical properties characteristic of magnetically ordered materials.

  7. Autoradiography of manganese: accumulation and retention in the pancreas

    International Nuclear Information System (INIS)

    Lyden, A.; Lindquist, N.G.; Larsson, B.S.

    1983-01-01

    By means of whole-body autoradiography, the general distribution of 54 MnCl 2 was studied in mice and a Marmoset monkey. High accumulation and retention were observed in the pancreas in both species. Gamma counting experiments in mice after a single intravenous injection of 54 MnCl 2 showed that the level in the pancreas exceeded that of the liver at all survival times (20 min. - 30 days). Also in the monkey, the concentration in the pancreas exceeded that of the liver, and the pancreas had the highest tissue/liver ratio of the organs measured at 24 hours after injection. The high uptake and long retention in the pancreas suggest that manganese is of importance for the pancreatic function but also that the pancreas may be a target organ for manganese toxicity. Positron tomography, using 11 C-labelled amino acids, has been found to be a promising diagnostic technique for the study of pancreatic disease. Positron emitting manganese isotopes may be worth further studies as possible agents for pancreatic imaging. (author)

  8. BUILDING MATERIALS AND PRODUCTS BASED ON SILICON MANGANESE SLAGS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-05-01

    Full Text Available Raising of problem. Currently of particular relevance was given to the matter of introduction in manufacture of building materials and products, resource-saving techniques and technologies; integrated use of raw materials and materials that prevent or significantly reduce their harmful impact on the environment. This allows you to recycle hundreds of thousands of tons of the fiery liquid slags of silicon manganese and to develop effective structural materials that can replace metals, non-metallic building materials of natural origin, concretes, cast stone, plastics and refractories. Purpose. The study of the structure and properties of building materials and products from electric furnace slag of silicon manganese. Conclusion. Slags from the smelting of silicon manganese are classified as acidic. Their lime factor is in the range of 0.47–0.52. The composition of the slag located in the heterogeneous region SiO2 near the line of separation of cristobalite spread to the crystallization of wollastonite, according to the ternary system MnO-CaO-SiO2, which in consideration of their stability, allows the development of technology of building materials (gravel, sand, granulated slag, etc. and products (foundation blocks, road slabs, containers for transportation and storage of hazardous waste, and others.

  9. Characterisation of chemically lithiated heat-treated electrolytic manganese dioxide

    International Nuclear Information System (INIS)

    Dose, Wesley M.; Lehr, Joshua; Donne, Scott W.

    2012-01-01

    Highlights: ► Manganese oxides are a promising cathode material for lithium ion batteries. Here we examine the structural and morphological changes that occur upon reduction, and assess its impact on material performance. ► Upon reduction, MnO 2 transforms into LiMn 2 O 4 , which is subsequently reduced to Li 2 Mn 2 O 4 . ► Significant morphological changes occur, particularly to the material porosity. ► This transformation for MnO 2 has not been reported previously. -- Abstract: Heat treated manganese dioxide is partially lithiated using butyl-lithium to determine the changes in crystal structure, chemical composition and morphology upon reduction, as a means of simulating its discharge behaviour in a non-aqueous battery cathode. As reduction proceeds, and lithium ions are inserted into the heat treated electrolytic manganese dioxide (EMD) structure, the material undergoes a phase transition to LiMn 2 O 4 . This new phase is further reduced to Li 2 Mn 2 O 4 . Reduction initially results in a 56% decrease in the surface area of the material; however, at higher degrees of reduction a slight increase in this value is observed, as a consequence of the strain placed on the lattice through continued lithium insertion.

  10. Dimensional crossover in manganese based analogues of iron pnictides

    Energy Technology Data Exchange (ETDEWEB)

    Zingl, Manuel; Assmann, Elias; Aichhorn, Markus [University of Technology, Institute of Theoretical Physics and Computational Physics, Graz (Austria)

    2016-07-01

    The manganese pnicitides BaMn{sub 2}As{sub 2} and LaOMnAs crystallize in the same structure as the extensively studied iron pnictide high-temperature superconductors BaFe{sub 2}As{sub 2} and LaOFeAs. In contrast to the d{sup 6} configuration of the iron systems, the manganese d-shell is only half-filled (d{sup 5}). As a consequence, electronic correlations are much stronger, placing these compounds at the verge of the Mott metal-insulator transition. In this region of the phase diagram materials are prone to enhanced magnetism, apparent in the remarkably high Neel temperature of 625 K for BaMn{sub 2}As{sub 2}. We demonstrate that the experimentally observed differences in the Neel temperatures, the band gap, and the optical properties of the manganese compounds under consideration can be traced back to their effective dimensionality. Our fully charge self-consistent DFT+DMFT calculations show excellent agreement with experiments, especially measured optical spectra.

  11. Iron and manganese removal from a groundwater supply

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, W.; Seifert, K.; Kasch, O.K. (Arber Richard P. Associates, Inc., Denver, CO (USA))

    1988-11-01

    The treatment options and planning techniques used by the town of Castle Rock (Colorado) for a new water treatment facility are described. Castle Rock officials assessed the available treatment options for dissolved iron and manganese removal and selected potassium permanganate as the primary oxidant to be followed by manganese greensand. A backup prechlorination system for oxidation was also installed. In addition, to prevent excess headloss buildup in the manganese greensand filter media, an anthracite carbon cap was used as the top filter medium for precipitate removal. It is recommended that a treatability study be performed to determine individual design criteria to allow for specific site conditions. The town also assessed the capital and operation and maintenance costs for both treatment at individual well fields and a centralized location for treatment of a cluster of well fields. The results indicate that it is more economical to provide centralized water treatment even though there are capital costs associated with piping raw water from the individual well fields to the central facility. 3 refs.

  12. Mercury distribution characteristics in primary manganese smelting plants.

    Science.gov (United States)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-08-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1-99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. Copyright © 2017. Published by Elsevier Ltd.

  13. HDM model magnet mechanical behavior with high manganese steel collars

    International Nuclear Information System (INIS)

    Snyder, J.R.

    1994-01-01

    Westinghouse Electric Corporation (WEC) is presently under contract to the SSCL to design, develop, fabricate, and deliver superconducting dipole magnets for the High Energy Booster (HEB). As a first step toward these objectives SSCL supplied a design for short model magnets of 1.8 m in length (DSB). This design was used as a developmental tool for all phases of engineering and fabrication. Mechanical analysis of the HDM (High Energy Booster Dipole Magnets) model magnet design as specified by SSCL was performed with the following objectives: (1) to develop a thorough understanding of the design; (2) to review and verify through analytical and numerical analyses the SSCL model magnet design; (3) to identify any deficiencies that would violate design parameters specified in the HDM Design Requirements Document. A detailed analysis of the model magnet mechanical behavior was pursued by constructing a quarter section finite element model and solving with the ANSYS finite element code. Collar materials of Nitronic-40 and High-Manganese steel were both considered for the HEB model magnet program with the High-Manganese being the final selection. The primary mechanical difference in the two materials is the much lower thermal contraction of the High-Manganese steel. With this material the collars will contract less than the enclosing yoke producing an increased collar yoke interference during cooldown

  14. Laser microstructuring and annealing processes for lithium manganese oxide cathodes

    International Nuclear Information System (INIS)

    Proell, J.; Kohler, R.; Torge, M.; Ulrich, S.; Ziebert, C.; Bruns, M.; Seifert, H.J.; Pfleging, W.

    2011-01-01

    It is expected that cathodes for lithium-ion batteries (LIB) composed out of nano-composite materials lead to an increase in power density of the LIB due to large electrochemically active surface areas but cathodes made of lithium manganese oxides (Li-Mn-O) suffer from structural instabilities due to their sensitivity to the average manganese oxidation state. Therefore, thin films in the Li-Mn-O system were synthesized by non-reactive radiofrequency magnetron sputtering of a spinel lithium manganese oxide target. For the enhancement of the power density and cycle stability, large area direct laser patterning using UV-laser radiation with a wavelength of 248 nm was performed. Subsequent laser annealing processes were investigated in a second step in order to set up a spinel-like phase using 940 nm laser radiation at a temperature of 680 deg. C. The interaction processes between UV-laser radiation and the material was investigated using laser ablation inductively coupled plasma mass spectroscopy. The changes in phase, structure and grain shape of the thin films due to the annealing process were recorded using Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The structured cathodes were cycled using standard electrolyte and a metallic lithium anode. Different surface structures were investigated and a significant increase in cycling stability was found. Surface chemistry of an as-deposited as well as an electrochemically cycled thin film was investigated via X-ray photoelectron spectroscopy.

  15. Diode laser heat treatment of lithium manganese oxide films

    International Nuclear Information System (INIS)

    Pröll, J.; Kohler, R.; Mangang, A.; Ulrich, S.; Bruns, M.; Seifert, H.J.; Pfleging, W.

    2012-01-01

    The crystallization of lithium manganese oxide thin films prepared by radio frequency magnetron sputtering on stainless steel substrates under 10 Pa argon pressure is demonstrated by a laser annealing technique. Laser annealing processes were developed as a function of annealing time and temperature with the objective to form an electrochemically active lithium manganese oxide cathode. It is demonstrated, that laser annealing with 940 nm diode laser radiation and an annealing time of 2000 s at 600 °C delivers appropriate parameters for formation of a crystalline spinel-like phase. Characteristic features of this phase could be detected via Raman spectroscopy, showing the characteristic main Raman band at 627 cm -1 . Within cyclic voltammetric measurements, the two characteristic redox pairs for spinel lithium manganese oxide in the 4 V region could be detected, indicating that the film was well-crystallized and de-/intercalation processes were reversible. Raman post-analysis of a cycled cathode showed that the spinel-like structure was preserved within the cycling process but mechanical degradation effects such as film cracking were observed via scanning electron microscopy. Typical features for the formation of an additional surface reaction layer could be detected using X-ray photoelectron spectroscopy.

  16. Elevated airborne manganese and low executive function in school-aged children in Brazil.

    Science.gov (United States)

    Carvalho, Chrissie F; Menezes-Filho, José A; de Matos, Vitor P; Bessa, Jonatas Reis; Coelho-Santos, Juliana; Viana, Gustavo F S; Argollo, Nayara; Abreu, Neander

    2014-12-01

    Exposure to airborne manganese (Mn) has been associated with neurotoxic effects, including motor and cognitive deficits. The main deficits related to excessive exposure to Mn are predominantly the dysfunction of fronto-striatal and dopaminergic circuits observed in animal experimental studies, which are involved in attention, working memory and motor function. The present study aims to assess the association between elevated Mn exposure and performance on executive function and attention neuropsychological tests in children living in two communities near a ferro-manganese alloy plant. Seventy children aged between 7 and 12 years with no history of neurologic disease and an estimated IQ >68 (Vocabulary and Block Design subtests) that had lived near the iron-Mn production alloy plant for at least 1.5 years were included. Participants were assessed for cognitive functioning with neuropsychological measures for sustained attention (Test of Visual Attention - TAVIS-3R), cognitive flexibility (WCST), and verbal and visual working memory (WISC-III Digit Span subtest and Corsi Block). Manganese hair (MnH) levels were used as a biomarker of exposure. Mean scores among study participants were lower than general population norms/averages for block design, digit span, reaction time and commission errors. The median MnH level was 11.48 (range 0.52-55.74) μg/g, and no difference between sexes was observed. Spearman's correlation analysis showed a significant inverse correlation between MnH levels and estimated IQ (rho=-0.448, p=0.0001), Vocabulary (rho=-0.272, p=0.02), Block Design (rho=-0.485, p=0.00002) and Digit Span (rho=-0.410, p=0.0004). Multiple regression analyses detected inverse associations between log MnH and scores on estimated IQ (β=-9.67; 95%CI=-16.97 to -2.37), Block Design (β=-2.50; 95%CI=-3.91 to -1.10) and Digit Span Total (β=-2.59; 95%CI=-4.13 to -1.05) standardized scores and the number of correct answers in forward and backward Digit Span methods, after

  17. Microstructure and spectroscopic investigations of calcium zinc bismuth phosphate glass ceramics doped with manganese ions

    Science.gov (United States)

    Suneel Kumar, A.; Sambasiva Rao, M. V.; Chinna Ram, G.; Krishna Rao, D.

    2018-01-01

    Multi-component 10CaF2-20ZnO-(15 - x)Bi2O3-55P2O5:xMnO (0 ≤ x ≤ 2.5) glass ceramics were synthesised by melt quenching technique and heat treatment. The prepared glass ceramics were characterised by XRD, DTA, EDS and SEM. Spectroscopic studies such as optical absorption, EPR, FTIR and Raman were also carried out on these glass ceramics. The XRD and SEM studies have indicated that ceramic samples contain well defined and randomly distributed grains of different crystalline phases. The observed increase of enthalpy from DTA patterns up to 1 mol% of MnO indicates that the crystallisation starts initially from the surface of the material then gradually it is extended to the volume of the material and this influence is meagre at higher concentrations of MnO. The absorption spectra of manganese doped glass ceramics have exhibited two types of conventional bands; one due to Mn2+ ions and other due to Mn3+ ions. The EPR spectra of MnO doped glass ceramics showed a resonance signal around g2 = 2.023 with a six line hyperfine structure and another signal at about g1 = 4.314. The relative intensity and half-width of these two signals are observed to increase with the increase in the concentration of manganese ions up to 1 mol% beyond this concentration it is found to decrease. Such observation indicates the conversion of part of Mn2+ ions into Mn3+ ions in the glass ceramic matrix. The observed increase in the intensity of symmetrical structural units at the expense of asymmetrical structural units from the FTIR and Raman spectra at higher concentration of MnO indicating that Mn2+ ions occupy the network forming positions in the glass ceramic structure.

  18. Bacterial Disproportionation of Elemental Sulfur Coupled to Chemical Reduction of Iron or Manganese

    Science.gov (United States)

    Thamdrup, Bo; Finster, Kai; Hansen, Jens Würgler; Bak, Friedhelm

    1993-01-01

    A new chemolithotrophic bacterial metabolism was discovered in anaerobic marine enrichment cultures. Cultures in defined medium with elemental sulfur (S0) and amorphous ferric hydroxide (FeOOH) as sole substrates showed intense formation of sulfate. Furthermore, precipitation of ferrous sulfide and pyrite was observed. The transformations were accompanied by growth of slightly curved, rod-shaped bacteria. The quantification of the products revealed that S0 was microbially disproportionated to sulfate and sulfide, as follows: 4S0 + 4H2O → SO42- + 3H2S + 2H+. Subsequent chemical reactions between the formed sulfide and the added FeOOH led to the observed precipitation of iron sulfides. Sulfate and iron sulfides were also produced when FeOOH was replaced by FeCO3. Further enrichment with manganese oxide, MnO2, instead of FeOOH yielded stable cultures which formed sulfate during concomitant reduction of MnO2 to Mn2+. Growth of small rod-shaped bacteria was observed. When incubated without MnO2, the culture did not grow but produced small amounts of SO42- and H2S at a ratio of 1:3, indicating again a disproportionation of S0. The observed microbial disproportionation of S0 only proceeds significantly in the presence of sulfide-scavenging agents such as iron and manganese compounds. The population density of bacteria capable of S0 disproportionation in the presence of FeOOH or MnO2 was high, > 104 cm-3 in coastal sediments. The metabolism offers an explanation for recent observations of anaerobic sulfide oxidation to sulfate in anoxic sediments. PMID:16348835

  19. Subchronic, Low-Level Intraperitoneal Injections of Manganese (IV) Oxide and Manganese (II) Chloride Affect Rat Brain Neurochemistry

    DEFF Research Database (Denmark)

    Nielsen, Brian S.; Larsen, Erik Huusfeldt; Ladefoged, Ole

    2017-01-01

    Manganese (Mn) is neurotoxic and can induce manganism, a Parkinson-like disease categorized as being a serious central nervous system irreversible neurodegenerative disease. An increased risk of developing symptoms of Parkinson disease has been linked to work-related exposure, for example......Cl2)/kg bw/day for 7 d/wk for 8 or 12 weeks. This dosing regimen adds relevant new knowledge about Mn neurotoxicity as a consequence of low-dose subchronic Mn dosing. Manganese concentrations increased in the striatum, the rest of the brain, and in plasma, and regional brain neurotransmitter...... with MnCl2. Plasma prolactin concentration was not significantly affected due to a potentially reduced dopaminergic inhibition of the prolactin release from the anterior hypophysis. No effects on the striatal α-synuclein and synaptophysin protein levels were detected....

  20. Study and determination of the ratio atoms between hydrogen and manganese in the manganese sulphate bath: procedure and calculation

    International Nuclear Information System (INIS)

    Castro, Leonardo C. de; Pereira, Walsan W.; Fonseca, Evaldo S.; Leite, Sandro P.

    2007-01-01

    The Brazilian Neutron Laboratory (LN) is part of the National Laboratory of Ionising Radiation of Metrology (LNMRI/IRD). It operates a system for absolute standardization for the measurement of the neutrons sources fluence. The Manganese Sulphate Bath (MSB) is part of this measurement system and was donated by the Bureau International de Poids et Measures (BIPM) in 1996. Since then at LN has become a fulfilled inquiry and measurements of fluence rate of a neutrons source Q. LN has carried through activities for the maintenance and dissemination of the reference values for this primary standard. Currently LN advances in two work lines: One of them is the study of the bath sensibility of the detection system (e), and the other is the study of f parameter, that measures the fraction of captured neutrons by 55 Mn. In the present work, we dedicate special attention to the measurement of the neutron fraction that depends on the amount of ratio atoms between hydrogen and manganese. A revision of the procedures and the experience involved with the measurement system gave chance to evaluate points for a metrology refinement leading to lower uncertainties and greater reliability degree values. To obtain the cited refinement, the following stages had been fulfilled: Firstly, the development of a tool for confection of standardized crucibles. Secondly, the characterization of the muffle used in the work through the survey of heating slopes. And finally, the study of the volatility with the temperature of manganese sulphate (MnSO4 + H2O) through a thermo-gravimetric analysis in the own muffle conditions used in the work. It was observed that the steady temperature of operation in the quantification of the Manganese in the solution meets above of 350 deg C and this caused a significant improvement over the measurement proceeding. This work demonstrates that the improvements in the proceeding for the determination of the NH/NMn ratio leads to the one of the goals longed for this

  1. Effects of manganese and manganese-nitrogen applications on growth and nutrition of Douglas-fir seedlings.

    Science.gov (United States)

    M. A. Radwan; John S. Shumway; Dean S. DeBell

    1979-01-01

    Effects of manganese (Mn) on Douglas-fir grown in soil, with and without urea, and in nutrient solution were investigated. In addition, Mn sorption by forest soils was evaluated. Results show that Douglas-fir does not respond to added Mn and is quite tolerant to high Mn levels. Moreover, Mn sorption by soils is high. It is doubtful that Mn toxicity is of practical...

  2. Effects of manganese exposure on visuoperception and visual memory in schoolchildren.

    Science.gov (United States)

    Hernández-Bonilla, D; Escamilla-Núñez, C; Mergler, D; Rodríguez-Dozal, S; Cortez-Lugo, M; Montes, S; Tristán-López, L A; Catalán-Vázquez, M; Schilmann, A; Riojas-Rodriguez, Horacio

    2016-12-01

    Manganese (Mn) is an essential metal involved in multiple physiological functions. Environmental exposure to airborne Mn is associated with neurocognitive deficits in humans. Children, whose nervous system is in development, are particularly susceptible to Mn neurotoxicity. The objective of this study was to assess the association between Mn environmental exposure, and effects on visuoperception and visual memory in schoolchildren. We assessed schoolchildren between 7 and 11 years old, with similar socioeconomic status, from the mining district of Molango (n=148) and Agua Blanca (n=119, non-mining area) in Hidalgo state, Mexico. The Rey-Osterrieth Complex Figure (ROCF) test was used to assess visuoperception and short-term visual memory. Hair manganese (MnH) concentrations were determined. Linear regression models were constructed to estimate the associations between MnH and ROCF scores, adjusted for potential confounders. The geometric mean MnH was nine times higher in schoolchildren from the Mn mining area (5.25μg/g) than in schoolchildren from the non-mining area (0.55μg/g). For the ROCF Copy trial, MnH was significantly associated with an increase in distortion errors (tangency, closure), angle errors, overtracing (partial overtracing). In the Immediate Recall trial, MnH was significantly associated with increased overtracing (partial overtracing) and omissions, and negatively associated with the number of perceptual drawn units, total score and percentage immediate recall. MnH is associated with alterations in visuoperception and short-term visual memory in schoolchildren exposed to airborne Mn. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Manganese kinetics in the shore crab Carcinus maenas exposed via food and water

    International Nuclear Information System (INIS)

    Bjerregaard, P.; Hastrup, M.

    1999-01-01

    Oxygen depletion in marine water has been an increasing problem in many coastal areas due to eutrophication. Under hypoxic and anoxic conditions in bottom waters, the flux of manganese out of the sediment increases and substantial concentrations of dissolved manganese in the water column can be reached. Manganese liberated as Mn ++ from the sediment during hypoxic conditions is re-oxidised fairly slowly (in order of weeks) after reintroduction of oxygen to the water. Therefore, benthic organisms may encounter concurrent exposure to increased manganese concentrations and hypoxic condition

  4. Kinetics of manganese in MAG/MIG welding with a 18/8/6 wire

    OpenAIRE

    Tušek, Janez

    2001-01-01

    The paper deals with a study of MAG/MIG welding of low-alloy ferritic steel and highalloy austenitic steel with a 18/8/6 wire. Manganese burn-off from the wire in welding a single-V butt weld was studied. It was found that manganese burns off in the arc during melting of a droplet at the wire end, and from the weld pool during weld formation. The range of manganese burn-off depends mainly on the type of shielding gas used and the arc length, i.e., from the arc voltage. The manganese burn-off ...

  5. Influence of oxalic acid on the dissolution kinetics of manganese oxide

    Science.gov (United States)

    Godunov, E. B.; Artamonova, I. V.; Gorichev, I. G.; Lainer, Yu. A.

    2012-11-01

    The kinetics and electrochemical processes of the dissolution of manganese oxides with various oxidation states in sulfuric acid solutions containing oxalate ion additives is studied under variable conditions (concentration, pH, temperature). The parameters favoring a higher degree of the dissolution of manganese oxides in acidic media are determined. The optimal conditions are found for the dissolution of manganese oxides in acidic media in the presence of oxalate ions. The mechanism proposed for the dissolution of manganese oxides in sulfuric acid solutions containing oxalic acid is based on the results of kinetic and electrochemical studies. The steps of the dissolution mechanism are discussed.

  6. Lithium containing manganese dioxide (composite dimensional manganese oxide-CDMO) as a cathod active material for lithium secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Nobuhiro; Noma, Toshiyuki; Teraji, Kazuo; Nakane, Ikuo; Yamamoto, Yuji; Saito, Toshihiko (Sanyo Electric Co., Ltd., Osaka, Japan)

    1989-06-05

    Manganese dioxide containing lithium ions in a solid matrix was investigated in the lithium nonaqueous cell. Li/sub x/MnO/sub 2+{delta}/ material prepared, with the thermal treatment, by the solid state reaction of manganese dioxide and lithium hydroxide, 7 to 3 in molar ratio, at the temperature of 375{sup 0}C in air for 20 hours, exhibited the rechargeability in the lithium nonaqueous cell. A discharging and changing cycle test, 0.14 or 0.26e/Mn in each of both the discharge and charge, was also made, with the use of a flat type cell, to demonstrate it in performance. Synthetic Li/sub x/MnO/sub 2+{delta}/ was discussed, in advantageous use for the secondary lithium cell, based on the discharging and charging characteristics. As a conclusion of the foregoing, composite dimensional manganese oxide is expected to be good as active material of positive electrode for the secondary lithium cell use. 11 refs., 11 figs., 3 tabs.

  7. Defining asthma in genetic studies

    NARCIS (Netherlands)

    Koppelman, GH; Postma, DS; Meijer, G.

    1999-01-01

    Genetic studies have been hampered by the lack of a gold standard to diagnose asthma. The complex nature of asthma makes it more difficult to identify asthma genes. Therefore, approaches to define phenotypes, which have been successful in other genetically complex diseases, may be applied to define

  8. Biogenic manganese oxide nanoparticle formation by a multimeric multicopper oxidase Mnx.

    Science.gov (United States)

    Romano, Christine A; Zhou, Mowei; Song, Yang; Wysocki, Vicki H; Dohnalkova, Alice C; Kovarik, Libor; Paša-Tolić, Ljiljana; Tebo, Bradley M

    2017-09-29

    Bacteria that produce Mn oxides are extraordinarily skilled engineers of nanomaterials that contribute significantly to global biogeochemical cycles. Their enzyme-based reaction mechanisms may be genetically tailored for environmental remediation applications or bioenergy production. However, significant challenges exist for structural characterization of the enzymes responsible for biomineralization. The active Mn oxidase in Bacillus sp. PL-12, Mnx, is a complex composed of a multicopper oxidase (MCO), MnxG, and two accessory proteins, MnxE and MnxF. MnxG shares sequence similarity with other, structurally characterized MCOs. MnxE and MnxF have no similarity to any characterized proteins. The ~200 kDa complex has been recalcitrant to crystallization, so its structure is unknown. Here, we show that native mass spectrometry defines the subunit topology and copper binding of Mnx, while high-resolution electron microscopy visualizes the protein and nascent Mn oxide minerals. These data provide critical structural information for understanding Mn biomineralization by such unexplored enzymes.Significant challenges exist for structural characterization of enzymes responsible for biomineralization. Here the authors show that native mass spectrometry and high resolution electron microscopy can define the subunit topology and copper binding of a manganese oxidizing complex, and describe early stage formation of its mineral products.

  9. Heavy metals and manganese oxides in the genesee watershed, New York state: effects of geology and land use

    Science.gov (United States)

    Whitney, P.R.

    1981-01-01

    Manganese oxide coatings on gravels from 255 sites on tributary streams in the Genesee River Watershed were analyzed for Mn, Fe, Zn, Cd, Co, Ni, Pb, and Cu. The results were compared with data on bedrock geology, surficial geology and land use, using factor analysis and stepwise multiple regression. All metals except Pb show strong positive correlation with Mn. This association results from the well-known tendency of Mn oxide precipitates to adsorb and incorporate dissolved trace metals. Pb may be present in a separate phase on the gravel surfaces; alternatively Pb abundance may be so strongly influenced by environmental factors that the effect of varying abundance of the carrier phase becomes relatively unimportant. When the effects of varying Mn abundance are allowed for, Pb and to a lesser extent Zn and Cu abundances are seen to be related to commercial, industrial and residential land use. In addition to this pollution effect, all the trace metals, Cd and Ni most strongly, tend to be more abundant in oxide coatings from streams in the forested uplands in the southern part of the area. This probably reflects increased geochemical mobility of the metals in the more acid soils and groundwater of the southern region. A strong Zn anomaly is present in streams draining areas underlain by the Lockport Formation. Oxide coatings in these streams contain up to 5% Zn, originating from disseminated sphalerite in the Lockport and secondary Zn concentrations in the overlying muck soils. The same group of metals, plus calcium and loss on ignition, were determined in the silt and clay (minus 230 mesh) fraction of stream sediments from 129 of the same sites, using a hot nitric acid leach. The amounts of manganese in the sediments are low (average 1020 ppm) and manganese oxides are, at most, of relatively minor significance in the trace-metal geochemistry of these sediments. The bulk of the trace metals in sediment appears to be associated with iron oxides, clays and organic

  10. Theoretical approaches to elections defining

    OpenAIRE

    Natalya V. Lebedeva

    2011-01-01

    Theoretical approaches to elections defining develop the nature, essence and content of elections, help to determine their place and a role as one of the major national law institutions in democratic system.

  11. Theoretical approaches to elections defining

    Directory of Open Access Journals (Sweden)

    Natalya V. Lebedeva

    2011-01-01

    Full Text Available Theoretical approaches to elections defining develop the nature, essence and content of elections, help to determine their place and a role as one of the major national law institutions in democratic system.

  12. Defining Modules, Modularity and Modularization

    DEFF Research Database (Denmark)

    Miller, Thomas Dedenroth; Pedersen, Per Erik Elgård

    The paper describes the evolution of the concept of modularity in a historical perspective. The main reasons for modularity are: create variety, utilize similarities, and reduce complexity. The paper defines the terms: Module, modularity, and modularization.......The paper describes the evolution of the concept of modularity in a historical perspective. The main reasons for modularity are: create variety, utilize similarities, and reduce complexity. The paper defines the terms: Module, modularity, and modularization....

  13. Manganese oxalate nanorods as ballistic modifier for composite solid propellants

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Supriya [Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, U.P. (India); Chawla, Mohit [School of Basic Sciences, Indian Institute of Technology Mandi, Mandi 175005, H.P. (India); Siril, Prem Felix, E-mail: prem@iitmandi.ac.in [School of Basic Sciences, Indian Institute of Technology Mandi, Mandi 175005, H.P. (India); Singh, Gurdip [Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, U.P. (India)

    2014-12-10

    Highlights: • Manganese oxalate nanorods were prepared using mild thermal precipitation and aging. • The nanorods were found to be efficient ballistic modifier for solid propellants. • The nanorods sensitized the thermolysis of ammonium perchlorate. • Controlled thermal decomposition of nanorods yielded manganese oxide nanoparticles. • MnO nanoparticles formed insitu in the condensed phase enhance the burning rates. - Abstract: Rod-shaped nanostructures of manganese oxalate (MnC{sub 2}O{sub 4}) were synthesized via mild thermal precipitation and aging process. Chemical composition of the MnC{sub 2}O{sub 4} nanorods was confirmed using Fourier transform infra-red (FTIR) spectroscopy and energy dispersive X-ray spectroscopy (EDS). X-ray diffraction (XRD) and selected area electron diffraction (SAED) studies revealed the crystal structure. Field emission scanning electron microscopy (FE-SEM) imaging and high resolution transmission electron microscopy (HR-TEM) were employed to study the structural features of the nanorods. The MnC{sub 2}O{sub 4} nanorods were found to be efficient ballistic modifier for the burning rate enhancement of composite solid propellants (CSPs). Thermal analysis using TGA-DSC showed that MnC{sub 2}O{sub 4} nanorods sensitized the thermal decomposition of ammonium perchlorate (AP) and the CSPs. Controlled thermal decomposition of the MnC{sub 2}O{sub 4} nanorods resulted in the formation of managanese oxide nanoparticles with mesoporosity. A plausible mechanism for the burning rate enhancement using MnC{sub 2}O{sub 4} nanorods was proposed.

  14. Nuclear orientation studies of manganese in copper Kondo system

    International Nuclear Information System (INIS)

    Bakalyar, D.

    1977-08-01

    The internal field seen by the 54 Mn nuclei in a dilute (about 1 part per billion) manganese in copper Kondo system was measured using nuclear orientation. The measurements were made at temperatures on the order of 4 mK in applied fields of 5 kG to 40 kG. Temperatures were measured using a 60 Co in nickel nuclear orientation thermometer and were achieved by adiabatically demagnetizing an ingot of the hyperfine enhanced nuclear coolant PrCu 6 from temperatures of about 30 mK (the mixing chamber temperature of a dilution refrigerator). The data was temperature independent but there was evidence of iteractions between the manganese atoms at manganese concentrations of 1 / 2 part per million. The data was interpreted by assuming that the internal field consisted of the hyperfine field minus the applied field (i.e. the hyperfine field and applied field were aligned in opposite directions). The hyperfine field versus applied field data was compared to three approximate solutions to the Kondo Hamiltonian. Two of the solutions, one by Luther and Emery and the other by Goetze and Schlottmann, fit the data very well. The third solution, that proposed by Ishii, does not fit the data. Fitted to the data, the Luther-Emery solution predicts a saturation value of the hyperfine field of 303 kG whereas the Goetze-Schlottmann solution predicts a saturation value of 297 kG. The hyperfine field is only beginning to reach its saturation value with applied fields of 40 kG

  15. Tensile behavior of irradiated manganese-stabilized stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    Tensile tests were conducted on seven experimental, high-manganese austenitic stainless steels after irradiation up to 44 dpa in the FFTF. An Fe-20Mn-12Cr-0.25C base composition was used, to which various combinations of Ti, W, V, B, and P were added to improve strength. Nominal amounts added were 0.1% Ti, 1% W, 0.1% V, 0.005% B, and 0.03% P. Irradiation was carried out at 420, 520, and 600{degrees}C on the steels in the solution-annealed and 20% cold-worked conditions. Tensile tests were conducted at the irradiation temperature. Results were compared with type 316 SS. Neutron irradiation hardened all of the solution-annealed steels at 420, 520, and 600{degrees}C, as measured by the increase in yield stress and ultimate tensile strength. The steel to which all five elements were added to the base composition showed the least amount of hardening. It also showed a smaller loss of ductility (uniform and total elongation) than the other steels. The total and uniform elongations of this steel after irradiation at 420{degrees}C was over four times that of the other manganese-stabilized steels and 316 SS. There was much less difference in strength and ductility at the two higher irradiation temperatures, where there was considerably less hardening, and thus, less loss of ductility. In the cold-worked condition, hardening occured only after irradiation at 420{degrees}C, and there was much less difference in the properties of the steels after irradiation. At the 420{degrees}C irradiation temperature, most of the manganese-stabilized steels maintained more ductility than the 316 SS. After irradiation at 420{degrees}C, the temperature of maximum hardening, the steel to which all five of the elements were added had the best uniform elongation.

  16. The Escherichia coli small protein MntS and exporter MntP optimize the intracellular concentration of manganese.

    Directory of Open Access Journals (Sweden)

    Julia E Martin

    2015-03-01

    Full Text Available Escherichia coli does not routinely import manganese, but it will do so when iron is unavailable, so that manganese can substitute for iron as an enzyme cofactor. When intracellular manganese levels are low, the cell induces the MntH manganese importer plus MntS, a small protein of unknown function; when manganese levels are high, the cell induces the MntP manganese exporter and reduces expression of MntH and MntS. The role of MntS has not been clear. Previous work showed that forced MntS synthesis under manganese-rich conditions caused bacteriostasis. Here we find that when manganese is scarce, MntS helps manganese to activate a variety of enzymes. Its overproduction under manganese-rich conditions caused manganese to accumulate to very high levels inside the cell; simultaneously, iron levels dropped precipitously, apparently because manganese-bound Fur blocked the production of iron importers. Under these conditions, heme synthesis stopped, ultimately depleting cytochrome oxidase activity and causing the failure of aerobic metabolism. Protoporphyrin IX accumulated, indicating that the combination of excess manganese and iron deficiency had stalled ferrochelatase. The same chain of events occurred when mutants lacking MntP, the manganese exporter, were exposed to manganese. Genetic analysis suggested the possibility that MntS exerts this effect by inhibiting MntP. We discuss a model wherein during transitions between low- and high-manganese environments E. coli uses MntP to compensate for MntH overactivity, and MntS to compensate for MntP overactivity.

  17. Growth rate and chemical composition of a manganese nodule from the EEZ of Seychelles

    Digital Repository Service at National Institute of Oceanography (India)

    Banakar, V.K.; Borole, D.V.

    mhe ferro-manganese nodule collected in EEZ of Seychelles yields a growth rate of 1.5 mm/10 6Y 230Th (ex)/ and 230Th (ex)/ 232Th activity ratio methods indicating very slow growth of ferro-manganese nodules. The Mn/Fe and U/Th ratios suggest...

  18. Neutron-activation analysis for investigation of biochemical manganese in soils cotton soweol zone of Uzbekistan

    International Nuclear Information System (INIS)

    Zhumamuratov, A.; Tillaev, T.; Khatamov, Sh.; Suvanov, M.; Osinskaya, N.S.; Rakhmanova, T.P.

    2004-01-01

    Full text: For many years we neutron activation analysis of soils sampled from different areas of landscape-geochemical regions of Uzbekistan including zone of extreme ecological catastrophe of Aral. Content of manganese and some other elements in the 'soil-cotton' system was investigated. Neutron-activation method of manganese determining with productivity up to 400 samples on shift with detection limit of 1,1 10 -5 % and discrepancies not more than 10%. Was developed extremely uniform distribution of manganese in cotton sowed soils of the Republic (340-1800mg/kg) is determined. Practically all soils of cotton-sowed zone of Republic are with lack of manganese. Distribution of manganese on soil profile of separate organs of cotton (leaves seeds etc.) was studied. Correlation between gross concentration of manganese and its active part extracted by distilled water on the basis of quantity analysis was found. Successive comparison of gross content of manganese in the soil with crop capacity of cotton in different zones of Republic made it possible to find interconnection between these quantities, which proves necessity of using micro-additions of manganese in the soils where its low concentration is detected

  19. 76 FR 47996 - Cobalt Lithium Manganese Nickel Oxide; Significant New Use Rule

    Science.gov (United States)

    2011-08-08

    ... Safety and Health Administration (OSHA) Permissible Exposure Level (PEL) of 0.1 mg/m\\3\\ for nickel. The... 2070-AB27 Cobalt Lithium Manganese Nickel Oxide; Significant New Use Rule AGENCY: Environmental... lithium manganese nickel oxide (CAS No. 182442-95-1), which was the subject of premanufacture notice (PMN...

  20. Arsenic enrichment in estuarine sediments-impact of iron and manganese mining

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, M.; Joseph, T.; Balachandran, K.K.; Nair, K.K.C.; Paimpillii, J.S.

    River Mandovi and Zuari, Goa (west coast of India) are flowing through iron and manganese mining areas and are heavily used for iron and manganese ore transport. This region generates 25-30 million tons of mining rejects per year. The iron ore...

  1. Dissolution of manganese and cobalt and their deposition on Type 304 stainless steel in liquid sodium

    International Nuclear Information System (INIS)

    Yokota, Norikatsu; Shimoyashiki, Shigehiro

    1989-01-01

    Dissolution of manganese and cobalt and their deposition on Type 304 stainless steel in liquid sodium at 833 K for 3.6 x 10 3 ks were examined using a liquid sodium pot. Manganese was easily dissolved in sodium from the iron-manganese alloy specimen and deposited on the steel to form two kind of deposition particles, α-phase (body-centered cubic) composed of iron and γ-phase (face-centered cubic) composed of iron and manganese, respectively. Cobalt which was less easily dissolved than manganese also deposited on the Type 304 stainless steel, giving an iron-cobalt alloy. These three deposition particles corresponded to the precipitation lines of iron-manganese and iron-cobalt phase diagrams at 833 K, respectively. Therefore, the deposition process of manganese or cobalt in sodium was explained as a precipitation process of iron-manganese or iron-cobalt in the solid region of the binary phase diagram. A sodium chromite (NaCrO 2 ) layer was formed on the steel surface. (author)

  2. Early diagenesis of manganese, iron and phosphorus in European continental margin sediments

    NARCIS (Netherlands)

    Zee, C. van der

    2002-01-01

    This thesis describes the results of a project that was carried out as a part of the Sedimentary Manganese and Iron cycLEs (SMILE) research program funded by the Netherlands Organisation of Scientific Research (NWO/ALW). SMILE aimed at studying the biogeochemistry of iron and manganese cycles in

  3. Early diagenesis of Manganese, Iron and Phosphorus in European continental margin sediments

    NARCIS (Netherlands)

    van der Zee, C.

    2002-01-01

    This thesis describes the results of a project that was carried out as a part of the Sedimentary Manganese and Iron cycLEs (SMILE) research program funded by the Netherlands Organisation of Scientific Research (NWO/ALW). SMILE aimed at studying the biogeochemistry of iron and manganese cycles in

  4. Field-induced resistance switching at metal/perovskite manganese oxide interface

    International Nuclear Information System (INIS)

    Ohkubo, I.; Tsubouchi, K.; Harada, T.; Kumigashira, H.; Itaka, K.; Matsumoto, Y.; Ohnishi, T.; Lippmaa, M.; Koinuma, H.; Oshima, M.

    2008-01-01

    Planar type metal/insulator/metal structures composed of an epitaxial perovskite manganese oxide layer and various metal electrodes were prepared for electric-field-induced resistance switching. Only the electrode pairs including Al show good resistance switching and the switching ratio reaches its maximum of 1000. This resistance switching occurs around the interface between Al electrodes and epitaxial perovskite manganese oxide thin films

  5. Manganese toxicity effects on nodulation and nitrogen fixation of beans (Phaseolus vulgaris L. ), in acid soils

    Energy Technology Data Exchange (ETDEWEB)

    Doebereiner, J

    1966-02-01

    Three greenhouse experiments were conducted to study manganese toxicity effects on the nitrogen fixing symbiosis of beans (Phaseolus vulgaris). Addition of 40 ppm of manganese to two acid soils affected nodulation and nitrogen fixation. Dependent on the Rhizobion strain either nodule numbers or efficiency in nitrogen fixation were reduced; the efficiency of one Rhizobium-host combination was more affected than another. Under less severe conditions of manganese toxicity, reduction of nodule numbers or of efficiency in nitrogen fixation could be compensated by an increase of nodule size. In the absence of manganese toxicity nodulation and nitrogen fixation of beans were abundant in a soil with pH 4.4. Naturally occurring manganese toxicity in a gray hydromorphic soil was eliminated by liming. The total nitrogen content of bean plants which were dependent on symbiotic nitrogen fixation decreased linearly with the logarithm of the manganese concentration in the plants. This did not happen when the plants were grown with mineral nitrogen. The role of manganese toxicity in the well known sensitivity to acid soil conditions of certain legumes and the importance of selection of manganese tolerant Rhizobium strains for the inoculation of beans in acid tropical soils, are discussed. 25 references, 1 figure, 6 tables.

  6. Manganese oxide/graphene oxide composites for high-energyaqueous asymmetric electrochemical capacitors

    CSIR Research Space (South Africa)

    Jafta, CJ

    2013-11-01

    Full Text Available A high-energy aqueous asymmetric electrochemical capacitor was developed using manganese diox-ide ( -MnO2)/graphene oxide (GO) nanocomposites. The nanostructured -MnO2was prepared frommicron-sized commercial electrolytic manganese dioxide (EMD) via...

  7. Rapid manganese removal from mine waters using an aerated packed-bed bioreactor.

    Science.gov (United States)

    Johnson, Karen L; Younger, Paul L

    2005-01-01

    In the UK, the Environmental Quality Standard for manganese has recently been lowered to 30 microg/L (annual average), which is less than the UK Drinking Water Inspectorate's Maximum Permitted Concentration Value (50 microg/L). Current passive treatment systems for manganese removal operate as open-air gravel-bed filters, designed to maximize either influent light and/or dissolved oxygen. This requires large areas of land. A novel enhanced bioremediation treatment system for manganese removal has been developed that consists of a passively aerated subsurface gravel bed. The provision of air at depth and the use of catalytic substrates help overcome the slow kinetics usually associated with manganese oxidation. With a residence time of only 8 h and an influent manganese concentration of approximately 20 mg/L, >95% of the manganese was removed. The treatment system also operates successfully at temperatures as low as 4 degrees C and in total darkness. These observations have positive implications for manganese treatment using this technique in both colder climates and where large areas of land are unavailable. Furthermore, as the operation of this passive treatment system continually generates fresh manganese oxyhydroxide, which is a powerful sorbent for most pollutant metals, it potentially has major ancillary benefits as a removal process for other metals, such as zinc.

  8. Iron-responsive olfactory uptake of manganese improves motor function deficits associated with iron deficiency.

    Directory of Open Access Journals (Sweden)

    Jonghan Kim

    Full Text Available Iron-responsive manganese uptake is increased in iron-deficient rats, suggesting that toxicity related to manganese exposure could be modified by iron status. To explore possible interactions, the distribution of intranasally-instilled manganese in control and iron-deficient rat brain was characterized by quantitative image analysis using T1-weighted magnetic resonance imaging (MRI. Manganese accumulation in the brain of iron-deficient rats was doubled after intranasal administration of MnCl(2 for 1- or 3-week. Enhanced manganese level was observed in specific brain regions of iron-deficient rats, including the striatum, hippocampus, and prefrontal cortex. Iron-deficient rats spent reduced time on a standard accelerating rotarod bar before falling and with lower peak speed compared to controls; unexpectedly, these measures of motor function significantly improved in iron-deficient rats intranasally-instilled with MnCl(2. Although tissue dopamine concentrations were similar in the striatum, dopamine transporter (DAT and dopamine receptor D(1 (D1R levels were reduced and dopamine receptor D(2 (D2R levels were increased in manganese-instilled rats, suggesting that manganese-induced changes in post-synaptic dopaminergic signaling contribute to the compensatory effect. Enhanced olfactory manganese uptake during iron deficiency appears to be a programmed "rescue response" with beneficial influence on motor impairment due to low iron status.

  9. MAGNETIC INVESTIGATION OF AN UNUSUAL DISSYMMETRIC BINUCLEAR MANGANESE CARBOXYLATE COMPLEX

    Directory of Open Access Journals (Sweden)

    Ghenadie Novitchi

    2006-06-01

    Full Text Available The magnetic susceptibility (χT of an unusual dissymmetric binuclear manganese corboxylate complex has been measured from 2 to 300K. The magnetic data which have been fitted with help of the Heisenberg Dirac Van Vleck HDVV spin-exchange Hamiltonian H = − J S 1 S 2 , indicate that an antiferromagnetic interaction equal to J = -0.90(1 cm-1 is present. A correlation between J values and Mn-H2O-Mn angles has been tempted.

  10. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    Directory of Open Access Journals (Sweden)

    Napachat Tareelap

    2014-03-01

    Full Text Available Due to the failure of manganese aluminium bronze (MAB propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium in seawater to form calcium carbonate film protecting the propeller from corrosion.

  11. Self-assembled manganese oxide structures through direct oxidation

    KAUST Repository

    Zhao, Chao; Wang, Qingxiao; Yang, Yang; Zhang, Bei; Zhang, Xixiang

    2012-01-01

    The morphology and phase of self-assembled manganese oxides during different stages of thermal oxidation were studied. Very interesting morphological patterns of Mn oxide films were observed. At the initial oxidation stage, the surface was characterized by the formation of ring-shaped patterns. As the oxidation proceeded to the intermediate stage, concentric plates formed to relax the compressive stress. Our experimental results gave a clear picture of the evolution of the structures. We also examined the properties of the structures. © 2012 Elsevier B.V.

  12. Self-assembled manganese oxide structures through direct oxidation

    KAUST Repository

    Zhao, Chao

    2012-12-01

    The morphology and phase of self-assembled manganese oxides during different stages of thermal oxidation were studied. Very interesting morphological patterns of Mn oxide films were observed. At the initial oxidation stage, the surface was characterized by the formation of ring-shaped patterns. As the oxidation proceeded to the intermediate stage, concentric plates formed to relax the compressive stress. Our experimental results gave a clear picture of the evolution of the structures. We also examined the properties of the structures. © 2012 Elsevier B.V.

  13. Multitracer method of diffusion measurement in chromium-manganese steels

    International Nuclear Information System (INIS)

    Dudala, J.; Stegowski, Z.; Gilewicz-Wolter, J.

    2004-01-01

    The paper presents an application of multitracer method to diffusion measurement in Cr-Mn steels. Radioisotope tracers of chromium 51 Cr, manganese 54 Mn and iron 59 Fe were used simultaneously in the diffusion process, Gamma-spectrum measurement and the proper analysis enabled evaluation of concentration distribution for each tracer. As a new tool, artificial neural networks (ANN) method was used for spectrum analysis. The proper solution of the diffusion model was applied to the experimental tracers' distribution data and diffusion coefficients were determined. (author)

  14. Neutron activation analysis of manganese in teeth of Japanese adults

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Emiko [Nihon Univ., Tokyo. School of Dentistry

    1982-01-01

    In an investigation of the manganese (Mn) content of teeth in Japanese adults, neutron activation analysis was carried out of caries-free teeth, carious teeth and unerupted teeth gathered from three different districts of Japan. Regular logarithmic distribution of Mn in the dentin suggested that Mn had not been taken into account as an essential element of the teeth. Results of the study revealed no difference in Mn content among these districts, and between the caries-free teeth and the carious teeth, both in enamel and dentin. The Mn content of the enamel was about two times higher than that of the dentin.

  15. Patients with multiple contact allergies

    DEFF Research Database (Denmark)

    Carlsen, Berit Christina; Andersen, Klaus Ejner; Menné, Torkil

    2008-01-01

    Patients with multiple contact allergies, also referred to as polysensitized, are more frequent than predicted from prevalence of single sensitivities. The understanding of why some people develop multiple contact allergies, and characterization of patients with multiple contact allergies...... of developing multiple contact allergies. Evidence of allergen clusters among polysensitized individuals is also reviewed. The literature supports the idea that patients with multiple contact allergies constitute a special entity within the field of contact allergy. There is no generally accepted definition...... of patients with multiple contact allergies. We suggest that contact allergy to 3 or more allergens are defined as multiple contact allergies....

  16. Defining Plagiarism: A Literature Review

    Directory of Open Access Journals (Sweden)

    Akbar Akbar

    2018-02-01

    Full Text Available Plagiarism has repeatedly occurred in Indonesia, resulting in focusing on such academic misbehavior as a “central issue” in Indonesian higher education. One of the issues of addressing plagiarism in higher education is that there is a confusion of defining plagiarism. It seems that Indonesian academics had different perception when defining plagiarism. This article aims at exploring the issue of plagiarism by helping define plagiarism to address confusion among Indonesian academics. This article applies literature review by firs finding relevant articles after identifying databases for literature searching. After the collection of required articles for review, the articles were synthesized before presenting the findings. This study has explored the definition of plagiarism in the context of higher education. This research found that plagiarism is defined in the relation of criminal acts. The huge numbers of discursive features used position plagiaristic acts as an illegal deed. This study also found that cultural backgrounds and exposure to plagiarism were influential in defining plagiarism.

  17. Role of manganese in the resistance of Micrococcus radiodurans to ionizing radiation

    International Nuclear Information System (INIS)

    Wierowski, J.V.

    1980-01-01

    Micrococcus radiodurans possesses a very high level of intracellular manganese compared to other organisms. This manganese content has previously been shown to participate in the exceptional ulraviolet radiation resistance of M. radiodurans. This study was undertaken to determine the role of manganese in the ionizing radiation resistant of M. radiodurans. The results indicate that manganese is essential for DNA degradation to occur during irradiation. Manganese has also proven essential for the second phase of post-irradiation thymine base damage removal. These factors work together to increase the rate of recovery from radiation damage, which is reflected in a larger Dq, D 37 and exponential portion of the survival curve of high Mn-grown cells

  18. Energetic basis of catalytic activity of layered nanophase calcium manganese oxides for water oxidation.

    Science.gov (United States)

    Birkner, Nancy; Nayeri, Sara; Pashaei, Babak; Najafpour, Mohammad Mahdi; Casey, William H; Navrotsky, Alexandra

    2013-05-28

    Previous measurements show that calcium manganese oxide nanoparticles are better water oxidation catalysts than binary manganese oxides (Mn3O4, Mn2O3, and MnO2). The probable reasons for such enhancement involve a combination of factors: The calcium manganese oxide materials have a layered structure with considerable thermodynamic stability and a high surface area, their low surface energy suggests relatively loose binding of H2O on the internal and external surfaces, and they possess mixed-valent manganese with internal oxidation enthalpy independent of the Mn(3+)/Mn(4+) ratio and much smaller in magnitude than the Mn2O3-MnO2 couple. These factors enhance catalytic ability by providing easy access for solutes and water to active sites and facile electron transfer between manganese in different oxidation states.

  19. Hydrothermal manganese oxide deposits from the Izu-Ogasawara (Bonin)-Mariana Arc and adjacent areas

    Energy Technology Data Exchange (ETDEWEB)

    Usui, A.; Nishimura, A. (Geological Survey of Japan, Tsukuba (Japan))

    1992-04-27

    Modern and fossil hydrothermal manganese oxide deposits were discovered from a number of locations in the Izu-Ogasawara(Bonin)-Mariana Arc and adjacent areas during the Hakurei-Maru cruises from 1984 to 1989. This paper describes the occurrence and characteristics of these manganese deposits and their geological significance. It was found that the mineralogical and chemical composition and microstructure of the deposits are typically different from manganese nodules and crusts of hydrogenetic or diagenetic origin. Hardpans, veinlets, sheets, and irregular mass of the hydrothermal manganese deposits often cover a large area of sea bed, which suggests possible high-temperature hydrothermal sulfide deposits in their vicinity. On the other hand, the manganese minerals sometimes occur as substrate of younger hydrogenetic crusts and as nucleus of hydrogenetic nodules, which can provide a geological history of low-temperature hydrothermal activity on the past island arcs. 45 refs., 19 figs., 3 tabs.

  20. Thermodynamic Interactions Among Carbon, Silicon and Iron in Carbon Saturated Manganese Melts

    International Nuclear Information System (INIS)

    Paek, Min-Kyu; Lee, Won-Kyu; Jin, Jinan; Jang, Jung-Mock; Pak, Jong-Jin

    2012-01-01

    Thermodynamics of carbon in manganese alloy melts is important in manufacturing low carbon ferromanganese and silico-manganese alloys. In order to predict the carbon solubility in liquid Mn-Si-Fe-Csat alloys as a function of melt composition and temperature, thermodynamic interactions among carbon, silicon and iron in carbon saturated liquid manganese should be known. In the present study, the effects of silicon and iron on the carbon solubility in Mn-Si, Mn-Fe and Mn-Si-Fe melts were measured in the temperature range from 1673 to 1773 K. The carbon solubility decreases significantly as silicon and iron contents increase in liquid manganese alloy. The interaction parameters among carbon, silicon and iron in carbon saturated liquid manganese were determined from the carbon solubility data and the Lupis' relation for the interaction coefficient at constant activity.

  1. Preparation and characterization of amorphous manganese sulfide thin films by SILAR method

    International Nuclear Information System (INIS)

    Pathan, H.M.; Kale, S.S.; Lokhande, C.D.; Han, Sung-Hwan; Joo, Oh-Shim

    2007-01-01

    Manganese sulfide thin films were deposited by a simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method using manganese acetate as a manganese and sodium sulfide as sulfide ion sources, respectively. Manganese sulfide films were characterized for their structural, surface morphological and optical properties by means of X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and optical absorption measurement techniques. The as-deposited film on glass substrate was amorphous. The optical band gap of the film was found to be thickness dependent. As thickness increases optical band gap was found to be increase. The water angle contact was found to be 34 o , suggesting hydrophilic nature of manganese sulfide thin films. The presence of Mn and S in thin film was confirmed by energy dispersive X-ray analysis

  2. Removal of iron and manganese from groundwater: a study of using potassium permanganate and sedimentation

    Directory of Open Access Journals (Sweden)

    Elsheikh Mohamed

    2018-01-01

    Full Text Available Experiments are done for different combinations of Fe+2 and Mn+2 concentrations. The obtained results show that Potassium Permanganate (PP gives good results in iron and manganese removal. By using PP dose near to half of the theoretically required one, it can remove up to 100 % and 90 % of iron and manganese, respectively over different tested concentrations at pH=7.0. Increasing rate of filtration influences the Mn+2 removal process obviously. Sedimentation is required when combined concentrations of iron and manganese are greater than 5.0 ppm to reduce filter rapid clogging. Using conventional treatment with adding alum, flocculation, sedimentation and filtration can remove up to 97% and 18% of iron and manganese, respectively. Using PP in addition to alum enhances manganese removal but decreases iron removal. However, using alum with increasing pH to 10 leads to 100 % and 95 % of Fe+2 and Mn+2 removal and increases filter working period.

  3. Chronic organic manganese administration in the rat does not damage dopaminergic nigrostriatal neurons.

    Science.gov (United States)

    Yong, V W; Perry, T L; Godolphin, W J; Jones, K A; Clavier, R M; Ito, M; Foulks, J G

    1986-01-01

    In an attempt to produce an animal model of Parkinson's disease, we injected rats repeatedly with high doses of methylcyclopentadienyl manganese tricarbonyl (MMT), a compound which has been reported to lower striatal dopamine content in mice. Chronic MMT administration for up to 5 months, even though it produced a substantial elevation in brain manganese content during the period of exposure, did not destroy dopaminergic nigrostriatal neurons. This was assessed by measurements of tyrosine hydroxylase activity and contents of dopamine and its metabolites in the striatum, and by histological examination of the substantia nigra. Our results differ from those of others who administered manganese chloride in drinking water to rats. This discrepancy is unlikely to be a consequence of differences in duration of exposure or route of administration. It could be due to our having used an organic rather than an inorganic manganese compound, or to a species difference in vulnerability to organic manganese between rats and mice.

  4. Inverse association of intellectual function with very low blood lead but not with manganese exposure in Italian adolescents

    International Nuclear Information System (INIS)

    Lucchini, Roberto G.; Zoni, Silvia; Guazzetti, Stefano; Bontempi, Elza; Micheletti, Serena; Broberg, Karin; Parrinello, Giovanni; Smith, Donald R.

    2012-01-01

    Background: Pediatric lead (Pb) exposure impacts cognitive function and behavior and co-exposure to manganese (Mn) may enhance neurotoxicity. Objectives: To assess cognitive and behavioral function in adolescents with environmental exposure to Pb and Mn. Methods: In this cross sectional study, cognitive function and behavior were examined in healthy adolescents with environmental exposure to metals. The Wechsler Intelligence Scale for Children (WISC) and the Conners-Wells’ Adolescent Self-Report Scale Long Form (CASS:L) were used to assess cognitive and behavioral function, respectively. ALAD polymorphisms rs1800435 and rs1139488 were measured as potential modifiers. Results: We examined 299 adolescents (49.2% females) aged 11–14 years. Blood lead (BPb) averaged 1.71 μg/dL (median 1.5, range 0.44–10.2), mean Blood Manganese (BMn) was 11.1 μg/dL (median 10.9, range 4.00–24.1). Average total IQ was 106.3 (verbal IQ=102, performance IQ=109.3). According to a multiple regression model considering the effect of other covariates, a reduction of about 2.4 IQ points resulted from a two-fold increase of BPb. The Benchmark Level of BPb associated with a loss of 1 IQ-point (BML01) was 0.19 μg/dL, with a lower 95% confidence limit (BMLL01) of 0.11 μg/dL. A very weak correlation resulted between BPb and the ADHD-like behavior (Kendall's tau rank correlation=0.074, p=0.07). No influence of ALAD genotype was observed on any outcome. Manganese was not associated with cognitive and behavioral outcomes, nor was there any interaction with lead. Conclusions: These findings demonstrate that very low level of lead exposure has a significant negative impact on cognitive function in adolescent children. Being an essential micro-nutrient, manganese may not cause cognitive effects at these low exposure levels.

  5. Inverse association of intellectual function with very low blood lead but not with manganese exposure in Italian adolescents

    Energy Technology Data Exchange (ETDEWEB)

    Lucchini, Roberto G., E-mail: lucchini@med.unibs.it [Department of Preventive Medicine, Mount Sinai School of Medicine, NY (United States); Section of Occupational Medicine, University of Brescia, P.le Spedali Civili 1, 25123 Brescia (Italy); Zoni, Silvia [Section of Occupational Medicine, University of Brescia, P.le Spedali Civili 1, 25123 Brescia (Italy); Guazzetti, Stefano [Public Health Service, Reggio Emilia (Italy); Bontempi, Elza [INSTM and Chemistry for Technologies Laboratory, University of Brescia (Italy); Micheletti, Serena [Cognition Psychology Neuroscience lab., University of Pavia and Unit of Child Neurology and Psychiatry, Civil Hospital of Brescia (Italy); Broberg, Karin [Division of Occupational and Environmental Medicine, Lund University (Sweden); Parrinello, Giovanni [Statistics and Biometry, University of Brescia (Italy); Smith, Donald R. [Microbiology and Environmental Toxicology, University of California at Santa Cruz (United States)

    2012-10-15

    Background: Pediatric lead (Pb) exposure impacts cognitive function and behavior and co-exposure to manganese (Mn) may enhance neurotoxicity. Objectives: To assess cognitive and behavioral function in adolescents with environmental exposure to Pb and Mn. Methods: In this cross sectional study, cognitive function and behavior were examined in healthy adolescents with environmental exposure to metals. The Wechsler Intelligence Scale for Children (WISC) and the Conners-Wells' Adolescent Self-Report Scale Long Form (CASS:L) were used to assess cognitive and behavioral function, respectively. ALAD polymorphisms rs1800435 and rs1139488 were measured as potential modifiers. Results: We examined 299 adolescents (49.2% females) aged 11-14 years. Blood lead (BPb) averaged 1.71 {mu}g/dL (median 1.5, range 0.44-10.2), mean Blood Manganese (BMn) was 11.1 {mu}g/dL (median 10.9, range 4.00-24.1). Average total IQ was 106.3 (verbal IQ=102, performance IQ=109.3). According to a multiple regression model considering the effect of other covariates, a reduction of about 2.4 IQ points resulted from a two-fold increase of BPb. The Benchmark Level of BPb associated with a loss of 1 IQ-point (BML01) was 0.19 {mu}g/dL, with a lower 95% confidence limit (BMLL01) of 0.11 {mu}g/dL. A very weak correlation resulted between BPb and the ADHD-like behavior (Kendall's tau rank correlation=0.074, p=0.07). No influence of ALAD genotype was observed on any outcome. Manganese was not associated with cognitive and behavioral outcomes, nor was there any interaction with lead. Conclusions: These findings demonstrate that very low level of lead exposure has a significant negative impact on cognitive function in adolescent children. Being an essential micro-nutrient, manganese may not cause cognitive effects at these low exposure levels.

  6. Modular Software-Defined Radio

    Directory of Open Access Journals (Sweden)

    Rhiemeier Arnd-Ragnar

    2005-01-01

    Full Text Available In view of the technical and commercial boundary conditions for software-defined radio (SDR, it is suggestive to reconsider the concept anew from an unconventional point of view. The organizational principles of signal processing (rather than the signal processing algorithms themselves are the main focus of this work on modular software-defined radio. Modularity and flexibility are just two key characteristics of the SDR environment which extend smoothly into the modeling of hardware and software. In particular, the proposed model of signal processing software includes irregular, connected, directed, acyclic graphs with random node weights and random edges. Several approaches for mapping such software to a given hardware are discussed. Taking into account previous findings as well as new results from system simulations presented here, the paper finally concludes with the utility of pipelining as a general design guideline for modular software-defined radio.

  7. Defining and Selecting Independent Directors

    Directory of Open Access Journals (Sweden)

    Eric Pichet

    2017-10-01

    Full Text Available Drawing from the Enlightened Shareholder Theory that the author first developed in 2011, this theoretical paper with practical and normative ambitions achieves a better definition of independent director, while improving the understanding of the roles he fulfils on boards of directors. The first part defines constructs like firms, Governance system and Corporate governance, offering a clear distinction between the latter two concepts before explaining the four main missions of a board. The second part defines the ideal independent director by outlining the objective qualities that are necessary and adding those subjective aspects that have turned this into a veritable profession. The third part defines the ideal process for selecting independent directors, based on nominating committees that should themselves be independent. It also includes ways of assessing directors who are currently in function, as well as modalities for renewing their mandates. The paper’s conclusion presents the Paradox of the Independent Director.

  8. Defining and Classifying Interest Groups

    DEFF Research Database (Denmark)

    Baroni, Laura; Carroll, Brendan; Chalmers, Adam

    2014-01-01

    The interest group concept is defined in many different ways in the existing literature and a range of different classification schemes are employed. This complicates comparisons between different studies and their findings. One of the important tasks faced by interest group scholars engaged...... in large-N studies is therefore to define the concept of an interest group and to determine which classification scheme to use for different group types. After reviewing the existing literature, this article sets out to compare different approaches to defining and classifying interest groups with a sample...... in the organizational attributes of specific interest group types. As expected, our comparison of coding schemes reveals a closer link between group attributes and group type in narrower classification schemes based on group organizational characteristics than those based on a behavioral definition of lobbying....

  9. Low power loss and field-insensitive permeability of Fe-6.5%Si powder cores with manganese oxide-coated particles

    Energy Technology Data Exchange (ETDEWEB)

    Li, Junnan, E-mail: junnanli1991@163.com, E-mail: rzhgong@hust.edu.cn; Wang, Xian; Xu, Xiaojun; Gong, Rongzhou, E-mail: junnanli1991@163.com, E-mail: rzhgong@hust.edu.cn; Feng, Zekun [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Chen, Yajie; Harris, V. G. [Department of Electrical and Computer Engineering, Center for Microwave Magnetic Materials and Integrated Circuits, Northeastern University, Boston, Massachusetts 02115 (United States)

    2015-05-07

    Fe-6.5%Si alloy powders coated with manganese oxides using an innovative in situ process were investigated. The in-situ coating of the insulating oxides was realized with a KMnO{sub 4} solution by a chemical process. The insulating manganese oxides with mixed valance state were verified by X-ray photoelectron spectroscopy analysis. The thickness of the insulating layer on alloy particles was determined to be in a range of 20–210 nm, depending upon the KMnO{sub 4} concentration. The powder core loss and the change in permeability under a DC-bias field were measured at frequencies ranging from 50 to 100 kHz. The experiments indicated that the Fe-6.5%Si powder cores with a 210 nm-thick manganese oxide layer not only showed a low core loss of 459 mW/cm{sup 3} at 100 kHz but also showed a small reduction in permeability (μ(H)/μ(0) = 85% for μ = 42) at a DC-bias field of 80 Oe. This work has defined a novel pathway to realizing low core loss and field-insensitive permeability for Fe-Si powder cores.

  10. Intellectual impairment in school-age children exposed to manganese from drinking water.

    Science.gov (United States)

    Bouchard, Maryse F; Sauvé, Sébastien; Barbeau, Benoit; Legrand, Melissa; Brodeur, Marie-Ève; Bouffard, Thérèse; Limoges, Elyse; Bellinger, David C; Mergler, Donna

    2011-01-01

    Manganese is an essential nutrient, but in excess it can be a potent neurotoxicant. Despite the common occurrence of manganese in groundwater, the risks associated with this source of exposure are largely unknown. Our first aim was to assess the relations between exposure to manganese from drinking water and children's intelligence quotient (IQ). Second, we examined the relations between manganese exposures from water consumption and from the diet with children's hair manganese concentration. This cross-sectional study included 362 children 6-13 years of age living in communities supplied by groundwater. Manganese concentration was measured in home tap water (MnW) and children's hair (MnH). We estimated manganese intake from water ingestion and the diet using a food frequency questionnaire and assessed IQ with the Wechsler Abbreviated Scale of Intelligence. The median MnW in children's home tap water was 34 µg/L (range, 1-2,700 µg/L). MnH increased with manganese intake from water consumption, but not with dietary manganese intake. Higher MnW and MnH were significantly associated with lower IQ scores. A 10-fold increase in MnW was associated with a decrease of 2.4 IQ points (95% confidence interval: -3.9 to -0.9; p < 0.01), adjusting for maternal intelligence, family income, and other potential confounders. There was a 6.2-point difference in IQ between children in the lowest and highest MnW quintiles. MnW was more strongly associated with Performance IQ than Verbal IQ. The findings of this cross-sectional study suggest that exposure to manganese at levels common in groundwater is associated with intellectual impairment in children.

  11. ON DEFINING S-SPACES

    Directory of Open Access Journals (Sweden)

    Francesco Strati

    2013-05-01

    Full Text Available The present work is intended to be an introduction to the Superposition Theory of David Carfì. In particular I shall depict the meaning of his brand new theory, on the one hand in an informal fashion and on the other hand by giving a formal approach of the algebraic structure of the theory: the S-linear algebra. This kind of structure underpins the notion of S-spaces (or Carfì-spaces by defining both its properties and its nature. Thus I shall define the S-triple as the fundamental principle upon which the S-linear algebra is built up.

  12. Study of an alternative system for manganese bath efficiency determination

    International Nuclear Information System (INIS)

    Leite, Sandro Passos

    2010-01-01

    An alternative irradiation system, using radioisotope neutron sources and a small MnSO 4 solution volume, was proposed m this work to determine the Manganese Bath System (MBS) efficiency. The irradiation system was characterized through simulations with the MCNP radiation transport code from the modeling of 252 Cf(f,n) and 238 PuBe(alpha,n) neutron sources in several MnSO 4 solution volumes and different neutron reflector medium for this solution. The parameter calculated in the simulations was the manganese neutron specific capture (MNSC), which is related to the MnSO 4 solution specific activity. From the proposed systems for 252 Cf (f, n) and 238 PuBe (alpha,n) the NSCM was increased hundred times, in relation with that achieved in the LN/LNMRI/IRD MBS system simulation when irradiated by each these neutron sources. During study for irradiation system characterization its concept was verified using a assemble of test irradiation (ATI), which were spherical glass cavities, with few centimeter in radius, filled with MnSO 4 solution, with and without presence of a neutron reflector medium. These TIA were used in four efficiency measurements and the average value was obtained. (author)

  13. Adsorption behavior of lithium from seawater using manganese oxide adsorbent

    International Nuclear Information System (INIS)

    Wajima, Takaaki; Munakata, Kenzo; Uda, Tatsuhiko

    2012-01-01

    The deuterium-tritium (D-T) fusion reactor system is expected to provide the main source of electricity in the future. Large amounts of lithium will be required, dependent on the reactor design concept, and alternative resources should be found to provide lithium inventories for nuclear fusion plants. Seawater has recently become an attractive source of this element and the separation and recovery of lithium from seawater by co-precipitation, solvent extraction and adsorption have been investigated. Amongst these techniques, the adsorption method is suitable for recovery of lithium from seawater, because certain inorganic ion-exchange materials, especially spinel-type manganese oxides, show extremely high selectivity for the lithium ion. In this study, we prepared a lithium adsorbent (HMn 2 O 4 ) by elution of spinel-type lithium di-manganese-tetra-oxide (LiMn 2 O 4 ) and examined the kinetics of the adsorbent for lithium ions in seawater using a pseudo-second-order kinetic model. The intermediate, LiMn 2 O 4 , can be synthesized from LiOH·H 2 O and Mn 3 O 4 , from which the lithium adsorbent can subsequently be prepared via acid treatment., The adsorption kinetics become faster and the amount of lithium adsorbed on the adsorbent increases with increasing solution temperature. The thermodynamic values, ΔG 0 , ΔH 0 and ΔS 0 , indicate that adsorption is an endothermic and spontaneous process. (author)

  14. Photoluminescent properties of nanoporous anodic alumina doped with manganese ions

    Energy Technology Data Exchange (ETDEWEB)

    Gasenkova, I.V. [State Research and Production Association ' Optic, Optoelectronic and Laser techniques”, 68 Nezavisimosti Ave., Minsk 220072 (Belarus); Mukhurov, N.I., E-mail: n.mukhurov@ifanbel.bas-net.by [State Research and Production Association ' Optic, Optoelectronic and Laser techniques”, 68 Nezavisimosti Ave., Minsk 220072 (Belarus); Zhvavyi, S.P.; Kolesnik, E.E. [State Research and Production Association ' Optic, Optoelectronic and Laser techniques”, 68 Nezavisimosti Ave., Minsk 220072 (Belarus); Stupak, A.P. [B.I.Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 68 Nezavisimosti Ave., Minsk 220072 (Belarus)

    2017-05-15

    The results are presented of a comparative study of photoluminescent (PL) properties of unalloyed and Mn-alloyed porous anodic alumina (PAA) subjected to annealing at temperatures in the range of ГђВў{sub a}=200–1300 °ГђВЎ. The possibility of alloying of PAA with metal atoms is illustrated through an example of Mn atoms, and the effect of this impurity on the optical properties of aluminum oxide is examined. Alloying of PAA with Mn ions leads to the formation of complex defects including manganese ions and oxygen vacancies. The difference observed in the spectral dependences of the PL intensity of alloyed and unalloyed specimens is explained by the change in the valence of manganese ions in the complex defects. A decrease has been discovered in the PL intensity of the PL bands and R-lines of Mn and Cr ions in the α-phase under prolonged UV-exposure of the alloyed samples.

  15. Nanorods of manganese oxides: Synthesis, characterization and catalytic application

    Science.gov (United States)

    Yang, Zeheng; Zhang, Yuancheng; Zhang, Weixin; Wang, Xue; Qian, Yitai; Wen, Xiaogang; Yang, Shihe

    2006-03-01

    Single-crystalline nanorods of β-MnO 2, α-Mn 2O 3 and Mn 3O 4 were successfully synthesized via the heat-treatment of γ-MnOOH nanorods, which were prepared through a hydrothermal method in advance. The calcination process of γ-MnOOH nanorods was studied with the help of Thermogravimetric analysis and X-ray powder diffraction. When the calcinations were conducted in air from 250 to 1050 °C, the precursor γ-MnOOH was first changed to β-MnO 2, then to α-Mn 2O 3 and finally to Mn 3O 4. When calcined in N 2 atmosphere, γ-MnOOH was directly converted into Mn 3O 4 at as low as 500 °C. Transmission electron microscopy (TEM) and high-resolution TEM were also used to characterize the products. The obtained manganese oxides maintain the one-dimensional morphology similar to the precursor γ-MnOOH nanorods. Further experiments show that the as-prepared manganese oxide nanorods have catalytic effect on the oxidation and decomposition of the methylene blue (MB) dye with H 2O 2.

  16. Hydrogen-isotopic composition of some hydrous manganese minerals

    International Nuclear Information System (INIS)

    Hariya, Y.; Tsutsumi, M.

    1981-01-01

    Initial data on the hydrogen-isotopic compositions in hydrous Mn minerals from various occurrences fall in a wide range from -298 to -84per thousand, relative to SMOW. deltaD-values of todorokite and cryptomelane from Tertiary deposits show -89 and -150per thousand. 10 A-manganite and delta-MnO 2 from deep-sea nodules have relatively restricted deltaD-values ranging from -96 to -84per thousand. The deltaD-values for manganese bog ores from recent hot springs show almost -105per thousand. It is recognized that the isotopic values obtained for the deep-sea nodules and recent bog ores are slightly different ranged. Manganite and groutite are unique in their hydrogen-isotopic compositions, having the most depleted deltaD-values ranging from -298 to -236per thousand. MnO(OH) minerals are more deuterium-depleted hydrous minerals than any other hydrothermal minerals from various ore deposits. Hydrogen-isotope fractionation factors between manganite and water were experimentally determined to be 0.7894, 0.7958 and 0.8078 at 150 0 , 200 0 and 250 0 C respectively. The present experimental results indicate that if manganites were formed at temperatures below 250 0 C, under isotopic equilibrium conditions most of the manganite mineralization in the Tertiary manganese deposits must have precipitated from meteoric hydrothermal solutions. (Auth.)

  17. Equilibrium Structure of Manganese Trifluoride (MnF3) Molecule

    International Nuclear Information System (INIS)

    Caliskan, M.

    2004-01-01

    The symmetry lowering in manganese trifluoride molecule due to Jahn-Teller distortion was demonstrated in both the experimental and computational results. The molecule does not have D 3 h (or C 3 v) symmetry, rather it has C 2 v symmetry it has been shown from electron-diffraction measurements, that even a molecule of D 3 h symmetry in its equilibrium geometry would appear as having C 3 v symmetry. The manganese trifluoride molecular structures is an example of concerted applications of electron diffraction experiment and computation. It was found two lower energy structures with C 2 v symmetry, one corresponding to the ground state and another corresponding to the transition state. In this work we have calculate the equilibrium structure of the MnF 3 in the C 2 v configuration using the Interionic Force Model. We have compared our results for equilibrium bond lengths and bond angles with measured values from electron diffraction and with the results of quantum chemical calculations. The agreement can be considered as very reasonable

  18. Genomic Prediction of Manganese Efficiency in Winter Barley

    Directory of Open Access Journals (Sweden)

    Florian Leplat

    2016-07-01

    Full Text Available Manganese efficiency is a quantitative abiotic stress trait controlled by several genes each with a small effect. Manganese deficiency leads to yield reduction in winter barley ( L.. Breeding new cultivars for this trait remains difficult because of the lack of visual symptoms and the polygenic features of the trait. Hence, Mn efficiency is a potential suitable trait for a genomic selection (GS approach. A collection of 248 winter barley varieties was screened for Mn efficiency using Chlorophyll (Chl fluorescence in six environments prone to induce Mn deficiency. Two models for genomic prediction were implemented to predict future performance and breeding value of untested varieties. Predictions were obtained using multivariate mixed models: best linear unbiased predictor (BLUP and genomic best linear unbiased predictor (G-BLUP. In the first model, predictions were based on the phenotypic evaluation, whereas both phenotypic and genomic marker data were included in the second model. Accuracy of predicting future phenotype, , and accuracy of predicting true breeding values, , were calculated and compared for both models using six cross-validation (CV schemes; these were designed to mimic plant breeding programs. Overall, the CVs showed that prediction accuracies increased when using the G-BLUP model compared with the prediction accuracies using the BLUP model. Furthermore, the accuracies [] of predicting breeding values were more accurate than accuracy of predicting future phenotypes []. The study confirms that genomic data may enhance the prediction accuracy. Moreover it indicates that GS is a suitable breeding approach for quantitative abiotic stress traits.

  19. Defining and Differentiating the Makerspace

    Science.gov (United States)

    Dousay, Tonia A.

    2017-01-01

    Many resources now punctuate the maker movement landscape. However, some schools and communities still struggle to understand this burgeoning movement. How do we define these spaces and differentiate them from previous labs and shops? Through a multidimensional framework, stakeholders should consider how the structure, access, staffing, and tools…

  20. Indico CONFERENCE: Define the Programme

    CERN Multimedia

    CERN. Geneva; Ferreira, Pedro

    2017-01-01

    In this tutorial you are going to learn how to define the programme of a conference in Indico. The program of your conference is divided in different “tracks”. Tracks represent the subject matter of the conference, such as “Online Computing”, “Offline Computing”, and so on.

  1. Defining and Measuring Chronic Conditions

    Centers for Disease Control (CDC) Podcasts

    This podcast is an interview with Dr. Anand Parekh, U.S. Department of Health and Human Services Deputy Assistant Secretary for Health, and Dr. Samuel Posner, Preventing Chronic Disease Editor in Chief, about the definition and burden of multiple chronic conditions in the United States.

  2. Multiple Perspectives / Multiple Readings

    Directory of Open Access Journals (Sweden)

    Simon Biggs

    2005-01-01

    Full Text Available People experience things from their own physical point of view. What they see is usually a function of where they are and what physical attitude they adopt relative to the subject. With augmented vision (periscopes, mirrors, remote cameras, etc we are able to see things from places where we are not present. With time-shifting technologies, such as the video recorder, we can also see things from the past; a time and a place we may never have visited.In recent artistic work I have been exploring the implications of digital technology, interactivity and internet connectivity that allow people to not so much space/time-shift their visual experience of things but rather see what happens when everybody is simultaneously able to see what everybody else can see. This is extrapolated through the remote networking of sites that are actual installation spaces; where the physical movements of viewers in the space generate multiple perspectives, linked to other similar sites at remote locations or to other viewers entering the shared data-space through a web based version of the work.This text explores the processes involved in such a practice and reflects on related questions regarding the non-singularity of being and the sense of self as linked to time and place.

  3. Population structure of manganese-oxidizing bacteria in stratified soils and properties of manganese oxide aggregates under manganese-complex medium enrichment.

    Directory of Open Access Journals (Sweden)

    Weihong Yang

    Full Text Available Manganese-oxidizing bacteria in the aquatic environment have been comprehensively investigated. However, little information is available about the distribution and biogeochemical significance of these bacteria in terrestrial soil environments. In this study, stratified soils were initially examined to investigate the community structure and diversity of manganese-oxidizing bacteria. Total 344 culturable bacterial isolates from all substrata exhibited Mn(II-oxidizing activities at the range of 1 µM to 240 µM of the equivalent MnO2. The high Mn(II-oxidizing isolates (>50 mM MnO2 were identified as the species of phyla Actinobacteria, Firmicutes and Proteobacteria. Seven novel Mn(II-oxidizing bacterial genera (species, namely, Escherichia, Agromyces, Cellulomonas, Cupriavidus, Microbacterium, Ralstonia, and Variovorax, were revealed via comparative phylogenetic analysis. Moreover, an increase in the diversity of soil bacterial community was observed after the combined enrichment of Mn(II and carbon-rich complex. The phylogenetic classification of the enriched bacteria represented by predominant denaturing gradient gel electrophoresis bands, was apparently similar to culturable Mn(II-oxidizing bacteria. The experiments were further undertaken to investigate the properties of the Mn oxide aggregates formed by the bacterial isolates with high Mn(II-oxidizing activity. Results showed that these bacteria were closely encrusted with their Mn oxides and formed regular microspherical aggregates under prolonged Mn(II and carbon-rich medium enrichment for three weeks. The biotic oxidation of Mn(II to Mn(III/IV by these isolates was confirmed by kinetic examinations. X-ray diffraction assays showed the characteristic peaks of several Mn oxides and rhodochrosite from these aggregates. Leucoberbelin blue tests also verified the Mn(II-oxidizing activity of these aggregates. These results demonstrated that Mn oxides were formed at certain amounts under the

  4. Characteristics and treatment mechanism of mine water with high concentration of iron and manganese

    Energy Technology Data Exchange (ETDEWEB)

    Li, F.; Yang, J.; He, X.; Yang, J.; Tian, T. [Hebei University of Engineering, Handan (China)

    2006-12-15

    The characteristics and treatment of mine water with high concentration or iron and manganese were studied with mine water produced in Jiukuang and Siwan belonging to Hebi Coal Industry Group Co., Ltd. Analysis shows that the mine water is abundant in dissolved oxygen and has high TDS and high turbidity so the mine water does not need aeration. The effect of removal of iron and manganese by coagulation-sedimentation and the influence of filter material and influent water flow rate on effluent quality were investigated. It is shown that the removal rate of iron can reach 90% while removal of manganese can only reach about 20%. The concentration of iron and manganese in the effluent is lower than 0.1 mg/L with filter material of manganese sand which was immersed in KMnO{sub 4} solution at a filtration rate of 7 - 9 m/h. The results show that the layer of activated compound substance membrane formed on the surface of the manganese sand plays an important role in the removal of manganese. 7 refs., 2 figs., 3 tabs.

  5. Effects of aluminum and manganese on the growth of ectomycorrhizal fungi.

    Science.gov (United States)

    Thompson, G W; Medve, R J

    1984-09-01

    Cenococcum graniforme, Suillus luteus, Thelephora terrestris, and three isolates of Pisolithus tinctorius were cultured on modified Melin-Norkrans medium at pH 3.4 and adjusted to 0 to 500 ppm (0 to 500 mug/ml) of aluminum or manganese sulfate. Except for T. terrestris, which was intolerant of aluminum at 150 and 250 to 500 ppm, and P. tinctorius isolate 250, which was intolerant of aluminum at 450 ppm, all fungi showed some growth at all concentrations of aluminum. S. luteus was the most tolerant to aluminum. Manganese was less fungitoxic than aluminum, with all fungi showing at least 65% growth at 500 ppm as compared with the control. C. graniforme was not inhibited at any concentration of manganese, and S. luteus was only affected at 500 ppm. P. tinctorius isolate 230 showed no significant variation in growth when subjected to various concentrations of three forms of manganese salts. Significant differences in growth were detected in response to three aluminum salts, but no detectable pattern was apparent. Genotypic responses to aluminum and manganese were evident for P. tinctorius. Isolates 210 and 230 were more tolerant to manganese than was isolate 250. Aluminum tolerance was in the order of isolate 230 > 210 > 250. Results of in vitro studies concerning tolerance responses of ectomycorrhizal fungi to aluminum and manganese were not consistent with field observations of the successional sequence of these fungi on acid coal spoils.

  6. Effects of aluminum and manganese on the growth of ectomycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, G.W.; Medve, R.J.

    1984-09-01

    Cenococcum graniforme, Suillus luteus, Thelephora terrestris, and three isolates of Pisolithus tinctorius were cultured on modified Melin-Norkrans medium at pH 3.4 and adjusted to 0 to 500 ppm (0 to 500 ..mu..g/ml) of aluminum or manganese sulfate. Except for T. terrestris, which was intolerant of aluminum at 150 and 250 to 500 ppm, and P. tinctorius isolate 250, which was intolerant of aluminum at 450 ppm, all fungi showed some growth at all concentrations of aluminum. S. luteus was the most tolerant to aluminum. Manganese was less fungitoxic than aluminum, with all fungi showing at least 65% growth at 500 ppm as compared with the control. C graniforme was not inhibited at any concentration of manganese, and S. luteus was only affected at 500 ppm. P. tinctorius isolate 230 showed no significant variation in growth when subjected to various concentrations of three forms of manganese salts. Significant differences in growth were detected in response to three aluminum salts, but no detectable pattern was apparent. Genotypic responses to aluminum and manganese were evident for P. tinctorius. Isolates 210 and 230 were more tolerant to manganese than was isolate 250. Aluminum tolerance was in the order of isolate 230 > 210 > 250. Results of in vitro studies concerning tolerance responses of ectomycorrhizal fungi to aluminum and manganese were not consistent with field observations of the successional sequence of these fungi on acid coal spoils. 43 references, 3 tables.

  7. The effect of spices and manganese on meat starter culture activity.

    Science.gov (United States)

    Coventry, M J; Hickey, M W

    1993-01-01

    Three species, two proprietary spice blends and six starter preparations used in commercial salami manufacture were analysed for manganese and magnesium content. A mettwurst spices blend showed the highest levels of manganese (0·77 ppm expressed as effective product level assuming a 1% spice content) while mild and hot paprika and milano blend contained levels of manganese 1 4 - 1 3 lower. Magnesium levels for spices ranged from 3·14 to 25·81 ppm. Only two of the six meat starter cultures showed high levels of manganese (7·77 and 16·12 ppm as effective product level based on inoculation rate) while magnesium levels for all starter cultures did not exceed 0·37 ppm. The pH of salami products made with starter cultures containing no added manganese lagged behind that of products made with added mangenese (5 ppm) by 0·2 pH units at 48 h. The effect of manganese ions on the fermentation rate of starter bacteria was studied further in a salami model system, in the absence and presence of added spices. The mettwurst blend produced greatest stimulation and the milano the least. A level of 1·2 ppm of added manganese was sufficient to achieve an optimal (spices tested in the salami model system. Copyright © 1993. Published by Elsevier Ltd.

  8. Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source

    International Nuclear Information System (INIS)

    Cardoso, Antonio

    1976-01-01

    Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction 55 Mn (n.gamma) 56 Mn, high concentration of manganese in the matrix and short half - life of 56 Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions 56 Fe(n,p) 56 Mn and 59 Co (n, α) 56 were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)

  9. A regional mineralogical study of the manganese-bearing Voelwater subgroup in the northern Cape Province

    International Nuclear Information System (INIS)

    Kleyenstueber, A.S.E.

    1985-11-01

    The Voelwater Subgroup, of the Proterozoic Transvaal Sequence, in the Hotazel area, is preserved in five structurally controlled basins, on the eastern side of the Dimoten syncline. The Subgroup represents a relatively undisturbed unit of mixed volcanogenic - chemical sedimentary rocks. The Hotazel Formation within the Voelwater Subgroup, consists of a finely banded carbonate - silicate - hematite - manganese lutite sequence of banded iron-formation and must be unique in that it contains the world's largest land-based repository of manganese. Twenty-one drill cores, sampled lithologically at intervals of approximately one metre through the total sedimentary sequence, were studied by microscopic, X-ray diffraction and electron microprobe methods. The mineralogy of the Voelwater Subgroup was studied on a regional scale, with the emphasis on the minerals within the manganese beds of the Hotazel Formation. The objective of the study was: a. To study the variation and distrubution of minerals in the various manganese ores on a regional scale. b. To compare the mineralogical differences of the different ores mined, in order to gain a better understanding of their metallurgical behaviour. c. To try to locate high-grade manganese ore target areas for future exploration, with the aid of mineralogical information. d. To try to establish the origin of the manganese in the Voelwater Formation. e. To study the relationship of the manganese units with the adjacent chemical sediments of the Hotazel Formation

  10. AIDS defining disease: Disseminated cryptococcosis

    Directory of Open Access Journals (Sweden)

    Roshan Anupama

    2006-01-01

    Full Text Available Disseminated cryptococcosis is one of the acquired immune deficiency syndrome defining criteria and the most common cause of life threatening meningitis. Disseminated lesions in the skin manifest as papules or nodules that mimic molluscum contagiosum (MC. We report here a human immunodeficiency virus positive patient who presented with MC like lesions. Disseminated cryptococcosis was confirmed by India ink preparation and histopathology. The condition of the patient improved with amphotercin B.

  11. Exploiting a Simple Method for the Determination of Manganese in Polyethylene Lined Tubing for Petroleum and Natural Gas Industries

    Directory of Open Access Journals (Sweden)

    Shao Xiaodong

    2018-01-01

    Full Text Available The polyethylene lined tubing is the key to enabling the industry to meet some of the energy security challenges that nations face today. It is well known that manganese is an important element in polyethylene lined tubing. In this paper, a simple spectrophotometric method was described for the determination of manganese in polyethylene lined tubing. The method was based on the oxidation-reduction reaction between ammonium persulfate and manganese(II producing manganese(VII in the presence of silver nitrate as a catalyst. The characteristic wavelength of maximum absorption of manganese(VII was obtained locating at 530 nm. Under the optimum reaction conditions the absorption value was proportional to the concentration of manganese in the range of 0.2%~1.9% (R2 = 0.9997, and the relative standard deviation was less than 3.0% (n=5. The proposed method was applied successfully to determine manganese in polyethylene lined tubing real samples.

  12. How do people define moderation?

    Science.gov (United States)

    vanDellen, Michelle R; Isherwood, Jennifer C; Delose, Julie E

    2016-06-01

    Eating in moderation is considered to be sound and practical advice for weight maintenance or prevention of weight gain. However, the concept of moderation is ambiguous, and the effect of moderation messages on consumption has yet to be empirically examined. The present manuscript examines how people define moderate consumption. We expected that people would define moderate consumption in ways that justified their current or desired consumption rather than view moderation as an objective standard. In Studies 1 and 2, moderate consumption was perceived to involve greater quantities of an unhealthy food (chocolate chip cookies, gummy candies) than perceptions of how much one should consume. In Study 3, participants generally perceived themselves to eat in moderation and defined moderate consumption as greater than their personal consumption. Furthermore, definitions of moderate consumption were related to personal consumption behaviors. Results suggest that the endorsement of moderation messages allows for a wide range of interpretations of moderate consumption. Thus, we conclude that moderation messages are unlikely to be effective messages for helping people maintain or lose weight. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Transcriptional and biochemical effects of cadmium and manganese on the defense system of Octopus vulgaris paralarvae.

    Science.gov (United States)

    Nicosia, Aldo; Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μg/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn).

  14. Porous nickel hydroxide-manganese dioxide-reduced graphene oxide ternary hybrid spheres as excellent supercapacitor electrode materials.

    Science.gov (United States)

    Chen, Hao; Zhou, Shuxue; Wu, Limin

    2014-06-11

    This paper reports the first nickel hydroxide-manganese dioxide-reduced graphene oxide (Ni(OH)2-MnO2-RGO) ternary hybrid sphere powders as supercapacitor electrode materials. Due to the abundant porous nanostructure, relatively high specific surface area, well-defined spherical morphology, and the synergetic effect of Ni(OH)2, MnO2, and RGO, the electrodes with the as-obtained Ni(OH)2-MnO2-RGO ternary hybrid spheres as active materials exhibited significantly enhanced specific capacitance (1985 F·g(-1)) and energy density (54.0 Wh·kg(-1)), based on the total mass of active materials. In addition, the Ni(OH)2-MnO2-RGO hybrid spheres-based asymmetric supercapacitor also showed satisfying energy density and electrochemical cycling stability.

  15. Neurobehavioral function in school-age children exposed to manganese in drinking water.

    Science.gov (United States)

    Oulhote, Youssef; Mergler, Donna; Barbeau, Benoit; Bellinger, David C; Bouffard, Thérèse; Brodeur, Marie-Ève; Saint-Amour, Dave; Legrand, Melissa; Sauvé, Sébastien; Bouchard, Maryse F

    2014-12-01

    Manganese neurotoxicity is well documented in individuals occupationally exposed to airborne particulates, but few data are available on risks from drinking-water exposure. We examined associations of exposure from concentrations of manganese in water and hair with memory, attention, motor function, and parent- and teacher-reported hyperactive behaviors. We recruited 375 children and measured manganese in home tap water (MnW) and hair (MnH). We estimated manganese intake from water ingestion. Using structural equation modeling, we estimated associations between neurobehavioral functions and MnH, MnW, and manganese intake from water. We evaluated exposure-response relationships using generalized additive models. After adjusting for potential confounders, a 1-SD increase in log10 MnH was associated with a significant difference of -24% (95% CI: -36, -12%) SD in memory and -25% (95% CI: -41, -9%) SD in attention. The relations between log10 MnH and poorer memory and attention were linear. A 1-SD increase in log10 MnW was associated with a significant difference of -14% (95% CI: -24, -4%) SD in memory, and this relation was nonlinear, with a steeper decline in performance at MnW > 100 μg/L. A 1-SD increase in log10 manganese intake from water was associated with a significant difference of -11% (95% CI: -21, -0.4%) SD in motor function. The relation between log10 manganese intake and poorer motor function was linear. There was no significant association between manganese exposure and hyperactivity. Exposure to manganese in water was associated with poorer neurobehavioral performances in children, even at low levels commonly encountered in North America.

  16. Biological manganese removal from acid mine drainage in constructed wetlands and prototype bioreactors.

    Science.gov (United States)

    Hallberg, Kevin B; Johnson, D Barrie

    2005-02-01

    Mine drainage waters vary considerably in the range and concentration of heavy metals they contain. Besides iron, manganese is frequently present at elevated concentrations in waters draining both coal and metal mines. Passive treatment systems (aerobic wetlands and compost bioreactors) are designed to remove iron by biologically induced oxidation/precipitation. Manganese, however, is problematic as it does not readily form sulfidic minerals and requires elevated pH (>8) for abiotic oxidation of Mn (II) to insoluble Mn (IV). As a result, manganese removal in passive remediation systems is often less effective than removal of iron. This was found to be the case at the pilot passive treatment plant (PPTP) constructed to treat water draining the former Wheal Jane tin mine in Cornwall, UK, where effective removal of manganese occurred only in one of the three rock filter components of the composite systems over a 1-year period of monitoring. Water in the two rock filter systems where manganese removal was relatively poor was generally system. These differences in water chemistry and manganese removal were due to variable performances in the compost bioreactors that feed the rock filter units in the composite passive systems at Wheal Jane. An alternative approach for removing soluble manganese from mine waters, using fixed bed bioreactors, was developed. Ferromanganese nodules (about 2 cm diameter), collected from an abandoned mine adit in north Wales, were used to inoculate the bioreactors (working volume ca. 700 ml). Following colonization by manganese-oxidizing microbes, the aerated bioreactor catalysed the removal of soluble manganese, via oxidation of Mn (II) and precipitation of the resultant Mn (IV) in the bioreactor, in synthetic media and mine water from the Wheal Jane PPTP. Such an approach has potential application for removing soluble Mn from mine streams and other Mn-contaminated water courses.

  17. Terminology, the importance of defining.

    Science.gov (United States)

    van Mil, J W Foppe; Henman, Martin

    2016-06-01

    Multiple terms and definitions exist to describe specific aspects of pharmacy practice and service provision. This commentary explores the reasons for different interpretations of words and concepts in pharmaceutical care and pharmacy practice research. Reasons for this variation can be found in language, culture, profession and may also depend on developments over time. A list of words is provided where the authors think that currently multiple interpretations are possible. To make sure that the reader understands the essence, it seems imperative that authors include a definition of the topics that they actually study in their papers, and that they clearly cite existing definitions or refer to collections of definitions such as existing glossaries. It is important that presenters, authors and reviewers of pharmacy practice papers pay more attention to this aspect of describing studies.

  18. Defining and Measuring Chronic Conditions

    Centers for Disease Control (CDC) Podcasts

    2013-05-20

    This podcast is an interview with Dr. Anand Parekh, U.S. Department of Health and Human Services Deputy Assistant Secretary for Health, and Dr. Samuel Posner, Preventing Chronic Disease Editor in Chief, about the definition and burden of multiple chronic conditions in the United States.  Created: 5/20/2013 by Preventing Chronic Disease (PCD), National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 5/20/2013.

  19. Determination of iron, copper, manganese and zinc in the soils, grapes and wines of the Azores

    Directory of Open Access Journals (Sweden)

    María Teresa Ribeiro de Lima

    2004-06-01

    Full Text Available This paper describes the determination of iron, copper, manganese and zinc in the soils, grapes and wines of the three viticultural regions of the Azores. Iron, copper and zinc were determined by flame atomic absorption spectrometry and manganese by graphite furnace atomic absorption. The concentrations of the four elements differed in soils of the three regions; there was no difference in the concentration in grapes, whereas significant differences were observed for the wines as regards the amounts of iron, manganese and zinc. The concentrations of these four elements in wine correspond with the mean values observed for other European regions.

  20. Effect of mass density on surface morphology of electrodeposited manganese oxide films

    Science.gov (United States)

    Singh, Avtar; Kumar, Davinder; Thakur, Anup; Kaur, Raminder

    2018-05-01

    This work focus on high surface area morphology of manganese oxide films which are currently required for electrochemical capacitor electrode to enhance their performance. Electrodeposition of manganese oxide films was carried out using Chronoamperometry for different deposition time ranging from 30 to 120 sec. Cronoamperomertic I-T integrated data have been used to analyze active mass of all electrodeposited films. Morphological study of the deposited films with different mass was carried out through scanning electron microscopy. Film deposited for 30 sec time show highest porous morphology than others. Manganese oxide films with high porosity are suitable for electrochemical capacitor electrode.

  1. Adhesive wear of iron chromium nickel silicon manganese molybdenum niobium alloys with duplex structure

    International Nuclear Information System (INIS)

    Lugscheider, E.; Deppe, E.; Ambroziak, A.; Melzer, A.

    1991-01-01

    Iron nickel chromium manganese silicon and iron chromium nickel manganese silicon molybdenum niobium alloys have a so-called duplex structure in a wide concentration range. This causes an excellent resistance to wear superior in the case of adhesive stress with optimized concentrations of manganese, silicon, molybdenum and niobium. The materials can be used for welded armouring structures wherever cobalt and boron-containing alloy systems are not permissible, e.g. in nuclear science. Within the framework of pre-investigations for manufacturing of filling wire electrodes, cast test pieces were set up with duplex structure, and their wear behavior was examined. (orig.) [de

  2. Effect of Organic Binders on The Quality of Manganese Ore Sinter Fines Briquettes

    International Nuclear Information System (INIS)

    Mohamed, F. M.; Ahmed, Y.M.Z.; Shalabi, M. E. H.

    2004-01-01

    Sinai Manganese Company imports the manganese ore sinter from abroad for ferromanganese alloy production. Large quantities of manganese ore sinter fines are produced in this process. These fines must be agglomerated to a suitable size in order to be reused for charging the electric arc furnace. The aim of this work is studying the briquetting ability of these fines using organic binders such as starch and bitumen. The results showed that, the suitable briquettes were produced with the addition of 5 % of starch and 20% H 2 O under pressure 3 ton/cm 2 or 8 % bitumen under pressure 4 ton/cm 2 and 3 days curing time

  3. Research on rejection performance of reverse osmosis to manganese in simulated radioactive wastewater

    International Nuclear Information System (INIS)

    Kong Jinsong; Wang Xiaowei

    2012-01-01

    In order to reveal the performance of reverse osmosis applied in the radioactive wastewater treatment, treatment experiments are carried out on a pilot RO equipment using wastewater containing manganese nuclide. Results show that the rejection ratio of RO to manganese is almost not influenced by the operation pressure and the ration of reclaiming, and has no direct relation with the salt rejection ratio. The ratio of manganese rejection is more than 95% and can meet the requirement on the disposal of radioactive wastewater produced by pressurized water reactors. (authors)

  4. Reconfigurable, Cognitive Software-Defined Radio

    Science.gov (United States)

    Bhat, Arvind

    2015-01-01

    Software-defined radio (SDR) technology allows radios to be reconfigured to perform different communication functions without using multiple radios to accomplish each task. Intelligent Automation, Inc., has developed SDR platforms that switch adaptively between different operation modes. The innovation works by modifying both transmit waveforms and receiver signal processing tasks. In Phase I of the project, the company developed SDR cognitive capabilities, including adaptive modulation and coding (AMC), automatic modulation recognition (AMR), and spectrum sensing. In Phase II, these capabilities were integrated into SDR platforms. The reconfigurable transceiver design employs high-speed field-programmable gate arrays, enabling multimode operation and scalable architecture. Designs are based on commercial off-the-shelf (COTS) components and are modular in nature, making it easier to upgrade individual components rather than redesigning the entire SDR platform as technology advances.

  5. Gold-manganese nanoparticles for targeted diagnostic and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Murph, Simona Hunyadi [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-11-10

    Imagine the possibility of non-invasive, non-radiation based Magnetic resonance imaging (MRI) in combating cardiac disease. Researchers at the Savannah River National Laboratory (SRNL) are developing a process that would use nanotechnology in a novel, targeted approach that would allow MRIs to be more descriptive and brighter, and to target specific organs. Researchers at SRNL have discovered a way to use multifunctional metallic gold-manganese nanoparticles to create a unique, targeted positive contrast agent. SRNL Senior Scientist Dr. Simona Hunyadi Murph says she first thought of using the nanoparticles for cardiac disease applications after learning that people who survive an infarct exhibit up to 15 times higher rate of developing chronic heart failure, arrhythmias and/or sudden death compared to the general population. Without question, nanotechnology will revolutionize the future of technology. The development of functional nanomaterials with multi-detection modalities opens up new avenues for creating multi-purpose technologies for biomedical applications.

  6. The sonochemical arylation of malonic esters mediated by manganese triacetate.

    Science.gov (United States)

    Meciarova, M; Toma, S; Luche, J L

    2001-04-01

    The intermolecular arylation of malonate esters in acetic acid solution in the presence of manganese(III) triacetate is known to proceed via an Electron Transfer mechanism. Under sonication, this reaction undergoes only minor changes. In contrast, the intramolecular reaction of dimethyl alpha-(3-phenylpropyl)malonate provides a new case of sonochemical switching, with the formation of compounds 7-9, while conventional thermal conditions generate only the bicyclic compound 6. Reactions using the more powerful oxidant, cerium ammonium nitrate are governed by the formation of the nitrate ester 11. Compounds 7-9 are isolated in yields lower than with MnTA, and in proportions depending on the conditions, thermal or sonochemical.

  7. Thermal decomposition study of manganese sulfide (MnS) nanoparticles

    Science.gov (United States)

    Tailor, Jiten P.; Khimani, Ankurkumar J.; Chaki, Sunil H.; Deshpande, M. P.

    2018-05-01

    The as-synthesized manganese sulfide (MnS) nanoparticles were used for the thermal study. The nanoparticles were synthesized by simple wet chemical route at ambient temperature. The photoelectron binding energy and chemical composition of MnS nanoparticles was analyzed by X-ray photoelectron spectroscopy (XPS). The thermogravimetric (TG), differential thermogravimetric (DTG) and differential thermal analysis (DTA) were carried out on the as-synthesized MnS nanoparticles. The thermocurves were recorded in inert N2 atmosphere in the temperature range of ambient to 1173 K. The heating rates employed were 5, 10, 15 and 20 K/min. The thermodynamic parameters like activation energy (Ea), enthalpy change (ΔH), entropy change (ΔS) and change in Gibbs free energy (ΔG) of as-synthesized MnS nanoparticles were determined using Kissinger method. The obtained XPS and thermal results are discussed.

  8. Monte Carlo study of double exchange interaction in manganese oxide

    Energy Technology Data Exchange (ETDEWEB)

    Naa, Christian Fredy, E-mail: chris@cphys.fi.itb.ac.id [Physics Department, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jalan Ganesha 10 Bandung (Indonesia); Unité de Dynamique et Structure des Matérioux Moléculaires, Université Littoral Côte d’Opale, Maison de la Reserche Blaise Pascal 50, rue Ferdinand Buisson, Calais, France email (France); Suprijadi,, E-mail: supri@fi.itb.ac.id; Viridi, Sparisoma, E-mail: dudung@fi.itb.ac.id; Djamal, Mitra, E-mail: mitra@fi.itb.ac.id [Physics Department, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jalan Ganesha 10 Bandung (Indonesia); Fasquelle, Didier, E-mail: didier.fasquelle@univ-littoral.fr [Unité de Dynamique et Structure des Matérioux Moléculaires, Université Littoral Côte d’Opale, Maison de la Reserche Blaise Pascal 50, rue Ferdinand Buisson, Calais, France email (France)

    2015-09-30

    In this paper we study the magnetoresistance properties attributed by double exchange (DE) interaction in manganese oxide by Monte Carlo simulation. We construct a model based on mixed-valence Mn{sup 3+} and Mn{sup 4+} on the general system of Re{sub 2/3}Ae{sub 1/3}MnO{sub 3} in two dimensional system. The conduction mechanism is based on probability of e{sub g} electrons hopping from Mn{sup 3+} to Mn{sup 4+}. The resistivity dependence on temperature and the external magnetic field are presented and the validity with related experimental results are discussed. We use the resistivity power law to fit our data on metallic region and basic activated behavior on insulator region. On metallic region, we found our result agree well with the quantum theory of DE interaction. From general arguments, we found our simulation agree qualitatively with experimental results.

  9. Dynamics analysis of extraction of manganese intensified by electric field

    Science.gov (United States)

    Ma, Wenrui; Tao, Changyuan; Li, Huizhan; Liu, Zuohua; Liu, Renlong

    2018-06-01

    In this study, a process reinforcement technology for leaching process of pyrolusite was developed. The electric field was introduced to decrease reaction temperature and improve the leaching rate of pyrolusite. The mechanisms of electric field intensifying leaching process of pyrolusite were investigated through X-ray diffraction (XRD), and Brunauer Emmett Teller (BET) in detail. The results showed that the electric field could decrease obviously the apparent activation energy of leaching process of pyrolusite. The apparent activation energy of the leaching of pyrolusite intensified by electric field was calculated to be 53.76 kJ.mol-1. In addition, the leaching efficiency of manganese was effectively increased by 10% to 20% than that without electric field under the same conditions. This was because that the electron conduit between Fe (II)/Fe (III) and pyrite was dredged effectively by electric field.

  10. Manganese Oxide on Carbon Fabric for Flexible Supercapacitors

    Directory of Open Access Journals (Sweden)

    Jianfeng Zhang

    2016-01-01

    Full Text Available We report the fabrication of uniform large-area manganese oxide (MnO2 nanosheets on carbon fabric which oxidized using O2 plasma treatment (MnO2/O2-carbon fabric via electrodeposition process and their implementation as supercapacitor electrodes. Electrochemical measurements demonstrated that MnO2/O2-carbon fabric exhibited capacitance as high as 275 F/g at a scan rate of 5 mV/s; in addition, it showed an excellent cycling performance (less than 20% capacitance loss after 10,000 cycles. All the results suggest that MnO2/O2-carbon fabric is a promising electrode material which has great potential for application on flexible supercapacitors.

  11. Powder addition assessment of manganese residue ceramic matrix coating

    International Nuclear Information System (INIS)

    Conceicao, A.C.R. da; Santos, O.C.; Leao, M.A.

    2016-01-01

    The use of recycled materials in the composition of new products follows the production's worldwide trending, meeting new technological requirements and environmental concerns. This work aims to utilize the residue of manganese dust on ceramic mass for the production of ceramic coating. The raw materials were characterized by both x-ray fluorescence and diffraction. The powder residue added to clay in the percentage of 0%, 5%, 10% and 15% (measured in weight) was compressed by a uniaxial pressing of 30MPa and the sintering temperatures were 900°, 1000° and 1100°. The samples were analysed in relation to flexural strength, bulk density, water absorption and linear shrinkage. The microstructural variation was also analysed by x-ray diffraction and electron microscopy. The results showed that there is a viability for the production of porcelain ceramic coating (A3 and A4 formulations) and stoneware (A2 formulation) according to the specification of technical standards. author)

  12. A Low Spin Manganese(IV) Nitride Single Molecule Magnet.

    Science.gov (United States)

    Ding, Mei; Cutsail, George E; Aravena, Daniel; Amoza, Martín; Rouzières, Mathieu; Dechambenoit, Pierre; Losovyj, Yaroslav; Pink, Maren; Ruiz, Eliseo; Clérac, Rodolphe; Smith, Jeremy M

    2016-09-01

    Structural, spectroscopic and magnetic methods have been used to characterize the tris(carbene)borate compound PhB(MesIm) 3 Mn≡N as a four-coordinate manganese(IV) complex with a low spin ( S = 1/2) configuration. The slow relaxation of the magnetization in this complex, i.e. its single-molecule magnet (SMM) properties, is revealed under an applied dc field. Multireference quantum mechanical calculations indicate that this SMM behavior originates from an anisotropic ground doublet stabilized by spin-orbit coupling. Consistent theoretical and experiment data show that the resulting magnetization dynamics in this system is dominated by ground state quantum tunneling, while its temperature dependence is influenced by Raman relaxation.

  13. Lipophilic manganese porphyrin crosses blood-brain barrier

    International Nuclear Information System (INIS)

    Nelson, J.A.; Cegnar, J.; Spence, A.M.; Richards, T.L.; Golden, R.N.; Muzi, M.

    1987-01-01

    Most reports on manganese porphyrins as MR imaging contrast agents have focused on a water-soluble compound, Mn-TPPS4. Phototherapy researchers have noted that lipophilic components of hematoporphyrin derivative sensitize normal brain tissue to light-stimulated photodestruction. This observation suggests that a lipophilic paramagnetic agent might be useful for brain contrast enhancement. The current experiments were designed to test the MR imaging effects of a lipid-soluble compound, Mn-mesoporphyrin. An intravenous injection of 0.05 μmoles/kg was administered to rats with a well-characterized astrocytic glioma implanted into the right cerebral hemisphere. MR imaging experiments performed at 2 T on a General Electric CSI-II system revealed T1 relaxation shortening in both normal brain and tumor. Delayed images at 24 hours revealed persistent selective contrast agent enhancement at the gross tumor site

  14. Characterization of manganese tetraarylthiosubstituted phthalocyanines self assembled monolayers

    International Nuclear Information System (INIS)

    Matemadombo, Fungisai; Durmus, Mahmut; Togo, Chamunorwa; Limson, Janice; Nyokong, Tebello

    2009-01-01

    Manganese tetraarylthiosubstituted phthalocyanines (complexes 1-5) have been deposited on Au electrode surfaces through the self assembled monolayer (SAM) technique. SAM characteristics reported in this work are: ion barrier factor (∼1); interfacial capacitance (303-539 μF cm -2 ) and surface coverage (1.06 x 10 -10 -2.80 x 10 -10 mol cm -2 ). Atomic force microscopy was employed in characterizing a SAM. SAMs of complexes 1-5 were employed to detect L-cysteine (with limit of detection ranging from 2.83 x 10 -7 to 3.14 x 10 -7 M at potentials of 0.68-0.75 V vs. Ag|AgCl) and nitrite (limit of detection ranging from 1.78 x 10 -7 to 3.02 x 10 -7 M at potentials of 0.69-0.76 V vs. Ag|AgCl).

  15. Photoinduced charge transfer phase transition in cesium manganese hexacyanoferrate

    International Nuclear Information System (INIS)

    Matsuda, Tomoyuki; Tokoro, Hiroko; Hashimoto, Kazuhito; Ohkoshi, Shin-ichi

    2007-01-01

    Cesium manganese hexacyanoferrate, Cs 1.51 Mn[Fe(CN) 6 ], shows a thermal phase transition between Mn II -NC-Fe III [high-temperature (HT) phase] and Mn III -NC-Fe II [low-temperature (LT) phase] with phase transition temperatures of 170 K (HT→LT) and 230 K (LT→HT). The LT phase shows ferromagnetism with Curie temperature of 7 K and coercive field of 60 Oe. Irradiating with 532 nm laser light converts the LT phase into the photoinduced (PI) phase, which does not have spontaneous magnetization. The electronic state of the PI phase corresponds to that of the HT phase and the relaxation temperature from the PI to the LT phase is observed at 90 K

  16. The aluminosilicate fraction of North Pacific manganese nodules

    Science.gov (United States)

    Bischoff, J.L.; Piper, D.Z.; Leong, K.

    1981-01-01

    Nine nodules collected from throughout the deep North Pacific were analyzed for their mineralogy and major-element composition before and after leaching with Chester-Hughes solution. Data indicate that the mineral phillipsite accounts for the major part (> 75%) of the aluminosilicate fraction of all nodules. It is suggested that formation of phillipsite takes place on growing nodule surfaces coupled with the oxidation of absorbed manganous ion. All the nodules could be described as ternary mixtures of amorphous iron fraction (Fe-Ti-P), manganese oxide fraction (Mn-Mg Cu-Ni), and phillipsite fraction (Al-Si-K-Na), these fractions accounting for 96% of the variability of the chemical composition. ?? 1981.

  17. Voltammetric determination of arsenic in high iron and manganese groundwaters.

    Science.gov (United States)

    Gibbon-Walsh, Kristoff; Salaün, Pascal; Uroic, M Kalle; Feldmann, Joerg; McArthur, John M; van den Berg, Constant M G

    2011-09-15

    Determination of the speciation of arsenic in groundwaters, using cathodic stripping voltammetry (CSV), is severely hampered by high levels of iron and manganese. Experiments showed that the interference is eliminated by addition of EDTA, making it possible to determine the arsenic speciation on-site by CSV. This work presents the CSV method to determine As(III) in high-iron or -manganese groundwaters in the field with only minor sample treatment. The method was field-tested in West-Bengal (India) on a series of groundwater samples. Total arsenic was subsequently determined after acidification to pH 1 by anodic stripping voltammetry (ASV). Comparative measurements by ICP-MS as reference method for total As, and by HPLC for its speciation, were used to corroborate the field data in stored samples. Most of the arsenic (78±0.02%) was found to occur as inorganic As(III) in the freshly collected waters, in accordance with previous studies. The data shows that the modified on-site CSV method for As(III) is a good measure of water contamination with As. The EDTA was also found to be effective in stabilising the arsenic speciation for longterm sample storage at room temperature. Without sample preservation, in water exposed to air and sunlight, the As(III) was found to become oxidised to As(V), and Fe(II) oxidised to Fe(III), removing the As(V) by adsorption on precipitating Fe(III)-hydroxides within a few hours. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Using exposure windows to explore an elusive biomarker: blood manganese.

    Science.gov (United States)

    Baker, Marissa G; Stover, Bert; Simpson, Christopher D; Sheppard, Lianne; Seixas, Noah S

    2016-05-01

    We sought to understand the time course between exposure to manganese (Mn) and uptake into the blood, to allow a more meaningful interpretation of exposure biomarker data, and to determine the utility of blood as a biomarker of Mn exposure. Welder trainees were monitored over the course of a five-quarter training program. Each quarter, trainees gave eight blood samples and had personal air monitoring four times. A mixed model was fit to obtain estimates of airborne exposure by welding type (fixed effect), adjusted for subject (random effect). Considering weekends and days absent as zero exposure, estimated exposures were summed over various exposure windows and related to measured blood manganese (MnB) using a mixed model. A relationship consistent with zero was found between MnB and modeled 1 or 7 days of exposure. After 30 days of preceding exposure, a 1 mg-days/m(3) increase in air Mn is associated with a 0.57 ng/mL increase in MnB (95% CI -0.04, 1.19). Considering a 90-day exposure window and a cumulative exposure window, a 1 mg-days/m(3) increase in air Mn is associated with a 0.26 (95% CI 0.005, 0.51) and 0.09 (95% CI 0.006, 0.17) ng/mL increase in MnB, respectively. From this analysis, MnB may begin to act as a biomarker of Mn exposure over longer time periods, or at higher levels of exposure. This novel study design allowed investigation of how MnB relates to different time windows of exposure, representing the most robust Mn exposure assessment in the biomarker literature.

  19. Hair Manganese as an Exposure Biomarker among Welders.

    Science.gov (United States)

    Reiss, Boris; Simpson, Christopher D; Baker, Marissa G; Stover, Bert; Sheppard, Lianne; Seixas, Noah S

    2016-03-01

    Quantifying exposure and dose to manganese (Mn) containing airborne particles in welding fume presents many challenges. Common biological markers such as Mn in blood or Mn in urine have not proven to be practical biomarkers even in studies where positive associations were observed. However, hair Mn (MnH) as a biomarker has the advantage over blood and urine that it is less influenced by short-term variability of Mn exposure levels because of its slow growth rate. The objective of this study was to determine whether hair can be used as a biomarker for welders exposed to manganese. Hair samples (1cm) were collected from 47 welding school students and individual air Mn (MnA) exposures were measured for each subject. MnA levels for all days were estimated with a linear mixed model using welding type as a predictor. A 30-day time-weighted average MnA (MnA30d) exposure level was calculated for each hair sample. The association between MnH and MnA30d levels was then assessed. A linear relationship was observed between log-transformed MnA30d and log-transformed MnH. Doubling MnA30d exposure levels yields a 20% (95% confidence interval: 11-29%) increase in MnH. The association was similar for hair washed following two different wash procedures designed to remove external contamination. Hair shows promise as a biomarker for inhaled Mn exposure given the presence of a significant linear association between MnH and MnA30d levels. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  20. Microstructure and properties of manganese dioxide films prepared by electrodeposition

    International Nuclear Information System (INIS)

    Jacob, G. Moses; Zhitomirsky, I.

    2008-01-01

    Nanostructured manganese dioxide films were obtained by galvanostatic, pulse and reverse pulse electrodeposition from 0.01 to 0.1 M KMnO 4 solutions. The deposition yield was investigated by in situ monitoring the deposit mass using a quartz crystal microbalance (QCM). Obtained films were studied by electron microscopy, X-ray diffraction analysis, energy dispersive spectroscopy, thermogravimetric and differential thermal analysis. The QCM and electron microscopy data were utilized for the investigation of deposition kinetics and film formation mechanism. It was shown that the deposition rate and film microstructure could be changed by variation of deposition conditions. The method allowed the fabrication of dense or porous films. The thickness of dense films was limited to ∼0.1 μm due to the insulating properties of manganese dioxide and film cracking, attributed to drying shrinkage. Porous and crack-free 1-2 μm films were obtained using galvanostatic or reverse pulse deposition from 0.02 M KMnO 4 solutions. It was shown that film porosity is beneficial for the charge transfer during deposition and crack prevention in thick films. Moreover, porous nanostructured films showed good capacitive behavior for applications in electrochemical supercapacitors. The porous nanostructured films prepared in the reverse pulse regime showed higher specific capacitance (SC) compared to the SC of the galvanostatic films. The highest SC of 279 F/g in a voltage window of 1 V was obtained in 0.1 M Na 2 SO 4 solutions at a scan rate of 2 mV/s

  1. Synthesis and structural characterization of manganese olivine lithium phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Herrera Robles, Joel O. [Basic Science Department, IIT, Universidad Autónoma de Ciudad Juárez, Av. del Charro 460 norte Cd. Juárez, Chih. C.P. 32310 (Mexico); Fuentes Cobas, Luis E. [Centro de Investigación en Materiales Avanzados CIMAV, Complejo Industrial, M. Cervantes 120, Chihuahua C.P. 31109 (Mexico); Díaz de la Torre, Sebastián [Instituto Politécnico Nacional, Centro de Investigación e Innovación Tecnológica CIITEC, Azcapotzalco, México, D.F. C.P. 02250 (Mexico); Camacho Montes, Héctor, E-mail: hcamacho@uacj.mx [Basic Science Department, IIT, Universidad Autónoma de Ciudad Juárez, Av. del Charro 460 norte Cd. Juárez, Chih. C.P. 32310 (Mexico); Elizalde Galindo, José T.; García Casillas, Perla E.; Rodríguez González, Claudia A. [Basic Science Department, IIT, Universidad Autónoma de Ciudad Juárez, Av. del Charro 460 norte Cd. Juárez, Chih. C.P. 32310 (Mexico); Álvarez Contreras, Lorena [Centro de Investigación en Materiales Avanzados CIMAV, Complejo Industrial, M. Cervantes 120, Chihuahua C.P. 31109 (Mexico)

    2015-09-15

    Highlights: • LiMnPO{sub 4} was obtained by sol gel method and crystallization in reducing atmosphere. • Magnetic and electric properties are reported for LiMnPO{sub 4}. • Electrochemical properties are also found and enhanced by adding carbon. • SEM and HRTEM show the submicron powder nature. • The multifunctional behavior of LiMnPO{sub 4} is experimentally demonstrated. - Abstract: The manganese olivine lithium phosphate is a multifunctional material. If carbon is added to form a composite LiMnPO{sub 4}–C, electrochemical properties can be enhanced, making this material a good candidate for battery cathode. High magnetic susceptibility is reported for this compound at room temperature. In this work, the magnetic response was measured through a Field Cooling/Zero Field Cooling technique at temperature below 100 K. Weak ferroelectric properties at room temperature were measured. Even though, the promising applications and the interesting properties of this system, the attention received in the literature is relatively low. The synthesis of this material is difficult because of the rapid manganese oxidation and the need of a reducing atmosphere. In fact, only few authors report the synthesis of the pure phase. In the present work, nanostructured LiMnPO{sub 4} is obtained by sol gel chemical method and according to X-ray diffraction patterns, pure LiMnPO{sub 4} is obtained after calcination in a reducing atmosphere (10% H{sub 2} – 90% Ar). Nanostructured LiMnPO{sub 4} is a material with very interesting properties that deserves attentions.

  2. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Roetter, Daniel Enrique Lucani

    2015-01-01

    Software Defined Networking (SDN) and Network Coding (NC) are two key concepts in networking that have garnered a large attention in recent years. On the one hand, SDN's potential to virtualize services in the Internet allows a large flexibility not only for routing data, but also to manage....... This paper advocates for the use of SDN to bring about future Internet and 5G network services by incorporating network coding (NC) functionalities. The inherent flexibility of both SDN and NC provides a fertile ground to envision more efficient, robust, and secure networking designs, that may also...

  3. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Hansen, Jonas; Roetter, Daniel Enrique Lucani; Krigslund, Jeppe

    2015-01-01

    Software defined networking has garnered large attention due to its potential to virtualize services in the Internet, introducing flexibility in the buffering, scheduling, processing, and routing of data in network routers. SDN breaks the deadlock that has kept Internet network protocols stagnant...... for decades, while applications and physical links have evolved. This article advocates for the use of SDN to bring about 5G network services by incorporating network coding (NC) functionalities. The latter constitutes a major leap forward compared to the state-of-the- art store and forward Internet paradigm...

  4. (Re)Defining Salesperson Motivation

    DEFF Research Database (Denmark)

    Khusainova, Rushana; de Jong, Ad; Lee, Nick

    2018-01-01

    The construct of motivation is one of the central themes in selling and sales management research. Yet, to-date no review article exists that surveys the construct (both from an extrinsic and intrinsic motivation context), critically evaluates its current status, examines various key challenges...... apparent from the extant research, and suggests new research opportunities based on a thorough review of past work. The authors explore how motivation is defined, major theories underpinning motivation, how motivation has historically been measured, and key methodologies used over time. In addition......, attention is given to principal drivers and outcomes of salesperson motivation. A summarizing appendix of key articles in salesperson motivation is provided....

  5. Defining Usability of PN Services

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Ahola, Titta; Fleury, Alexandre

    In this deliverable usability and user experience are defined in relation to MAGNET Beyond technologies, and it is described how the main MAGNET Beyond concepts can be evaluated through the involvement of users. The concepts include the new "Activity based communication approach" for interacting...... with the MAGNET Beyond system, as well as the core concepts: Personal Network, Personal Network-Federation, Service Discovery, User Profile Management, Personal Network Management, Privacy and Security and Context Awareness. The overall plans for the final usability evaluation are documented based on the present...

  6. Multiple sclerosis

    Science.gov (United States)

    ... indwelling catheter Osteoporosis or thinning of the bones Pressure sores Side effects of medicines used to treat the ... Daily bowel care program Multiple sclerosis - discharge Preventing pressure ulcers Swallowing problems Images Multiple sclerosis MRI of the ...

  7. Simultaneous stripping recovery of ammonia-nitrogen and precipitation of manganese from electrolytic manganese residue by air under calcium oxide assist.

    Science.gov (United States)

    Chen, Hongliang; Liu, Renlong; Shu, Jiancheng; Li, Wensheng

    2015-01-01

    Leaching tests of electrolytic manganese residue (EMR) indicated that high contents of soluble manganese and ammonia-nitrogen posed a high environmental risk. This work reports the results of simultaneous stripping recovery of ammonia-nitrogen and precipitation of manganese by air under calcium oxide assist. The ammonia-nitrogen stripping rate increased with the dosage of CaO, the air flow rate and the temperature of EMR slurry. Stripped ammonia-nitrogen was absorbed by a solution of sulfuric acid and formed soluble (NH4)2SO4 and (NH4)3H(SO4)3. The major parameters that effected soluble manganese precipitation were the dosage of added CaO and the slurry temperature. Considering these two aspects, the efficient operation conditions should be conducted with 8 wt.% added CaO, 60°C, 800 mL min(-1) air flow rate and 60-min reaction time. Under these conditions 99.99% of the soluble manganese was precipitated as Mn3O4, which was confirmed by XRD and SEM-EDS analyses. In addition, the stripping rate of ammonia-nitrogen was 99.73%. Leaching tests showed the leached toxic substances concentrations of the treated EMR met the integrated wastewater discharge standard of China (GB8978-1996).

  8. A magnetic route to measure the average oxidation state of mixed-valent manganese in manganese oxide octahedral molecular sieves (OMS).

    Science.gov (United States)

    Shen, Xiong-Fei; Ding, Yun-Shuang; Liu, Jia; Han, Zhao-Hui; Budnick, Joseph I; Hines, William A; Suib, Steven L

    2005-05-04

    A magnetic route has been applied for measurement of the average oxidation state (AOS) of mixed-valent manganese in manganese oxide octahedral molecular sieves (OMS). The method gives AOS measurement results in good agreement with titration methods. A maximum analysis deviation error of +/-7% is obtained from 10 sample measurements. The magnetic method is able to (1) confirm the presence of mixed-valent manganese and (2) evaluate AOS and the spin states of d electrons of both single oxidation state and mixed-valent state Mn in manganese oxides. In addition, the magnetic method may be extended to (1) determine AOS of Mn in manganese oxide OMS with dopant "diamagnetic" ions, such as reducible V5+ (3d0) ions, which is inappropriate for the titration method due to interference of redox reactions between these dopant ions and titration reagents, such as KMnO4, (2) evaluate the dopant "paramagnetic" ions that are present as clusters or in the OMS framework, and (3) determine AOS of other mixed-valent/single oxidation state ion systems, such as Mo3+(3d3)-Mo4+(3d2) systems and Fe3+ in FeCl3.

  9. Expressiveness and definability in circumscription

    Directory of Open Access Journals (Sweden)

    Francicleber Martins Ferreira

    2011-06-01

    Full Text Available We investigate expressiveness and definability issues with respect to minimal models, particularly in the scope of Circumscription. First, we give a proof of the failure of the Löwenheim-Skolem Theorem for Circumscription. Then we show that, if the class of P; Z-minimal models of a first-order sentence is Δ-elementary, then it is elementary. That is, whenever the circumscription of a first-order sentence is equivalent to a first-order theory, then it is equivalent to a finitely axiomatizable one. This means that classes of models of circumscribed theories are either elementary or not Δ-elementary. Finally, using the previous result, we prove that, whenever a relation Pi is defined in the class of P; Z-minimal models of a first-order sentence Φ and whenever such class of P; Z-minimal models is Δ-elementary, then there is an explicit definition ψ for Pi such that the class of P; Z-minimal models of Φ is the class of models of Φ ∧ ψ. In order words, the circumscription of P in Φ with Z varied can be replaced by Φ plus this explicit definition ψ for Pi.

  10. Defining Quality in Undergraduate Education

    Directory of Open Access Journals (Sweden)

    Alison W. Bowers

    2018-01-01

    Full Text Available Objectives: This research brief explores the literature addressing quality in undergraduate education to identify what previous research has said about quality and to offer future directions for research on quality in undergraduate education. Method: We conducted a scoping review to provide a broad overview of existing research. Using targeted search terms in academic databases, we identified and reviewed relevant academic literature to develop emergent themes and implications for future research. Results: The exploratory review of the literature revealed a range of thoughtful discussions and empirical studies attempting to define quality in undergraduate education. Many publications highlighted the importance of including different stakeholder perspectives and presented some of the varying perceptions of quality among different stakeholders. Conclusions: While a number of researchers have explored and written about how to define quality in undergraduate education, there is not a general consensus regarding a definition of quality in undergraduate education. Past research offers a range of insights, models, and data to inform future research. Implication for Theory and/or Practice: We provide four recommendations for future research to contribute to a high quality undergraduate educational experience. We suggest more comprehensive systematic reviews of the literature as a next step.

  11. Distributed controller clustering in software defined networks.

    Directory of Open Access Journals (Sweden)

    Ahmed Abdelaziz

    Full Text Available Software Defined Networking (SDN is an emerging promising paradigm for network management because of its centralized network intelligence. However, the centralized control architecture of the software-defined networks (SDNs brings novel challenges of reliability, scalability, fault tolerance and interoperability. In this paper, we proposed a novel clustered distributed controller architecture in the real setting of SDNs. The distributed cluster implementation comprises of multiple popular SDN controllers. The proposed mechanism is evaluated using a real world network topology running on top of an emulated SDN environment. The result shows that the proposed distributed controller clustering mechanism is able to significantly reduce the average latency from 8.1% to 1.6%, the packet loss from 5.22% to 4.15%, compared to distributed controller without clustering running on HP Virtual Application Network (VAN SDN and Open Network Operating System (ONOS controllers respectively. Moreover, proposed method also shows reasonable CPU utilization results. Furthermore, the proposed mechanism makes possible to handle unexpected load fluctuations while maintaining a continuous network operation, even when there is a controller failure. The paper is a potential contribution stepping towards addressing the issues of reliability, scalability, fault tolerance, and inter-operability.

  12. Distributed controller clustering in software defined networks.

    Science.gov (United States)

    Abdelaziz, Ahmed; Fong, Ang Tan; Gani, Abdullah; Garba, Usman; Khan, Suleman; Akhunzada, Adnan; Talebian, Hamid; Choo, Kim-Kwang Raymond

    2017-01-01

    Software Defined Networking (SDN) is an emerging promising paradigm for network management because of its centralized network intelligence. However, the centralized control architecture of the software-defined networks (SDNs) brings novel challenges of reliability, scalability, fault tolerance and interoperability. In this paper, we proposed a novel clustered distributed controller architecture in the real setting of SDNs. The distributed cluster implementation comprises of multiple popular SDN controllers. The proposed mechanism is evaluated using a real world network topology running on top of an emulated SDN environment. The result shows that the proposed distributed controller clustering mechanism is able to significantly reduce the average latency from 8.1% to 1.6%, the packet loss from 5.22% to 4.15%, compared to distributed controller without clustering running on HP Virtual Application Network (VAN) SDN and Open Network Operating System (ONOS) controllers respectively. Moreover, proposed method also shows reasonable CPU utilization results. Furthermore, the proposed mechanism makes possible to handle unexpected load fluctuations while maintaining a continuous network operation, even when there is a controller failure. The paper is a potential contribution stepping towards addressing the issues of reliability, scalability, fault tolerance, and inter-operability.

  13. Hydrogeochemistry in a relatively unmodified subtropical catchment: Insights regarding the health and aesthetic risks of manganese

    Directory of Open Access Journals (Sweden)

    Adam K. Rose

    2017-10-01

    New hydrological insights for region: Results show that the hydrogeochemistry of Baffle Creek was predominantly driven by rain events, with differing responses to varying magnitudes of rain and discharge. Following a flushing event, dissolved aluminium and nitrate increased in the surface and drinking water, whereas manganese and ammonia were undetectable in the drinking water and occurred only in small concentrations in the surface waters. In contrast, when rainfall events occurred without an associated flush, manganese, iron and ammonia concentrations increased in the drinking water. The hydrochemistry of manganese and iron in the supply chain infrastructure was strongly positively correlated with ammonia, and aluminium correlated with nitrate concentrations. Currently the drinking water supply does not pose a threat to chronic manganese exposure for humans, however elevated concentrations are experienced periodically; and may become more problematic under climate change scenarios.

  14. Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite

    Directory of Open Access Journals (Sweden)

    Endah Retnaningrum

    2017-07-01

    Full Text Available The present research was conducted to investigate sulphate and manganese removal from synthetic wastewater. The continuous laboratory scale of down-flow fluidized-bed reactor (DFBR using sulphate reducing bacteria (SRB consortium and Indonesian natural zeolite as a bacterial support material was designed. At 9 days operation, maximum sulphate and manganese removal was observed to be 23% and 15.4%, respectively. The pH values were also changed to neutral. The population of SRB increased which effect on the raising of their activity for removing sulphate and manganese. Using the scanning electronic microscopy (SEM, it was observed that natural zeolite possesses excellent physical characteristics as a bacterial support material in DFBR. The imaging SEM result of SRB consortium on zeolite surface clearly showed the developed SRB biofilm on that particle. Analysis result of EDX confirmed that manganese was precipitated as manganese–sulfides.

  15. On-line determination of manganese in solid seafood samples by flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Yebra, M.C.; Moreno-Cid, A.

    2003-01-01

    Manganese is extracted on-line from solid seafood samples by a simple continuous ultrasound-assisted extraction system (CUES). This system is connected to an on-line manifold, which permits the flow-injection flame atomic absorption spectrometric determination of manganese. Optimisation of the continuous leaching procedure is performed by an experimental design. The proposed method allows the determination of manganese with a relative standard deviation of 0.9% for a sample containing 23.4 μg g -1 manganese (dry mass). The detection limit is 0.4 μg g -1 (dry mass) for 30 mg of sample and the sample throughput is ca. 60 samples per hour. Accurate results are obtained by measuring TORT-1 certified reference material. The procedure is finally applied to mussel, tuna, sardine and clams samples

  16. Insulin sensitivity to trace metals (Chromium, manganese) in type 2 diabetic patients and diabetic individuals

    International Nuclear Information System (INIS)

    Hajra, B.; Orakzai, S.A.; Faryal, U.; Hassan, M.

    2016-01-01

    Background: Diabetes mellitus constitutes one of the most important problems in developing and non-developing countries. The purpose of the study to estimate the concentrations of Chromium and Manganese in diabetic and non-diabetic population of Hazara division. The cross sectional comparative study was carried out on one hundred blood samples of Type 2 Diabetic patients collected non-randomly from Ayub Teaching Hospital and one hundred normal healthy controls from Women Medical College Abbottabad from September 2014 to April 2015. Methods: The study included two hundred subjects. Among them 100 were diabetic and 100 non diabetic respectively. The blood samples were collected from Ayub Medical College, Abbottabad. The serum Chromium and Manganese levels were determined by Atomic Absorption spectrophotometer. Results: Serum Chromium and Manganese levels were decreased in diabetic and increased in non-diabetic patients. Conclusion: Low serum level of Chromium and manganese were found in diabetic patients as compare to non-diabetic individuals. (author)

  17. Influence of distribution characteristics and associated seabed features on exploitation of cobalt-rich manganese deposits

    Digital Repository Service at National Institute of Oceanography (India)

    Yamazaki, T.; Sharma, R.; Tsurusaki, K.

    Method of exploitation, selection of mine site and desing of mining system of cobalt-rich manganese deposits on seamounts would be greatly influenced by the distribution characteristics as well as the associated seabed features, wuch as the seabed...

  18. Manganese and selenium concentrations in cerebrospinal fluid of seriously ill children.

    Science.gov (United States)

    Franěk, Tomáš; Kotaška, Karel; Průša, Richard

    2017-11-01

    The homeostasis of essential trace elements such as selenium and manganese may be altered in patients with severe diseases of various etiologies (trauma brain injuries, tumors, leukemias, lymphomas, neurological diseases). Concentration of manganese and selenium were determined in cerebrospinal fluid by electrothermal atomic absorption spectrometry in 50 hospitalized children with various clinical ethiologies including oncological, neurological, and brain related diseases. The concentrations of manganese in cerebrospinal fluid of children were 0.97±0.67 μg/L. The concentrations of selenium were 13.3±3.5 μg/L. The concentrations were similar as published in adults. The values did not correlated with the age, gender and severity of the disease. We evaluated values of selenium and manganese in cerebrospinal fluid of seriously diseased children. © 2017 Wiley Periodicals, Inc.

  19. Stability of a novel synthetic amorphous manganese oxide in contrasting soils

    Czech Academy of Sciences Publication Activity Database

    Ettler, V.; Knytl, V.; Komárek, M.; Della Puppa, L.; Bordas, F.; Mihaljevič, M.; Klementová, Mariana; Šebek, O.

    2014-01-01

    Roč. 214, FEB (2014), s. 2-9 ISSN 0016-7061 Institutional support: RVO:61388980 Keywords : Amorphous manganese oxide * Stability * Soils * Chemical stabilization * Pollution Subject RIV: CA - Inorganic Chemistry Impact factor: 2.772, year: 2014

  20. Characterization of chloroplast phosphoproteins controlling manganese use efficiency using quantitative proteomics

    DEFF Research Database (Denmark)

    Petersen, Jørgen; Sprenger, Richard Remko; Rogowska-Wrzesinska, Adelina

    Manganese is important for molecular functions in plants, i.e. as a co-factor in enzymes and in the oxygen evolving complex of photosystem II, located like most of the photosynthetic machinery, in the thylakoid membranes of chloroplasts. Soils that lack plant available micronutrients such as mang......Manganese is important for molecular functions in plants, i.e. as a co-factor in enzymes and in the oxygen evolving complex of photosystem II, located like most of the photosynthetic machinery, in the thylakoid membranes of chloroplasts. Soils that lack plant available micronutrients...... involved in manganese use efficiency, focusing on the phosphoproteome from thylakoid preparations from two barley genotypes, manganese efficient (Vanessa) and inefficient (Antonia) genotype. Experimental: By monitoring the photosynthetic efficiency (Fv/Fm) a decline in activity is observed as a consequence...

  1. Inter-relationship between nuclei and gross characteristics of manganese nodules, Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, C; Iyer, S.D.; Hazra, S.

    More than 200 samples of manganese nodules from the Central Indian Ocean Basin (CIOB) were studied for their different parameters. The study included various aspects such as morphology, texture, mineralogy, and composition of the nodules. The nuclei...

  2. Sequential analysis: manganese, catecholamines, and L-dopa induced dyskinesia. [Cat's brain

    Energy Technology Data Exchange (ETDEWEB)

    Papavasiliou, P S; Miller, S T; Cotzias, G C; Kraner, H W; Hsieh, R S

    1975-01-01

    The paper specifies methodology for the sequential determination of manganese and catecholamines in selfsame brain samples and shows correlations between them. Small samples were obtained from five regions of brain of cats that had received either saline or levodopa. The doses of levodopa were varied so that although all animals reacted, some developed dyskinesia while others did not. Each sample was first analyzed nondestructively for manganese and then destructively for dopa and dopamine; thus errors inherent in analyzing separate samples, due to the structural heterogeneity of the brain, were avoided. Statistically significant correlations were found (1) between levodopa-induced dyskinesia and the concentrations of dopamine and manganese in some of the regions analysed, and (2) between the concentrations of dopamine and of manganese in the caudates of the cats receiving the highest doses of levodopa. (auth)

  3. Synthesis, structure and magnetism of manganese and iron dipicolinates with N,N '-donor ligands

    Czech Academy of Sciences Publication Activity Database

    Uhrecký, Róbert; Svoboda, I.; Růžičková, Z.; Koman, M.; Dlháň, L.; Pavlík, J.; Moncol, J.; Boca, R.

    2015-01-01

    Roč. 425, JAN (2015), s. 134-144 ISSN 0020-1693 Institutional support: RVO:61388980 Keywords : Manganese * Iron * Dipicolinate complexes * Crystal structure * Magnetism Subject RIV: CA - Inorganic Chemistry Impact factor: 1.918, year: 2015

  4. Design improvements in box dredges to enhance the collection of manganese nodules

    Digital Repository Service at National Institute of Oceanography (India)

    Fernando, V.; Sonawane, A.V.

    Design of three box dredges along with the technique and modifications effected to anable bulk sampling of manganese nodules is presented. Incorporation of a sled, angled cutting edges, retention plates and increased size of the dredge resulted...

  5. Evaluation of Co-rich manganese deposits by image analysis and photogrammetric techniques

    Digital Repository Service at National Institute of Oceanography (India)

    Yamazaki, T.; Sharma, R.; Tsurusaki, K.

    Stereo-seabed photographs of Co-rich manganese deposits on a mid-Pacific seamount, were analysed using an image analysis software for coverage estimation and size classification of nodules, and a photogrammetric software for calculation of height...

  6. Morphological and interlayer geochemical studies on manganese nodules from the southwestern Carlsberg ridge

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Rajamanickam, G.V.; Karisiddaiah, S.M.; Siddiquie, H.N.

    Mixed facies of manganese nodules from the southwestern Carlberg Ridge have been analysed for Mn, Fe, Ni, Cu, Co and Zn. Seventy one analyses including the averages presented for outer layer, inner layer and near-core material. Morphological studies...

  7. Rapidly reversible redox transformation in nanophase manganese oxides at room temperature triggered by changes in hydration.

    Science.gov (United States)

    Birkner, Nancy; Navrotsky, Alexandra

    2014-04-29

    Chemisorption of water onto anhydrous nanophase manganese oxide surfaces promotes rapidly reversible redox phase changes as confirmed by calorimetry, X-ray diffraction, and titration for manganese average oxidation state. Surface reduction of bixbyite (Mn2O3) to hausmannite (Mn3O4) occurs in nanoparticles under conditions where no such reactions are seen or expected on grounds of bulk thermodynamics in coarse-grained materials. Additionally, transformation does not occur on nanosurfaces passivated by at least 2% coverage of what is likely an amorphous manganese oxide layer. The transformation is due to thermodynamic control arising from differences in surface energies of the two phases (Mn2O3 and Mn3O4) under wet and dry conditions. Such reversible and rapid transformation near room temperature may affect the behavior of manganese oxides in technological applications and in geologic and environmental settings.

  8. Benthic environmental baseline investigations in the manganese nodule area of the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Nath, B.N.; Gupta, S.M.; Ansari, Z.A.

    In order to exploit the manganese nodule deposits in future, an assessment of the environmental impact due to potential mining activity, has been undertaken in the Central Indian Basin Under this programme, seabed surveys in five selected areas have...

  9. The origin of ferro-manganese oxide coated pumice from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Pearce, N.J.G.; Parthiban, G.; Smith, V.C.; Mudholkar, A.V.; Rao, N.R

    Pumice clasts, partially and fully coated with ferro-manganese oxide from the Central Indian Ocean Basin (CIOB) were analysed for major, trace and rare earth elements; and glass and mineral grain chemistry to assess their possible source...

  10. Organometallic complexes of thiocarbanilides and substituted thiocarbanilides using manganese (II) chloride

    International Nuclear Information System (INIS)

    Babiker, Musa Elaballa Mohamed

    2000-01-01

    Organo-metallic complexes of substituted thiocarbanilide using manganese (II) chloride were prepared, these are: (VIII) 3:3'-Dichloro thiocarbanilide. Manganese (II) chloride. (IX) 3:3'-Dimethyl thiocarbanilide. Manganese (II) chloride. (X) 2:2'-dimethyl thiocarbanilide. Manganese (II) chloride. These compounds are coloured, soluble in most organic solvents, insoluble in water, decomposed by hot solvents. The physical properties of compounds (IX) and (X) were studied by UV and IR spectra, and the physical properties of compound (VIII) were studied by UV, IR, mass spectra and NMR. The molecular weight of the compound (VIII) was determined by three different methods; Rast's camphor method, mass spectra and the nitrogen contents. The stoichiometry of the reaction was found to be 2:1, and the coordination is from sulphur atom more than nitrogen.(Author)

  11. Coulometric microdetermination of organic compounds with manganese(III) and cerium(IV)

    International Nuclear Information System (INIS)

    Chateau-Gosselin, M.; Patriarche, G.J.

    1977-01-01

    The oxidation of compounds such as hydroquinon, p-aminophenol, paracetamol and phenacetin was performed using cerium(IV) and manganese(III) coulometrically electrogenerated. Quantitative results obtained are excellent even at the microscale level. (author)

  12. Manganese: it turns iron into steel (and does so much more)

    Science.gov (United States)

    Cannon, William F.

    2014-01-01

    Manganese is a common ferrous metal with atomic weight of 25 and the chemical symbol Mn. It constitutes roughly 0.1 percent of the Earth’s crust, making it the 12th most abundant element. Its early uses were limited largely to pigments and oxidants in chemical processes and experiments, but the significance of manganese to human societies exploded with the development of modern steelmaking technology in the 1860s. U.S consumption of manganese is about 500,000 metric tons each year, predominantly by the steel industry. Because manganese is essential and irreplaceable in steelmaking and its global mining industry is dominated by just a few nations, it is considered one of the most critical mineral commodities for the United States.

  13. Chelation in metal intoxication. V. Lowering of manganese content in poisoned rat organs

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, S K; Mathur, A K

    1976-01-01

    Metal chelation has been considered useful in the management of manganese poisoning to a considerable extent. Our own studies in this direction have shown that some polyaminocarboxylic acids and a few amino acids are effective in not only removing manganese from the vital organs of experimentally poisoned animals but also in restoring certain metal induced biochemical and histological changes in such organs. Further, the success of p-aminosalicylic acid (PAS), a chemotherapeutic agent for tuberculosis, in manganese mobilization has led us to examine some other structurally related compounds together with a few other possible metal binding agents for their ability to remove excess metal from the organs, their sub-cellular fractions and blood cells of manganese administered rats and to investigate if there exists any relationship between the structure of such compounds and their metal mobilizing capacity. The present communication deals with the results of these investigations.

  14. Manganese in the shelf sediments off the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, P.S.N.; Rao, Ch.M.; Reddy, C.V.G.

    shows that the contribution is practically from land. Higher rates of sedimentation was also observed on the inner shelf particularly between Alleppey and Karwar. The sediments in the slope region were slightly enriched in their manganese content than...

  15. High Manganese Tolerance and Biooxidation Ability of Serratia marcescens Isolated from Manganese Mine Water in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Natália R. Barboza

    2017-10-01

    Full Text Available Manganese is an important metal for the maintenance of several biological functions, but it can be toxic in high concentrations. One of the main forms of human exposure to metals, such as manganese (Mn, is the consumption of solar salt contaminated. Mn-tolerant bacteria could be used to decrease the concentration of this metal from contaminated sites through safer environmental-friendly alternative technology in the future. Therefore, this study was undertaken to isolate and identify Mn resistant bacteria from water samples collected from a Mn mine in the Iron Quadrangle region (Minas Gerais, Brazil. Two bacterial isolates were identified as Serratia marcescens based on morphological, biochemical, 16S rDNA gene sequencing and phylogeny analysis. Maximum resistance of the selected isolates against increasing concentrations of Mn(II, up to 1200 mg L-1 was determined in solid media. A batch assay was developed to analyze and quantify the Mn removal capacities of the isolates. Biological Mn removal capacities of over 55% were detected for both isolates. Whereas that mechanism like biosorption, precipitation and oxidation could be explaining the Mn removal, we seek to give an insight into some of the molecular mechanisms adopted by S. marcescens isolates. For this purpose, the following approaches were adopted: leucoberbelin blue I assay, Mn(II oxidation by cell-free filtrate and electron microscopy and energy-dispersive X-ray spectroscopy analyses. Overall, these results indicate that S. marcescens promotes Mn removal in an indirect mechanism by the formation of Mn oxides precipitates around the cells, which should be further explored for potential biotechnological applications for water recycling both in hydrometallurgical and mineral processing operations.

  16. Evaluation of the contamination and the exposure to manganese from the combustion of methylcyclopentadienyl manganese tricarbonyl (MMT) in unleaded fuel

    International Nuclear Information System (INIS)

    Zayed, J.; Loranger, S.; Kennedy, G.

    1994-01-01

    Methylcyclopentadienyl manganese tricarbonyl (MMT) has been used since 1976 in Canada as an antiknock additive in gasoline to replace tetraethyl lead. Combustion of MMT in the engine forms manganese oxides, mainly Mn 3 O 4 , which are emitted into the environment. Since human exposure to Mn is associated with various health problems, a research program was initiated to evaluate the degree of contamination and the fate of Mn originating from MMT combustion. Four projects were conducted as part of this program: chronological evaluation of atmospheric Mn concentrations in Montreal from 1981 to 1992; comparative evaluation of Mn concentrations in soil and vegetation exposed to MMT-generated Mn; evaluation of the pigeon as an ecological indicator of MMT-generated Mn contamination; and evaluation of the occupational and environmental exposure of workers exposed to Mn oxides. Methodologies and results from these projects are reveiwed. In Montreal, atmospheric Mn levels are significantly higher at monitoring stations in areas of high traffic density. A large drop in Mn levels starting in 1991 was attributed to closure of a ferromanganese plant ca 25 km from Montreal. Field tests in experimental bean and oat plots also showed higher Mn levels in soil and plants in areas of high traffic. While pigeons from Montreal had higher Mn levels in tissues than rural pigeons, it is nevertheless impossible to link such levels directly to Mn originating from MMT. Mechanics were found to be exposed to higher atmospheric Mn concentrations than blue collar workers. Blood Mn levels in those workers were normal, but Mn concentrations in hair of mechanics were significantly higher than those found in a control group. 13 refs., 3 figs., 5 tabs

  17. Associations of iron metabolism genes with blood manganese levels: a population-based study with validation data from animal models

    Directory of Open Access Journals (Sweden)

    Claus Henn Birgit

    2011-11-01

    Full Text Available Abstract Background Given mounting evidence for adverse effects from excess manganese exposure, it is critical to understand host factors, such as genetics, that affect manganese metabolism. Methods Archived blood samples, collected from 332 Mexican women at delivery, were analyzed for manganese. We evaluated associations of manganese with functional variants in three candidate iron metabolism genes: HFE [hemochromatosis], TF [transferrin], and ALAD [δ-aminolevulinic acid dehydratase]. We used a knockout mouse model to parallel our significant results as a novel method of validating the observed associations between genotype and blood manganese in our epidemiologic data. Results Percentage of participants carrying at least one copy of HFE C282Y, HFE H63D, TF P570S, and ALAD K59N variant alleles was 2.4%, 17.7%, 20.1%, and 6.4%, respectively. Percentage carrying at least one copy of either C282Y or H63D allele in HFE gene was 19.6%. Geometric mean (geometric standard deviation manganese concentrations were 17.0 (1.5 μg/l. Women with any HFE variant allele had 12% lower blood manganese concentrations than women with no variant alleles (β = -0.12 [95% CI = -0.23 to -0.01]. TF and ALAD variants were not significant predictors of blood manganese. In animal models, Hfe-/- mice displayed a significant reduction in blood manganese compared with Hfe+/+ mice, replicating the altered manganese metabolism found in our human research. Conclusions Our study suggests that genetic variants in iron metabolism genes may contribute to variability in manganese exposure by affecting manganese absorption, distribution, or excretion. Genetic background may be critical to consider in studies that rely on environmental manganese measurements.

  18. Synthesis of manganese stearate for high density polyethylene (HDPE) and its biodegradation

    Science.gov (United States)

    Aras, Neny Rasnyanti M.; Arcana, I. Made

    2015-09-01

    An oxidant additive is one type of additive used for oxo-biodegradable polymers. This additive was prepared by reaction multivalent transition metals and fatty acids to accelerate the degradation process of polymers by providing a thermal treatment or irradiation with light. This study focused on the synthesis of manganese stearate as an additive for application in High Density Polyethylene (HDPE), and the influence of manganese stearate on the characteristics of HDPE including their biodegradability. Manganese stearate was synthesized by the reaction of stearic acid with sodium hydroxide, and sodium stearate formed was reacted with manganese chloride tetrahydrate to form manganese stearate with a melting point of 100-110 °C. Based on the FTIR spectrum showed absorption peak at wave number around 1560 cm-1 which is an asymmetric vibration of CO functional group that binds to the manganese. The films of oxo-biodegradable polymer were prepared by blending HDPE and manganese stearate additives at various concentrations with using the polymer melting method, followed heating at a temperature of 50°C and 70°C for 10 days. The characterizations of the oxo-biodegradable polymers were carried out by analysis the functional groups (FTIR and ATR),thermal properties (TGA), surface properties (SEM), as well as analysis of the biodegradability (the biodegradation test by using activated sludge, % weight loss). Based on COi indicate that the additive of manganese stearate is active in oxidizing polymer by heating treatment. Results of biodegradation by microorganisms from activated sludge showed that the percentage weight loss of polymers increase with the increasing incubation time and the concentration of manganese stearate in HDPE. Biodegradability of HDPE with the addition of manganese stearate and followed by heating at a higher temperature was better observed. The highest percentage weight loss was obtained at the polymer with concentration of 0.2% manganese stearate

  19. Synthesis of manganese stearate for high density polyethylene (HDPE) and its biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Aras, Neny Rasnyanti M., E-mail: neny.rasnyanti@gmail.com; Arcana, I Made, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132 (Indonesia)

    2015-09-30

    An oxidant additive is one type of additive used for oxo-biodegradable polymers. This additive was prepared by reaction multivalent transition metals and fatty acids to accelerate the degradation process of polymers by providing a thermal treatment or irradiation with light. This study focused on the synthesis of manganese stearate as an additive for application in High Density Polyethylene (HDPE), and the influence of manganese stearate on the characteristics of HDPE including their biodegradability. Manganese stearate was synthesized by the reaction of stearic acid with sodium hydroxide, and sodium stearate formed was reacted with manganese chloride tetrahydrate to form manganese stearate with a melting point of 100-110 °C. Based on the FTIR spectrum showed absorption peak at wave number around 1560 cm{sup −1} which is an asymmetric vibration of CO functional group that binds to the manganese. The films of oxo-biodegradable polymer were prepared by blending HDPE and manganese stearate additives at various concentrations with using the polymer melting method, followed heating at a temperature of 50°C and 70°C for 10 days. The characterizations of the oxo-biodegradable polymers were carried out by analysis the functional groups (FTIR and ATR),thermal properties (TGA), surface properties (SEM), as well as analysis of the biodegradability (the biodegradation test by using activated sludge, % weight loss). Based on COi indicate that the additive of manganese stearate is active in oxidizing polymer by heating treatment. Results of biodegradation by microorganisms from activated sludge showed that the percentage weight loss of polymers increase with the increasing incubation time and the concentration of manganese stearate in HDPE. Biodegradability of HDPE with the addition of manganese stearate and followed by heating at a higher temperature was better observed. The highest percentage weight loss was obtained at the polymer with concentration of 0.2% manganese

  20. Activation of a water molecule coordinated to manganese: four study cases

    International Nuclear Information System (INIS)

    Lassalle-Kaiser, B.

    2008-10-01

    The daunting energy consumption of western societies calls for the development of renewable energies. Among them, hydrogen stands as a major candidate. The cleanest way of producing hydrogen is water electro- or photolysis. This reaction is carried out in natural photosynthesis by a manganese-oxo cluster, the functioning of which remains unknown. Insight into this mechanism would greatly help the search for low-cost water splitting catalysts. Our contribution to this field is the understanding of the fundamental processes that govern the activation of water by manganese complexes. This manuscript describes our attempts to generate electrochemically mononuclear manganese(IV) complexes bearing a fully deprotonated water molecule (oxo ligand). We have studied four different cases, which reflect different possible coordination spheres capable of stabilizing such species. In the first chapter, we will give a brief overview of the present energetic challenges faced by western societies. In the second chapter, we will present general considerations about manganese chemistry and a description of the structure and functioning of the water oxidizing enzyme. We will also describe the basic requirements for the splitting of water and present the goals of our work. In the third chapter, we will present the synthesis of a new family of tetradentate ligands, together with the synthesis and full characterization of the corresponding nickel(II) complexes. The first results obtained with the manganese analogue will also be shown. Chapter four presents the formation and the full characterization of a mononuclear manganese(IV)-oxo complex, by electrochemical oxidation of a manganese(II)-aqua complex. We will present different pathways to generate this species and show which intermediates are involved in this 2 e - , 2 H + reaction. Chapter five describes the formation of a mononuclear manganese(IV) complex, by electrochemical oxidation of a manganese(III)-hydroxo complex. The

  1. Synthesis of manganese stearate for high density polyethylene (HDPE) and its biodegradation

    International Nuclear Information System (INIS)

    Aras, Neny Rasnyanti M.; Arcana, I Made

    2015-01-01

    An oxidant additive is one type of additive used for oxo-biodegradable polymers. This additive was prepared by reaction multivalent transition metals and fatty acids to accelerate the degradation process of polymers by providing a thermal treatment or irradiation with light. This study focused on the synthesis of manganese stearate as an additive for application in High Density Polyethylene (HDPE), and the influence of manganese stearate on the characteristics of HDPE including their biodegradability. Manganese stearate was synthesized by the reaction of stearic acid with sodium hydroxide, and sodium stearate formed was reacted with manganese chloride tetrahydrate to form manganese stearate with a melting point of 100-110 °C. Based on the FTIR spectrum showed absorption peak at wave number around 1560 cm −1 which is an asymmetric vibration of CO functional group that binds to the manganese. The films of oxo-biodegradable polymer were prepared by blending HDPE and manganese stearate additives at various concentrations with using the polymer melting method, followed heating at a temperature of 50°C and 70°C for 10 days. The characterizations of the oxo-biodegradable polymers were carried out by analysis the functional groups (FTIR and ATR),thermal properties (TGA), surface properties (SEM), as well as analysis of the biodegradability (the biodegradation test by using activated sludge, % weight loss). Based on COi indicate that the additive of manganese stearate is active in oxidizing polymer by heating treatment. Results of biodegradation by microorganisms from activated sludge showed that the percentage weight loss of polymers increase with the increasing incubation time and the concentration of manganese stearate in HDPE. Biodegradability of HDPE with the addition of manganese stearate and followed by heating at a higher temperature was better observed. The highest percentage weight loss was obtained at the polymer with concentration of 0.2% manganese

  2. Defining the "normal" postejaculate urinalysis.

    Science.gov (United States)

    Mehta, Akanksha; Jarow, Jonathan P; Maples, Pat; Sigman, Mark

    2012-01-01

    Although sperm have been shown to be present in the postejaculate urinalysis (PEU) of both fertile and infertile men, the number of sperm present in the PEU of the general population has never been well defined. The objective of this study was to describe the semen and PEU findings in both the general and infertile population, in order to develop a better appreciation for "normal." Infertile men (n = 77) and control subjects (n = 71) were prospectively recruited. Exclusion criteria included azoospermia and medications known to affect ejaculation. All men underwent a history, physical examination, semen analysis, and PEU. The urine was split into 2 containers: PEU1, the initial voided urine, and PEU2, the remaining voided urine. Parametric statistical methods were applied for data analysis to compare sperm concentrations in each sample of semen and urine between the 2 groups of men. Controls had higher average semen volume (3.3 ± 1.6 vs 2.0 ± 1.4 mL, P sperm concentrations (112 million vs 56.2 million, P = .011), compared with infertile men. The presence of sperm in urine was common in both groups, but more prevalent among infertile men (98.7% vs 88.7%, P = .012), in whom it comprised a greater proportion of the total sperm count (46% vs 24%, P = .022). The majority of sperm present in PEU were seen in PEU1 of both controls (69%) and infertile men (88%). An association was noted between severe oligospermia (sperm counts in PEU (sperm in the urine compared with control, there is a large degree of overlap between the 2 populations, making it difficult to identify a specific threshold to define a positive test. Interpretation of a PEU should be directed by whether the number of sperm in the urine could affect subsequent management.

  3. Uptake and Translocation of Manganese by Native Tree Species in a Constructed Wetland Treating Landfill Leachates

    OpenAIRE

    A. Snow; Abdel E. Ghaly

    2007-01-01

    A surface flow constructed wetland was used to treat stormwater runoff from surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The uptake of manganese by red maple, white birch and red spruce trees growing under flooded soil conditions in the constructed wetland was compared to that of the same trees growing under well drained soil conditions in a nearby reference site. The seasonal variability of manganese and its distribution in different...

  4. Adsorption Study of Electric Arc Furnace Slag for the Removal of Manganese from Solution

    OpenAIRE

    C. L. Beh; Luqman Chuah; Thomas S.Y. Choong; Mohd. Z.B. Kamarudzaman; Khalina Abdan

    2010-01-01

    Problem statement: Steel making slag from Electric Arc Furnace (EAF) is an abundant by-product in Malaysia steel making industry. It has potential to be used for heavy metal removal from contaminated water or waste water. Approach: The aim of this study was to investigate the characteristic and behavior of manganese removal by using EAF slag for efficient metal removal. The removal characteristics of manganese were investigated in term of sorption kinetics and isotherm. The batch adsorption k...

  5. Sublethal effects of cadmium, manganese, lead, zinc and iron on the ...

    African Journals Online (AJOL)

    The toxicological evaluations of cadmium, iron, manganese, lead and zinc were carried out against albino mice model, Mus musculus. On the basis of 96 hrLC50 value, cadmium (0.47 mM) was found to be the most toxic followed by zinc (2.40 mM), lead (2.42 mM), iron (4.25 mM) and manganese (5.70 mM) was least toxic.

  6. Fundamental study of manganese dioxide for catalytic recombustion of exhaust gas of motor car

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyamada, T

    1974-01-01

    The catalytic activities of five manganese dioxide preparations were tested in a pulse reactor to assess their carbon monoxide-oxidizing capability in relation to the catalytic afterburning of automobile exhaust gases. Catalysts prepared from manganese sulfate showed diminished catalytic activity as a result of sulfate poisoning. Higher oxidation activity was obtained with a catalyst prepared by precipitating the permanganate salt in acidic solution. Two forms of carbon monoxide adsorption were demonstrated, each with a characteristic activation energy and reaction temperature.

  7. IMPACTS OF ROAD DE-ICING SALTS ON MANGANESE TRANSPORT TO GROUNDWATER IN ROADSIDE SOILS

    OpenAIRE

    Wen, Yingrong

    2012-01-01

    Manganese (Mn) is an important element in soil, it occur natural in minerals and precipitated as Mn-oxides. Several factors could decide the solubility and mobility of Mn in soil water. In this study, the impact of road de-icing salts (NaCl) on manganese mobilization and transport to groundwater in roadside soils has been investigated by leaching tests. Generally, in the salt solution leachates, the water-soluble concentrations of Mn tended to increase with elevated salt concentrations, sugge...

  8. Synthesis of single crystal manganese oxide octahedral molecular sieve (OMS) nanostructures with tunable tunnels and shapes.

    Science.gov (United States)

    Li, Wei-Na; Yuan, Jikang; Gomez-Mower, Sinue; Sithambaram, Shantakumar; Suib, Steven L

    2006-02-23

    A new and facile route is reported to manipulate the self-assembly synthesis of hierarchically ordered Rb-OMS-2 and pyrolusite with an interesting flowerlike morphology by a direct and mild reaction between rubidium chromateand manganese sulfate without any organic templates. The crystal forms, morphologies, and tunnel sizes of the obtained OMS materials can be controlled. A mechanism for the growth of manganese dioxides with flowerlike architectures was proposed. The obtained products exhibit potential for use in catalysis and other applications.

  9. Wustite-based photoelectrodes with lithium, hydrogen, sodium, magnesium, manganese, zinc and nickel additives

    Science.gov (United States)

    Carter, Emily Ann; Toroker, Maytal Caspary

    2017-08-15

    A photoelectrode, photovoltaic device and photoelectrochemical cell and methods of making are disclosed. The photoelectrode includes an electrode at least partially formed of FeO combined with at least one of lithium, hydrogen, sodium, magnesium, manganese, zinc, and nickel. The electrode may be doped with at least one of lithium, hydrogen, and sodium. The electrode may be alloyed with at least one of magnesium, manganese, zinc, and nickel.

  10. Iron Intermetallic Phases in the Alloy Based on Al-Si-Mg by Applying Manganese

    Directory of Open Access Journals (Sweden)

    Podprocká R.

    2017-09-01

    Full Text Available Manganese is an effective element used for the modification of needle intermetallic phases in Al-Si alloy. These particles seriously degrade mechanical characteristics of the alloy and promote the formation of porosity. By adding manganese the particles are being excluded in more compact shape of “Chinese script” or skeletal form, which are less initiative to cracks as Al5FeSi phase. In the present article, AlSi7Mg0.3 aluminium foundry alloy with several manganese content were studied. The alloy was controlled pollution for achieve higher iron content (about 0.7 wt. % Fe. The manganese were added in amount of 0.2 wt. %, 0.6 wt. %, 1.0 wt. % and 1.4 wt. %. The influence of the alloying element on the process of crystallization of intermetallic phases were compared to microstructural observations. The results indicate that increasing manganese content (> 0.2 wt. % Mn lead to increase the temperature of solidification iron rich phase (TAl5FeSi and reduction this particles. The temperature of nucleation Al-Si eutectic increase with higher manganese content also. At adding 1.4 wt. % Mn grain refinement and skeleton particles were observed.

  11. Kinetics of manganese in MAG/MIG welding with a 18/8/6 wire

    International Nuclear Information System (INIS)

    Tusek, J.

    2001-01-01

    The paper deals with a study of MAG/MIG welding of low-alloy ferritic steel and high-alloy austenitic steel with a 18/8/6 wire. Manganese burn-off from the wire in welding a single-V butt weld was studied. It was found that manganese burns off in the arc during melting of a droplet at the wire end, and from the weld pool during weld formation. The range of manganese burn-of-depends mainly on the type of shielding gas used and the arc length,i. e., from the arc voltage. The manganese burn-off increases with an increase of the content of active gases, i.e., CO 2 and O 2 in the neutral gas i. e., argon. It also increases with an increase in arc voltage. The longer the welding arc, the longer exposition of the filler materials to the welding arc and the wider the penetration, Which allows manganese vapours to evaporate from the weld pool. The most important finding is that manganese burn-off from the 18/8/6 wire during welding of austenitic stainless steel with low-alloy ferritic steel is considerably strong, i.e., from 20% to 30%; nevertheless the wire concerned is perfectly suitable for welding of different types of steel. (Author) 23 refs

  12. Structural and surface changes of cobalt modified manganese oxide during activation and ethanol steam reforming reaction

    Science.gov (United States)

    Gac, Wojciech; Greluk, Magdalena; Słowik, Grzegorz; Turczyniak-Surdacka, Sylwia

    2018-05-01

    Surface and structural changes of unmodified manganese and cobalt-manganese oxide during activation and ethanol steam reforming reaction conditions (ESR) were studied by means of X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction/oxidation (TPR/TPO) and transmission electron microscopy. It was shown that synthesis of cobalt manganese oxide by the redox precipitation method led to the formation of strongly dispersed cobalt ionic species within cryptomelane-based manganese oxide structure. Development of large cube-like MnO nanoparticles with spherical cobalt metallic crystallites decorated by manganese oxide on the high oxidation state and potassium species was observed during reduction. Cobalt manganese catalyst showed high initial activity and selectivity to H2 and CO2 in ethanol stem reforming reaction in the range of 390-480 °C. The drop of ethanol conversion and changes of selectivity with the time-on-stream were observed. An increase of reaction temperature led to intensification of deactivation phenomena. TEM studies evidenced coexistence of Co and CoOx nanoparticles formed under ethanol steam reforming conditions, partially covered by filamentous and encapsulating carbonaceous deposits.

  13. Effect of Manganese Content on the Fabrication of Porous Anodic Alumina

    Directory of Open Access Journals (Sweden)

    C. H. Voon

    2012-01-01

    Full Text Available The influence of manganese content on the formation of well-ordered porous anodic alumina was studied. Porous anodic alumina has been produced on aluminium substrate of different manganese content by single-step anodizing at 50 V in 0.3 M oxalic acid at 15°C for 60 minutes. The well-ordered pore and cell structure was revealed by subjecting the porous anodic alumina to oxide dissolution treatment in a mixture of chromic acid and phosphoric acid. It was found that the manganese content above 1 wt% impaired the regularity of the cell and pore structure significantly, which can be attributed to the presence of secondary phases in the starting material with manganese content above 1 wt%. The pore diameter and interpore distance decreased with the addition of manganese into the substrates. The time variation of current density and the thickness of porous anodic alumina also decreased as a function of the manganese content in the substrates.

  14. In vitro sensitivity testing of Cladobotryum mycophilum to carbendazim and prochloraz manganese

    Directory of Open Access Journals (Sweden)

    Alinesi Chakwiya

    2015-11-01

    Full Text Available Limited information of fungicide efficacy on cultivated mushrooms and resistance development potential is available. Minor crop industries in general have a smaller arsenal of protectants to rely on and the likelihood of resistance build-up is of greater concern. This study focused on Cladobotryum mycophilum's sensitivity to carbendazim and prochloraz manganese following recent reports on decreased efficacy of both fungicides. The median effective dose (ED50 values for carbendazim ranged between 0.02 mg/L and 4.31 mg/L with 60% of the South African isolates being moderately resistant. The highest resistance factor for carbendazim was 215. Prochloraz manganese ED50 values varied from 0.00001 mg/L to 0.55 mg/L. A significant difference in mean ED50 values for both fungicides tested was observed. Using cluster analysis, no discrimination of isolates previously exposed and unexposed to prochloraz manganese was observed. A wide range of differences in ED50 values indicated moderate resistance to carbendazim and high sensitivity to prochloraz manganese among isolates under investigation. Discriminant analysis indicated significant differences between clusters contributed by one or a few variables. This study provided evidence that prochloraz manganese remains highly fungitoxic to C. mycophilum. However, prochloraz manganese is to be used in a disease management strategy in combination with strict farm hygiene management strategies to retain product efficacy and ensure crop protection.

  15. Preparation and capacitive properties of lithium manganese oxide intercalation compound

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Fang; Xie, Yibing, E-mail: ybxie@seu.edu.cn [Southeast University, School of Chemistry and Chemical Engineering (China)

    2015-12-15

    Lithium manganese oxide intercalation compound (Li{sub 0.7}MnO{sub 2}) supported on titanium nitride nanotube array (TiN NTA) was applied as cathode electrode material for lithium-ion supercapacitor application. Li{sub 0.7}MnO{sub 2}/TiN NTA was fabricated through electrochemical deposition and simultaneous intercalation process using TiN NTA as a substrate, Mn(CH{sub 3}COO){sub 2} as manganese source, and Li{sub 2}SO{sub 4} as lithium source. The morphology and microstructure of the Li{sub 0.7}MnO{sub 2}/TiN NTA were characterized by scanning electron microscopy and X-ray diffraction analysis. The electrochemical performance of the Li{sub 0.7}MnO{sub 2}/TiN NTA was investigated by electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge/discharge measurements. Li{sub 0.7}MnO{sub 2}/TiN NTA exhibited higher capacitive performance in Li{sub 2}SO{sub 4} electrolyte solution rather than that in Na{sub 2}SO{sub 4} electrolyte solution, which was due to the different intercalation effects of lithium-ion and sodium-ion. The specific capacitance was improved from 503.3 F g{sup −1} for MnO{sub 2}/TiN NTA to 595.0 F g{sup −1} for Li{sub 0.7}MnO{sub 2}/TiN NTA at a current density of 2 A g{sup −1} in 1.0 M Li{sub 2}SO{sub 4} electrolyte solution, which was due to the intercalation of lithium-ion for Li{sub 0.7}MnO{sub 2}. Li{sub 0.7}MnO{sub 2}/TiN NTA also kept 90.4 % capacity retention after 1000 cycles, presenting a good cycling stability. An all-solid-state lithium-ion supercapacitor was fabricated and showed an energy density of 82.5 Wh kg{sup −1} and a power density of 10.0 kW kg{sup −1}.

  16. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    International Nuclear Information System (INIS)

    Hernroth, Bodil; Baden, Susanne P.; Holm, Kristina; Andre, Tove; Soederhaell, Irene

    2004-01-01

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn 2+ . Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn 2+ ] of 20 mg l -1 for 10 days 24.1 μg ml -1 was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential harm that also

  17. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    Energy Technology Data Exchange (ETDEWEB)

    Hernroth, Bodil [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden)]. E-mail: bodil.hernroth@kmf.gu.se; Baden, Susanne P. [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Holm, Kristina [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Andre, Tove [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden); Soederhaell, Irene [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)

    2004-12-10

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn{sup 2+}. Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn{sup 2+}] of 20 mg l{sup -1} for 10 days 24.1 {mu}g ml{sup -1} was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential

  18. Black manganese-rich crusts on a Gothic cathedral

    Science.gov (United States)

    Macholdt, Dorothea S.; Herrmann, Siegfried; Jochum, Klaus Peter; Kilcoyne, A. L. David; Laubscher, Thomas; Pfisterer, Jonas H. K.; Pöhlker, Christopher; Schwager, Beate; Weber, Bettina; Weigand, Markus; Domke, Katrin F.; Andreae, Meinrat O.

    2017-12-01

    Black manganese-rich crusts are found worldwide on the façades of historical buildings. In this study, they were studied exemplarily on the façade of the Freiburger Münster (Freiburg Minster), Germany, and measured in-situ by portable X-ray fluorescence (XRF). The XRF was calibrated to allow the conversion from apparent mass fractions to Mn surface density (Mn mass per area), to compensate for the fact that portable XRF mass fraction measurements from thin layers violate the assumption of a homogeneous measurement volume. Additionally, 200-nm femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fs LA-ICP-MS) measurements, scanning transmission X-ray microscopy-near edge X-ray absorption fine structure spectroscopy (STXM-NEXAFS), Raman spectroscopy, and imaging by light microscopy were conducted to obtain further insight into the crust material, such as potential biogenic contributions, element distributions, trace element compositions, and organic functional groups. While black crusts of various types are present at many places on the minster's facade, crusts rich in Mn (with a Mn surface density >150 μg cm-2) are restricted to a maximum height of about 7 m. The only exceptions are those developed on the Renaissance-Vorhalle (Renaissance Portico) at a height of about 8 m. This part of the façade had been cleaned and treated with a silicon resin as recently as 2003. These crusts thus accumulated over a period of only 12 years. Yet, they are exceptionally Mn-rich with a surface density of 1200 μg cm-2, and therefore require an accumulation rate of about 100 μg cm-2 Mn per year. Trace element analyses support the theory that vehicle emissions are responsible for most of the Mn supply. Lead, barium, and zinc correlate with manganese, indicating that tire material, brake pads, and resuspended road dust are likely to be the element sources. Microscopic investigations show no organisms on or in the Mn-rich crusts. In contrast, Mn-free black

  19. Nanoscale Structural/Chemical Characterization of Manganese Oxide Surface Layers and Nanoparticles, and the Associated Implications for Drinking Water

    Science.gov (United States)

    Michel Eduardo Vargas Vallejo

    Water treatment facilities commonly reduce soluble contaminants, such as soluble manganese (Mn2+), in water by oxidation and subsequent filtration. Previous studies have shown that conventional porous filter system removes Mn2+ from drinking water by developing Mn-oxides (MnO x(s)) bearing coating layers on the surface of filter media. Multiple models have been developed to explain this Mn2+ removal process and the formation mechanism of MnOx(s) coatings. Both, experimental and theoretical studies to date have been largely focused on the micrometer to millimeter scale range; whereas, coating layers are composed of nanoscale particles and films. Hence, understanding the nanoscale particle and film formation mechanisms is essential to comprehend the complexity of soluble contaminant removal processes. The primary objective of this study was to understand the initial MnOx(s) coating formation mechanisms and evaluate the influence of filter media characteristics on these processes. We pursued this objective by characterizing at the micro and nanoscale MnO x(s) coatings developed on different filter media by bench-scale column tests with simulating inorganic aqueous chemistry of a typical coagulation fresh water treatment plant, where free chlorine is present across filter bed. Analytical SEM and TEM, powder and synchrotron-based XRD, XPS, and ICPMS were used for characterization of coatings, filter media and water solution elemental chemistry. A secondary objective was to model how surface coating formation occurred and its correlation with experimentally observed physical characteristics. This modeling exercise indicates that surface roughness and morphology of filtering media are the major contributing factors in surface coating formation process. Contrary to previous models that assumed a uniform distribution and growth of surface coating, the experimental results showed that greater amounts of coating were developed in rougher areas. At the very early stage of

  20. Defining safety goals. 2. Basic Consideration on Defining Safety Goals

    International Nuclear Information System (INIS)

    Hakata, T.

    2001-01-01

    cancer and severe hereditary effects are 10 x 10 -2 /Sv and 1.3 x10 -2 /Sv, respectively. The basic safety goals can be expressed by the complementary accumulative distribution function (CCDF) of dose versus frequencies of events: Pc(C > Cp) 5 (Cp/Co) -α . The aversion factor a is here expressed by the following arbitrary equation, which gives a polynomial curve of the order of m on a logarithmic plane: α = a+b(log(Cp/Co)) m , where: Pc = CCDF frequency for Cp (/yr), Cp = dose (mSv), Co = Cp for Pc =1, a, b, m = constants. Figure 1 shows a typical tolerable risk profile (risk limit curve), which is drawn so that all the points obtained in the previous discussions are above the curve (Co=1, a=1, b=0.0772, and m = 2). Safety criteria by ANS (Ref. 2) and SHE (Ref. 3) are shown in Fig. 1 for comparison. An aversion of a factor of 2 is resulted between 1 mSv and 1 Sv. No ALARA is included, which must be considered in defining specific safety goals. The frequency of a single class of events must be lower than the CCDF profile, and a curve lower by a factor of 10 is drawn in Fig. 1. The doses referenced in the current Japanese safety guidelines and site criteria are shown in Fig. 1. The referenced doses seem reasonable, considering the conservatism in the analysis of design-basis accidents. Specific safety goals for each sort of facility can be defined based on the basic safety goals, reflecting the characteristics of the facilities and considering ALARA. The indexes of engineering terms, such as CMF and LERF, are preferable for nuclear power plants, although interpretation from dose to the engineering terms is needed. Other indexes may be used (such as frequency of criticality accidents, etc.) for facilities except for power plants. The applicability of safety goals will thus be improved. Figure 2 shows the relative risk factors (1, 1%, and 0.1%) versus the severity of radiation effects. This might indicate the adequacy of the risk factors. The absolute risk limits, which